Sample records for 3d datasets comparison

  1. Comparison of global 3-D aviation emissions datasets

    S. C. Olsen


    Full Text Available Aviation emissions are unique from other transportation emissions, e.g., from road transportation and shipping, in that they occur at higher altitudes as well as at the surface. Aviation emissions of carbon dioxide, soot, and water vapor have direct radiative impacts on the Earth's climate system while emissions of nitrogen oxides (NOx, sulfur oxides, carbon monoxide (CO, and hydrocarbons (HC impact air quality and climate through their effects on ozone, methane, and clouds. The most accurate estimates of the impact of aviation on air quality and climate utilize three-dimensional chemistry-climate models and gridded four dimensional (space and time aviation emissions datasets. We compare five available aviation emissions datasets currently and historically used to evaluate the impact of aviation on climate and air quality: NASA-Boeing 1992, NASA-Boeing 1999, QUANTIFY 2000, Aero2k 2002, and AEDT 2006 and aviation fuel usage estimates from the International Energy Agency. Roughly 90% of all aviation emissions are in the Northern Hemisphere and nearly 60% of all fuelburn and NOx emissions occur at cruise altitudes in the Northern Hemisphere. While these datasets were created by independent methods and are thus not strictly suitable for analyzing trends they suggest that commercial aviation fuelburn and NOx emissions increased over the last two decades while HC emissions likely decreased and CO emissions did not change significantly. The bottom-up estimates compared here are consistently lower than International Energy Agency fuelburn statistics although the gap is significantly lower in the more recent datasets. Overall the emissions distributions are quite similar for fuelburn and NOx while for CO and HC there are relatively larger differences. There are however some distinct differences in the altitude distribution of emissions in certain regions for the Aero2k dataset.

  2. Comparison of global 3-D aviation emissions datasets

    S. C. Olsen


    Full Text Available Aviation emissions are unique from other transportation emissions, e.g., from road transportation and shipping, in that they occur at higher altitudes as well as at the surface. Aviation emissions of carbon dioxide, soot, and water vapor have direct radiative impacts on the Earth's climate system while emissions of nitrogen oxides (NOx, sulfur oxides, carbon monoxide (CO, and hydrocarbons (HC impact air quality and climate through their effects on ozone, methane, and clouds. The most accurate estimates of the impact of aviation on air quality and climate utilize three-dimensional chemistry-climate models and gridded four dimensional (space and time aviation emissions datasets. We compare five available aviation emissions datasets currently and historically used to evaluate the impact of aviation on climate and air quality: NASA-Boeing 1992, NASA-Boeing 1999, QUANTIFY 2000, Aero2k 2002, and AEDT 2006 and aviation fuel usage estimates from the International Energy Agency. Roughly 90% of all aviation emissions are in the Northern Hemisphere and nearly 60% of all fuelburn and NOx emissions occur at cruise altitudes in the Northern Hemisphere. While these datasets were created by independent methods and are thus not strictly suitable for analyzing trends they suggest that commercial aviation fuelburn and NOx emissions increased over the last two decades while HC emissions likely decreased and CO emissions did not change significantly. The bottom-up estimates compared here are consistently lower than International Energy Agency fuelburn statistics although the gap is significantly smaller in the more recent datasets. Overall the emissions distributions are quite similar for fuelburn and NOx with regional peaks over the populated land masses of North America, Europe, and East Asia. For CO and HC there are relatively larger differences. There are however some distinct differences in the altitude distribution

  3. 3DSEM: A 3D microscopy dataset

    Ahmad P. Tafti


    Full Text Available The Scanning Electron Microscope (SEM as a 2D imaging instrument has been widely used in many scientific disciplines including biological, mechanical, and materials sciences to determine the surface attributes of microscopic objects. However the SEM micrographs still remain 2D images. To effectively measure and visualize the surface properties, we need to truly restore the 3D shape model from 2D SEM images. Having 3D surfaces would provide anatomic shape of micro-samples which allows for quantitative measurements and informative visualization of the specimens being investigated. The 3DSEM is a dataset for 3D microscopy vision which is freely available at [1] for any academic, educational, and research purposes. The dataset includes both 2D images and 3D reconstructed surfaces of several real microscopic samples.

  4. A Large-Scale 3D Object Recognition dataset

    Sølund, Thomas; Glent Buch, Anders; Krüger, Norbert;


    This paper presents a new large scale dataset targeting evaluation of local shape descriptors and 3d object recognition algorithms. The dataset consists of point clouds and triangulated meshes from 292 physical scenes taken from 11 different views; a total of approximately 3204 views. Each...

  5. The interactive presentation of 3D information obtained from reconstructed datasets and 3D placement of single histological sections with the 3D portable document format

    B.A. de Boer; A.T. Soufan; J. Hagoort; T.J. Mohun; M.J.B. van den Hoff; A. Hasman; F.P.J.M. Voorbraak; A.F.M. Moorman; J.M. Ruijter


    Interpretation of the results of anatomical and embryological studies relies heavily on proper visualization of complex morphogenetic processes and patterns of gene expression in a three-dimensional (3D) context. However, reconstruction of complete 3D datasets is time consuming and often researchers

  6. Interacting with Large 3D Datasets on a Mobile Device.

    Schultz, Chris; Bailey, Mike


    A detail-on-demand scheme can alleviate both memory and GPU pressure on mobile devices caused by volume rendering. This approach allows a user to explore an entire dataset at its native resolution while simultaneously constraining the texture size being rendered to a dimension that does not exceed the processing capabilities of a portable device. This scheme produces higher-quality, more focused images rendered at interactive frame rates, while preserving the native resolution of the dataset.

  7. Efficient segmentation of 3D fluoroscopic datasets from mobile C-arm

    Styner, Martin A.; Talib, Haydar; Singh, Digvijay; Nolte, Lutz-Peter


    The emerging mobile fluoroscopic 3D technology linked with a navigation system combines the advantages of CT-based and C-arm-based navigation. The intra-operative, automatic segmentation of 3D fluoroscopy datasets enables the combined visualization of surgical instruments and anatomical structures for enhanced planning, surgical eye-navigation and landmark digitization. We performed a thorough evaluation of several segmentation algorithms using a large set of data from different anatomical regions and man-made phantom objects. The analyzed segmentation methods include automatic thresholding, morphological operations, an adapted region growing method and an implicit 3D geodesic snake method. In regard to computational efficiency, all methods performed within acceptable limits on a standard Desktop PC (30sec-5min). In general, the best results were obtained with datasets from long bones, followed by extremities. The segmentations of spine, pelvis and shoulder datasets were generally of poorer quality. As expected, the threshold-based methods produced the worst results. The combined thresholding and morphological operations methods were considered appropriate for a smaller set of clean images. The region growing method performed generally much better in regard to computational efficiency and segmentation correctness, especially for datasets of joints, and lumbar and cervical spine regions. The less efficient implicit snake method was able to additionally remove wrongly segmented skin tissue regions. This study presents a step towards efficient intra-operative segmentation of 3D fluoroscopy datasets, but there is room for improvement. Next, we plan to study model-based approaches for datasets from the knee and hip joint region, which would be thenceforth applied to all anatomical regions in our continuing development of an ideal segmentation procedure for 3D fluoroscopic images.

  8. 3D Printing of CT Dataset: Validation of an Open Source and Consumer-Available Workflow.

    Bortolotto, Chandra; Eshja, Esmeralda; Peroni, Caterina; Orlandi, Matteo A; Bizzotto, Nicola; Poggi, Paolo


    The broad availability of cheap three-dimensional (3D) printing equipment has raised the need for a thorough analysis on its effects on clinical accuracy. Our aim is to determine whether the accuracy of 3D printing process is affected by the use of a low-budget workflow based on open source software and consumer's commercially available 3D printers. A group of test objects was scanned with a 64-slice computed tomography (CT) in order to build their 3D copies. CT datasets were elaborated using a software chain based on three free and open source software. Objects were printed out with a commercially available 3D printer. Both the 3D copies and the test objects were measured using a digital professional caliper. Overall, the objects' mean absolute difference between test objects and 3D copies is 0.23 mm and the mean relative difference amounts to 0.55 %. Our results demonstrate that the accuracy of 3D printing process remains high despite the use of a low-budget workflow.

  9. Computational Graph Model for 3D Cells Tracking in Zebra Fish Datasets

    Zhang, Lelin; Xiong, Hongkai; Zhao, Yang; Zhang, Kai; Zhou, Xiaobo


    This paper leads to a novel technique for tracking and identification of zebra-fish cells in 3D image sequences, extending graph-based multi-objects tracking algorithm to 3D applications. As raised in previous work of 2D graph-based method, separated cells are modeled as vertices that connected by edges. Then the tracking work is simplified to that of vertices matching between graphs generated from consecutive frames. Graph-based tracking is composed of three steps: graph generation, initial source vertices selection and graph saturation. To satisfy demands in this work separated cell records are segmented from original datasets using 3D level-set algorithms. Besides, advancements are achieved in each of the step including graph regulations, multi restrictions on source vertices and enhanced flow quantifications. Those strategies make a good compensation for graph-based multi-objects tracking method in 2D space. Experiments are carried out in 3D datasets sampled from zebra fish, results of which shows that this enhanced method could be potentially applied to tracking of objects with diverse features.

  10. MR neurography with multiplanar reconstruction of 3D MRI datasets: an anatomical study and clinical applications

    Freund, Wolfgang; Aschoff, Andrik J.; Stuber, Gregor; Schmitz, Bernd [University Hospitals Ulm, Clinic for Diagnostic and Interventional Radiology, Ulm (Germany); Brinkmann, Alexander; Wagner, Florian; Dinse, Alexander [University Hospitals Ulm, Department of Anesthesiology, Ulm (Germany)


    Extracranial MR neurography has so far mainly been used with 2D datasets. We investigated the use of 3D datasets for peripheral neurography of the sciatic nerve. A total of 40 thighs (20 healthy volunteers) were examined with a coronally oriented magnetization-prepared rapid acquisition gradient echo sequence with isotropic voxels of 1 x 1 x 1 mm and a field of view of 500 mm. Anatomical landmarks were palpated and marked with MRI markers. After MR scanning, the sciatic nerve was identified by two readers independently in the resulting 3D dataset. In every volunteer, the sciatic nerve could be identified bilaterally over the whole length of the thigh, even in areas of close contact to isointense muscles. The landmark of the greater trochanter was falsely palpated by 2.2 cm, and the knee joint by 1 cm. The mean distance between the bifurcation of the sciatic nerve and the knee-joint gap was 6 cm ({+-}1.8 cm). The mean results of the two readers differed by 1-6%. With the described method of MR neurography, the sciatic nerve was depicted reliably and objectively in great anatomical detail over the whole length of the thigh. Important anatomical information can be obtained. The clinical applications of MR neurography for the brachial plexus and lumbosacral plexus/sciatic nerve are discussed. (orig.)

  11. Compilation of 3D soil texture dataset applying indicator kriging method, integrating soil- and agrogeological databases

    Zsófia Bakacsi


    Full Text Available In the frame of the WateRisk Project (2009-2011 hydrological model has been developed for flood risk analysis, demanding the spatial distribution of soil physical properties. 3D, regional scale, spatial datasets were elaborated for pilots, based on the thematic harmonization, horizontal and vertical fitting and interpolation of soil physical parameters originating from two different databases. The profile dataset of the Digital Kreybig Soil Information System is owned by the Research Institute for Soil Science and Agricultural Chemistry; the Shallow Boring Database is managed by the Hungarian Geological Institute. The resultant databases describe the physical properties by texture classes of each of the soil layers (10 cm steps till 1 m depth and geological formations (50 cm steps below 1 m down to the ground water table depth

  12. New results from a 3D seismic academic dataset across the west Galicia margin

    Lymer, Gaël; Cresswell, Derren; Reston, Tim; Stevenson, Carl; Sawyer, Dale


    The west Galicia margin (western Spain) is a magma-poor margin and has limited sedimentary cover, providing ideal conditions to study the processes of continental extension and break-up through seismic imaging. The margin is characterised by hyper-extended continental crust, well defined rotated faults blocks with associated syn-kinematic sedimentary wedges, and exhumed serpentinized continental mantle. Faulted blocks overlie a bright reflection, the S reflector, generally interpreted as both a detachment and the crust-mantle boundary. But open questions remain concerning the role of the S detachment in extension leading to breakup. To study further the S reflection and its role in continental breakup, a new 3D high-resolution multi-channel seismic dataset has been acquired over the Galicia margin during summer 2013. It consists in 800 inlines and 5000 crosslines distributed on a ~680 km2 areal. This 3D dataset is thus the largest academic one of its kind. It extends across the edge of the continental crust and captures the 3D nature of extension and break-up of the northern Atlantic continental margins. Here we present some results from our interpretations of the 3D volume, which allow various horizons, including the base of the post-rift sedimentary cover, the top basement and the S reflector, to be mapped out in 3D. These maps provide 3D views of the margin structure and also reveal the texture of each horizon. We also focus on the internal structure of some of the faulted blocks through interpretation of the crustal normal faults. The main normal faults are generally connected downward on the S reflector, revealing strong interactions between crustal thinning and the S. The half-grabens and the fault blocks are dominantly N-S oriented, but the crustal structures vary both along strike and cross strike. We particularly observe an intriguingly NW-SE trend, highlighted by a pronounced low within the crest of the fault blocks. We also observe this trend from

  13. 3D geometric split-merge segmentation of brain MRI datasets.

    Marras, Ioannis; Nikolaidis, Nikolaos; Pitas, Ioannis


    In this paper, a novel method for MRI volume segmentation based on region adaptive splitting and merging is proposed. The method, called Adaptive Geometric Split Merge (AGSM) segmentation, aims at finding complex geometrical shapes that consist of homogeneous geometrical 3D regions. In each volume splitting step, several splitting strategies are examined and the most appropriate is activated. A way to find the maximal homogeneity axis of the volume is also introduced. Along this axis, the volume splitting technique divides the entire volume in a number of large homogeneous 3D regions, while at the same time, it defines more clearly small homogeneous regions within the volume in such a way that they have greater probabilities of survival at the subsequent merging step. Region merging criteria are proposed to this end. The presented segmentation method has been applied to brain MRI medical datasets to provide segmentation results when each voxel is composed of one tissue type (hard segmentation). The volume splitting procedure does not require training data, while it demonstrates improved segmentation performance in noisy brain MRI datasets, when compared to the state of the art methods.

  14. Automated reconstruction of curvilinear fibres from 3D datasets acquired by X-ray microtomography.

    Eberhardt, C N; Clarke, A R


    The characterization of fibrous structures is important in both composites and textiles research for relating to the bulk properties of the material. However, the microscopic nature of the fibres and their high densities make them very difficult to characterize. Many techniques have been developed for the measurement and characterization of fibrous structures but they tend to be restricted to measurements on the sample surface or within physical cross-sections. X-ray microtomography can be used to non-destructively probe the internal structure of a range of fibrous materials, providing large amounts of 3D data. A technique has been developed for tracing fibres within 3D datasets acquired by X-ray microtomography and this has been applied to a glass fibre reinforced composite and also a non-woven textile sample. The 3D fibrous structures of both samples were successfully reconstructed and their fibre orientation distributions calculated. This technique enables novel characterizations, such as the through-thickness variation of fibre orientation in non-wovens.

  15. Improved 3D density modelling of the Central Andes from combining terrestrial datasets with satellite based datasets

    Schaller, Theresa; Sobiesiak, Monika; Götze, Hans-Jürgen; Ebbing, Jörg


    As horizontal gravity gradients are proxies for large stresses, the uniquely high gravity gradients of the South American continental margin seem to be indicative for the frequently occurring large earthquakes at this plate boundary. It has been observed that these earthquakes can break repeatedly the same respective segment but can also combine to form M>9 earthquakes at the end of longer seismic cycles. A large seismic gap left behind by the 1877 M~9 earthquake existed in the northernmost part of Chile. This gap has partially been ruptured in the Mw 7.7 2007 Tocopilla earthquake and the Mw 8.2 2014 Pisagua earthquake. The nature of this seismological segmentation and the distribution of energy release in an earthquake is part of ongoing research. It can be assumed that both features are related to thickness variations of high density bodies located in the continental crust of the coastal area. These batholiths produce a clear maximum in the gravity signal. Those maxima also show a good spatial correlation with seismic asperity structures and seismological segment boundaries. Understanding of the tectonic situation can be improved through 3D forward density modelling of the gravity field. Problems arise in areas with less ground measurements. Especially in the high Andes severe gaps exist due to the inaccessibility of some regions. Also the transition zone between on and offshore date data displays significant problems, particularly since this is the area that is most interesting in terms of seismic hazard. We modelled the continental and oceanic crust and upper mantle using different gravity datasets. The first one includes terrestrial data measured at a station spacing of 5 km or less along all passable roads combined with satellite altimetry data offshore. The second data set is the newly released EIGEN-6C4 which combines the latest satellite data with ground measurements. The spherical harmonics maximum degree of EIGEN-6C4 is 2190 which corresponds to a

  16. 3D reconstruction software comparison for short sequences

    Strupczewski, Adam; Czupryński, BłaŻej


    Large scale multiview reconstruction is recently a very popular area of research. There are many open source tools that can be downloaded and run on a personal computer. However, there are few, if any, comparisons between all the available software in terms of accuracy on small datasets that a single user can create. The typical datasets for testing of the software are archeological sites or cities, comprising thousands of images. This paper presents a comparison of currently available open source multiview reconstruction software for small datasets. It also compares the open source solutions with a simple structure from motion pipeline developed by the authors from scratch with the use of OpenCV and Eigen libraries.

  17. 3D P-wave velocity structure of the deep Galicia rifted margin: A first analysis of the Galicia 3D wide-angle seismic dataset

    Bayrakci, Gaye; Minshull, Timothy A.; Davy, Richard G.; Karplus, Marianne S.; Kaeschen, Dirk; Papenberg, Cord; Krabbenhoeft, Anne; Sawyer, Dale; Reston, Timothy J.; Shillington, Donna J.; Ranero, César R.


    Galicia 3D, a reflection-refraction and long offset seismic experiment was carried out from May through September 2013, at the Galicia rifted margin (in the northeast Atlantic Ocean, west of Spain) as a collaboration between US, UK, German and Spanish groups. The 3D multichannel seismic acquisition conducted by R/V Marcus Langseth covered a 64 km by 20 km (1280 km2) zone where the main geological features are the Peridotite Ridge (PR), composed of serpentinized peridotite and thought be upper mantle exhumed to the seafloor during rifting, and the S reflector which has been interpreted to be a low angle detachment fault overlain by fault bounded, rotated, continental crustal blocks. In the 3D box, two airgun arrays of 3300 were fired alternately (in flip-flop configuration) every 37.5 m. All shots are recorded by 44 short period four component ocean bottom seismometers (OBS) and 26 ocean bottom hydrophones (OBH) deployed and recovered by R/V Poseidon, as well as four 6 km hydrophone streamers with 12.5 m channel spacing towed by R/V Marcus Langseth. We present the preliminary results of the first arrival time tomography study which is carried out with a subset of the wide-angle dataset, in order to generate a 3D P-wave velocity volume for the entire depth sampled by the reflection data. After the relocation of OBSs and OBHs, an automatic first-arrival time picking approach is applied to a subset of the dataset, which comprises more than 5.5 million source-receiver pairs. Then, the first-arrival times are checked visually, in 3-dimensions. The a priori model used for the first-arrival time tomography is built up using information from previous seismic surveys carried out at the Galicia margin (e.g. ISE, 1997). The FAST algorithm of Zelt and Barton (1998) is used for the first-arrival time inversion. The 3D P-wave velocity volume can be used in interpreting the reflection dataset, as a starting point for migration, to quantify the thinning of the crustal layers

  18. Comparison of Shallow Survey 2012 Multibeam Datasets

    Ramirez, T. M.


    The purpose of the Shallow Survey common dataset is a comparison of the different technologies utilized for data acquisition in the shallow survey marine environment. The common dataset consists of a series of surveys conducted over a common area of seabed using a variety of systems. It provides equipment manufacturers the opportunity to showcase their latest systems while giving hydrographic researchers and scientists a chance to test their latest algorithms on the dataset so that rigorous comparisons can be made. Five companies collected data for the Common Dataset in the Wellington Harbor area in New Zealand between May 2010 and May 2011; including Kongsberg, Reson, R2Sonic, GeoAcoustics, and Applied Acoustics. The Wellington harbor and surrounding coastal area was selected since it has a number of well-defined features, including the HMNZS South Seas and HMNZS Wellington wrecks, an armored seawall constructed of Tetrapods and Akmons, aquifers, wharves and marinas. The seabed inside the harbor basin is largely fine-grained sediment, with gravel and reefs around the coast. The area outside the harbor on the southern coast is an active environment, with moving sand and exposed reefs. A marine reserve is also in this area. For consistency between datasets, the coastal research vessel R/V Ikatere and crew were used for all surveys conducted for the common dataset. Using Triton's Perspective processing software multibeam datasets collected for the Shallow Survey were processed for detail analysis. Datasets from each sonar manufacturer were processed using the CUBE algorithm developed by the Center for Coastal and Ocean Mapping/Joint Hydrographic Center (CCOM/JHC). Each dataset was gridded at 0.5 and 1.0 meter resolutions for cross comparison and compliance with International Hydrographic Organization (IHO) requirements. Detailed comparisons were made of equipment specifications (transmit frequency, number of beams, beam width), data density, total uncertainty, and

  19. X3D-Earth: Full Globe Coverage Utilizing Multiple Dataset


    49 a. JeoSpace ..................................................................................49 b. DNC to X3D...ARC Digitized Radar Graphics (CADRG) ........58 b. Digital Nautical Charts ( DNC )...............................................58 3. Bathymetry...59 a. Digital Nautical Charts ( DNC

  20. Prognostic breast cancer signature identified from 3D culture model accurately predicts clinical outcome across independent datasets

    Martin, Katherine J.; Patrick, Denis R.; Bissell, Mina J.; Fournier, Marcia V.


    One of the major tenets in breast cancer research is that early detection is vital for patient survival by increasing treatment options. To that end, we have previously used a novel unsupervised approach to identify a set of genes whose expression predicts prognosis of breast cancer patients. The predictive genes were selected in a well-defined three dimensional (3D) cell culture model of non-malignant human mammary epithelial cell morphogenesis as down-regulated during breast epithelial cell acinar formation and cell cycle arrest. Here we examine the ability of this gene signature (3D-signature) to predict prognosis in three independent breast cancer microarray datasets having 295, 286, and 118 samples, respectively. Our results show that the 3D-signature accurately predicts prognosis in three unrelated patient datasets. At 10 years, the probability of positive outcome was 52, 51, and 47 percent in the group with a poor-prognosis signature and 91, 75, and 71 percent in the group with a good-prognosis signature for the three datasets, respectively (Kaplan-Meier survival analysis, p<0.05). Hazard ratios for poor outcome were 5.5 (95% CI 3.0 to 12.2, p<0.0001), 2.4 (95% CI 1.6 to 3.6, p<0.0001) and 1.9 (95% CI 1.1 to 3.2, p = 0.016) and remained significant for the two larger datasets when corrected for estrogen receptor (ER) status. Hence the 3D-signature accurately predicts breast cancer outcome in both ER-positive and ER-negative tumors, though individual genes differed in their prognostic ability in the two subtypes. Genes that were prognostic in ER+ patients are AURKA, CEP55, RRM2, EPHA2, FGFBP1, and VRK1, while genes prognostic in ER patients include ACTB, FOXM1 and SERPINE2 (Kaplan-Meier p<0.05). Multivariable Cox regression analysis in the largest dataset showed that the 3D-signature was a strong independent factor in predicting breast cancer outcome. The 3D-signature accurately predicts breast cancer outcome across multiple datasets and holds prognostic

  1. 3D Modeling of Iran and Surrounding Areas from Simultaneous Inversion of Multiple Geophysical Datasets


    Nevertheless, it is well known that traditional state-of-the-art inversion techniques suffer from poor resolution and nonuniqueness , especially when a...and to provide adequate starting models for 3D waveform inversion approaches. ACKNOWLEDGEMENTS We thank the scientists, engineers , and technicians

  2. HS3D, A Dataset of Homo Sapiens Splice Regions, and its Extraction Procedure from a Major Public Database

    Pollastro, Pasquale; Rampone, Salvatore

    The aim of this work is to describe a cleaning procedure of GenBank data, producing material to train and to assess the prediction accuracy of computational approaches for gene characterization. A procedure (GenBank2HS3D) has been defined, producing a dataset (HS3D - Homo Sapiens Splice Sites Dataset) of Homo Sapiens Splice regions extracted from GenBank (Rel.123 at this time). It selects, from the complete GenBank Primate Division, entries of Human Nuclear DNA according with several assessed criteria; then it extracts exons and introns from these entries (actually 4523 + 3802). Donor and acceptor sites are then extracted as windows of 140 nucleotides around each splice site (3799 + 3799). After discarding windows not including canonical GT-AG junctions (65 + 74), including insufficient data (not enough material for a 140 nucleotide window) (686 + 589), including not AGCT bases (29 + 30), and redundant (218 + 226), the remaining windows (2796 + 2880) are reported in the dataset. Finally, windows of false splice sites are selected by searching canonical GT-AG pairs in not splicing positions (271 937 + 332 296). The false sites in a range +/- 60 from a true splice site are marked as proximal. HS3D, release 1.2 at this time, is available at the Web server of the University of Sannio:

  3. Visualizing and Tracking Evolving Features in 3D Unstructured and Adaptive Datasets

    Silver, D.; Zabusky, N.


    The massive amounts of time-varying datasets being generated demand new visualization and quantification techniques. Visualization alone is not sufficient. Without proper measurement information/computations real science cannot be done. Our focus is this work was to combine visualization with quantification of the data to allow for advanced querying and searching. As part of this proposal, we have developed a feature extraction adn tracking methodology which allows researcher to identify features of interest and follow their evolution over time. The implementation is distributed and operates over data In-situ: where it is stored and when it was computed.

  4. A large dataset of synthetic SEM images of powder materials and their ground truth 3D structures.

    DeCost, Brian L; Holm, Elizabeth A


    This data article presents a data set comprised of 2048 synthetic scanning electron microscope (SEM) images of powder materials and descriptions of the corresponding 3D structures that they represent. These images were created using open source rendering software, and the generating scripts are included with the data set. Eight particle size distributions are represented with 256 independent images from each. The particle size distributions are relatively similar to each other, so that the dataset offers a useful benchmark to assess the fidelity of image analysis techniques. The characteristics of the PSDs and the resulting images are described and analyzed in more detail in the research article "Characterizing powder materials using keypoint-based computer vision methods" (B.L. DeCost, E.A. Holm, 2016) [1]. These data are freely available in a Mendeley Data archive "A large dataset of synthetic SEM images of powder materials and their ground truth 3D structures" (B.L. DeCost, E.A. Holm, 2016) located at[2] for any academic, educational, or research purposes.

  5. A large dataset of synthetic SEM images of powder materials and their ground truth 3D structures

    Brian L. DeCost


    Full Text Available This data article presents a data set comprised of 2048 synthetic scanning electron microscope (SEM images of powder materials and descriptions of the corresponding 3D structures that they represent. These images were created using open source rendering software, and the generating scripts are included with the data set. Eight particle size distributions are represented with 256 independent images from each. The particle size distributions are relatively similar to each other, so that the dataset offers a useful benchmark to assess the fidelity of image analysis techniques. The characteristics of the PSDs and the resulting images are described and analyzed in more detail in the research article “Characterizing powder materials using keypoint-based computer vision methods” (B.L. DeCost, E.A. Holm, 2016 [1]. These data are freely available in a Mendeley Data archive “A large dataset of synthetic SEM images of powder materials and their ground truth 3D structures” (B.L. DeCost, E.A. Holm, 2016 located at [2] for any academic, educational, or research purposes.

  6. Fast multi-core based multimodal registration of 2D cross-sections and 3D datasets

    Pielot Rainer


    Full Text Available Abstract Background Solving bioinformatics tasks often requires extensive computational power. Recent trends in processor architecture combine multiple cores into a single chip to improve overall performance. The Cell Broadband Engine (CBE, a heterogeneous multi-core processor, provides power-efficient and cost-effective high-performance computing. One application area is image analysis and visualisation, in particular registration of 2D cross-sections into 3D image datasets. Such techniques can be used to put different image modalities into spatial correspondence, for example, 2D images of histological cuts into morphological 3D frameworks. Results We evaluate the CBE-driven PlayStation 3 as a high performance, cost-effective computing platform by adapting a multimodal alignment procedure to several characteristic hardware properties. The optimisations are based on partitioning, vectorisation, branch reducing and loop unrolling techniques with special attention to 32-bit multiplies and limited local storage on the computing units. We show how a typical image analysis and visualisation problem, the multimodal registration of 2D cross-sections and 3D datasets, benefits from the multi-core based implementation of the alignment algorithm. We discuss several CBE-based optimisation methods and compare our results to standard solutions. More information and the source code are available from Conclusions The results demonstrate that the CBE processor in a PlayStation 3 accelerates computational intensive multimodal registration, which is of great importance in biological/medical image processing. The PlayStation 3 as a low cost CBE-based platform offers an efficient option to conventional hardware to solve computational problems in image processing and bioinformatics.

  7. BlastNeuron for Automated Comparison, Retrieval and Clustering of 3D Neuron Morphologies.

    Wan, Yinan; Long, Fuhui; Qu, Lei; Xiao, Hang; Hawrylycz, Michael; Myers, Eugene W; Peng, Hanchuan


    Characterizing the identity and types of neurons in the brain, as well as their associated function, requires a means of quantifying and comparing 3D neuron morphology. Presently, neuron comparison methods are based on statistics from neuronal morphology such as size and number of branches, which are not fully suitable for detecting local similarities and differences in the detailed structure. We developed BlastNeuron to compare neurons in terms of their global appearance, detailed arborization patterns, and topological similarity. BlastNeuron first compares and clusters 3D neuron reconstructions based on global morphology features and moment invariants, independent of their orientations, sizes, level of reconstruction and other variations. Subsequently, BlastNeuron performs local alignment between any pair of retrieved neurons via a tree-topology driven dynamic programming method. A 3D correspondence map can thus be generated at the resolution of single reconstruction nodes. We applied BlastNeuron to three datasets: (1) 10,000+ neuron reconstructions from a public morphology database, (2) 681 newly and manually reconstructed neurons, and (3) neurons reconstructions produced using several independent reconstruction methods. Our approach was able to accurately and efficiently retrieve morphologically and functionally similar neuron structures from large morphology database, identify the local common structures, and find clusters of neurons that share similarities in both morphology and molecular profiles.

  8. 3D granulometry: grain-scale shape and size distribution from point cloud dataset of river environments

    Steer, Philippe; Lague, Dimitri; Gourdon, Aurélie; Croissant, Thomas; Crave, Alain


    The grain-scale morphology of river sediments and their size distribution are important factors controlling the efficiency of fluvial erosion and transport. In turn, constraining the spatial evolution of these two metrics offer deep insights on the dynamics of river erosion and sediment transport from hillslopes to the sea. However, the size distribution of river sediments is generally assessed using statistically-biased field measurements and determining the grain-scale shape of river sediments remains a real challenge in geomorphology. Here we determine, with new methodological approaches based on the segmentation and geomorphological fitting of 3D point cloud dataset, the size distribution and grain-scale shape of sediments located in river environments. Point cloud segmentation is performed using either machine-learning algorithms or geometrical criterion, such as local plan fitting or curvature analysis. Once the grains are individualized into several sub-clouds, each grain-scale morphology is determined using a 3D geometrical fitting algorithm applied on the sub-cloud. If different geometrical models can be conceived and tested, only ellipsoidal models were used in this study. A phase of results checking is then performed to remove grains showing a best-fitting model with a low level of confidence. The main benefits of this automatic method are that it provides 1) an un-biased estimate of grain-size distribution on a large range of scales, from centimeter to tens of meters; 2) access to a very large number of data, only limited by the number of grains in the point-cloud dataset; 3) access to the 3D morphology of grains, in turn allowing to develop new metrics characterizing the size and shape of grains. The main limit of this method is that it is only able to detect grains with a characteristic size greater than the resolution of the point cloud. This new 3D granulometric method is then applied to river terraces both in the Poerua catchment in New-Zealand and

  9. Comparison of the 3D Protein Structure Prediction Algorithms

    Fadhl M. Al-Akwaa,; Husam Elhetari


    Determining protein 3D structure is important to known protein functions. Protein structure could be determined experimentally and computationally. Experimental methods are expensive and time consuming whereas computational methods are the alternative solution. From the other hand, computational methods require strong computing power, assumed models and effective algorithms. In this paper we compare the performance of these algorithms. We find that Genetic Algorithm with impro...

  10. Constraints on 3D fault and fracture distribution in layered volcanic- volcaniclastic sequences from terrestrial LIDAR datasets: Faroe Islands

    Raithatha, Bansri; McCaffrey, Kenneth; Walker, Richard; Brown, Richard; Pickering, Giles


    Hydrocarbon reservoirs commonly contain an array of fine-scale structures that control fluid flow in the subsurface, such as polyphase fracture networks and small-scale fault zones. These structures are unresolvable using seismic imaging and therefore outcrop-based studies have been used as analogues to characterize fault and fracture networks and assess their impact on fluid flow in the subsurface. To maximize recovery and enhance production, it is essential to understand the geometry, physical properties, and distribution of these structures in 3D. Here we present field data and terrestrial LIDAR-derived 3D, photo-realistic virtual outcrops of fault zones at a range of displacement scales (0.001- 4.5 m) within a volcaniclastic sand- and basaltic lava unit sequence in the Faroe Islands. Detailed field observations were used to constrain the virtual outcrop dataset, and a workflow has been developed to build a discrete fracture network (DFN) models in GOCAD® from these datasets. Model construction involves three main stages: (1) Georeferencing and processing of LIDAR datasets; (2) Structural interpretation to discriminate between faults, fractures, veins, and joint planes using CAD software and RiSCAN Pro; and (3) Building a 3D DFN in GOCAD®. To test the validity of this workflow, we focus here on a 4.5 m displacement strike-slip fault zone that displays a complex polymodal fracture network in the inter-layered basalt-volcaniclastic sequence, which is well-constrained by field study. The DFN models support our initial field-based hypothesis that fault zone geometry varies with increasing displacement through volcaniclastic units. Fracture concentration appears to be greatest in the upper lava unit, decreases into the volcaniclastic sediments, and decreases further into the lower lava unit. This distribution of fractures appears to be related to the width of the fault zone and the amount of fault damage on the outcrop. For instance, the fault zone is thicker in

  11. 3D modelling of the Austroalpine-Penninic collisional wedge of the NW Alps: dataset management and preliminary results

    Monopoli, Bruno; Bistacchi, Andrea; Bertolo, Davide; Dal Piaz, Giovanni; Gouffon, Yves; Massironi, Matteo; Sartori, Mario; Vittorio Dal Piaz, Giorgio


    We know since the beginning of the 20th century, thanks to mapping and structural studies by the Italian Regio Servizio Geologico (Franchi et al., 1908) and Argand's work (1909; 1911; 1916), that the Austroalpine-Penninic collisional wedge of the NW Alps is spectacularly exposed across the Aosta Valley and Valais ranges (Italy and Switzerland). In the 150th anniversary of the first ascent to Ruskin's "most noble cliff in Europe" - the Cervino/Matterhorn (Whymper, July 14th 1865), first described in a geological profile by Giordano (1869) and in a detailed map by Gerlach (1869; 1871), we have seen the conclusion of very detailed mapping projects carried out in the last years over the two regions, with collaborative efforts across the Italy-Switzerland border, constellated by 4000 m-high peaks. These projects have pictured with an unprecedented detail (up to 1:10.000 scale) the geology of this complex region, resulting from pre-Alpine events, Alpine subduction- and collision-related ductile deformations, and finally late-Alpine brittle deformations from the Oligocene to the Present. Based on this dataset, we use up-to-date technology and software to undertake a 3D modelling study aimed at: i) reconstructing the 3D geometry of the principal tectonic units, ii) detecting and unravelling problems and incongruences in the 2D geometrical models, iii) modelling the kinematics of the Oligocene and Miocene brittle fault network using 2D and 3D balancing and palinspastic restoration techniques. In this contribution we mainly discuss the prerequisites of the project. Common geomodelling paradigms (mainly developed for the hydrocarbon industry) cannot be applied in this project due to (i) the little scale, (ii) the source of the data - fieldwork, and (iii) the polyphase ductile and brittle deformations in the metamorphic nappe stack. Our goals at the moment are to model the post-metamorphic fault network and the boundaries of the principal tectonic units, which will be

  12. Face Recognition using 3D Facial Shape and Color Map Information: Comparison and Combination

    Godil, Afzal; Grother, Patrick


    In this paper, we investigate the use of 3D surface geometry for face recognition and compare it to one based on color map information. The 3D surface and color map data are from the CAESAR anthropometric database. We find that the recognition performance is not very different between 3D surface and color map information using a principal component analysis algorithm. We also discuss the different techniques for the combination of the 3D surface and color map information for multi-modal recognition by using different fusion approaches and show that there is significant improvement in results. The effectiveness of various techniques is compared and evaluated on a dataset with 200 subjects in two different positions.

  13. Modeling 3D Fracture Network in Carbonate NFR: Contribution from an Analogue Dataset, the Cante Perdrix Quarry, Calvisson, SE France

    Gauthier, B.D.M.; Bisdom, K.; Bertotti, G.


    The full 3D characterization of fracture networks is a key issue in naturally fractured reservoir modeling. Fracture geometry (e.g., orientation, size, spacing), fracture scale (e.g., bed-confined fractures, fracture corridors), lateral and vertical variations, need to be defined from limited, gener

  14. 3D Modeling of Iran and Surrounding Areas from Simultaneous Inversion of Multiple Geophysical Datasets (Postprint). Annual Report 3


    of-the-art inversion techniques suffer from poor resolution and nonuniqueness , especially when a single surface-wave mode is used (Huang et al...seismic analyses and to provide adequate starting models for 3D waveform inversion approaches. ACKNOWLEDGEMENTS We thank the scientists, engineers

  15. Comparison of physical quality assurance between Scanora 3D and 3D Accuitomo 80 dental CT scanners

    Ahmed S. Ali


    Full Text Available Background: The use of cone beam computed tomography (CBCT in dentistry has proven to be useful in the diagnosis and treatment planning of several oral and maxillofacial diseases. The quality of the resulting image is dictated by many factors related to the patient, unit, and operator. Materials and methods: In this work, two dental CBCT units, namely Scanora 3D and 3D Accuitomo 80, were assessed and compared in terms of quantitative effective dose delivered to specific locations in a dosimetry phantom. Resolution and contrast were evaluated in only 3D Accuitomo 80 using special quality assurance phantoms. Results: Scanora 3D, with less radiation time, showed less dosing values compared to 3D Accuitomo 80 (mean 0.33 mSv, SD±0.16 vs. 0.18 mSv, SD±0.1. Using paired t-test, no significant difference was found in Accuitomo two scan sessions (p>0.05, while it was highly significant in Scanora (p>0.05. The modulation transfer function value (at 2 lp/mm, in both measurements, was found to be 4.4%. The contrast assessment of 3D Accuitomo 80 in the two measurements showed few differences, for example, the grayscale values were the same (SD=0 while the noise level was slightly different (SD=0 and 0.67, respectively. Conclusions: The radiation dose values in these two CBCT units are significantly less than those encountered in systemic CT scans. However, the dose seems to be affected more by changing the field of view rather than the voltage or amperage. The low doses were at the expense of the image quality produced, which was still acceptable. Although the spatial resolution and contrast were inferior to the medical images produced in systemic CT units, the present results recommend adopting CBCTs in maxillofacial imaging because of low radiation dose and adequate image quality.

  16. Integration of multi-source and multi-scale datasets for 3D structural modeling for subsurface exploration targeting, Luanchuan Mo-polymetallic district, China

    Wang, Gongwen; Ma, Zhenbo; Li, Ruixi; Song, Yaowu; Qu, Jianan; Zhang, Shouting; Yan, Changhai; Han, Jiangwei


    In this paper, multi-source (geophysical, geochemical, geological and remote sensing) datasets were used to construct multi-scale (district-, deposit-, and orebody-scale) 3D geological models and extract 3D exploration criteria for subsurface Mo-polymetallic exploration targeting in the Luanchuan district in China. The results indicate that (i) a series of region-/district-scale NW-trending thrusts controlled main Mo-polymetallic forming, and they were formed by regional Indosinian Qinling orogenic events, the secondary NW-trending district-scale folds and NE-trending faults and the intrusive stock structure are produced based on thrust structure in Caledonian-Indosinian orogenic events; they are ore-bearing zones and ore-forming structures; (ii) the NW-trending district-scale and NE-trending deposit-scale normal faults were crossed and controlled by the Jurassic granite stocks in 3D space, they are associated with the magma-skarn Mo polymetallic mineralization (the 3D buffer distance of ore-forming granite stocks is 600 m) and the NW-trending hydrothermal Pb-Zn deposits which are surrounded by the Jurassic granite stocks and constrained by NW-trending or NE-trending faults (the 3D buffer distance of ore-forming fault is 700 m); and (iii) nine Mo polymetallic and four Pb-Zn targets were identified in the subsurface of the Luanchuan district.

  17. Comparison Between Two Generic 3d Building Reconstruction Approaches - Point Cloud Based VS. Image Processing Based

    Dahlke, D.; Linkiewicz, M.


    This paper compares two generic approaches for the reconstruction of buildings. Synthesized and real oblique and vertical aerial imagery is transformed on the one hand into a dense photogrammetric 3D point cloud and on the other hand into photogrammetric 2.5D surface models depicting a scene from different cardinal directions. One approach evaluates the 3D point cloud statistically in order to extract the hull of structures, while the other approach makes use of salient line segments in 2.5D surface models, so that the hull of 3D structures can be recovered. With orders of magnitudes more analyzed 3D points, the point cloud based approach is an order of magnitude more accurate for the synthetic dataset compared to the lower dimensioned, but therefor orders of magnitude faster, image processing based approach. For real world data the difference in accuracy between both approaches is not significant anymore. In both cases the reconstructed polyhedra supply information about their inherent semantic and can be used for subsequent and more differentiated semantic annotations through exploitation of texture information.

  18. 3D-QSAR modelling dataset of bioflavonoids for predicting the potential modulatory effect on P-glycoprotein activity

    Pathomwat Wongrattanakamon


    Full Text Available The data is obtained from exploring the modulatory activities of bioflavonoids on P-glycoprotein function by ligand-based approaches. Multivariate Linear-QSAR models for predicting the induced/inhibitory activities of the flavonoids were created. Molecular descriptors were initially used as independent variables and a dependent variable was expressed as pFAR. The variables were then used in MLR analysis by stepwise regression calculation to build the linear QSAR data. The entire dataset consisted of 23 bioflavonoids was used as a training set. Regarding the obtained MLR QSAR model, R of 0.963, R2=0.927, Radj2=0.900, SEE=0.197, F=33.849 and q2=0.927 were achieved. The true predictabilities of QSAR model were justified by evaluation with the external dataset (Table 4. The pFARs of representative flavonoids were predicted by MLR QSAR modelling. The data showed that internal and external validations may generate the same conclusion.

  19. Comparison of 3D TOF-MRA and 3D CE-MRA at 3 T for imaging of intracranial aneurysms

    Cirillo, Mario, E-mail: [Department of Medical, Surgical, Neurological, Metabolic and Aging Sciences – 2nd University of Naples (Italy); Scomazzoni, Francesco [Department of Neuroradiology, Scientific Institute San Raffaele, Milan (Italy); Cirillo, Luigi [IRCCS – Institute of Neurological Sciences, Bologna (Italy); Cadioli, Marcello; Simionato, Franco; Iadanza, Antonella [Department of Neuroradiology, Scientific Institute San Raffaele, Milan (Italy); Kirchin, Miles [Worldwide Medical and Regulatory Affairs, Bracco Imaging SpA, Milan (Italy); Righi, Claudio; Anzalone, Nicoletta [Department of Neuroradiology, Scientific Institute San Raffaele, Milan (Italy)


    Purpose: To compare 3 T elliptical-centric CE MRA with 3 T TOF MRA for the detection and characterization of unruptured intracranial aneurysms (UIAs), by using digital subtracted angiography (DSA) as reference. Materials and methods: Twenty-nine patients (12 male, 17 female; mean age: 62 years) with 41 aneurysms (34 saccular, 7 fusiform; mean diameter: 8.85 mm [range 2.0–26.4 mm]) were evaluated with MRA at 3 T each underwent 3D TOF-MRA examination without contrast and then a 3D contrast-enhanced (CE-MRA) examination with 0.1 mmol/kg bodyweight gadobenate dimeglumine and k-space elliptic mapping (Contrast ENhanced Timing Robust Angiography [CENTRA]). Both TOF and CE-MRA images were used to evaluate morphologic features that impact the risk of rupture and the selection of a treatment. Almost half (20/41) of UIAs were located in the internal carotid artery, 7 in the anterior communicating artery, 9 in the middle cerebral artery and 4 in the vertebro-basilar arterial system. All patients also underwent DSA before or after the MR examination. Results: The CE-MRA results were in all cases consistent with the DSA dataset. No differences were noted between 3D TOF-MRA and CE-MRA concerning the detection and location of the 41 aneurysms or visualization of the parental artery. Differences were apparent concerning the visualization of morphologic features, especially for large aneurysms (>13 mm). An irregular sac shape was demonstrated for 21 aneurysms on CE-MRA but only 13/21 aneurysms on 3D TOF-MRA. Likewise, CE-MRA permitted visualization of an aneurismal neck and calculation of the sac/neck ratio for all 34 aneurysms with a neck demonstrated at DSA. Conversely, a neck was visible for only 24/34 aneurysms at 3D TOF-MRA. 3D CE-MRA detected 15 aneurysms with branches originating from the sac and/or neck, whereas branches were recognized in only 12/15 aneurysms at 3D TOF-MRA. Conclusion: For evaluation of intracranial aneurysms at 3 T, 3D CE-MRA is superior to 3D TOF

  20. Validation and Comparison of 2D and 3D Codes for Nearshore Motion of Long Waves Using Benchmark Problems

    Velioǧlu, Deniz; Cevdet Yalçıner, Ahmet; Zaytsev, Andrey


    Tsunamis are huge waves with long wave periods and wave lengths that can cause great devastation and loss of life when they strike a coast. The interest in experimental and numerical modeling of tsunami propagation and inundation increased considerably after the 2011 Great East Japan earthquake. In this study, two numerical codes, FLOW 3D and NAMI DANCE, that analyze tsunami propagation and inundation patterns are considered. Flow 3D simulates linear and nonlinear propagating surface waves as well as long waves by solving three-dimensional Navier-Stokes (3D-NS) equations. NAMI DANCE uses finite difference computational method to solve 2D depth-averaged linear and nonlinear forms of shallow water equations (NSWE) in long wave problems, specifically tsunamis. In order to validate these two codes and analyze the differences between 3D-NS and 2D depth-averaged NSWE equations, two benchmark problems are applied. One benchmark problem investigates the runup of long waves over a complex 3D beach. The experimental setup is a 1:400 scale model of Monai Valley located on the west coast of Okushiri Island, Japan. Other benchmark problem is discussed in 2015 National Tsunami Hazard Mitigation Program (NTHMP) Annual meeting in Portland, USA. It is a field dataset, recording the Japan 2011 tsunami in Hilo Harbor, Hawaii. The computed water surface elevation and velocity data are compared with the measured data. The comparisons showed that both codes are in fairly good agreement with each other and benchmark data. The differences between 3D-NS and 2D depth-averaged NSWE equations are highlighted. All results are presented with discussions and comparisons. Acknowledgements: Partial support by Japan-Turkey Joint Research Project by JICA on earthquakes and tsunamis in Marmara Region (JICA SATREPS - MarDiM Project), 603839 ASTARTE Project of EU, UDAP-C-12-14 project of AFAD Turkey, 108Y227, 113M556 and 213M534 projects of TUBITAK Turkey, RAPSODI (CONCERT_Dis-021) of CONCERT

  1. The next chapter in experimental petrology: Metamorphic dehydration of polycrystalline gypsum captured in 3D microtomographic time series datasets

    Bedford, John; Fusseis, Florian; Leclere, Henry; Wheeler, John; Faulkner, Dan


    Nucleation and growth of new minerals in response to disequilibrium is the most fundamental metamorphic process. However, our current kinetic models of metamorphic reactions are largely based on inference from fossil mineral assemblages, rather than from direct observation. The experimental investigation of metamorphism has also been limited, typically to concealed vessels that restrict the possibility of direct microstructural monitoring. Here we present one of the first time series datasets that captures a metamorphic reaction, dehydration of polycrystalline gypsum to form hemihydrate, in a series of three dimensional x-ray microtomographic datasets. We achieved this by installing an x-ray transparent hydrothermal cell (Fusseis et al., 2014, J. Synchrotron Rad. 21, 251-253) in the microtomography beamline 2BM at the Advanced Photon Source (USA). In the cell, we heated a millimetre-sized sample of Volterra Alabaster to 388 K while applying an effective pressure of 5 MPa. Using hard x-rays that penetrate the pressure vessel, we imaged the specimen 40 times while it reacted for approximately 10 hours. Each microtomographic dataset was acquired in 300 seconds without interrupting the reaction. Our absorption microtomographic data have a voxel size of 1.3 μm, which suffices to analyse the reaction progress in 4D. Gypsum can clearly be distinguished from hemihydrate and pores, which form due to the large negative solid volume change. On the resolved scale, the first hemihydrate needles appear after about 2 hours. Our data allow tracking of individual needles throughout the entire experiment. We quantified their growth rates by measuring their circumference. While individual grains grow at different rates, they all start slowly during the initial nucleation stage, then accelerate and grow steadily between about 200 and 400 minutes before reaction rate decelerates again. Hemihydrate needles are surrounded by porous haloes, which grow with the needles, link up and

  2. Comparison and validation of gridded precipitation datasets for Spain

    Quintana-Seguí, Pere; Turco, Marco; Míguez-Macho, Gonzalo


    In this study, two gridded precipitation datasets are compared and validated in Spain: the recently developed SAFRAN dataset and the Spain02 dataset. These are validated using rain gauges and they are also compared to the low resolution ERA-Interim reanalysis. The SAFRAN precipitation dataset has been recently produced, using the SAFRAN meteorological analysis, which is extensively used in France (Durand et al. 1993, 1999; Quintana-Seguí et al. 2008; Vidal et al., 2010) and which has recently been applied to Spain (Quintana-Seguí et al., 2015). SAFRAN uses an optimal interpolation (OI) algorithm and uses all available rain gauges from the Spanish State Meteorological Agency (Agencia Estatal de Meteorología, AEMET). The product has a spatial resolution of 5 km and it spans from September 1979 to August 2014. This dataset has been produced mainly to be used in large scale hydrological applications. Spain02 (Herrera et al. 2012, 2015) is another high quality precipitation dataset for Spain based on a dense network of quality-controlled stations and it has different versions at different resolutions. In this study we used the version with a resolution of 0.11°. The product spans from 1971 to 2010. Spain02 is well tested and widely used, mainly, but not exclusively, for RCM model validation and statistical downscliang. ERA-Interim is a well known global reanalysis with a spatial resolution of ˜79 km. It has been included in the comparison because it is a widely used product for continental and global scale studies and also in smaller scale studies in data poor countries. Thus, its comparison with higher resolution products of a data rich country, such as Spain, allows us to quantify the errors made when using such datasets for national scale studies, in line with some of the objectives of the EU-FP7 eartH2Observe project. The comparison shows that SAFRAN and Spain02 perform similarly, even though their underlying principles are different. Both products are largely

  3. A User-oriented Comparison of the Techniques for 3D Spectroscopy

    Alighieri, S S


    A comparison of the most popular techniques for 3D spectroscopy is presented in a way which should hopefully be useful for astronomers intending to use these techniques. Integral field spectroscopy, slitless spectroscopy, tunable imaging filters, imaging Fourier transform spectroscopy, and energy-resolving detectors are included in their different implementation. Their relative advantages and disadvantages are discussed in view of the possible scientific application.

  4. Methods to improve the resolution of prestack migrated images, with application to a 3D dataset from a fractured reservoir

    Perez, Gabriel

    I present three different methods to achieve increased definition in images from conventional seismic data, as illustrated with 3D data from the Fort Worth Basin's Barnett Shale fractured reservoir play, currently one of the hottest exploration and production trends in continental U.S. First, I present a method to correct for wavelet stretch in common-angle prestack migrated data. Wavelet stretch adversely influences contributions to the image from large angle or long offset data. Increasing the fidelity of large angles improves the vertical and lateral resolution in images from seismic data and from derived attributes, and positively impact AVA/AVO analysis. Achieving the greatest potential of this technique demands that I address the increased sensitivity to velocity errors and anisotropy. The other two methods presented here benefit from the balance in spectral content of the imaged data across angles and the increased resolution that are achieved from correcting for wavelet stretch. Then I introduce a new way to define azimuth binning in Kirchhoff prestack migration. This approach avoids mixing the typically weaker side-scattered energy with the stronger reflections from the sagittal plane. With the modified binning, signal and noise events are preferentially imaged in azimuth orientations normal to their apparent strike orientation, in surface- or map-views. This modified azimuthal binning also results in improved detection of out-of-the-plane steeply dipping reflectors, fractures and faults and their orientation, especially when combined with attributes such as curvature and coherence. Finally, I present an approach to measure lateral misalignment in prestack migrated seismic images and then correct for it by applying a warping procedure to these images. Though velocity errors are the most likely source for misalignment between images, it can also result from other imperfections in the imaging procedure. Lateral misalignment is most easily recognized and

  5. Development and comparison of projection and image space 3D nodule insertion techniques

    Robins, Marthony; Solomon, Justin; Sahbaee, Pooyan; Samei, Ehsan


    This study aimed to develop and compare two methods of inserting computerized virtual lesions into CT datasets. 24 physical (synthetic) nodules of three sizes and four morphologies were inserted into an anthropomorphic chest phantom (LUNGMAN, KYOTO KAGAKU). The phantom was scanned (Somatom Definition Flash, Siemens Healthcare) with and without nodules present, and images were reconstructed with filtered back projection and iterative reconstruction (SAFIRE) at 0.6 mm slice thickness using a standard thoracic CT protocol at multiple dose settings. Virtual 3D CAD models based on the physical nodules were virtually inserted (accounting for the system MTF) into the nodule-free CT data using two techniques. These techniques include projection-based and image-based insertion. Nodule volumes were estimated using a commercial segmentation tool (iNtuition, TeraRecon, Inc.). Differences were tested using paired t-tests and R2 goodness of fit between the virtually and physically inserted nodules. Both insertion techniques resulted in nodule volumes very similar to the real nodules (<3% difference) and in most cases the differences were not statistically significant. Also, R2 values were all <0.97 for both insertion techniques. These data imply that these techniques can confidently be used as a means of inserting virtual nodules in CT datasets. These techniques can be instrumental in building hybrid CT datasets composed of patient images with virtually inserted nodules.

  6. Dosimetric Comparison of 3D Tangential Radiotherapy of Post-Lumpectomy Breast at Two Different Energies

    Robab Anbiaee


    Full Text Available Introduction: Radiation therapy following breast conserving surgery is one of the most common procedures performed in any radiation oncology department. A tangential parallel-opposed pair is almost always the technique of choice for this purpose. This technique is often performed based on 3D treatment planning. The aim of this study was to compare 3D treatment planning for two different energies (Cobalt 60 versus 6 MV photon beams in tangential irradiation of breast conserving radiotherapy. In this comparison, homogeneity of isodoses within the breast volume and dose received by lungs were considered. Materials and Methods: In this study, twenty patients with breast cancer treated with conservative surgery were included. A CT scan was performed on selected patients. Three-dimensional treatment planning with 6 MV photon beams was carried out for patients on the  Eclipse 3D treatment planning system (TPS. The volumes receiving lower than 95% (Vol105 (hot areas of the reference dose, and the volume of lung receiving ≥30Gy (Vol≥30Gy were derived from dose volume histograms (DVHs. Dose homogeneity index was calculated as: DHI = 100 – (Vol>105 + Vol


    S. Troisi


    Full Text Available In marine biology the shape, morphology, texture and dimensions of the shells and organisms like sponges and gorgonians are very important parameters. For example, a particular type of gorgonian grows every year only few millimeters; this estimation was conducted without any measurement instrument but it has been provided after successive observational studies, because this organism is very fragile: the contact could compromise its structure and outliving. Non-contact measurement system has to be used to preserve such organisms: the photogrammetry is a method capable to assure high accuracy without contact. Nevertheless, the achievement of a 3D photogrammetric model of complex object (as gorgonians or particular shells is a challenge in normal environments, either with metric camera or with consumer camera. Indeed, the successful of automatic target-less image orientation and the image matching algorithms is strictly correlated to the object texture properties and of camera calibration quality as well. In the underwater scenario, the environment conditions strongly influence the results quality; in particular, water’s turbidity, the presence of suspension, flare and other optical aberrations decrease the image quality reducing the accuracy and increasing the noise on the 3D model. Furthermore, seawater density variability influences its refraction index and consequently the interior orientation camera parameters. For this reason, the camera calibration has to be performed in the same survey conditions. In this paper, a comparison between the 3D models of a Charonia Tritonis shell are carried out through surveys conducted both in dry and underwater environments.

  8. Accurate 3D comparison of complex topography with terrestrial laser scanner: application to the Rangitikei canyon (N-Z)

    Lague, Dimitri; Leroux, Jérôme


    Surveying techniques such as Terrestrial Laser Scanner have recently been used to measure surface changes via 3D point cloud (PC) comparison. Two types of approaches have been pursued: 3D tracking of homologous parts of the surface to compute a displacement field, and distance calculation between two point clouds when homologous parts cannot be defined. This study deals with the second approach, typical of natural surfaces altered by erosion, sedimentation or vegetation between surveys. Current comparison methods are based on a closest point distance or require at least one of the PC to be meshed with severe limitations when surfaces present roughness elements at all scales. We introduce a new algorithm performing a direct comparison of point clouds in 3D. Surface normals are first estimated in 3D at a scale consistent with the local surface roughness. The measurement of the mean change along the normal direction is then performed with an explicit calculation of a confidence interval. Comparison with existing...

  9. Comparison of Failure Modes in 2-D and 3-D Woven Carbon Phenolic Systems

    Rossman, Grant A.; Stackpoole, Mairead; Feldman, Jay; Venkatapathy, Ethiraj; Braun, Robert D.


    failure modes because z-fibers in the through-thickness direction provided extra reinforcement to hold material layers together. Therefore, the benefit of using a 3D weave architecture was shown to alleviate failure modes experienced by a 2D laminate sample of similar material composition. In summary this poster reviews the thermal response performance comparisons drawn between a 3D Woven TPS sample and 2D Carbon Phenolic samples after performing rigorous heating experiments in the mARC facility at NASA Ames. Although the mARC Facility is still in its developmental stages, researchers expect similar trends in failure modes observed from large scale arc jet facilities. This work helps demonstrate the viability of 3D Woven TPSs as a new TPS option for future atmospheric entry missions.

  10. Comparison between 3D model of Pisciarelli area (Campi Flegrei caldera) through Terrestrial Laser Scanner

    Caputo, Teresa; Somma, Renato; Marino, Ermanno; Terracciano, Rosario; Troise, Claudia; De Natale, Giuseppe


    The volcanic/geothermal area of Pisciarelli is located within Campi Flegrei caldera .This last is a densely populated area, including the Pozzuoli town and bordering the western side of the Naples city, this causes a high vulnerability and consequently a high volcanic risk. In the recent decades this area has experienced minor ground uplift episodes accompanied by low magnitude seismicity and by strong intensification of degassing activity in particular localized at Pisciarelli area. We present the results of the Terrestrial Laser Scanner (TLS), using a Reigl VZ1000®, analysis of Pisciarelli area performed in June 2013 and the comparison with the data acquired later in March 2014. We apply the TLS technique based on Time of Flight (TOF) method in order to define an accurate 3D digital model for detailed analysis of this area performing numerous scans from different points of view in the area. In this ways was ensured a good coverage of the whole investigated area in order to avoid shaded portion due to the high soil degassing activity. Such fact limits the capacity of laser penetration is caused by wavelength near infrared range. For each survey was obtained a Digital Terrain Model (DTM) from the reconstructed data and both were compared. In particular, we have identified two "critical" areas of interest that will be monitored more frequently. These are: 1) in the lower part of the studied area a major fault line that bounding the Agnano caldera moderately NE-dipping; 2) in the upper part of the study area a zone of depletion with its zone of accumulation. The DTM were georeferenced into the UTM-WGS84 reference frame. The aim of this work is to define a procedure to compare between 3D model applied to monitoring of this area. Also to evaluate of volumetric and morphologic changes and to recognizing unstable masses by comparison of 3D data. For this purpose other TLS surveys will be performed in the upcoming in this active volcanic/geothermal area.


    Rerabek, Martin; Ebrahimi, Touradj


    Currently, the large majority of 3D display solutions rely on binocular perception phenomena. Furthermore, while 3D display technologies are already widely available for cinema and home or corporate use, only a few portable devices currently feature 3D display capabilities. In this paper, we study the alternative methods for restitution of 3D images on displays of commercially available portable devices and analyse their respective performance. This particularly includes the restitution metho...

  12. Mobile 3D rotational X-ray: comparison with CT in sinus surgery

    Carelsen, B. [Dept. of Medical Physics, Academic Medical Center, Amsterdam (Netherlands); Bakker, N.H. [Dept. of Man-Machine Systems, Delft Univ. of Technology, Delft (Netherlands); Boon, S.N. [General X-ray Surgery, Philips Medical Systems, Best (Netherlands); Fokkens, W.J. [ENT Dept., Academic Medical Center, Amsterdam (Netherlands); Freling, N.J.M. [Radiology Dept., Academic Medical Center, Amsterdam (Netherlands); Noordhoek, N.J. [X-ray Pre-development, Philips Medical Systems, Best (Netherlands)


    Clinical evaluation of a 3D rotational X-ray (3D-RX) system, comprising a modified Philips BV Pulsera C-arm system and a Philips 3D-RA workstation, demonstrates good diagnostic accuracy in functional endoscopic sinus surgery.

  13. Comparisons of Several Evaporation/Precipitation Datasets for the Bohai Sea Based on Salinity Simulation

    MAO Xinyan; JIANG Wensheng


    Evaporation (E) rate and precipitation (P) rate are two significant meteorological elements required in the ocean baroclinic modeling as external forcings. However, there are some uncertainties in the currently used E/P rates datasets, especially in terms of the data quality. In this study, we collected E/P rates data from ERA-40, NCEP/NCAR Reanalysis, HOAPS for the Bohai Sea and nine routine stations around Laizhou Bay, and made comparisons among them. It was found that the differences in E/P rates between land and sea are remarkable, which was due to the difference in underlying surfaces. Therefore, the traditional way of using E/P rates acquired on land directly at sea is not correct. Since no final conclusion has been reached concerning the net water transport between the Bohai Sea and the Yellow Sea, it is unfeasible to judge the adequacy of the four kinds of data by using the water budget equation. However, the E/P rates at ERA-40 sea points were considered to be the optimal in terms of temporal/spatial coverage and resolution for the hindcast of salinity variation in the Bohai Sea. Besides, using the 3-D hydrodynamic model HAMSOM (HAMburg Shelf Ocean Model), we performed numerical experiments with different E/P datasets and found that the E/P rates at sea points from ERA-40 dataset are better than those from NCEP/NCAR Reanalysis dataset. If NCEP/NCAR Reanalysis E/P rates are to be used,they need to be adjusted and tested prior to simulation so that more close-to-reality salinity values can be reproduced.

  14. Biological insights from topology independent comparison of protein 3D structures.

    Nguyen, Minh N; Madhusudhan, M S


    Comparing and classifying the three-dimensional (3D) structures of proteins is of crucial importance to molecular biology, from helping to determine the function of a protein to determining its evolutionary relationships. Traditionally, 3D structures are classified into groups of families that closely resemble the grouping according to their primary sequence. However, significant structural similarities exist at multiple levels between proteins that belong to these different structural families. In this study, we propose a new algorithm, CLICK, to capture such similarities. The method optimally superimposes a pair of protein structures independent of topology. Amino acid residues are represented by the Cartesian coordinates of a representative point (usually the C(α) atom), side chain solvent accessibility, and secondary structure. Structural comparison is effected by matching cliques of points. CLICK was extensively benchmarked for alignment accuracy on four different sets: (i) 9537 pair-wise alignments between two structures with the same topology; (ii) 64 alignments from set (i) that were considered to constitute difficult alignment cases; (iii) 199 pair-wise alignments between proteins with similar structure but different topology; and (iv) 1275 pair-wise alignments of RNA structures. The accuracy of CLICK alignments was measured by the average structure overlap score and compared with other alignment methods, including HOMSTRAD, MUSTANG, Geometric Hashing, SALIGN, DALI, GANGSTA(+), FATCAT, ARTS and SARA. On average, CLICK produces pair-wise alignments that are either comparable or statistically significantly more accurate than all of these other methods. We have used CLICK to uncover relationships between (previously) unrelated proteins. These new biological insights include: (i) detecting hinge regions in proteins where domain or sub-domains show flexibility; (ii) discovering similar small molecule binding sites from proteins of different folds and (iii

  15. Evaluation of failing hemodialysis fistulas with multidetector CT angiography: Comparison of different 3D planes

    Karadeli, E. [Department of Radiology, Baskent University, Faculty of Medicine, Ankara (Turkey); Tarhan, N.C. [Department of Radiology, Baskent University, Faculty of Medicine, Ankara (Turkey)], E-mail:; Ulu, E.M. Kayahan; Tutar, N.U. [Department of Radiology, Baskent University, Faculty of Medicine, Ankara (Turkey); Basaran, O. [Department of General Surgery, Baskent University, Faculty of Medicine, Ankara (Turkey); Coskun, M.; Niron, E.A. [Department of Radiology, Baskent University, Faculty of Medicine, Ankara (Turkey)


    Purpose: To evaluate failing hemodialysis fistula complications using 16-detector MDCTA, and to assess the accuracies of different 3D planes. Materials and methods: Thirty patients (16 men, 14 women, aged 27-79 years) were referred for hemodialysis access dysfunction. Thirty-one MDCTA exams were done prior to fistulography. For MDCTA, contrast was administered (2 mL/kg at 5 mL/s) via a peripheral vein in the contralateral arm. Axial MIP, coronal MIP, and VRT images were constructed. Venous complications were evaluated on axial source images, on each 3D plane, and on all-planes together. Results were analyzed using McNemar test. Results: Axial MIP, VRT and all-planes evaluations were most sensitive for fistula site detection (93%). Coronal MIP had the highest sensitivity, specificity and accuracy (35%, 96%, and 85%, respectively) for detecting venous stenosis. VRT and all-planes had the highest sensitivity and accuracy for detecting aneurysms (100%). All-planes and axial MIP were most sensitive for detecting venous occlusion (61% and 54%). Comparisons of detection frequencies for each venous pathology between the five categories of MDCTA revealed no significant differences (P > 0.05). MDCTA additionally showed 3 partially thrombosed aneurysms, 4 anastomosis site stenosis and 12 arterial complications. Conclusion: MDCTA overall gives low sensitivity for detection of central vein stenosis and moderate sensitivity for occlusion. For most pathology, all-planes evaluation of MDCTA gives highest sensitivity and accuracy rates when compared to other planes. For venous stenosis and occlusion, MDCTA should be considered when ultrasonography and fistulography are inconclusive. MDCTA is helpful in identifying aneurysms, collaterals, partial venous thromboses and additional arterial, anastomosis site pathologies.

  16. In-air versus underwater comparison of 3D reconstruction accuracy using action sport cameras.

    Bernardina, Gustavo R D; Cerveri, Pietro; Barros, Ricardo M L; Marins, João C B; Silvatti, Amanda P


    Action sport cameras (ASC) have achieved a large consensus for recreational purposes due to ongoing cost decrease, image resolution and frame rate increase, along with plug-and-play usability. Consequently, they have been recently considered for sport gesture studies and quantitative athletic performance evaluation. In this paper, we evaluated the potential of two ASCs (GoPro Hero3+) for in-air (laboratory) and underwater (swimming pool) three-dimensional (3D) motion analysis as a function of different camera setups involving the acquisition frequency, image resolution and field of view. This is motivated by the fact that in swimming, movement cycles are characterized by underwater and in-air phases what imposes the technical challenge of having a split volume configuration: an underwater measurement volume observed by underwater cameras and an in-air measurement volume observed by in-air cameras. The reconstruction of whole swimming cycles requires thus merging of simultaneous measurements acquired in both volumes. Characterizing and optimizing the instrumental errors of such a configuration makes mandatory the assessment of the instrumental errors of both volumes. In order to calibrate the camera stereo pair, black spherical markers placed on two calibration tools, used both in-air and underwater, and a two-step nonlinear optimization were exploited. The 3D reconstruction accuracy of testing markers and the repeatability of the estimated camera parameters accounted for system performance. For both environments, statistical tests were focused on the comparison of the different camera configurations. Then, each camera configuration was compared across the two environments. In all assessed resolutions, and in both environments, the reconstruction error (true distance between the two testing markers) was less than 3mm and the error related to the working volume diagonal was in the range of 1:2000 (3×1.3×1.5m(3)) to 1:7000 (4.5×2.2×1.5m(3)) in agreement with the

  17. 3D representations of amino acids—applications to protein sequence comparison and classification

    Jie Li


    Full Text Available The amino acid sequence of a protein is the key to understanding its structure and ultimately its function in the cell. This paper addresses the fundamental issue of encoding amino acids in ways that the representation of such a protein sequence facilitates the decoding of its information content. We show that a feature-based representation in a three-dimensional (3D space derived from amino acid substitution matrices provides an adequate representation that can be used for direct comparison of protein sequences based on geometry. We measure the performance of such a representation in the context of the protein structural fold prediction problem. We compare the results of classifying different sets of proteins belonging to distinct structural folds against classifications of the same proteins obtained from sequence alone or directly from structural information. We find that sequence alone performs poorly as a structure classifier. We show in contrast that the use of the three dimensional representation of the sequences significantly improves the classification accuracy. We conclude with a discussion of the current limitations of such a representation and with a description of potential improvements.

  18. 3-D microphysical model studies of Arctic denitrification: comparison with observations

    S. Davies


    Full Text Available Simulations of Arctic denitrification using a 3-D chemistry-microphysics transport model are compared with observations for the winters 1994/1995, 1996/1997 and 1999/2000. The model of Denitrification by Lagrangian Particle Sedimentation (DLAPSE couples the full chemical scheme of the 3-D chemical transport model, SLIMCAT, with a nitric acid trihydrate (NAT growth and sedimentation scheme. We use observations from the Microwave Limb Sounder (MLS and Improved Limb Atmospheric Sounder (ILAS satellite instruments, the balloon-borne Michelsen Interferometer for Passive Atmospheric Sounding (MIPAS-B, and the in situ NOy instrument on-board the ER-2. As well as directly comparing model results with observations, we also assess the extent to which these observations are able to validate the modelling approach taken. For instance, in 1999/2000 the model captures the temporal development of denitrification observed by the ER-2 from late January into March. However, in this winter the vortex was already highly denitrified by late January so the observations do not provide a strong constraint on the modelled rate of denitrification. The model also reproduces the MLS observations of denitrification in early February 2000. In 1996/1997 the model captures the timing and magnitude of denitrification as observed by ILAS, although the lack of observations north of ~67° N make it difficult to constrain the actual timing of onset. The comparison for this winter does not support previous conclusions that denitrification must be caused by an ice-mediated process. In 1994/1995 the model notably underestimates the magnitude of denitrification observed during a single balloon flight of the MIPAS-B instrument. Agreement between model and MLS HNO3 at 68 hPa in mid-February 1995 was significantly better. Sensitivity tests show that a 1.5 K overall decrease in vortex temperatures or a factor 4 increase in assumed NAT nucleation rates produce the best

  19. Comparison of 3D turbulence measurements using three staring wind lidars and a sonic anemometer

    Mann, Jakob; Cariou, J.-P.; Courtney, Michael


    Three pulsed lidars were used in staring, non-scanning mode, placed so that their beams crossed close to a 3D sonic anemometer. The goal is to compare lidar volume averaged wind measurement with point measurement reference sensors and to demonstrate the feasibility of performing 3D turbulence...

  20. 3D reconstruction of carotid atherosclerotic plaque: comparison between spatial compound ultrasound models and anatomical models

    Lind, Bo L.; Fagertun, Jens; Wilhjelm, Jens E.;


    This study deals with the creation of 3D models that can work as a tool for discriminating between tissue and background in the development of tissue classification methods. Ten formalin-fixed atherosclerotic carotid plaques removed by endarterectomy were scanned with 3D multi-angle spatial...... compound ultrasound (US) and subsequently sliced and photographed to produce a 3D anatomical data set. Outlines in the ultrasound data were found by means of active contours and combined into 10 3D ultrasound models. The plaque regions of the anatomical photographs were outlined manually and then combined...... into 10 3D anatomical models. The volumes of the anatomical models correlated with the volume found by a water displacement method (r = 0.95), except for an offset. The models were compared in three ways. Visual inspection showed quite good agreement between the models. The volumes of the ultrasound...

  1. 3D volumetry comparison using 3T magnetic resonance imaging between normal and adenoma-containing pituitary glands

    Ernesto Roldan-Valadez


    Full Text Available Background: Computed-assisted three-dimensional data (3D allows for an accurate evaluation of volumes compared with traditional measurements. Aims: An in vitro method comparison between geometric volume and 3D volumetry to obtain reference data for pituitary volumes in normal pituitary glands (PGs and PGs containing adenomas. Design: Prospective, transverse, analytical study. Materials and Methods: Forty-eight subjects underwent brain magnetic resonance imaging (MRI with 3D sequencing for computer-aided volumetry. PG phantom volumes by both methods were compared. Using the best volumetric method, volumes of normal PGs and PGs with adenoma were compared. Statistical analysis used the Bland-Altman method, t-statistics, effect size and linear regression analysis. Results: Method comparison between 3D volumetry and geometric volume revealed a lower bias and precision for 3D volumetry. A total of 27 patients exhibited normal PGs (mean age, 42.07 ± 16.17 years, although length, height, width, geometric volume and 3D volumetry were greater in women than in men. A total of 21 patients exhibited adenomas (mean age 39.62 ± 10.79 years, and length, height, width, geometric volume and 3D volumetry were greater in men than in women, with significant volumetric differences. Age did not influence pituitary volumes on linear regression analysis. Conclusions: Results from the present study showed that 3D volumetry was more accurate than the geometric method. In addition, the upper normal limits of PGs overlapped with lower volume limits during early stage microadenomas.

  2. Active remote sensing of snow using NMM3D/DMRT and comparison with CLPX II airborne data

    Xu, X.; Liang, D.; Tsang, L.; Andreadis, K.M.; Josberger, E.G.; Lettenmaier, D.P.; Cline, D.W.; Yueh, S.H.


    We applied the Numerical Maxwell Model of three-dimensional simulations (NMM3D) in the Dense Media Radiative Theory (DMRT) to calculate backscattering coefficients. The particles' positions are computer-generated and the subsequent Foldy-Lax equations solved numerically. The phase matrix in NMM3D has significant cross-polarization, particularly when the particles are densely packed. The NMM3D model is combined with DMRT in calculating the microwave scattering by dry snow. The NMM3D/DMRT equations are solved by an iterative solution up to the second order in the case of small to moderate optical thickness. The numerical results of NMM3D/DMRT are illustrated and compared with QCA/DMRT. The QCA/DMRT and NMM3D/DMRT results are also applied to compare with data from two specific datasets from the second Cold Land Processes Experiment (CLPX II) in Alaska and Colorado. The data are obtained at the Ku-band (13.95 GHz) observations using airborne imaging polarimetric scatterometer (POLSCAT). It is shown that the model predictions agree with the field measurements for both co-polarization and cross-polarization. For the Alaska region, the average snow depth and snow density are used as the inputs for DMRT. The grain size, selected from within the range of the ground measurements, is used as a best-fit parameter within the range. For the Colorado region, we use the Variable Infiltration Capacity Model (VIC) to obtain the input snow profiles for NMM3D/DMRT. ?? 2010 IEEE.

  3. Chemotherapeutic efficiency of drugs in vitro: Comparison of doxorubicin exposure in 3D and 2D culture matrices.

    Casey, A; Gargotti, M; Bonnier, F; Byrne, H J


    The interest in the use of 3D matrices for in vitro analysis, with a view to increasing the relevance of in vitro studies and reducing the dependence on in vivo studies, has been growing in recent years. Cells grown in a 3D in vitro matrix environment have been reported to exhibit significantly different properties to those in a conventional 2D culture environment. However, comparison of 2D and 3D cell culture models have recently been noted to result in differing responses of cytotoxic assays, without any associated change in viability. The effect was attributed to differing conversion rates and effective concentrations of the resazurin assay in 2D and 3D environments, rather than differences in cellular metabolism. In this study, the efficacy of a chemotherapeutic agent, doxorubicin, is monitored and compared in conventional 2D and 3D collagen gel exposures of immortalized human cervical cells. Viability was monitored with the aid of the Alamar Blue assay and drug internalisation was verified using confocal microscopy. Drug uptake and retention within the collagen matrix was monitored by absorption spectroscopy. The viability studies showed apparent differences between the 2D and 3D culture systems, the differences attributed in part to the physical transition from 2D to a 3D environment causing alterations to dye resazurin uptake and conversion rates. The use of 3D culture matrices has widely been interpreted to result in "reduced" toxicity or cellular "resistance" to the chemotherapeutic agent. The results of this study show that the reduced efficiency of the drug to cells grown in the 3D environment can be accounted for by a sequential reduction of the effective concentration of the test compound and assay. This is due to absorption within the collagen gel inducing a higher uptake of both drug and assay thereby influencing the toxic impact of the drug and conversion rate of resazurin, and. The increased effective surface area of the cell exposed to the drug

  4. 3D digitization methods based on laser excitation and active triangulation: a comparison

    Aubreton, Olivier; Mériaudeau, Fabrice; Truchetet, Frédéric


    3D reconstruction of surfaces is an important topic in computer vision and corresponds to a large field of applications: industrial inspection, reverse engineering, object recognition, biometry, archeology… Because of the large varieties of applications, one can find in the literature a lot of approaches which can be classified into two families: passive and active [1]. Certainly because of their reliability, active approaches, using imaging system with an additional controlled light source, seem to be the most commonly used in the industrial field. In this domain, the 3D digitization approach based on active 3D triangulation has had important developments during the last ten years [2] and seems to be mature today if considering the important number of systems proposed by manufacturers. Unfortunately, the performances of active 3D scanners depend on the optical properties of the surface to digitize. As an example, on Fig 1.a, a 3D shape with a diffuse surface has been digitized with Comet V scanner (Steinbichler). The 3D reconstruction is presented on Fig 1.b. The same experiment was carried out on a similar object (same shape) but presenting a specular surface (Fig 1.c and Fig 1.d) ; it can clearly be observed, that the specularity influences of the performance of the digitization.

  5. Comparison of 2D versus 3D mammography with screening cases: an observer study

    Fernandez, James Reza; Deshpande, Ruchi; Hovanessian-Larsen, Linda; Liu, Brent


    Breast cancer is the most common type of non-skin cancer in women. 2D mammography is a screening tool to aid in the early detection of breast cancer, but has diagnostic limitations of overlapping tissues, especially in dense breasts. 3D mammography has the potential to improve detection outcomes by increasing specificity, and a new 3D screening tool with a 3D display for mammography aims to improve performance and efficiency as compared to 2D mammography. An observer study using human studies collected from was performed to compare traditional 2D mammography with this new 3D mammography technique. A prior study using a mammography phantom revealed no difference in calcification detection, but improved mass detection in 2D as compared to 3D. There was a significant decrease in reading time for masses, calcifications, and normals in 3D compared to 2D, however, as well as more favorable confidence levels in reading normal cases. Data for this current study is currently being obtained, and a full report should be available in the next few weeks.


    G. Bianco


    Full Text Available 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

  7. Comprehensive evaluation of latest 2D/3D monitors and comparison to a custom-built 3D mirror-based display in laparoscopic surgery

    Wilhelm, Dirk; Reiser, Silvano; Kohn, Nils; Witte, Michael; Leiner, Ulrich; Mühlbach, Lothar; Ruschin, Detlef; Reiner, Wolfgang; Feussner, Hubertus


    Though theoretically superior, 3D video systems did not yet achieve a breakthrough in laparoscopic surgery. Furthermore, visual alterations, such as eye strain, diplopia and blur have been associated with the use of stereoscopic systems. Advancements in display and endoscope technology motivated a re-evaluation of such findings. A randomized study on 48 test subjects was conducted to investigate whether surgeons can benefit from using most current 3D visualization systems. Three different 3D systems, a glasses-based 3D monitor, an autostereoscopic display and a mirror-based theoretically ideal 3D display were compared to a state-of-the-art 2D HD system. The test subjects split into a novice and an expert surgeon group, which high experience in laparoscopic procedures. Each of them had to conduct a well comparable laparoscopic suturing task. Multiple performance parameters like task completion time and the precision of stitching were measured and compared. Electromagnetic tracking provided information on the instruments path length, movement velocity and economy. The NASA task load index was used to assess the mental work load. Subjective ratings were added to assess usability, comfort and image quality of each display. Almost all performance parameters were superior for the 3D glasses-based display as compared to the 2D and the autostereoscopic one, but were often significantly exceeded by the mirror-based 3D display. Subjects performed the task at average 20% faster and with a higher precision. Work-load parameters did not show significant differences. Experienced and non-experienced laparoscopists profited equally from 3D. The 3D mirror system gave clear evidence for additional potential of 3D visualization systems with higher resolution and motion parallax presentation.

  8. Comparison of optimized 3D-SPACE and 3D-TSE sequences at 1.5T MRCP in the diagnosis of choledocholithiasis

    Sudholt, P. [University Hospital Marburg (Germany). Dept. of Diagnostic and Interventional Radiology; Zaehringer, C.; Tyndall, A.; Bongartz, G.; Hohmann, J. [University Hospital Basel (Switzerland). Clinic for Radiology and Nuclear Medicine; Urigo, C. [Ars Medica Clinic, Gravesano-Lugano (Switzerland). Radiology


    The aim of the study was to evaluate whether or not MRCP using a 3D-SPACE sequence allows for better image quality and a higher level of diagnostic confidence than a conventional 3D-TSE sequence at 1.5T regarding the diagnosis of choledocholithiasis in a routine clinical setting. 3D-SPACE and 3D-TSE sequences were performed in 42 consecutive patients with suspected choledocholithiasis undergoing MRCP. Evaluation of image quality and diagnostic confidence was done on the pancreaticobiliary tree which was subdivided into 10 segments. They were scored and statistically evaluated separately for visibility and diagnostic certainty by three radiologists with differing levels of experience on a five-point scale of 1 to 5 and -2 to 2, respectively. Student t-test was performed, and the interobserver agreement was also calculated. Image quality for each segment was significantly better for the 3D-SPACE sequence compared to the 3D-TSE sequence (4.48±0.94 vs. 3.98±1.20; 5-point scale p<0.01). Diagnostic confidence for the reporting radiologist was also significantly better for 3D-SPACE than for 3D-TSE (1.68±0.56 vs. 1.46±0.70; 3-point scale; p<0.01). The interobserver agreement was high in both sequences, 0.62-0.83 and 0.64-0.82, respectively. The optimized 3D-SPACE sequence allows for better image quality in 1.5T MRCP examinations and leads to a higher diagnostic confidence for choledocholithiasis compared to the conventional 3D-TSE sequence.

  9. Comparison of Simultaneous and Sequential Two-View Registration for 3D/2D Registration of Vascular Images

    Pathak, Chetna; Van Horn, Mark; Weeks, Susan; Bullitt, Elizabeth


    Accurate 3D/2D vessel registration is complicated by issues of image quality, occlusion, and other problems. This study performs a quantitative comparison of 3D/2D vessel registration in which vessels segmented from preoperative CT or MR are registered with biplane x-ray angiograms by either a) simultaneous two-view registration with advance calculation of the relative pose of the two views, or b) sequential registration with each view. We conclude on the basis of phantom studies that, even i...

  10. Validation of the BISON 3D Fuel Performance Code: Temperature Comparisons for Concentrically and Eccentrically Located Fuel Pellets

    J. D. Hales; D. M. Perez; R. L. Williamson; S. R. Novascone; B. W. Spencer


    BISON is a modern finite-element based nuclear fuel performance code that has been under development at the Idaho National Laboratory (USA) since 2009. The code is applicable to both steady and transient fuel behaviour and is used to analyse either 2D axisymmetric or 3D geometries. BISON has been applied to a variety of fuel forms including LWR fuel rods, TRISO-coated fuel particles, and metallic fuel in both rod and plate geometries. Code validation is currently in progress, principally by comparison to instrumented LWR fuel rods. Halden IFA experiments constitute a large percentage of the current BISON validation base. The validation emphasis here is centreline temperatures at the beginning of fuel life, with comparisons made to seven rods from the IFA-431 and 432 assemblies. The principal focus is IFA-431 Rod 4, which included concentric and eccentrically located fuel pellets. This experiment provides an opportunity to explore 3D thermomechanical behaviour and assess the 3D simulation capabilities of BISON. Analysis results agree with experimental results showing lower fuel centreline temperatures for eccentric fuel with the peak temperature shifted from the centreline. The comparison confirms with modern 3D analysis tools that the measured temperature difference between concentric and eccentric pellets is not an artefact and provides a quantitative explanation for the difference.

  11. A Comparison of Radiation Dose Between Standard and 3D Angiography in Congenital Heart Disease

    Manica, João Luiz Langer, E-mail:; Borges, Mônica Scott; Medeiros, Rogério Fachel de; Fischer, Leandro dos Santos; Broetto, Gabriel; Rossi, Raul Ivo Filho [Instituto de Cardiologia / Fundação Universitária de Cardiologia, Porto Alegre, RS (Brazil)


    The use of three-dimensional rotational angiography (3D-RA) to assess patients with congenital heart diseases appears to be a promising technique despite the scarce literature available. The objective of this study was to describe our initial experience with 3D-RA and to compare its radiation dose to that of standard two-dimensional angiography (2D-SA). Between September 2011 and April 2012, 18 patients underwent simultaneous 3D-RA and 2D-SA during diagnostic cardiac catheterization. Radiation dose was assessed using the dose-area-product (DAP). The median patient age and weight were 12.5 years and 47.5 Kg, respectively. The median DAP of each 3D-RA acquisition was 1093µGy.m{sup 2} and 190µGy.m{sup 2} for each 2D-SA acquisition (p<0.01). In patients weighing more than 45Kg (n=7), this difference was attenuated but still significant (1525 µGy.m{sup 2} vs.413µGy.m{sup 2}, p=0.01). No difference was found between one 3D-RA and three 2D-SA (1525µGy.m{sup 2} vs.1238 µGy.m{sup 2}, p = 0.575) in this population. This difference was significantly higher in patients weighing less than 45Kg (n=9) (713µGy.m{sup 2} vs.81µGy.m{sup 2}, P = 0.008), even when comparing one 3D-RA with three 2D-SA (242µGy.m{sup 2}, respectively, p<0.008). 3D-RA was extremely useful for the assessment of conduits of univentricular hearts, tortuous branches of the pulmonary artery, and aorta relative to 2D-SA acquisitions. The radiation dose of 3D-RA used in our institution was higher than those previously reported in the literature and this difference was more evident in children. This type of assessment is of paramount importance when starting to perform 3D-RA.

  12. Comparison of Tomo-PIV and 3D-PTV for microfluidic flows

    Kim, Hyoungsoo; Westerweel, Jerry; Elsinga, Gerrit E.


    Two 3D-3C velocimetry techniques for micro-scale measurements are compared: tomographic particle image velocimetry (Tomo-PIV) and 3D particle-tracking velocimetry (3D-PTV). Both methods are applied to experimental data from a confined shear-driven liquid droplet over a moving surface. The droplet has 200 μm height and 2 mm diameter. Micro 3D-PTV and Tomo-PIV are used to obtain the tracer particle distribution and the flow velocity field for the same set of images. It is shown that the reconstructed particle distributions are distinctly different, where Tomo-PIV returns a nearly uniform distribution over the height of the volume, as expected, and PTV reveals a clear peak in the particle distribution near the plane of focus. In Tomo-PIV, however, the reconstructed particle peak intensity decreases in proportion to the distance from the plane of focus. Due to the differences in particle distributions, the measured flow velocities are also different. In particular, we observe Tomo-PIV to be in closer agreement with mass conservation. Furthermore, the random noise level is found to increase with distance to the plane of focus at a higher rate for 3D-PTV as compared to Tomo-PIV. Thus, for a given noise threshold value, the latter method can measure reliably over a thicker volume.

  13. Late gadolinium enhancement cardiac imaging on a 3T scanner with parallel RF transmission technique: prospective comparison of 3D-PSIR and 3D-IR

    Schultz, Anthony [Nouvel Hopital Civil, Strasbourg University Hospital, Radiology Department, Strasbourg Cedex (France); Nouvel Hopital Civil, Service de Radiologie, Strasbourg Cedex (France); Caspar, Thibault [Nouvel Hopital Civil, Strasbourg University Hospital, Cardiology Department, Strasbourg Cedex (France); Schaeffer, Mickael [Nouvel Hopital Civil, Strasbourg University Hospital, Public Health and Biostatistics Department, Strasbourg Cedex (France); Labani, Aissam; Jeung, Mi-Young; El Ghannudi, Soraya; Roy, Catherine [Nouvel Hopital Civil, Strasbourg University Hospital, Radiology Department, Strasbourg Cedex (France); Ohana, Mickael [Nouvel Hopital Civil, Strasbourg University Hospital, Radiology Department, Strasbourg Cedex (France); Universite de Strasbourg / CNRS, UMR 7357, iCube Laboratory, Illkirch (France)


    To qualitatively and quantitatively compare different late gadolinium enhancement (LGE) sequences acquired at 3T with a parallel RF transmission technique. One hundred and sixty participants prospectively enrolled underwent a 3T cardiac MRI with 3 different LGE sequences: 3D Phase-Sensitive Inversion-Recovery (3D-PSIR) acquired 5 minutes after injection, 3D Inversion-Recovery (3D-IR) at 9 minutes and 3D-PSIR at 13 minutes. All LGE-positive patients were qualitatively evaluated both independently and blindly by two radiologists using a 4-level scale, and quantitatively assessed with measurement of contrast-to-noise ratio and LGE maximal surface. Statistical analyses were calculated under a Bayesian paradigm using MCMC methods. Fifty patients (70 % men, 56yo ± 19) exhibited LGE (62 % were post-ischemic, 30 % related to cardiomyopathy and 8 % post-myocarditis). Early and late 3D-PSIR were superior to 3D-IR sequences (global quality, estimated coefficient IR > early-PSIR: -2.37 CI = [-3.46; -1.38], prob(coef > 0) = 0 % and late-PSIR > IR: 3.12 CI = [0.62; 4.41], prob(coef > 0) = 100 %), LGE surface estimated coefficient IR > early-PSIR: -0.09 CI = [-1.11; -0.74], prob(coef > 0) = 0 % and late-PSIR > IR: 0.96 CI = [0.77; 1.15], prob(coef > 0) = 100 %. Probabilities for late PSIR being superior to early PSIR concerning global quality and CNR were over 90 %, regardless of the aetiological subgroup. In 3T cardiac MRI acquired with parallel RF transmission technique, 3D-PSIR is qualitatively and quantitatively superior to 3D-IR. (orig.)

  14. Comparison of a unidirectional panoramic 3D endoluminal interpretation technique to traditional 2D and bidirectional 3D interpretation techniques at CT colonography: preliminary observations

    Lenhart, D.K.; Babb, J.; Bonavita, J.; Kim, D. [Department of Radiology, NYU Medical Center, 560 First Avenue, Suite HW-202, New York, NY 10016 (United States); Bini, E.J. [Department of Medicine, NYU School of Medicine, NYU Medical Center, 560 First Avenue, Suite HW-202, New York, NY 10016 (United States); Megibow, A.J. [Department of Radiology, NYU Medical Center, 560 First Avenue, Suite HW-202, New York, NY 10016 (United States); Macari, M., E-mail: michael.macari@med.nyu.ed [Department of Radiology, NYU Medical Center, 560 First Avenue, Suite HW-202, New York, NY 10016 (United States)


    Aim: To compare the evaluation times and accuracy of unidirectional panoramic three-dimensional (3D) endoluminal interpretation to traditional two-dimensional (2D) and bidirectional 3D endoluminal techniques. materials and methods: Sixty-nine patients underwent computed tomography colonography (CTC) after bowel cleansing. Forty-five had no polyps and 24 had at least one polyp >=6 mm. Patients underwent same-day colonoscopy with segmental unblinding. Three experienced abdominal radiologists evaluated the data using one of three primary interpretation techniques: (1) 2D; (2) bidirectional 3D; (3) panoramic 3D. Mixed model analysis of variance and logistic regression for correlated data were used to compare techniques with respect to time and sensitivity and specificity. Results: Mean evaluation times were 8.6, 14.6, and 12.1 min, for 2D, 3D, and panoramic, respectively. 2D was faster than either 3D technique (p < 0.0001), and the panoramic technique was faster than bidirectional 3D (p = 0.0139). The overall sensitivity of each technique per polyp and per patient was 68.4 and 76.7% for 2D, 78.9 and 93.3% for 3D; and 78.9 and 86.7% for panoramic 3D. Conclusion: 2D interpretation was the fastest overall, the panoramic technique was significantly faster than the bidirectional with similar sensitivity and specificity. The sensitivity for a single reader was significantly lower using the 2D technique. Each reader should select the technique with which they are most successful.

  15. Online 3D terrain visualisation using Unity 3D game engine: A comparison of different contour intervals terrain data draped with UAV images

    Hafiz Mahayudin, Mohd; Che Mat, Ruzinoor


    The main objective of this paper is to discuss on the effectiveness of visualising terrain draped with Unmanned Aerial Vehicle (UAV) images generated from different contour intervals using Unity 3D game engine in online environment. The study area that was tested in this project was oil palm plantation at Sintok, Kedah. The contour data used for this study are divided into three different intervals which are 1m, 3m and 5m. ArcGIS software were used to clip the contour data and also UAV images data to be similar size for the overlaying process. The Unity 3D game engine was used as the main platform for developing the system due to its capabilities which can be launch in different platform. The clipped contour data and UAV images data were process and exported into the web format using Unity 3D. Then process continue by publishing it into the web server for comparing the effectiveness of different 3D terrain data (contour data) draped with UAV images. The effectiveness is compared based on the data size, loading time (office and out-of-office hours), response time, visualisation quality, and frame per second (fps). The results were suggest which contour interval is better for developing an effective online 3D terrain visualisation draped with UAV images using Unity 3D game engine. It therefore benefits decision maker and planner related to this field decide on which contour is applicable for their task.

  16. Comparison of 3D turbulence measurements using three staring wind lidars and a sonic anemometer

    Mann, Jakob; Cariou, Jean-Pierre; Courtney, Michael


    to a 3D sonic anemometer mounted at 78 m above the ground. The results show generally very good correlation between the lidar and the sonic times series, except that the variance of the velocity measured by the lidar is attenuated due to spatial filtering. The amount of attenuation can however...

  17. Focus shift impacted by mask 3D and comparison between Att. PSM and OMOG

    Liu, Yansong; Su, Xiaojing; Dong, LiSong; Song, Zhiyang; Guo, Moran; Su, Yajuan; Wei, Yayi


    The impact of mask three dimensions (M3D) effect on lithography processes is getting more pronounced from 32 nm nodes1-2. In this paper, we report four research progresses on the M3Deffect. Firstly, the impacts of M3D effect on the best focus (BF) offset were studied with though pitch as test pattern. The M3D effect has negative impacts on the BF, generating the BF offset pattern by pattern. The BF offset strongly depends on MoSi film thickness (THK). However the impact of MoSi profile, or side wall angle (SWA) could be ignored. Secondly, M3D OPC is needed to mitigate the shift of dose and focus center. Thirdly, as long as enough shade, the thinner MoSi, the less BF shift, as electromagnetic field (EMF) effect makes space behave smaller, which leads to higher contrast but higher mask error enhancement factor(MEEF); So the trade-off between contrast and MEEF is needed. And MoSi THK 43.7 nm in production supposed to be the optimized value from this study. Finally, compared to attenuating phase shifting mask (att.PSM) mask, opaque MoSi on Glass (OMOG) mask is more robust in terms of MEEF, the normalized image logarithmic slope (NILS) etc., not obviously influenced by mask duty ratio.

  18. A Comparison of Iterative 2D-3D Pose Estimation Methods for Real-Time Applications

    Grest, Daniel; Krüger, Volker; Petersen, Thomas


    This work compares iterative 2D-3D Pose Estimation methods for use in real-time applications. The compared methods are available for public as C++ code. One method is part of the openCV library, namely POSIT. Because POSIT is not applicable for planar 3Dpoint congurations, we include the planar...

  19. Comparison of 3 methods on fabricating micro- /nano- structured surface on 3D mold cavity

    Zhang, Yang; Hansen, Hans Nørgaard; Bissacco, Giuliano


    The methods to manufacture micro- or nano- structures on surfaces have been an area of intense investigation. Demands are shown for technologies for surface structuring on real 3D parts in many fields. However, most technologies for the fabrication of micro-structured functional surfaces are stil...

  20. 3D imaging with an isocentric mobile C-arm comparison of image quality with spiral CT.

    Kotsianos, Dorothea; Wirth, Stefan; Fischer, Tanja; Euler, Ekkehard; Rock, Clemens; Linsenmaier, Ulrich; Pfeifer, Klaus Jürgen; Reiser, Maximilian


    The purpose of this study was to evaluate the image quality of the new 3D imaging system (ISO-C-3D) for osteosyntheses of tibial condylar fractures in comparison with spiral CT (CT). Sixteen human cadaveric knees were examined with a C-arm 3D imaging system and spiral computed tomography. Various screws and plates of steel and titanium were used for osteosynthesis in these specimens. Image quality and clinical value of multiplanar (MP) reformatting of both methods were analyzed. In addition, five patients with tibial condylar fractures were examined for diagnosis and intra-operative control. The image quality of the C-arm 3D imaging system in the cadaveric study was rated as significantly worse than that of spiral CT with and without prostheses. After implantation of prostheses an increased incidence of artifacts was observed, but the diagnostic accuracy was not affected. Titanium implants caused the smallest number of artifacts. The image quality of ISO-C is inferior to CT, and metal artifacts were more prominent, but the clinical value was equal. ISO-C-3D can be useful in planning operative reconstructions and can verify the reconstruction of articular surfaces and the position of implants with diagnostic image quality.

  1. 3D imaging with an isocentric mobile C-arm. Comparison of image quality with spiral CT

    Kotsianos, Dorothea; Wirth, Stefan; Fischer, Tanja; Euler, Ekkehard; Rock, Clemens; Linsenmaier, Ulrich; Pfeifer, Klaus Juergen; Reiser, Maximilian [Departments of Radiology and Surgery, Klinikum der Universitaet Muenchen, Innenstadt, Nussbaumstrasse 20, 80336, Munchen (Germany)


    The purpose of this study was to evaluate the image quality of the new 3D imaging system (ISO-C-3D) for osteosyntheses of tibial condylar fractures in comparison with spiral CT (CT). Sixteen human cadaveric knees were examined with a C-arm 3D imaging system and spiral computed tomography. Various screws and plates of steel and titanium were used for osteosynthesis in these specimens. Image quality and clinical value of multiplanar (MP) reformatting of both methods were analyzed. In addition, five patients with tibial condylar fractures were examined for diagnosis and intra-operative control. The image quality of the C-arm 3D imaging system in the cadaveric study was rated as significantly worse than that of spiral CT with and without prostheses. After implantation of prostheses an increased incidence of artifacts was observed, but the diagnostic accuracy was not affected. Titanium implants caused the smallest number of artifacts. The image quality of ISO-C is inferior to CT, and metal artifacts were more prominent, but the clinical value was equal. ISO-C-3D can be useful in planning operative reconstructions and can verify the reconstruction of articular surfaces and the position of implants with diagnostic image quality. (orig.)

  2. Domestic comparison of radiation treatment techniques for breast cancer: 3D-CRT, IMRT and VMAT

    Lee, Bo Ram; Yoon, Myong Geun [Dept. of Bio-convergence Engineering, College of Health Science, Korea University, Seoul (Korea, Republic of); Lee, Sun Young [Dept. of Radiation Oncology, Yusung Sun Medical Center, Daejeon (Korea, Republic of)


    The purpose of this study is to compare method in the treatment of breast cancer using dose index. And, it is to find the optimized treatment technique to the patient. The phantom filled with tissue-equivalent material were used simulation and treatment as techniques of 3D-CRT, IMRT, VMAT was planned using Eclipse v10. By using HI(homogeneity index), CI(Conformity index), OE (Organ equivalent dose), EAR(Excess Absolute Risk), were assessed for each treatment plans. HI and CI of 3D-CRT, IMRT, VMAT were calculated 16.89, 11.21, 9.55 and 0.59, 0.61, 0.83. The organ average doses of Lt lung, Rt lung, liver, heart, esophagus, cord, Lt breast, trachea and stomach were 0.01 ∼ 2.02 Gy, 0.36 ∼ 5.01 Gy, 0.25 ∼ 2.49 Gy, 0.14 ∼ 6.92 Gy, 0.03 ∼ 2.02 Gy, 0.01 ∼ 1.06 Gy, 0.25 ∼ 6.08 Gy, 0.08 ∼ 0.59 Gy, 0.01 ∼ 1.34 Gy, respectively. The OED, EAR of the IMRT and VMAT show higher than 3D-CRT. As the result of this study, we could confirm being higher dose index(HI, CI) in IMRT and VMAT than 3D-CRT, but doses of around normal organs was higher IMRT, VMAT than 3D-CRT.

  3. Spatial Distribution of Nucleosynthesis Products in Cassiopeia A: Comparison Between Observations and 3D Explosion Models

    Young, Patrick; Timmes, Francis X; Arnett, David; Fryer, Christopher L; Rockefeller, Gabriel; Hungerford, Aimee; Diehl, Steven; Bennett, Michael; Hirschi, Raphael; Pignatari, Marco; Herwig, Falk; Magkotsios, Georgios


    We examine observed heavy element abundances in the Cassiopeia A supernova remnant as a constraint on the nature of the Cas A supernova. We compare bulk abundances from 1D and 3D explosion models and spatial distribution of elements in 3D models with those derived from X-ray observations. We also examine the cospatial production of 26Al with other species. We find that the most reliable indicator of the presence of 26Al in unmixed ejecta is a very low S/Si ratio (~0.05). Production of N in O/S/Si-rich regions is also indicative. The biologically important element P is produced at its highest abundance in the same regions. Proxies should be detectable in supernova ejecta with high spatial resolution multiwavelength observations.

  4. Comparison between 2D and 3D Modelling of Induction Machine Using Finite Element Method

    Zelmira Ferkova


    Full Text Available The paper compares two different ways (2D and 3D of modelling of two-phase squirrel-cage induction machine using the finite element method (FEM. It focuses mainly on differences between starting characteristics given from both types of the model. It also discusses influence of skew rotor slots on harmonic content in air gap flux density and summarizes some issues of both approaches.

  5. Comparison of 2-D and 3-D estimates of placental volume in early pregnancy.

    Aye, Christina Y L; Stevenson, Gordon N; Impey, Lawrence; Collins, Sally L


    Ultrasound estimation of placental volume (PlaV) between 11 and 13 wk has been proposed as part of a screening test for small-for-gestational-age babies. A semi-automated 3-D technique, validated against the gold standard of manual delineation, has been found at this stage of gestation to predict small-for-gestational-age at term. Recently, when used in the third trimester, an estimate obtained using a 2-D technique was found to correlate with placental weight at delivery. Given its greater simplicity, the 2-D technique might be more useful as part of an early screening test. We investigated if the two techniques produced similar results when used in the first trimester. The correlation between PlaV values calculated by the two different techniques was assessed in 139 first-trimester placentas. The agreement on PlaV and derived "standardized placental volume," a dimensionless index correcting for gestational age, was explored with the Mann-Whitney test and Bland-Altman plots. Placentas were categorized into five different shape subtypes, and a subgroup analysis was performed. Agreement was poor for both PlaV and standardized PlaV (p < 0.001 and p < 0.001), with the 2-D technique yielding larger estimates for both indices compared with the 3-D method. The mean difference in standardized PlaV values between the two methods was 0.007 (95% confidence interval: 0.006-0.009). The best agreement was found for regular rectangle-shaped placentas (p = 0.438 and p = 0.408). The poor correlation between the 2-D and 3-D techniques may result from the heterogeneity of placental morphology at this stage of gestation. In early gestation, the simpler 2-D estimates of PlaV do not correlate strongly with those obtained with the validated 3-D technique.



    The use of 3-D computational fluid dynamics (CFD) is proposed to simulate the conjugate conduction-convection of heat transfer problems in eccentric annularfinned tube heat exchangers. The numerical simulation results allow us to evaluate the heat transfer coefficient over fin surfaces, the fin efficiency and the pressure drop. The aim of the present paper is to determine the optimum tube position in the circular fin that maximizes heat dissipation and minimizes pressure drop. In addition, th...

  7. A highly heterogeneous 3D PWR core benchmark: deterministic and Monte Carlo method comparison

    Jaboulay, J.-C.; Damian, F.; Douce, S.; Lopez, F.; Guenaut, C.; Aggery, A.; Poinot-Salanon, C.


    Physical analyses of the LWR potential performances with regards to the fuel utilization require an important part of the work dedicated to the validation of the deterministic models used for theses analyses. Advances in both codes and computer technology give the opportunity to perform the validation of these models on complex 3D core configurations closed to the physical situations encountered (both steady-state and transient configurations). In this paper, we used the Monte Carlo Transport code TRIPOLI-4®; to describe a whole 3D large-scale and highly-heterogeneous LWR core. The aim of this study is to validate the deterministic CRONOS2 code to Monte Carlo code TRIPOLI-4®; in a relevant PWR core configuration. As a consequence, a 3D pin by pin model with a consistent number of volumes (4.3 millions) and media (around 23,000) is established to precisely characterize the core at equilibrium cycle, namely using a refined burn-up and moderator density maps. The configuration selected for this analysis is a very heterogeneous PWR high conversion core with fissile (MOX fuel) and fertile zones (depleted uranium). Furthermore, a tight pitch lattice is selcted (to increase conversion of 238U in 239Pu) that leads to harder neutron spectrum compared to standard PWR assembly. In these conditions two main subjects will be discussed: the Monte Carlo variance calculation and the assessment of the diffusion operator with two energy groups for the core calculation.

  8. Comparison of 2D and 3D Neutron Transport Analyses on Yonggwang Unit 3 Reactor

    Maeng, Aoung Jae; Kim, Byoung Chul; Lim, Mi Joung; Kim, Kyung Sik; Jeon, Young Kyou [Korea Reactor Integrity Surveillance Technology, Daejeon (Korea, Republic of); Yoo, Choon Sung [Korea Atomic Energy Research Institutes, Daejeon (Korea, Republic of)


    10 CFR Part 50 Appendix H requires periodical surveillance program in the reactor vessel (RV) belt line region of light water nuclear power plant to check vessel integrity resulting from the exposure to neutron irradiation and thermal environment. Exact exposure analysis of the neutron fluence based on right modeling and simulations is the most important in the evaluation. Traditional 2 dimensional (D) and 1D synthesis methodologies have been widely applied to evaluate the fast neutron (E > 1.0 MeV) fluence exposure to RV. However, 2D and 1D methodologies have not provided accurate fast neutron fluence evaluation at elevations far above or below the active core region. RAPTOR-M3G (RApid Parallel Transport Of Radiation - Multiple 3D Geometries) program for 3D geometries calculation was therefore developed both by Westinghouse Electronic Company, USA and Korea Reactor Integrity Surveillance Technology (KRIST) for the analysis of In-Vessel Surveillance Test and Ex-Vessel Neutron Dosimetry (EVND). Especially EVND which is installed at active core height between biological shielding material and concrete also evaluates axial neutron fluence by placing three dosimetries each at Top, Middle and Bottom part of the angle representing maximum neutron fluence. The EVND programs have been applied to the Korea Nuclear Plants. The objective of this study is therefore to compare the 3D and the 2D Neutron Transport Calculations and Analyses on the Yonggwang unit 3 Reactor as an example.

  9. Comprehensive comparison of large-scale tissue expression datasets

    Alberto Santos


    Full Text Available For tissues to carry out their functions, they rely on the right proteins to be present. Several high-throughput technologies have been used to map out which proteins are expressed in which tissues; however, the data have not previously been systematically compared and integrated. We present a comprehensive evaluation of tissue expression data from a variety of experimental techniques and show that these agree surprisingly well with each other and with results from literature curation and text mining. We further found that most datasets support the assumed but not demonstrated distinction between tissue-specific and ubiquitous expression. By developing comparable confidence scores for all types of evidence, we show that it is possible to improve both quality and coverage by combining the datasets. To facilitate use and visualization of our work, we have developed the TISSUES resource (, which makes all the scored and integrated data available through a single user-friendly web interface.

  10. Comparison of LDA and SPRT on Clinical Dataset Classifications.

    Lee, Chih; Nkounkou, Brittany; Huang, Chun-Hsi


    In this work, we investigate the well-known classification algorithm LDA as well as its close relative SPRT. SPRT affords many theoretical advantages over LDA. It allows specification of desired classification error rates α and β and is expected to be faster in predicting the class label of a new instance. However, SPRT is not as widely used as LDA in the pattern recognition and machine learning community. For this reason, we investigate LDA, SPRT and a modified SPRT (MSPRT) empirically using clinical datasets from Parkinson's disease, colon cancer, and breast cancer. We assume the same normality assumption as LDA and propose variants of the two SPRT algorithms based on the order in which the components of an instance are sampled. Leave-one-out cross-validation is used to assess and compare the performance of the methods. The results indicate that two variants, SPRT-ordered and MSPRT-ordered, are superior to LDA in terms of prediction accuracy. Moreover, on average SPRT-ordered and MSPRT-ordered examine less components than LDA before arriving at a decision. These advantages imply that SPRT-ordered and MSPRT-ordered are the preferred algorithms over LDA when the normality assumption can be justified for a dataset.

  11. Dosimetric and radiobiologic comparison of 3D conformal versus intensity modulated planning techniques for prostate bed radiotherapy.

    Koontz, Bridget F; Das, Shiva; Temple, Kathy; Bynum, Sigrun; Catalano, Suzanne; Koontz, Jason I; Montana, Gustavo S; Oleson, James R


    Adjuvant radiotherapy for locally advanced prostate cancer improves biochemical and clinical disease-free survival. While comparisons in intact prostate cancer show a benefit for intensity modulated radiation therapy (IMRT) over 3D conformal planning, this has not been studied for post-prostatectomy radiotherapy (RT). This study compares normal tissue and target dosimetry and radiobiological modeling of IMRT vs. 3D conformal planning in the postoperative setting. 3D conformal plans were designed for 15 patients who had been treated with IMRT planning for salvage post-prostatectomy RT. The same computed tomography (CT) and target/normal structure contours, as well as prescription dose, was used for both IMRT and 3D plans. Normal tissue complication probabilities (NTCPs) were calculated based on the dose given to the bladder and rectum by both plans. Dose-volume histogram and NTCP data were compared by paired t-test. Bladder and rectal sparing were improved with IMRT planning compared to 3D conformal planning. The volume of the bladder receiving at least 75% (V75) and 50% (V50) of the dose was significantly reduced by 28% and 17%, respectively (p = 0.002 and 0.037). Rectal dose was similarly reduced, V75 by 33% and V50 by 17% (p = 0.001 and 0.004). While there was no difference in the volume of rectum receiving at least 65 Gy (V65), IMRT planning significant reduced the volume receiving 40 Gy or more (V40, p = 0.009). Bladder V40 and V65 were not significantly different between planning modalities. Despite these dosimetric differences, there was no significant difference in the NTCP for either bladder or rectal injury. IMRT planning reduces the volume of bladder and rectum receiving high doses during post-prostatectomy RT. Because of relatively low doses given to the bladder and rectum, there was no statistically significant improvement in NTCP between the 3D conformal and IMRT plans.

  12. Comparison of Supernovae Datasets Constraints on Dark Energy

    ZHANG Cheng-Wu; XU Li-Xin; CHANG Bao-Rong; LIU Hong-Ya


    Cosmological measurements suggest that our universe contains a dark energy component. In order to study the dark energy evolution, we constrain a parameterized dark energy equation of state ω(z) = ω0+ω1(z/1+z) using the recent observational datasets: 157 Gold type la supernovae and the newly released 182 Gold type la supernovae by the maximum likelihood method. It is found that the best fit ω(z) crosses -1 in the past and the present best fit value of ω(0)<-1 obtained from 157 Gold-type la supernovae. The crossing of -1 is not realized and ω0=-1 is not ruled out in 1σ confidence level for the 182 Gold-type la supernovae. It is also found that the range of parameter ω0 is wide even in 1σ confidence level and the best fit ω(z) is sensitive to the prior of Ωm.

  13. TU-CD-207-04: Radiation Exposure Comparisons of CESM with 2D FFDM and 3D Tomosynthesis Mammography

    James, J; Boltz, T; Pavlicek, W [Mayo Clinic Arizona, Scottsdale, AZ (United States)


    Purpose: While mammography is considered the standard for front-line breast cancer screening, image sensitivity and specificity can be affected by factors like dense breast tissue. Contrast-enhanced spectral mammography (CESM) shows promising initial results for dense breasts but comes at the cost of increased dose compared with full-field-digital-mammography (FFDM). The goal of this study is to quantitatively assess the dose increase of CESM in comparison with 2D-FFDM and 3D-Tomo at varying breast thickness. Methods: The experiments were conducted on a Hologic-Selenia-Dimensions system that performed 2D-FFDM, 3D-Tomo and CESM (high and low energies) on regular (50/50) and dense (70/30) breast tissue-mimicking phantoms. Both the phantoms had 6, 1-cm thick slabs (total thickness 6cm), compressed at 20-lbs using an 18×24 paddle. A single exposure was performed for each of the 3 mammo techniques with the following settings: AEC-Auto; Focal Spot-Large; kVp-Auto; mAs- Auto, Target/Filter combination-Auto; AEC Sensor/Exposure compensation Step-2/0. Average glandular dose (AGD) in mGy was obtained and compared as a function of breast thickness (1 – 6 cm) for both the phantom types. Results: The study shows that dose from the total CESM from 50/50 phantom at a breast thickness of a) 4.5 cm was 37.5% higher than 2D-FFDM and 30% higher than 3D-Tomo, b) 6 cm was 36.2% higher than 2D-FFDM and 41% higher than 3D-Tomo. For a dense breast tissue of 70/30 phantom, it was found that CESM dose at a breast thickness of: a) 4.5 cm was 33.3% higher than 2D-FFDM and 28.8% higher than 3D-Tomo, b) 6 cm was 35.4% higher than 2D-FFDM and 48.0% higher than 3D-Tomo. The overall CESM dose for the dense breast phantom was 12.5% higher at 4.5cm and 35% higher at 6 cm compared to the 50/50 phantom. Conclusion: This quantitative comparison study showed that CESM technique has an increased radiation dose compared to conventional 2D-FFDM and 3D-Tomo.

  14. Generation and Comparison of Tls and SFM Based 3d Models of Solid Shapes in Hydromechanic Research

    Zhang, R.; Schneider, D.; Strauß, B.


    The aim of a current study at the Institute of Hydraulic Engineering and Technical Hydromechanics at TU Dresden is to develop a new injection method for quick and economic sealing of dikes or dike bodies, based on a new synthetic material. To validate the technique, an artificial part of a sand dike was built in an experimental hall. The synthetic material was injected, which afterwards spreads in the inside of the dike. After the material was fully solidified, the surrounding sand was removed with an excavator. In this paper, two methods, which applied terrestrial laser scanning (TLS) and structure from motion (SfM) respectively, for the acquisition of a 3D point cloud of the remaining shapes are described and compared. Combining with advanced software packages, a triangulated 3D model was generated and subsequently the volume of vertical sections of the shape were calculated. As the calculation of the volume revealed differences between the TLS and the SfM 3D model, a thorough qualitative comparison of the two models will be presented as well as a detailed accuracy assessment. The main influence of the accuracy is caused by generalisation in case of gaps due to occlusions in the 3D point cloud. Therefore, improvements for the data acquisition with TLS and SfM for such kind of objects are suggested in the paper.


    R. Zhang


    Full Text Available The aim of a current study at the Institute of Hydraulic Engineering and Technical Hydromechanics at TU Dresden is to develop a new injection method for quick and economic sealing of dikes or dike bodies, based on a new synthetic material. To validate the technique, an artificial part of a sand dike was built in an experimental hall. The synthetic material was injected, which afterwards spreads in the inside of the dike. After the material was fully solidified, the surrounding sand was removed with an excavator. In this paper, two methods, which applied terrestrial laser scanning (TLS and structure from motion (SfM respectively, for the acquisition of a 3D point cloud of the remaining shapes are described and compared. Combining with advanced software packages, a triangulated 3D model was generated and subsequently the volume of vertical sections of the shape were calculated. As the calculation of the volume revealed differences between the TLS and the SfM 3D model, a thorough qualitative comparison of the two models will be presented as well as a detailed accuracy assessment. The main influence of the accuracy is caused by generalisation in case of gaps due to occlusions in the 3D point cloud. Therefore, improvements for the data acquisition with TLS and SfM for such kind of objects are suggested in the paper.

  16. Comparison of User Performance with Interactive and Static 3d Visualization - Pilot Study

    Herman, L.; Stachoň, Z.


    Interactive 3D visualizations of spatial data are currently available and popular through various applications such as Google Earth, ArcScene, etc. Several scientific studies have focused on user performance with 3D visualization, but static perspective views are used as stimuli in most of the studies. The main objective of this paper is to try to identify potential differences in user performance with static perspective views and interactive visualizations. This research is an exploratory study. An experiment was designed as a between-subject study and a customized testing tool based on open web technologies was used for the experiment. The testing set consists of an initial questionnaire, a training task and four experimental tasks. Selection of the highest point and determination of visibility from the top of a mountain were used as the experimental tasks. Speed and accuracy of each task performance of participants were recorded. The movement and actions in the virtual environment were also recorded within the interactive variant. The results show that participants deal with the tasks faster when using static visualization. The average error rate was also higher in the static variant. The findings from this pilot study will be used for further testing, especially for formulating of hypotheses and designing of subsequent experiments.

  17. Comparison of parabolic filtration methods for 3D filtered back projection in pulsed EPR imaging.

    Qiao, Zhiwei; Redler, Gage; Epel, Boris; Halpern, Howard J


    Pulse electron paramagnetic resonance imaging (Pulse EPRI) is a robust method for noninvasively measuring local oxygen concentrations in vivo. For 3D tomographic EPRI, the most commonly used reconstruction algorithm is filtered back projection (FBP), in which the parabolic filtration process strongly influences image quality. In this work, we designed and compared 7 parabolic filtration methods to reconstruct both simulated and real phantoms. To evaluate these methods, we designed 3 error criteria and 1 spatial resolution criterion. It was determined that the 2 point derivative filtration method and the two-ramp-filter method have unavoidable negative effects resulting in diminished spatial resolution and increased artifacts respectively. For the noiseless phantom the rectangular-window parabolic filtration method and sinc-window parabolic filtration method were found to be optimal, providing high spatial resolution and small errors. In the presence of noise, the 3 point derivative method and Hamming-window parabolic filtration method resulted in the best compromise between low image noise and high spatial resolution. The 3 point derivative method is faster than Hamming-window parabolic filtration method, so we conclude that the 3 point derivative method is optimal for 3D FBP.

  18. Bronchial morphometry in smokers: comparison with healthy subjects by using 3D CT

    Montaudon, Michel [Unite d' Imagerie Thoracique, CHU de Bordeaux, Pessac (France); Universite Bordeaux 2, Laboratoire de Physiologie Cellulaire Respiratoire, Bordeaux (France); INSERM, Bordeaux (France); Hopital Cardiologique, Unite d' Imagerie Thoracique, Pessac (France); Berger, Patrick; Marthan, Roger [Universite Bordeaux 2, Laboratoire de Physiologie Cellulaire Respiratoire, Bordeaux (France); INSERM, Bordeaux (France); Service d' Exploration Fonctionnelle Respiratoire, CHU de Bordeaux, Pessac (France); Lederlin, Mathieu [Unite d' Imagerie Thoracique, CHU de Bordeaux, Pessac (France); Tunon-de-Lara, Jose Manuel [Universite Bordeaux 2, Laboratoire de Physiologie Cellulaire Respiratoire, Bordeaux (France); INSERM, Bordeaux (France); Service des Maladies Respiratoires, CHU de Bordeaux, Pessac (France); Laurent, Francois [Unite d' Imagerie Thoracique, CHU de Bordeaux, Pessac (France); Universite Bordeaux 2, Laboratoire de Physiologie Cellulaire Respiratoire, Bordeaux (France); INSERM, Bordeaux (France)


    The assessment of airway dimensions in patients with airway disease by using computed tomography (CT) has been limited by the obliquity of bronchi, the ability to identify the bronchial generation, and the limited number of bronchial measurements. The aims of the present study were (i) to analyze cross-sectional bronchial dimensions after automatic orthogonal reconstruction of all visible bronchi on CT images, and (ii) to compare bronchial morphometry between smokers and nonsmokers. CT and pulmonary function tests were performed in 18 males separated into two groups: 9 nonsmokers and 9 smokers. Bronchial wall area (WA) and lumen area (LA) were assessed using dedicated 3D software able to provide accurate cross-sectional measurements of all visible bronchi on CT. WA/LA and WA/(WA+LA) ratios were computed and all parameters were compared between both groups. Smokers demonstrated greater WA, smaller LA, and consequently greater LA/WA and LA/(WA+LA) ratios than nonsmokers. These differences occurred downward starting at the fourth bronchial generation. 3D quantitative CT method is able to demonstrate significant changes in bronchial morphometry related to tobacco consumption. (orig.)

  19. A Comparison of Splitting Techniques for 3D Complex Padé Fourier Finite Difference Migration

    Jessé C. Costa


    Full Text Available Three-dimensional wave-equation migration techniques are still quite expensive because of the huge matrices that need to be inverted. Several techniques have been proposed to reduce this cost by splitting the full 3D problem into a sequence of 2D problems. We compare the performance of splitting techniques for stable 3D Fourier finite-difference (FFD migration techniques in terms of image quality and computational cost. The FFD methods are complex Padé FFD and FFD plus interpolation, and the compared splitting techniques are two- and four-way splitting as well as alternating four-way splitting, that is, splitting into the coordinate directions at one depth and the diagonal directions at the next depth level. From numerical examples in homogeneous and inhomogeneous media, we conclude that, though theoretically less accurate, alternate four-way splitting yields results of comparable quality as full four-way splitting at the cost of two-way splitting.

  20. Comparison between the 3D numerical simulation and experiment of the bubble near different boundaries


    Based on the potential flow theory, the vortex ring is introduced to simulate the toroidal bubble, and the boundary element method is applied to simulate the evo- lution of the bubble. Elastic-plasticity of structure being taken into account, the interaction between the bubble and the elastic-plastic structure is computed by combining the boundary element method (BEM) and the finite element method (FEM), and a corresponding 3D computing program is developed. This program is used to simulate the three-dimensional bubble dynamics in free field, near wall and near the elastic-plastic structure, and the numerical results are compared with the existing experimental results. The error is within 10%. The effects of different boundaries upon the bubble dynamics are presented by studying the bubble dy- namics near different boundaries.

  1. Magnetotelluric 3-D inversion—a review of two successful workshops on forward and inversion code testing and comparison

    Miensopust, Marion P.; Queralt, Pilar; Jones, Alan G.; 3D MT modellers


    Over the last half decade the need for, and importance of, three-dimensional (3-D) modelling of magnetotelluric (MT) data have increased dramatically and various 3-D forward and inversion codes are in use and some have become commonly available. Comparison of forward responses and inversion results is an important step for code testing and validation prior to `production' use. The various codes use different mathematical approximations to the problem (finite differences, finite elements or integral equations), various orientations of the coordinate system, different sign conventions for the time dependence and various inversion strategies. Additionally, the obtained results are dependent on data analysis, selection and correction as well as on the chosen mesh, inversion parameters and regularization adopted, and therefore, a careful and knowledge-based use of the codes is essential. In 2008 and 2011, during two workshops at the Dublin Institute for Advanced Studies over 40 people from academia (scientists and students) and industry from around the world met to discuss 3-D MT inversion. These workshops brought together a mix of code writers as well as code users to assess the current status of 3-D modelling, to compare the results of different codes, and to discuss and think about future improvements and new aims in 3-D modelling. To test the numerical forward solutions, two 3-D models were designed to compare the responses obtained by different codes and/or users. Furthermore, inversion results of these two data sets and two additional data sets obtained from unknown models (secret models) were also compared. In this manuscript the test models and data sets are described (supplementary files are available) and comparisons of the results are shown. Details regarding the used data, forward and inversion parameters as well as computational power are summarized for each case, and the main discussion points of the workshops are reviewed. In general, the responses

  2. Deriving 3d Point Clouds from Terrestrial Photographs - Comparison of Different Sensors and Software

    Niederheiser, Robert; Mokroš, Martin; Lange, Julia; Petschko, Helene; Prasicek, Günther; Oude Elberink, Sander


    Terrestrial photogrammetry nowadays offers a reasonably cheap, intuitive and effective approach to 3D-modelling. However, the important choice, which sensor and which software to use is not straight forward and needs consideration as the choice will have effects on the resulting 3D point cloud and its derivatives. We compare five different sensors as well as four different state-of-the-art software packages for a single application, the modelling of a vegetated rock face. The five sensors represent different resolutions, sensor sizes and price segments of the cameras. The software packages used are: (1) Agisoft PhotoScan Pro (1.16), (2) Pix4D (2.0.89), (3) a combination of Visual SFM (V0.5.22) and SURE (, and (4) MicMac (1.0). We took photos of a vegetated rock face from identical positions with all sensors. Then we compared the results of the different software packages regarding the ease of the workflow, visual appeal, similarity and quality of the point cloud. While PhotoScan and Pix4D offer the user-friendliest workflows, they are also "black-box" programmes giving only little insight into their processing. Unsatisfying results may only be changed by modifying settings within a module. The combined workflow of Visual SFM, SURE and CloudCompare is just as simple but requires more user interaction. MicMac turned out to be the most challenging software as it is less user-friendly. However, MicMac offers the most possibilities to influence the processing workflow. The resulting point-clouds of PhotoScan and MicMac are the most appealing.

  3. Breast Density Analysis with Automated Whole-Breast Ultrasound: Comparison with 3-D Magnetic Resonance Imaging.

    Chen, Jeon-Hor; Lee, Yan-Wei; Chan, Si-Wa; Yeh, Dah-Cherng; Chang, Ruey-Feng


    In this study, a semi-automatic breast segmentation method was proposed on the basis of the rib shadow to extract breast regions from 3-D automated whole-breast ultrasound (ABUS) images. The density results were correlated with breast density values acquired with 3-D magnetic resonance imaging (MRI). MRI images of 46 breasts were collected from 23 women without a history of breast disease. Each subject also underwent ABUS. We used Otsu's thresholding method on ABUS images to obtain local rib shadow information, which was combined with the global rib shadow information (extracted from all slice projections) and integrated with the anatomy's breast tissue structure to determine the chest wall line. The fuzzy C-means classifier was used to extract the fibroglandular tissues from the acquired images. Whole-breast volume (WBV) and breast percentage density (BPD) were calculated in both modalities. Linear regression was used to compute the correlation of density results between the two modalities. The consistency of density measurement was also analyzed on the basis of intra- and inter-operator variation. There was a high correlation of density results between MRI and ABUS (R(2) = 0.798 for WBV, R(2) = 0.825 for PBD). The mean WBV from ABUS images was slightly smaller than the mean WBV from MR images (MRI: 342.24 ± 128.08 cm(3), ABUS: 325.47 ± 136.16 cm(3), p MRI: 24.71 ± 15.16%, ABUS: 28.90 ± 17.73%, p breast density measurement variation between the two modalities. Our results revealed a high correlation in WBV and BPD between MRI and ABUS. Our study suggests that ABUS provides breast density information useful in the assessment of breast health.

  4. Electrical resistivity tomography applied to a complex lava dome: 2D and 3D models comparison

    Portal, Angélie; Fargier, Yannick; Lénat, Jean-François; Labazuy, Philippe


    interpretation. Geometry and location of ERT profiles on the Puy de Dôme volcano allow to compute 3D inversion models of the electrical resistivity distribution with a new inversion code. This code uses tetrahedrons to discretize the 3D model and uses also a conventional Gauss-Newton inversion scheme combined to an Occam regularisation to process the data. It allows to take into account all the data information and prevents the construction of 3D artefacts present in conventional 2D inversion results. Inversion results show a strong electrical resistivity heterogeneity of the entire dome. Underlying volcanic edifices are clearly identified below the lava dome. Generally speaking, the flanks of the volcano show high resistivity values, and the summit part is more conductive but also very heterogeneous.

  5. Comparison of plasma data from ASPERA-3/Mars-Express with a 3-D hybrid simulation

    A. Bößwetter


    Full Text Available The ELS and IMA sensors of the ASPERA-3 experiment onboard of Mars-Express (MEX can measure electron as well as ion moments. We compare these measurements for a specific orbit with the simulation results from a 3-D hybrid model. In the hybrid approximation the electrons are modeled as a massless charge-neutralizing fluid, whereas the ions are treated as individual particles. This approach allows gyroradius effects to be included in our model calculations of the Martian plasma environment because the gyroradii of the solar wind protons are in the range of several hundred kilometers and therefore comparable with the characteristic scales of the subsolar ionospheric interaction region. The position of both the bow shock and the Ion Composition Boundary (ICB manifest in the MEX data as well as in the results from the hybrid simulation nearly at the same location. The characteristic features of these boundaries, i.e. an increase of proton density and temperature at the Bow Shock and a transition from solar wind to ionospheric particles at the ICB, are clearly identifiable in the data.




    Full Text Available The use of 3-D computational fluid dynamics (CFD is proposed to simulate the conjugate conduction-convection of heat transfer problems in eccentric annularfinned tube heat exchangers. The numerical simulation results allow us to evaluate the heat transfer coefficient over fin surfaces, the fin efficiency and the pressure drop. The aim of the present paper is to determine the optimum tube position in the circular fin that maximizes heat dissipation and minimizes pressure drop. In addition, this study analyzes the effects of fin spacing and fin tube diameter on heat transfer and flow characteristics for a range of Reynolds numbers, 4500≤Re≤22500. A satisfactory qualitative and quantitative agreement was obtained between the numerical predictions and the results published in the literature. For small fin spacings, the eccentric annular finned tube is more efficient than the concentric one. Among the cases examined, the average heat transfer coefficient of the eccentric annular-finned tube, for a tube shift St =12 mm and a Reynolds number Re = 9923, was 7.61% greater than that of the concentric one. This gain is associated with a 43.09% reduction in pressure drop.

  7. Comparison of steroid substrates and inhibitors of P-glycoprotein by 3D-QSAR analysis

    Li, Yan; Wang, Yong-Hua; Yang, Ling; Zhang, Shu-Wei; Liu, Chang-Hou; Yang, Sheng-Li


    Steroid derivatives show a complex interaction with P-glycoprotein (Pgp). To determine the essential structural requirements of a series of structurally related and functionally diverse steroids for Pgp-mediated transport or inhibition, a three-dimensional quantitative structure activity relationship study was performed by comparative similarity index analysis modeling. Twelve models have been explored to well correlate the physiochemical features with their biological functions with Pgp on basis of substrate and inhibitor datasets, in which the best predictive model for substrate gave cross-validated q2=0.720, non-cross-validated r2=0.998, standard error of estimate SEE=0.012, F=257.955, and the best predictive model for inhibitor gave q2=0.536, r2=0.950, SEE=1.761 and F=45.800. The predictive ability of all models was validated by a set of compounds that were not included in the training set. The physiochemical similarities and differences of steroids as Pgp substrate and inhibitor, respectively, were analyzed to be helpful in developing new steroid-like compounds.

  8. Comparison of fast 3D simulation and actinic inspection for EUV masks with buries defects

    Clifford, C. H.; Wiraatmadja, S.; Chan, T. T.; Neureuther, A. R.; Goldberg, K. A.; Mochi, I.; Liang, T.


    Aerial images for isolated defects and the interactions of defects with features are compared between the Actinic Inspection Tool (AIT) at Lawrence Berkeley National Laboratory (LBNL) and the fast EUV simulation program RADICAL. Comparisons between AIT images from August 2007 and RADICAL simulations are used to extract aberrations. At this time astigmatism was the dominant aberration with a value of 0.55 waves RMS. Significant improvements in the imaging performance of the AIT were made between August 2007 and December 2008. A good match will be shown between the most recent AIT images and RADICAL simulations without aberrations. These comparisons will demonstrate that a large defect, in this case 7nm tall on the surface, is still printable even if it is centered under the absorber line. These comparisons also suggest that the minimum defect size is between 1.5nm and 0.8nm surface height because a 1.5nm defect was printable but a 0.8nm was not. Finally, the image of a buried defect near an absorber line through focus will demonstrate an inversion in the effect of the defect from a protrusion of the dark line into the space to a protrusion of the space into the line.

  9. Comparison of Phase-Based 3D Near-Field Source Localization Techniques for UHF RFID.

    Parr, Andreas; Miesen, Robert; Vossiek, Martin


    In this paper, we present multiple techniques for phase-based narrowband backscatter tag localization in three-dimensional space with planar antenna arrays or synthetic apertures. Beamformer and MUSIC localization algorithms, known from near-field source localization and direction-of-arrival estimation, are applied to the 3D backscatter scenario and their performance in terms of localization accuracy is evaluated. We discuss the impact of different transceiver modes known from the literature, which evaluate different send and receive antenna path combinations for a single localization, as in multiple input multiple output (MIMO) systems. Furthermore, we propose a new Singledimensional-MIMO (S-MIMO) transceiver mode, which is especially suited for use with mobile robot systems. Monte-Carlo simulations based on a realistic multipath error model ensure spatial correlation of the simulated signals, and serve to critically appraise the accuracies of the different localization approaches. A synthetic uniform rectangular array created by a robotic arm is used to evaluate selected localization techniques. We use an Ultra High Frequency (UHF) Radiofrequency Identification (RFID) setup to compare measurements with the theory and simulation. The results show how a mean localization accuracy of less than 30 cm can be reached in an indoor environment. Further simulations demonstrate how the distance between aperture and tag affects the localization accuracy and how the size and grid spacing of the rectangular array need to be adapted to improve the localization accuracy down to orders of magnitude in the centimeter range, and to maximize array efficiency in terms of localization accuracy per number of elements.

  10. Comparison of Phase-Based 3D Near-Field Source Localization Techniques for UHF RFID

    Andreas Parr


    Full Text Available In this paper, we present multiple techniques for phase-based narrowband backscatter tag localization in three-dimensional space with planar antenna arrays or synthetic apertures. Beamformer and MUSIC localization algorithms, known from near-field source localization and direction-of-arrival estimation, are applied to the 3D backscatter scenario and their performance in terms of localization accuracy is evaluated. We discuss the impact of different transceiver modes known from the literature, which evaluate different send and receive antenna path combinations for a single localization, as in multiple input multiple output (MIMO systems. Furthermore, we propose a new Singledimensional-MIMO (S-MIMO transceiver mode, which is especially suited for use with mobile robot systems. Monte-Carlo simulations based on a realistic multipath error model ensure spatial correlation of the simulated signals, and serve to critically appraise the accuracies of the different localization approaches. A synthetic uniform rectangular array created by a robotic arm is used to evaluate selected localization techniques. We use an Ultra High Frequency (UHF Radiofrequency Identification (RFID setup to compare measurements with the theory and simulation. The results show how a mean localization accuracy of less than 30 cm can be reached in an indoor environment. Further simulations demonstrate how the distance between aperture and tag affects the localization accuracy and how the size and grid spacing of the rectangular array need to be adapted to improve the localization accuracy down to orders of magnitude in the centimeter range, and to maximize array efficiency in terms of localization accuracy per number of elements.

  11. Comparison of a 3-D GPU-Assisted Maxwell Code and Ray Tracing for Reflectometry on ITER

    Gady, Sarah; Kubota, Shigeyuki; Johnson, Irena


    Electromagnetic wave propagation and scattering in magnetized plasmas are important diagnostics for high temperature plasmas. 1-D and 2-D full-wave codes are standard tools for measurements of the electron density profile and fluctuations; however, ray tracing results have shown that beam propagation in tokamak plasmas is inherently a 3-D problem. The GPU-Assisted Maxwell Code utilizes the FDTD (Finite-Difference Time-Domain) method for solving the Maxwell equations with the cold plasma approximation in a 3-D geometry. Parallel processing with GPGPU (General-Purpose computing on Graphics Processing Units) is used to accelerate the computation. Previously, we reported on initial comparisons of the code results to 1-D numerical and analytical solutions, where the size of the computational grid was limited by the on-board memory of the GPU. In the current study, this limitation is overcome by using domain decomposition and an additional GPU. As a practical application, this code is used to study the current design of the ITER Low Field Side Reflectometer (LSFR) for the Equatorial Port Plug 11 (EPP11). A detailed examination of Gaussian beam propagation in the ITER edge plasma will be presented, as well as comparisons with ray tracing. This work was made possible by funding from the Department of Energy for the Summer Undergraduate Laboratory Internship (SULI) program. This work is supported by the US DOE Contract No.DE-AC02-09CH11466 and DE-FG02-99-ER54527.

  12. Frontonasal dysmorphology in bipolar disorder by 3D laser surface imaging and geometric morphometrics: comparisons with schizophrenia.

    Hennessy, Robin J


    Any developmental relationship between bipolar disorder and schizophrenia engenders continuing debate. As the brain and face emerge in embryological intimacy, brain dysmorphogenesis is accompanied by facial dysmorphogenesis. 3D laser surface imaging was used to capture the facial surface of 13 male and 14 female patients with bipolar disorder in comparison with 61 male and 75 female control subjects and with 37 male and 32 female patients with schizophrenia. Surface images were analysed using geometric morphometrics and 3D visualisations to identify domains of facial shape that distinguish bipolar patients from controls and bipolar patients from those with schizophrenia. Both male and female bipolar patients evidenced significant facial dysmorphology: common to male and female patients was overall facial widening, increased width of nose, narrowing of mouth and upward displacement of the chin; dysmorphology differed between male and female patients for nose length, lip thickness and tragion height. There were few morphological differences in comparison with schizophrenia patients. That dysmorphology of the frontonasal prominences and related facial regions in bipolar disorder is more similar to than different from that found in schizophrenia indicates some common dysmorphogenesis. Bipolar disorder and schizophrenia might reflect similar insult(s) acting over slightly differing time-frames or slightly differing insult(s) acting over a similar time-frame.

  13. Qualitative and quantitative assessment of wrist MRI at 3.0T - Comparison between isotropic 3D turbo spin echo and isotropic 3D fast field echo and 2D turbo spin echo

    Jung, Jee Young [Dept. of Radiology, Chungang Univ. Hospital, School of Medicine, Chungang Univ. (Korea, Republic of); Yoon, Young Cheol [Dept. of Radiology, Samsung Medical Center, School of Medicine, Sungkyunkwan Univ. (Korea, Republic of)], e-mail:; Jung, Jin Young [Dept. of Radiology, Saint Paul' s Hospital, The Catholic Univ. (Korea, Republic of); Choe, Bong-Keun [Dept. of Preventive Medicine, School of Medicine, Kyung Hee Univ., Seoul (Korea, Republic of)


    Background: Isotropic three-dimensional (3D) magnetic resonance imaging (MRI) has been applied to various joints. However, comparison for image quality between isotropic 3D MRI and two-dimensional (2D) turbo spin echo (TSE) sequence of the wrist at a 3T MR system has not been investigated. Purpose: To compare the image quality of isotropic 3D MRI including TSE intermediate-weighted (VISTA) sequence and fast field echo (FFE) sequence with 2D TSE intermediate-weighted sequence of the wrist joint at 3.0 T. Material and Methods: MRI was performed in 10 wrists of 10 healthy volunteers with isotropic 3D sequences (VISTA and FFE) and 2D TSE intermediate-weighted sequences at 3.0 T. The signal-to-noise ratio (SNR) was obtained by imaging phantom and noise-only image. Contrast ratios (CRs) were calculated between fluid and cartilage, triangular fibrocartilage complex (TFCC), and the scapholunate ligament. Two radiologists independently assessed the visibility of TFCC, carpal ligaments, cartilage, tendons and nerves with a four-point grading scale. Statistical analysis to compare CRs (one way ANOVA with a Tukey test) and grades of visibility (Kruskal-Wallis test) between three sequences and those for inter-observer agreement (kappa analysis) were performed. Results: The SNR of 2D TSE (46.26) was higher than those of VISTA (23.34) and 3D FFE (19.41). CRs were superior in 2D TSE than VISTA (P = 0.02) for fluid-cartilage and in 2D TSE than 3D FFE (P < 0.01) for fluid-TFCC. The visibility was best in 2D TSE (P < 0.01) for TFCC and in VISTA (P = 0.01) for scapholunate ligament. The visibility was better in 2D TSE and 3D FFE (P 0.04) for cartilage and in VISTA than 3D FFE (P < 0.01) for TFCC. The inter-observer agreement for the visibility of anatomic structures was moderate or substantial. Conclusion: Image quality of 2D TSE was superior to isotropic 3D MR imaging for cartilage, and TFCC. 3D FFE has better visibility for cartilage than VISTA and VISTA has superior visibility for

  14. Comparisons of Observations with Results from 3D Simulations and Implications for Predictions of Ozone Recovery

    Douglass, Anne R.; Stolarski, Richard S.; Strahan, Susan E.; Steenrod, Stephen D.; Polarsky, Brian C.


    Although chemistry and transport models (CTMs) include the same basic elements (photo- chemical mechanism and solver, photolysis scheme, meteorological fields, numerical transport scheme), they produce different results for the future recovery of stratospheric ozone as chlorofluorcarbons decrease. Three simulations will be contrasted: the Global Modeling Initiative (GMI) CTM driven by a single year\\'s winds from a general circulation model; the GMI CTM driven by a single year\\'s winds from a data assimilation system; the NASA GSFC CTM driven by a winds from a multi-year GCM simulation. CTM results for ozone and other constituents will be compared with each other and with observations from ground-based and satellite platforms to address the following: Does the simulated ozone tendency and its latitude, altitude and seasonal dependence match that derived from observations? Does the balance from analysis of observations? Does the balance among photochemical processes match that expected from observations? Can the differences in prediction for ozone recovery be anticipated from these comparisons?

  15. Comparison of parallel and spiral tagged MRI geometries in estimation of 3-D myocardial strains

    Tustison, Nicholas J.; Amini, Amir A.


    Research involving the quantification of left ventricular myocardial strain from cardiac tagged magnetic resonance imaging (MRI) is extensive. Two different imaging geometries are commonly employed by these methodologies to extract longitudinal deformation. We refer to these imaging geometries as either parallel or spiral. In the spiral configuration, four long-axis tagged image slices which intersect along the long-axis of the left ventricle are collected and in the parallel configuration, contiguous tagged long-axis images spanning the width of the left ventricle between the lateral wall and the septum are collected. Despite the number of methodologies using either or both imaging configurations, to date, no comparison has been made to determine which geometry results in more accurate estimation of strains. Using previously published work in which left ventricular myocardial strain is calculated from 4-D anatomical NURBS models, we compare the strain calculated from these two imaging geometries in both simulated tagged MR images for which ground truth strain is available as well as in in vivo data. It is shown that strains calculated using the parallel imaging protocol are more accurate than that calculated using spiral protocol.

  16. Comparison of Three-Dimensional (3D) Conformal Proton Radiotherapy (RT), 3D Conformal Photon RT, and Intensity-Modulated RT for Retroperitoneal and Intra-Abdominal Sarcomas

    Swanson, Erika L. [Department of Radiation Oncology, University of Florida, Gainesville, Florida (United States); Indelicato, Daniel J., E-mail: [Department of Radiation Oncology, University of Florida, Gainesville, Florida (United States); University of Florida Proton Therapy Institute, Jacksonville, Florida (United States); Louis, Debbie; Flampouri, Stella; Li, Zuofeng [University of Florida Proton Therapy Institute, Jacksonville, Florida (United States); Morris, Christopher G.; Paryani, Nitesh [Department of Radiation Oncology, University of Florida, Gainesville, Florida (United States); Slopsema, Roelf [University of Florida Proton Therapy Institute, Jacksonville, Florida (United States)


    Purpose: To compare three-dimensional conformal proton radiotherapy (3DCPT), intensity-modulated photon radiotherapy (IMRT), and 3D conformal photon radiotherapy (3DCRT) to predict the optimal RT technique for retroperitoneal sarcomas. Methods and Materials: 3DCRT, IMRT, and 3DCPT plans were created for treating eight patients with retroperitoneal or intra-abdominal sarcomas. The clinical target volume (CTV) included the gross tumor plus a 2-cm margin, limited by bone and intact fascial planes. For photon plans, the planning target volume (PTV) included a uniform expansion of 5 mm. For the proton plans, the PTV was nonuniform and beam-specific. The prescription dose was 50.4 Gy/Cobalt gray equivalent CGE. Plans were normalized so that >95% of the CTV received 100% of the dose. Results: The CTV was covered adequately by all techniques. The median conformity index was 0.69 for 3DCPT, 0.75 for IMRT, and 0.51 for 3DCRT. The median inhomogeneity coefficient was 0.062 for 3DCPT, 0.066 for IMRT, and 0.073 for 3DCRT. The bowel median volume receiving 15 Gy (V15) was 16.4% for 3DCPT, 52.2% for IMRT, and 66.1% for 3DCRT. The bowel median V45 was 6.3% for 3DCPT, 4.7% for IMRT, and 15.6% for 3DCRT. The median ipsilateral mean kidney dose was 22.5 CGE for 3DCPT, 34.1 Gy for IMRT, and 37.8 Gy for 3DCRT. The median contralateral mean kidney dose was 0 CGE for 3DCPT, 6.4 Gy for IMRT, and 11 Gy for 3DCRT. The median contralateral kidney V5 was 0% for 3DCPT, 49.9% for IMRT, and 99.7% for 3DCRT. Regardless of technique, the median mean liver dose was <30 Gy, and the median cord V50 was 0%. The median integral dose was 126 J for 3DCPT, 400 J for IMRT, and 432 J for 3DCRT. Conclusions: IMRT and 3DCPT result in plans that are more conformal and homogenous than 3DCRT. Based on Quantitative Analysis of Normal Tissue Effects in Clinic benchmarks, the dosimetric advantage of proton therapy may be less gastrointestinal and genitourinary toxicity.

  17. Monoligated monovalent Ni: the 3d(Ni)9 manifold of states of NiCu and comparison to the 3d9 States of AlNi, NiH, NiCl, and NiF.

    Rothschopf, Gretchen K; Morse, Michael D


    A dispersed fluorescence investigation of the low-lying electronic states of NiCu has allowed the observation of four out of the five states that derive from the 3d(Ni)9 3d(Cu)10 sigma2 manifold. Vibrational levels of the ground X2delta(5/2) state corresponding to v = 0-11 are observed and are fit to provide omega(e) = 275.93 +/- 1.06 cm(-1) and omega(e)x(e) = 1.44 +/- 0.11 cm(-1). The v = 0 levels of the higher lying states deriving from the 3d(Ni)9 3d(Cu)10 sigma2 manifold are located at 912, 1466, and 1734 cm(-1), and these states are assigned to omega values of 3/2, 1/2, and 3/2, respectively. The last of these assignments is based on selection rules and is unequivocal; the first two are based on a comparison to ab initio and ligand field calculations and could conceivably be in error. It is also possible that the v = 0 level of the state found at 912 cm(-1) is not observed, so that T0 for the lowest excited state actually lies near 658 cm(-1). These results are modeled using a matrix Hamiltonian based on the existence of a ground manifold of states deriving from the 3d9 configuration on nickel. This matrix Hamiltonian is also applied to the spectroscopically well-known molecules AlNi, NiH, NiCl, and NiF. The term energies of the 2sigma+, 2pi, and 2delta states of these molecules, which all derive from a 3d9 configuration on the nickel atom, display a clear and understandable trend as a function of the electronegativity of the ligands.

  18. The Comparison 2D and 3D Treatment Planning in Breast Cancer Radiotherapy with Emphasis on Dose Homogeneity and Lung Dose

    Zahra Falahatpour


    Full Text Available Introduction: Breast conserving radiotherapy is one of the most common procedures performed in any radiation oncology department. A tangential parallel-opposed pair is usually used for this purpose. This technique is performed using 2D or 3D treatment planning systems. The aim of this study was to compare 2D treatment planning with 3D treatment planning in tangential irradiation in breast conserving radiotherapy. In this comparison, homogeneity of isodoses in the breast volume and lung dose were considered. Material and Methods: Twenty patients with breast cancer treated with conservative surgery were included in this study. The patients were CT scanned. Two-dimensional treatment planning with the Alfard 2D TPS was performed for each patient using a single central CT slice. The data used on the Alfard 2D TPS was imported into the Eclipse 3D TPS, on which 3D treatment planning was performed. Cobalt-60 beams were used in all plans. Results: Comparing 2D and 3D treatment planning, homogeneity of isodoses was improved in 3D treatment planning (p30Gy was increased in 3D treatment planning (p< 0.01. Discussion and Conclusion: 3D treatment planning is a more suitable option for patients with breast cancer treated with conservative surgery because of improved dose homogeneity in 3D treatment planning. The results of the treatment can be improved with reduced recurrence probability and skin problems.

  19. Selection of the methods used in MR angiography with arteriovenous malformation, carotid cavernous fistula, moyamoya disease, and cerebral aneurysms; A comparison of 3-D phase-contrast MRA with 3-D time-of-flight MRA

    Ikawa, Fusao; Uozumi, Tohru; Kuwabara, Satoshi (Hiroshima Univ. (Japan). School of Medicine) (and others)


    The methods used in MR angiography (MRA) can be roughly divided into two groups: time-of-flight methods (TOF methods) which make use of the influx effect of the flow, and the phase-contrast method of Dumoulin, Souza, and their collaborators (PC method), which utilizes phase differences induced by the flow. In this study, the selection of the MRA method was determined by a comparison of the three-dimensional (3-D) PC and the 3-D TOF method in normal and clinical cases. The tool used was SIGNA Advantage (1.5T) made by GE. The 3-D PC method was applied under a pulse sequence generated by gradient-recalled acquisition in the steady state (GRASS); the pulse sequence used for the 3-D TOF method was spoiled GRASS (SPGR) in a total of 28 cases. The following conclusions were reached: the TOF method should be used when aneurysms, arteriovenous malformations (AVM), and moyamoya disease have been diagnosed, and the PC method should be used when AVM and carotid cavernous fistulae (CCF) are to be evaluated in the flow and when CCFs have been diagnosed. (author).

  20. Comparison of 3D Reconstructive Technologies Used for Morphometric Research and the Translation of Knowledge Using a Decision Matrix

    Martin, Charys M.; Roach, Victoria A.; Nguyen, Ngan; Rice, Charles L.; Wilson, Timothy D.


    The use of three-dimensional (3D) models for education, pre-operative assessment, presurgical planning, and measurement have become more prevalent. With the increase in prevalence of 3D models there has also been an increase in 3D reconstructive software programs that are used to create these models. These software programs differ in…

  1. Comparison of the Application of Web 3D Technology%Web 3D技术的应用比较



    Web 3D技术有多种,都有适用的场合,介绍了有代表性的几种Web 3D技术;Vrml、Cortona、WireFusion、EON、Virtools、Quest3D、Flash 3D和Unity 3D,比较了它们各自的特点和应用。%There are variety technology of Web 3D, and everyone has applicable occasion. Introduces several representative Web 3D technology;Such as Vrml, Cortona, WireFusion, EON, Virtools, Quest3D, Flash 3D and Unity 3D. It Compared their char⁃acteristic and application.

  2. SU-E-T-538: Lung SBRT Dosimetric Comparison of 3D Conformal and RapidArc Planning

    Jiang, R; Zhan, L; Osei, E [Grand River Hospital, Kitchener, ON (Canada)


    Purpose: Dose distributions of RapidArc Plan can be quite different from standard 3D conformal radiation therapy. SBRT plans can be optimized with high conformity or mimic the 3D conformal treatment planning with very high dose in the center of the tumor. This study quantifies the dosimetric differences among 3D conformal plan; flattened beam and FFF beam RapidArc Plans for lung SBRT. Methods: Five lung cancer patients treated with 3D non-coplanar SBRT were randomly selected. All the patients were CT scanned with 4DCT to determine the internal target volume. Abdominal compression was applied to minimize respiratory motion for SBRT patients. The prescription dose was 48 Gy in 4 fractions. The PTV coverage was optimized by two groups of objective function: one with high conformity, another mimicking 3D conformal dose distribution with high dose in the center of PTV. Optimization constraints were set to meet the criteria of the RTOG-0915 protocol. All VMAT plans were optimized with the RapidArc technique using four full arcs in Eclipse treatment planning system. The RapidArc SBRT plans with flattened 6MV beam and 6MV FFF beam were generated and dosimetric results were compared with the previous treated 3D non-coplanar plans. Results: All the RapidArc plans with flattened beam and FFF beam had similar results for the PTV and OARs. For the high conformity optimization group, The DVH of PTV exhibited a steep dose fall-off outside the PTV compared to the 3D non-coplanar plan. However, for the group mimicking the 3D conformal target dose distribution, although the PTV is very similar to the 3D conformal plan, the ITV coverage is better than 3D conformal plan. Conclusion: Due to excellent clinical experiences of 3D conformal SBRT treatment, the Rapid Arc optimization mimicking 3D conformal planning may be suggested for clinical use.

  3. Comparison of 3D conformal radiotherapy vs. intensity modulated radiation therapy (IMRT) of a stomach cancer treatment;Comparacion dosimetrica de radioterapia conformal 3D versus radioterapia de intensidad modulada (IMRT) de un tratamiento de cancer de estomago

    Bernui de V, Maria Giselle; Cardenas, Augusto; Vargas, Carlos [Hospital Nacional Carlos Alberto Seguin Escobedo (ESSALUD), Arequipa (Peru). Servicio de Radioterapia


    The purpose of this work was to compare the dosimetry in 3D Conformal Radiotherapy with Intensity Modulated Radiation Therapy (IMRT) in a treatment of stomach cancer. For this comparison we selected a patient who underwent subtotal gastrectomy and D2 dissection for a T3N3 adenocarcinoma Mx ECIIIB receiving treatment under the scheme Quimio INT 0116 - in adjuvant radiotherapy. In the treatment plan was contouring the Clinical Target Volume (CTV) and the Planning Target Volume (PTV) was generated from the expansion of 1cm of the CTV, the risky organs contouring were: the liver, kidneys and spinal cord, according to the consensus definition of volumes in gastric cancer. The 3D Conformal Radiotherapy planning is carried out using 6 half beams following the Leong Trevol technique; for the IMRT plan was used 8 fields, the delivery technique is step-and-shoot. In both cases the fields were coplanar, isocentric and the energy used was 18 MV. Intensity Modulated Radiation Therapy (IMRT), in this case has proved to be a good treatment alternative to the technique of 3D Conformal Radiotherapy; the dose distributions with IMRT have better coverage of PTV and positions of the hot spots, as well as the kidneys volume that received higher doses to 2000 cGy is lower, but the decrease in dose to the kidneys is at the expense of increased dose in other organs like the liver. (author)

  4. Comparison of 3D representations depicting micro folds: overlapping imagery vs. time-of-flight laser scanner

    Vaiopoulos, Aristidis D.; Georgopoulos, Andreas; Lozios, Stylianos G.


    A relatively new field of interest, which continuously gains grounds nowadays, is digital 3D modeling. However, the methodologies, the accuracy and the time and effort required to produce a high quality 3D model have been changing drastically the last few years. Whereas in the early days of digital 3D modeling, 3D models were only accessible to computer experts in animation, working many hours in expensive sophisticated software, today 3D modeling has become reasonably fast and convenient. On top of that, with online 3D modeling software, such as 123D Catch, nearly everyone can produce 3D models with minimum effort and at no cost. The only requirement is panoramic overlapping images, of the (still) objects the user wishes to model. This approach however, has limitations in the accuracy of the model. An objective of the study is to examine these limitations by assessing the accuracy of this 3D modeling methodology, with a Terrestrial Laser Scanner (TLS). Therefore, the scope of this study is to present and compare 3D models, produced with two different methods: 1) Traditional TLS method with the instrument ScanStation 2 by Leica and 2) Panoramic overlapping images obtained with DSLR camera and processed with 123D Catch free software. The main objective of the study is to evaluate advantages and disadvantages of the two 3D model producing methodologies. The area represented with the 3D models, features multi-scale folding in a cipollino marble formation. The most interesting part and most challenging to capture accurately, is an outcrop which includes vertically orientated micro folds. These micro folds have dimensions of a few centimeters while a relatively strong relief is evident between them (perhaps due to different material composition). The area of interest is located in Mt. Hymittos, Greece.

  5. 3D rotating wall vessel and 2D cell culture of four veterinary virus pathogens: A comparison of virus yields, portions of infectious particles and virus growth curves.

    Malenovská, Hana


    Only very few comparative studies have been performed that evaluate general trends of virus growth under 3D in comparison with 2D cell culture conditions. The aim of this study was to investigate differences when four animal viruses are cultured in 2D and 3D. Suid herpesvirus 1 (SuHV-1), Vesicular stomatitis virus (VSIV), Bovine adenovirus (BAdV) and Bovine parainfluenza 3 virus (BPIV-3) were cultivated in 3D rotating wall vessels (RWVs) and conventional 2D cultures. The production of virus particles, the portion of infectious particles, and the infectious growth curves were compared. For all viruses, the production of virus particles (related to cell density), including the non-infectious ones, was lower in 3D than in 2D culture. The production of only infectious particles was significantly lower in BAdV and BPIV-3 in 3D cultures in relation to cell density. The two cultivation approaches resulted in significantly different virus particle-to-TCID50 ratios in three of the four viruses: lower in SuHV-1 and BPIV-3 and higher in BAdV in 3D culture. The infectious virus growth rates were not significantly different in all viruses. Although 3D RWV culture resulted in lower production of virus particles compared to 2D systems, the portion of infectious particles was higher for some viruses.

  6. A 3-D Contextual Classifier

    Larsen, Rasmus


    . This includes the specification of a Gaussian distribution for the pixel values as well as a prior distribution for the configuration of class variables within the cross that is m ade of a pixel and its four nearest neighbours. We will extend this algorithm to 3-D, i.e. we will specify a simultaneous Gaussian...... distr ibution for a pixel and its 6 nearest 3-D neighbours, and generalise the class variable configuration distribution within the 3-D cross. The algorithm is tested on a synthetic 3-D multivariate dataset....

  7. Comparison of Radiative Energy Flows in Observational Datasets and Climate Modeling

    Raschke, Ehrhard; Kinne, Stefan; Rossow, William B.; Stackhouse, Paul W. Jr.; Wild, Martin


    This study examines radiative flux distributions and local spread of values from three major observational datasets (CERES, ISCCP, and SRB) and compares them with results from climate modeling (CMIP3). Examinations of the spread and differences also differentiate among contributions from cloudy and clear-sky conditions. The spread among observational datasets is in large part caused by noncloud ancillary data. Average differences of at least 10Wm(exp -2) each for clear-sky downward solar, upward solar, and upward infrared fluxes at the surface demonstrate via spatial difference patterns major differences in assumptions for atmospheric aerosol, solar surface albedo and surface temperature, and/or emittance in observational datasets. At the top of the atmosphere (TOA), observational datasets are less influenced by the ancillary data errors than at the surface. Comparisons of spatial radiative flux distributions at the TOA between observations and climate modeling indicate large deficiencies in the strength and distribution of model-simulated cloud radiative effects. Differences are largest for lower-altitude clouds over low-latitude oceans. Global modeling simulates stronger cloud radiative effects (CRE) by +30Wmexp -2) over trade wind cumulus regions, yet smaller CRE by about -30Wm(exp -2) over (smaller in area) stratocumulus regions. At the surface, climate modeling simulates on average about 15Wm(exp -2) smaller radiative net flux imbalances, as if climate modeling underestimates latent heat release (and precipitation). Relative to observational datasets, simulated surface net fluxes are particularly lower over oceanic trade wind regions (where global modeling tends to overestimate the radiative impact of clouds). Still, with the uncertainty in noncloud ancillary data, observational data do not establish a reliable reference.

  8. Comparison of different coupling CFD–STH approaches for pre-test analysis of a TALL-3D experiment

    Papukchiev, Angel, E-mail: [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, Garching n. Munich (Germany); Jeltsov, Marti; Kööp, Kaspar; Kudinov, Pavel [KTH Royal Institute of Technology, Stockholm (Sweden); Lerchl, Georg [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, Garching n. Munich (Germany)


    Highlights: • Thermal-hydraulic system codes and CFD tools are coupled. • Pre-test calculations for the TALL-3D facility are performed. • Complex flow and heat transfer phenomena are modeled. • Comparative analyses have been performed. - Abstract: The system thermal-hydraulic (STH) code ATHLET was coupled with the commercial 3D computational fluid dynamics (CFD) software package ANSYS CFX to improve ATHLET simulation capabilities for flows with pronounced 3D phenomena such as flow mixing and thermal stratification. Within the FP7 European project THINS (Thermal Hydraulics of Innovative Nuclear Systems), validation activities for coupled thermal-hydraulic codes are being carried out. The TALL-3D experimental facility, operated by KTH Royal Institute of Technology in Stockholm, is designed for thermal-hydraulic experiments with lead-bismuth eutectic (LBE) coolant at natural and forced circulation conditions. GRS carried out pre-test simulations with ATHLET–ANSYS CFX for the TALL-3D experiment T01, while KTH scientists perform these analyses with the coupled code RELAP5/STAR CCM+. In the experiment T01 the main circulation pump is stopped, which leads to interesting thermal-hydraulic transient with local 3D phenomena. In this paper, the TALL-3D behavior during T01 is analyzed and the results of the coupled pre-test calculations, performed by GRS (ATHLET–ANSYS CFX) and KTH (RELAP5/STAR CCM+) are directly compared.

  9. 三种人体数据集的腓骨瓣三维可视化应用研究%Application of 3D visnalization models of fibular flap developed by three human digital datasets

    豆勇刚; 余斌; 钟梅; 金丹; 黎健伟; 张元智; 裴国献


    目的 研究三种人体数据集的腓骨瓣三维可视化应用. 方法 ①健康自愿者2人,经肘静脉注射造影剂,使用64排多层螺旋CT进行双下肢扫描,观察腓动脉及其分支分布及彼此间的吻合情况,将下肢二维灰度.DICOM格式图像以三维体数据的形式输入计算机,应用Amira4.1软件对腓动脉及腓骨的结构进行三维重建并立体显示.②取新鲜捐献尸体1具,采用改良的明胶-氧化铅灌注术经腹主动脉灌注,灌注后对双下肢行连续螺旋CT扫描,观察腓动脉及其分支的分布情况.利用Amira4.1软件对腓动脉及其分支结构进行三维重建并立体显示.③应用"虚拟中国人"(VCH)男性3号数据集,在薄层断面图像上观察小腿主要解剖结构,应用Amira4.1软件对小腿主要结构进行计算机三维重建并立体显示. 结果 运用Amira4.1图像处理软件,在三维表面重建的图像中可清晰地观察到外科腓骨瓣各解剖结构的形态,特别是腓动脉的分支情况和体表的投影得到很好的显示.利用软件的Movie Maker模板创建电影文件,将其制作为电影,画面清晰流畅,可直观、立体地显示形态特征. 结论 三种数据集重建的图像可以提供正常腓骨瓣三维动态解剖,对腓骨瓣的临床试验、基础研究、临床训练和手术规划具有重要应用价值.%Objective To explore application of the 3D visualization models of fibular flap developed by 3 human digital datasets. Methods First, 2 adult volunteers underwent contrast-enhance CT angiography of lower limbs using a 64-row multi-slice spiral CT after injection of Ultravist (3.5ml/s) through the median cubital vein. The 2D images from the scanning in DICOM format were transformed into three-dimensional data by computer. The structures of fibular flap were observed and digital visualization models of fibular flap were established by three-dimensional computerixed reconstruction out of these data using Amira 4. 1

  10. 3D Simulations of Plasma Filaments in the Scrape Off Layer: A Comparison with Models of Reduced Dimensionality

    Easy, Luke; Omotani, John; Dudson, Benjamin; Havlíčková, Eva; Tamain, Patrick; Naulin, Volker; Nielsen, Anders H


    This paper presents simulations of isolated 3D filaments in a slab geometry obtained using a 3D reduced fluid code. First, systematic scans were performed to investigate how the dynamics of a filament are affected by its amplitude, perpendicular size and parallel extent. The perpendicular size of the filament was found to have a strong influence on its motions, as it determined the relative importance of parallel currents to polarisation and viscous currents, whilst drift-wave instabilities were observed if the initial amplitude of the blob was increased sufficiently. Next, the 3D simulations were compared to 2D simulations using different parallel closures; namely, the sheath dissipation closure, which neglects parallel gradients, and the vorticity advection closure, which neglects the influence of parallel currents. The vorticity advection closure was found to not replicate the 3D perpendicular dynamics and overestimated the initial radial acceleration of all the filaments studied. In contrast, a more satis...

  11. Comparison of simulated and experimental 3D laser images using a GmAPD array: application to long range detection

    Coyac, Antoine; Riviere, Nicolas; Hespel, Laurent; Briottet, Xavier


    In this paper, we show the feasibility and the benefit to use a Geiger-mode Avalanche Photo-Diode (GmAPD) array for long range detection, up to several kilometers. A simulation of a Geiger detection sensor is described, which is a part of our end-to-end laser simulator, to generate simulated 3D laser images from synthetic scenes. Resulting 3D point clouds have been compared to experimental acquisitions, performed with our GmAPD 3D camera on similar scenarios. An operational case of long range detection is presented: a copper cable outstretched above the ground, 1 kilometer away the experimental system and with a horizontal line-of-sight (LOS). The detection of such a small object from long distance observation strongly suggests that GmAPD focal plane arrays could be easily used for real-time 3D mapping or surveillance applications from airborne platforms, with good spatial and temporal resolutions.

  12. Comparison between 3D-CTA with volume reconstruction and 3D-DSA in diagnosis of acute rupture of minute cerebral aneurysms%容积重建成像3D-CTA与3D-DSA在诊断急性破裂性颅内微小动脉瘤的研究

    曾少建; 舒航; 陈光忠; 李昭杰; 詹升全; 林晓风; 周东


    Objective To evaluate the diagnostic value of three dimensional computed tomographic angiog-raphy (3D-CTA) with volume reconstruction (VR) and 3D digital subtraction angiography (3D-DSA) in diagnosis of minimal cerebral aneurysms. Method A total of 174 patients in Guangdong General Hospital, May 2007 to November 2008, of subarachnoid hemorrhage were checked upon the original imaging obtained by GE' s Light Speed Plus 64 volume spiral CT scanner at first, and then by the means of using Volume rendering (VR) three dimen-sional reconstruction and assisting the use of multiple planar reconstruction (MPR) to complete the 3D-DSA imag-ing at last. The volume rendering (VR) was assessed. Results Eleven very small cerebral aneurysms in 174 pa-tients with subarachnoid hemorrhage were diagnosed by CTA and 10 of them by 3D-DSA. Finally, all of 11 patients were confirmed by intracranial operations. The 3D-CTA (VR) clearly showed the shape and size of the intracranial aneurysms and their relationship to adjacent structures as well. There was no significant difference in the diagnosis of very small cerebral aneurysms between 3D-DSA and 3D-CTA(VR). Conclusions The 3D-CTA (VR) is a re-liable and rapid non-invasive diagnostic device for very small intracranial aneurysms. For the emergency operation,3D-CTA (VR) can provide more detailed imaging information to help the development of treatment strategy.%目的 对比研究容积重建成像三维CT血管造影与三维DSA(3D-DSA)在颅内微小动脉瘤诊疗中的临床应用价值.方法 对广东省人民医院2007年5月至2008年11月收治的174例蛛网膜下腔出血患者首先采用采用GE公司的Light Speed Plus 64排容积螺旋CT机获得原始图像,采用容积重建成像技术(VR)进行三维重建.并辅助运用多轴面重建(MPR),然后再行全脑血管造影术,并行3D-DSA成像.结果 本组174例蛛网膜下腔出血患者诊断为颅内微小动脉瘤11例,均经开颅手术证实;其中CTA诊断11例,3D

  13. Comparison between 3D dynamics filter technique, field-in-field, electronic compensator in breast cancer; Comparacao entre tecnica 3D com filtro dinamico, field-in-field e compensacao eletronica para cancer de mama

    Trindade, Cassia; Silva, Leonardo P.; Martins, Lais P.; Garcia, Paulo L.; Santos, Maira R.; Bastista, Delano V.S.; Vieira, Anna Myrian M.T.L.; Rocha, Igor M., E-mail: [Instituto Nacional de Cancer (INCA), Rio de Janeiro, RJ (Brazil)


    The radiotherapy has been used in a wild scale in breast cancer treatment. With this high demand, new technologies have been developed to improve the dose distribution in the target while reducing the dose delivered in critical organs. In this study, performed with one clinical case, three planning were done for comparison: 3D technique with dynamic filter, 3D with field-in-field technique (forward-planned IMRT) and 3D technique using electronic compensator (ECOMP). The planning were done with a 6MV photon beam using the Eclipse software, version 8.6 (Varian Medical Systems). The PTV was drawn covering the whole breast and the critical organs were: the lung on the irradiated side, the heart, the contralateral breast and the anterior descending coronary artery (LAD). The planning using the compensator technique permitted more homogeneous dose distribution in the target volume. The V20 value of the lung on the irradiated side was 8,3% for the electronic compensator technique, 8,9% for the field-in-field technique and 8,2% for the dynamic filter technique. For the heart the dose range was 15.7 - 139.9 cGy, 16.3 - 148.4 cGy for the dynamic filter technique and 19.6 - 157.0 cGy for the field-in-field technique. The dose gradient was 11% with compensator electronic, 15% dynamic filter technique and 13% with field-in-field. The application of electronic technique in breast cancer treatment allows better dose distribution while reduces dose in critical organs, but in the same time requires a quality assurance. (author)

  14. 3D-MR myelography (3D-MRM) for the diagnosis of lumbal nerve root compression syndrome. A comparison with conventional myelography. 3D-MR Myelographie (3D-MRM) zur Diagnose von lumbalen Nervenwurzelkompressionssyndromen. Vergleichsstudie zu konventioneller Myelographie

    Eberhardt, K.E.W. (Neuroradiologische Abt., Neurochirurgische Klinik, Nuernberg-Erlangen Univ., Erlangen (Germany)); Hollenbach, H.P.; Huk, W.J.


    65 patients with nerve root compression syndrome were examined using a new type of MR-technique, which is comparable to the conventional X-ray myelography. The results of the prospective case study were compared with previous clinical experiences (1). For the examinations a 1.0 T whole body MR-system (Siemens Magnetom Impact) was used. A strong T[sub 2]*-weighted 3D-FISP sequence (TR=73 ms, TE=21 ms, [alpha]=7 ) was applied in sagittal orientation using a circularly polarized oval spine coil. To obtain fat suppression a frequency selective 1-3-3-1 prepulse was applied prior to the imaging sequence. The acquired 3D-data set was evaluated using a Maximum Intensity Projection (MIP) program. Our results confirmed earlier experiences which showed that the diagnostic sensitivity of 3D-MR myelography (3D-MRM) is comparable to that of conventional X-ray myelography. In cases of severe spinal canal stenosis and spondylolisthesis, and in cases of postoperative scar tissue with nerve root compressions, the sensitivity of the 3D-MRM is higher as compared to that of conventional X-ray myelography. (orig.)

  15. A dosimetric comparison of 3D conformal vs intensity modulated vs volumetric arc radiation therapy for muscle invasive bladder cancer

    Foroudi Farshad


    Full Text Available Abstract Background To compare 3 Dimensional Conformal radiotherapy (3D-CRT with Intensity Modulated Radiotherapy (IMRT with Volumetric-Modulated Arc Therapy (VMAT for bladder cancer. Methods Radiotherapy plans for 15 patients with T2-T4N0M0 bladder cancer were prospectively developed for 3-DCRT, IMRT and VMAT using Varian Eclipse planning system. The same radiation therapist carried out all planning and the same clinical dosimetric constraints were used. 10 of the patients with well localised tumours had a simultaneous infield boost (SIB of the primary tumour planned for both IMRT and VMAT. Tumour control probabilities and normal tissue complication probabilities were calculated. Results Mean planning time for 3D-CRT, IMRT and VMAT was 30.0, 49.3, and 141.0 minutes respectively. The mean PTV conformity (CI index for 3D-CRT was 1.32, for IMRT 1.05, and for VMAT 1.05. The PTV Homogeneity (HI index was 0.080 for 3D-CRT, 0.073 for IMRT and 0.086 for VMAT. Tumour control and normal tissue complication probabilities were similar for 3D-CRT, IMRT and VMAT. The mean monitor units were 267 (range 250–293 for 3D-CRT; 824 (range 641–1083 for IMRT; and 403 (range 333–489 for VMAT (P  Conclusions VMAT is associated with similar dosimetric advantages as IMRT over 3D-CRT for muscle invasive bladder cancer. VMAT is associated with faster delivery times and less number of mean monitor units than IMRT. SIB is feasible in selected patients with localized tumours.

  16. Comparison of 3D reconstruction of mandible for pre-operative planning using commercial and open-source software

    Abdullah, Johari Yap; Omar, Marzuki; Pritam, Helmi Mohd Hadi; Husein, Adam; Rajion, Zainul Ahmad


    3D printing of mandible is important for pre-operative planning, diagnostic purposes, as well as for education and training. Currently, the processing of CT data is routinely performed with commercial software which increases the cost of operation and patient management for a small clinical setting. Usage of open-source software as an alternative to commercial software for 3D reconstruction of the mandible from CT data is scarce. The aim of this study is to compare two methods of 3D reconstruction of the mandible using commercial Materialise Mimics software and open-source Medical Imaging Interaction Toolkit (MITK) software. Head CT images with a slice thickness of 1 mm and a matrix of 512x512 pixels each were retrieved from the server located at the Radiology Department of Hospital Universiti Sains Malaysia. The CT data were analysed and the 3D models of mandible were reconstructed using both commercial Materialise Mimics and open-source MITK software. Both virtual 3D models were saved in STL format and exported to 3matic and MeshLab software for morphometric and image analyses. Both models were compared using Wilcoxon Signed Rank Test and Hausdorff Distance. No significant differences were obtained between the 3D models of the mandible produced using Mimics and MITK software. The 3D model of the mandible produced using MITK open-source software is comparable to the commercial MIMICS software. Therefore, open-source software could be used in clinical setting for pre-operative planning to minimise the operational cost.

  17. Comparison of 3D point clouds produced by LIDAR and UAV photoscan in the Rochefort cave (Belgium)

    Watlet, Arnaud; Triantafyllou, Antoine; Kaufmann, Olivier; Le Mouelic, Stéphane


    Amongst today's techniques that are able to produce 3D point clouds, LIDAR and UAV (Unmanned Aerial Vehicle) photogrammetry are probably the most commonly used. Both methods have their own advantages and limitations. LIDAR scans create high resolution and high precision 3D point clouds, but such methods are generally costly, especially for sporadic surveys. Compared to LIDAR, UAV (e.g. drones) are cheap and flexible to use in different kind of environments. Moreover, the photogrammetric processing workflow of digital images taken with UAV becomes easier with the rise of many affordable software packages (e.g. Agisoft, PhotoModeler3D, VisualSFM). We present here a challenging study made at the Rochefort Cave Laboratory (South Belgium) comprising surface and underground surveys. The site is located in the Belgian Variscan fold-and-thrust belt, a region that shows many karstic networks within Devonian limestone units. A LIDAR scan has been acquired in the main chamber of the cave (~ 15000 m³) to spatialize 3D point cloud of its inner walls and infer geological beds and structures. Even if the use of LIDAR instrument was not really comfortable in such caving environment, the collected data showed a remarkable precision according to few control points geometry. We also decided to perform another challenging survey of the same cave chamber by modelling a 3D point cloud using photogrammetry of a set of DSLR camera pictures taken from the ground and UAV pictures. The aim was to compare both techniques in terms of (i) implementation of data acquisition and processing, (ii) quality of resulting 3D points clouds (points density, field vs cloud recovery and points precision), (iii) their application for geological purposes. Through Rochefort case study, main conclusions are that LIDAR technique provides higher density point clouds with slightly higher precision than photogrammetry method. However, 3D data modeled by photogrammetry provide visible light spectral information


    D. Han; S.R. Qiao; M. Li; J.T. Hou; X.J. Wu


    The differences of tension-tension fatigue and tensile creep characters of 2D-C/SiCand 3D-C/SiC composites have been scrutinized to meet the engineering needs. Experiments of tension-tension fatigue and tensile creep are carried out under vacuum high temperature condition. All of the high temperature fatigue curves are flat; the fatigue curves of the 2D-C/SiC are flatter and even parallel to the horizontal axis. While the tension-tension fatigue limit of the 3D-C/SiC is higher than that of the 2D-C/SiC, the fiber pullout length of the fatigue fracture surface of the 3D-C/SiC is longer than that of the 2D-C/SiC, and fracture morphology of the 3D-C/SiC is rougher, and pullout length of the fiber tows is longer. At the same time the 3D-C/SiC has higher tensile creep resistance. The tensile curve and the tensile creep curve of both materials consist of a series of flat step. These phenomena can be explained by the non-continuity of the damage.

  19. Comparison of 3D and 4D Monte Carlo optimization in robotic tracking stereotactic body radiotherapy of lung cancer

    Chan, Mark K.H. [Tuen Mun Hospital, Department of Clinical Oncology, Hong Kong (S.A.R) (China); Werner, Rene [The University Medical Center Hamburg-Eppendorf, Department of Computational Neuroscience, Hamburg (Germany); Ayadi, Miriam [Leon Berard Cancer Center, Department of Radiation Oncology, Lyon (France); Blanck, Oliver [University Clinic of Schleswig-Holstein, Department of Radiation Oncology, Luebeck (Germany); CyberKnife Center Northern Germany, Guestrow (Germany)


    To investigate the adequacy of three-dimensional (3D) Monte Carlo (MC) optimization (3DMCO) and the potential of four-dimensional (4D) dose renormalization (4DMC{sub renorm}) and optimization (4DMCO) for CyberKnife (Accuray Inc., Sunnyvale, CA) radiotherapy planning in lung cancer. For 20 lung tumors, 3DMCO and 4DMCO plans were generated with planning target volume (PTV{sub 5} {sub mm}) = gross tumor volume (GTV) plus 5 mm, assuming 3 mm for tracking errors (PTV{sub 3} {sub mm}) and 2 mm for residual organ deformations. Three fractions of 60 Gy were prescribed to ≥ 95 % of the PTV{sub 5} {sub mm}. Each 3DMCO plan was recalculated by 4D MC dose calculation (4DMC{sub recal}) to assess the dosimetric impact of organ deformations. The 4DMC{sub recal} plans were renormalized (4DMC{sub renorm}) to 95 % dose coverage of the PTV{sub 5} {sub mm} for comparisons with the 4DMCO plans. A 3DMCO plan was considered adequate if the 4DMC{sub recal} plan showed ≥ 95 % of the PTV{sub 3} {sub mm} receiving 60 Gy and doses to other organs at risk (OARs) were below the limits. In seven lesions, 3DMCO was inadequate, providing < 95 % dose coverage to the PTV{sub 3} {sub mm}. Comparison of 4DMC{sub recal} and 3DMCO plans showed that organ deformations resulted in lower OAR doses. Renormalizing the 4DMC{sub recal} plans could produce OAR doses higher than the tolerances in some 4DMC{sub renorm} plans. Dose conformity of the 4DMC{sub renorm} plans was inferior to that of the 3DMCO and 4DMCO plans. The 4DMCO plans did not always achieve OAR dose reductions compared to 3DMCO and 4DMC{sub renorm} plans. This study indicates that 3DMCO with 2 mm margins for organ deformations may be inadequate for Cyberknife-based lung stereotactic body radiotherapy (SBRT). Renormalizing the 4DMC{sub recal} plans could produce degraded dose conformity and increased OAR doses; 4DMCO can resolve this problem. (orig.) [German] Untersucht wurde die Angemessenheit einer dreidimensionalen (3-D) Monte

  20. RELAP5-3D Developmental Assessment: Comparison of Version 4.2.1i on Linux and Windows

    Paul D. Bayless


    Figures have been generated comparing the parameters used in the developmental assessment of the RELAP5-3D code, version 4.2i, compiled on Linux and Windows platforms. The figures, which are the same as those used in Volume III of the RELAP5-3D code manual, compare calculations using the semi-implicit solution scheme with available experiment data. These figures provide a quick, visual indication of how the code predictions differ between the Linux and Windows versions.

  1. Description of premixing with the MC3D code including molten jet behavior modeling. Comparison with FARO experimental results

    Berthoud, G.; Crecy, F. de; Meignen, R.; Valette, M. [CEA-G, DRN/DTP/SMTH, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France)


    The premixing phase of a molten fuel-coolant interaction is studied by the way of mechanistic multidimensional calculation. Beside water and steam, corium droplet flow and continuous corium jet flow are calculated independent. The 4-field MC3D code and a detailed hot jet fragmentation model are presented. MC3D calculations are compared to the FARO L14 experiment results and are found to give satisfactory results; heat transfer and jet fragmentation models are still to be improved to predict better final debris size values. (author)

  2. RELAP5-3D Developmental Assessment. Comparison of Version 4.3.4i on Linux and Windows

    Bayless, Paul David [Idaho National Lab. (INL), Idaho Falls, ID (United States)


    Figures have been generated comparing the parameters used in the developmental assessment of the RELAP5-3D code, version 4.3i, compiled on Linux and Windows platforms. The figures, which are the same as those used in Volume III of the RELAP5-3D code manual, compare calculations using the semi-implicit solution scheme with available experiment data. These figures provide a quick, visual indication of how the code predictions differ between the Linux and Windows versions.

  3. RELAP5-3D developmental assessment: Comparison of version 4.2.1i on Linux and Windows

    Bayless, Paul D. [Idaho National Lab. (INL), Idaho Falls, ID (United States)


    Figures have been generated comparing the parameters used in the developmental assessment of the RELAP5-3D code, version 4.2i, compiled on Linux and Windows platforms. The figures, which are the same as those used in Volume III of the RELAP5-3D code manual, compare calculations using the semi-implicit solution scheme with available experiment data. These figures provide a quick, visual indication of how the code predictions differ between the Linux and Windows versions.

  4. Comparison of dosimetric parameters and toxicity in esophageal cancer patients undergoing 3D conformal radiotherapy or VMAT

    Muench, Stefan; Aichmeier, Sylvia; Duma, Marciana-Nona; Oechsner, Markus; Habermehl, Daniel [TU Muenchen, Department of Radiation Oncology, Klinikum rechts der Isar, Muenchen (Germany); Hapfelmeier, Alexander [TU Muenchen, Institute of Medical Statistics and Epidemiology (IMSE), Klinikum rechts der Isar, Muenchen (Germany); Feith, Marcus [TU Muenchen, Department of Visceral Surgery, Klinikum rechts der Isar, Muenchen (Germany); Combs, Stephanie E. [TU Muenchen, Department of Radiation Oncology, Klinikum rechts der Isar, Muenchen (Germany); Helmholtz Zentrum Muenchen, Institute of Innovative Radiotherapy (iRT), Oberschleissheim (Germany)


    Volumetric-modulated arc therapy (VMAT) achieves high conformity to the planned target volume (PTV) and good sparing of organs at risk (OAR). This study compares dosimetric parameters and toxicity in esophageal cancer (EC) patients treated with VMAT and 3D conformal radiotherapy (3D-CRT). Between 2007 and 2014, 17 SC patients received neoadjuvant chemoradiation (CRT) with VMAT. Dose-volume histograms and toxicity were compared between these patients and 20 treated with 3D-CRT. All patients were irradiated with a total dose of 45 Gy. All VMAT patients received simultaneous chemotherapy with cisplatin and 5-fluorouracil (5-FU) in treatment weeks 1 and 5. Of 20 patients treated with 3D-CRT, 13 (65 %) also received CRT with cisplatin and 5-FU, whereas 6 patients (30 %) received CRT with weekly oxaliplatin and cetuximab, and a continuous infusion of 5-FU (OE-7). There were no differences in baseline characteristics between the treatment groups. For the lungs, VMAT was associated with a higher V{sub 5} (median 90.1 % vs. 79.7 %; p = 0.013) and V{sub 10} (68.2 % vs. 56.6 %; p = 0.014), but with a lower V{sub 30} (median 6.6 % vs. 11.0 %; p = 0.030). Regarding heart parameters, VMAT was associated with a higher V{sub 5} (median 100.0 % vs. 91.0 %; p = 0.043), V{sub 10} (92.0 % vs. 79.2 %; p = 0.047), and D{sub max} (47.5 Gy vs. 46.3 Gy; p = 0.003), but with a lower median dose (18.7 Gy vs. 30.0 Gy; p = 0.026) and V{sub 30} (17.7 % vs. 50.4 %; p = 0.015). Complete resection was achieved in 16 VMAT and 19 3D-CRT patients. Due to systemic progression, 2 patients did not undergo surgery. The most frequent postoperative complication was anastomosis insufficiency, occurring in 1 VMAT (6.7 %) and 5 3D-CRT patients (27.8 %; p = 0.180). Postoperative pneumonia was seen in 2 patients of each group (p = 1.000). There was no significant difference in 3-year overall (65 % VMAT vs. 45 % 3D-CRT; p = 0.493) or 3-year progression-free survival (53 % VMAT vs. 35 % 3D-CRT; p = 0

  5. Segmentation of Textures Defined on Flat vs. Layered Surfaces using Neural Networks: Comparison of 2D vs. 3D Representations.

    Oh, Sejong; Choe, Yoonsuck


    Texture boundary detection (or segmentation) is an important capability in human vision. Usually, texture segmentation is viewed as a 2D problem, as the definition of the problem itself assumes a 2D substrate. However, an interesting hypothesis emerges when we ask a question regarding the nature of textures: What are textures, and why did the ability to discriminate texture evolve or develop? A possible answer to this question is that textures naturally define physically distinct (i.e., occluded) surfaces. Hence, we can hypothesize that 2D texture segmentation may be an outgrowth of the ability to discriminate surfaces in 3D. In this paper, we conducted computational experiments with artificial neural networks to investigate the relative difficulty of learning to segment textures defined on flat 2D surfaces vs. those in 3D configurations where the boundaries are defined by occluding surfaces and their change over time due to the observer's motion. It turns out that learning is faster and more accurate in 3D, very much in line with our expectation. Furthermore, our results showed that the neural network's learned ability to segment texture in 3D transfers well into 2D texture segmentation, bolstering our initial hypothesis, and providing insights on the possible developmental origin of 2D texture segmentation function in human vision.

  6. Comparison Between 2-D and 3-D Stiffness Matrix Model Simulation of Sasw Inversion for Pavement Structure

    Sri Atmaja P. Rosidi


    Full Text Available The Spectral Analysis of Surface Wave (SASW method is a non-destructive in situ seismic technique used to assess and evaluate the material stiffness (dynamic elastic modulus and thickness of pavement layers at low strains. These values can be used analytically to calculate load capacities in order to predict the performance of pavement system. The SASW method is based on the dispersion phenomena of Rayleigh waves in layered media. In order to get the actual shear wave velocities, 2-D and 3-D models are used in the simulation of the inversion process for best fitting between theoretical and empirical dispersion curves. The objective of this study is to simulate and compare the 2-D and 3-D model of SASW analysis in the construction of the theoretical dispersion curve for pavement structure evaluation. The result showed that the dispersion curve from the 3-D model was similar with the dispersion curve of the actual pavement profile compared to the 2-D model. The wave velocity profiles also showed that the 3-D model used in the SASW analysis is able to detect all the distinct layers of flexible pavement units.

  7. A Comparison of Methods for Decoupling Tongue and Lower Lip from Jaw Movements in 3D Articulography

    Henriques, Rafael Neto; van Lieshout, Pascal


    Purpose: One popular method to study the motion of oral articulators is 3D electromagnetic articulography. For many studies, it is important to use an algorithm to decouple the motion of the tongue and the lower lip from the motion of the mandible. In this article, the authors describe and compare 4 methods for decoupling jaw motion by using 3D…

  8. Cytotoxic responses of carnosic acid and doxorubicin on breast cancer cells in butterfly-shaped microchips in comparison to 2D and 3D culture.

    Yildiz-Ozturk, Ece; Gulce-Iz, Sultan; Anil, Muge; Yesil-Celiktas, Ozlem


    Two dimensional (2D) cell culture systems lack the ability to mimic in vivo conditions resulting in limitations for preclinical cell-based drug and toxicity screening assays and modelling tumor biology. Alternatively, 3D cell culture systems mimic the specificity of native tissue with better physiological integrity. In this regard, microfluidic chips have gained wide applicability for in vitro 3D cancer cell studies. The aim of this research was to develop a 3D biomimetic model comprising culture of breast cancer cells in butterfly-shaped microchip to determine the cytotoxicity of carnosic acid and doxorubicin on both estrogen dependent (MCF-7) and independent (MDA-MB231) breast cancer cells along with healthy mammary epithelial cells (MCF-10A) in 2D, 3D Matrigel™ and butterfly-shaped microchip environment. According to the developed mimetic model, carnosic acid exhibited a higher cytotoxicity towards MDA-MB 231, while doxorubicin was more effective against MCF-7. Although the cell viabilities were higher in comparison to 2D and 3D cell culture systems, the responses of the investigated molecules were different in the microchips based on the molecular weight and structural complexity indicating the importance of biomimicry in a physiologically relevant matrix.

  9. Investigation of the quantitative accuracy of 3D iterative reconstruction algorithms in comparison to filtered back projection method: a phantom study

    Abuhadi, Nouf; Bradley, David; Katarey, Dev; Podolyak, Zsolt; Sassi, Salem


    Introduction: Single-Photon Emission Computed Tomography (SPECT) is used to measure and quantify radiopharmaceutical distribution within the body. The accuracy of quantification depends on acquisition parameters and reconstruction algorithms. Until recently, most SPECT images were constructed using Filtered Back Projection techniques with no attenuation or scatter corrections. The introduction of 3-D Iterative Reconstruction algorithms with the availability of both computed tomography (CT)-based attenuation correction and scatter correction may provide for more accurate measurement of radiotracer bio-distribution. The effect of attenuation and scatter corrections on accuracy of SPECT measurements is well researched. It has been suggested that the combination of CT-based attenuation correction and scatter correction can allow for more accurate quantification of radiopharmaceutical distribution in SPECT studies (Bushberg et al., 2012). However, The effect of respiratory induced cardiac motion on SPECT images acquired using higher resolution algorithms such 3-D iterative reconstruction with attenuation and scatter corrections has not been investigated. Aims: To investigate the quantitative accuracy of 3D iterative reconstruction algorithms in comparison to filtered back projection (FBP) methods implemented on cardiac SPECT/CT imaging with and without CT-attenuation and scatter corrections. Also to investigate the effects of respiratory induced cardiac motion on myocardium perfusion quantification. Lastly, to present a comparison of spatial resolution for FBP and ordered subset expectation maximization (OSEM) Flash 3D together with and without respiratory induced motion, and with and without attenuation and scatter correction. Methods: This study was performed on a Siemens Symbia T16 SPECT/CT system using clinical acquisition protocols. Respiratory induced cardiac motion was simulated by imaging a cardiac phantom insert whilst moving it using a respiratory motion motor

  10. A fractal approach to the dark silicon problem: a comparison of 3D computer architectures -- standard slices versus fractal Menger sponge geometry

    Herrmann, Richard


    The dark silicon problem, which limits the power-growth of future computer generations, is interpreted as a heat energy transport problem when increasing the energy emitting surface area within a given volume. A comparison of two 3D-configuration models, namely a standard slicing and a fractal surface generation within the Menger sponge geometry is presented. It is shown, that for iteration orders $n>3$ the fractal model shows increasingly better thermal behavior. As a consequence cooling pro...

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

    Nave, Maryana I.; Kornev, Konstantin G.


    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.

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

    Nave, Maryana I.; Kornev, Konstantin G.


    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.

  13. Comparison of the global air-sea freshwater exchange evaluated from independent datasets

    ZHOU Tianjun


    The implied air-sea freshwater flux is examined in two reanalysis datasets provided respectively by European Center for Medium-range Weather Forecasts and National Center for Environmental Prediction. Not only for annual mean state but also for seasonal variation, two reanalyses agree qualitatively well with each other, and both can reproduce reasonably the global distribution of E-P (i.e. Evaporation minus Precipitation). In the view of quantitative comparison, however, remarkable difference has been found on regional scales, especially over the middle and lower latitudes, with some local disagreement exceeding 100 cm/yr. One important difference between current and previous evaluation is the new found net evaporation over the high latitude North Atlantic, which is demonstrated to result from the transient disturbances during boreal winter.

  14. Craniofacial vertical bone augmentation: a comparison between 3D printed monolithic monetite blocks and autologous onlay grafts in the rabbit


    Onlay autografting is amongst the most predictable techniques for craniofacial vertical bone augmentation, however, complications related to donor site surgery are common and synthetic alternatives to onlay autografts are desirable. Recent studies have shownthat the acidic calcium phosphates, brushite and monetite, are osteoconductive, osteoinductive and resorb faster in vivo that hydroxyapatite.Moreover, they can be 3D printed allowing precise host bone-implant specific conformation. the obj...

  15. Dosimetric comparison of preoperative single-fraction partial breast radiotherapy techniques: 3D CRT, noncoplanar IMRT, coplanar IMRT, and VMAT.

    Yoo, Sua; Blitzblau, Rachel; Yin, Fang-Fang; Horton, Janet K


    The purpose of this study was to compare dosimetric parameters of treatment plans among four techniques for preoperative single-fraction partial breast radiotherapy in order to select an optimal treatment technique. The techniques evaluated were noncoplanar 3D conformal radiation therapy (3D CRT), noncoplanar intensity-modulated radiation therapy (IMRTNC), coplanar IMRT (IMRTCO), and volumetric-modulated arc therapy (VMAT). The planning CT scans of 16 patients in the prone position were used in this study, with the single-fraction prescription doses of 15 Gy for the first eight patients and 18 Gy for the remaining eight patients. Six (6) MV photon beams were designed to avoid the heart and contralateral breast. Optimization for IMRT and VMAT was performed to reduce the dose to the skin and normal breast. All plans were normalized such that 100% of the prescribed dose covered greater than 95% of the clinical target volume (CTV) consisting of gross tumor volume (GTV) plus 1.5 cm margin. Mean homogeneity index (HI) was the lowest (1.05 ± 0.02) for 3D CRT and the highest (1.11 ± 0.04) for VMAT. Mean conformity index (CI) was the lowest (1.42 ± 0.32) for IMRTNC and the highest (1.60 ± 0.32) for VMAT. Mean of the maximum point dose to skin was the lowest (73.7 ± 11.5%) for IMRTNC and the highest (86.5 ± 6.68%) for 3D CRT. IMRTCO showed very similar HI, CI, and maximum skin dose to IMRTNC (differences radiotherapy, we can conclude that noncoplanar or coplanar IMRT were optimal in this study as IMRT plans provided homogeneous and conformal target coverage, skin sparing, and relatively short treatment delivery time.

  16. Comparison of linear and angular measurements in CBCT scans using 2D and 3D rendering software

    Secil Aksoy


    Full Text Available The aim of this study was to compare the reliability of both linear and angular measurements conducted on two-dimensional (2D lateral cephalometric images and three-dimensional (3D cone-beam computed tomography-generated cephalograms derived from various rendering software. Pre-treatment cephalometric digital radiographs of 15 patients and their corresponding cone beam computed tomographic images were randomly selected. Vista Dent OC as 2D, In vivo 5.1.2, Maxilim and Romexis software were used to generate cephalograms from the CBCT scans (NewTom 3G, QR Verona, Italy. In total, 19 cephalometric landmarks were identified and 18 widely used (11 linear, 7 angular measurements were performed by an independent observer. Mann–Whitney and Kruskall–Wallis H tests were also used to compare the four methods (p 0.05. The ICCs for Vista Dent OC (2D measurements indicated high reproducibility (p < 0.05. The 2D and 3D generated cephalograms from various rendering software were found to be similar; however, measurements on curved surfaces are not easily reproducible for 3D software.

  17. Comparison of OpenFOAM and EllipSys3D for neutral atmospheric flow over complex terrain

    Cavar, Dalibor; Réthoré, Pierre-Elouan; Bechmann, Andreas;


    The flow solvers OpenFOAM and EllipSys3D are compared in the case of neutral atmospheric flow over terrain using the test cases of Askervein and Bolund hills. Both solvers are run using the steady-state Reynolds-averaged Navier–Stokes k– turbulence model. One of the main modeling differences...... between the two solvers is the wall-function approach. The Open-FOAM v.1.7.1 uses a Nikuradse’s sand roughness model, while EllipSys3D uses a model based on the atmospheric roughness length. It is found that Nikuradse’s model introduces an error dependent on the near-wall cell height. To mitigate...... this error the near-wall cells should be at least 10 times larger than the surface roughness. It is nonetheless possible to obtain very similar results between EllipSys3D and OpenFOAM v.1.7.1. The more recent OpenFOAM v.2.2.1, which includes the atmospheric roughness length wall-function approach, has also...

  18. Craniofacial vertical bone augmentation: a comparison between 3D printed monolithic monetite blocks and autologous onlay grafts in the rabbit.

    Tamimi, Faleh; Torres, Jesus; Gbureck, Uwe; Lopez-Cabarcos, Enrique; Bassett, David C; Alkhraisat, Mohammad H; Barralet, Jake E


    Onlay autografting is amongst the most predictable techniques for craniofacial vertical bone augmentation, however, complications related to donor site surgery are common and synthetic alternatives to onlay autografts are desirable. Recent studies have shown that the acidic calcium phosphates, brushite and monetite, are osteoconductive, osteoinductive and resorb faster in vivo than hydroxyapatite. Moreover, they can be 3D printed allowing precise host bone-implant conformation. The objectives of this study were to confirm that craniofacial screw fixation of 3D printed monetite blocks was possible and to compare the resulting vertical bone augmentation with autograft. 3D printed monolithic monetite onlay implants were fixed with osteosynthesis screws on the calvarial bone surface of New Zealand rabbits. After 8 weeks, integration between the implant and the calvarial bone surface was observed in all cases. Histomorphometry revealed that 42% of the monetite was resorbed and that the new bone formed within the implant occupied 43% of its volume, sufficient for immediate dental implant placement. Bone tissue within the autologous onlay occupied 60% of the volume. We observed that patterns of regeneration within the implants differed throughout the material and propose that this was due to the anatomy and blood supply pattern in the region. Rapid prototyped monetite being resorbable osteoconductive and osteoinductive would appear to be a promising biomaterial for many bone regeneration strategies.

  19. Comparison of 3D cube FLAIR with 2D FLAIR for multiple sclerosis imaging at 3 tesla

    Patzig, M.; Brueckmann, H.; Fesl, G. [Muenchen Univ. (Germany). Dept. of Neuroradiology; Burke, M. [GE Healthcare, Solingen (Germany)


    Purpose: Three-dimensional (3 D) MRI sequences allow improved spatial resolution with good signal and contrast properties as well as multiplanar reconstruction. We sought to compare Cube, a 3 D FLAIR sequence, to a standard 2 D FLAIR sequence in multiple sclerosis (MS) imaging. Materials and Methods: Examinations were performed in the clinical routine on a 3.0 Tesla scanner. 12 patients with definite MS were included. Lesions with MS-typical properties on the images of Cube FLAIR and 2 D FLAIR sequences were counted and allocated to different brain regions. Signal-to-noise ratios (SNR) and contrast-to-noise ratios (CNR) were calculated. Results: With 384 the overall number of lesions found with Cube FLAIR was significantly higher than with 2 D FLAIR (N = 221). The difference was mostly accounted for by supratentorial lesions (N = 372 vs. N = 216) while the infratentorial lesion counts were low in both sequences. SNRs and CNRs were significantly higher in CUBE FLAIR with the exception of the CNR of lesion to gray matter, which was not significantly different. Conclusion: Cube FLAIR showed a higher sensitivity for MS lesions compared to a 2 D FLAIR sequence. 3 D FLAIR might replace 2 D FLAIR sequences in MS imaging in the future. (orig.)

  20. Comparison of the PHISICS/RELAP5-3D Ring and Block Model Results for Phase I of the OECD MHTGR-350 Benchmark

    Gerhard Strydom


    The INL PHISICS code system consists of three modules providing improved core simulation capability: INSTANT (performing 3D nodal transport core calculations), MRTAU (depletion and decay heat generation) and a perturbation/mixer module. Coupling of the PHISICS code suite to the thermal hydraulics system code RELAP5-3D has recently been finalized, and as part of the code verification and validation program the exercises defined for Phase I of the OECD/NEA MHTGR 350 MW Benchmark were completed. This paper provides an overview of the MHTGR Benchmark, and presents selected results of the three steady state exercises 1-3 defined for Phase I. For Exercise 1, a stand-alone steady-state neutronics solution for an End of Equilibrium Cycle Modular High Temperature Reactor (MHTGR) was calculated with INSTANT, using the provided geometry, material descriptions, and detailed cross-section libraries. Exercise 2 required the modeling of a stand-alone thermal fluids solution. The RELAP5-3D results of four sub-cases are discussed, consisting of various combinations of coolant bypass flows and material thermophysical properties. Exercise 3 combined the first two exercises in a coupled neutronics and thermal fluids solution, and the coupled code suite PHISICS/RELAP5-3D was used to calculate the results of two sub-cases. The main focus of the paper is a comparison of the traditional RELAP5-3D “ring” model approach vs. a much more detailed model that include kinetics feedback on individual block level and thermal feedbacks on a triangular sub-mesh. The higher fidelity of the block model is illustrated with comparison results on the temperature, power density and flux distributions, and the typical under-predictions produced by the ring model approach are highlighted.

  1. Comparison of Shade Match Compatibility between Vitapan Classical and 3D Master Shade Guide Systems by Dental Students in Tabriz Faculty of Dentistry

    Ramin Negahdari


    Full Text Available Background and Aims: Dentists perform color-match process during indirect and direct restorations. Color research has shown that shade guides do not always match the color of natural teeth. Moreover, visual evaluation of dental colors has been found to be inconsistent and unreliable. In fact, it has always been important when using different shade guides. Our purpose in this study was to compare shade selection using two shade guide systems of Vitapan Classical and 3D Master by dental students of Tabriz University of Medical Sciences. Materials and methods: In this analytical, cross-sectional descriptive study, 20 male and 20 female senior dental students with a little clinical experience in working with shade guides were selected. Each student used two shade guides (Vitapan Classical and 3D Master separately for shade matching. Shade selection was randomly repeated one week later by the same protocol. T-test was used to compare repeatability of color matching (α=0.05. Comparison of the repeatability percentage was done with t-test. Results: Comparison of repeatability percentages of shade matching irrespective of gender showed that percentage of repeatability of shade match in 3D Master system was significantly high (P=0.00. In addition comparison of repeatability means of shade match with different shade guide systems on the basis of gender showed no significant differences (P=0.68. Conclusion: In general, the repeatability percentages of shade matching in 3D Master system was high and shade matching in females with this system was not different than males.   Key words: Color vision; indirect restorations; dental students

  2. Comparison of Different 2D and 3D-QSAR Methods on Activity Prediction of Histamine H3 Receptor Antagonists.

    Dastmalchi, Siavoush; Hamzeh-Mivehroud, Maryam; Asadpour-Zeynali, Karim


    Histamine H3 receptor subtype has been the target of several recent drug development programs. Quantitative structure-activity relationship (QSAR) methods are used to predict the pharmaceutically relevant properties of drug candidates whenever it is applicable. The aim of this study was to compare the predictive powers of three different QSAR techniques, namely, multiple linear regression (MLR), artificial neural network (ANN), and HASL as a 3D QSAR method, in predicting the receptor binding affinities of arylbenzofuran histamine H3 receptor antagonists. Genetic algorithm coupled partial least square as well as stepwise multiple regression methods were used to select a number of calculated molecular descriptors to be used in MLR and ANN-based QSAR studies. Using the leave-group-out cross-validation technique, the performances of the MLR and ANN methods were evaluated. The calculated values for the mean absolute percentage error (MAPE), ranging from 2.9 to 3.6, and standard deviation of error of prediction (SDEP), ranging from 0.31 to 0.36, for both MLR and ANN methods were statistically comparable, indicating that both methods perform equally well in predicting the binding affinities of the studied compounds toward the H3 receptors. On the other hand, the results from 3D-QSAR studies using HASL method were not as good as those obtained by 2D methods. It can be concluded that simple traditional approaches such as MLR method can be as reliable as those of more advanced and sophisticated methods like ANN and 3D-QSAR analyses.

  3. The Correlation Between the GFR and the Renal Dimensions in Glomerulopathy Patients: Comparison of 2D and 3D Ultrasound

    Kim, Gyoung Min [Seoul National University Hospital, Seoul (Korea, Republic of); Lee, Hak Jong; Hwang, Sung Il; Chin, Ho Jun [Seoul National University Bundang Hospital, Seongnam (Korea, Republic of)


    We wanted to determine the correlation between the renal length as measured on two dimensional (2D) ultrasonography (US) and the renal parenchymal volume as measured with a new three-dimensional (3D) volume probe ultrasound system. We also wanted to determine the correlation between the renal length or renal parenchymal volume and the glomerular filtration rate (GFR) in patients with glomerulopathy. From July 2007 to December 2007, 26 patients who were pathologically confirmed to have glomerulopathy by biopsy were enrolled. Renal length was measured with 2D US and the renal parenchymal volume was measured with 3D US just prior to biopsy. The GFR was obtained from the electronic medical records. Pearson's correlation coefficients were used to analyze the correlation between the renal length and the renal parenchymal volume, the correlation between the renal length and the GFR and the correlation between the renal parenchymal volume and the GFR. The renal length and the renal parenchymal volume showed strong positive correlation (r = 0.850, p = 0.0001). The correlation coefficient between the renal length and the GFR was 0.623 (p = 0.0007) and the correlation coefficient between the renal volume and the GFR was 0.590 (p = 0.0015). Both the renal length and renal parenchymal volume showed apparently positive correlations with the GFR in glomerulopathy patients. The renal length showed strong positive correlations with the renal parenchymal volume. Both the renal length and the renal parenchymal volume showed apparently positive correlations with the GFR in glomerulopathy patients. In glomerulopathy patients, the renal dimensions measured by ultrasound can reflect the status of the GFR, and the measurement of the 2D renal length could be sufficient for follow up. Further studies are needed to evaluate the role of 3D US for assessing patients with renal disease

  4. 3D kinematic in-vitro comparison of posterolateral corner reconstruction techniques in a combined injury model.

    Nau, Thomas; Chevalier, Yan; Hagemeister, Nicola; Duval, Nicolas; deGuise, Jacques A


    With the variable injury pattern to the posterolateral structures (PLS) of the knee, a number of reconstructive procedures have been introduced. It was the aim of the present study to evaluate the resulting 3D kinematics following three different surgical techniques of reconstruction in a combined posterior cruciate ligament (PCL)/PLS injury model. In nine human cadaveric knees, 3D kinematics were recorded during the path of flexion-extension using a computer based custom made 6-degree-of-freedom (DOF) testing apparatus. Additional laxity tests were conducted at 30 and 90 degrees of flexion. Testing was performed before and after cutting the PLS and PCL, followed by PCL reconstruction alone. Reconstructing the posterolateral corner, three surgical techniques were compared: (a) the posterolateral corner sling procedure (PLCS), (b) the biceps tenodesis (BT), and (c) a bone patellar-tendon bone (BTB) allograft reconstruction. Posterior as well as rotational laxity were significantly increased after PCL/PLS transection at 30 and 90 degrees of flexion. Isolated PCL reconstruction resulted in a remaining external rotational deficiency for both tested flexion angles. Additional PLS reconstruction closely restored external rotation as well as posterior translation to intact values by all tested procedures. Compared to the intact knee, dynamic testing revealed a significant internal tibial rotation for (b) BT (mean=3.9 degrees, p=0.043) and for (c) BTB allograft (mean=4.3 degrees, p=0.012). (a) The PLCS demonstrated a tendency to internal tibial rotation between 0 and 60 degrees of flexion (mean=2.2 degrees, p=0.079). Varus/valgus rotation as well as anterior/posterior translation did not show significant differences for any of the tested techniques. The present study shows that despite satisfying results in static laxity testing, pathological 3D knee kinematics were not restored to normal, demonstrated by a nonphysiological internal tibial rotation during the path of

  5. Experimental comparison of 2D and 3D technology mediated paramedic-physician collaboration in remote emergency medical situations

    Sonnenwald, Diane H.; Maurin, Hanna; Cairns, Bruce


    and remote, consulting physician. Post-questionnaire data illustrate that the information provided by the consulting physician was perceived to be more useful by the paramedic in the 3D condition than the 2D condition. However, the data pertaining to the quality of interaction and trust between...... techniques. This may be of benefit in diagnosing and treating patients in emergency situations where specialized medical expertise is not locally available. We conducted an experimental evaluation, simulating an emergency medical situation and examining the interaction between the attending paramedic...... the consulting physician and paramedic showed mixed results. The implications of these results are discussed....

  6. 3D nanoimprint for NIR Fabry-Pérot filter arrays: fabrication, characterization and comparison of different cavity designs

    Nguyen, Duc Toan; Ababtain, Muath; Memon, Imran; Ullah, Anayat; Istock, André; Woidt, Carsten; Xie, Weichang; Lehmann, Peter; Hillmer, Hartmut


    We report on the fabrication of miniaturized NIR spectrometers based on arrays of multiple Fabry-Pérot (FP) filters. The various cavities of different height are fabricated via a single patterning step using high resolution 3D nanoimprint technology. Today, low-cost patterning of extended cavity heights for NIR filters using the conventional spin-coated nanoimprint methodology is not available because of insufficient coating layers and low mobility of the resist materials to fill extended cavity structures. Our investigation focuses on reducing the technological effort for fabrication of homogeneous extended cavities. We study alternative cavity designs, including a new resist and apply large-area 3D nanoimprint based on hybrid mold and UV Substrate Conformal Imprint Lithography (UV-SCIL) to overcome these limitations. We compare three different solutions, i.e. (1) applying multiple spin coating of the resist to obtain thicker initial resist layers, (2) introducing a hybrid cavity (combination of a thin oxide layer and the organic cavity) to compensate the height differences, and (3) optimizing the imprint process with a novel resist material. The imprint results based on these methods demonstrate the implementation of NIR FP filters with high transmission intensity (best single filter transmission >90 %) and small line widths (<5 nm in full width at half maximum).

  7. Comparison of different approaches of estimating effective dose from reported exposure data in 3D imaging with interventional fluoroscopy systems

    Svalkvist, Angelica; Hansson, Jonny; Bâth, Magnus


    Three-dimensional (3D) imaging with interventional fluoroscopy systems is today a common examination. The examination includes acquisition of two-dimensional projection images, used to reconstruct section images of the patient. The aim of the present study was to investigate the difference in resulting effective dose obtained using different levels of complexity in calculations of effective doses from these examinations. In the study the Siemens Artis Zeego interventional fluoroscopy system (Siemens Medical Solutions, Erlangen, Germany) was used. Images of anthropomorphic chest and pelvis phantoms were acquired. The exposure values obtained were used to calculate the resulting effective doses from the examinations, using the computer software PCXMC (STUK, Helsinki, Finland). The dose calculations were performed using three different methods: 1. using individual exposure values for each projection image, 2. using the mean tube voltage and the total DAP value, evenly distributed over the projection images, and 3. using the mean kV and the total DAP value, evenly distributed over smaller selection of projection images. The results revealed that the difference in resulting effective dose between the first two methods was smaller than 5%. When only a selection of projection images were used in the dose calculations the difference increased to over 10%. Given the uncertainties associated with the effective dose concept, the results indicate that dose calculations based on average exposure values distributed over a smaller selection of projection angles can provide reasonably accurate estimations of the radiation doses from 3D imaging using interventional fluoroscopy systems.

  8. 3D nanoimprint for NIR Fabry-Pérot filter arrays: fabrication, characterization and comparison of different cavity designs

    Duc Toan Nguyen


    Full Text Available Abstract We report on the fabrication of miniaturized NIR spectrometers based on arrays of multiple Fabry-Pérot (FP filters. The various cavities of different height are fabricated via a single patterning step using high resolution 3D nanoimprint technology. Today, low-cost patterning of extended cavity heights for NIR filters using the conventional spin-coated nanoimprint methodology is not available because of insufficient coating layers and low mobility of the resist materials to fill extended cavity structures. Our investigation focuses on reducing the technological effort for fabrication of homogeneous extended cavities. We study alternative cavity designs, including a new resist and apply large-area 3D nanoimprint based on hybrid mold and UV Substrate Conformal Imprint Lithography (UV-SCIL to overcome these limitations. We compare three different solutions, i.e. (1 applying multiple spin coating of the resist to obtain thicker initial resist layers, (2 introducing a hybrid cavity (combination of a thin oxide layer and the organic cavity to compensate the height differences, and (3 optimizing the imprint process with a novel resist material. The imprint results based on these methods demonstrate the implementation of NIR FP filters with high transmission intensity (best single filter transmission >90 % and small line widths (<5 nm in full width at half maximum.

  9. A comparison study of atlas-based 3D cardiac MRI segmentation: global versus global and local transformations

    Daryanani, Aditya; Dangi, Shusil; Ben-Zikri, Yehuda Kfir; Linte, Cristian A.


    Magnetic Resonance Imaging (MRI) is a standard-of-care imaging modality for cardiac function assessment and guidance of cardiac interventions thanks to its high image quality and lack of exposure to ionizing radiation. Cardiac health parameters such as left ventricular volume, ejection fraction, myocardial mass, thickness, and strain can be assessed by segmenting the heart from cardiac MRI images. Furthermore, the segmented pre-operative anatomical heart models can be used to precisely identify regions of interest to be treated during minimally invasive therapy. Hence, the use of accurate and computationally efficient segmentation techniques is critical, especially for intra-procedural guidance applications that rely on the peri-operative segmentation of subject-specific datasets without delaying the procedure workflow. Atlas-based segmentation incorporates prior knowledge of the anatomy of interest from expertly annotated image datasets. Typically, the ground truth atlas label is propagated to a test image using a combination of global and local registration. The high computational cost of non-rigid registration motivated us to obtain an initial segmentation using global transformations based on an atlas of the left ventricle from a population of patient MRI images and refine it using well developed technique based on graph cuts. Here we quantitatively compare the segmentations obtained from the global and global plus local atlases and refined using graph cut-based techniques with the expert segmentations according to several similarity metrics, including Dice correlation coefficient, Jaccard coefficient, Hausdorff distance, and Mean absolute distance error.

  10. Plasma response measurements of external magnetic perturbations using electron cyclotron emission and comparisons to 3D ideal MHD equilibrium

    Willensdorfer, M; Strumberger, E; Suttrop, W; Vanovac, B; Brida, D; Cavedon, M; Classen, I; Dunne, M; Fietz, S; Fischer, R; Kirk, A; Laggner, F M; Liu, Y Q; Odstrcil, T; Ryan, D A; Viezzer, E; Zohm, H; Luhmann, I C


    The plasma response from an external n = 2 magnetic perturbation field in ASDEX Upgrade has been measured using mainly electron cyclotron emission (ECE) diagnostics and a rigid rotating field. To interpret ECE and ECE-imaging (ECE-I) measurements accurately, forward modeling of the radiation transport has been combined with ray tracing. The measured data is compared to synthetic ECE data generated from a 3D ideal magnetohydrodynamics (MHD) equilibrium calculated by VMEC. The measured amplitudes of the helical displacement in the midplane are in reasonable agreement with the one from the synthetic VMEC diagnostics. Both exceed the vacuum field calculations and indicate the presence of an amplified kink response at the edge. Although the calculated magnetic structure of this edge kink peaks at poloidal mode numbers larger than the resonant components |m| > |nq|, the displacement measured by ECE-I is almost resonant |m| ~ |nq|. This is expected from ideal MHD in the proximity of rational surfaces. VMEC and MARS-...

  11. Comparison of "warm and wet" and "cold and icy" scenarios for early Mars in a 3D climate model

    Wordsworth, Robin D; Pierrehumbert, Raymond T; Forget, Francois; Head, James W


    We use a 3D general circulation model to compare the primitive Martian hydrological cycle in "warm and wet" and "cold and icy" scenarios. In the warm and wet scenario, an anomalously high solar flux or intense greenhouse warming artificially added to the climate model are required to maintain warm conditions and an ice-free northern ocean. Precipitation shows strong surface variations, with high rates around Hellas basin and west of Tharsis but low rates around Margaritifer Sinus (where the observed valley network drainage density is nonetheless high). In the cold and icy scenario, snow migration is a function of both obliquity and surface pressure, and limited episodic melting is possible through combinations of seasonal, volcanic and impact forcing. At surface pressures above those required to avoid atmospheric collapse (~0.5 bar) and moderate to high obliquity, snow is transported to the equatorial highland regions where the concentration of valley networks is highest. Snow accumulation in the Aeolis quadr...

  12. Relativistic radiation belt electron responses to GEM magnetic storms: Comparison of CRRES observations with 3-D VERB simulations

    Kim, Kyung-Chan; Shprits, Yuri; Subbotin, Dmitriy; Ni, Binbin


    Understanding the dynamics of relativistic electron acceleration, loss, and transport in the Earth's radiation belt during magnetic storms is a challenging task. The U.S. National Science Foundation's Geospace Environment Modeling (GEM) has identified five magnetic storms for in-depth study that occurred during the second half of the Combined Release and Radiation Effects Satellite (CRRES) mission in the year 1991. In this study, we show the responses of relativistic radiation belt electrons to the magnetic storms by comparing the time-dependent 3-D Versatile Electron Radiation Belt (VERB) simulations with the CRRES MEA 1 MeV electron observations in order to investigate the relative roles of the competing effects of previously proposed scattering mechanisms at different storm phases, as well as to examine the extent to which the simulations can reproduce observations. The major scattering processes in our model are radial transport due to Ultra Low Frequency (ULF) electromagnetic fluctuations, pitch angle and energy diffusion including mixed diffusion by whistler mode chorus waves outside the plasmasphere, and pitch angle scattering by plasmaspheric hiss inside the plasmasphere. The 3-D VERB simulations show that during the storm main phase and early recovery phase the estimated plasmapause is located deep in the inner region, indicating that pitch angle scattering by chorus waves can be a dominant loss process in the outer belt. We have also confirmed the important role played by mixed energy-pitch angle diffusion by chorus waves, which tends to reduce the fluxes enhanced by local acceleration, resulting in comparable levels of computed and measured fluxes. However, we cannot reproduce the more pronounced flux dropout near the boundary of our simulations during the main phase, which indicates that non-adiabatic losses may extend toL-shells lower than our simulation boundary. We also provide a detailed description of simulations for each of the GEM storm events.

  13. Technical note: Criterion validity of whole body surface area equations: a comparison using 3D laser scanning.

    Daniell, Nathan; Olds, Timothy; Tomkinson, Grant


    Measurements of whole body surface area (WBSA) have important applications in numerous fields including biological anthropology, clinical medicine, biomechanics, and sports science. Currently, WBSA is most often estimated using predictive equations due to the complex and time consuming methods required for direct measurement. The main aim of this study was to identify whether there were significant and meaningful differences between WBSA measurements taken using a whole body three-dimensional (3D) scanner (criterion measure) and the estimates derived from each WBSA equation identified from a systematic review. The study also aimed to determine whether differences varied according to body mass index (BMI), sex, or athletic status. Fifteen WBSA equations were compared with direct measurements taken on 1,714 young adult subjects, aged 18-30 years, using the Vitus Smart 3D whole body scanner, including 1,452 subjects (753 males, 699 females) from the general Australian population and 262 rowers (148 males, 114 females). Mixed-design analysis of variances determined significant differences and accuracy was quantified using Bland-Altman analysis and effect sizes. Thirteen of the 15 equations overestimated WBSA. With a few exceptions, equations were accurate with a low-systematic error (bias ≤2%) and low-random error (standard deviation of the differences 1.5-3.0%). However, BMI did have a substantial impact with the accuracy of some WBSA equations varying between the four BMI categories. The Shuter and Aslani: Eur J Appl Physiol 82 (2000) 250-254 equation was identified as the most accurate equation and should be used for Western populations 18-30 years of age. Care must be taken when deciding which equation to use when estimating WBSA.

  14. Comparison of 3D point clouds obtained by photogrammetric UAVs and TLS to determine the attitude of dolerite outcrops discontinuities.

    Duarte, João; Gonçalves, Gil; Duarte, Diogo; Figueiredo, Fernando; Mira, Maria


    Photogrammetric Unmanned Aerial Vehicles (UAVs) and Terrestrial Laser Scanners (TLS) are two emerging technologies that allows the production of dense 3D point clouds of the sensed topographic surfaces. Although image-based stereo-photogrammetric point clouds could not, in general, compete on geometric quality over TLS point clouds, fully automated mapping solutions based on ultra-light UAVs (or drones) have recently become commercially available at very reasonable accuracy and cost for engineering and geological applications. The purpose of this paper is to compare the two point clouds generated by these two technologies, in order to automatize the manual process tasks commonly used to detect and represent the attitude of discontinuities (Stereographic projection: Schmidt net - Equal area). To avoid the difficulties of access and guarantee the data survey security conditions, this fundamental step in all geological/geotechnical studies, applied to the extractive industry and engineering works, has to be replaced by a more expeditious and reliable methodology. This methodology will allow, in a more actuated clear way, give answers to the needs of evaluation of rock masses, by mapping the structures present, which will reduce considerably the associated risks (investment, structures dimensioning, security, etc.). A case study of a dolerite outcrop locate in the center of Portugal (the dolerite outcrop is situated in the volcanic complex of Serra de Todo-o-Mundo, Casais Gaiola, intruded in Jurassic sandstones) will be used to assess this methodology. The results obtained show that the 3D point cloud produced by the Photogrammetric UAV platform has the appropriate geometric quality for extracting the parameters that define the discontinuities of the dolerite outcrops. Although, they are comparable to the manual extracted parameters, their quality is inferior to parameters extracted from the TLS point cloud.

  15. A dosimetric comparison of 3D-CRT, IMRT, and static tomotherapy with an SIB for large and small breast volumes

    Michalski, Andrea [Department of Health Science (MRS), The University of Sydney, Lidcombe, New South Wales (Australia); Central Coast Cancer Centre, Gosford Hospital, Gosford, New South Wales (Australia); Atyeo, John, E-mail: [Department of Health Science (MRS), The University of Sydney, Lidcombe, New South Wales (Australia); Cox, Jennifer [Department of Health Science (MRS), The University of Sydney, Lidcombe, New South Wales (Australia); Department of Radiation Oncology, Royal North Shore Hospital, St Leonards, New South Wales (Australia); Rinks, Marianne [Department of Health Science (MRS), The University of Sydney, Lidcombe, New South Wales (Australia); Radiation Oncology, Cancer Services, Illawarra Shoalhaven Local Health District, Wollongong, New South Wales (Australia); Morgia, Marita; Lamoury, Gillian [Department of Radiation Oncology, Royal North Shore Hospital, St Leonards, New South Wales (Australia)


    Radiation therapy to the breast is a complex task, with many different techniques that can be employed to ensure adequate dose target coverage while minimizing doses to the organs at risk. This study compares the dose planning outcomes of 3 radiation treatment modalities, 3 dimensional conformal radiation therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), and static tomotherapy, for left-sided whole-breast radiation treatment with a simultaneous integrated boost (SIB). Overall, 20 patients with left-sided breast cancer were separated into 2 cohorts, small and large, based on breast volume. Dose plans were produced for each patient using 3D-CRT, IMRT, and static tomotherapy. All patients were prescribed a dose of 45 Gy in 20 fractions to the breast with an SIB of 56 Gy in 20 fractions to the tumor bed and normalized so that D{sub 98%} > 95% of the prescription dose. Dosimetric comparisons were made between the 3 modalities and the interaction of patient size. All 3 modalities offered adequate planning target volume (PTV) coverage with D{sub 98%} > 95% and D{sub 2%} < 107%. Static tomotherapy offered significantly improved (p = 0.006) dose homogeneity to the PTV{sub boost} {sub eval} (0.079 ± 0.011) and breast minus the SIB volume (Breast{sub SIB}) (p < 0.001, 0.15 ± 0.03) compared with the PTV{sub boost} {sub eval} (0.085 ± 0.008, 0.088 ± 0.12) and Breast{sub SIB} (0.22 ± 0.05, 0.23 ± 0.03) for IMRT and 3D-CRT, respectively. Static tomotherapy also offered statistically significant reductions (p < 0.001) in doses to the ipsilateral lung mean dose of 6.79 ± 2.11 Gy compared with 7.75 ± 2.54 Gy and 8.29 ± 2.76 Gy for IMRT and 3D-CRT, respectively, and significantly (p < 0.001) reduced heart doses (mean = 2.83 ± 1.26 Gy) compared to both IMRT and 3D-CRT (mean = 3.70 ± 1.44 Gy and 3.91 ± 1.58 Gy). Static tomotherapy is the dosimetrically superior modality for the whole breast with an SIB compared with IMRT and 3D-CRT. IMRT is superior to 3D

  16. Volumetric LiDAR scanning of a wind turbine wake and comparison with a 3D analytical wake model

    Carbajo Fuertes, Fernando; Porté-Agel, Fernando


    A correct estimation of the future power production is of capital importance whenever the feasibility of a future wind farm is being studied. This power estimation relies mostly on three aspects: (1) a reliable measurement of the wind resource in the area, (2) a well-established power curve of the future wind turbines and, (3) an accurate characterization of the wake effects; the latter being arguably the most challenging one due to the complexity of the phenomenon and the lack of extensive full-scale data sets that could be used to validate analytical or numerical models. The current project addresses the problem of obtaining a volumetric description of a full-scale wake of a 2MW wind turbine in terms of velocity deficit and turbulence intensity using three scanning wind LiDARs and two sonic anemometers. The characterization of the upstream flow conditions is done by one scanning LiDAR and two sonic anemometers, which have been used to calculate incoming vertical profiles of horizontal wind speed, wind direction and an approximation to turbulence intensity, as well as the thermal stability of the atmospheric boundary layer. The characterization of the wake is done by two scanning LiDARs working simultaneously and pointing downstream from the base of the wind turbine. The direct LiDAR measurements in terms of radial wind speed can be corrected using the upstream conditions in order to provide good estimations of the horizontal wind speed at any point downstream of the wind turbine. All this data combined allow for the volumetric reconstruction of the wake in terms of velocity deficit as well as turbulence intensity. Finally, the predictions of a 3D analytical model [1] are compared to the 3D LiDAR measurements of the wind turbine. The model is derived by applying the laws of conservation of mass and momentum and assuming a Gaussian distribution for the velocity deficit in the wake. This model has already been validated using high resolution wind-tunnel measurements

  17. Stationary versus non-stationary (13)C-MFA: a comparison using a consistent dataset.

    Noack, Stephan; Nöh, Katharina; Moch, Matthias; Oldiges, Marco; Wiechert, Wolfgang


    Besides the well-established (13)C-metabolic flux analysis ((13)C-MFA) which characterizes a cell's fluxome in a metabolic and isotopic stationary state a current area of research is isotopically non-stationary MFA. Non-stationary (13)C-MFA uses short-time isotopic transient data instead of long-time isotopic equilibrium data and thus is capable to resolve fluxes within much shorter labeling experiments. However, a comparison of both methods with data from one single experiment has not been made so far. In order to create a consistent database for directly comparing both methods a (13)C-labeling experiment in a fed-batch cultivation with a Corynebacterium glutamicum lysine producer was carried out. During the experiment the substrate glucose was switched from unlabeled to a specifically labeled glucose mixture which was immediately traced by fast sampling and metabolite quenching. The time course of labeling enrichments in intracellular metabolites until isotopic stationarity was monitored by LC-MS/MS. The resulting dataset was evaluated using the classical as well as the isotopic non-stationary MFA approach. The results show that not only the obtained relative data, i.e. intracellular flux distributions, but also the more informative quantitative fluxome data significantly depend on the combination of the measurements and the underlying modeling approach used for data integration. Taking further criteria on the experimental and computational part into consideration, the current limitations of both methods are demonstrated and possible pitfalls are concluded.

  18. Simulations of a rotor with active deformable trailing edge flaps in half-wake inflow: Comparison of EllipSys 3D with HAWC2

    Barlas, Thanasis K.; Zahle, Frederik; Sørensen, Niels N.;


    . In this study, a comparison between aerodynamic predictions of the aeroelastic code HAWC2 and the Navier-Stokes code EllipSys3D for the NREL 5MW reference wind turbine rotor in a stiff configuration equipped with a deformable trailing edge flap is performed. A case where the half rotor plane experiences...... an inflow resembling the wake from an upstream wind turbine is investigated, which is appropriate for comparing the predictions of the two codes related to the abrupt aerodynamic response and the influence of the controllable flap. The trailing edge flap is actuated to alleviate the added loads from a non...

  19. Hydrodynamic modelling of dense gas-fluidised beds: comparison and validation of 3D discrete particle and continuum models

    Goldschmidt, M.J.V.; Beetstra, R.; Kuipers, J.A.M.


    A critical comparison of a hard-sphere discrete particle model, a two-fluid model with kinetic theory closure equations and experiments performed in a pseudo-two-dimensional gas-fluidised bed is made. Bubble patterns, time-averaged particle distributions and bed expansion dynamics measured with a no

  20. ASTRID: A 3D Eulerian software for subcooled boiling modelling - comparison with experimental results in tubes and annuli

    Briere, E.; Larrauri, D.; Olive, J. [Electricite de France, Chatou (France)


    For about four years, Electricite de France has been developing a 3-D computer code for the Eulerian simulation of two-phase flows. This code, named ASTRID, is based on the six-equation two-fluid model. Boiling water flows, such as those encountered in nuclear reactors, are among the main applications of ASTRID. In order to provide ASTRID with closure laws and boundary conditions suitable for boiling flows, a boiling model has been developed by EDF and the Institut de Mecanique des Fluides de Toulouse. In the fluid, the heat and mass transfer between a bubble and the liquid is being modelled. At the heating wall, the incipient boiling point is determined according to Hsu`s criterion and the boiling heat flux is split into three additive terms: a convective term, a quenching term and a vaporisation term. This model uses several correlations. EDF`s program in boiling two-phase flows also includes experimental studies, some of which are performed in collaboration with other laboratories. Refrigerant subcooled boiling both in tubular (DEBORA experiment, CEN Grenoble) and in annular geometry (Arizona State University Experiment) have been computed with ASTRID. The simulations show the satisfactory results already obtained on void fraction and liquid temperature. Ways of improvement of the model are drawn especially on the dynamical part.

  1. Comparison of experimental data and 3D simulations of ion beam neutralization from the neutralized transport experiment

    Thoma, C.; Welch, D.R.; Yu, S.S.; Henestroza, E.; Roy, P.K.; Eylon, S.; Gilson, E.P.


    The Neutralized Transport Experiment (NTX) at Lawrence Berkeley National Laboratory has been designed to study the final focus and neutralization of high perveance ion beams for applications in heavy ion fusion (HIF) and high energy density physics (HEDP) experiments. Pre-formed plasmas in the last meter before the target of the scaled experiment provide a source of electrons which neutralize the ion current and prevent the space-charge induced spreading of the beam spot. NTX physics issues are discussed and experimental data is analyzed and compared with 3D particle-in-cell simulations. Along with detailed target images, 4D phase-space data of the NTX at the entrance of the neutralization region has been acquired. This data is used to provide a more accurate beam distribution with which to initialize the simulation. Previous treatments have used various idealized beam distributions which lack the detailed features of the experimental ion beam images. Simulation results are compared with NTX experimental measurements for 250 keV K{sup +} ion beams with dimensionless perveance of 1-7 x 10{sup -4}. In both simulation and experiment, the deduced beam charge neutralization is close to the predicted maximum value.

  2. Radionuclide transport and uptake in coastal aquatic ecosystems: a comparison of a 3D dynamic model and a compartment model.

    Erichsen, Anders Christian; Konovalenko, Lena; Møhlenberg, Flemming; Closter, Rikke Margrethe; Bradshaw, Clare; Aquilonius, Karin; Kautsky, Ulrik


    In safety assessments of underground radioactive waste repositories, understanding radionuclide fate in ecosystems is necessary to determine the impacts of potential releases. Here, the reliability of two mechanistic models (the compartmental K-model and the 3D dynamic D-model) in describing the fate of radionuclides released into a Baltic Sea bay is tested. Both are based on ecosystem models that simulate the cycling of organic matter (carbon). Radionuclide transfer is linked to adsorption and flows of carbon in food chains. Accumulation of Th-230, Cs-135, and Ni-59 in biological compartments was comparable between the models and site measurements despite differences in temporal resolution, biological state variables, and partition coefficients. Both models provided confidence limits for their modeled concentration ratios, an improvement over models that only estimate means. The D-model enables estimates at high spatio-temporal resolution. The K-model, being coarser but faster, allows estimates centuries ahead. Future developments could integrate the two models to take advantage of their respective strengths.

  3. Radionuclide Transport and Uptake in Coastal Aquatic Ecosystems: A Comparison of a 3D Dynamic Model and a Compartment Model

    Erichsen, Anders Christian; Moehlenberg, Flemming; Closter, Rikke Margrethe [Ecological and Environmental Dept., DHI, Hoersholm (Denmark)], E-mail:; Konovalenko, Lena; Bradshaw, Clare [The Dept. of Ecology, Environment and Plant Sciences, Stockholm Univ., Stockholm (Sweden); Kautsky, Ulrik [Swedish Nuclear Fuel and Waste Management Co. (SKB), Stockholm (Sweden); Aquilonius, Karin [Studsvik Nuclear AB, Nykoeping (Sweden)


    In safety assessments of underground radioactive waste repositories, understanding radionuclide fate in ecosystems is necessary to determine the impacts of potential releases. Here, the reliability of two mechanistic models (the compartmental K-model and the 3D dynamic D-model) in describing the fate of radionuclides released into a Baltic Sea bay is tested. Both are based on ecosystem models that simulate the cycling of organic matter (carbon). Radionuclide transfer is linked to adsorption and flows of carbon in food chains. Accumulation of Th-230, Cs-135, and Ni-59 in biological compartments was comparable between the models and site measurements despite differences in temporal resolution, biological state variables, and partition coefficients. Both models provided confidence limits for their modeled concentration ratios, an improvement over models that only estimate means. The D-model enables estimates at high spatio-temporal resolution. The K-model, being coarser but faster, allows estimates centuries ahead. Future developments could integrate the two models to take advantage of their respective strengths.

  4. Comparison of 3D Adaptive Remeshing Strategies for Finite Element Simulations of Electromagnetic Heating of Gold Nanoparticles

    Fadhil Mezghani


    Full Text Available The optical properties of metallic nanoparticles are well known, but the study of their thermal behavior is in its infancy. However the local heating of surrounding medium, induced by illuminated nanostructures, opens the way to new sensors and devices. Consequently the accurate calculation of the electromagnetically induced heating of nanostructures is of interest. The proposed multiphysics problem cannot be directly solved with the classical refinement method of Comsol Multiphysics and a 3D adaptive remeshing process based on an a posteriori error estimator is used. In this paper the efficiency of three remeshing strategies for solving the multiphysics problem is compared. The first strategy uses independent remeshing for each physical quantity to reach a given accuracy. The second strategy only controls the accuracy on temperature. The third strategy uses a linear combination of the two normalized targets (the electric field intensity and the temperature. The analysis of the performance of each strategy is based on the convergence of the remeshing process in terms of number of elements. The efficiency of each strategy is also characterized by the number of computation iterations, the number of elements, the CPU time, and the RAM required to achieve a given target accuracy.

  5. Optimization and comparison of two different 3D culture methods to prepare cell aggregates as a bioink for organ printing.

    Imani, Rana; Hojjati Emami, Shahriar; Fakhrzadeh, Hossein; Baheiraei, Nafiseh; Sharifi, Ali M


    The ultimate goal of tissue engineering is to design and fabricate functional human tissues that are similar to natural cells and are capable of regeneration. Preparation of cell aggregates is one of the important steps in 3D tissue engineering technology, particularly in organ printing. Two simple methods, hanging drop (HD) and conical tube (CT) were utilized to prepare cell aggregates. The size and viability of the aggregates obtained at different initial cell densities and pre-culture duration were compared. The proliferative ability of the cell aggregates and their ability to spread in culture plates were also investigated. In both methods, the optimum average size of the aggregates was less than 500 microm. CT aggregates were smaller than HD aggregates. 5,000 cells per drop HD aggregates showed a marked ability to attach and spread on the culture surface. The proliferative ability reduced when the initial cell density was increased. Comparing these methods, we found that the HD method having better size controlling ability as well as enhanced ability to maintain higher rates of viability, spreading, and proliferation. In conclusion, smaller HD aggregates might be a suitable choice as building blocks for making bioink particles in bioprinting technique.

  6. A Sensory 3D Map of the Odor Description Space Derived from a Comparison of Numeric Odor Profile Databases.

    Zarzo, Manuel


    Many authors have proposed different schemes of odor classification, which are useful to aid the complex task of describing smells. However, reaching a consensus on a particular classification seems difficult because our psychophysical space of odor description is a continuum and is not clustered into well-defined categories. An alternative approach is to describe the perceptual space of odors as a low-dimensional coordinate system. This idea was first proposed by Crocker and Henderson in 1927, who suggested using numeric profiles based on 4 dimensions: "fragrant," "acid," "burnt," and "caprylic." In the present work, the odor profiles of 144 aroma chemicals were compared by means of statistical regression with comparable numeric odor profiles obtained from 2 databases, enabling a plausible interpretation of the 4 dimensions. Based on the results and taking into account comparable 2D sensory maps of odor descriptors from the literature, a 3D sensory map (odor cube) has been drawn up to improve understanding of the similarities and dissimilarities of the odor descriptors most frequently used in fragrance chemistry.

  7. Uav-Based Acquisition of 3d Point Cloud - a Comparison of a Low-Cost Laser Scanner and Sfm-Tools

    Mader, D.; Blaskow, R.; Westfeld, P.; Maas, H.-G.


    The Project ADFEX (Adaptive Federative 3D Exploration of Multi Robot System) pursues the goal to develop a time- and cost-efficient system for exploration and monitoring task of unknown areas or buildings. A fleet of unmanned aerial vehicles equipped with appropriate sensors (laser scanner, RGB camera, near infrared camera, thermal camera) were designed and built. A typical operational scenario may include the exploration of the object or area of investigation by an UAV equipped with a laser scanning range finder to generate a rough point cloud in real time to provide an overview of the object on a ground station as well as an obstacle map. The data about the object enables the path planning for the robot fleet. Subsequently, the object will be captured by a RGB camera mounted on the second flying robot for the generation of a dense and accurate 3D point cloud by using of structure from motion techniques. In addition, the detailed image data serves as basis for a visual damage detection on the investigated building. This paper focuses on our experience with use of a low-cost light-weight Hokuyo laser scanner onboard an UAV. The hardware components for laser scanner based 3D point cloud acquisition are discussed, problems are demonstrated and analyzed, and a quantitative analysis of the accuracy potential is shown as well as in comparison with structure from motion-tools presented.

  8. 3D Animation Essentials

    Beane, Andy


    The essential fundamentals of 3D animation for aspiring 3D artists 3D is everywhere--video games, movie and television special effects, mobile devices, etc. Many aspiring artists and animators have grown up with 3D and computers, and naturally gravitate to this field as their area of interest. Bringing a blend of studio and classroom experience to offer you thorough coverage of the 3D animation industry, this must-have book shows you what it takes to create compelling and realistic 3D imagery. Serves as the first step to understanding the language of 3D and computer graphics (CG)Covers 3D anim

  9. 3D video

    Lucas, Laurent; Loscos, Céline


    While 3D vision has existed for many years, the use of 3D cameras and video-based modeling by the film industry has induced an explosion of interest for 3D acquisition technology, 3D content and 3D displays. As such, 3D video has become one of the new technology trends of this century.The chapters in this book cover a large spectrum of areas connected to 3D video, which are presented both theoretically and technologically, while taking into account both physiological and perceptual aspects. Stepping away from traditional 3D vision, the authors, all currently involved in these areas, provide th

  10. 3D vision system assessment

    Pezzaniti, J. Larry; Edmondson, Richard; Vaden, Justin; Hyatt, Bryan; Chenault, David B.; Kingston, David; Geulen, Vanilynmae; Newell, Scott; Pettijohn, Brad


    In this paper, we report on the development of a 3D vision system consisting of a flat panel stereoscopic display and auto-converging stereo camera and an assessment of the system's use for robotic driving, manipulation, and surveillance operations. The 3D vision system was integrated onto a Talon Robot and Operator Control Unit (OCU) such that direct comparisons of the performance of a number of test subjects using 2D and 3D vision systems were possible. A number of representative scenarios were developed to determine which tasks benefited most from the added depth perception and to understand when the 3D vision system hindered understanding of the scene. Two tests were conducted at Fort Leonard Wood, MO with noncommissioned officers ranked Staff Sergeant and Sergeant First Class. The scenarios; the test planning, approach and protocols; the data analysis; and the resulting performance assessment of the 3D vision system are reported.

  11. Optimized Volumetric Modulated Arc Therapy Versus 3D-CRT for Early Stage Mediastinal Hodgkin Lymphoma Without Axillary Involvement: A Comparison of Second Cancers and Heart Disease Risk

    Filippi, Andrea Riccardo, E-mail: [Department of Oncology, Radiation Oncology, University of Torino, Torino (Italy); Ragona, Riccardo; Piva, Cristina; Scafa, Davide; Fiandra, Christian [Department of Oncology, Radiation Oncology, University of Torino, Torino (Italy); Fusella, Marco; Giglioli, Francesca Romana [Medical Physics, AOU Città della Salute e della Scienza Hospital, Torino (Italy); Lohr, Frank [Department of Radiation Oncology, University Medical Center Mannheim, University of Heidelberg, Mannheim (Germany); Ricardi, Umberto [Department of Oncology, Radiation Oncology, University of Torino, Torino (Italy)


    Purpose: The purpose of this study was to evaluate the risks of second cancers and cardiovascular diseases associated with an optimized volumetric modulated arc therapy (VMAT) planning solution in a selected cohort of stage I/II Hodgkin lymphoma (HL) patients treated with either involved-node or involved-site radiation therapy in comparison with 3-dimensional conformal radiation therapy (3D-CRT). Methods and Materials: Thirty-eight patients (13 males and 25 females) were included. Disease extent was mediastinum alone (n=8, 21.1%); mediastinum plus unilateral neck (n=19, 50%); mediastinum plus bilateral neck (n=11, 29.9%). Prescription dose was 30 Gy in 2-Gy fractions. Only 5 patients had mediastinal bulky disease at diagnosis (13.1%). Anteroposterior 3D-CRT was compared with a multiarc optimized VMAT solution. Lung, breast, and thyroid cancer risks were estimated by calculating a lifetime attributable risk (LAR), with a LAR ratio (LAR{sub VMAT}-to-LAR{sub 3D-CRT}) as a comparative measure. Cardiac toxicity risks were estimated by calculating absolute excess risk (AER). Results: The LAR ratio favored 3D-CRT for lung cancer induction risk in mediastinal alone (P=.004) and mediastinal plus unilateral neck (P=.02) presentations. LAR ratio for breast cancer was lower for VMAT in mediastinal plus bilateral neck presentations (P=.02), without differences for other sites. For thyroid cancer, no significant differences were observed, regardless of anatomical presentation. A significantly lower AER of cardiac (P=.038) and valvular diseases (P<.0001) was observed for VMAT regardless of disease extent. Conclusions: In a cohort of patients with favorable characteristics in terms of disease extent at diagnosis (large prevalence of nonbulky presentations without axillary involvement), optimized VMAT reduced heart disease risk with comparable risks of thyroid and breast cancer, with an increase in lung cancer induction probability. The results are however strongly influenced by

  12. Direct comparisons of 2D and 3D dental microwear proxies in extant herbivorous and carnivorous mammals.

    DeSantis, Larisa R G; Scott, Jessica R; Schubert, Blaine W; Donohue, Shelly L; McCray, Brian M; Van Stolk, Courtney A; Winburn, Amanda A; Greshko, Michael A; O'Hara, Mackie C


    The analysis of dental microwear is commonly used by paleontologists and anthropologists to clarify the diets of extinct species, including herbivorous and carnivorous mammals. Currently, there are numerous methods employed to quantify dental microwear, varying in the types of microscopes used, magnifications, and the characterization of wear in both two dimensions and three dimensions. Results from dental microwear studies utilizing different methods are not directly comparable and human quantification of wear features (e.g., pits and scratches) introduces interobserver error, with higher error being produced by less experienced individuals. Dental microwear texture analysis (DMTA), which analyzes microwear features in three dimensions, alleviates some of the problems surrounding two-dimensional microwear methods by reducing observer bias. Here, we assess the accuracy and comparability within and between 2D and 3D dental microwear analyses in herbivorous and carnivorous mammals at the same magnification. Specifically, we compare observer-generated 2D microwear data from photosimulations of the identical scanned areas of DMTA in extant African bovids and carnivorans using a scanning white light confocal microscope at 100x magnification. Using this magnification, dental microwear features quantified in 2D were able to separate grazing and frugivorous bovids using scratch frequency; however, DMTA variables were better able to discriminate between disparate dietary niches in both carnivorous and herbivorous mammals. Further, results demonstrate significant interobserver differences in 2D microwear data, with the microwear index remaining the least variable between experienced observers, consistent with prior research. Overall, our results highlight the importance of reducing observer error and analyzing dental microwear in three dimensions in order to consistently interpret diets accurately.

  13. Direct comparisons of 2D and 3D dental microwear proxies in extant herbivorous and carnivorous mammals.

    Larisa R G DeSantis

    Full Text Available The analysis of dental microwear is commonly used by paleontologists and anthropologists to clarify the diets of extinct species, including herbivorous and carnivorous mammals. Currently, there are numerous methods employed to quantify dental microwear, varying in the types of microscopes used, magnifications, and the characterization of wear in both two dimensions and three dimensions. Results from dental microwear studies utilizing different methods are not directly comparable and human quantification of wear features (e.g., pits and scratches introduces interobserver error, with higher error being produced by less experienced individuals. Dental microwear texture analysis (DMTA, which analyzes microwear features in three dimensions, alleviates some of the problems surrounding two-dimensional microwear methods by reducing observer bias. Here, we assess the accuracy and comparability within and between 2D and 3D dental microwear analyses in herbivorous and carnivorous mammals at the same magnification. Specifically, we compare observer-generated 2D microwear data from photosimulations of the identical scanned areas of DMTA in extant African bovids and carnivorans using a scanning white light confocal microscope at 100x magnification. Using this magnification, dental microwear features quantified in 2D were able to separate grazing and frugivorous bovids using scratch frequency; however, DMTA variables were better able to discriminate between disparate dietary niches in both carnivorous and herbivorous mammals. Further, results demonstrate significant interobserver differences in 2D microwear data, with the microwear index remaining the least variable between experienced observers, consistent with prior research. Overall, our results highlight the importance of reducing observer error and analyzing dental microwear in three dimensions in order to consistently interpret diets accurately.

  14. Size-based emphysema cluster analysis on low attenuation area in 3D volumetric CT: comparison with pulmonary functional test

    Lee, Minho; Kim, Namkug; Lee, Sang Min; Seo, Joon Beom; Oh, Sang Young


    To quantify low attenuation area (LAA) of emphysematous regions according to cluster size in 3D volumetric CT data of chronic obstructive pulmonary disease (COPD) patients and to compare these indices with their pulmonary functional test (PFT). Sixty patients with COPD were scanned by a more than 16-multi detector row CT scanner (Siemens Sensation 16 and 64) within 0.75mm collimation. Based on these LAA masks, a length scale analysis to estimate each emphysema LAA's size was performed as follows. At first, Gaussian low pass filter from 30mm to 1mm kernel size with 1mm interval on the mask was performed from large to small size, iteratively. Centroid voxels resistant to the each filter were selected and dilated by the size of the kernel, which was regarded as the specific size emphysema mask. The slopes of area and number of size based LAA (slope of semi-log plot) were analyzed and compared with PFT. PFT parameters including DLco, FEV1, and FEV1/FVC were significantly (all p-value< 0.002) correlated with the slopes (r-values; -0.73, 0.54, 0.69, respectively) and EI (r-values; -0.84, -0.60, -0.68, respectively). In addition, the D independently contributed regression for FEV1 and FEV1/FVC (adjust R sq. of regression study: EI only, 0.70, 0.45; EI and D, 0.71, 0.51, respectively). By the size based LAA segmentation and analysis, we evaluated the Ds of area, number, and distribution of size based LAA, which would be independent factors for predictor of PFT parameters.

  15. Different IMRT solutions vs. 3D-Conformal Radiotherapy in early stage Hodgkin’s lymphoma: dosimetric comparison and clinical considerations

    Fiandra Christian


    Full Text Available Abstract Background Radiotherapy in Hodgkin’s Lymphoma (HL is currently evolving with new attempts to further reduce radiation volumes to the involved-node concept (Involved Nodes Radiation Therapy, INRT and with the use of intensity modulated radiotherapy (IMRT. Currently, IMRT can be planned and delivered with several techniques, and its role is not completely clear. We designed a planning study on a typical dataset drawn from clinical routine with the aim of comparing different IMRT solutions in terms of plan quality and treatment delivery efficiency. Methods A total of 10 young female patients affected with early stage mediastinal HL and treated with 30 Gy INRT after ABVD-based chemotherapy were selected from our database. Five different treatment techniques were compared: 3D-CRT, VMAT (single arc, B-VMAT (“butterfly”, multiple arcs, Helical Tomotherapy (HT and Tomodirect (TD. Beam energy was 6 MV, and all IMRT planning solutions were optimized by inverse planning with specific dose-volume constraints on OAR (breasts, lungs, thyroid gland, coronary ostia, heart. Dose-Volume Histograms (DVHs and Conformity Number (CN were calculated and then compared, both for target and OAR by a statistical analysis (Wilcoxon’s Test. Results PTV coverage was reached for all plans (V95% ≥ 95%; highest mean CN were obtained with HT (0.77 and VMAT (0.76. B-VMAT showed intermediate CN mean values (0.67, while the lowest CN were obtained with TD (0.30 and 3D-CRT techniques (0.30. A trend of inverse correlation between higher CN and larger healthy tissues volumes receiving low radiation doses was shown for lungs and breasts. For thyroid gland and heart/coronary ostia, HT, VMAT and B-VMAT techniques allowed a better sparing in terms of both Dmean and volumes receiving intermediate-high doses compared to 3D-CRT and TD. Conclusions IMRT techniques showed superior target coverage and OAR sparing, with, as an expected consequence, larger volumes of healthy


    S. Devaraju


    Full Text Available Intrusion Detection Systems are challenging task for finding the user as normal user or attack user in any organizational information systems or IT Industry. The Intrusion Detection System is an effective method to deal with the kinds of problem in networks. Different classifiers are used to detect the different kinds of attacks in networks. In this paper, the performance of intrusion detection is compared with various neural network classifiers. In the proposed research the four types of classifiers used are Feed Forward Neural Network (FFNN, Generalized Regression Neural Network (GRNN, Probabilistic Neural Network (PNN and Radial Basis Neural Network (RBNN. The performance of the full featured KDD Cup 1999 dataset is compared with that of the reduced featured KDD Cup 1999 dataset. The MATLAB software is used to train and test the dataset and the efficiency and False Alarm Rate is measured. It is proved that the reduced dataset is performing better than the full featured dataset.

  17. 3D simulation of near-fault strong ground motion:comparison between surface rupture fault and buried fault

    Liu Qifang; Yuan Yifan; Jin Xing


    In this paper,near-fault strong ground motions caused by a surface rupture fault(SRF)and a buried fault(BF) are numerically simulated and compared by using a time-space-decoupled,explicit finite element method combined with a multi-transmitting formula(MTF) of an artificial boundary.Prior to the comparison,verification of the explicit element method and the MTF is conducted.The comparison results show that the final dislocation of the SRF is larger than the BF for the same stress drop on the fault plane.The maximum final dislocation occurs on the fault upper line for the SRF;however,for the BF,the maximum final dislocation is located on the fault central part.Meanwhile,the PGA,PGV and PGD of long period ground motions(≤1 Hz)generated by the SRF are much higher than those of the BF in the near-fault region.The peak value of the velocity pulse generated by the SRF is also higher than the BF.Furthermore,it is found that in a very narrow region along the fault trace,ground motions caused by the SRF are much higher than by the BF.These results may explain why SRFs almost always cause heavy damage in near-fault regions compared to buried faults.

  18. 2D/3D图像配准中的相似性测度和优化算法%Comparison of similarity measurement and optimization methods in 2 D/3 D image registration

    张冉; 王雷; 夏威; 高欣


    在手术引导治疗中,2D/3D图像配准能辅助医生准确定位病人病灶,而准确的配准涉及相似性测度和优化算法等众多方面。为了研究相似性测度和优化算法对2D/3D图像刚性配准的影响,本文结合6种相似性测度和4种优化方法在配准“金标准”数据上进行了2D/3D图像配准实验,并从配准成功率、平均迭代次数和平均配准时间三个方面对配准结果进行了对比研究。实验结果表明,以模式强度为相似性测度,用Powell方法进行优化搜索是最佳配准组合。并且,在不改变相似性测度条件下,Powell方法是所用优化方法中配准效果最好的优化方法。%In surgical guide treatment,2D/3D medical image registration can provide the precise position of patient for surgeon.Accurate registration involves many aspects,such as similarity measurements and optimization methods.In or-der to investigate the influence of similarity measurements and optimization methods on 2D/3D image registration,a comparison of six similarity measurements in combination with four optimization methods is performed using the public and available porcine skull phantom datasets from Medical University Vienna.Comparison is performed for the regis-tration results based on success rate,the number of iterations and execution time.The results show that the most accu-racy registration is obtained by pattern intensity combined with Powell.Furthermore,the best 2D/3D registration re-sults are obtained by Powell search strategy with fixed similarity measurement.

  19. Simulation of platelet, thrombus and erythrocyte hydrodynamic interactions in a 3D arteriole with in vivo comparison.

    Weiwei Wang

    Full Text Available Cylindrical blood vessels, ellipsoid platelets and biconcave-shaped deformable erythrocytes (RBCs are important participants in hemostasis and thrombosis. However, due to the challenge of combining these components in simulation tools, few simulation studies have included all of them in realistic three-dimensional models. In the present study, we apply a recently developed simulation model to incorporate these components and analyze the flow in a thrombotic tubular arteriole, particularly the detailed hydrodynamic interactions between the thrombus shape, RBCs and platelets. It was found that at certain azimuth positions, the velocity drops in the proximity of both the upstream and downstream edge of the thrombus, which is accompanied by a rapid velocity increase in the narrowed region. The RBCs alter the flow profiles significantly from the typical low Reynolds (Re number flow, and also enhance the deposition of free flowing platelets onto the thrombus. By evaluating the platelet-thrombus interaction and platelet-RBC interaction together, several mechanisms of platelet deposition augmentation are identified. With in vivo data comparison, our model illustrates the potential of future thrombosis studies that incorporate detailed receptor-ligand adhesion modules.

  20. Comparison of 3D Maximum A Posteriori and Filtered Backprojection algorithms for high resolution animal imaging in microPET

    Chatziioannou, A.; Qi, J.; Moore, A.; Annala, A.; Nguyen, K.; Leahy, R.M.; Cherry, S.R.


    We have evaluated the performance of two three dimensional reconstruction algorithms with data acquired from microPET, a high resolution tomograph dedicated to small animal imaging. The first was a linear filtered-backprojection algorithm (FBP) with reprojection of the missing data and the second was a statistical maximum-aposteriori probability algorithm (MAP). The two algorithms were evaluated in terms of their resolution performance, both in phantoms and in vivo. Sixty independent realizations of a phantom simulating the brain of a baby monkey were acquired, each containing 3 million counts. Each of these realizations was reconstructed independently with both algorithms. The ensemble of the sixty reconstructed realizations was used to estimate the standard deviation as a measure of the noise for each reconstruction algorithm. More detail was recovered in the MAP reconstruction without an increase in noise relative to FBP. Studies in a simple cylindrical compartment phantom demonstrated improved recovery of known activity ratios with MAP. Finally in vivo studies also demonstrated a clear improvement in spatial resolution using the MAP algorithm. The quantitative accuracy of the MAP reconstruction was also evaluated by comparison with autoradiography and direct well counting of tissue samples and was shown to be superior.

  1. In vitro comparison of Doppler and catheter-measured pressure gradients in 3D models of mitral valve calcification.

    Herrmann, Tarrah A; Siefert, Andrew W; Pressman, Gregg S; Gollin, Hannah R; Touchton, Steven A; Saikrishnan, Neelakantan; Yoganathan, Ajit P


    Mitral annular calcification (MAC) involves calcium deposition in the fibrous annulus supporting the mitral valve (MV). When calcification extends onto the leaflets, valve opening can be restricted. The influence of MAC MV geometry on Doppler gradients is unknown. This study describes a novel methodology to rapid-prototype subject-specific MAC MVs. Replicated valves were used to assess the effects of distorted annular-leaflet geometry on Doppler-derived, transmitral gradients in comparison to direct pressure measurements and to determine if transmitral gradients vary according to measurement location. Three-dimensional echocardiography data sets were selected for two MAC MVs and one healthy MV. These MVs were segmented and rapid prototyped in their middiastolic configuration for in vitro testing. The effects of MV geometry, measurement modality, and measurement location on transmitral pressure gradient were assessed by Doppler and catheter at three locations along the MV's intercommissural axis. When comparing dimensions of the rapid-prototyped valves to the subject echocardiography data sets, mean relative errors ranged from 6.2% to 35%. For the evaluated MVs, Doppler pressure gradients exhibited good agreement with catheter-measured gradients at a variety of flow rates, though with slight systematic overestimation in the recreated MAC valves. For all of the tested MVs, measuring the transmitral pressure gradient at differing valve orifice positions had minimal impact on observed gradients. Upon the testing of additional normal and calcific MVs, these data may contribute to an improved clinical understanding of MAC-related mitral stenosis. Moreover, they provide the ability to statistically evaluate between measurement locations, flow rates, and valve geometries for Doppler-derived pressure gradients. Determining these end points will contribute to greater clinical understanding for the diagnosis MAC patients and understanding the use and application of Doppler

  2. A new protein binding pocket similarity measure based on comparison of clouds of atoms in 3D: application to ligand prediction

    Zaslavskiy Mikhail


    Full Text Available Abstract Background Predicting which molecules can bind to a given binding site of a protein with known 3D structure is important to decipher the protein function, and useful in drug design. A classical assumption in structural biology is that proteins with similar 3D structures have related molecular functions, and therefore may bind similar ligands. However, proteins that do not display any overall sequence or structure similarity may also bind similar ligands if they contain similar binding sites. Quantitatively assessing the similarity between binding sites may therefore be useful to propose new ligands for a given pocket, based on those known for similar pockets. Results We propose a new method to quantify the similarity between binding pockets, and explore its relevance for ligand prediction. We represent each pocket by a cloud of atoms, and assess the similarity between two pockets by aligning their atoms in the 3D space and comparing the resulting configurations with a convolution kernel. Pocket alignment and comparison is possible even when the corresponding proteins share no sequence or overall structure similarities. In order to predict ligands for a given target pocket, we compare it to an ensemble of pockets with known ligands to identify the most similar pockets. We discuss two criteria to evaluate the performance of a binding pocket similarity measure in the context of ligand prediction, namely, area under ROC curve (AUC scores and classification based scores. We show that the latter is better suited to evaluate the methods with respect to ligand prediction, and demonstrate the relevance of our new binding site similarity compared to existing similarity measures. Conclusions This study demonstrates the relevance of the proposed method to identify ligands binding to known binding pockets. We also provide a new benchmark for future work in this field. The new method and the benchmark are available at

  3. A fractal approach to the dark silicon problem: A comparison of 3D computer architectures - Standard slices versus fractal Menger sponge geometry

    Herrmann, Richard


    The dark silicon problem, which limits the power-growth of future computer generations, is interpreted as a heat energy transport problem when increasing the energy emitting surface area within a given volume. A comparison of two 3D-configuration models, namely a standard slicing and a fractal surface generation within the Menger sponge geometry is presented. It is shown, that for iteration orders $n>3$ the fractal model shows increasingly better thermal behavior. As a consequence cooling problems may be minimized by using a fractal architecture. Therefore the Menger sponge geometry is a good example for fractal architectures applicable not only in computer science, but also e.g. in chemistry when building chemical reactors, optimizing catalytic processes or in sensor construction technology building highly effective sensors for toxic gases or water analysis.

  4. Exact monitoring of aortic diameters in Marfan patients without gadolinium contrast: intraindividual comparison of 2D SSFP imaging with 3D CE-MRA and echocardiography

    Veldhoen, Simon [University Medical Center Wuerzburg, Department of Diagnostic and Interventional Radiology, Bavaria (Germany); University Medical Center Hamburg-Eppendorf, Department of Diagnostic and Interventional Radiology, Hamburg (Germany); Behzadi, Cyrus; Derlin, Thorsten; Henes, Frank Oliver; Adam, Gerhard; Bannas, Peter [University Medical Center Hamburg-Eppendorf, Department of Diagnostic and Interventional Radiology, Hamburg (Germany); Rybczinsky, Meike; Kodolitsch, Yskert von; Sheikhzadeh, Sara [University Medical Center Hamburg-Eppendorf, Department of General and Interventional Cardiology, Hamburg (Germany); Bley, Thorsten Alexander [University Medical Center Wuerzburg, Department of Diagnostic and Interventional Radiology, Bavaria (Germany)


    To assess whether ECG-gated non-contrast 2D steady-state free precession (SSFP) imaging allows for exact monitoring of aortic diameters in Marfan syndrome (MFS) patients using non-ECG-gated contrast-enhanced 3D magnetic resonance angiography (CE-MRA) and echocardiography for intraindividual comparison. Non-ECG-gated CE-MRA and ECG-gated non-contrast SSFP at 1.5 T were prospectively performed in 50 patients. Two readers measured aortic diameters on para-sagittal images identically aligned with the aortic arch at the sinuses of Valsalva, sinotubular junction, ascending/descending aorta and aortic arch. Image quality was assessed on a three-point scale. Aortic root diameters acquired by echocardiography were used as reference. Intra- and interobserver variances were smaller for SSFP at the sinuses of Valsalva (p = 0.002; p = 0.002) and sinotubular junction (p = 0.014; p = 0.043). Image quality was better in SSFP than in CE-MRA at the sinuses of Valsalva (p < 0.0001), sinotubular junction (p < 0.0001) and ascending aorta (p = 0.02). CE-MRA yielded higher diameters than SSFP at the sinuses of Valsalva (mean bias, 2.5 mm; p < 0.0001), and comparison with echocardiography confirmed a higher bias for CE-MRA (7.2 ± 3.4 mm vs. SSFP, 4.7 ± 2.6 mm). ECG-gated non-contrast 2D SSFP imaging provides superior image quality with higher validity compared to non-ECG-gated contrast-enhanced 3D imaging. Since CE-MRA requires contrast agents with potential adverse effects, non-contrast SSFP imaging is an appropriate alternative for exact and riskless aortic monitoring of MFS patients. (orig.)

  5. Intensity-modulated proton therapy, volumetric-modulated arc therapy, and 3D conformal radiotherapy in anaplastic astrocytoma and glioblastoma. A dosimetric comparison

    Adeberg, S.; Debus, J. [Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg (Germany); Heidelberg Ion-Beam Therapy Center (HIT), Heidelberg (Germany); University Hospital Heidelberg, Department of Radiation Oncology, Heidelberg (Germany); German Cancer Research Center (DKFZ), Clinical Cooperation Unit Radiation Oncology, Heidelberg (Germany); Harrabi, S.B.; Bougatf, N.; Rieber, J.; Koerber, S.A.; Herfarth, K.; Rieken, S. [Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg (Germany); Heidelberg Ion-Beam Therapy Center (HIT), Heidelberg (Germany); University Hospital Heidelberg, Department of Radiation Oncology, Heidelberg (Germany); Bernhardt, D.; Syed, M.; Sprave, T.; Mohr, A. [Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg (Germany); University Hospital Heidelberg, Department of Radiation Oncology, Heidelberg (Germany); Abdollahi, A. [University Hospital Heidelberg, Department of Radiation Oncology, Heidelberg (Germany); Haberer, T. [Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg (Germany); Heidelberg Ion-Beam Therapy Center (HIT), Heidelberg (Germany); Combs, S.E. [Technische Universitaet Muenchen, Department of Radiation Oncology, Muenchen (Germany); Helmholtz Zentrum Muenchen, Institut fuer Innovative Radiotherapie (iRT), Department of Radiation Sciences (DRS), Neuherberg (Germany)


    The prognosis for high-grade glioma (HGG) patients is poor; thus, treatment-related side effects need to be minimized to conserve quality of life and functionality. Advanced techniques such as proton radiation therapy (PRT) and volumetric-modulated arc therapy (VMAT) may potentially further reduce the frequency and severity of radiogenic impairment. We retrospectively assessed 12 HGG patients who had undergone postoperative intensity-modulated proton therapy (IMPT). VMAT and 3D conformal radiotherapy (3D-CRT) plans were generated and optimized for comparison after contouring crucial neuronal structures important for neurogenesis and neurocognitive function. Integral dose (ID), homogeneity index (HI), and inhomogeneity coefficient (IC) were calculated from dose statistics. Toxicity data were evaluated. Target volume coverage was comparable for all three modalities. Compared to 3D-CRT and VMAT, PRT showed statistically significant reductions (p < 0.05) in mean dose to whole brain (-20.2 %, -22.7 %); supratentorial (-14.2 %, -20,8 %) and infratentorial (-91.0 %, -77.0 %) regions; brainstem (-67.6 %, -28.1 %); pituitary gland (-52.9 %, -52.5 %); contralateral hippocampus (-98.9 %, -98.7 %); and contralateral subventricular zone (-62.7 %, -66.7 %, respectively). Fatigue (91.7 %), radiation dermatitis (75.0 %), focal alopecia (100.0 %), nausea (41.7 %), cephalgia (58.3 %), and transient cerebral edema (16.7 %) were the most common acute toxicities. Essential dose reduction while maintaining equal target volume coverage was observed using PRT, particularly in contralaterally located critical neuronal structures, areas of neurogenesis, and structures of neurocognitive functions. These findings were supported by preliminary clinical results confirming the safety and feasibility of PRT in HGG. (orig.) [German] Die Prognose bei ''High-grade''-Gliomen (HGG) ist infaust. Gerade bei diesen Patienten sollten therapieassoziierte Nebenwirkungen minimiert werden

  6. Evaluation of Methods for Comparison of Spatiotemporal and Time Series Datasets

    Getman, Dan [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Bush, Brian [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Inman, Danny [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Elmore, Ryan [National Renewable Energy Laboratory (NREL), Golden, CO (United States)


    Data used by the National Renewable Energy Laboratory (NREL) in energy analysis are often produced by industry and licensed or purchased for analysis. While this practice provides needed flexibility in selecting data for analysis it presents challenges in understanding the differences among multiple, ostensibly similar, datasets. As options for source data become more varied, it is important to be able to articulate why certain datasets were chosen and to ensure those include the data that best meet the boundaries and/or limitations of a particular analysis. This report represents the first of three phases of research intended to develop methods to quantitatively assess and compare both input datasets and the results of analyses performed at NREL. This capability is critical to identifying tipping points in the costs or benefits of achieving high spatial and temporal resolution of input data.


    Brdnik, Lovro


    Diplomsko delo analizira trenutno stanje 3D tiskalnikov na trgu. Prikazan je razvoj in principi delovanja 3D tiskalnikov. Predstavljeni so tipi 3D tiskalnikov, njihove prednosti in slabosti. Podrobneje je predstavljena zgradba in delovanje koračnih motorjev. Opravljene so meritve koračnih motorjev. Opisana je programska oprema za rokovanje s 3D tiskalniki in komponente, ki jih potrebujemo za izdelavo. Diploma se oklepa vprašanja, ali je izdelava 3D tiskalnika bolj ekonomična kot pa naložba v ...

  8. Precipitation comparison for the CFSR, MERRA, TRMM3B42 and Combined Scheme datasets in Bolivia

    Blacutt, Luis A.; Herdies, Dirceu L.; de Gonçalves, Luis Gustavo G.; Vila, Daniel A.; Andrade, Marcos


    An overwhelming number of applications depend on reliable precipitation estimations. However, over complex terrain in regions such as the Andes or the southwestern Amazon, the spatial coverage of rain gauges is scarce. Two reanalysis datasets, a satellite algorithm and a scheme that combines surface observations with satellite estimations were selected for studying rainfall in the following areas of Bolivia: the central Andes, Altiplano, southwestern Amazonia, and Chaco. These Bolivian regions can be divided into three main basins: the Altiplano, La Plata, and Amazon. The selected reanalyses were the Modern-Era Retrospective Analysis for Research and Applications, which has a horizontal resolution (~ 50 km) conducive for studying rainfall in relatively small precipitation systems, and the Climate Forecast System Reanalysis and Reforecast, which features an improved horizontal resolution (~ 38 km). The third dataset was the seventh version of the Tropical Rainfall Measurement Mission 3B42 algorithm, which is conducive for studying rainfall at an ~ 25 km horizontal resolution. The fourth dataset utilizes a new technique known as the Combined Scheme, which successfully removes satellite bias. All four of these datasets were aggregated to a coarser resolution. Additionally, the daily totals were calculated to match the cumulative daily values of the ground observations. This research aimed to describe and compare precipitations in the two reanalysis datasets, the satellite-algorithm dataset, and the Combined Scheme with ground observations. Two seasons were selected for studying the precipitation estimates: the rainy season (December-February) and the dry season (June-August). The average, bias, standard deviation, correlation coefficient, and root mean square error were calculated. Moreover, a contingency table was generated to calculate the accuracy, bias frequency, probability of detection, false alarm ratio, and equitable threat score. All four datasets correctly

  9. Inter-comparison of stratospheric mean-meridional circulation and eddy mixing among six reanalysis datasets

    K. Miyazaki


    Full Text Available The stratospheric mean-meridional circulation (MMC and eddy mixing are compared among six meteorological reanalysis datasets: NCEP-NCAR, NCEP-CFSR, ERA-40, ERA-Interim, JRA-25, and JRA-55 for the period 1979–2012. The reanalysis datasets produced using advanced systems (i.e., NCEP-CFSR, ERA-Interim, and JRA-55 generally reveal a weaker MMC and stronger eddy mixing in the Northern Hemisphere (NH compared with those produced using older systems (i.e., NCEP/NCAR, ERA-40, and JRA-25. In the NH lower stratosphere, the stronger eddy mixing is attributed to stronger planetary-scale mixing in the new datasets, whereas small-scale mixing is weaker in the new datasets. Conventional data assimilation techniques introduce analysis increments without maintaining physical balance, which may have caused an overly strong MMC and spurious small-scale eddies in the old datasets. At the NH mid-latitudes, only ERA-Interim reveals a weakening MMC trend in the deep branch of the Brewer–Dobson Circulation (BDC. The relative importance of the eddy mixing compared with the mean transport in the subtropical lower stratosphere is considered to be important in controlling mean Age-of-Air (AoA variations above, which showed increasing trends in ERA-Interim and JRA-55; this together with the weakened MMC in the deep branch may imply an increasing AoA trend in the NH middle stratosphere in ERA-Interim. Overall, discrepancies between the different variables and trends therein as derived from the different reanalyses are still relatively large, suggesting that more investments into these products are needed in order to obtain a consolidated picture of observed changes in the BDC and the mechanisms that drive them.

  10. Clinical implication of parameteroptimized 3D-FISP MR angiography (MRA) in children with aortic coarctation: comparison with catheter angiography; Stellenwert einer parameteroptimierten 3D-FISP-MR-Angiographie bei Kindern mit Aortenisthmusstenose im Vergleich zur Katheterangiographie

    Kramer, U.; Dammann, F.; Miller, S.; Fenchel, M.; Claussen, C.D. [Universitaet Tuebingen (Germany). Abteilung Radiologische Diagnostik; Greil, G.; Sieverding, L. [Universitaet Tuebingen (Germany). Abteilung Kinderkardiologie; Schick, F. [Universitaet Tuebingen (Germany). Sektion Experimentelle Radiologie


    Purpose: To implement parameter-optimized 3D-FISP MR angiography (MRA) with interleaved double-slab excitation and to compare the result with catheter angiography in children with aortic coarctation. Materials and Methods: Eighteen children aged 2-15 years (mean 9.1 years) underwent MR imaging on a 1.5 T body scanner (Magnetom Vision, Siemens, Germany). All patients had undergone correlative catheter angiography. T1-weighted turbo spin echo (TSE) images (TR 600 ms, TE 17 ms, flip 160 , slice thickness 2-4 mm) were obtained in axial and parasagittal orientation, followed by an optimized 3D-FISP MR angiography in a sagittal plane (TR 12.5 ms, TE 5.5 ms, flip 22 , matrix 256 x 256, slice thickness 1.25 mm). All children were sedated but on spontaneous breathing. Image quality was graded by two experienced reviewers using a 4-point scoring system. Source images and reformatted maximum intensity projections (MIP) were analyzed for blood-tissue contrast as well as size and focal stenoses of the aortic arch. Results: Aortic coarctation was found in 13 of 18 patients, using the 3D-FISP MRA. A high correlation value (r=0.96) was found compared to catheter angiography. Image quality was high in 94% with well defined blood-tissue contrast in all cases. The sensitivity of flow and breathing motion was low. Examination time was about 15 minutes depending on volume of interest and heart rate. Diagnostic accuracy has shown improvement using a combined analysis of source and MIP images. The mentioned technique has provided an excellent display of thoracic vasculature. (orig.)

  11. A comparison of the performance of the 3-D super-ensemble and an ensemble Kalman filter for short-range regional ocean prediction

    Baptiste Mourre


    Full Text Available This study compares the ability of two approaches integrating models and data to forecast the Ligurian Sea regional oceanographic conditions in the short-term range (0–72 hours when constrained by a common observation dataset. The post-processing 3-D super-ensemble (3DSE algorithm, which uses observations to optimally combine multi-model forecasts into a single prediction of the oceanic variable, is first considered. The 3DSE predictive skills are compared to those of the Regional Ocean Modeling System model in which observations are assimilated through a more conventional ensemble Kalman filter (EnKF approach. Assimilated measurements include sea surface temperature maps, and temperature and salinity subsurface observations from a fleet of five underwater gliders. Retrospective analyses are carried out to produce daily predictions during the 11-d period of the REP10 sea trial experiment. The forecast skill evaluation based on a distributed multi-sensor validation dataset indicates an overall superior performance of the EnKF, both at the surface and at depth. While the 3DSE and EnKF perform comparably well in the area spanned by the incorporated measurements, the 3DSE accuracy is found to rapidly decrease outside this area. In particular, the univariate formulation of the method combined with the absence of regular surface salinity measurements produces large errors in the 3DSE salinity forecast. On the contrary, the EnKF leads to more homogeneous forecast errors over the modelling domain for both temperature and salinity. The EnKF is found to consistently improve the predictions with respect to the control solution without assimilation and to be positively skilled when compared to the climatological estimate. For typical regional oceanographic applications with scarce subsurface observations, the lack of physical spatial and multivariate error covariances applicable to the individual model weights in the 3DSE formulation constitutes a major

  12. Comparison of 2D temperature maps recorded during laser-induced thermal tissue treatment with corresponding temperature distributions calculated from 3D Monte-Carlo simulations

    Busse, Harald; Bublat, Martin; Ratering, Ralf; Rassek, Margarethe; Schwarzmaier, Hans-Joachim; Kahn, Thomas


    Minimally invasive techniques often require special biomedical monitoring schemes. In the case of laser coagulation of tumors accurate temperature mapping is desirable for therapy control. While magnetic resonance (MR)-based thermometry can easily yield qualitative results it is still difficult to calibrate this technique with independent temperature probes for the entire 2D field of view. Calculated temperature maps derived from Monte-Carlo simulations (MCS), on the other hand, are suitable for therapy planning and dosimetry but typically can not account for the extract individual tissue parameters and physiological changes upon heating. In this work, online thermometry was combined with MCS techniques to explore the feasibility and potential of such a biomodal approach for surgical assist systems. For the first time, the result of a 3D simulation were evaluated with MR techniques. An MR thermometry system was used to monitor the temperature evolution during laser-induced thermal treatment of bovine liver using a commercially available water-cooled applicator. A systematic comparison between MR-derived 2D temperature maps in different orientations and corresponding snapshots of a 3D MCS of the laser-induced processes is presented. The MCS is capable of resolving the complex temperature patterns observed in the MR-derived images and yields a good agreement with respect to absolute temperatures and damage volume dimensions. The observed quantitative agreement is around 10 degrees C and on the order of 10 percent, respectively. The integrated simulation-and-monitoring approach has the potential to improve surgical assistance during thermal interventions.

  13. Comparison of Radiation Treatment Plans for Breast Cancer between 3D Conformal in Prone and Supine Positions in Contrast to VMAT and IMRT Supine Positions

    Bejarano Buele, Ana Isabel

    The treatment regimen for breast cancer patients typically involves Whole Breast Irradiation (WBI). The coverage and extent of the radiation treatment is dictated by location of tumor mass, breast tissue distribution, involvement of lymph nodes, and other factors. The current standard treatment approach used at our institution is a 3D tangential beam geometry, which involves two fields irradiating the breast, or a four field beam arrangement covering the whole breast and involved nodes, while decreasing the dose to organs as risk (OARs) such as the lung and heart. The coverage of these targets can be difficult to achieve in patients with unfavorable thoracic geometries, especially in those cases in which the planning target volume (PTV) is extended to the chest wall. It is a well-known fact that exposure of the heart to ionizing radiation has been proved to increase the subsequent rate of ischemic heart disease. In these cases, inverse planned treatments have become a proven alternative to the 3D approach. The goal of this research project is to evaluate the factors that affect our current techniques as well as to adapt the development of inverse modulated techniques for our clinic, in which breast cancer patients are one of the largest populations treated. For this purpose, a dosimetric comparison along with the evaluation of immobilization devices was necessary. Radiation treatment plans were designed and dosimetrically compared for 5 patients in both, supine and prone positions. For 8 patients, VMAT and IMRT plans were created and evaluated in the supine position. Skin flash incorporation for inverse modulated plans required measurement of the surface dose as well as an evaluation of breast volume changes during a treatment course. It was found that prone 3D conformal plans as well as the VMAT and IMRT plans are generally superior in sparing OARs to supine plans with comparable PTV coverage. Prone setup leads to larger shifts in breast volume as well as in

  14. 3D and Education

    Meulien Ohlmann, Odile


    Today the industry offers a chain of 3D products. Learning to "read" and to "create in 3D" becomes an issue of education of primary importance. 25 years professional experience in France, the United States and Germany, Odile Meulien set up a personal method of initiation to 3D creation that entails the spatial/temporal experience of the holographic visual. She will present some different tools and techniques used for this learning, their advantages and disadvantages, programs and issues of educational policies, constraints and expectations related to the development of new techniques for 3D imaging. Although the creation of display holograms is very much reduced compared to the creation of the 90ies, the holographic concept is spreading in all scientific, social, and artistic activities of our present time. She will also raise many questions: What means 3D? Is it communication? Is it perception? How the seeing and none seeing is interferes? What else has to be taken in consideration to communicate in 3D? How to handle the non visible relations of moving objects with subjects? Does this transform our model of exchange with others? What kind of interaction this has with our everyday life? Then come more practical questions: How to learn creating 3D visualization, to learn 3D grammar, 3D language, 3D thinking? What for? At what level? In which matter? for whom?

  15. A comparison of HYSPLIT backward trajectories generated from two GDAS datasets.

    Su, Lin; Yuan, Zibing; Fung, Jimmy C H; Lau, Alexis K H


    The Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model is widely used to generate backward trajectories in given starting locations. However, differences exist between trajectories generated from the model with different input datasets. In this study, backward trajectories in Hong Kong in the entire year of 2011 are derived by HYSPLIT model. Two sets of Global Data Assimilation System (GDAS) output data associated with different horizontal and vertical resolutions (GDAS1 and GDAS0P5) are used as drivers in an attempt to quantify the differences between the results and discover the underlying reasons responsible for discrepancy. The results reveal that the significant differences between back trajectories generated from the two GDAS datasets can be mainly attributed to different vertical velocity calculation methods due to the absence of vertical velocity in GDAS0P5 dataset. The HYSPLIT trajectories are also sensitive to the horizontal and vertical resolutions of the input meteorological data, but to lesser extents. Results of cluster analysis indicate that when the air mass is from the north, northeast, or west with a long-to-medium range, the HYSPLIT backward trajectories are sensitive to the vertical advection calculation method and data resolution, whereas when the air mass is from the south or southwest with a long range, the trajectories are more likely to remain unchanged with the shifting of vertical velocity or data resolution. By comparing the vertical velocities with the observations and the performance in retrieving PM contributions from different directions, we conclude that GDAS1 dataset is more plausible in backward trajectory analysis in the Pearl River Delta.

  16. The Use of Airborne and Mobile Laser Scanning for Modeling Railway Environments in 3D

    Lingli Zhu


    Full Text Available This paper presents methods for 3D modeling of railway environments from airborne laser scanning (ALS and mobile laser scanning (MLS. Conventionally, aerial data such as ALS and aerial images were utilized for 3D model reconstruction. However, 3D model reconstruction only from aerial-view datasets can not meet the requirement of advanced visualization (e.g., walk-through visualization. In this paper, objects in a railway environment such as the ground, railroads, buildings, high voltage powerlines, pylons and so on were reconstructed and visualized in real-life experiments in Kokemaki, Finland. Because of the complex terrain and scenes in railway environments, 3D modeling is challenging, especially for high resolution walk-through visualizations. However, MLS has flexible platforms and provides the possibility of acquiring data in a complex environment in high detail by combining with ALS data to produce complete 3D scene modeling. A procedure from point cloud classification to 3D reconstruction and 3D visualization is introduced, and new solutions are proposed for object extraction, 3D reconstruction, model simplification and final model 3D visualization. Image processing technology is used for the classification, 3D randomized Hough transformations (RHT are used for the planar detection, and a quadtree approach is used for the ground model simplification. The results are visually analyzed by a comparison with an orthophoto at a 20 cm ground resolution.


    Kolar, Nataša


    Diplomsko delo predstavi razvoj tiskanja skozi čas. Podrobneje so opisani 3D tiskalniki, ki uporabljajo različne tehnologije 3D tiskanja. Predstavljene so različne tehnologije 3D tiskanja, njihova uporaba in narejeni prototipi oz. končni izdelki. Diplomsko delo opiše celoten postopek, od zamisli, priprave podatkov in tiskalnika do izdelave prototipa oz. končnega izdelka.

  18. A dosimetric comparison between 3D-Conformal radiation therapy and intensity modulated radiation therapy plans in the treatment of posterior fossa boost in children with high risk medulloblastom

    Saad El Din I; Abd El AAl H; Makaar W; Mashhour K; El Beih D; Hashem W


    Objective:The work is a comparative study between two modalities of radiation therapy, the aim of which is to compare 3D conformal radiation therapy (3D-CRT) and intensity modulated radiation therapy (IMRT) in treating posterior fossa boost in children with high risk medul oblastoma;dosimetrical y evaluating and comparing both techniques as regard target coverage and doses to organs at risk (OAR). Methods:Twenty patients with high risk medul oblastoma were treated by 3D-CRT technique. A dosimetric comparison was done by performing two plans for the posterior fossa boost, 3D-CRT and IMRT plans, for the same patient using Eclipse planning system (version 8.6). Results:IMRT had a better conformity index compared to 3D-CRT plans (P value of 0.000). As for the dose homogeneity it was also better in the IMRT plans, yet it hasn’t reached the statistical significant value. Also, doses received by the cochleae, brainstem and spinal cord were significantly less in the IMRT plans than those of 3D-CRT (P value<0.05). Conclusion:IMRT technique was clearly able to improve conformity and homogeneity index, spare the cochleae, reduce dose to the brainstem and spinal cord in comparison to 3D-CRT technique.

  19. Design of a head phantom produced on a 3D rapid prototyping printer and comparison with a RANDO and 3M lucite head phantom in eye dosimetry applications.

    Homolka, Peter; Figl, Michael; Wartak, Andreas; Glanzer, Mathias; Dünkelmeyer, Martina; Hojreh, Azadeh; Hummel, Johann


    An anthropomorphic head phantom including eye inserts allowing placement of TLDs 3 mm below the cornea has been produced on a 3D printer using a photo-cured acrylic resin to best allow tissue equivalence. Thus Hp(3) can be determined in radiological and interventional photon radiation fields. Eye doses and doses to the forehead have been compared to an Alderson RANDO head and a 3M Lucite skull phantom in terms of surface dose per incident air kerma for frontal irradiation since the commercial phantoms do not allow placement of TLDs 3 mm below the corneal surface. A comparison of dose reduction factors (DRFs) of a common lead glasses model has also been performed. Eye dose per incident air kerma were comparable between all three phantoms (printed phantom: 1.40, standard error (SE) 0.04; RANDO: 1.36, SE 0.03; 3M: 1.37, SE 0.03). Doses to the forehead were identical to eye surface doses for the printed phantom and the RANDO head (ratio 1.00 SE 0.04, and 0.99 SE 0.03, respectively). In the 3M Lucite skull phantom dose on the forehead was 15% lower than dose to the eyes attributable to phantom properties. DRF of a sport frame style leaded glasses model with 0.75 mm lead equivalence measured were 6.8 SE 0.5, 9.3 SE 0.4 and 10.5 SE 0.5 for the RANDO head, the printed phantom, and the 3M Lucite head phantom, respectively, for frontal irradiation. A comparison of doses measured in 3 mm depth and on the surface of the eyes in the printed phantom revealed no difference larger than standard errors from TLD dosimetry. 3D printing offers an interesting opportunity for phantom design with increasing potential as printers allowing combinations of tissue substitutes will become available. Variations between phantoms may provide a useful indication of uncertainty budgets when using phantom measurements to estimate individual personnel doses.

  20. A comparison of porosity analysis using 2D stereology estimates and 3D serial sectioning for additively manufactured Ti 6Al 2Sn 4Zr 2Mo alloy; Vergleich der Porositaetsanalyse einer Ti 6Al 2Sn 4Zr 2Mo-Legierung aus additiver Fertigung mittels stereologischer Schaetzungen (2D) und mit Serienschnitten (3D)

    Ganti, Satya R.; Velez, Michael A.; Geier, Brian A.; Hayes, Brian J.; Turner, Bryan J.; Jenkins, Elizabeth J. [UES Inc., Dayton, OH (United States)


    Porosity is a typical defect in additively manufactured (AM) parts. Such defects limit the properties and performance of AM parts, and therefore need to be characterized accurately. Current methods for characterization of defects and microstructure rely on classical stereological methods that extrapolate information from two dimensional images. The automation of serial sectioning provides an opportunity to precisely and accurately quantify porosity in three dimensions in materials. In this work, we analyzed the porosity of an additively manufactured Ti 6Al 2Sn 4Zr 2Mo sample using Robo-Met.3D {sup registered}, an automated serial sectioning system. Image processing for three dimensional reconstruction of the serial-sectioned two dimensional images was performed using open source image analysis software (Fiji/ImageJ, Dream.3D, Paraview). The results from this 3D serial sectioning analysis were then compared to classical 2D stereological methods (Saltykov stereological theory). We found that for this dataset, the classical 2D methods underestimated the porosity size and distributions of the larger pores; a critical attribute to fatigue behavior of the AM part. The results suggest that acquiring experimental data with equipment such as Robo-Met.3D {sup registered} to measure the number and size of particles such as pores in a volume irrespective of knowing their shape is a better choice.

  1. User-Appropriate Viewer for High Resolution Interactive Engagement with 3d Digital Cultural Artefacts

    Gillespie, D.; La Pensée, A.; Cooper, M.


    Three dimensional (3D) laser scanning is an important documentation technique for cultural heritage. This technology has been adopted from the engineering and aeronautical industry and is an invaluable tool for the documentation of objects within museum collections (La Pensée, 2008). The datasets created via close range laser scanning are extremely accurate and the created 3D dataset allows for a more detailed analysis in comparison to other documentation technologies such as photography. The dataset can be used for a range of different applications including: documentation; archiving; surface monitoring; replication; gallery interactives; educational sessions; conservation and visualization. However, the novel nature of a 3D dataset is presenting a rather unique challenge with respect to its sharing and dissemination. This is in part due to the need for specialised 3D software and a supported graphics card to display high resolution 3D models. This can be detrimental to one of the main goals of cultural institutions, which is to share knowledge and enable activities such as research, education and entertainment. This has limited the presentation of 3D models of cultural heritage objects to mainly either images or videos. Yet with recent developments in computer graphics, increased internet speed and emerging technologies such as Adobe's Stage 3D (Adobe, 2013) and WebGL (Khronos, 2013), it is now possible to share a dataset directly within a webpage. This allows website visitors to interact with the 3D dataset allowing them to explore every angle of the object, gaining an insight into its shape and nature. This can be very important considering that it is difficult to offer the same level of understanding of the object through the use of traditional mediums such as photographs and videos. Yet this presents a range of problems: this is a very novel experience and very few people have engaged with 3D objects outside of 3D software packages or games. This paper

  2. Detection of tibial condylar fractures using 3D imaging with a mobile image amplifier (Siemens ISO-C-3D): Comparison with plain films and spiral CT; Frakturdiagnostik am Kniegelenk mit einem neuen mobilen CT-System (ISO-C-3D): Vergleich mit konventionellem Roentgen und Spiral-CT

    Kotsianos, D.; Rock, C.; Wirth, S.; Linsenmaier, U.; Brandl, R.; Fischer, T.; Pfeifer, K.J.; Reiser, M. [Klinikum der Universitaet Muenchen-Innenstadt, Muenchen (Germany). Inst. fuer Klinische Radiologie; Euler, E.; Mutschler, W. [Klinikum der Universitaet Muenchen-Innenstadt, Muenchen (Germany). Chirurgische Klinik und Poliklinik


    Purpose: To analyze a prototype mobile C-arm 3D image amplifier in the detection and classification of experimental tibial condylar fractures with multiplanar reconstructions (MPR). Method: Human knee specimens (n=22) with tibial condylar fractures were examined with a prototype C-arm (ISO-C-3D, Siemens AG), plain films (CR) and spiral CT (CT). The motorized C-arm provides fluoroscopic images during a 190 orbital rotation computing a 119 mm data cube. From these 3D data sets MP reconstructions were obtained. All images were evaluated by four independent readers for the detection and assessment of fracture lines. All fractures were classified according to the Mueller AO classification. To confirm the results, the specimens were finally surgically dissected. Results: 97% of the tibial condylar fractures were easily seen and correctly classified according to the Mueller AO classification on MP reconstruction of the ISO-C-3D. There is no significant difference between ISO-C and CT in detection and correct classification of fractures, but ISO-CD-3D is significant by better than CR. (orig.) [German] Zielsetzung: Ziel der vorliegenden Studie war es, die diagnostischen Moeglichkeiten und Grenzen der Erkennbarkeit und Klassifizierung von Frakturen mit multiplanaren Rekonstruktionen (MPR) aus 3D-Datensaetzen eines fahrbaren C-Bogengeraetes an Kniegelenken zu pruefen. Methodik: Kniegelenke von Verstorbenen (n=22) mit Tibiakopffrakturen wurden an einem Prototyp eines mobilen C-Bogen Schnittbild-/Durchleuchtungsgeraets (ISO-C-3D, Siemens AG Erlangen) untersucht. Das Geraet erzeugt waehrend einer einmaligen 190-Grad-Rotation 100 Projektionsaufnahmen, aus denen ein 3D-Volumendatensatz gewonnen wird. Aus diesem werden Hochkontrastschnittbilder als MP-Rekonstruktionen in allen drei Raumebenen errechnet und visualisiert. Die Kniegelenke wurden von 4 unabhaengigen Befundern hinsichtlich Frakturerkennbarkeit, Frakturart und -ausmass unter Verwendung der MP

  3. 3D virtuel udstilling

    Tournay, Bruno; Rüdiger, Bjarne


    3d digital model af Arkitektskolens gård med virtuel udstilling af afgangsprojekter fra afgangen sommer 2006. 10 s.......3d digital model af Arkitektskolens gård med virtuel udstilling af afgangsprojekter fra afgangen sommer 2006. 10 s....

  4. Comparison of computer-aided diagnosis performance and radiologist readings on the LIDC pulmonary nodule dataset

    Zhao, Luyin; Lee, Michael C.; Boroczky, Lilla; Vloemans, Victor; Opfer, Roland


    One challenge facing radiologists is the characterization of whether a pulmonary nodule detected in a CT scan is likely to be benign or malignant. We have developed an image processing and machine learning based computer-aided diagnosis (CADx) method to support such decisions by estimating the likelihood of malignancy of pulmonary nodules. The system computes 192 image features which are combined with patient age to comprise the feature pool. We constructed an ensemble of 1000 linear discriminant classifiers using 1000 feature subsets selected from the feature pool using a random subspace method. The classifiers were trained on a dataset of 125 pulmonary nodules. The individual classifier results were combined using a majority voting method to form an ensemble estimate of the likelihood of malignancy. Validation was performed on nodules in the Lung Imaging Database Consortium (LIDC) dataset for which radiologist interpretations were available. We performed calibration to reduce the differences in the internal operating points and spacing between radiologist rating and the CADx algorithm. Comparing radiologists with the CADx in assigning nodules into four malignancy categories, fair agreement was observed (κ=0.381) while binary rating yielded an agreement of (κ=0.475), suggesting that CADx can be a promising second reader in a clinical setting.

  5. Post-trial anatomical frame alignment procedure for comparison of 3D joint angle measurement from magnetic/inertial measurement units and camera-based systems.

    Li, Qingguo; Zhang, Jun-Tian


    Magnetic and inertial measurement units (MIMUs) have been widely used as an alternative to traditional camera-based motion capture systems for 3D joint kinematics measurement. Since these sensors do not directly measure position, a pre-trial anatomical calibration, either with the assistance of a special protocol/apparatus or with another motion capture system is required to establish the transformation matrices between the local sensor frame and the anatomical frame (AF) of each body segment on which the sensors are attached. Because the axes of AFs are often used as the rotational axes in the joint angle calculation, any difference in the AF determination will cause discrepancies in the calculated joint angles. Therefore, a direct comparison of joint angles between MIMU systems and camera-based systems is less meaningful because the calculated joint angles contain a systemic error due to the differences in the AF determination. To solve this problem a new post-trial AF alignment procedure is proposed. By correcting the AF misalignments, the joint angle differences caused by the difference in AF determination are eliminated and the remaining discrepancies are mainly from the measurement accuracy of the systems themselves. Lower limb joint angles from 30 walking trials were used to validate the effectiveness of the proposed AF alignment procedure. This technique could serve as a new means for calibrating magnetic/inertial sensor-based motion capture systems and correcting for AF misalignment in scenarios where joint angles are compared directly.

  6. A 3D-CTM with detailed online PSC-microphysics: analysis of the Antarctic winter 2003 by comparison with satellite observations

    F. Daerden


    Full Text Available We present the first detailed microphysical simulations which are performed online within the framework of a global 3-D chemical transport model (CTM with full chemistry. The model describes the formation and evolution of four types of polar stratospheric cloud (PSC particles. Aerosol freezing and other relevant microphysical processes are treated in a full explicit way. Each particle type is described by a binned size distribution for the number density and chemical composition. This set-up allows for an accurate treatment of sedimentation and for detailed calculation of surface area densities and optical properties. Simulations are presented for the Antarctic winter of 2003 and comparisons are made to a diverse set of satellite observations (optical and chemical measurements of POAM III and MIPAS to illustrate the capabilities of the model. This study shows that a combined resolution approach where microphysical processes are simulated in coarse-grained conditions gives good results for PSC formation and its large-scale effect on the chemical environment through processes such as denitrification, dehydration and ozone loss.

  7. Comparison of 3D laser-based photonic scans and manual anthropometric measurements of body size and shape in a validation study of 123 young Swiss men

    Nikola Koepke


    Full Text Available Background Manual anthropometric measurements are time-consuming and challenging to perform within acceptable intra- and inter-individual error margins in large studies. Three-dimensional (3D laser body scanners provide a fast and precise alternative: within a few seconds the system produces a 3D image of the body topography and calculates some 150 standardised body size measurements. Objective The aim was to enhance the small number of existing validation studies and compare scan and manual techniques based on five selected measurements. We assessed the agreement between two repeated measurements within the two methods, analysed the direct agreement between the two methods, and explored the differences between the techniques when used in regressions assessing the effect of health related determinants on body shape indices. Methods We performed two repeated body scans on 123 volunteering young men using a Vitus Smart XXL body scanner. We manually measured height, waist, hip, buttock, and chest circumferences twice for each participant according to the WHO guidelines. The participants also filled in a basic questionnaire. Results Mean differences between the two scan measurements were smaller than between the two manual measurements, and precision as well as intra-class correlation coefficients were higher. Both techniques were strongly correlated. When comparing means between both techniques we found significant differences: Height was systematically shorter by 2.1 cm, whereas waist, hip and bust circumference measurements were larger in the scans by 1.17–4.37 cm. In consequence, body shape indices also became larger and the prevalence of overweight was greater when calculated from the scans. Between 4.1% and 7.3% of the probands changed risk category from normal to overweight when classified based on the scans. However, when employing regression analyses the two measurement techniques resulted in very similar coefficients, confidence

  8. Comparison of 3D laser-based photonic scans and manual anthropometric measurements of body size and shape in a validation study of 123 young Swiss men

    Zwahlen, Marcel; Wells, Jonathan C.; Bender, Nicole; Henneberg, Maciej


    Background Manual anthropometric measurements are time-consuming and challenging to perform within acceptable intra- and inter-individual error margins in large studies. Three-dimensional (3D) laser body scanners provide a fast and precise alternative: within a few seconds the system produces a 3D image of the body topography and calculates some 150 standardised body size measurements. Objective The aim was to enhance the small number of existing validation studies and compare scan and manual techniques based on five selected measurements. We assessed the agreement between two repeated measurements within the two methods, analysed the direct agreement between the two methods, and explored the differences between the techniques when used in regressions assessing the effect of health related determinants on body shape indices. Methods We performed two repeated body scans on 123 volunteering young men using a Vitus Smart XXL body scanner. We manually measured height, waist, hip, buttock, and chest circumferences twice for each participant according to the WHO guidelines. The participants also filled in a basic questionnaire. Results Mean differences between the two scan measurements were smaller than between the two manual measurements, and precision as well as intra-class correlation coefficients were higher. Both techniques were strongly correlated. When comparing means between both techniques we found significant differences: Height was systematically shorter by 2.1 cm, whereas waist, hip and bust circumference measurements were larger in the scans by 1.17–4.37 cm. In consequence, body shape indices also became larger and the prevalence of overweight was greater when calculated from the scans. Between 4.1% and 7.3% of the probands changed risk category from normal to overweight when classified based on the scans. However, when employing regression analyses the two measurement techniques resulted in very similar coefficients, confidence intervals, and p

  9. Comparison of contrast-enhanced modified T1-weighted 3D TSE black-blood and 3D MP-RAGE sequences for the detection of cerebral metastases and brain tumours

    Kammer, N.N.; Coppenrath, E.; Treitl, K.M.; Saam, T. [Ludwig-Maximilians-University Hospital Munich, Institute for Clinical Radiology, Munich (Germany); Kooijman, H. [Philips Healthcare, Hamburg (Germany); Dietrich, O. [Ludwig-Maximilians-University Hospital Munich, Josef Lissner Laboratory for Biomedical Imaging, Institute for Clinical Radiology, Munich (Germany)


    To compare a modified T1-weighted 3D TSE black-blood sequence with sub-millimetre resolution (T1-mVISTA) with a magnetization-prepared rapid gradient echo (MP-RAGE) sequence for the diagnosis of cerebral malignomas. Forty-six patients with known or suspected intracranial tumours and 15 control patients were included in this retrospective study. All patients underwent T1-mVISTA (0.75-mm isotropic resolution, 4:43 min) and MP-RAGE (0.8-mm isotropic resolution, 4:46 minutes) at 3-Tesla in random order after application of contrast agent. Two experienced radiologists determined the number of lesions. Maximum diameter, diagnostic confidence (DC), visual assessment of contrast enhancement (VCE) and CNR{sub lesion/parenchyma} were assessed for each lesion. Significantly more lesions were detected with T1-mVISTA compared to the MP-RAGE (61 vs. 36; p < 0.05). Further, DC and VCE was rated significantly higher in the T1-mVISTA (p < 0.05 and p < 0.001). Mean CNR{sub lesion/parenchyma} was twofold higher for T1-mVISTA (24.2 ± 17.5 vs. 12.7 ± 11.5, p < 0.001). The 25 lesions detected only in T1-mVISTA were significantly smaller than those detected in both sequences (4.3 ± 3.7 mm vs. 11.3 ± 10.7 mm; p < 0.01). T1-mVISTA increases the contrast of lesions significantly compared to MP-RAGE and might therefore improve detection rates of small lesions in early stages of disease. (orig.)

  10. A comparison of atmospheric temperature over China between radiosonde observations and multiple reanalysis datasets

    Guo, Yanjun; Zhang, Siqi; Yan, Jinghui; Chen, Zhe; Ruan, Xin


    The quality controlled (RAW) and homogenized (ADJ) radiosonde temperatures within 850-30 hPa collected at 118 stations in China are compared, on a monthly mean basis, with the temperatures extracted from 8 reanalysis datasets (REA) including NCEP-1, NCEP-2, ERA-40 (ECMWF 45-yr Reanalysis), ERA-Interim, JRA-55 (Japanese 55-yr Reanalysis), 20CR (20th Century Reanalysis), MERRA (Modern Era Retrospective-Analysis), and CFSR (Climate Forecast System Reanalysis). Average differences, correlations, standard deviations, and linear trends among RAW, ADJ, and REA for the period 1981-2010 are analyzed. The results reveal significant inhomogeneity in the time series of RAW radiosonde temperature in China; an overall negative adjustment was thus employed to obtain the ADJ temperatures, and the effect of the negative adjustment is the most significant within 200-100 hPa. Such a homogenization process has removed the system errors in RAW, possibly caused by radiosonde instrument changes and observation system upgrades. Hence, the correlation is higher between ADJ and REA than that between RAW and REA. The mean difference between ADJ and REA is about 1℃ during 1981-2010, while REA are mostly cooler in the troposphere and warmer in the stratosphere than ADJ; nonetheless, they have a significant high and positive correlation and their annual variability is notably consistent. Furthermore, the linear trends in REA and ADJ both demonstrate warming in the lower-mid troposphere and cooling in the mid stratosphere, with large uncertainties found in the upper troposphere and lower stratosphere. In general, ERA-Interim, JRA-55, and MERRA are more consistent with ADJ than other reanalysis datasets.

  11. Prevalence of various comorbidities among veterans with chronic kidney disease and its comparison with other datasets.

    Patel, Nilang; Golzy, Mojgan; Nainani, Neha; Nader, Nader D; Carter, Randolph L; Lohr, James W; Arora, Pradeep


    Chronic kidney disease (CKD) has a complicated interrelationship with various comorbidities. The purpose of this study was to describe the prevalence of various comorbidities among veterans with CKD and compare it with other datasets like Kidney Early Evaluation Program (KEEP), National Health and Nutrition Examination Survey (NHANES) and Medicare. Patients who had at least one outpatient visit in year 2007 (1 January 2007 to 31 December 2007) were included in the study (n =  75,787). Glomerular filtration rate (eGFR) was estimated by the Modification of Diet in Renal Disease (MDRD) study equation. CKD prevalence was calculated based on one or two serum creatinine values at least 3 months apart. Demographic data were obtained including age, gender, race, weight, height and body mass index (BMI). The prevalence of various comorbidities was also collected based on ICD 9 codes from the problem list. The prevalence of CKD among veterans was 47.3%, much higher than estimated in the US population. Patients with CKD were more likely to have any vascular disease (36.89% vs. 14.87%), diabetes (34.18% vs. 17.83%), hypertension (86.65% vs. 57.56%), and cancer (18.69% vs. 9.23%). Irrespective of age, the prevalence of vascular disease was much higher among veterans with CKD. The prevalence of coronary artery disease, peripheral vascular disease, and cancer was much higher among elderly veterans with CKD as compared to other datasets. CKD is a growing endemic associated with a high frequency of concomitant chronic illnesses. Public health resources should be applied for early recognition and risk modification of CKD.

  12. Three-dimensional reconstruction of the guinea pig inner ear, comparison of OPFOS and light microscopy, applications of 3D reconstruction

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


    Three-dimensional (3D) reconstruction of anatomical structures can give additional insight into the morphology and function of these structures. We compare 3D reconstructions of the guinea pig inner ear, using light microscopy and orthogonal plane fluorescence optical sectioning microscopy. Applicat

  13. Quantitative Comparison of 2D and 3D MRI Techniques for the Evaluation of Chondromalacia Patellae in 3.0T MR Imaging of the Knee

    Ali Özgen


    Full Text Available INTRODUCTION: Chondromalacia patellae is a very common disorder of patellar cartilage. Magnetic resonance imaging (MRI is a powerful non-invasive tool to investigate patellar cartilage lesions. Although many MRI sequences have been used in MR imaging of the patellar cartilage and the optimal pulse sequence is controversial, fat-saturated proton density images have been considered very valuable to evaluate patellar cartilage. The purpose of this study is to quantitatively compare the diagnostic performance of various widely used 2D and 3D MRI techniques for the evaluation of chondromalacia patellae in 3.0T MR imaging of the knee using T2 mapping images as the reference standard. METHODS: Sevety-five knee MRI exams of 69 adult consecutive were included in the study. Fat-saturated T2-weighted (FST2, fat-saturated proton density (FSPD, water-only T2-weighted DIXON (T2mD, T2-weighted 3 dimensional steady state (3DT2FFE, merged multi-echo steady state (3DmFFE, and water selective T1-weighted fat-supressed (WATSc images were acquired. Quantitative comparison of grade 1 and grade 5 lesions were made using contrast-to-noise (CNR ratios. Grade 2-4 lesions were scored qualitatively and scorings of the lesions were compared statistically. Analysis of variance and Tukey’s tests were used to compare CNR data. Two sample z-test was used to compare the ratio of MR exams positive for grade 1 lesions noted on T2-mapping and other conventional sequences. Paired samples t-test was used to compare two different pulse sequences. RESULTS: In detecting grade 1 lesions, FSPD, FST2 and T2mD images were superior in comparison to other sequences. FSPD and FST2 images were statistically superior in detecting grade 2-4 lesions. Although all grade 5 lesions were noted in every single sequence, FST2 images have the highest mean CNR followed by 3DT2FFE images. DISCUSSION AND CONCLUSION: FST2 sequence is equal or superior in detecting every grade of patellar chondromalacia in

  14. Blender 3D cookbook

    Valenza, Enrico


    This book is aimed at the professionals that already have good 3D CGI experience with commercial packages and have now decided to try the open source Blender and want to experiment with something more complex than the average tutorials on the web. However, it's also aimed at the intermediate Blender users who simply want to go some steps further.It's taken for granted that you already know how to move inside the Blender interface, that you already have 3D modeling knowledge, and also that of basic 3D modeling and rendering concepts, for example, edge-loops, n-gons, or samples. In any case, it'

  15. FIT3D: Fitting optical spectra

    Sánchez, S. F.; Pérez, E.; Sánchez-Blázquez, P.; González, J. J.; Rosales-Ortega, F. F.; Cano-Díaz, M.; López-Cobá, C.; Marino, R. A.; Gil de Paz, A.; Mollá, M.; López-Sánchez, A. R.; Ascasibar, Y.; Barrera-Ballesteros, J.


    FIT3D fits optical spectra to deblend the underlying stellar population and the ionized gas, and extract physical information from each component. FIT3D is focused on the analysis of Integral Field Spectroscopy data, but is not restricted to it, and is the basis of Pipe3D, a pipeline used in the analysis of datasets like CALIFA, MaNGA, and SAMI. It can run iteratively or in an automatic way to derive the parameters of a large set of spectra.

  16. Embryonic staging using a 3D virtual reality system

    C.M. Verwoerd-Dikkeboom (Christine); A.H.J. Koning (Anton); P.J. van der Spek (Peter); N. Exalto (Niek); R.P.M. Steegers-Theunissen (Régine)


    textabstractBACKGROUND: The aim of this study was to demonstrate that Carnegie Stages could be assigned to embryos visualized with a 3D virtual reality system. METHODS: We analysed 48 3D ultrasound scans of 19 IVF/ICSI pregnancies at 7-10 weeks' gestation. These datasets were visualized as 3D 'holog

  17. 3D Digital Modelling

    Hundebøl, Jesper

    wave of new building information modelling tools demands further investigation, not least because of industry representatives' somewhat coarse parlance: Now the word is spreading -3D digital modelling is nothing less than a revolution, a shift of paradigm, a new alphabet... Research qeustions. Based...... on empirical probes (interviews, observations, written inscriptions) within the Danish construction industry this paper explores the organizational and managerial dynamics of 3D Digital Modelling. The paper intends to - Illustrate how the network of (non-)human actors engaged in the promotion (and arrest) of 3......D Modelling (in Denmark) stabilizes - Examine how 3D Modelling manifests itself in the early design phases of a construction project with a view to discuss the effects hereof for i.a. the management of the building process. Structure. The paper introduces a few, basic methodological concepts...

  18. Professional Papervision3D

    Lively, Michael


    Professional Papervision3D describes how Papervision3D works and how real world applications are built, with a clear look at essential topics such as building websites and games, creating virtual tours, and Adobe's Flash 10. Readers learn important techniques through hands-on applications, and build on those skills as the book progresses. The companion website contains all code examples, video step-by-step explanations, and a collada repository.

  19. AE3D


    AE3D solves for the shear Alfven eigenmodes and eigenfrequencies in a torodal magnetic fusion confinement device. The configuration can be either 2D (e.g. tokamak, reversed field pinch) or 3D (e.g. stellarator, helical reversed field pinch, tokamak with ripple). The equations solved are based on a reduced MHD model and sound wave coupling effects are not currently included.

  20. Comparison of analyses of the XVth QTLMAS common dataset III: Genomic Estimations of Breeding Values

    Demeure Olivier


    Full Text Available Abstract Background The QTLMAS XVth dataset consisted of pedigree, marker genotypes and quantitative trait performances of animals with a sib family structure. Pedigree and genotypes concerned 3,000 progenies among those 2,000 were phenotyped. The trait was regulated by 8 QTLs which displayed additive, imprinting or epistatic effects. The 1,000 unphenotyped progenies were considered as candidates to selection and their Genomic Estimated Breeding Values (GEBV were evaluated by participants of the XVth QTLMAS workshop. This paper aims at comparing the GEBV estimation results obtained by seven participants to the workshop. Methods From the known QTL genotypes of each candidate, two "true" genomic values (TV were estimated by organizers: the genotypic value of the candidate (TGV and the expectation of its progeny genotypic values (TBV. GEBV were computed by the participants following different statistical methods: random linear models (including BLUP and Ridge Regression, selection variable techniques (LASSO, Elastic Net and Bayesian methods. Accuracy was evaluated by the correlation between TV (TGV or TBV and GEBV presented by participants. Rank correlation of the best 10% of individuals and error in predictions were also evaluated. Bias was tested by regression of TV on GEBV. Results Large differences between methods were found for all criteria and type of genetic values (TGV, TBV. In general, the criteria ranked consistently methods belonging to the same family. Conclusions Bayesian methods - A

  1. Comparison of osteoclastogenesis and resorption activity of human osteoclasts on tissue culture polystyrene and on natural extracellular bone matrix in 2D and 3D.

    Kleinhans, C; Schmid, F F; Schmid, F V; Kluger, P J


    Bone homeostasis is maintained by osteoblasts (bone formation) and osteoclasts (bone resorption). While there have been numerous studies investigating mesenchymal stem cells and their potential to differentiate into osteoblasts as well as their interaction with different bone substitute materials, there is only limited knowledge concerning in vitro generated osteoclasts. Due to the increasing development of degradable bone-grafting materials and the need of sophisticated in vitro test methods, it is essential to gain deeper insight into the process of osteoclastogenesis and the resorption functionality of human osteoclasts. Therefore, we focused on the comparison of osteoclastogenesis and resorption activity on tissue culture polystyrene (TCPS) and bovine extracellular bone matrices (BMs). Cortical bone slices were used as two-dimensional (2D) substrates, whereas a thermally treated cancellous bone matrix was used for three-dimensional (3D) experiments. We isolated primary human monocytes and induced osteoclastogenesis by medium supplementation. Subsequently, the expression of the vitronectin receptor (αVβ3) and cathepsin K as well as the characteristic actin formation on TCPS and the two BMs were examined. The cell area of human osteoclasts was analyzed on TCPS and on BMs, whereas significantly larger osteoclasts could be detected on BMs. Additionally, we compared the diameter of the sealing zones with the measured diameter of the resorption pits on the BMs and revealed similar diameters of the sealing zones and the resorption pits. We conclude that using TCPS as culture substrate does not affect the expression of osteoclast-specific markers. The analysis of resorption activity can successfully be conducted on cortical as well as on cancellous bone matrices. For new in vitro test systems concerning bone resorption, we suggest the establishment of a 2D assay for high throughput screening of new degradable bone substitute materials with osteoclasts.

  2. Comparison of dynamic 2D and 3D brain PET for kinetic analysis of C-11 win 35,428 binding to dopamine transporters

    Kim, Sang Eun; Choi, Joon Young; Choi, Yong; Kim, Joon Young; Choe, Yearn Seong; Oh, Seung Jun; Kim, Byung Tae [College of Medicine, Sungkyunkwan Univ., Seoul (Korea, Republic of)


    3D PET data acquisition is now being used for clinical FDG-PET brain studies. However, its validity for studying kinetics of receptor-ligand interaction has not been fully evaluated. To examine the feasibility and quantitative accuracy of dynamic 3D brain PET for kinetic analysis of radioligand binding, 4 healthy volunteers and 1 Parkinson's disease patient were studied. Each subject received two 555 MBq C-11 WIN 35,428 injections and a dynamic sequence of 31 scans were acquired until 90 min p.i. in 2D and 3D mode using a GE Advance PET scanner. Both 2D and 3D image sets were reconstructed employing a Hanning filter 4.5 mm and resulting axial resolution was about 7 mm for both 2D and 3D images. The 3D data were corrected for scatter employing a method using 2D fitted Gaussian functions. Attenuation correction was performed using a 20 min transmission scan. Tissue time-activity curves were generated in the striatum and cerebellum. The forward (k3) and dissociation (k4) rate constants were calculated in the striatum using a two-compartment model, which consists of free plus nonspecifically bound (cerebellar) and specifically bound (striatal-cerebellar) compartments. The 3D kinetic results were comparable to the 2D results and within the expected range. The 3D %SE was less than 2D %SE. Striatal-to-cerebellar ratios from 2D and 3D images showed excellent correlation and agreement (r=0.994, p<0.0001, slope=0.952). The plot of striatal-to-cerebellar ratios versus time showed a linearly increasing pattern, with significantly lower RMSE in 3D than in 2D studies in linear regression analysis (0.119{+-}0.025 vs. 0.276{+-}0.087, p=0.028). These preliminary data suggest that 3D PET provides more reliable tissue kinetic data for the analysis of C-11 WIN 35,428 kinetics. Improved sensitivity in 3D may allow more accurate receptor characterization, especially in small brain structures or in low specific binding areas.

  3. Comparison of a small-scale 3D PCM thermal control model with a validated 2D PCM thermal control model

    Huang, M.J.; Eames, P.C. [Centre for Sustainable Technologies, School of the Built Environment, University of Ulster, Newtownabbey, BT37 0QB, N.Ireland (United Kingdom); Norton, B. [FOCAS Institute, Dublin Institute of Technology, Aungier Street, Dublin 2 (Ireland)


    A three-dimensional (3D) numerical model was developed to simulate the use of a phase change material linked to a photovoltaic (PV) system to control the temperature rise of the PV cells. The model can be used to predict temperatures, velocity fields and vortex formation within the system. The 3D predictions have been compared with those from a previously developed experimental validated two-dimensional (2D) finite-volume heat transfer model conjugated hydro-dynamically to solve the Navier-Stokes and energy equations. It was found that for the systems simulated with appropriate boundary conditions, the 2D model predictions compare well with those of the 3D model. The 3D model was used to predict the temperature distributions when the heat transfer to the phase change material was enhanced by high thermal conductivity pin fins. (author)

  4. Techniques and architectures for 3D interaction

    De Haan, G.


    Spatial scientific datasets are all around us, and 3D visualization is a powerful tool to explore details and structures within them. When dealing with complex spatial structures, interactive Virtual Reality (VR) systems can potentially improve exploration over desktop-based systems. However, from p

  5. Verification of the NIKE3D structural analysis code by comparison against the analytic solution for a spherical cavity under a far-field uniaxial stress

    Kansa, E.J.


    The original scope of this task was to simulate the stresses and displacements of a hard rock tunnel experimental design using a suitable three-dimensional finite element code. NIKE3D was selected as a suitable code for performing these primarily approximate linearly elastic 3D analyses, but it required modifications to include initial stress, shear traction boundary condition and excavation options. During the summer of 1988, such capabilities were installed in a special version of NIKE3D. Subsequently, we verified both the LLNL's commonly used version of NIKE3D and our private modified version against the analytic solution for a spherical cavity in an elastic material deforming under a far-field uniaxial stress. We find the results produced by the unmodified and modified versions of NIKE3D to be in good agreement with the analytic solutions, except near the cavity, where the errors in the stress field are large. As can be expected from a code based on a displacement finite element formulation, the displacements are much more accurate than the stresses calculated from the 8-noded brick elements. To reduce these errors to acceptable levels, the grid must be refined further near the cavity wall. The level of grid refinement required to simulate accurately tunneling problems that do not have spatial symmetry in three dimensions using the current NIKE3D code is likely to exceed the memory capacity of the largest CRAY 1 computers at LLNL. 8 refs., 121 figs.

  6. Comparison of 3D double inversion recovery and 2D STIR FLAIR MR sequences for the imaging of optic neuritis: pilot study

    Hodel, Jerome; Bocher, Anne-Laure; Pruvo, Jean-Pierre; Leclerc, Xavier [Hopital Roger Salengro, Department of Neuroradiology, Lille (France); Outteryck, Olivier; Zephir, Helene; Vermersch, Patrick [Hopital Roger Salengro, Department of Neurology, Lille (France); Lambert, Oriane [Fondation Ophtalmologique Rothschild, Department of Neuroradiology, Paris (France); Benadjaoud, Mohamed Amine [Radiation Epidemiology Team, Inserm, CESP Centre for Research in Epidemiology and Population Health, U1018, Villejuif (France); Chechin, David [Philips Medical Systems, Suresnes (France)


    We compared the three-dimensional (3D) double inversion recovery (DIR) magnetic resonance imaging (MRI) sequence with the coronal two-dimensional (2D) short tau inversion recovery (STIR) fluid-attenuated inversion recovery (FLAIR) for the detection of optic nerve signal abnormality in patients with optic neuritis (ON). The study group consisted of 31 patients with ON (44 pathological nerves) confirmed by visual-evoked potentials used as the reference. MRI examinations included 2D coronal STIR FLAIR and 3D DIR with 3-mm coronal reformats to match with STIR FLAIR. Image artefacts were graded for each portion of the optic nerves. Each set of MR images (2D STIR FLAIR, DIR reformats and multiplanar 3D DIR) was examined independently and separately for the detection of signal abnormality. Cisternal portion of optic nerves was better delineated with DIR (p < 0.001), while artefacts impaired analysis in four patients with STIR FLAIR. Inter-observer agreement was significantly improved (p < 0.001) on 3D DIR (κ = 0.96) compared with STIR FLAIR images (κ = 0.60). Multiplanar DIR images reached the best performance for the diagnosis of ON (95 % sensitive and 94 % specific). Our study showed a high sensitivity and specificity of 3D DIR compared with STIR FLAIR for the detection of ON. These findings suggest that the 3D DIR sequence may be more useful in patients suspected of ON. (orig.)

  7. IMRT and 3D conformal radiotherapy with or without elective nodal irradiation in locally advanced NSCLC. A direct comparison of PET-based treatment planning

    Fleckenstein, Jochen; Kremp, Katharina; Kremp, Stephanie; Palm, Jan; Ruebe, Christian [Saarland University Medical School, Department of Radiotherapy and Radiation Oncology, Homburg/Saar (Germany)


    The potential of intensity-modulated radiation therapy (IMRT) as opposed to three-dimensional conformal radiotherapy (3D-CRT) is analyzed for two different concepts of fluorodeoxyglucose positron emission tomography (FDG PET)-based target volume delineation in locally advanced non-small cell lung cancer (LA-NSCLC): involved-field radiotherapy (IF-RT) vs. elective nodal irradiation (ENI). Treatment planning was performed for 41 patients with LA-NSCLC, using four different planning approaches (3D-CRT-IF, 3D-CRT-ENI, IMRT-IF, IMRT-ENI). ENI included a boost irradiation after 50 Gy. For each plan, maximum dose escalation was calculated based on prespecified normal tissue constraints. The maximum prescription dose (PD), tumor control probability (TCP), conformal indices (CI), and normal tissue complication probabilities (NTCP) were analyzed. IMRT resulted in statistically significant higher prescription doses for both target volume concepts as compared with 3D-CRT (ENI: 68.4 vs. 60.9 Gy, p < 0.001; IF: 74.3 vs. 70.1 Gy, p < 0.03). With IMRT-IF, a PD of at least 66 Gy was achieved for 95 % of all plans. For IF as compared with ENI, there was a considerable theoretical increase in TCP (IMRT: 27.3 vs. 17.7 %, p < 0.00001; 3D-CRT: 20.2 vs. 9.9 %, p < 0.00001). The esophageal NTCP showed a particularly good sparing with IMRT vs. 3D-CRT (ENI: 12.3 vs. 30.9 % p < 0.0001; IF: 15.9 vs. 24.1 %; p < 0.001). The IMRT technique and IF target volume delineation allow a significant dose escalation and an increase in TCP. IMRT results in an improved sparing of OARs as compared with 3D-CRT at equivalent dose levels. (orig.) [German] Das Potenzial der intensitaetsmodulierten Strahlentherapie (IMRT) soll im Rahmen der FDG-PET basierten Bestrahlungsplanung des lokal fortgeschrittenen nichtkleinzelligen Bronchialkarzinoms (LA-NSCLC) fuer 2 Zielvolumenansaetze (Involved-Field-Bestrahlung, IF) sowie elektive Nodalbestrahlung (ENI) geprueft und mit der 3-D-konformalen Strahlentherapie (3-D

  8. Radiochromic 3D Detectors

    Oldham, Mark


    Radiochromic materials exhibit a colour change when exposed to ionising radiation. Radiochromic film has been used for clinical dosimetry for many years and increasingly so recently, as films of higher sensitivities have become available. The two principle advantages of radiochromic dosimetry include greater tissue equivalence (radiologically) and the lack of requirement for development of the colour change. In a radiochromic material, the colour change arises direct from ionising interactions affecting dye molecules, without requiring any latent chemical, optical or thermal development, with important implications for increased accuracy and convenience. It is only relatively recently however, that 3D radiochromic dosimetry has become possible. In this article we review recent developments and the current state-of-the-art of 3D radiochromic dosimetry, and the potential for a more comprehensive solution for the verification of complex radiation therapy treatments, and 3D dose measurement in general.

  9. 3D Spectroscopic Instrumentation

    Bershady, Matthew A


    In this Chapter we review the challenges of, and opportunities for, 3D spectroscopy, and how these have lead to new and different approaches to sampling astronomical information. We describe and categorize existing instruments on 4m and 10m telescopes. Our primary focus is on grating-dispersed spectrographs. We discuss how to optimize dispersive elements, such as VPH gratings, to achieve adequate spectral resolution, high throughput, and efficient data packing to maximize spatial sampling for 3D spectroscopy. We review and compare the various coupling methods that make these spectrographs ``3D,'' including fibers, lenslets, slicers, and filtered multi-slits. We also describe Fabry-Perot and spatial-heterodyne interferometers, pointing out their advantages as field-widened systems relative to conventional, grating-dispersed spectrographs. We explore the parameter space all these instruments sample, highlighting regimes open for exploitation. Present instruments provide a foil for future development. We give an...

  10. 3D Projection Installations

    Halskov, Kim; Johansen, Stine Liv; Bach Mikkelsen, Michelle


    Three-dimensional projection installations are particular kinds of augmented spaces in which a digital 3-D model is projected onto a physical three-dimensional object, thereby fusing the digital content and the physical object. Based on interaction design research and media studies, this article...... contributes to the understanding of the distinctive characteristics of such a new medium, and identifies three strategies for designing 3-D projection installations: establishing space; interplay between the digital and the physical; and transformation of materiality. The principal empirical case, From...... Fingerplan to Loop City, is a 3-D projection installation presenting the history and future of city planning for the Copenhagen area in Denmark. The installation was presented as part of the 12th Architecture Biennale in Venice in 2010....

  11. Interaktiv 3D design

    Villaume, René Domine; Ørstrup, Finn Rude


    Projektet undersøger potentialet for interaktiv 3D design via Internettet. Arkitekt Jørn Utzons projekt til Espansiva blev udviklet som et byggesystem med det mål, at kunne skabe mangfoldige planmuligheder og mangfoldige facade- og rumudformninger. Systemets bygningskomponenter er digitaliseret som...... 3D elementer og gjort tilgængelige. Via Internettet er det nu muligt at sammenstille og afprøve en uendelig  række bygningstyper som  systemet blev tænkt og udviklet til....

  12. Midsagittal plane extraction from brain images based on 3D SIFT.

    Wu, Huisi; Wang, Defeng; Shi, Lin; Wen, Zhenkun; Ming, Zhong


    Midsagittal plane (MSP) extraction from 3D brain images is considered as a promising technique for human brain symmetry analysis. In this paper, we present a fast and robust MSP extraction method based on 3D scale-invariant feature transform (SIFT). Unlike the existing brain MSP extraction methods, which mainly rely on the gray similarity, 3D edge registration or parameterized surface matching to determine the fissure plane, our proposed method is based on distinctive 3D SIFT features, in which the fissure plane is determined by parallel 3D SIFT matching and iterative least-median of squares plane regression. By considering the relative scales, orientations and flipped descriptors between two 3D SIFT features, we propose a novel metric to measure the symmetry magnitude for 3D SIFT features. By clustering and indexing the extracted SIFT features using a k-dimensional tree (KD-tree) implemented on graphics processing units, we can match multiple pairs of 3D SIFT features in parallel and solve the optimal MSP on-the-fly. The proposed method is evaluated by synthetic and in vivo datasets, of normal and pathological cases, and validated by comparisons with the state-of-the-art methods. Experimental results demonstrated that our method has achieved a real-time performance with better accuracy yielding an average yaw angle error below 0.91° and an average roll angle error no more than 0.89°.

  13. MR Imaging of Prostate Cancer: Diffusion Weighted Imaging and (3D Hydrogen 1 (1H MR Spectroscopy in Comparison with Histology

    J. Yamamura


    Full Text Available Purpose. To evaluate retrospectively the impact of diffusion weighted imaging (DWI and (3D hydrogen 1 (1H MR-spectroscopy (MRS on the detection of prostatic cancer in comparison to histological examinations. Materials and Methods: 50 patients with suspicion of prostate cancer underwent a MRI examination at a 1.5T scanner. The prostate was divided into sextants. Regions of interest were placed in each sextant to evaluate the apparent diffusion coefficient (ADC-values. The results of the DWI as well as MRS were compared retrospectively with the findings of the histological examination. Sensitivity and specificity of ADC and metabolic ratio (MET—both separately and in combination—for identification of tumor tissue was computed for variable discrimination thresholds to evaluate its receiver operator characteristic (ROC. An association between ADC, MET and Gleason score was tested by the non-parametric Spearman -test. Results. The average ADC-value was 1.65±0.32mm2/s × 10-3 in normal tissue and 0.96±0.24 mm2/s × 10-3 in tumor tissue (mean ± 1 SD. MET was 0.418±0.431 in normal tissue and 2.010±1.649 in tumor tissue. The area under the ROC curve was 0.966 (95%-confidence interval 0.941–0.991 and 0.943 (0.918–0.968 for DWI and MRS, respectively. There was a highly significant negative correlation between ADC-value and the Gleason score in the tumor-positive tissue probes (=62, =−0.405, =.001. MRS did not show a significant correlation with the Gleason score (=0.117, =.366. By using both the DWI and MRS, the regression model provided sensitivity and specificity for detection of tumor of 91.9% and 98.3%, respectively. Conclusion. The results of our study showed that both DWI and MRS should be considered as an additional and complementary tool to the T2-weighted MRI for detecting prostate cancer.

  14. Ozone data assimilation with GEOS-Chem: a comparison between 3-D-Var, 4-D-Var, and suboptimal Kalman filter approaches

    K. Singh


    measurements of 1–5 %. Two sequential assimilation approaches (three dimensional variational and suboptimal KF, although derived from different theoretical considerations, provide similar ozone estimates, with relative differences of 5–10 % between the analyses and ozonesonde measurements.

    Adjoint sensitivity analysis techniques are used to explore the role of of uncertainties in ozone precursors and their emissions on the distribution of tropospheric ozone. A novel technique is introduced that projects 3-D-Variational increments back to an equivalent initial condition, which facilitates comparison with 4-D variational techniques.

  15. Comparison of 3D turbo spin-echo SPACE sequences with conventional 2D MRI sequences to assess the shoulder joint

    Kloth, Jost Karsten, E-mail: [Diagnostic and Interventional Radiology, University Hospital Heidelberg, Im Neuenheimer Feld 110, D-69120 Heidelberg (Germany); Winterstein, Marianne, E-mail: [Diagnostic and Interventional Radiology, University Hospital Heidelberg, Im Neuenheimer Feld 110, D-69120 Heidelberg (Germany); Akbar, Michael, E-mail: [Orthopedic and Trauma Surgery, University Hospital Heidelberg, Schlierbacher Landstraße 200a, D-69118 Heidelberg (Germany); Meyer, Esther, E-mail: [Siemens Healthcare, Erlangen (Germany); Paul, Dominik, E-mail: [Siemens Healthcare, Erlangen (Germany); Kauczor, Haus-Ulrich, E-mail: [Diagnostic and Interventional Radiology, University Hospital Heidelberg, Im Neuenheimer Feld 110, D-69120 Heidelberg (Germany); Weber, Marc-André, E-mail: [Diagnostic and Interventional Radiology, University Hospital Heidelberg, Im Neuenheimer Feld 110, D-69120 Heidelberg (Germany)


    Highlights: • 3D SPACE and conventional 2D TSE MRI for assessment of the shoulder joint were compared. • Concordance for most pathologys was substantial to almost perfect. • Examination time could be reduced up to 8 min (27%). • Regarding rotator cuff injuries an additional sagittal T2w TSE sequence in 3D protocol is recommended. - Abstract: Purpose: To determine the accuracy and reliability of three-dimensional (3D) T1- and proton density (PD)-weighted turbo spin-echo (TSE) sampling perfection with application-optimized contrasts using different flip-angle evolution (SPACE) compared with conventional 2D sequences in assessment of the shoulder-joint. Materials and methods: Ninety-three subjects were examined on a 3-T MRI system with both conventional 2D-TSE sequences in T1-, T2- and PD-weighting and 3D SPACE sequences in T1- and PD-weighting. All examinations were assessed independently by two reviewers for common pathologies of the shoulder-joint. Agreement between 2D- and 3D-sequences and inter-observer-agreement was evaluated using kappa-statistics. Results: Using conventional 2D TSE sequences as standard of reference, sensitivity, specificity, and accuracy values of 3D SPACE were 81.8%, 95.1%, and 93.5% for injuries of the supraspinatus-tendon (SSP), 81.3%, 93.5%, and 91.4% for the cartilage layer and 82.4%, 98.5%, and 97.5% for the long biceps tendon. Concordance between 2D and 3D was almost perfect for tendinopathies of the SSP (κ = 0.85), osteoarthritis (κ = 1), luxation of the biceps tendon (κ = 1) and adjacent bone marrow (κ = 0.92). Inter-observer-agreement was generally higher for conventional 2D TSE sequences (κ, 0.23–1.0), when compared to 3D SPACE sequences (κ, −0.33 to 1.0) except for disorders of the long biceps tendon and supraspinatus tendon rupture. Conclusion: Because of substantial and almost perfect concordance with conventional 2D TSE sequences for common shoulder pathologies, MRI examination-time can be reduced by nearly 40

  16. Tangible 3D Modelling

    Hejlesen, Aske K.; Ovesen, Nis


    This paper presents an experimental approach to teaching 3D modelling techniques in an Industrial Design programme. The approach includes the use of tangible free form models as tools for improving the overall learning. The paper is based on lecturer and student experiences obtained through...

  17. Shaping 3-D boxes

    Stenholt, Rasmus; Madsen, Claus B.


    Enabling users to shape 3-D boxes in immersive virtual environments is a non-trivial problem. In this paper, a new family of techniques for creating rectangular boxes of arbitrary position, orientation, and size is presented and evaluated. These new techniques are based solely on position data...

  18. 3D Wire 2015

    Jordi, Moréton; F, Escribano; J. L., Farias

    This document is a general report on the implementation of gamification in 3D Wire 2015 event. As the second gamification experience in this event, we have delved deeply in the previous objectives (attracting public areas less frequented exhibition in previous years and enhance networking) and ha......, improves socialization and networking, improves media impact, improves fun factor and improves encouragement of the production team....

  19. 3D photoacoustic imaging

    Carson, Jeffrey J. L.; Roumeliotis, Michael; Chaudhary, Govind; Stodilka, Robert Z.; Anastasio, Mark A.


    Our group has concentrated on development of a 3D photoacoustic imaging system for biomedical imaging research. The technology employs a sparse parallel detection scheme and specialized reconstruction software to obtain 3D optical images using a single laser pulse. With the technology we have been able to capture 3D movies of translating point targets and rotating line targets. The current limitation of our 3D photoacoustic imaging approach is its inability ability to reconstruct complex objects in the field of view. This is primarily due to the relatively small number of projections used to reconstruct objects. However, in many photoacoustic imaging situations, only a few objects may be present in the field of view and these objects may have very high contrast compared to background. That is, the objects have sparse properties. Therefore, our work had two objectives: (i) to utilize mathematical tools to evaluate 3D photoacoustic imaging performance, and (ii) to test image reconstruction algorithms that prefer sparseness in the reconstructed images. Our approach was to utilize singular value decomposition techniques to study the imaging operator of the system and evaluate the complexity of objects that could potentially be reconstructed. We also compared the performance of two image reconstruction algorithms (algebraic reconstruction and l1-norm techniques) at reconstructing objects of increasing sparseness. We observed that for a 15-element detection scheme, the number of measureable singular vectors representative of the imaging operator was consistent with the demonstrated ability to reconstruct point and line targets in the field of view. We also observed that the l1-norm reconstruction technique, which is known to prefer sparseness in reconstructed images, was superior to the algebraic reconstruction technique. Based on these findings, we concluded (i) that singular value decomposition of the imaging operator provides valuable insight into the capabilities of

  20. Limb darkening laws for two exoplanet host stars derived from 3D stellar model atmospheres. Comparison with 1D models and HST light curve observations

    Hayek, W.; Sing, D.; Pont, F.; Asplund, M.


    We compare limb darkening laws derived from 3D hydrodynamical model atmospheres and 1D hydrostatic MARCS models for the host stars of two well-studied transiting exoplanet systems, the late-type dwarfs HD 209458 and HD 189733. The surface brightness distribution of the stellar disks is calculated for a wide spectral range using 3D LTE spectrum formation and opacity sampling⋆. We test our theoretical predictions using least-squares fits of model light curves to wavelength-integrated primary eclipses that were observed with the Hubble Space Telescope (HST). The limb darkening law derived from the 3D model of HD 209458 in the spectral region between 2900 Å and 5700 Å produces significantly better fits to the HST data, removing systematic residuals that were previously observed for model light curves based on 1D limb darkening predictions. This difference arises mainly from the shallower mean temperature structure of the 3D model, which is a consequence of the explicit simulation of stellar surface granulation where 1D models need to rely on simplified recipes. In the case of HD 189733, the model atmospheres produce practically equivalent limb darkening curves between 2900 Å and 5700 Å, partly due to obstruction by spectral lines, and the data are not sufficient to distinguish between the light curves. We also analyze HST observations between 5350 Å and 10 500 Å for this star; the 3D model leads to a better fit compared to 1D limb darkening predictions. The significant improvement of fit quality for the HD 209458 system demonstrates the higher degree of realism of 3D hydrodynamical models and the importance of surface granulation for the formation of the atmospheric radiation field of late-type stars. This result agrees well with recent investigations of limb darkening in the solar continuum and other observational tests of the 3D models. The case of HD 189733 is no contradiction as the model light curves are less sensitive to the temperature stratification of

  1. 3D change detection - Approaches and applications

    Qin, Rongjun; Tian, Jiaojiao; Reinartz, Peter


    Due to the unprecedented technology development of sensors, platforms and algorithms for 3D data acquisition and generation, 3D spaceborne, airborne and close-range data, in the form of image based, Light Detection and Ranging (LiDAR) based point clouds, Digital Elevation Models (DEM) and 3D city models, become more accessible than ever before. Change detection (CD) or time-series data analysis in 3D has gained great attention due to its capability of providing volumetric dynamics to facilitate more applications and provide more accurate results. The state-of-the-art CD reviews aim to provide a comprehensive synthesis and to simplify the taxonomy of the traditional remote sensing CD techniques, which mainly sit within the boundary of 2D image/spectrum analysis, largely ignoring the particularities of 3D aspects of the data. The inclusion of 3D data for change detection (termed 3D CD), not only provides a source with different modality for analysis, but also transcends the border of traditional top-view 2D pixel/object-based analysis to highly detailed, oblique view or voxel-based geometric analysis. This paper reviews the recent developments and applications of 3D CD using remote sensing and close-range data, in support of both academia and industry researchers who seek for solutions in detecting and analyzing 3D dynamics of various objects of interest. We first describe the general considerations of 3D CD problems in different processing stages and identify CD types based on the information used, being the geometric comparison and geometric-spectral analysis. We then summarize relevant works and practices in urban, environment, ecology and civil applications, etc. Given the broad spectrum of applications and different types of 3D data, we discuss important issues in 3D CD methods. Finally, we present concluding remarks in algorithmic aspects of 3D CD.

  2. Classification of forest development stages from national low-density lidar datasets: a comparison of machine learning methods

    R. Valbuena


    Full Text Available The area-based method has become a widespread approach in airborne laser scanning (ALS, being mainly employed for the estimation of continuous variables describing forest attributes: biomass, volume, density, etc. However, to date, classification methods based on machine learning, which are fairly common in other remote sensing fields, such as land use / land cover classification using multispectral sensors, have been largely overseen in forestry applications of ALS. In this article, we wish to draw the attention on statistical methods predicting discrete responses, for supervised classification of ALS datasets. A wide spectrum of approaches are reviewed: discriminant analysis (DA using various classifiers –maximum likelihood, minimum volume ellipsoid, naïve Bayes–, support vector machine (SVM, artificial neural networks (ANN, random forest (RF and nearest neighbour (NN methods. They are compared in the context of a classification of forest areas into development classes (DC used in practical silvicultural management in Finland, using their low-density national ALS dataset. We observed that RF and NN had the most balanced error matrices, with cross-validated predictions which were mainly unbiased for all DCs. Although overall accuracies were higher for SVM and ANN, their results were very dissimilar across DCs, and they can therefore be only advantageous if certain DCs are targeted. DA methods underperformed in comparison to other alternatives, and were only advantageous for the detection of seedling stands. These results show that, besides the well demonstrated capacity of ALS for quantifying forest stocks, there is a great deal of potential for predicting categorical variables in general, and forest types in particular. In conclusion, we consider that the presented methodology shall also be adapted to the type of forest classes that can be relevant to Mediterranean ecosystems, opening a range of possibilities for future research, in which

  3. Dose escalation in prostate radiotherapy up to 82 Gy using simultaneous integrated boost. Direct comparison of acute and late toxicity with 3D-CRT 74 Gy and IMRT 78 Gy

    Dolezel, Martin; Odrazka, Karel; Vanasek, Jaroslav [Oncology Center, Multiscan and Pardubice Regional Hospital, Pardubice (Czech Republic); Vaculikova, Miloslava [Dept. of Oncology, Hospital Nachod (Czech Republic); Sefrova, Jana; Paluska, Petr; Zouhar, Milan; Jansa, Jan; Macingova, Zuzana; Jarosova, Lida [Dept. of Oncology and Radiotherapy, Univ. Hospital Hradec Kralove (Czech Republic); Brodak, Milos; Moravek, Petr [Dept. of Urology, Univ. Hospital Hradec Kralove (Czech Republic); Hartmann, Igor [Dept. of Urology, Univ. Hospital Olomouc (Czech Republic)


    Purpose: To compare acute and late toxicity after three-dimensional conformal radiotherapy to the prostate to 74 Gy (3D-CRT) with intensity-modulated radiotherapy to 78 Gy (IMRT 78) and IMRT using simultaneous integrated boost to 82 Gy (IMRT/SIB 82). Patients and methods: 94 patients treated with 3D-CRT to the prostate and base of seminal vesicles to 74 Gy represented the first group. The second group consisted of 138 patients subjected to IMRT covering the prostate and base of seminal vesicles to 78 Gy. The last group was treated with IMRT using SIB. The prescribed doses were 82 Gy and 73.8 Gy in 42 fractions to the prostate and seminal vesicles. Late toxicity was prospectively scored according to the RTOG/FC-LENT scale. Results: Acute gastrointestinal toxicity {>=} grade 2 occurred in 35.1% of patients treated with 3D-CRT, in 16% subjected to IMRT 78, and in 7.7% receiving IMRT/SIB 82. Acute genitourinary toxicity {>=} grade 2 was observed in 26.6% (3D-CRT), 33% (IMRT 78), and 30.7% (IMRT/SIB 82). At 3 years, the estimated cumulative incidence of grade 3 late gastrointestinal toxicity was 14% for 3D-CRT, 5% for IMRT 78, and 2% for IMRT/SIB 82. The difference became significant (log rank p = 0.02). The estimated cumulative incidence of grade 3 late genitourinary toxicity was 9% (3D-CRT), 7% (IMRT 78), and 6% (IMRT/SIB 82) without statistical differences (log rank p = 0.32). Conclusion: SIB enables dose escalation up to 82 Gy with a lower rate of gastrointestinal toxicity grade 3 in comparison with 3D-CRT up to 74 Gy. (orig.)

  4. Evaluation and comparison of 3D-QSAR CoMSIA models for CDK1, CDK5, and GSK-3 inhibition by paullones

    Kunick, Conrad; Lauenroth, Kathrin; Wieking, Karen;


    With a view to the rational design of selective GSK-3beta inhibitors, 3D-QSAR CoMSIA models were developed for the inhibition of the three serine/threonine kinases CDK1/cyclin B, CDK5/p25, and GSK-3beta by compounds from the paullone inhibitor family. The models are based on the kinase inhibition...

  5. Stereological measures of trabecular bone structure: comparison of 3D micro computed tomography with 2D histological sections in human proximal tibial bone biopsies

    Thomsen, Jesper Skovhus; Laib, A.; Koller, B.;


    tibial metaphysis. The biopsies were embedded in methylmetacrylate before microCT scanning in a Scanco microCT 40 scanner at a resolution of 20 x 20 x 20 microm3, and the 3D data sets were analysed with a computer program. After microCT scanning, 16 sections were cut from the central 2 mm of each biopsy...

  6. Accuracy of x-ray image-based 3D localization from two C-arm views: a comparison between an ideal system and a real device

    Brost, Alexander; Strobel, Norbert; Yatziv, Liron; Gilson, Wesley; Meyer, Bernhard; Hornegger, Joachim; Lewin, Jonathan; Wacker, Frank


    arm X-ray imaging devices are commonly used for minimally invasive cardiovascular or other interventional procedures. Calibrated state-of-the-art systems can, however, not only be used for 2D imaging but also for three-dimensional reconstruction either using tomographic techniques or even stereotactic approaches. To evaluate the accuracy of X-ray object localization from two views, a simulation study assuming an ideal imaging geometry was carried out first. This was backed up with a phantom experiment involving a real C-arm angiography system. Both studies were based on a phantom comprising five point objects. These point objects were projected onto a flat-panel detector under different C-arm view positions. The resulting 2D positions were perturbed by adding Gaussian noise to simulate 2D point localization errors. In the next step, 3D point positions were triangulated from two views. A 3D error was computed by taking differences between the reconstructed 3D positions using the perturbed 2D positions and the initial 3D positions of the five points. This experiment was repeated for various C-arm angulations involving angular differences ranging from 15° to 165°. The smallest 3D reconstruction error was achieved, as expected, by views that were 90° degrees apart. In this case, the simulation study yielded a 3D error of 0.82 mm +/- 0.24 mm (mean +/- standard deviation) for 2D noise with a standard deviation of 1.232 mm (4 detector pixels). The experimental result for this view configuration obtained on an AXIOM Artis C-arm (Siemens AG, Healthcare Sector, Forchheim, Germany) system was 0.98 mm +/- 0.29 mm, respectively. These results show that state-of-the-art C-arm systems can localize instruments with millimeter accuracy, and that they can accomplish this almost as well as an idealized theoretical counterpart. High stereotactic localization accuracy, good patient access, and CT-like 3D imaging capabilities render state-of-the-art C-arm systems ideal devices for X

  7. Sub-Millimeter T2 Weighted fMRI at 7 T: Comparison of 3D-GRASE and 2D SE-EPI

    Valentin G. Kemper


    Full Text Available Functional magnetic resonance imaging (fMRI allows studying human brain function non-invasively up to the spatial resolution of cortical columns and layers. Most fMRI acquisitions rely on the blood oxygenation level dependent (BOLD contrast employing T2* weighted 2D multi-slice echo-planar imaging (EPI. At ultra-high magnetic field (i.e. 7 T and above, it has been shown experimentally and by simulation, that T2 weighted acquisitions yield a signal that is spatially more specific to the site of neuronal activity at the cost of functional sensitivity. This study compared two T2 weighted imaging sequences, inner-volume 3D Gradient-and-Spin-Echo (3D-GRASE and 2D Spin-Echo EPI (SE-EPI, with evaluation of their imaging point-spread function, functional specificity, and functional sensitivity at sub-millimeter resolution. Simulations and measurements of the imaging point-spread function revealed that the strongest anisotropic blurring in 3D-GRASE (along the second phase-encoding direction was about 60 % higher than the strongest anisotropic blurring in 2D SE-EPI (along the phase-encoding direction In a visual paradigm, the BOLD sensitivity of 3D-GRASE was found to be superior due to its higher temporal signal-to-noise ratio. High resolution cortical depth profiles suggested that the contrast mechanisms are similar between the two sequences, however, 2D SE-EPI had a higher surface bias owing to the higher T2* contribution of the longer in-plane EPI echo-train for full field of view compared to the reduced field of view of zoomed 3D-GRASE.

  8. Intensity modulated radiotherapy as neoadjuvant chemoradiation for the treatment of patients with locally advanced pancreatic cancer. Outcome analysis and comparison with a 3D-treated patient cohort

    Combs, S.E.; Habermehl, D.; Kessel, K.; Brecht, I. [Univ. Hospital of Heidelberg (Germany). Dept. of Radiation Oncology; Bergmann, F.; Schirmacher, P. [Univ. Hospital of Heidelberg (Germany). Dept. of Pathology; Werner, J.; Buechler, M.W. [Univ. Hospital of Heidelberg (Germany). Dept. of Surgery; Jaeger, D. [National Center for Tumor Diseases (NCT), Heidelberg (Germany); Debus, J. [Univ. Hospital of Heidelberg (Germany). Dept. of Radiation Oncology; Deutsches Krebsforschungszentrum (DKFZ), Heidelberg (Germany). Clinical Cooperation Unit Radiation Oncology


    Background: To evaluate outcome after intensity modulated radiotherapy (IMRT) compared to 3D conformal radiotherapy (3D-RT) as neoadjuvant treatment in patients with locally advanced pancreatic cancer (LAPC). Materials and methods: In total, 57 patients with LAPC were treated with IMRT and chemotherapy. A median total dose of 45 Gy to the PTV {sub baseplan} and 54 Gy to the PTV {sub boost} in single doses of 1.8 Gy for the PTV {sub baseplan} and median single doses of 2.2 Gy in the PTV {sub boost} were applied. Outcomes were evaluated and compared to a large cohort of patients treated with 3D-RT. Results: Overall treatment was well tolerated in all patients and IMRT could be completed without interruptions. Median overall survival was 11 months (range 5-37.5 months). Actuarial overall survival at 12 and 24 months was 36 % and 8 %, respectively. A significant impact on overall survival could only be observed for a decrease in CA 19-9 during treatment, patients with less pre-treatment CA 19-9 than the median, as well as weight loss during treatment. Local progression-free survival was 79 % after 6 months, 39 % after 12 months, and 13 % after 24 months. No factors significantly influencing local progression-free survival could be identified. There was no difference in overall and progression-free survival between 3D-RT and IMRT. Secondary resectability was similar in both groups (26 % vs. 28 %). Toxicity was comparable and consisted mainly of hematological toxicity due to chemotherapy. Conclusion: IMRT leads to a comparable outcome compared to 3D-RT in patients with LAPC. In the future, the improved dose distribution, as well as advances in image-guided radiotherapy (IGRT) techniques, may improve the use of IMRT in local dose escalation strategies to potentially improve outcome. (orig.)

  9. Heart dose reduction in breast cancer treatment with simultaneous integrated boost. Comparison of treatment planning and dosimetry for a novel hybrid technique and 3D-CRT

    Joest, Vincent; Kretschmer, Matthias; Sabatino, Marcello; Wuerschmidt, Florian; Dahle, Joerg; Lorenzen, Joern [Radiological Alliance, Hamburg (Germany); Ueberle, Friedrich [University of Applied Sciences, Faculty Life Sciences, Hamburg (Germany)


    The present study compares in silico treatment plans of clinically established three-dimensional conformal radiotherapy (3D-CRT) with a hybrid technique consisting of intensity-modulated radiotherapy (IMRT) and volumetric modulated arc radiotherapy (VMAT) during normally fractionated radiation of mammary carcinomas with simultaneous integrated boost on the basis of dose-volume histogram (DVH) parameters. Radiation treatment planning was performed with a hybrid and a 3D-CRT treatment plan for 20 patients. Hybrid plans were implemented with two tangential IMRT fields and a VMAT field in the angular range of the tangents. Verification of the plan was performed with a manufacturer-independent measurement system consisting of a detector array and rotation unit. The mean values of the heart dose for the entire patient collective were 3.6 ± 2.5 Gy for 3D-CRT and 2.9 ± 2.1 Gy for the hybrid technique (p < 0.01). For the left side (n = 10), the mean values for the left anterior descending artery were 21.8 ± 7.4 Gy for 3D-CRT and 17.6 ± 7.4 Gy for the hybrid technique (p < 0.01). The mean values of the ipsilateral lung were 11.9 ± 1.6 Gy for 3D-CRT and 10.5 ± 1.3 Gy for the hybrid technique (p < 0.01). Calculated dose distributions in the hybrid arm were in good accordance with measured dose (on average 95.6 ± 0.5 % for γ < 1 and 3 %/3 mm). The difference of the mean treatment time per fraction was 7 s in favor of 3D-CRT. Compared with the established 3D-CRT technique, the hybrid technique allows for a decrease in dose, particularly of the mean heart and lung dose with comparable target volume acquisition and without disadvantageous low-dose load of contralateral structures. Uncomplicated implementation of the hybrid technique was demonstrated in this context. The hybrid technique combines the advantages of tangential IMRT with the superior sparing of organs at risk by VMAT. (orig.) [German] Die vorliegende Studie vergleicht ''in silico

  10. Unoriented 3d TFTs

    Bhardwaj, Lakshya


    This paper generalizes two facts about oriented 3d TFTs to the unoriented case. On one hand, it is known that oriented 3d TFTs having a topological boundary condition admit a state-sum construction known as the Turaev-Viro construction. This is related to the string-net construction of fermionic phases of matter. We show how Turaev-Viro construction can be generalized to unoriented 3d TFTs. On the other hand, it is known that the "fermionic" versions of oriented TFTs, known as Spin-TFTs, can be constructed in terms of "shadow" TFTs which are ordinary oriented TFTs with an anomalous Z_2 1-form symmetry. We generalize this correspondence to Pin+ TFTs by showing that they can be constructed in terms of ordinary unoriented TFTs with anomalous Z_2 1-form symmetry having a mixed anomaly with time-reversal symmetry. The corresponding Pin+ TFT does not have any anomaly for time-reversal symmetry however and hence it can be unambiguously defined on a non-orientable manifold. In case a Pin+ TFT admits a topological bou...

  11. Volumetric modulated arc planning for lung stereotactic body radiotherapy using conventional and unflattened photon beams: a dosimetric comparison with 3D technique

    Zhang Geoffrey G


    Full Text Available Abstract Purpose Frequently, three-dimensional (3D conformal beams are used in lung cancer stereotactic body radiotherapy (SBRT. Recently, volumetric modulated arc therapy (VMAT was introduced as a new treatment modality. VMAT techniques shorten delivery time, reducing the possibility of intrafraction target motion. However dose distributions can be quite different from standard 3D therapy. This study quantifies those differences, with focus on VMAT plans using unflattened photon beams. Methods A total of 15 lung cancer patients previously treated with 3D or VMAT SBRT were randomly selected. For each patient, non-coplanar 3D, coplanar and non-coplanar VMAT and flattening filter free VMAT (FFF-VMAT plans were generated to meet the same objectives with 50 Gy covering 95% of the PTV. Two dynamic arcs were used in each VMAT plan. The couch was set at ± 5° to the 0° straight position for the two non-coplanar arcs. Pinnacle version 9.0 (Philips Radiation Oncology, Fitchburg WI treatment planning system with VMAT capabilities was used. We analyzed the conformity index (CI, which is the ratio of the total volume receiving at least the prescription dose to the target volume receiving at least the prescription dose; the conformity number (CN which is the ratio of the target coverage to CI; and the gradient index (GI which is the ratio of the volume of 50% of the prescription isodose to the volume of the prescription isodose; as well as the V20, V5, and mean lung dose (MLD. Paired non-parametric analysis of variance tests with post-tests were performed to examine the statistical significance of the differences of the dosimetric indices. Results Dosimetric indices CI, CN and MLD all show statistically significant improvement for all studied VMAT techniques compared with 3D plans (p Conclusion Besides the advantage of faster delivery times, VMAT plans demonstrated better conformity to target, sharper dose fall-off in normal tissues and lower dose to

  12. Single breath-hold assessment of cardiac function using an accelerated 3D single breath-hold acquisition technique - comparison of an intravascular and extravascular contrast agent

    Makowski Marcus R


    Full Text Available Abstract Background Cardiovascular magnetic resonance (CMR is the current gold standard for the assessment of left ventricular (LV function. Repeated breath-holds are needed for standard multi-slice 2D cine steady-state free precession sequences (M2D-SSFP. Accelerated single breath-hold techniques suffer from low contrast between blood pool and myocardium. In this study an intravascular contrast agent was prospectively compared to an extravascular contrast agent for the assessment of LV function using a single-breath-hold 3D-whole-heart cine SSFP sequence (3D-SSFP. Methods LV function was assessed in fourteen patients on a 1.5 T MR-scanner (Philips Healthcare using 32-channel coil technology. Patients were investigated twice using a 3D-SSFP sequence (acquisition time 18–25 s after Gadopentetate dimeglumine (GdD, day 1 and Gadofosveset trisodium (GdT, day 2 administration. Image acquisition was accelerated using sensitivity encoding in both phase encoding directions (4xSENSE. CNR and BMC were both measured between blood and myocardium. The CNR incorporated noise measurements, while the BMC represented the coeffiancy between the signal from blood and myocardium [1]. Contrast to noise ratio (CNR, blood to myocardium contrast (BMC, image quality, LV functional parameters and intra-/interobserver variability were compared. A M2D-SSFP sequence was used as a reference standard on both days. Results All 3D-SSFP sequences were successfully acquired within one breath-hold after GdD and GdT administration. CNR and BMC were significantly (p vs. 23.7 and regression analysis showed a stronger correlation to the reference standard (R2 = 0.92 vs. R2 = 0.71, compared to 3D-SSFP with GdD. Conclusions A single-breath-hold 3D-whole-heart cine SSFP sequence in combination with 32-channel technology and an intravascular contrast agent allows for the accurate and fast assessment of LV function. Trial registration The study was approved by the local

  13. RELAP5-3D Developmental Assessment: Comparison of Versions 4.2.1i and 4.1.3i

    Bayless, Paul D. [Idaho National Lab. (INL), Idaho Falls, ID (United States)


    Figures have been generated comparing the parameters used in the developmental assessment of the RELAP5-3D code using versions 4.2.1i and 4.1.3i. The figures, which are the same as those used in Volume III of the RELAP5-3D code manual, compare calculations using the semi-implicit solution scheme with available experiment data. These figures provide a quick, visual indication of how the code predictions changed between these two code versions and can be used to identify cases in which the assessment judgment may need to be changed in Volume III of the code manual. Changes to the assessment judgments made after reviewing all of the assessment cases are also provided.

  14. RELAP5-3D Developmental Assessment: Comparison of Versions 4.3.4i and 4.2.1i

    Bayless, Paul David [Idaho National Lab. (INL), Idaho Falls, ID (United States)


    Figures have been generated comparing the parameters used in the developmental assessment of the RELAP5-3D code using versions 4.3.4i and 4.2.1i. The figures, which are the same as those used in Volume III of the RELAP5-3D code manual, compare calculations using the semi-implicit solution scheme with available experiment data. These figures provide a quick, visual indication of how the code predictions changed between these two code versions and can be used to identify cases in which the assessment judgment may need to be changed in Volume III of the code manual. Changes to the assessment judgments made after reviewing all of the assessment cases are also provided.

  15. Comparison of the accuracy of voxel based registration and surface based registration for 3D assessment of surgical change following orthognathic surgery.

    Anas Almukhtar

    Full Text Available PURPOSE: Superimposition of two dimensional preoperative and postoperative facial images, including radiographs and photographs, are used to evaluate the surgical changes after orthognathic surgery. Recently, three dimensional (3D imaging has been introduced allowing more accurate analysis of surgical changes. Surface based registration and voxel based registration are commonly used methods for 3D superimposition. The aim of this study was to evaluate and compare the accuracy of the two methods. MATERIALS AND METHODS: Pre-operative and 6 months post-operative cone beam CT scan (CBCT images of 31 patients were randomly selected from the orthognathic patient database at the Dental Hospital and School, University of Glasgow, UK. Voxel based registration was performed on the DICOM images (Digital Imaging Communication in Medicine using Maxilim software (Medicim-Medical Image Computing, Belgium. Surface based registration was performed on the soft and hard tissue 3D models using VRMesh (VirtualGrid, Bellevue City, WA. The accuracy of the superimposition was evaluated by measuring the mean value of the absolute distance between the two 3D image surfaces. The results were statistically analysed using a paired Student t-test, ANOVA with post-hoc Duncan test, a one sample t-test and Pearson correlation coefficient test. RESULTS: The results showed no significant statistical difference between the two superimposition methods (p<0.05. However surface based registration showed a high variability in the mean distances between the corresponding surfaces compared to voxel based registration, especially for soft tissue. Within each method there was a significant difference between superimposition of the soft and hard tissue models. CONCLUSIONS: There were no significant statistical differences between the two registration methods and it was unlikely to have any clinical significance. Voxel based registration was associated with less variability. Registering on

  16. Assessment of a Microsoft Kinect-based 3D scanning system for taking body segment girth measurements: a comparison to ISAK and ISO standards.

    Clarkson, Sean; Wheat, Jon; Heller, Ben; Choppin, Simon


    Use of anthropometric data to infer sporting performance is increasing in popularity, particularly within elite sport programmes. Measurement typically follows standards set by the International Society for the Advancement of Kinanthropometry (ISAK). However, such techniques are time consuming, which reduces their practicality. Schranz et al. recently suggested 3D body scanners could replace current measurement techniques; however, current systems are costly. Recent interest in natural user interaction has led to a range of low-cost depth cameras capable of producing 3D body scans, from which anthropometrics can be calculated. A scanning system comprising 4 depth cameras was used to scan 4 cylinders, representative of the body segments. Girth measurements were calculated from the 3D scans and compared to gold standard measurements. Requirements of a Level 1 ISAK practitioner were met in all 4 cylinders, and ISO standards for scan-derived girth measurements were met in the 2 larger cylinders only. A fixed measurement bias was identified that could be corrected with a simple offset factor. Further work is required to determine comparable performance across a wider range of measurements performed upon living participants. Nevertheless, findings of the study suggest such a system offers many advantages over current techniques, having a range of potential applications.

  17. 3D and beyond

    Fung, Y. C.


    This conference on physiology and function covers a wide range of subjects, including the vasculature and blood flow, the flow of gas, water, and blood in the lung, the neurological structure and function, the modeling, and the motion and mechanics of organs. Many technologies are discussed. I believe that the list would include a robotic photographer, to hold the optical equipment in a precisely controlled way to obtain the images for the user. Why are 3D images needed? They are to achieve certain objectives through measurements of some objects. For example, in order to improve performance in sports or beauty of a person, we measure the form, dimensions, appearance, and movements.

  18. Postoperative Radiotherapy for Prostate Cancer: A Comparison of Four Consensus Guidelines and Dosimetric Evaluation of 3D-CRT Versus Tomotherapy IMRT

    Malone, Shawn, E-mail: [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Croke, Jennifer [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Roustan-Delatour, Nicolas; Belanger, Eric [Department of Pathology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Avruch, Leonard [Department of Radiology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Malone, Colin [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Morash, Christopher [Division of Urology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Kayser, Cathleen; Underhill, Kathryn; Li Yan; Malone, Kyle [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Nyiri, Balazs [Department of Medical Physics, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada); Spaans, Johanna [Division of Radiation Oncology, Ottawa Hospital, University of Ottawa, Ottawa, Ontario (Canada)


    Purpose: Despite the benefits of adjuvant radiotherapy after radical prostatectomy, approximately one-half of patients relapse. Four consensus guidelines have been published (European Organization for Research and Treatment of Cancer, Faculty of Radiation Oncology Genito-Urinary Group, Princess Margaret Hospital, Radiation Therapy Oncology Group) with the aim of standardizing the clinical target volume (CTV) delineation and improve outcomes. To date, no attempt has been made to compare these guidelines in terms of treatment volumes or organ at risk (OAR) irradiation. The extent to which the guideline-derived plans meet the dosimetric constraints of present trials or of the Quantitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC) trial is also unknown. Our study also explored the dosimetric benefits of intensity-modulated radiotherapy (IMRT). Methods and Materials: A total of 20 patients treated with postoperative RT were included. The three-dimensional conformal radiotherapy (3D-CRT) plans were applied to cover the guideline-generated planning target volumes (66 Gy in 33 fractions). Dose-volume histograms (DVHs) were analyzed for CTV/planning target volume coverage and to evaluate OAR irradiation. The OAR DVHs were compared with the constraints proposed in the QUANTEC and Radiotherapy and Androgen Deprivation In Combination After Local Surgery (RADICALS) trials. 3D-CRT plans were compared with the tomotherapy plans for the Radiation Therapy Oncology Group planning target volume to evaluate the advantages of IMRT. Results: The CTV differed significantly between guidelines (p < 0.001). The European Organization for Research and Treatment of Cancer-CTVs were significantly smaller than the other CTVs (p < 0.001). Differences in prostate bed coverage superiorly accounted for the major volumetric differences between the guidelines. Using 3D-CRT, the DVHs rarely met the QUANTEC or RADICALS rectal constraints, independent of the guideline used. The RADICALS

  19. Comparação entre a ecocardiografia 2D e 3D na avaliação do remodelamento reverso após a TRC Comparación entre la ecocardiografía 2D y 3D en la evaluación del remodelado reverso después de la TRC Comparison between 2D and 3D echocardiography in the evaluation of reverse remodeling after CRT

    Viviane Tiemi Hotta


    echocardiography and three-dimensional echocardiography. METHODS: We evaluated 24 patients with HF FCIIIouIV (NYHA, sinus rhythm QRS > 150 ms, during an optimized therapy for HF undergoing CRT. We conducted electrocardiogram (ECG, clinical evaluation, 2D and 3D echocardiography before, three and six months after CRT. The comparison between the techniques was performed using Pearson's correlation (r. Results: At baseline, the correlation between methods was 0.96 for evaluation of LVDV, 0.95 for evaluation of LVSV, 0.87 for LVEF and 0.72 for LV mass. After three months of CRT, the correlation between methods for analysis of LVDV was 0.96, 0.95 for LVSV, 0.95 for LVEF, and 0.77 for LV mass. After six months of CRT, the correlation between 2D and 3D echocardiography for analysis of LVDV was 0.98, 0.91 for LVSV, 0.96 for LVEF, and 0.85 for LV mass. CONCLUSION: This study reported was a reduction of LVDV, LVSV, besides improvement in LVEF after CRT. There was an excellent correlation between the 2D and 3D echocardiography for evaluation of ventricular volumes and LVEF, and a good correlation between methods for evaluation of left ventricular mass before and after CRT.

  20. 3D face modeling, analysis and recognition

    Daoudi, Mohamed; Veltkamp, Remco


    3D Face Modeling, Analysis and Recognition presents methodologies for analyzing shapes of facial surfaces, develops computational tools for analyzing 3D face data, and illustrates them using state-of-the-art applications. The methodologies chosen are based on efficient representations, metrics, comparisons, and classifications of features that are especially relevant in the context of 3D measurements of human faces. These frameworks have a long-term utility in face analysis, taking into account the anticipated improvements in data collection, data storage, processing speeds, and application s

  1. 3D Surgical Simulation

    Cevidanes, Lucia; Tucker, Scott; Styner, Martin; Kim, Hyungmin; Chapuis, Jonas; Reyes, Mauricio; Proffit, William; Turvey, Timothy; Jaskolka, Michael


    This paper discusses the development of methods for computer-aided jaw surgery. Computer-aided jaw surgery allows us to incorporate the high level of precision necessary for transferring virtual plans into the operating room. We also present a complete computer-aided surgery (CAS) system developed in close collaboration with surgeons. Surgery planning and simulation include construction of 3D surface models from Cone-beam CT (CBCT), dynamic cephalometry, semi-automatic mirroring, interactive cutting of bone and bony segment repositioning. A virtual setup can be used to manufacture positioning splints for intra-operative guidance. The system provides further intra-operative assistance with the help of a computer display showing jaw positions and 3D positioning guides updated in real-time during the surgical procedure. The CAS system aids in dealing with complex cases with benefits for the patient, with surgical practice, and for orthodontic finishing. Advanced software tools for diagnosis and treatment planning allow preparation of detailed operative plans, osteotomy repositioning, bone reconstructions, surgical resident training and assessing the difficulties of the surgical procedures prior to the surgery. CAS has the potential to make the elaboration of the surgical plan a more flexible process, increase the level of detail and accuracy of the plan, yield higher operative precision and control, and enhance documentation of cases. Supported by NIDCR DE017727, and DE018962 PMID:20816308


    Ms. Swapnali R. Ghadge


    Full Text Available In today’s ever-shifting media landscape, it can be a complex task to find effective ways to reach your desired audience. As traditional media such as television continue to lose audience share, one venue in particular stands out for its ability to attract highly motivated audiences and for its tremendous growth potential the 3D Internet. The concept of '3D Internet' has recently come into the spotlight in the R&D arena, catching the attention of many people, and leading to a lot of discussions. Basically, one can look into this matter from a few different perspectives: visualization and representation of information, and creation and transportation of information, among others. All of them still constitute research challenges, as no products or services are yet available or foreseen for the near future. Nevertheless, one can try to envisage the directions that can be taken towards achieving this goal. People who take part in virtual worlds stay online longer with a heightened level of interest. To take advantage of that interest, diverse businesses and organizations have claimed an early stake in this fast-growing market. They include technology leaders such as IBM, Microsoft, and Cisco, companies such as BMW, Toyota, Circuit City, Coca Cola, and Calvin Klein, and scores of universities, including Harvard, Stanford and Penn State.

  3. Classification-based comparison of pre-processing methods for interpretation of mass spectrometry generated clinical datasets

    Hoefsloot Huub CJ


    Full Text Available Abstract Background Mass spectrometry is increasingly being used to discover proteins or protein profiles associated with disease. Experimental design of mass-spectrometry studies has come under close scrutiny and the importance of strict protocols for sample collection is now understood. However, the question of how best to process the large quantities of data generated is still unanswered. Main challenges for the analysis are the choice of proper pre-processing and classification methods. While these two issues have been investigated in isolation, we propose to use the classification of patient samples as a clinically relevant benchmark for the evaluation of pre-processing methods. Results Two in-house generated clinical SELDI-TOF MS datasets are used in this study as an example of high throughput mass-spectrometry data. We perform a systematic comparison of two commonly used pre-processing methods as implemented in Ciphergen ProteinChip Software and in the Cromwell package. With respect to reproducibility, Ciphergen and Cromwell pre-processing are largely comparable. We find that the overlap between peaks detected by either Ciphergen ProteinChip Software or Cromwell is large. This is especially the case for the more stringent peak detection settings. Moreover, similarity of the estimated intensities between matched peaks is high. We evaluate the pre-processing methods using five different classification methods. Classification is done in a double cross-validation protocol using repeated random sampling to obtain an unbiased estimate of classification accuracy. No pre-processing method significantly outperforms the other for all peak detection settings evaluated. Conclusion We use classification of patient samples as a clinically relevant benchmark for the evaluation of pre-processing methods. Both pre-processing methods lead to similar classification results on an ovarian cancer and a Gaucher disease dataset. However, the settings for pre

  4. A quantitative comparison of human HT-1080 fibrosarcoma cells and primary human dermal fibroblasts identifies a 3D migration mechanism with properties unique to the transformed phenotype.

    Michael P Schwartz

    Full Text Available Here, we describe an engineering approach to quantitatively compare migration, morphologies, and adhesion for tumorigenic human fibrosarcoma cells (HT-1080s and primary human dermal fibroblasts (hDFs with the aim of identifying distinguishing properties of the transformed phenotype. Relative adhesiveness was quantified using self-assembled monolayer (SAM arrays and proteolytic 3-dimensional (3D migration was investigated using matrix metalloproteinase (MMP-degradable poly(ethylene glycol (PEG hydrogels ("synthetic extracellular matrix" or "synthetic ECM". In synthetic ECM, hDFs were characterized by vinculin-containing features on the tips of protrusions, multipolar morphologies, and organized actomyosin filaments. In contrast, HT-1080s were characterized by diffuse vinculin expression, pronounced β1-integrin on the tips of protrusions, a cortically-organized F-actin cytoskeleton, and quantitatively more rounded morphologies, decreased adhesiveness, and increased directional motility compared to hDFs. Further, HT-1080s were characterized by contractility-dependent motility, pronounced blebbing, and cortical contraction waves or constriction rings, while quantified 3D motility was similar in matrices with a wide range of biochemical and biophysical properties (including collagen despite substantial morphological changes. While HT-1080s were distinct from hDFs for each of the 2D and 3D properties investigated, several features were similar to WM239a melanoma cells, including rounded, proteolytic migration modes, cortical F-actin organization, and prominent uropod-like structures enriched with β1-integrin, F-actin, and melanoma cell adhesion molecule (MCAM/CD146/MUC18. Importantly, many of the features observed for HT-1080s were analogous to cellular changes induced by transformation, including cell rounding, a disorganized F-actin cytoskeleton, altered organization of focal adhesion proteins, and a weakly adherent phenotype. Based on our results

  5. a Comparison among Different Optimization Levels in 3d Multi-Sensor Models. a Test Case in Emergency Context: 2016 Italian Earthquake

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


    In sudden emergency contexts that affect urban centres and built heritage, the latest Geomatics technique solutions must enable the demands of damage documentation, risk assessment, management and data sharing as efficiently as possible, in relation to the danger condition, to the accessibility constraints of areas and to the tight deadlines needs. In recent times, Unmanned Vehicle System (UAV) equipped with cameras are more and more involved in aerial survey and reconnaissance missions, and they are behaving in a very cost-effective way in the direction of 3D documentation and preliminary damage assessment. More and more UAV equipment with low-cost sensors must become, in the future, suitable in every situation of documentation, but above all in damages and uncertainty frameworks. Rapidity in acquisition times and low-cost sensors are challenging marks, and they could be taken into consideration maybe with time spending processing. The paper will analyze and try to classify the information content in 3D aerial and terrestrial models and the importance of metric and non-metric withdrawable information that should be suitable for further uses, as the structural analysis one. The test area is an experience of Team Direct from Politecnico di Torino in centre Italy, where a strong earthquake occurred in August 2016. This study is carried out on a stand-alone damaged building in Pescara del Tronto (AP), with a multi-sensor 3D survey. The aim is to evaluate the contribution of terrestrial and aerial quick documentation by a SLAM based LiDAR and a camera equipped multirotor UAV, for a first reconnaissance inspection and modelling in terms of level of details, metric and non-metric information.

  6. Morphometric Optic Nerve Head Analysis in Glaucoma Patients: A Comparison between the Simultaneous Nonmydriatic Stereoscopic Fundus Camera (Kowa Nonmyd WX3D and the Heidelberg Scanning Laser Ophthalmoscope (HRT III

    Siegfried Mariacher


    Full Text Available Purpose. To investigate the agreement between morphometric optic nerve head parameters assessed with the confocal laser ophthalmoscope HRT III and the stereoscopic fundus camera Kowa nonmyd WX3D retrospectively. Methods. Morphometric optic nerve head parameters of 40 eyes of 40 patients with primary open angle glaucoma were analyzed regarding their vertical cup-to-disc-ratio (CDR. Vertical CDR, disc area, cup volume, rim volume, and maximum cup depth were assessed with both devices by one examiner. Mean bias and limits of agreement (95% CI were obtained using scatter plots and Bland-Altman analysis. Results. Overall vertical CDR comparison between HRT III and Kowa nonmyd WX3D measurements showed a mean difference (limits of agreement of −0.06 (−0.36 to 0.24. For the CDR < 0.5 group (n=24 mean difference in vertical CDR was −0.14 (−0.34 to 0.06 and for the CDR ≥ 0.5 group (n=16 0.06 (−0.21 to 0.34. Conclusion. This study showed a good agreement between Kowa nonmyd WX3D and HRT III with regard to widely used optic nerve head parameters in patients with glaucomatous optic neuropathy. However, data from Kowa nonmyd WX3D exhibited the tendency to measure larger CDR values than HRT III in the group with CDR < 0.5 group and lower CDR values in the group with CDR ≥ 0.5.

  7. Analysis of the behavior and 2D modeling of ferrite inductors with E geometry: comparison with 3D model and real measurements

    Pleite J.


    Full Text Available In this paper we propose and validate by experiment a practical method to compute by simulations the inductance of a ferrite inductor as a function of the current intensity level from the linear to the saturation regions. Our method combines the use of 2D Finite Element Analysis with experimental measurements taken in a laboratory environment. We also present and analyze results of the convergence and computational cost of the 2D and 3D simulations showing the reduction of computational cost when we chose the 2D simulation.

  8. Near-infrared spectro-interferometry of Mira variables and comparisons to 1D dynamic model atmospheres and 3D convection simulations

    Wittkowski, M.; Chiavassa, A.; Freytag, B.; Scholz, M.; Höfner, S.; Karovicova, I.; Whitelock, P. A.


    Aims: We aim at comparing spectro-interferometric observations of Mira variable asymptotic giant branch (AGB) stars with the latest 1D dynamic model atmospheres based on self-excited pulsation models (CODEX models) and with 3D dynamic model atmospheres including pulsation and convection (CO5BOLD models) to better understand the processes that extend the molecular atmosphere to radii where dust can form. Methods: We obtained a total of 20 near-infrared K-band spectro-interferometric snapshot observations of the Mira variables o Cet, R Leo, R Aqr, X Hya, W Vel, and R Cnc with a spectral resolution of about 1500. We compared observed flux and visibility spectra with predictions by CODEX 1D dynamic model atmospheres and with azimuthally averaged intensities based on CO5BOLD 3D dynamic model atmospheres. Results: Our visibility data confirm the presence of spatially extended molecular atmospheres located above the continuum radii with large-scale inhomogeneities or clumps that contribute a few percent of the total flux. The detailed structure of the inhomogeneities or clumps show a variability on time scales of 3 months and above. Both modeling attempts provided satisfactory fits to our data. In particular, they are both consistent with the observed decrease in the visibility function at molecular bands of water vapor and CO, indicating a spatially extended molecular atmosphere. Observational variability phases are mostly consistent with those of the best-fit CODEX models, except for near-maximum phases, where data are better described by near-minimum models. Rosseland angular diameters derived from the model fits are broadly consistent between those based on the 1D and the 3D models and with earlier observations. We derived fundamental parameters including absolute radii, effective temperatures, and luminosities for our sources. Conclusions: Our results provide a first observational support for theoretical results that shocks induced by convection and pulsation in the

  9. WE-AB-BRA-01: 3D-2D Image Registration for Target Localization in Spine Surgery: Comparison of Similarity Metrics Against Robustness to Content Mismatch

    De Silva, T; Ketcha, M; Siewerdsen, J H [Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD (United States); Uneri, A; Reaungamornrat, S [Department of Computer Science, Johns Hopkins University, Baltimore, MD (United States); Vogt, S; Kleinszig, G [Siemens Healthcare XP Division, Erlangen, DE (Germany); Lo, S F; Wolinsky, J P; Gokaslan, Z L [Department of Neurosurgery, The Johns Hopkins Hospital, Baltimore, MD (United States); Aygun, N [Department of Raiology and Radiological Sciences, The Johns Hopkins Hospital, Baltimore, MD (United States)


    Purpose: In image-guided spine surgery, mapping 3D preoperative images to 2D intraoperative images via 3D-2D registration can provide valuable assistance in target localization. However, the presence of surgical instrumentation, hardware implants, and soft-tissue resection/displacement causes mismatches in image content, confounding existing registration methods. Manual/semi-automatic methods to mask such extraneous content is time consuming, user-dependent, error prone, and disruptive to clinical workflow. We developed and evaluated 2 novel similarity metrics within a robust registration framework to overcome such challenges in target localization. Methods: An IRB-approved retrospective study in 19 spine surgery patients included 19 preoperative 3D CT images and 50 intraoperative mobile radiographs in cervical, thoracic, and lumbar spine regions. A neuroradiologist provided truth definition of vertebral positions in CT and radiography. 3D-2D registration was performed using the CMA-ES optimizer with 4 gradient-based image similarity metrics: (1) gradient information (GI); (2) gradient correlation (GC); (3) a novel variant referred to as gradient orientation (GO); and (4) a second variant referred to as truncated gradient correlation (TGC). Registration accuracy was evaluated in terms of the projection distance error (PDE) of the vertebral levels. Results: Conventional similarity metrics were susceptible to gross registration error and failure modes associated with the presence of surgical instrumentation: for GI, the median PDE and interquartile range was 33.0±43.6 mm; similarly for GC, PDE = 23.0±92.6 mm respectively. The robust metrics GO and TGC, on the other hand, demonstrated major improvement in PDE (7.6 ±9.4 mm and 8.1± 18.1 mm, respectively) and elimination of gross failure modes. Conclusion: The proposed GO and TGC similarity measures improve registration accuracy and robustness to gross failure in the presence of strong image content mismatch. Such

  10. KPG Index versus OPG Measurements: A Comparison between 3D and 2D Methods in Predicting Treatment Duration and Difficulty Level for Patients with Impacted Maxillary Canines

    Domenico Dalessandri


    Full Text Available Aim. The aim of this study was to test the agreement between orthopantomography (OPG based 2D measurements and the KPG index, a new index based on 3D Cone Beam Computed Tomography (CBCT images, in predicting orthodontic treatment duration and difficulty level of impacted maxillary canines. Materials and Methods. OPG and CBCT images of 105 impacted canines were independently scored by three orthodontists at t0 and after 1 month (t1, using the KPG index and the following 2D methods: distance from cusp tip and occlusal plane, cusp tip position in relation to the lateral incisor, and canine inclination. Pearson’s coefficients were used to evaluate the degree of agreement and the χ2 with Yates correction test was used to assess the independence between them. Results. Inter- and intrarater reliability were higher with KPG compared to 2D methods. Pearson’s coefficients showed a statistically significant association between all the indexes, while the χ2 with Yates correction test resulted in a statistically significant rejection of independency only for one 2D index. Conclusions. 2D indexes for predicting impacted maxillary canines treatment duration and difficulty sometimes are discordant; a 3D index like the KPG index could be useful in solving these conflicts.

  11. Comparison of UAV-Enabled Photogrammetry-Based 3D Point Clouds and Interpolated DSMs of Sloping Terrain for Rockfall Hazard Analysis

    Manousakis, J.; Zekkos, D.; Saroglou, F.; Clark, M.


    UAVs are expected to be particularly valuable to define topography for natural slopes that may be prone to geological hazards, such as landslides or rockfalls. UAV-enabled imagery and aerial mapping can lead to fast and accurate qualitative and quantitative results for photo documentation as well as basemap 3D analysis that can be used for geotechnical stability analyses. In this contribution, the case study of a rockfall near Ponti village that was triggered during the November 17th 2015 Mw 6.5 earthquake in Lefkada, Greece is presented with a focus on feature recognition and 3D terrain model development for use in rockfall hazard analysis. A significant advantage of the UAV was the ability to identify from aerial views the rockfall trajectory along the terrain, the accuracy of which is crucial to subsequent geotechnical back-analysis. Fast static GPS control points were measured for optimizing internal and external camera parameters and model georeferencing. Emphasis is given on an assessment of the error associated with the basemap when fewer and poorly distributed ground control points are available. Results indicate that spatial distribution and image occurrences of control points throughout the mapped area and image block is essential in order to produce accurate geospatial data with minimum distortions.

  12. Comparison between Thin-Slice 3-D Volumetric Ultrasound and Conventional Ultrasound in the Differentiation of Benign and Malignant Thyroid Lesions.

    Li, Wen-Bo; Zhang, Bo; Zhu, Qing-Li; Jiang, Yu-Xin; Sun, Jian; Yang, Meng; Li, Jian-Chu


    We explored the efficacy of thin-slice volumetric 3-D ultrasound (3-DUS) in distinguishing between benign and malignant thyroid nodules. A total of 103 thyroid nodules were evaluated prospectively using 3-D gray-scale ultrasonography. The shape, margin, halo and potential capsular invasion of the nodules were compared with the findings of conventional 2-D ultrasound (2-DUS). Of the 103 thyroid nodules, there were 50 pathologically confirmed benign lesions and 53 malignant lesions (51.5%). Shape irregularity, ill-defined margins and capsular invasion provided sensitivities of 90.0%, 47.2% and 39.6% and specificities of 88.0%, 84.0% and 100%, respectively, for the malignant lesions. The diagnosis of thyroid cancer was improved in 3-DUS compared with 2-DUS, with a sensitivity of 88.7%, specificity of 90.0%, positive predictive value of 90.4%, negative predictive value of 88.2% and accuracy of 89.3%. The sensitivity of detection for lesions with capsular invasion increased to 39.6% with 3-DUS, more than twice that of 2-DUS. Three-dimensional US is highly accurate in diagnosing thyroid nodules, particularly those with capsular invasion.

  13. Comparison between 3D volumetric rendering and multiplanar slices on the reliability of linear measurements on CBCT images: an in vitro study

    Thais Maria Freire FERNANDES


    Full Text Available OBJECTIVE: The purpose of this study was to determine the accuracy and reliability of two methods of measurements of linear distances (multiplanar 2D and tridimensional reconstruction 3D obtained from cone-beam computed tomography (CBCT with different voxel sizes. MATERIAL AND METHODS: Ten dry human mandibles were scanned at voxel sizes of 0.2 and 0.4 mm. Craniometric anatomical landmarks were identified twice by two independent operators on the multiplanar reconstructed and on volume rendering images that were generated by the software Dolphin®. Subsequently, physical measurements were performed using a digital caliper. Analysis of variance (ANOVA, intraclass correlation coefficient (ICC and Bland-Altman were used for evaluating accuracy and reliability (p<0.05. RESULTS: Excellent intraobserver reliability and good to high precision interobserver reliability values were found for linear measurements from CBCT 3D and multiplanar images. Measurements performed on multiplanar reconstructed images were more accurate than measurements in volume rendering compared with the gold standard. No statistically significant difference was found between voxel protocols, independently of the measurement method. CONCLUSIONS: Linear measurements on multiplanar images of 0.2 and 0.4 voxel are reliable and accurate when compared with direct caliper measurements. Caution should be taken in the volume rendering measurements, because the measurements were reliable, but not accurate for all variables. An increased voxel resolution did not result in greater accuracy of mandible measurements and would potentially provide increased patient radiation exposure.

  14. Comparative visualization for parameter studies of dataset series.

    Malik, Muhammad Muddassir; Heinzl, Christoph; Eduard Gröller, M


    This paper proposes comparison and visualization techniques to carry out parameter studies for the special application area of dimensional measurement using 3D X-ray computed tomography (3DCT). A dataset series is generated by scanning a specimen multiple times by varying parameters of an industrial 3DCT device. A high-resolution series is explored using our planar-reformatting-based visualization system. We present a novel multi-image view and an edge explorer for comparing and visualizing gray values and edges of several datasets simultaneously. Visualization results and quantitative data are displayed side by side. Our technique is scalable and generic. It can be effective in various application areas like parameter studies of imaging modalities and dataset artifact detection. For fast data retrieval and convenient usability, we use bricking of the datasets and efficient data structures. We evaluate the applicability of the proposed techniques in collaboration with our company partners.

  15. Comparison of 2D and 3D Imaging and Treatment Planning for Postoperative Vaginal Apex High-Dose Rate Brachytherapy for Endometrial Cancer

    Russo, James K. [Department of Radiation Oncology, Hollings Cancer Center, Medical University of South Carolina, Charleston, South Carolina (United States); Armeson, Kent E. [Division of Biostatistics and Epidemiology, Hollings Cancer Center, Medical University of South Carolina, Charleston, South Carolina (United States); Richardson, Susan, E-mail: [Department of Radiation Oncology, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri (United States)


    Purpose: To evaluate bladder and rectal doses using two-dimensional (2D) and 3D treatment planning for vaginal cuff high-dose rate (HDR) in endometrial cancer. Methods and Materials: Ninety-one consecutive patients treated between 2000 and 2007 were evaluated. Seventy-one and 20 patients underwent 2D and 3D planning, respectively. Each patient received six fractions prescribed at 0.5 cm to the superior 3 cm of the vagina. International Commission on Radiation Units and Measurements (ICRU) doses were calculated for 2D patients. Maximum and 2-cc doses were calculated for 3D patients. Organ doses were normalized to prescription dose. Results: Bladder maximum doses were 178% of ICRU doses (p < 0.0001). Two-cubic centimeter doses were no different than ICRU doses (p = 0.22). Two-cubic centimeter doses were 59% of maximum doses (p < 0.0001). Rectal maximum doses were 137% of ICRU doses (p < 0.0001). Two-cubic centimeter doses were 87% of ICRU doses (p < 0.0001). Two-cubic centimeter doses were 64% of maximum doses (p < 0.0001). Using the first 1, 2, 3, 4 or 5 fractions, we predicted the final bladder dose to within 10% for 44%, 59%, 83%, 82%, and 89% of patients by using the ICRU dose, and for 45%, 55%, 80%, 85%, and 85% of patients by using the maximum dose, and for 37%, 68%, 79%, 79%, and 84% of patients by using the 2-cc dose. Using the first 1, 2, 3, 4 or 5 fractions, we predicted the final rectal dose to within 10% for 100%, 100%, 100%, 100%, and 100% of patients by using the ICRU dose, and for 60%, 65%, 70%, 75%, and 75% of patients by using the maximum dose, and for 68%, 95%, 84%, 84%, and 84% of patients by using the 2-cc dose. Conclusions: Doses to organs at risk vary depending on the calculation method. In some cases, final dose accuracy appears to plateau after the third fraction, indicating that simulation and planning may not be necessary in all fractions. A clinically relevant level of accuracy should be determined and further research conducted to address

  16. A comparison of 4D time-resolved MRA with keyhole and 3D time-of-flight MRA at 3.0 T for the evaluation of cerebral aneurysms

    Wu Qian


    Full Text Available Abstract Background A subarachnoid hemorrhage (SAH due to the rupture of a cerebral aneurysm (CA is a devastating event associated with high rates of mortality. Magnetic resonance angiography (MRA, as a noninvasive technique, is typically used initially. The object of our study is to evaluate the feasibility of 4D time-resolved MRA with keyhole (4D-TRAK for the diagnostic accuracy and reliability of the detection and characterization of cerebral aneurysms (CAs, with a comparison of 3D time-of-flight MRA (3D-TOF-MRA by using DSA as a reference. Methods 3D-TOF-MRA, 4D-TRAK and 3D-DSA were performed sequentially in 52 patients with suspected CAs. 4D-TRAK was acquired using a combination of sensitivity encoding (SENSE and CE timing robust angiography (CENTRA k-space sampling techniques at a contrast dose of 10 ml at 3 T. Accuracy, sensitivity, specificity of 4D-TRAK and 3D-TOF-MRA were calculated and compared for the detection of CAs on patient-based and aneurysm-based evaluation using 3D-DSA as a reference. Results The overall image quality of 4D-TRAK with a contrast dose of 10 ml was in the diagnostic range but still cannot be compared with that of 3D-TOF-MRA. In 52 patients with suspected CAs, fifty-eight CAs were confirmed on 3D-DSA finally. Fifty-one (with 2 false-positives and 9 false-negatives and 58 (with 1 false-positive and 1 false-negative CAs were visualized on 4D-TRAK and 3D-TOF-MRA, respectively. Accuracy, sensitivity and specificity on patient-based evaluation of 4D-TRAK and 3D-TOF-MRA were 92.31%, 93.33%, 85.71% and 98.08%, 100%, 85.71%, respectively, and 74.07%, 75.00%, 66.67% and 96.30%, 95.83%, 100% on aneurysm-based evaluation in patients with multiple CAs, respectively. Subgroup analysis revealed that for 19 very small CAs (maximal diameter Conclusion 4D-TRAK at a lower contrast dose of 10 ml with a combination of SENSE and CENTRA at 3 T could provide similar diagnostic accuracy rate for CAs with maximal diameter ≥ 3 mm

  17. Comparison of dosimeter response: ionization chamber, TLD, and Gafchromic EBT2 film in 3D-CRT, IMRT, and SBRT techniques for lung cancer

    Fitriandini, A.; Wibowo, W. E.; Pawiro, S. A.


    This research was conducted by measuring point dose in the target area (lungs), heart, and spine using four dosimeters (PTW N30013, Exradin A16, TLD, and the Gafchromic EBT2 film). The measurement was performed in CIRS 002LFC thorax phantom. The main objective of this study was to compare the dosimetry of those different systems. Dose measurements performed only in a single fraction of irradiation. The measurements result shown that TLD has the least accuracy and precision. As the effect of volume averaging, ionization chamber reaches the discrepancy value up to -13.30% in the target area. EBT2 film has discrepancy value of <1% in the 3D-CRT and IMRT techniques. This dosimeter is proposed to be an appropriate alternative dosimeter to be used at point dose verification.

  18. Comparison of open and closed U-Pu equilibrium fuel cycles for Generation-IV fast reactors with the EQL3D procedure

    Krepel, Jiri, E-mail: [Laboratory for Reactor Physics and Systems Behaviour, Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Pelloni, Sandro; Mikityuk, Konstantin [Laboratory for Reactor Physics and Systems Behaviour, Paul Scherrer Institut, 5232 Villigen PSI (Switzerland)


    Highlights: Black-Right-Pointing-Pointer We analyze open and closed fuel cycle of GFR, SFR, and LFR cores by means of ERANOS based EQL3D procedure. Black-Right-Pointing-Pointer Equilibrium of open and closed fuel cycles were compared in terms of their performance and safety parameters. Black-Right-Pointing-Pointer All three cores act in equilibrium closed cycle as iso-breeder and have similar fuel composition. Black-Right-Pointing-Pointer In spite of the same fuel composition the Dopper constants and void reactivities strongly differ between the cores. Black-Right-Pointing-Pointer All three systems seem capable, from neutronics point of view, for the fuel cycle closure. - Abstract: The advanced fast reactors of the fourth generation should enable an indirect burning of poorly fissile {sup 238}U through {sup 239}Pu breeding and recycling of the actinides from their own spent fuel. The recycling or actually the fuel cycle closure can significantly reduce the amount of long-lived radioactive waste and the {sup 238}U burning can multiply the sustainability of the uranium fueled reactors. Regular periodic operation with the fuel recycling converges to an equilibrium cycle. To enable its simulation a numerical tool named equilibrium fuel cycle procedure for fast reactors (EQL3D) was developed in the FAST group of LRS at Paul Scherrer Institut. The procedure is based on the ERANOS code and can be used to yield the description of two basic situations: the equilibrium of an open fuel cycle and the equilibrium of a closed fuel cycle. The goals of the present study are (i) to apply EQL3D to the Gas-cooled Fast Reactor (GFR), Sodium-cooled Fast Reactor (SFR), and Lead-cooled Fast Reactor (LFR), (ii) to simulate and confirm the GFR, SFR, and LFR neutronics capability for closed fuel cycle, and (iii) to evaluate and compare the equilibrium cycle safety and performance parameters. The EQL3D capability enables to characterize the equilibrium cycle for complex reloading patterns

  19. Comparison of the transcriptomic profile of hepatic human induced pluripotent stem like cells cultured in plates and in a 3D microscale dynamic environment.

    Leclerc, Eric; Kimura, Keiichi; Shinohara, Marie; Danoy, Mathieu; Le Gall, Morgane; Kido, Taketomo; Miyajima, Atsushi; Fujii, Teruo; Sakai, Yasuyuki


    We have compared the transcriptomic profiles of human induced pluripotent stem cells after their differentiation in hepatocytes like cells in plates and microfluidic biochips. The biochips provided a 3D and dynamic support during the cell differentiation when compared to the 2D static cultures in plates. The microarray have demonstrated the up regulation of important pathway related to liver development and maturation during the culture in biochips. Furthermore, the results of the transcriptomic profile, coupled with immunostaining, and RTqPCR analysis have shown typical biomarkers illustrating the presence of responders of biliary like cells, hepatocytes like cells, and endothelial like cells. However, the overall tissue still presented characteristic of immature and foetal patterns. Nevertheless, the biochip culture provided a specific micro-environment in which a complex multicellular differentiation toward liver could be oriented.

  20. Comparison of a 3-D multi-group SN particle transport code with Monte Carlo for intracavitary brachytherapy of the cervix uteri.

    Gifford, Kent A; Wareing, Todd A; Failla, Gregory; Horton, John L; Eifel, Patricia J; Mourtada, Firas


    A patient dose distribution was calculated by a 3D multi-group S N particle transport code for intracavitary brachytherapy of the cervix uteri and compared to previously published Monte Carlo results. A Cs-137 LDR intracavitary brachytherapy CT data set was chosen from our clinical database. MCNPX version 2.5.c, was used to calculate the dose distribution. A 3D multi-group S N particle transport code, Attila version 6.1.1 was used to simulate the same patient. Each patient applicator was built in SolidWorks, a mechanical design package, and then assembled with a coordinate transformation and rotation for the patient. The SolidWorks exported applicator geometry was imported into Attila for calculation. Dose matrices were overlaid on the patient CT data set. Dose volume histograms and point doses were compared. The MCNPX calculation required 14.8 hours, whereas the Attila calculation required 22.2 minutes on a 1.8 GHz AMD Opteron CPU. Agreement between Attila and MCNPX dose calculations at the ICRU 38 points was within +/- 3%. Calculated doses to the 2 cc and 5 cc volumes of highest dose differed by not more than +/- 1.1% between the two codes. Dose and DVH overlays agreed well qualitatively. Attila can calculate dose accurately and efficiently for this Cs-137 CT-based patient geometry. Our data showed that a three-group cross-section set is adequate for Cs-137 computations. Future work is aimed at implementing an optimized version of Attila for radiotherapy calculations.

  1. Validity of Intraoral Scans Compared with Plaster Models: An In-Vivo Comparison of Dental Measurements and 3D Surface Analysis.

    Fan Zhang

    Full Text Available Dental measurements have been commonly taken from plaster dental models obtained from alginate impressions can. Through the use of an intraoral scanner, digital impressions now acquire the information directly from the mouth. The purpose of this study was to determine the validity of the intraoral scans compared to plaster models.Two types of dental models (intraoral scan and plaster model of 20 subjects were included in this study. The subjects had impressions taken of their teeth and made as plaster model. In addition, their mouths were scanned with the intraoral scanner and the scans were converted into digital models. Eight transverse and 16 anteroposterior measurements, 24 tooth heights and widths were recorded on the plaster models with a digital caliper and on the intraoral scan with 3D reverse engineering software. For 3D surface analysis, the two models were superimposed by using best-fit algorithm. The average differences between the two models at all points on the surfaces were computed. Paired t-test and Bland-Altman plot were used to determine the validity of measurements from the intraoral scan compared to those from the plaster model.There were no significant differences between the plaster models and intraoral scans, except for one measurement of lower intermolar width. The Bland-Altman plots of all measurements showed that differences between the two models were within the limits of agreement. The average surface difference between the two models was within 0.10 mm.The results of the present study indicate that the intraoral scans are clinically acceptable for diagnosis and treatment planning in dentistry and can be used in place of plaster models.

  2. 3D printing for dummies

    Hausman, Kalani Kirk


    Get started printing out 3D objects quickly and inexpensively! 3D printing is no longer just a figment of your imagination. This remarkable technology is coming to the masses with the growing availability of 3D printers. 3D printers create 3-dimensional layered models and they allow users to create prototypes that use multiple materials and colors.  This friendly-but-straightforward guide examines each type of 3D printing technology available today and gives artists, entrepreneurs, engineers, and hobbyists insight into the amazing things 3D printing has to offer. You'll discover methods for

  3. Intraoral 3D scanner

    Kühmstedt, Peter; Bräuer-Burchardt, Christian; Munkelt, Christoph; Heinze, Matthias; Palme, Martin; Schmidt, Ingo; Hintersehr, Josef; Notni, Gunther


    Here a new set-up of a 3D-scanning system for CAD/CAM in dental industry is proposed. The system is designed for direct scanning of the dental preparations within the mouth. The measuring process is based on phase correlation technique in combination with fast fringe projection in a stereo arrangement. The novelty in the approach is characterized by the following features: A phase correlation between the phase values of the images of two cameras is used for the co-ordinate calculation. This works contrary to the usage of only phase values (phasogrammetry) or classical triangulation (phase values and camera image co-ordinate values) for the determination of the co-ordinates. The main advantage of the method is that the absolute value of the phase at each point does not directly determine the coordinate. Thus errors in the determination of the co-ordinates are prevented. Furthermore, using the epipolar geometry of the stereo-like arrangement the phase unwrapping problem of fringe analysis can be solved. The endoscope like measurement system contains one projection and two camera channels for illumination and observation of the object, respectively. The new system has a measurement field of nearly 25mm × 15mm. The user can measure two or three teeth at one time. So the system can by used for scanning of single tooth up to bridges preparations. In the paper the first realization of the intraoral scanner is described.

  4. Martian terrain - 3D


    This area of terrain near the Sagan Memorial Station was taken on Sol 3 by the Imager for Mars Pathfinder (IMP). 3D glasses are necessary to identify surface detail.The IMP is a stereo imaging system with color capability provided by 24 selectable filters -- twelve filters per 'eye.' It stands 1.8 meters above the Martian surface, and has a resolution of two millimeters at a range of two meters.Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.Click below to see the left and right views individually. [figure removed for brevity, see original site] Left [figure removed for brevity, see original site] Right

  5. Comparison of publically available Moho depth and crustal thickness grids with newly derived grids by 3D gravity inversion for the High Arctic region.

    Lebedeva-Ivanova, Nina; Gaina, Carmen; Minakov, Alexander; Kashubin, Sergey


    We derived Moho depth and crustal thickness for the High Arctic region by 3D forward and inverse gravity modelling method in the spectral domain (Minakov et al. 2012) using lithosphere thermal gravity anomaly correction (Alvey et al., 2008); a vertical density variation for the sedimentary layer and lateral crustal variation density. Recently updated grids of bathymetry (Jakobsson et al., 2012), gravity anomaly (Gaina et al, 2011) and dynamic topography (Spasojevic & Gurnis, 2012) were used as input data for the algorithm. TeMAr sedimentary thickness grid (Petrov et al., 2013) was modified according to the most recently published seismic data, and was re-gridded and utilized as input data. Other input parameters for the algorithm were calibrated using seismic crustal scale profiles. The results are numerically compared with publically available grids of the Moho depth and crustal thickness for the High Arctic region (CRUST 1 and GEMMA global grids; the deep Arctic Ocean grids by Glebovsky et al., 2013) and seismic crustal scale profiles. The global grids provide coarser resolution of 0.5-1.0 geographic degrees and not focused on the High Arctic region. Our grids better capture all main features of the region and show smaller error in relation to the seismic crustal profiles compare to CRUST 1 and GEMMA grids. Results of 3D gravity modelling by Glebovsky et al. (2013) with separated geostructures approach show also good fit with seismic profiles; however these grids cover the deep part of the Arctic Ocean only. Alvey A, Gaina C, Kusznir NJ, Torsvik TH (2008). Integrated crustal thickness mapping and plate recon-structions for the high Arctic. Earth Planet Sci Lett 274:310-321. Gaina C, Werner SC, Saltus R, Maus S (2011). Circum-Arctic mapping project: new magnetic and gravity anomaly maps of the Arctic. Geol Soc Lond Mem 35, 39-48. Glebovsky V.Yu., Astafurova E.G., Chernykh A.A., Korneva M.A., Kaminsky V.D., Poselov V.A. (2013). Thickness of the Earth's crust in the

  6. Comparison of standard 4-row versus 6-row 3-D linear cutter stapler in creation of gastrointestinal system anastomoses: a prospective randomized trial

    Sozutek, Alper; Colak, Tahsin; Dag, Ahmet; Olmez, Tolga


    OBJECTIVE: This prospective study was conducted to compare the clinical outcomes of a 6-row 3-D linear cutter with the standard 4-row linear cutter in patients who underwent elective gastrointestinal surgery anastomosis. METHOD: Patients who underwent elective open gastrointestinal surgery that included stapled anastomosis using a linear cutter (Proximate®, Ethicon Endo-Surgery, Cincinnati, OH) between January 2011 and May 2011 were included in the study. The patients were randomly assigned to two groups according to the linear cutter that was used in the surgery: the standard 4-row cutter (the S group) or the new 6-row cutter (the N group). The groups were compared based on the patient demographic data, the laboratory parameters, the preoperative diagnosis, the surgery performed, the operation time, intra- or postoperative complications, the time to oral tolerance and the length of the hospital stay. RESULTS: The S group included 11 male and nine female patients with a mean age of 65±12 (35-84) years, while the N group included 13 male and eight female patients with a mean age of 62±11 (46-79) years (p = 0.448, p = 0.443, respectively). Anastomotic line bleeding was observed in eight (40%) patients in the S group and in one (4.7%) patient in the N group (p = 0.006). Dehiscence of the anastomosis line was observed in two (10%) patients in the S group and none in the N group (p = 0.131). Anastomotic leakage developed in three (15%) patients in the S group and in one (4.7%) patient in the N group (p = 0.269). The mean hospital stay was 12.65±6.1 days in the S group and 9.52±2.9 days in the N group (p = 0.043). CONCLUSION: The 6-row 3-D linear cutter is a safe and easily applied instrument that can be used to create anastomoses in gastrointestinal surgery. The new stapler provides some usage benefits and is also superior to the standard linear cutter with regard to anastomotic line bleeding. PMID:23018300

  7. The Galicia 3D experiment: an Introduction.

    Reston, Timothy; Martinez Loriente, Sara; Holroyd, Luke; Merry, Tobias; Sawyer, Dale; Morgan, Julia; Jordan, Brian; Tesi Sanjurjo, Mari; Alexanian, Ara; Shillington, Donna; Gibson, James; Minshull, Tim; Karplus, Marianne; Bayracki, Gaye; Davy, Richard; Klaeschen, Dirk; Papenberg, Cord; Ranero, Cesar; Perez-Gussinye, Marta; Martinez, Miguel


    In June and July 2013, scientists from 8 institutions took part in the Galicia 3D seismic experiment, the first ever crustal -scale academic 3D MCS survey over a rifted margin. The aim was to determine the 3D structure of a critical portion of the west Galicia rifted margin. At this margin, well-defined tilted fault blocks, bound by west-dipping faults and capped by synrift sediments are underlain by a bright reflection, undulating on time sections, termed the S reflector and thought to represent a major detachment fault of some kind. Moving west, the crust thins to zero thickness and mantle is unroofed, as evidence by the "Peridotite Ridge" first reported at this margin, but since observed at many other magma-poor margins. By imaging such a margin in detail, the experiment aimed to resolve the processes controlling crustal thinning and mantle unroofing at a type example magma poor margin. The experiment set out to collect several key datasets: a 3D seismic reflection volume measuring ~20x64km and extending down to ~14s TWT, a 3D ocean bottom seismometer dataset suitable for full wavefield inversion (the recording of the complete 3D seismic shots by 70 ocean bottom instruments), the "mirror imaging" of the crust using the same grid of OBS, a single 2D combined reflection/refraction profile extending to the west to determine the transition from unroofed mantle to true oceanic crust, and the seismic imaging of the water column, calibrated by regular deployment of XBTs to measure the temperature structure of the water column. We collected 1280 km2 of seismic reflection data, consisting of 136533 shots recorded on 1920 channels, producing 260 million seismic traces, each ~ 14s long. This adds up to ~ 8 terabytes of data, representing, we believe, the largest ever academic 3D MCS survey in terms of both the area covered and the volume of data. The OBS deployment was the largest ever within an academic 3D survey.

  8. 3D Printing an Octohedron

    Aboufadel, Edward F.


    The purpose of this short paper is to describe a project to manufacture a regular octohedron on a 3D printer. We assume that the reader is familiar with the basics of 3D printing. In the project, we use fundamental ideas to calculate the vertices and faces of an octohedron. Then, we utilize the OPENSCAD program to create a virtual 3D model and an STereoLithography (.stl) file that can be used by a 3D printer.

  9. Salient Local 3D Features for 3D Shape Retrieval

    Godil, Afzal


    In this paper we describe a new formulation for the 3D salient local features based on the voxel grid inspired by the Scale Invariant Feature Transform (SIFT). We use it to identify the salient keypoints (invariant points) on a 3D voxelized model and calculate invariant 3D local feature descriptors at these keypoints. We then use the bag of words approach on the 3D local features to represent the 3D models for shape retrieval. The advantages of the method are that it can be applied to rigid as well as to articulated and deformable 3D models. Finally, this approach is applied for 3D Shape Retrieval on the McGill articulated shape benchmark and then the retrieval results are presented and compared to other methods.

  10. Near-infrared spectro-interferometry of Mira variables and comparisons to 1D dynamic model atmospheres and 3D convection simulations

    Wittkowski, M; Freytag, B; Scholz, M; Hoefner, S; Karovicova, I; Whitelock, P A


    We obtained a total of 20 near-infrared K-band spectro-interferometric snapshot observations of the Mira variables o Cet, R Leo, R Aqr, X Hya, W Vel, and R Cnc with a spectral resolution of about 1500. We compared observed flux and visibility spectra with predictions by CODEX 1D dynamic model atmospheres and with azimuthally averaged intensities based on CO5BOLD 3D dynamic model atmospheres including convection. Our visibility data confirm the presence of spatially extended molecular atmospheres located above the continuum radii with large-scale inhomogeneities or clumps that contribute a few percent of the total flux. The detailed structure of the inhomogeneities or clumps show a variability on time scales of 3 months and above. Both modeling attempts provided satisfactory fits to our data. In particular, they are both consistent with the observed decrease in the visibility function at molecular bands of water vapor and CO, indicating a spatially extended molecular atmosphere. Observational variability phase...

  11. Comparison of DP3 Signals Evoked by Comfortable 3D Images and 2D Images — an Event-Related Potential Study using an Oddball Task

    Ye, Peng; Wu, Xiang; Gao, Dingguo; Liang, Haowen; Wang, Jiahui; Deng, Shaozhi; Xu, Ningsheng; She, Juncong; Chen, Jun


    The horizontal binocular disparity is a critical factor for the visual fatigue induced by watching stereoscopic TVs. Stereoscopic images that possess the disparity within the ‘comfort zones’ and remain still in the depth direction are considered comfortable to the viewers as 2D images. However, the difference in brain activities between processing such comfortable stereoscopic images and 2D images is still less studied. The DP3 (differential P3) signal refers to an event-related potential (ERP) component indicating attentional processes, which is typically evoked by odd target stimuli among standard stimuli in an oddball task. The present study found that the DP3 signal elicited by the comfortable 3D images exhibits the delayed peak latency and enhanced peak amplitude over the anterior and central scalp regions compared to the 2D images. The finding suggests that compared to the processing of the 2D images, more attentional resources are involved in the processing of the stereoscopic images even though they are subjectively comfortable. PMID:28225044

  12. What causes the large extensions of red-supergiant atmospheres? Comparisons of interferometric observations with 1-D hydrostatic, 3-D convection, and 1-D pulsating model atmospheres

    Arroyo-Torres, B; Chiavassa, A; Scholz, M; Freytag, B; Marcaide, J M; Hauschildt, P H; Wood, P R; Abellan, F J


    We present the atmospheric structure and the fundamental parameters of three red supergiants, increasing the sample of RSGs observed by near-infrared spectro-interferometry. Additionally, we test possible mechanisms that may explain the large observed atmospheric extensions of RSGs. We carried out spectro-interferometric observations of 3 RSGs in the near-infrared K-band with the VLTI/AMBER instrument at medium spectral resolution. To comprehend the extended atmospheres, we compared our observational results to predictions by available hydrostatic PHOENIX, available 3-D convection, and new 1-D self-excited pulsation models of RSGs. Our near-infrared flux spectra are well reproduced by the PHOENIX model atmospheres. The continuum visibility values are consistent with a limb-darkened disk as predicted by the PHOENIX models, allowing us to determine the angular diameter and the fundamental parameters of our sources. Nonetheless, in the case of V602 Car and HD 95686, the PHOENIX model visibilities do not predict ...

  13. PB3D: A new code for edge 3-D ideal linear peeling-ballooning stability

    Weyens, T.; Sánchez, R.; Huijsmans, G.; Loarte, A.; García, L.


    A new numerical code PB3D (Peeling-Ballooning in 3-D) is presented. It implements and solves the intermediate-to-high-n ideal linear magnetohydrodynamic stability theory extended to full edge 3-D magnetic toroidal configurations in previous work [1]. The features that make PB3D unique are the assumptions on the perturbation structure through intermediate-to-high mode numbers n in general 3-D configurations, while allowing for displacement of the plasma edge. This makes PB3D capable of very efficient calculations of the full 3-D stability for the output of multiple equilibrium codes. As first verification, it is checked that results from the stability code MISHKA [2], which considers axisymmetric equilibrium configurations, are accurately reproduced, and these are then successfully extended to 3-D configurations, through comparison with COBRA [3], as well as using checks on physical consistency. The non-intuitive 3-D results presented serve as a tentative first proof of the capabilities of the code.

  14. 3D movement correction of CT brain perfusion image data of patients with acute ischemic stroke

    Fahmi, Fahmi [Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam (Netherlands); University of Sumatera Utara, Department of Electrical Engineering, Medan (Indonesia); Marquering, Henk A.; Streekstra, Geert J. [Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam (Netherlands); Academic Medical Center, Department of Radiology, Amsterdam (Netherlands); Borst, Jordi; Beenen, Ludo F.M.; Majoie, Charles B.L. [Academic Medical Center, Department of Radiology, Amsterdam (Netherlands); Niesten, Joris M.; Velthuis, Birgitta K. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); VanBavel, Ed [Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam (Netherlands); Collaboration: on behalf of the DUST study


    Head movement during CT brain perfusion (CTP) acquisition can deteriorate the accuracy of CTP analysis. Most CTP software packages can only correct in-plane movement and are limited to small ranges. The purpose of this study is to validate a novel 3D correction method for head movement during CTP acquisition. Thirty-five CTP datasets that were classified as defective due to head movement were included in this study. All CTP time frames were registered with non-contrast CT data using a 3D rigid registration method. Location and appearance of ischemic area in summary maps derived from original and registered CTP datasets were qualitative compared with follow-up non-contrast CT. A quality score (QS) of 0 to 3 was used to express the degree of agreement. Furthermore, experts compared the quality of both summary maps and assigned the improvement score (IS) of the CTP analysis, ranging from -2 (much worse) to 2 (much better). Summary maps generated from corrected CTP significantly agreed better with appearance of infarct on follow-up CT with mean QS 2.3 versus mean QS 1.8 for summary maps from original CTP (P = 0.024). In comparison to original CTP data, correction resulted in a quality improvement with average IS 0.8: 17 % worsened (IS = -2, -1), 20 % remained unchanged (IS = 0), and 63 % improved (IS = +1, +2). The proposed 3D movement correction improves the summary map quality for CTP datasets with severe head movement. (orig.)

  15. Single beat 3D echocardiography for the assessment of right ventricular dimension and function after endurance exercise: Intraindividual comparison with magnetic resonance imaging

    Schattke Sebastian


    Full Text Available Abstract Background Our study compares new single beat 3D echocardiography (sb3DE to cardiovascular magnetic resonance imaging (CMR for the measurement of right ventricular (RV dimension and function immediately after a 30 km run. This is to validate sb3DE against the "gold standard" CMR and to bring new insights into acute changes of RV dimension and function after endurance exercise. Methods 21 non-elite male marathon runners were examined by sb3DE (Siemens ACUSON SC2000, matrix transducer 4Z1c, volume rates 10-29/s, CMR (Siemens Magnetom Avanto, 1,5 Tesla and blood tests before and immediately after each athlete ran 30 km. The runners were not allowed to rehydrate after the race. The order of sb3DE and CMR examination was randomized. Results Sb3DE for the acquisition of RV dimension and function was feasible in all subjects. The decrease in mean body weight and the significant increase in hematocrit indicated dehydration. RV dimensions measured by CMR were consistently larger than measured by sb3DE. Neither sb3DE nor CMR showed a significant difference in the RV ejection fraction before and after exercise. CMR demonstrated a significant decrease in RV dimensions. Measured by sb3DE, this decrease of RV volumes was not significant. Conclusion First, both methods agree well in the acquisition of systolic RV function. The dimensions of the RV measured by CMR are larger than measured by sb3DE. After exercise, the RV volumes decrease significantly when measured by CMR compared to baseline. Second, endurance exercise seems not to induce acute RV dysfunction in athletes without rehydration.

  16. Comparison of measurements from digital cephalometric radiographs and 3D MDCT-synthetized cephalometric radiographs and the effect of head position

    Kim, Mi Ja; Choi, Bo Ram; Huh, Kyung Hoe; Yi, Won Jin; Heo, Min Suk; Lee, Sam Sun; Choi, Soon Chul [School of Dentistry, Seoul National University, Seoul (Korea, Republic of)


    To investigate the reproducibilities and compare the measurements in digital and MDCT-synthesized cephalometric radiograph, and to investigate the effect of head position on the measurement during imaging with MDCT. Twenty-two dry skulls (combined with mandible) were used in this study. Conventional digital cephalometric radiograph was taken in standard position, and MDCT was taken in standard position and two rotated position (10 .deg. C left rotation and 10 .deg. C right tilting). MDCT data were imported in OnDemand and lateral cephalometric radiograph were synthesized from 3D virtual models. Two types of rotated MDCT data were synthesized with default mode and with corrected mode using both ear rods. For all six images, sixteen angular and eleven linear measurements were made in V-Ceph three times. Reproducibility of measurements was assessed using repeated measures ANOVA and ICC. Linear and angular measurements were compared between digital and five MDCTsynthesized images by Student t-test. All measurements in six types of cephalometric radiograph were not statistically different under ICC examination. Measurements were not different between digital and MDCT-synthesized images (P> .05). Measurements in MDCT-synthesized image in 10 .deg. C left rotation or 10 .deg. C right tilting position showed possibility of difference from digital image in some measurements, and possibility of improvement via realignment of head position using both ear rods. MDCT-synthesized cephalometric radiograph can substitute conventional cephalometric radiograph. The error on head position during imaging with MDCT have possibility that can produce measurement errors with MDCT-synthesized image, and these position error can be corrected by realignment of the head position using both ear rods.

  17. Effects of in-pulse transverse relaxation in 3D ultrashort echo time sequences: analytical derivation, comparison to numerical simulation and experimental application at 3T.

    Springer, Fabian; Steidle, Günter; Martirosian, Petros; Claussen, Claus D; Schick, Fritz


    The introduction of ultrashort-echo-time-(UTE)-sequences to clinical whole-body MR scanners has opened up the field of MR characterization of materials or tissues with extremely fast signal decay. If the transverse relaxation time is in the range of the RF-pulse duration, approximation of the RF-pulse by an instantaneous rotation applied at the middle of the RF-pulse and immediately followed by free relaxation will lead to a distinctly underestimated echo signal. Thus, the regular Ernst equation is not adequate to correctly describe steady state signal under those conditions. The paper presents an analytically derived modified Ernst equation, which correctly describes in-pulse relaxation of transverse magnetization under typical conditions: The equation is valid for rectangular excitation pulses, usually applied in 3D UTE sequences. Longitudinal relaxation time of the specimen must be clearly longer than RF-pulse duration, which is fulfilled for tendons and bony structures as well as many solid materials. Under these conditions, the proposed modified Ernst equation enables adequate and relatively simple calculation of the magnetization of materials or tissues. Analytically derived data are compared to numerical results obtained by using an established Runge-Kutta-algorithm based on the Bloch equations. Validity of the new approach was also tested by systematical measurements of a solid polymeric material on a 3T whole-body MR scanner. Thus, the presented modified Ernst equation provides a suitable basis for T1 measurements, even in tissues with T2 values as short as the RF-pulse duration: independent of RF-pulse duration, the 'variable flip angle method' led to consistent results of longitudinal relaxation time T1, if the T2 relaxation time of the material of interest is known as well.

  18. Evaluation of left atrial function by multidetector computed tomography before left atrial radiofrequency-catheter ablation: Comparison of a manual and automated 3D volume segmentation method

    Wolf, Florian, E-mail: [Department of Radiology, Medical University of Vienna, Vienna (Austria); Ourednicek, Petr [Philips Medical Systems, Prague (Czech Republic); Loewe, Christian [Department of Radiology, Medical University of Vienna, Vienna (Austria); Richter, Bernhard; Goessinger, Heinz David; Gwechenberger, Marianne [Department of Cardiology, Medical University of Vienna, Vienna (Austria); Plank, Christina; Schernthaner, Ruediger Egbert; Toepker, Michael; Lammer, Johannes [Department of Radiology, Medical University of Vienna, Vienna (Austria); Feuchtner, Gudrun M. [Department of Radiology, Innsbruck Medical University, Innsbruck (Austria); Institute of Diagnostic Radiology, University Hospital Zurich (Switzerland)


    Introduction: The purpose of this study was to compare a manual and automated 3D volume segmentation tool for evaluation of left atrial (LA) function by 64-slice multidetector-CT (MDCT). Methods and materials: In 33 patients with paroxysmal atrial fibrillation a MDCT scan was performed before radiofrequency-catheter ablation. Atrial function (minimal volume (LAmin), maximal volume (LAmax), stroke volume (SV), ejection fraction (EF)) was evaluated by two readers using a manual and an automatic tool and measurement time was evaluated. Results: Automated LA volume segmentation failed in one patient due to low LA enhancement (103HU). Mean LAmax, LAmin, SV and EF were 127.7 ml, 93 ml, 34.7 ml, 27.1% by the automated, and 122.7 ml, 89.9 ml, 32.8 ml, 26.3% by the manual method with no significant difference (p > 0.05) and high Pearsons correlation coefficients (r = 0.94, r = 0.94, r = 0.82 and r = 0.85, p < 0.0001), respectively. The automated method was significantly faster (p < 0.001). Interobserver variability was low for both methods with Pearson's correlation coefficients between 0.98 and 0.99 (p < 0.0001). Conclusions: Evaluation of LA volume and function with 64-slice MDCT is feasible with a very low interobserver variability. The automatic method is as accurate as the manual method but significantly less time consuming permitting a routine use in clinical practice before RF-catheter ablation.

  19. Genome comparison of two Exiguobacterium strains from high altitude andean lakes with different arsenic resistance: Identification and 3D modeling of the Acr3 efflux pump.

    Omar Federico Ordoñez


    Full Text Available Arsenic exists in natural systems in a variety of chemical forms, including inorganic arsenite (As [III] and arsenate (As [V]. The majority of living organisms have evolved various mechanisms to avoid occurrence of arsenic inside the cell due to its toxicity. Common core genes include a transcriptional repressor ArsR, an arsenate reductase ArsC, and arsenite efflux pumps ArsB and Acr3. To understand arsenic resistance we have performed arsenic tolerance studies, genomic and bioinformatic analysis of two Exiguobacterium strains, S17 and N139, from the high-altitude Andean Lakes. In these environments high concentrations of arsenic were described in the water due to a natural geochemical phenomenon, therefore, these strains represent an attractive model system for the study of environmental stress and can be readily cultivated. Our experiments show that S17 has a greater tolerance to arsenite (10nM than N139, but similar growth in arsenate (150nM. We sequenced the genome of the two Exiguobacterium and identified an acr3 gene in S17 as the only difference between both species regarding known arsenic resistance genes. To further understand the Acr3 we modeled the 3D structure and identified the location of relevant residues of this protein. Our model is in agreement with previous experiments and allowed us to identify a region where a relevant cysteine lies. This Acr3 membrane efflux pump, present only in S17, may explain its increased tolerance to As(III and is the first Acr3-family protein described in Exiguobacterium genus.

  20. A comparison of 1D analytical model and 3D finite element analysis with experiments for a rosen-type piezoelectric transformer.

    Boukazouha, F; Poulin-Vittrant, G; Tran-Huu-Hue, L P; Bavencoffe, M; Boubenider, F; Rguiti, M; Lethiecq, M


    This article is dedicated to the study of Piezoelectric Transformers (PTs), which offer promising solutions to the increasing need for integrated power electronics modules within autonomous systems. The advantages offered by such transformers include: immunity to electromagnetic disturbances; ease of miniaturisation for example, using conventional micro fabrication processes; and enhanced performance in terms of voltage gain and power efficiency. Central to the adequate description of such transformers is the need for complex analytical modeling tools, especially if one is attempting to include combined contributions due to (i) mechanical phenomena owing to the different propagation modes which differ at the primary and secondary sides of the PT; and (ii) electrical phenomena such as the voltage gain and power efficiency, which depend on the electrical load. The present work demonstrates an original one-dimensional (1D) analytical model, dedicated to a Rosen-type PT and simulation results are successively compared against that of a three-dimensional (3D) Finite Element Analysis (COMSOL Multiphysics software) and experimental results. The Rosen-type PT studied here is based on a single layer soft PZT (P191) with corresponding dimensions 18 mm × 3 mm × 1.5 mm, which operated at the second harmonic of 176 kHz. Detailed simulational and experimental results show that the presented 1D model predicts experimental measurements to within less than 10% error of the voltage gain at the second and third resonance frequency modes. Adjustment of the analytical model parameters is found to decrease errors relative to experimental voltage gain to within 1%, whilst a 2.5% error on the output admittance magnitude at the second resonance mode were obtained. Relying on the unique assumption of one-dimensionality, the present analytical model appears as a useful tool for Rosen-type PT design and behavior understanding.

  1. Advanced Visualization and Analysis of Climate Data using DV3D and UV-CDAT

    Maxwell, T. P.


    .g. simple arithmetic operations (configured using the UV-CDAT "calculator" GUI), regridding, conditioned comparisons, weighted averages, various statistical operations, etc. Several teams are developing parallel versions of these tools that will enable users to analyze and display large data sets that cannot currently be processed with existing desktop tools. This enables scientists to run analyses that were previously intractable due to the large size of the datasets and, using DV3D, seamlessly couple these analyses to advanced visualization methods.Figure. 1. A DV3D workflow with spreadsheet output.


    M. C. Moshobane


    Full Text Available Morphometrics (the measurement of morphological features has been revolutionized by the creation of new techniques to study how organismal shape co-varies with several factors such as ecophenotypy. Ecophenotypy refers to the divergence of phenotypes due to developmental changes induced by local environmental conditions, producing distinct ecophenotypes. None of the techniques hitherto utilized could explicitly address organismal shape in a complete biological form, i.e. three-dimensionally. This study investigates the use of the commercial software, Photomodeler Scanner® (PMSc® three-dimensional (3D modelling software to produce accurate and high-resolution 3D models. Henceforth, the modelling of Subantarctic fur seal (Arctocephalus tropicalis and Antarctic fur seal (Arctocephalus gazella skulls which could allow for 3D measurements. Using this method, sixteen accurate 3D skull models were produced and five metrics were determined. The 3D linear measurements were compared to measurements taken manually with a digital caliper. In addition, repetitive measurements were recorded by varying researchers to determine repeatability. To allow for comparison straight line measurements were taken with the software, assuming that close accord with all manually measured features would illustrate the model’s accurate replication of reality. Measurements were not significantly different demonstrating that realistic 3D skull models can be successfully produced to provide a consistent basis for craniometrics, with the additional benefit of allowing non-linear measurements if required.

  3. Assessing 3d Photogrammetry Techniques in Craniometrics

    Moshobane, M. C.; de Bruyn, P. J. N.; Bester, M. N.


    Morphometrics (the measurement of morphological features) has been revolutionized by the creation of new techniques to study how organismal shape co-varies with several factors such as ecophenotypy. Ecophenotypy refers to the divergence of phenotypes due to developmental changes induced by local environmental conditions, producing distinct ecophenotypes. None of the techniques hitherto utilized could explicitly address organismal shape in a complete biological form, i.e. three-dimensionally. This study investigates the use of the commercial software, Photomodeler Scanner® (PMSc®) three-dimensional (3D) modelling software to produce accurate and high-resolution 3D models. Henceforth, the modelling of Subantarctic fur seal (Arctocephalus tropicalis) and Antarctic fur seal (Arctocephalus gazella) skulls which could allow for 3D measurements. Using this method, sixteen accurate 3D skull models were produced and five metrics were determined. The 3D linear measurements were compared to measurements taken manually with a digital caliper. In addition, repetitive measurements were recorded by varying researchers to determine repeatability. To allow for comparison straight line measurements were taken with the software, assuming that close accord with all manually measured features would illustrate the model's accurate replication of reality. Measurements were not significantly different demonstrating that realistic 3D skull models can be successfully produced to provide a consistent basis for craniometrics, with the additional benefit of allowing non-linear measurements if required.

  4. GPR17: Molecular modeling and dynamics studies of the 3-D structure and purinergic ligand binding features in comparison with P2Y receptors

    Ranghino Graziella


    Full Text Available Abstract Background GPR17 is a G-protein-coupled receptor located at intermediate phylogenetic position between two distinct receptor families: the P2Y and CysLT receptors for extracellular nucleotides and cysteinyl-LTs, respectively. We previously showed that GPR17 can indeed respond to both classes of endogenous ligands and to synthetic compounds active at the above receptor families, thus representing the first fully characterized non-peptide "hybrid" GPCR. In a rat brain focal ischemia model, the selective in vivo knock down of GPR17 by anti-sense technology or P2Y/CysLT antagonists reduced progression of ischemic damage, thus highlighting GPR17 as a novel therapeutic target for stroke. Elucidation of the structure of GPR17 and of ligand binding mechanisms are the necessary steps to obtain selective and potent drugs for this new potential target. On this basis, a 3-D molecular model of GPR17 embedded in a solvated phospholipid bilayer and refined by molecular dynamics simulations has been the first aim of this study. To explore the binding mode of the "purinergic" component of the receptor, the endogenous agonist UDP and two P2Y receptor antagonists demonstrated to be active on GPR17 (MRS2179 and cangrelor were then modeled on the receptor. Results Molecular dynamics simulations suggest that GPR17 nucleotide binding pocket is similar to that described for the other P2Y receptors, although only one of the three basic residues that have been typically involved in ligand recognition is conserved (Arg255. The binding pocket is enclosed between the helical bundle and covered at the top by EL2. Driving interactions are H-bonds and salt bridges between the 6.55 and 6.52 residues and the phosphate moieties of the ligands. An "accessory" binding site in a region formed by the EL2, EL3 and the Nt was also found. Conclusion Nucleotide binding to GPR17 occurs on the same receptor regions identified for already known P2Y receptors. Agonist

  5. Anatomical references for tibial sagittal alignment in total knee arthroplasty: A comparison of three anatomical axes based on 3D reconstructed CT images

    SHAO Jun-jie; Thomas Parker Vail; WANG Qiao-jie; SHEN Hao; CHEN Yun-su; WANG Qi; JIANG Yao


    Background This study was designed to analyze three tibial axis reference lines including the anterior tibial cortex (ATC) line,the fibular line (FL),and the anatomical axis of tibia (AAT) line,to determine which line most closely parallels the mechanical axis (MA) of the tibia in the sagittal plane.The clinical relevance of the study is that through finding a reliable landmark on the leg,a surgeon may minimize posterior tibial slope measurement errors thereby and improving the technique for assuring proper alignment of total knee arthroplasty.Methods The material for this study included CT scans of the tibia from 85 consecutive patients and 168 knees (78 without osteoarthritis (OA) and 90 knees with OA).Measurements of the angles between the tibial mechanical axis and each of three reference lines in the sagittal plane were carried out using 3D imaging software.Results Mean angles of 168 knees were as follows:aMT (3.96±0.85)°,aMF (0.70±0.58)°,and aMA (1.40±0.66)°,(aMT:an angle between MA and ATC,aMF:an angle between MA and FL,aMA:an angle between MA and AAT.All abovementioned angles were measured in the sagittal plane of tibia) and the aMF was significantly smaller than the others (P <0.0001).The mean value of the medial tibial slope angle vs.the MA was (9.19±3.97)°,and this was significantly larger than the mean lateral slope angle of (6.62±4.23)° (P <0.0001).The difference between aMF without OA and with OA was not statistically significant (P=0.5015) and the association between the aMT and aMA was strong (r=0.82,P <0.01).Conclusions FL was more closely parallel to the MA of tibia,and more showed less variation between OA and nonOA controls than ATC and AAT lines.Furthermore,the amount of posterior slope in medial plateau was greater than that in lateral plateau.The findings of this analysis suggest that when using the anterior tibial cortex line as is commonly done with extramedullary tibial resection guides,the tibial resection should be sloped

  6. Comparison of two kinds of 3D-printed osteotomy guide plate in 3D model test-operation for total knee arthroplasty%两种3D打印截骨导板在全膝关节置换模型预手术的应用探讨

    张进; 田晓滨; 王少白; 孙立; 杨先腾; 胡如印; 田家亮; 韩伟; 刘腾


    Objective To compare 2 kinds of 3D-printed osteotomy guide plate in the 3D model test-operation for the total knee arthropiasty (TKA).Methods Enrolled in this study were 15 patients who underwent TKA from 1st to 30th in June 2015.They were 6 males and 9 females,aged from 53 to 86 years (average,67.8 years).Seven left knees and 8 right ones were involved.They took calibrated weight-beating full-length lower-limb X-ray films and thin-slice CT scans of the knee.The lower limb models were constructed using the statistical shape model (SSM) and 2D/3D registration technology.In the simulated digital operation,the angle and position of osteotomy were determined.According to the osteotomy plan,2 kinds of guide plate were designed,groove guide plate (GG group) and screw positioning guide plate (SPG group).The 2 kinds of guide plate and the 3D knee models were 3D-printed using polylactie acid.Then the groove guide plate and the screw positioning guide plate were used and compared in the model test-operations.Results The osteotomy time was 36.5 ± 6.2 minutes in GG group and 27.8± 4,3 minutes in SPG group;the rate of breakage was 26.7% (8/30) in GG group and 0 in SPG group;the thickness deviation of the bone cut was 3.4 ± 2.5 mm in GG group and 1.6 ± 1.7 mm in SPG group.All the comparisons above showed significant between-group differences (P < 0.05).There was no significant difference in the 3D-printing time between the 2 groups (307 ± 28 minutes versus 302 ± 25 minutes) (P > 0.05).Conclusions In the 3D model test-operation for TKA,compared with groove guide plate,application of screw positioning guide plate may lead to less osteotomy time,less thickness deviation of the bone cut from the plan,smoother osteotomy surface and lower breakage rate,but similar 3D-printing time.%目的 比较两种3D打印截骨导板在全膝关节置换(TKA)模型预手术中的应用效果.方法 选取2015年6月行TKA的15例患者行带标定器的下肢全长负重X线正、侧

  7. 3D Participatory Sensing with Low-Cost Mobile Devices for Crop Height Assessment--A Comparison with Terrestrial Laser Scanning Data.

    Marx, Sabrina; Hämmerle, Martin; Klonner, Carolin; Höfle, Bernhard


    The integration of local agricultural knowledge deepens the understanding of complex phenomena such as the association between climate variability, crop yields and undernutrition. Participatory Sensing (PS) is a concept which enables laymen to easily gather geodata with standard low-cost mobile devices, offering new and efficient opportunities for agricultural monitoring. This study presents a methodological approach for crop height assessment based on PS. In-field crop height variations of a maize field in Heidelberg, Germany, are gathered with smartphones and handheld GPS devices by 19 participants. The comparison of crop height values measured by the participants to reference data based on terrestrial laser scanning (TLS) results in R2 = 0.63 for the handheld GPS devices and R2 = 0.24 for the smartphone-based approach. RMSE for the comparison between crop height models (CHM) derived from PS and TLS data is 10.45 cm (GPS devices) and 14.69 cm (smartphones). Furthermore, the results indicate that incorporating participants' cognitive abilities in the data collection process potentially improves the quality data captured with the PS approach. The proposed PS methods serve as a fundament to collect agricultural parameters on field-level by incorporating local people. Combined with other methods such as remote sensing, PS opens new perspectives to support agricultural development.

  8. The comparison between two airborne LiDAR datasets to analyse debris flow initiation in north-western Iceland

    Morino, Costanza; Conway, Susan J.; Balme, Matthew R.; Jordan, Colm; Hillier, John; Sæmundsson, Þorsteinn; Argles, Tom


    A debris flow is a very rapid to extremely rapid flow (e.g., 0.8-28 ms-1) [1], that occurs when coarse and poorly-sorted debris, mixed with water and/or air, move down hill slopes in response to gravity [2]. Both the fluid and the solid have a strong influence on the movement of debris flows. They can be extremely destructive, due to their capability of transporting metre-size boulders [e.g., 3, 4]. There are two main ways in which a debris flow can be initiated: by slope failure or by the "fire hose" effect. The slope failure type is particularly common in alpine regions, where landslides can evolve into debris flows [5], triggered by the coalescence of different slope failures. Steep slope gradients, high pore-water pressures, heavy rainfall and/or snowmelt favour this process. The "fire hose" effect occurs when there is a high concentration of debris accumulated within a pre-existing channel; a surge of water through the channel can then develop into a debris flow by incorporating this debris [e.g. 5-7]. In this study, we examine the triggering style of debris flows above the town of Ísafjörður in the Westfjords of Iceland. The slope above the town is characterised by a large topographic bench upon which 20-35 m of glacial till is perched. The sediments are unstable at the bench margin and thus generate frequent, large, hillslope debris flows [8, 9]. In our new analysis, we report on the comparison between the two airborne LiDAR elevation models (collected in 2007 and 2013 by the UK Natural Environment Research Council Airborne Research and Survey Facility), which display several new debris flows and also related mass movements. From these analyses, we find that debris flows in the region are triggered by simple failure of the glacial till, as recognised before [8, 9]. However, debris flows may also be regenerated by the "fire hose" effect, when debris that has collapsed into chutes is remobilised by a later snowmelt or precipitation event. Comparing

  9. Advanced Data Visualization in Astrophysics: the X3D Pathway

    Vogt, F P A; Verdes-Montenegro, L; Borthakur, S


    Most modern astrophysical datasets are multi-dimensional; a characteristic that can nowadays generally be conserved and exploited scientifically during the data reduction/simulation and analysis cascades. Yet, the same multi-dimensional datasets are systematically cropped, sliced and/or projected to printable two-dimensional (2-D) diagrams at the publication stage. In this article, we introduce the concept of the "X3D pathway" as a mean of simplifying and easing the access to data visualization and publication via three-dimensional (3-D) diagrams. The X3D pathway exploits the facts that 1) the X3D 3-D file format lies at the center of a product tree that includes interactive HTML documents, 3-D printing, and high-end animations, and 2) all high-impact-factor & peer-reviewed journals in Astrophysics are now published (some exclusively) online. We argue that the X3D standard is an ideal vector for sharing multi-dimensional datasets, as it provides direct access to a range of different data visualization tec...

  10. 3D Spectroscopy in Astronomy

    Mediavilla, Evencio; Arribas, Santiago; Roth, Martin; Cepa-Nogué, Jordi; Sánchez, Francisco


    Preface; Acknowledgements; 1. Introductory review and technical approaches Martin M. Roth; 2. Observational procedures and data reduction James E. H. Turner; 3. 3D Spectroscopy instrumentation M. A. Bershady; 4. Analysis of 3D data Pierre Ferruit; 5. Science motivation for IFS and galactic studies F. Eisenhauer; 6. Extragalactic studies and future IFS science Luis Colina; 7. Tutorials: how to handle 3D spectroscopy data Sebastian F. Sánchez, Begona García-Lorenzo and Arlette Pécontal-Rousset.

  11. Spherical 3D isotropic wavelets

    Lanusse, F.; Rassat, A.; Starck, J.-L.


    Context. Future cosmological surveys will provide 3D large scale structure maps with large sky coverage, for which a 3D spherical Fourier-Bessel (SFB) analysis in spherical coordinates is natural. Wavelets are particularly well-suited to the analysis and denoising of cosmological data, but a spherical 3D isotropic wavelet transform does not currently exist to analyse spherical 3D data. Aims: The aim of this paper is to present a new formalism for a spherical 3D isotropic wavelet, i.e. one based on the SFB decomposition of a 3D field and accompany the formalism with a public code to perform wavelet transforms. Methods: We describe a new 3D isotropic spherical wavelet decomposition based on the undecimated wavelet transform (UWT) described in Starck et al. (2006). We also present a new fast discrete spherical Fourier-Bessel transform (DSFBT) based on both a discrete Bessel transform and the HEALPIX angular pixelisation scheme. We test the 3D wavelet transform and as a toy-application, apply a denoising algorithm in wavelet space to the Virgo large box cosmological simulations and find we can successfully remove noise without much loss to the large scale structure. Results: We have described a new spherical 3D isotropic wavelet transform, ideally suited to analyse and denoise future 3D spherical cosmological surveys, which uses a novel DSFBT. We illustrate its potential use for denoising using a toy model. All the algorithms presented in this paper are available for download as a public code called MRS3D at

  12. 3D IBFV : Hardware-Accelerated 3D Flow Visualization

    Telea, Alexandru; Wijk, Jarke J. van


    We present a hardware-accelerated method for visualizing 3D flow fields. The method is based on insertion, advection, and decay of dye. To this aim, we extend the texture-based IBFV technique for 2D flow visualization in two main directions. First, we decompose the 3D flow visualization problem in a

  13. 3D Elevation Program—Virtual USA in 3D

    Lukas, Vicki; Stoker, J.M.


    The U.S. Geological Survey (USGS) 3D Elevation Program (3DEP) uses a laser system called ‘lidar’ (light detection and ranging) to create a virtual reality map of the Nation that is very accurate. 3D maps have many uses with new uses being discovered all the time.  

  14. Interactive 3D multimedia content

    Cellary, Wojciech


    The book describes recent research results in the areas of modelling, creation, management and presentation of interactive 3D multimedia content. The book describes the current state of the art in the field and identifies the most important research and design issues. Consecutive chapters address these issues. These are: database modelling of 3D content, security in 3D environments, describing interactivity of content, searching content, visualization of search results, modelling mixed reality content, and efficient creation of interactive 3D content. Each chapter is illustrated with example a

  15. 3D Bayesian contextual classifiers

    Larsen, Rasmus


    We extend a series of multivariate Bayesian 2-D contextual classifiers to 3-D by specifying a simultaneous Gaussian distribution for the feature vectors as well as a prior distribution of the class variables of a pixel and its 6 nearest 3-D neighbours.......We extend a series of multivariate Bayesian 2-D contextual classifiers to 3-D by specifying a simultaneous Gaussian distribution for the feature vectors as well as a prior distribution of the class variables of a pixel and its 6 nearest 3-D neighbours....

  16. 3-D printers for libraries

    Griffey, Jason


    As the maker movement continues to grow and 3-D printers become more affordable, an expanding group of hobbyists is keen to explore this new technology. In the time-honored tradition of introducing new technologies, many libraries are considering purchasing a 3-D printer. Jason Griffey, an early enthusiast of 3-D printing, has researched the marketplace and seen several systems first hand at the Consumer Electronics Show. In this report he introduces readers to the 3-D printing marketplace, covering such topics asHow fused deposition modeling (FDM) printing workBasic terminology such as build

  17. 3D for Graphic Designers

    Connell, Ellery


    Helping graphic designers expand their 2D skills into the 3D space The trend in graphic design is towards 3D, with the demand for motion graphics, animation, photorealism, and interactivity rapidly increasing. And with the meteoric rise of iPads, smartphones, and other interactive devices, the design landscape is changing faster than ever.2D digital artists who need a quick and efficient way to join this brave new world will want 3D for Graphic Designers. Readers get hands-on basic training in working in the 3D space, including product design, industrial design and visualization, modeling, ani

  18. Toward Improved Solar Irradiance Forecasts: Comparison of Downwelling Surface Shortwave Radiation in Arizona Derived from Satellite with the Gridded Datasets

    Kim, Chang Ki; Holmgren, William F.; Stovern, Michael; Betterton, Eric A.


    The downwelling surface shortwave radiation derived from geostationary satellite imagery was compared with the available datasets for the Southwestern United States. The averaged root mean square errors for our instantaneous estimates ranged from 95.0 to 122.7 W m-2, which is lower than those derived from the MODerate resolution Imaging Spectroradiometer (MODIS). The Modern Era Retrospective-analysis for Research and Applications (MERRA) products were used to compare the hourly mean solar insolation. The three hourly mean downwelling surface shortwave radiation was evaluated by comparing the North American Regional Reanalysis (NARR) and the Clouds and the Earth's Radiant Energy System (CERES) products. Our estimates show the better performance than MERRA, NARR and CERES datasets because of coarse resolution that limits determining the solar dimming due to small clouds.

  19. R3D Align: global pairwise alignment of RNA 3D structures using local superpositions

    Rahrig, Ryan R.; Leontis, Neocles B.; Zirbel, Craig L.


    Motivation: Comparing 3D structures of homologous RNA molecules yields information about sequence and structural variability. To compare large RNA 3D structures, accurate automatic comparison tools are needed. In this article, we introduce a new algorithm and web server to align large homologous RNA structures nucleotide by nucleotide using local superpositions that accommodate the flexibility of RNA molecules. Local alignments are merged to form a global alignment by employing a maximum clique algorithm on a specially defined graph that we call the ‘local alignment’ graph. Results: The algorithm is implemented in a program suite and web server called ‘R3D Align’. The R3D Align alignment of homologous 3D structures of 5S, 16S and 23S rRNA was compared to a high-quality hand alignment. A full comparison of the 16S alignment with the other state-of-the-art methods is also provided. The R3D Align program suite includes new diagnostic tools for the structural evaluation of RNA alignments. The R3D Align alignments were compared to those produced by other programs and were found to be the most accurate, in comparison with a high quality hand-crafted alignment and in conjunction with a series of other diagnostics presented. The number of aligned base pairs as well as measures of geometric similarity are used to evaluate the accuracy of the alignments. Availability: R3D Align is freely available through a web server The MATLAB source code of the program suite is also freely available for download at that location. Supplementary information: Supplementary data are available at Bioinformatics online. Contact: PMID:20929913

  20. Nanomaterial datasets to advance tomography in scanning transmission electron microscopy

    Levin, Barnaby D A; Chen, Chien-Chun; Scott, M C; Xu, Rui; Theis, Wolfgang; Jiang, Yi; Yang, Yongsoo; Ophus, Colin; Zhang, Haitao; Ha, Don-Hyung; Wang, Deli; Yu, Yingchao; Abruna, Hector D; Robinson, Richard D; Ercius, Peter; Kourkoutis, Lena F; Miao, Jianwei; Muller, David A; Hovden, Robert


    Electron tomography in materials science has flourished with the demand to characterize nanoscale materials in three dimensions (3D). Access to experimental data is vital for developing and validating reconstruction methods that improve resolution and reduce radiation dose requirements. This work presents five high-quality scanning transmission electron microscope (STEM) tomography datasets in order to address the critical need for open access data in this field. The datasets represent the current limits of experimental technique, are of high quality, and contain materials with structural complexity. Included are tomographic series of a hyperbranched Co2P nanocrystal, platinum nanoparticles on a carbon nanofibre imaged over the complete 180{\\deg} tilt range, a platinum nanoparticle and a tungsten needle both imaged at atomic resolution by equal slope tomography, and a through-focal tilt series of PtCu nanoparticles. A volumetric reconstruction from every dataset is provided for comparison and development of p...

  1. 3D quantification of dynamic fluid-fluid interfaces in porous media with fast x-ray microtomography: A comparison with quasi-equilibrium methods

    Meisenheimer, D.; Brueck, C. L.; Wildenschild, D.


    X-ray microtomography imaging of fluid-fluid interfaces in three-dimensional porous media allows for the testing of thermodynamically derived predictions that seek a unique relationship between capillary pressure, fluid saturation, and specific interfacial area (Pc-Sw-Anw). Previous experimental studies sought to test this functional dependence under quasi-equilibrium conditions (assumed static on the imaging time-scale); however, applying predictive models developed under static conditions for dynamic scenarios can lead to substantial flaws in predicted outcomes. Theory and models developed using dynamic data can be verified using fast x-ray microtomography which allows for the unprecedented measurement of developing interfacial areas, curvatures, and trapping behaviors of fluid phases in three-dimensional systems. We will present results of drainage and imbibition experiments of air and water within a mixture of glass beads. The experiments were performed under both quasi-equilibrium and dynamic conditions at the Advanced Photon Source (APS) at Argonne National Laboratory. Fast x-ray microtomography was achieved by utilizing the high brilliance of the x-ray beam at the APS under pink-beam conditions where the white beam is modified with a 4 mm Al absorber and a 0.8 mrad Pt-coated mirror to eliminate low and high-energy photons, respectively. We present a comparison of the results from the quasi-equilibrium and dynamic experiments in an effort to determine if the Pc-Sw-Anw relationship is comparable under either experimental condition and to add to the discussion on whether the Pc-Sw-Anw relationship is unique as hypothesized by existing theory.

  2. Hydroxypropyl-β-CD vs. its α-homologue for a 3D modified polyrotaxane network formation and properties: the relationship between modified CD and polymer revealed through comparison.

    Li, Zhao; Zheng, Zhen; Su, Shan; Yu, Lin; Wang, Xinling


    The threading mechanism of the hydroxypropyl-cyclodextrin (Hy-CD)/tetrahedron-like poly(ethylene glycol) (tetra-PEG) based host-guest complex and the relationship between Hy-CD and poly(ethylene oxide) (PEO) in the three-dimensional modified polyrotaxane (PR) formed by the complex were revealed through the comparison between Hy-β-CD/tetra-PEG and Hy-α-CD/tetra-PEG based systems from the macroscopic material view to the microscopic molecular view. The complexation between Hy-CD and tetra-PEG in water experiences a threading-dethreading-rethreading process which is controlled by the intermolecular interaction intensity or molecular hindrance depending on the feed ratio of Hy-CD to tetra-PEG. In the 3D modified PR, the methyl group of the Hy part on one Hy-CD can insert into the cavity of the adjacent Hy-CD and interacts with both the interior surface of the cavity and the PEO segment within the cavity if the cavity of Hy-CD is large enough. The threaded Hy-CD in the PR straightens the chain of PEO and suppresses the segment motion of the PEO. With the decrease of the cavity size of Hy-CD, the degree of suppression on the segment motion of PEO increases. Hy-CD threaded on the PEO chain can also deform when the 3D modified PR is compressed, and the degree of deformation increases with the increase of the cavity size of Hy-CD. These results of the modified CD/PEG based complex system set it apart from the unmodified CD/PEG based one, and reveal the structure-property relationship of this new type of Hy-CD/tetra-PEG based 3D modified PR material.

  3. Finite element micro-modelling of a human ankle bone reveals the importance of the trabecular network to mechanical performance: new methods for the generation and comparison of 3D models.

    Parr, W C H; Chamoli, U; Jones, A; Walsh, W R; Wroe, S


    Most modelling of whole bones does not incorporate trabecular geometry and treats bone as a solid non-porous structure. Some studies have modelled trabecular networks in isolation. One study has modelled the performance of whole human bones incorporating trabeculae, although this required considerable computer resources and purpose-written code. The difference between mechanical behaviour in models that incorporate trabecular geometry and non-porous models has not been explored. The ability to easily model trabecular networks may shed light on the mechanical consequences of bone loss in osteoporosis and remodelling after implant insertion. Here we present a Finite Element Analysis (FEA) of a human ankle bone that includes trabecular network geometry. We compare results from this model with results from non-porous models and introduce protocols achievable on desktop computers using widely available softwares. Our findings show that models including trabecular geometry are considerably stiffer than non-porous whole bone models wherein the non-cortical component has the same mass as the trabecular network, suggesting inclusion of trabecular geometry is desirable. We further present new methods for the construction and analysis of 3D models permitting: (1) construction of multi-property, non-porous models wherein cortical layer thickness can be manipulated; (2) maintenance of the same triangle network for the outer cortical bone surface in both 3D reconstruction and non-porous models allowing exact replication of load and restraint cases; and (3) creation of an internal landmark point grid allowing direct comparison between 3D FE Models (FEMs).

  4. Comparison of quality on digital X-ray devices with 3D-capability for ENT-clinical objectives in imaging of temporal bone and paranasal sinuses; Qualitaetsvergleich digitaler 3D-faehiger Roentgenanlagen bei HNO-Fragestellungen am Schlaefenbein und den Nasennebenhoehlen

    Knoergen, M.; Brandt, S.; Koesling, S. [Halle-Wittenberg Univ., Halle (Germany). Universitaetsklinik und Poliklinik fuer Diagnostische Radiologie


    Purpose: Comparison of dosage and spatial resolution of digital X-Ray devices with 3D-capability in head and neck imaging. Materials and Methods: Three on-site X-Ray devices, a general purpose multi-slice CT (CT), a dedicated cone-beam CT (CBCT) and the CT-mode of a device for digital angiography (DSA) of the same generation were compared using paranasal sinus (PNS) and temporal bone imaging protocols. The radiation exposure was measured with a puncture measuring chamber on a CTDI head phantom as well as with chip-strate-dosimeters on an Alderson head phantom in the regions of the eyes and thyroid gland. By using the Alderson head phantom, the specific dosage of the X-Ray device with regard to different protocols was read out. For the assessment of the high-contrast resolution of the devices, images of a self-made phantom were qualitatively analysed by six observers. Results: The three devices showed marked variations in the dosage and spatial resolution depending on the protocol and/or modus. In both parameters, CBCT was superior to CT and DSA using standard protocols, with the difference being less obvious for the investigation with PNS. Conclusion: For high-contrast investigations CBCT CT is a remarkable option in head and neck radiology. (orig.)

  5. Design and implementation of a rotational radiotherapy technique for breast cancer treatment and their comparison with 3-D-Crt irradiation technique; Diseno e implementacion de una tecnica de radioterapia rotacional para tratamiento de cancer de mama y su comparacion contra la tecnica 3D-CRT de irradiacion

    Gutierrez M, J. G.; Lopez V, A.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico); Velazquez T, J. J.; Adame G, C. S. [Centro Medico Nacional Siglo XXI, Hospital de Oncologia, Departamento de Fisica Medica, Av. Cuauhtemoc No. 330, Col. Doctores, 06720 Mexico D. F. (Mexico); Rubio N, O.; Chagoya G, A.; Hernandez G, J. C., E-mail: [Centro Medico Nacional Siglo XXI, Hospital de Oncologia, Departamento de Radioterapia, Av. Cuauhtemoc No. 330, Col. Doctores, 06720 Mexico D. F. (Mexico)


    Breast cancer is one of oncological diseases worldwide, as well in Mexico, which causes even more deaths than cervical cancer; this condition is the second death cause in women aged 30-54 years and threatens all socio-economic groups. The treatment is highly dependent on the stage which is detected and based on protocols that include a combination of surgery, chemotherapy and radiotherapy. This paper studies the main irradiation technique for patients with mastectomy, breast full cycle (irradiation of the chest well and supraclavicular nodes) in their mode Three Dimensional - Conformal Radiation Therapy (3-D-Crt), and compared with the Volumetric Modulated Arc Therapy (VMAT) technique proposed in this paper. In both techniques the prescription was 50 Gy divided into 25 fractions. The techniques were applied in three female patients (being an initial study) with disease of the left side, the target volume and organs at risk were delineated by the medical treating radiation oncologist, the planning system used was Eclipse version 10; for quantitative comparison of both plans indexes of homogeneity were used, con formality, the target volume coverage and normal tissue, sub factors and overdosing, the conformation number and coverage quality. They were evaluated and compared the media, maximum and minimum dose of the organs at risk, based on the fact that the coverage of the target volume, dose gradient and dose at risk organs are acceptable (prescription dose greater that 90% coverage, gradient less that 20% and organs at risk in accordance with the Quantec limitations for both versions). (Author)

  6. 3D Genome Tuner: Compare Multiple Circular Genomes in a 3D Context

    Qi Wang; Qun Liang; Xiuqing Zhang


    Circular genomes, being the largest proportion of sequenced genomes, play an important role in genome analysis. However, traditional 2D circular map only provides an overview and annotations of genome but does not offer feature-based comparison. For remedying these shortcomings, we developed 3D Genome Tuner, a hybrid of circular map and comparative map tools. Its capability of viewing comparisons between multiple circular maps in a 3D space offers great benefits to the study of comparative genomics. The program is freely available(under an LGPL licence)at

  7. Spherical 3D Isotropic Wavelets

    Lanusse, F; Starck, J -L


    Future cosmological surveys will provide 3D large scale structure maps with large sky coverage, for which a 3D Spherical Fourier-Bessel (SFB) analysis in is natural. Wavelets are particularly well-suited to the analysis and denoising of cosmological data, but a spherical 3D isotropic wavelet transform does not currently exist to analyse spherical 3D data. The aim of this paper is to present a new formalism for a spherical 3D isotropic wavelet, i.e. one based on the Fourier-Bessel decomposition of a 3D field and accompany the formalism with a public code to perform wavelet transforms. We describe a new 3D isotropic spherical wavelet decomposition based on the undecimated wavelet transform (UWT) described in Starck et al. 2006. We also present a new fast Discrete Spherical Fourier-Bessel Transform (DSFBT) based on both a discrete Bessel Transform and the HEALPIX angular pixelisation scheme. We test the 3D wavelet transform and as a toy-application, apply a denoising algorithm in wavelet space to the Virgo large...

  8. Improvement of 3D Scanner


    The disadvantage remaining in 3D scanning system and its reasons are discussed. A new host-and-slave structure with high speed image acquisition and processing system is proposed to quicken the image processing and improve the performance of 3D scanning system.

  9. 3D Printing for Bricks

    ECT Team, Purdue


    Building Bytes, by Brian Peters, is a project that uses desktop 3D printers to print bricks for architecture. Instead of using an expensive custom-made printer, it uses a normal standard 3D printer which is available for everyone and makes it more accessible and also easier for fabrication.

  10. 2D vs 3D gamma analysis: Establishment of comparable clinical action limits

    Kiley B Pulliam


    Full Text Available Purpose: As clinics begin to use 3D metrics for intensity-modulated radiation therapy (IMRT quality assurance; these metrics will often produce results different from those produced by their 2D counterparts. 3D and 2D gamma analyses would be expected to produce different values, because of the different search space available. We compared the results of 2D and 3D gamma analysis (where both datasets were generated the same way for clinical treatment plans.                    Methods: 50 IMRT plans were selected from our database and recalculated using Monte Carlo. Treatment planning system-calculated (“evaluated” and Monte Carlo-recalculated (“reference” dose distributions were compared using 2D and 3D gamma analysis. This analysis was performed using a variety of dose-difference (5%, 3%, 2%, and 1% and distance-to-agreement (5, 3, 2, and 1 mm acceptance criteria, low-dose thresholds (5%, 10%, and 15% of the prescription dose, and data grid sizes (1.0, 1.5, and 3.0 mm. Each comparison was evaluated to determine the average 2D and 3D gamma and percentage of pixels passing gamma.Results: Average gamma and percentage of passing pixels for each acceptance criterion demonstrated better agreement for 3D than for 2D analysis for every plan comparison. Average difference in the percentage of passing pixels between the 2D and 3D analyses with no low-dose threshold ranged from 0.9% to 2.1%. Similarly, using a low-dose threshold resulted in a differences ranging from 0.8% to 1.5%. No appreciable differences in gamma with changes in the data density (constant difference: 0.8% for 2D vs. 3D were observed.Conclusion: We found that 3D gamma analysis resulted in up to 2.9% more pixels passing than 2D analysis.  Factors such as inherent dosimeter differences may be an important additional consideration to the extra dimension of available data that was evaluated in this study.------------------------------------Cite this article as

  11. PLOT3D user's manual

    Walatka, Pamela P.; Buning, Pieter G.; Pierce, Larry; Elson, Patricia A.


    PLOT3D is a computer graphics program designed to visualize the grids and solutions of computational fluid dynamics. Seventy-four functions are available. Versions are available for many systems. PLOT3D can handle multiple grids with a million or more grid points, and can produce varieties of model renderings, such as wireframe or flat shaded. Output from PLOT3D can be used in animation programs. The first part of this manual is a tutorial that takes the reader, keystroke by keystroke, through a PLOT3D session. The second part of the manual contains reference chapters, including the helpfile, data file formats, advice on changing PLOT3D, and sample command files.

  12. 3D printing in dentistry.

    Dawood, A; Marti Marti, B; Sauret-Jackson, V; Darwood, A


    3D printing has been hailed as a disruptive technology which will change manufacturing. Used in aerospace, defence, art and design, 3D printing is becoming a subject of great interest in surgery. The technology has a particular resonance with dentistry, and with advances in 3D imaging and modelling technologies such as cone beam computed tomography and intraoral scanning, and with the relatively long history of the use of CAD CAM technologies in dentistry, it will become of increasing importance. Uses of 3D printing include the production of drill guides for dental implants, the production of physical models for prosthodontics, orthodontics and surgery, the manufacture of dental, craniomaxillofacial and orthopaedic implants, and the fabrication of copings and frameworks for implant and dental restorations. This paper reviews the types of 3D printing technologies available and their various applications in dentistry and in maxillofacial surgery.

  13. Using 3D in Visualization

    Wood, Jo; Kirschenbauer, Sabine; Döllner, Jürgen


    The notion of three-dimensionality is applied to five stages of the visualization pipeline. While 3D visulization is most often associated with the visual mapping and representation of data, this chapter also identifies its role in the management and assembly of data, and in the media used...... to display 3D imagery. The extra cartographic degree of freedom offered by using 3D is explored and offered as a motivation for employing 3D in visualization. The use of VR and the construction of virtual environments exploit navigational and behavioral realism, but become most usefil when combined...... with abstracted representations embedded in a 3D space. The interactions between development of geovisualization, the technology used to implement it and the theory surrounding cartographic representation are explored. The dominance of computing technologies, driven particularly by the gaming industry...

  14. Accurate 3D point cloud comparison and volumetric change analysis of Terrestrial Laser Scan data in a hard rock coastal cliff environment

    Earlie, C. S.; Masselink, G.; Russell, P.; Shail, R.; Kingston, K.


    Our understanding of the evolution of hard rock coastlines is limited due to the episodic nature and ';slow' rate at which changes occur. High-resolution surveying techniques, such as Terrestrial Laser Scanning (TLS), have just begun to be adopted as a method of obtaining detailed point cloud data to monitor topographical changes over short periods of time (weeks to months). However, the difficulties involved in comparing consecutive point cloud data sets in a complex three-dimensional plane, such as occlusion due to surface roughness and positioning of data capture point as a result of a consistently changing environment (a beach profile), mean that comparing data sets can lead to errors in the region of 10 - 20 cm. Meshing techniques are often used for point cloud data analysis for simple surfaces, but in surfaces such as rocky cliff faces, this technique has been found to be ineffective. Recession rates of hard rock coastlines in the UK are typically determined using aerial photography or airborne LiDAR data, yet the detail of the important changes occurring to the cliff face and toe are missed using such techniques. In this study we apply an algorithm (M3C2 - Multiscale Model to Model Cloud Comparison), initially developed for analysing fluvial morphological change, that directly compares point to point cloud data using surface normals that are consistent with surface roughness and measure the change that occurs along the normal direction (Lague et al., 2013). The surfaces changes are analysed using a set of user defined scales based on surface roughness and registration error. Once the correct parameters are defined, the volumetric cliff face changes are calculated by integrating the mean distance between the point clouds. The analysis has been undertaken at two hard rock sites identified for their active erosion located on the UK's south west peninsular at Porthleven in south west Cornwall and Godrevy in north Cornwall. Alongside TLS point cloud data, in

  15. Lossless 3-D reconstruction and registration of semi-quantitative gene expression data in the mouse brain.

    Enlow, Matthew A; Ju, Tao; Kakadiaris, Ioannis A; Carson, James P


    As imaging, computing, and data storage technologies improve, there is an increasing opportunity for multiscale analysis of three-dimensional datasets (3-D). Such analysis enables, for example, microscale elements of multiple macroscale specimens to be compared throughout the entire macroscale specimen. Spatial comparisons require bringing datasets into co-alignment. One approach for co-alignment involves elastic deformations of data in addition to rigid alignments. The elastic deformations distort space, and if not accounted for, can distort the information at the microscale. The algorithms developed in this work address this issue by allowing multiple data points to be encoded into a single image pixel, appropriately tracking each data point to ensure lossless data mapping during elastic spatial deformation. This approach was developed and implemented for both 2-D and 3D registration of images. Lossless reconstruction and registration was applied to semi-quantitative cellular gene expression data in the mouse brain, enabling comparison of multiple spatially registered 3-D datasets without any augmentation of the cellular data. Standard reconstruction and registration without the lossless approach resulted in errors in cellular quantities of ∼ 8%.

  16. A Comparison of Multiple Datasets for Monitoring Thermal Time in Urban Areas over the U.S. Upper Midwest

    Cole Krehbiel


    Full Text Available Traditional studies of urban climate used air temperature observations from local urban/rural weather stations in order to analyze the general pattern of higher temperatures in urban areas compared with corresponding rural regions, also known as the Urban Heat Island (UHI effect. More recently, satellite remote sensing datasets of land surface temperature have been exploited to monitor UHIs. While closely linked, air temperature and land surface temperature (LST observations do not measure the same variables. Here we analyze land surface temperature vs. air temperature-based characterization and seasonality of the UHI and the surface UHI (SUHI from 2003 to 2012 over the Upper Midwest region of the United States using LST from MODIS, and air temperature from the Daymet modeled gridded daily air temperature dataset, and compare both datasets to ground station data from first-order weather stations of the Global Historical Climatology Network (GHCN located in eleven urban areas spanning our study region. We first convert the temperature data to metrics of nocturnal, diurnal, and daily thermal time and their annual accumulations to draw conclusions on nighttime vs. daytime and seasonal dynamics of the UHI. In general, the MODIS LST-derived results are able to capture urban–rural differences in daytime, nighttime, and daily thermal time while the Daymet air temperature-derived results show very little urban–rural differences in thermal time. Compared to the GHCN ground station air temperature-derived observations, MODIS LST-derived results are closer in terms of urban–rural differences in nighttime thermal time, while the results from Daymet are closer to the observations from GHCN during the daytime. We also found differences in the seasonal dynamics of UHIs measured by air temperature observations and SUHIs measured by LST observations.

  17. ADT-3D Tumor Detection Assistant in 3D

    Jaime Lazcano Bello


    Full Text Available The present document describes ADT-3D (Three-Dimensional Tumor Detector Assistant, a prototype application developed to assist doctors diagnose, detect and locate tumors in the brain by using CT scan. The reader may find on this document an introduction to tumor detection; ADT-3D main goals; development details; description of the product; motivation for its development; result’s study; and areas of applicability.

  18. Unassisted 3D camera calibration

    Atanassov, Kalin; Ramachandra, Vikas; Nash, James; Goma, Sergio R.


    With the rapid growth of 3D technology, 3D image capture has become a critical part of the 3D feature set on mobile phones. 3D image quality is affected by the scene geometry as well as on-the-device processing. An automatic 3D system usually assumes known camera poses accomplished by factory calibration using a special chart. In real life settings, pose parameters estimated by factory calibration can be negatively impacted by movements of the lens barrel due to shaking, focusing, or camera drop. If any of these factors displaces the optical axes of either or both cameras, vertical disparity might exceed the maximum tolerable margin and the 3D user may experience eye strain or headaches. To make 3D capture more practical, one needs to consider unassisted (on arbitrary scenes) calibration. In this paper, we propose an algorithm that relies on detection and matching of keypoints between left and right images. Frames containing erroneous matches, along with frames with insufficiently rich keypoint constellations, are detected and discarded. Roll, pitch yaw , and scale differences between left and right frames are then estimated. The algorithm performance is evaluated in terms of the remaining vertical disparity as compared to the maximum tolerable vertical disparity.

  19. Bioprinting of 3D hydrogels.

    Stanton, M M; Samitier, J; Sánchez, S


    Three-dimensional (3D) bioprinting has recently emerged as an extension of 3D material printing, by using biocompatible or cellular components to build structures in an additive, layer-by-layer methodology for encapsulation and culture of cells. These 3D systems allow for cell culture in a suspension for formation of highly organized tissue or controlled spatial orientation of cell environments. The in vitro 3D cellular environments simulate the complexity of an in vivo environment and natural extracellular matrices (ECM). This paper will focus on bioprinting utilizing hydrogels as 3D scaffolds. Hydrogels are advantageous for cell culture as they are highly permeable to cell culture media, nutrients, and waste products generated during metabolic cell processes. They have the ability to be fabricated in customized shapes with various material properties with dimensions at the micron scale. 3D hydrogels are a reliable method for biocompatible 3D printing and have applications in tissue engineering, drug screening, and organ on a chip models.

  20. Data Assimilation and Model Evaluation Experiment Datasets.

    Lai, Chung-Chieng A.; Qian, Wen; Glenn, Scott M.


    The Institute for Naval Oceanography, in cooperation with Naval Research Laboratories and universities, executed the Data Assimilation and Model Evaluation Experiment (DAMÉE) for the Gulf Stream region during fiscal years 1991-1993. Enormous effort has gone into the preparation of several high-quality and consistent datasets for model initialization and verification. This paper describes the preparation process, the temporal and spatial scopes, the contents, the structure, etc., of these datasets.The goal of DAMEE and the need of data for the four phases of experiment are briefly stated. The preparation of DAMEE datasets consisted of a series of processes: 1)collection of observational data; 2) analysis and interpretation; 3) interpolation using the Optimum Thermal Interpolation System package; 4) quality control and re-analysis; and 5) data archiving and software documentation.The data products from these processes included a time series of 3D fields of temperature and salinity, 2D fields of surface dynamic height and mixed-layer depth, analysis of the Gulf Stream and rings system, and bathythermograph profiles. To date, these are the most detailed and high-quality data for mesoscale ocean modeling, data assimilation, and forecasting research. Feedback from ocean modeling groups who tested this data was incorporated into its refinement.Suggestions for DAMEE data usages include 1) ocean modeling and data assimilation studies, 2) diagnosis and theorectical studies, and 3) comparisons with locally detailed observations.

  1. Tuotekehitysprojekti: 3D-tulostin

    Pihlajamäki, Janne


    Opinnäytetyössä tutustuttiin 3D-tulostamisen teknologiaan. Työssä käytiin läpi 3D-tulostimesta tehty tuotekehitysprojekti. Sen lisäksi esiteltiin yleisellä tasolla tuotekehitysprosessi ja syntyneiden tulosten mahdollisia suojausmenetelmiä. Tavoitteena tässä työssä oli kehittää markkinoilta jo löytyvää kotitulostin-tasoista 3D-laiteteknologiaa lähemmäksi ammattilaistason ratkaisua. Tavoitteeseen pyrittiin keskittymällä parantamaan laitteella saavutettavaa tulostustarkkuutta ja -nopeutt...

  2. Handbook of 3D integration

    Garrou , Philip; Ramm , Peter


    Edited by key figures in 3D integration and written by top authors from high-tech companies and renowned research institutions, this book covers the intricate details of 3D process technology.As such, the main focus is on silicon via formation, bonding and debonding, thinning, via reveal and backside processing, both from a technological and a materials science perspective. The last part of the book is concerned with assessing and enhancing the reliability of the 3D integrated devices, which is a prerequisite for the large-scale implementation of this emerging technology. Invaluable reading fo

  3. Color 3D Reverse Engineering


    This paper presents a principle and a method of col or 3D laser scanning measurement. Based on the fundamental monochrome 3D measureme nt study, color information capture, color texture mapping, coordinate computati on and other techniques are performed to achieve color 3D measurement. The syste m is designed and composed of a line laser light emitter, one color CCD camera, a motor-driven rotary filter, a circuit card and a computer. Two steps in captu ring object's images in the measurement process: Firs...

  4. Exploration of 3D Printing

    Lin, Zeyu


    3D printing technology is introduced and defined in this Thesis. Some methods of 3D printing are illustrated and their principles are explained with pictures. Most of the essential parts are presented with pictures and their effects are explained within the whole system. Problems on Up! Plus 3D printer are solved and a DIY product is made with this machine. The processes of making product are recorded and the items which need to be noticed during the process are the highlight in this th...

  5. Vel-IO 3D: A tool for 3D velocity model construction, optimization and time-depth conversion in 3D geological modeling workflow

    Maesano, Francesco E.; D'Ambrogi, Chiara


    We present Vel-IO 3D, a tool for 3D velocity model creation and time-depth conversion, as part of a workflow for 3D model building. The workflow addresses the management of large subsurface dataset, mainly seismic lines and well logs, and the construction of a 3D velocity model able to describe the variation of the velocity parameters related to strong facies and thickness variability and to high structural complexity. Although it is applicable in many geological contexts (e.g. foreland basins, large intermountain basins), it is particularly suitable in wide flat regions, where subsurface structures have no surface expression. The Vel-IO 3D tool is composed by three scripts, written in Python 2.7.11, that automate i) the 3D instantaneous velocity model building, ii) the velocity model optimization, iii) the time-depth conversion. They determine a 3D geological model that is consistent with the primary geological constraints (e.g. depth of the markers on wells). The proposed workflow and the Vel-IO 3D tool have been tested, during the EU funded Project GeoMol, by the construction of the 3D geological model of a flat region, 5700 km2 in area, located in the central part of the Po Plain. The final 3D model showed the efficiency of the workflow and Vel-IO 3D tool in the management of large amount of data both in time and depth domain. A 4 layer-cake velocity model has been applied to a several thousand (5000-13,000 m) thick succession, with 15 horizons from Triassic up to Pleistocene, complicated by a Mesozoic extensional tectonics and by buried thrusts related to Southern Alps and Northern Apennines.

  6. Vertex-based diffusion for 3-D mesh denoising.

    Zhang, Ying; Ben Hamza, A


    We present a vertex-based diffusion for 3-D mesh denoising by solving a nonlinear discrete partial differential equation. The core idea behind our proposed technique is to use geometric insight in helping construct an efficient and fast 3-D mesh smoothing strategy to fully preserve the geometric structure of the data. Illustrating experimental results demonstrate a much improved performance of the proposed approach in comparison with existing methods currently used in 3-D mesh smoothing.

  7. Accepting the T3D

    Rich, D.O.; Pope, S.C.; DeLapp, J.G.


    In April, a 128 PE Cray T3D was installed at Los Alamos National Laboratory`s Advanced Computing Laboratory as part of the DOE`s High-Performance Parallel Processor Program (H4P). In conjunction with CRI, the authors implemented a 30 day acceptance test. The test was constructed in part to help them understand the strengths and weaknesses of the T3D. In this paper, they briefly describe the H4P and its goals. They discuss the design and implementation of the T3D acceptance test and detail issues that arose during the test. They conclude with a set of system requirements that must be addressed as the T3D system evolves.

  8. Advanced 3-D Ultrasound Imaging

    Rasmussen, Morten Fischer

    The main purpose of the PhD project was to develop methods that increase the 3-D ultrasound imaging quality available for the medical personnel in the clinic. Acquiring a 3-D volume gives the medical doctor the freedom to investigate the measured anatomy in any slice desirable after the scan has...... been completed. This allows for precise measurements of organs dimensions and makes the scan more operator independent. Real-time 3-D ultrasound imaging is still not as widespread in use in the clinics as 2-D imaging. A limiting factor has traditionally been the low image quality achievable using...... Field II simulations and measurements with the ultrasound research scanner SARUS and a 3.5MHz 1024 element 2-D transducer array. In all investigations, 3-D synthetic aperture imaging achieved a smaller main-lobe, lower sidelobes, higher contrast, and better signal to noise ratio than parallel...

  9. Conducting polymer 3D microelectrodes

    Sasso, Luigi; Vazquez, Patricia; Vedarethinam, Indumathi


    Conducting polymer 3D microelectrodes have been fabricated for possible future neurological applications. A combination of micro-fabrication techniques and chemical polymerization methods has been used to create pillar electrodes in polyaniline and polypyrrole. The thin polymer films obtained...

  10. Comparison of numerical predictions with CO{sub 2} pipeline release datasets of relevance to carbon capture and storage applications

    Wareing, Christopher J. [School of Chemical and Process Engineering, University of Leeds, Leeds, LS2 9JT (United Kingdom); School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT (United Kingdom); Fairweather, Michael; Woolley, Robert M. [School of Chemical and Process Engineering, University of Leeds, Leeds, LS2 9JT (United Kingdom); Falle, S. A. E. G. [School of Mathematics, University of Leeds, Leeds, LS2 9JT (United Kingdom)


    Predicting the correct multi-phase fluid flow behaviour during the discharge process in the near-field of sonic CO{sub 2} jets is of particular importance in assessing the risks associated with transport aspects of carbon capture and storage schemes, given the very different hazard profiles of CO{sub 2} in the gaseous and solid states. In this paper, we apply our state-of-the-art mathematical model implemented in an efficient computational method to available data. Compared to previous applications, an improved equation of state is used. We also compare to all the available data, rather than just subsets as previously, and demonstrate both the improved performance of the fluid flow model and the variation between the available datasets. The condensed phase fraction at the vent, puncture or rupture release point is revealed to be of key importance in understanding the near-field dispersion of sonic CO{sub 2}.

  11. 3D Face Apperance Model

    Lading, Brian; Larsen, Rasmus; Astrom, K


    We build a 3D face shape model, including inter- and intra-shape variations, derive the analytical Jacobian of its resulting 2D rendered image, and show example of its fitting performance with light, pose, id, expression and texture variations......We build a 3D face shape model, including inter- and intra-shape variations, derive the analytical Jacobian of its resulting 2D rendered image, and show example of its fitting performance with light, pose, id, expression and texture variations...

  12. 3D Face Appearance Model

    Lading, Brian; Larsen, Rasmus; Åström, Kalle


    We build a 3d face shape model, including inter- and intra-shape variations, derive the analytical jacobian of its resulting 2d rendered image, and show example of its fitting performance with light, pose, id, expression and texture variations.}......We build a 3d face shape model, including inter- and intra-shape variations, derive the analytical jacobian of its resulting 2d rendered image, and show example of its fitting performance with light, pose, id, expression and texture variations.}...


    Full Text Available TATCCAYMOTIFOSRAMY3D S000256 01-August-2006 (last modified) kehi TATCCAY motif foun...d in rice (O.s.) RAmy3D alpha-amylase gene promoter; Y=T/C; a GATA motif as its antisense sequence; TATCCAY ...motif and G motif (see S000130) are responsible for sugar repression (Toyofuku et al. 1998); GATA; amylase; sugar; repression; rice (Oryza sativa) TATCCAY ...

  14. Adaptation of a resistive model to pesticide volatilization from plants at the field scale: Comparison with a dataset

    Lichiheb, Nebila; Personne, Erwan; Bedos, Carole; Barriuso, Enrique


    Volatilization from plants is known to greatly contribute to pesticide emission into the atmosphere. Modeling would allow estimating this contribution, but few models are actually available because of our poor understanding of processes occurring at the leaf surface, competing with volatilization, and also because available datasets for validating models are lacking. The SURFATM-Pesticides model was developed to predict pesticide volatilization from plants. It is based on the concept of resistances and takes into account two processes competing with volatilization (leaf penetration and photodegradation). Model is here presented and simulated results are compared with the experimental dataset obtained at the field scale for two fungicides applied on wheat, fenpropidin and chlorothalonil. These fungicides were chosen because they are largely used, as well as because of their differentiated vapor pressures. The model simulates the energy balance and surface temperature which are in good agreement with the experimental data, using the climatic variables as inputs. The model also satisfactorily simulates the volatilization fluxes of chlorothalonil. In fact, by integrating estimated rate coefficients of leaf penetration and photodegradation for chlorothalonil giving in the literature, the volatilization fluxes were estimated to be 24.8 ng m-2 s-1 compared to 23.6 ng m-2 s-1 measured by the aerodynamic profile method during the first hours after application. At six days, the cumulated volatilization fluxes were estimated by the model to be 19 g ha-1 compared to 17.5 g ha-1 measured by the inverse modeling approach. However, due to the lack of data to estimate processes competing with volatilization for fenpropidin, the volatilization of this compound is still not well modeled yet. Thus the model confirms that processes competing with volatilization represent an important factor affecting pesticide volatilization from plants.

  15. 中上段食管癌3D-CRT与IMRT肺损伤剂量学的对比研究%Dosimetric Comparison of Intensity-modulated Radiotherapy Versus 3D Conformal Radiotherapy in Treatment of Cancer of Upper/Mid Esophagus

    张莉; 罗辉


    Objective To compared 3D-conformal radiotherapy (3D-CRT)-induced and intensity-modulated radiotherapy (IMRT)-induced pulmonary injury by using 3D treatment planning system,and to explore the optimum treatment strategy for upper/mid esophageal carcinoma.Methods Eight patients with upper/mid esophageal carcinoma were selected in this study. Four different radiotherapy plans were developed for each patient,including 5-field 3D-CRT(CRT5),7-field 3D-CRT(CRT7), 5-field IMRT (IMRT5) and 7-field IMRT (IMRT7). The planning target volume (PTV) received at least 95% of the prescription dose. The mean lung dose (MLD),V5,V10,V20 and V30 were evaluated using dose volume histogram(DVH). All statistics were analyzed using the SPSS version 11.5 software. Results CRT5 plan reduced lung V10 compared with CRT7 (P=0. 006), but V5, V20, V30 and MLD were not different between the two plans(P>0. 008 3). There were no significant differences in lung parameters between IMRT5 and IMRT7.Compared with IMRT plans, V20, V30 and MLD were increased by 3D-CRT, while V5 was decreased by 3D-CRT(P<0. 0083). Conclusion Compared with 3D-CRT, IMRT can reduce the MLD,V20 and V30 to achieve lung sparing in treatment of upper/mid esophageal carcinoma.There were no significant differences in the protection of lung tissues between 5-field and 7-field techniques for both 3D-CRT and IMRT plans.%目的 应用三维适形放疗(3D-CRT)计划比较中上段食管鳞癌3D-CRT和调强放疗(IMRT)的放射性肺损伤情况从而探讨理想的治疗计划模式.方法 8例患者每例分别设计4个放疗计划(CRT-5 、CRT-7、IMRT-5及 IMRT-7),规定PTV至少达到95%处方剂量前提下用DVH评价每个计划的V5 、V10 、V20 、V30及肺 MLD.采用SPSS 11.5软件包进行数据统计与分析.结果 采用3D-CRT技术时,5野的V10优于7野(P=0.006);5野与7野的肺Mean、肺V5、V20、V30(P>0.0083)之间无统计学意义;采用IMRT技术时,5野与7野之间各参数的对

  16. CAVAREV-an open platform for evaluating 3D and 4D cardiac vasculature reconstruction

    Rohkohl, Christopher; Hornegger, Joachim [Pattern Recognition Lab, Department of Computer Science, Friedrich-Alexander University Erlangen-Nuremberg, Martensstr. 3, 91058 Erlangen (Germany); Lauritsch, Guenter [Siemens AG, Healthcare Sector, Siemensstr. 1, 91301 Forchheim (Germany); Keil, Andreas, E-mail: christopher.rohkohl@informatik.uni-erlangen.d, E-mail:, E-mail: andreas.keil@cs.tum.ed, E-mail: joachim.hornegger@informatik.uni-erlangen.d [Computer Aided Medical Procedures and Augmented Reality, TU Muenchen, Boltzmannstr. 3, 85748 Garching (Germany)


    The 3D reconstruction of cardiac vasculature, e.g. the coronary arteries, using C-arm CT (rotational angiography) is an active and challenging field of research. There are numerous publications on different reconstruction techniques. However, there is still a lack of comparability of achieved results for several reasons: foremost, datasets used in publications are not open to public and thus experiments are not reproducible by other researchers. Further, the results highly depend on the vasculature motion, i.e. cardiac and breathing motion patterns which are also not comparable across publications. We aim to close this gap by providing an open platform, called Cavarev (CArdiac VAsculature Reconstruction EValuation). It features two simulated dynamic projection datasets based on the 4D XCAT phantom with contrasted coronary arteries which was derived from patient data. In the first dataset, the vasculature undergoes a continuous periodic motion. The second dataset contains aperiodic heart motion by including additional breathing motion. The geometry calibration and acquisition protocol were obtained from a real-world C-arm system. For qualitative evaluation of the reconstruction results, the correlation of the morphology is used. Two segmentation-based quality measures are introduced which allow us to assess the 3D and 4D reconstruction quality. They are based on the spatial overlap of the vasculature reconstruction with the ground truth. The measures enable a comprehensive analysis and comparison of reconstruction results independent from the utilized reconstruction algorithm. An online platform ( is provided where the datasets can be downloaded, researchers can manage and publish algorithm results and download a reference C++ and Matlab implementation.

  17. Analysis of a simulated microarray dataset: Comparison of methods for data normalisation and detection of differntial expression

    Watson, M.; Perez-Alegre, M.; Denis Baron, M.; Delmas, C.; Dovc, P.; Duval, M.; Foulley, J.L.; Garrido-Pavon, J.J.; Hulsegge, B.; Jafrezic, F.; Jiménez-Marín, A.; Lavric, M.; Lê Cao, K.A.; Marot, G.; Mouzaki, D.; Pool, M.H.; Robert-Granié, C.; San Cristobal, M.; Tosser-Klop, G.; Waddington, D.; Koning, de D.J.


    Microarrays allow researchers to measure the expression of thousands of genes in a single experiment. Before statistical comparisons can be made, the data must be assessed for quality and normalisation procedures must be applied, of which many have been proposed. Methods of comparing the normalised

  18. MPML3D: Scripting Agents for the 3D Internet.

    Prendinger, Helmut; Ullrich, Sebastian; Nakasone, Arturo; Ishizuka, Mitsuru


    The aim of this paper is two-fold. First, it describes a scripting language for specifying communicative behavior and interaction of computer-controlled agents ("bots") in the popular three-dimensional (3D) multiuser online world of "Second Life" and the emerging "OpenSimulator" project. While tools for designing avatars and in-world objects in Second Life exist, technology for nonprogrammer content creators of scenarios involving scripted agents is currently missing. Therefore, we have implemented new client software that controls bots based on the Multimodal Presentation Markup Language 3D (MPML3D), a highly expressive XML-based scripting language for controlling the verbal and nonverbal behavior of interacting animated agents. Second, the paper compares Second Life and OpenSimulator platforms and discusses the merits and limitations of each from the perspective of agent control. Here, we also conducted a small study that compares the network performance of both platforms.

  19. Contribution of regional 3D meniscus and cartilage morphometry by MRI to joint space width in fixed flexion knee radiography—A between-knee comparison in subjects with unilateral joint space narrowing

    Bloecker, K., E-mail: [Institute of Anatomy and Musculoskeletal Research, Paracelsus Medical University, Strubergasse 21, 5020 Salzburg (Austria); Department of Traumatology and Sports Medicine, Paracelsus Medical University, Müllner Hauptstrasse 48, 5020 Salzburg (Austria); Wirth, W., E-mail: [Institute of Anatomy and Musculoskeletal Research, Paracelsus Medical University, Strubergasse 21, 5020 Salzburg (Austria); Chondrometrics GmbH, Ulrichshöglerstrasse 23, 83404 Ainring (Germany); Hunter, D.J., E-mail: [Royal North Shore Hospital and Kolling Institute, University of Sydney, Pacific Highway, St Leonards, Sydney, NSW 2065 (Australia); Duryea, J., E-mail: [Brigham and Women' s Hospital, Harvard Medical School, 75 Francis Street, Boston, MA (United States); Guermazi, A., E-mail: [Boston University School of Medicine, Department of Radiology, 820 Harrison Avenue, FGH Building 3rd Floor, Boston, MA (United States); Boston Imaging Core Lab (BICL), 601 Albany Street, Boston, MA (United States); Kwoh, C.K., E-mail: [Division of Rheumatology and Clinical Immunology, University of Arizona, Tucson, AZ (United States); Division of Rheumatology and Clinical Immunology, University of Pittsburgh and VA, Pittsburgh Healthcare System, 3500 Terrace Street, Biomedical Science Tower South 702, Pittsburgh, PA 15261 (United States); Resch, H., E-mail: [Department of Traumatology and Sports Medicine, Paracelsus Medical University, Müllner Hauptstrasse 48, 5020 Salzburg (Austria); Eckstein, F. [Institute of Anatomy and Musculoskeletal Research, Paracelsus Medical University, Strubergasse 21, 5020 Salzburg (Austria); Chondrometrics GmbH, Ulrichshöglerstrasse 23, 83404 Ainring (Germany)


    Background: Radiographic joint space width (JSW) is considered the reference standard for demonstrating structural therapeutic benefits in knee osteoarthritis. Our objective was to determine the proportion by which 3D (regional) meniscus and cartilage measures explain between-knee differences of JSW in the fixed flexion radiographs. Methods: Segmentation of the medial meniscus and tibial and femoral cartilage was performed in double echo steady state (DESS) images. Quantitative measures of meniscus size and position, femorotibial cartilage thickness, and radiographic JSW (minimum, and fixed locations) were compared between both knees of 60 participants of the Osteoarthritis Initiative, with strictly unilateral medial joint space narrowing (JSN). Statistical analyses (between-knee, within-person comparison) were performed using regression analysis. Results: A strong relationship with side-differences in minimum and a central fixed location JSW was observed for percent tibial plateau coverage by the meniscus (r = .59 and .47; p < .01) and central femoral cartilage thickness (r = .69 and .75; p < .01); other meniscus and cartilage measures displayed lower coefficients. The correlation of central femoral cartilage thickness with JSW (but not that of meniscus measures) was greater (r = .78 and .85; p < .01) when excluding knees with non-optimal alignment between the tibia and X-ray beam. Conclusion: 3D measures of meniscus and cartilage provide significant, independent information in explaining side-differences in radiographic JSW in fixed flexion radiographs. Tibial coverage by the meniscus and central femoral cartilage explained two thirds of the variability in minimum and fixed location JSW. JSW provides a better representation of (central) femorotibial cartilage thickness, when optimal positioning of the fixed flexion radiographs is achieved.

  20. Comparison of the impact of fire, floods, and large herbivore grazing on the 3-D structure and biomass of Mopane Woodland in Kruger National Park using Terrestrial Laser Scanning

    Delgado, A.; Washington-Allen, R. A.; Bruton, R.; Swemmer, A.


    We conducted a study to look at the impact of large herbivore grazing exclusion, fire, and flooding on the three dimensional (3-D) structure and biomass of Mopane woodlands using Terrestrial Laser Scanning (TLS). The study was conducted at the 42-ha Letaba exclosure that is located on the northern shore of the Letaba River in the northern part of Kruger National Park (KNP), South Africa. The study entailed comparison of 4 X 30-m diameter paired plots, with 4 treatment (no grazing) plots within the exclosure and 4 control plots outside. Additionally, the northern 4 plots are in upland savanna vegetation on a gravelly loam stream terrace that had been burned in 2010. The southern 4 plots are in riparian woodlands on sandy loam soils that had been flooded in 2007. TLS data was collected at 4-cm spacing with 30-m range at 4 scans per plot. Scans were registered and a 3-D virtual environment was created for each plot from which canopy cover, plant density, and vegetation height were manually measured and biomass was derived. We used discriminant analysis to test the hypothesis that 4 structurally distinct groups would be detected, i.e., burned ungrazed savanna, burned grazed savanna, flooded ungrazed riparian, and a flooded grazed riparian group. We found that point density of grass and trees across plots correlated significantly with plot biomass. We predicted that exclosure biomass would be greater than biomass outside the exclosure and that upland biomass height and density in the canopy, shrub, and herbaceous layers within the exclosure compared to outside. However, though biomass was distinct, structural features were not in the upland pairs.

  1. From 3D view to 3D print

    Dima, M.; Farisato, G.; Bergomi, M.; Viotto, V.; Magrin, D.; Greggio, D.; Farinato, J.; Marafatto, L.; Ragazzoni, R.; Piazza, D.


    In the last few years 3D printing is getting more and more popular and used in many fields going from manufacturing to industrial design, architecture, medical support and aerospace. 3D printing is an evolution of bi-dimensional printing, which allows to obtain a solid object from a 3D model, realized with a 3D modelling software. The final product is obtained using an additive process, in which successive layers of material are laid down one over the other. A 3D printer allows to realize, in a simple way, very complex shapes, which would be quite difficult to be produced with dedicated conventional facilities. Thanks to the fact that the 3D printing is obtained superposing one layer to the others, it doesn't need any particular work flow and it is sufficient to simply draw the model and send it to print. Many different kinds of 3D printers exist based on the technology and material used for layer deposition. A common material used by the toner is ABS plastics, which is a light and rigid thermoplastic polymer, whose peculiar mechanical properties make it diffusely used in several fields, like pipes production and cars interiors manufacturing. I used this technology to create a 1:1 scale model of the telescope which is the hardware core of the space small mission CHEOPS (CHaracterising ExOPlanets Satellite) by ESA, which aims to characterize EXOplanets via transits observations. The telescope has a Ritchey-Chrétien configuration with a 30cm aperture and the launch is foreseen in 2017. In this paper, I present the different phases for the realization of such a model, focusing onto pros and cons of this kind of technology. For example, because of the finite printable volume (10×10×12 inches in the x, y and z directions respectively), it has been necessary to split the largest parts of the instrument in smaller components to be then reassembled and post-processed. A further issue is the resolution of the printed material, which is expressed in terms of layers

  2. 3D-mallinnus ja 3D-animaatiot biovoimalaitoksesta

    Hiltula, Tytti


    Opinnäytetyössä tehtiin biovoimalaitoksen piirustuksista 3D-mallinnus ja animaatiot. Työn tarkoituksena oli saada valmiiksi Recwell Oy:lle markkinointiin tarkoitetut kuva- ja videomateriaalit. Työssä perehdyttiin 3D-mallintamisen perustietoihin ja lähtökohtiin sekä animaation laatimiseen. Työ laadittiin kokonaisuudessaan AutoCAD-ohjelmalla, ja työn aikana tutustuttiin huolellisesti myös ohjelman käyttöohjeisiin. Piirustusten mitoituksessa huomattiin jo alkuvaiheessa suuria puutteita, ...

  3. YouDash3D: exploring stereoscopic 3D gaming for 3D movie theaters

    Schild, Jonas; Seele, Sven; Masuch, Maic


    Along with the success of the digitally revived stereoscopic cinema, events beyond 3D movies become attractive for movie theater operators, i.e. interactive 3D games. In this paper, we present a case that explores possible challenges and solutions for interactive 3D games to be played by a movie theater audience. We analyze the setting and showcase current issues related to lighting and interaction. Our second focus is to provide gameplay mechanics that make special use of stereoscopy, especially depth-based game design. Based on these results, we present YouDash3D, a game prototype that explores public stereoscopic gameplay in a reduced kiosk setup. It features live 3D HD video stream of a professional stereo camera rig rendered in a real-time game scene. We use the effect to place the stereoscopic effigies of players into the digital game. The game showcases how stereoscopic vision can provide for a novel depth-based game mechanic. Projected trigger zones and distributed clusters of the audience video allow for easy adaptation to larger audiences and 3D movie theater gaming.

  4. Characteristics of Atmospheric Heat Sources over Asia in Summer:Comparison of Results Calculated Using Multiple Reanalysis Datasets

    ZHANG Bo; CHEN Longxun; HE Jinhai; ZHU Congwen; LI Wei


    Using 1979-2000 daily NCEP/NCAR (National Centers for Environmental Prediction/National Center for Atmospheric Research) reanalysis data (version 1, hereafter referred to as NCEP1; version 2, hereafter referred to as NCEP2), ECMWF (European Center for Medium-range Weather Forecasts) reanalysis data (ERA), and the Global Asian Monsoon Experiment (GAME) reanalysis data in summer 1998, the vertically integrated heat source (Q1) in summer is calculated, and results obtained using different datasets are com-pared. The distributions of (Q1) calculated by using NCEP1 are in good agreement with rainfall observations over the Arabian Sea/Indian Peninsula, the Bay of Bengal (BOB), and East China. The distributions of (Q1)revealed by using NCEP2 are unrealistic in the southern Indian Peninsula, the BOB, and the South China Sea. Using ERA, the heat sources over the tropical Asia are in accordance with the summer precipitation,however, the distributions of (Q1) in East China are unreasonable. In the tropical region, the distributions of the summer heat source given by NCEP1 and ERA seem to be more accurate than those revealed by NCEP2. The NCEP1 and NCEP2 data are better for calculating heat sources over the subtropical and eastern regions of mainland China.

  5. Comparing historical and modern methods of Sea Surface Temperature measurement - Part 1: Review of methods, field comparisons and dataset adjustments

    Matthews, J. B. R.


    Sea Surface Temperature (SST) measurements have been obtained from a variety of different platforms, instruments and depths over the post-industrial period. Today most measurements come from ships, moored and drifting buoys and satellites. Shipboard methods include temperature measurement of seawater sampled by bucket and in engine cooling water intakes. Engine intake temperatures are generally thought to average a few tenths of a °C warmer than simultaneous bucket temperatures. Here I review SST measurement methods, studies comparing shipboard methods by field experiment and adjustments applied to SST datasets to account for variable methods. In opposition to contemporary thinking, I find average bucket-intake temperature differences reported from field studies inconclusive. Non-zero average differences often have associated standard deviations that are several times larger than the averages themselves. Further, average differences have been found to vary widely between ships and between cruises on the same ship. The cause of non-zero average differences is typically unclear given the general absence of additional temperature observations to those from buckets and engine intakes. Shipboard measurements appear of variable quality, highly dependent upon the accuracy and precision of the thermometer used and the care of the observer where manually read. Methods are generally poorly documented, with written instructions not necessarily reflecting actual practices of merchant mariners. Measurements cannot be expected to be of high quality where obtained by untrained sailors using thermometers of low accuracy and precision.

  6. Is agritourism eco-friendly? A comparison between agritourisms and other farms in Italy using farm accountancy data network dataset.

    Mastronardi, Luigi; Giaccio, Vincenzo; Giannelli, Agostino; Scardera, Alfonso


    This paper presents the results of research regarding the environmental performances of Italian farms with agritourism compared with farms without agritourism. In Italy, agritourism is considered an agricultural activity and can only be performed by a farmer. Moreover, Italian national legislation forces the farmer to dedicate himself mainly to traditional farming, rather than to tourism activities. For this reason, environmental performances have been highlighted by analyzing only features and production systems of the farms. By utilizing the most frequent indicators used in studies regarding sustainability, the authors show how Italian agritourisms tend to develop more environmentally friendly agricultural methods, which have a positive impact on biodiversity, landscape and natural resources. The empirical analysis is based on the Italian FADN (Farm Accountancy Data Network) dataset. The European FADN was created to represent farms' technical and economic operation in the European Union and on which it drafts the agricultural and rural policies. The dichotomous structure of the dependent variable (presence or absence of agritourism at the farm) has a propensity for an assessment method based on Binary Response Model Regression.

  7. Comparación de costes de tres tratamientos del cáncer de próstata localizado en España: prostatectomía radical, braquiterapia prostática y radioterapia conformacional externa 3D Cost comparison of three treatments for localized prostate cancer in Spain: radical prostatectomy, prostate brachytherapy and external 3D conformal radiotherapy

    Virginia Becerra Bachino


    Full Text Available Objetivo: Comparar los costes de los tratamientos más establecidos para el cáncer de próstata localizado según grupos de riesgo, edad y comorbilidad, desde la perspectiva del proveedor asistencial. Métodos: Comparación de costes en pacientes reclutados consecutivamente entre 2003 y 2005 en una unidad funcional de tratamiento del cáncer de próstata. La utilización de servicios hasta 6 meses después del inicio del tratamiento se obtuvo de las bases de datos hospitalarias, y los costes directos se estimaron mediante cálculo microcoste. La información sobre las características clínicas de los pacientes y los tratamientos recogió prospectivamente. Los costes se compararon mediante tests no paramétricos de comparación de medianas (Kruskall-Wallis y un modelo semilogarítmico de regresión múltiple. Resultados: La diferencia de costes fue estadísticamente significativa: medianas de 3229.10 €, 5369.00 € y 6265.60 € para los pacientes tratados con radioterapia conformacional externa 3D, braquiterapia, y prostatectomía radical retropública, respectivamente (pObjective: To compare the initial costs of the three most established treatments for clinically localized prostate cancer according to risk, age and comorbidity groups, from the healthcare provider's perspective. Methods: We carried out a cost comparison study in a sample of patients consecutively recruited between 2003 and 2005 from a functional unit for prostate cancer treatment in Catalonia (Spain. The use of services up to 6 months after the treatment start date was obtained from hospital databases and direct costs were estimated by micro-cost calculation. Information on the clinical characteristics of patients and treatments was collected prospectively. Costs were compared by using nonparametric tests comparing medians (Kruskall-Wallis and a semi-logarithmic multiple regression model. Results: Among the 398 patients included, the cost difference among treatments was

  8. 3D future internet media

    Dagiuklas, Tasos


    This book describes recent innovations in 3D media and technologies, with coverage of 3D media capturing, processing, encoding, and adaptation, networking aspects for 3D Media, and quality of user experience (QoE). The main contributions are based on the results of the FP7 European Projects ROMEO, which focus on new methods for the compression and delivery of 3D multi-view video and spatial audio, as well as the optimization of networking and compression jointly across the Future Internet ( The delivery of 3D media to individual users remains a highly challenging problem due to the large amount of data involved, diverse network characteristics and user terminal requirements, as well as the user’s context such as their preferences and location. As the number of visual views increases, current systems will struggle to meet the demanding requirements in terms of delivery of constant video quality to both fixed and mobile users. ROMEO will design and develop hybrid-networking solutions that co...

  9. Materialedreven 3d digital formgivning

    Hansen, Flemming Tvede


    Formålet med forskningsprojektet er for det første at understøtte keramikeren i at arbejde eksperimenterende med digital formgivning, og for det andet at bidrage til en tværfaglig diskurs om brugen af digital formgivning. Forskningsprojektet fokuserer på 3d formgivning og derved på 3d digital...... formgivning og Rapid Prototyping (RP). RP er en fællesbetegnelse for en række af de teknikker, der muliggør at overføre den digitale form til 3d fysisk form. Forskningsprojektet koncentrerer sig om to overordnede forskningsspørgsmål. Det første handler om, hvordan viden og erfaring indenfor det keramiske...... fagområde kan blive udnyttet i forhold til 3d digital formgivning. Det andet handler om, hvad en sådan tilgang kan bidrage med, og hvordan den kan blive udnyttet i et dynamisk samspil med det keramiske materiale i formgivningen af 3d keramiske artefakter. Materialedreven formgivning er karakteriseret af en...

  10. Novel 3D media technologies

    Dagiuklas, Tasos


    This book describes recent innovations in 3D media and technologies, with coverage of 3D media capturing, processing, encoding, and adaptation, networking aspects for 3D Media, and quality of user experience (QoE). The contributions are based on the results of the FP7 European Project ROMEO, which focuses on new methods for the compression and delivery of 3D multi-view video and spatial audio, as well as the optimization of networking and compression jointly across the future Internet. The delivery of 3D media to individual users remains a highly challenging problem due to the large amount of data involved, diverse network characteristics and user terminal requirements, as well as the user’s context such as their preferences and location. As the number of visual views increases, current systems will struggle to meet the demanding requirements in terms of delivery of consistent video quality to fixed and mobile users. ROMEO will present hybrid networking solutions that combine the DVB-T2 and DVB-NGH broadcas...

  11. Speaking Volumes About 3-D


    In 1999, Genex submitted a proposal to Stennis Space Center for a volumetric 3-D display technique that would provide multiple users with a 360-degree perspective to simultaneously view and analyze 3-D data. The futuristic capabilities of the VolumeViewer(R) have offered tremendous benefits to commercial users in the fields of medicine and surgery, air traffic control, pilot training and education, computer-aided design/computer-aided manufacturing, and military/battlefield management. The technology has also helped NASA to better analyze and assess the various data collected by its satellite and spacecraft sensors. Genex capitalized on its success with Stennis by introducing two separate products to the commercial market that incorporate key elements of the 3-D display technology designed under an SBIR contract. The company Rainbow 3D(R) imaging camera is a novel, three-dimensional surface profile measurement system that can obtain a full-frame 3-D image in less than 1 second. The third product is the 360-degree OmniEye(R) video system. Ideal for intrusion detection, surveillance, and situation management, this unique camera system offers a continuous, panoramic view of a scene in real time.

  12. Modification of 3D milling machine to 3D printer

    Halamíček, Lukáš


    Tato práce se zabývá přestavbou gravírovací frézky na 3D tiskárnu. V první části se práce zabývá možnými technologiemi 3D tisku a možností jejich využití u přestavby. Dále jsou popsány a vybrány vhodné součásti pro přestavbu. V další části je realizováno řízení ohřevu podložky, trysky a řízení posuvu drátu pomocí softwaru TwinCat od společnosti Beckhoff na průmyslovém počítači. Výsledkem práce by měla být oživená 3D tiskárna. This thesis deals with rebuilding of engraving machine to 3D pri...

  13. Aspects of defects in 3d-3d correspondence

    Gang, Dongmin; Kim, Nakwoo; Romo, Mauricio; Yamazaki, Masahito


    In this paper we study supersymmetric co-dimension 2 and 4 defects in the compactification of the 6d (2, 0) theory of type A N -1 on a 3-manifold M . The so-called 3d-3d correspondence is a relation between complexified Chern-Simons theory (with gauge group SL(N,C) ) on M and a 3d N=2 theory T N [ M ]. We study this correspondence in the presence of supersymmetric defects, which are knots/links inside the 3-manifold. Our study employs a number of different methods: state-integral models for complex Chern-Simons theory, cluster algebra techniques, domain wall theory T [SU( N )], 5d N=2 SYM, and also supergravity analysis through holography. These methods are complementary and we find agreement between them. In some cases the results lead to highly non-trivial predictions on the partition function. Our discussion includes a general expression for the cluster partition function, which can be used to compute in the presence of maximal and certain class of non-maximal punctures when N > 2. We also highlight the non-Abelian description of the 3d N=2 T N [ M ] theory with defect included, when such a description is available. This paper is a companion to our shorter paper [1], which summarizes our main results.

  14. 3-D Vector Flow Imaging

    Holbek, Simon

    studies and in vivo. Phantom measurements are compared with their corresponding reference value, whereas the in vivo measurement is validated against the current golden standard for non-invasive blood velocity estimates, based on magnetic resonance imaging (MRI). The study concludes, that a high precision......, if this significant reduction in the element count can still provide precise and robust 3-D vector flow estimates in a plane. The study concludes that the RC array is capable of estimating precise 3-D vector flow both in a plane and in a volume, despite the low channel count. However, some inherent new challenges......For the last decade, the field of ultrasonic vector flow imaging has gotten an increasingly attention, as the technique offers a variety of new applications for screening and diagnostics of cardiovascular pathologies. The main purpose of this PhD project was therefore to advance the field of 3-D...

  15. 3D vector flow imaging

    Pihl, Michael Johannes

    The main purpose of this PhD project is to develop an ultrasonic method for 3D vector flow imaging. The motivation is to advance the field of velocity estimation in ultrasound, which plays an important role in the clinic. The velocity of blood has components in all three spatial dimensions, yet...... conventional methods can estimate only the axial component. Several approaches for 3D vector velocity estimation have been suggested, but none of these methods have so far produced convincing in vivo results nor have they been adopted by commercial manufacturers. The basis for this project is the Transverse...... on the TO fields are suggested. They can be used to optimize the TO method. In the third part, a TO method for 3D vector velocity estimation is proposed. It employs a 2D phased array transducer and decouples the velocity estimation into three velocity components, which are estimated simultaneously based on 5...

  16. Markerless 3D Face Tracking

    Walder, Christian; Breidt, Martin; Bulthoff, Heinrich


    We present a novel algorithm for the markerless tracking of deforming surfaces such as faces. We acquire a sequence of 3D scans along with color images at 40Hz. The data is then represented by implicit surface and color functions, using a novel partition-of-unity type method of efficiently...... combining local regressors using nearest neighbor searches. Both these functions act on the 4D space of 3D plus time, and use temporal information to handle the noise in individual scans. After interactive registration of a template mesh to the first frame, it is then automatically deformed to track...... the scanned surface, using the variation of both shape and color as features in a dynamic energy minimization problem. Our prototype system yields high-quality animated 3D models in correspondence, at a rate of approximately twenty seconds per timestep. Tracking results for faces and other objects...

  17. Bringing 3D Printing to Geophysical Science Education

    Boghosian, A.; Turrin, M.; Porter, D. F.


    3D printing technology has been embraced by many technical fields, and is rapidly making its way into peoples' homes and schools. While there is a growing educational and hobbyist community engaged in the STEM focused technical and intellectual challenges associated with 3D printing, there is unrealized potential for the earth science community to use 3D printing to communicate scientific research to the public. Moreover, 3D printing offers scientists the opportunity to connect students and the public with novel visualizations of real data. As opposed to introducing terrestrial measurements through the use of colormaps and gradients, scientists can represent 3D concepts with 3D models, offering a more intuitive education tool. Furthermore, the tactile aspect of models make geophysical concepts accessible to a wide range of learning styles like kinesthetic or tactile, and learners including both visually impaired and color-blind students.We present a workflow whereby scientists, students, and the general public will be able to 3D print their own versions of geophysical datasets, even adding time through layering to include a 4th dimension, for a "4D" print. This will enable scientists with unique and expert insights into the data to easily create the tools they need to communicate their research. It will allow educators to quickly produce teaching aids for their students. Most importantly, it will enable the students themselves to translate the 2D representation of geophysical data into a 3D representation of that same data, reinforcing spatial reasoning.

  18. 3D fascicle orientations in triceps surae.

    Rana, Manku; Hamarneh, Ghassan; Wakeling, James M


    The aim of this study was to determine the three-dimensional (3D) muscle fascicle architecture in human triceps surae muscles at different contraction levels and muscle lengths. Six male subjects were tested for three contraction levels (0, 30, and 60% of maximal voluntary contraction) and four ankle angles (-15, 0, 15, and 30° of plantar flexion), and the muscles were imaged with B-mode ultrasound coupled to 3D position sensors. 3D fascicle orientations were represented in terms of pennation angle relative to the major axis of the muscle and azimuthal angle (a new architectural parameter introduced in this study representing the radial angle around the major axis). 3D orientations of the fascicles, and the sheets along which they lie, were regionalized in all the three muscles (medial and lateral gastrocnemius and the soleus) and changed significantly with contraction level and ankle angle. Changes in the azimuthal angle were of similar magnitude to the changes in pennation angle. The 3D information was used for an error analysis to determine the errors in predictions of pennation that would occur in purely two-dimensional studies. A comparison was made for assessing pennation in the same plane for different contraction levels, or for adjusting the scanning plane orientation for different contractions: there was no significant difference between the two simulated scanning conditions for the gastrocnemii; however, a significant difference of 4.5° was obtained for the soleus. Correct probe orientation is thus more critical during estimations of pennation for the soleus than the gastrocnemii due to its more complex fascicle arrangement.

  19. 3D Printed Bionic Nanodevices.

    Kong, Yong Lin; Gupta, Maneesh K; Johnson, Blake N; McAlpine, Michael C


    The ability to three-dimensionally interweave biological and functional materials could enable the creation of bionic devices possessing unique and compelling geometries, properties, and functionalities. Indeed, interfacing high performance active devices with biology could impact a variety of fields, including regenerative bioelectronic medicines, smart prosthetics, medical robotics, and human-machine interfaces. Biology, from the molecular scale of DNA and proteins, to the macroscopic scale of tissues and organs, is three-dimensional, often soft and stretchable, and temperature sensitive. This renders most biological platforms incompatible with the fabrication and materials processing methods that have been developed and optimized for functional electronics, which are typically planar, rigid and brittle. A number of strategies have been developed to overcome these dichotomies. One particularly novel approach is the use of extrusion-based multi-material 3D printing, which is an additive manufacturing technology that offers a freeform fabrication strategy. This approach addresses the dichotomies presented above by (1) using 3D printing and imaging for customized, hierarchical, and interwoven device architectures; (2) employing nanotechnology as an enabling route for introducing high performance materials, with the potential for exhibiting properties not found in the bulk; and (3) 3D printing a range of soft and nanoscale materials to enable the integration of a diverse palette of high quality functional nanomaterials with biology. Further, 3D printing is a multi-scale platform, allowing for the incorporation of functional nanoscale inks, the printing of microscale features, and ultimately the creation of macroscale devices. This blending of 3D printing, novel nanomaterial properties, and 'living' platforms may enable next-generation bionic systems. In this review, we highlight this synergistic integration of the unique properties of nanomaterials with the

  20. Microfluidic 3D Helix Mixers

    Georgette B. Salieb-Beugelaar


    Full Text Available Polymeric microfluidic systems are well suited for miniaturized devices with complex functionality, and rapid prototyping methods for 3D microfluidic structures are increasingly used. Mixing at the microscale and performing chemical reactions at the microscale are important applications of such systems and we therefore explored feasibility, mixing characteristics and the ability to control a chemical reaction in helical 3D channels produced by the emerging thread template method. Mixing at the microscale is challenging because channel size reduction for improving solute diffusion comes at the price of a reduced Reynolds number that induces a strictly laminar flow regime and abolishes turbulence that would be desired for improved mixing. Microfluidic 3D helix mixers were rapidly prototyped in polydimethylsiloxane (PDMS using low-surface energy polymeric threads, twisted to form 2-channel and 3-channel helices. Structure and flow characteristics were assessed experimentally by microscopy, hydraulic measurements and chromogenic reaction, and were modeled by computational fluid dynamics. We found that helical 3D microfluidic systems produced by thread templating allow rapid prototyping, can be used for mixing and for controlled chemical reaction with two or three reaction partners at the microscale. Compared to the conventional T-shaped microfluidic system used as a control device, enhanced mixing and faster chemical reaction was found to occur due to the combination of diffusive mixing in small channels and flow folding due to the 3D helix shape. Thus, microfluidic 3D helix mixers can be rapidly prototyped using the thread template method and are an attractive and competitive method for fluid mixing and chemical reactions at the microscale.

  1. 3D roadmap in neuroangiography: technique and clinical interest

    Soederman, Michael; Andersson, T. [Karolinska Hospital, Department of Neuroradiology, Stockholm (Sweden); Babic, D.; Homan, R. [Philips Medical Systems, Best (Netherlands)


    We present the first clinical results obtained with a novel technique: the three-dimensional [3D] roadmap. The major difference from the standard 2D digital roadmap technique is that the newly developed 3D roadmap is based on a rotational angiography acquisition technique with the two-dimensional [2D] fluoroscopic image as an overlay. Data required for an accurate superimposition of the previously acquired 3D reconstructed image on the interactively made 2D fluoroscopy image, in real time, are stored in the 3D workstation and constitute the calibration dataset. Both datasets are spatially aligned in real time; thus, the 3D image is accurately superimposed on the 2D fluoroscopic image regardless of any change in C-arm position or magnification. The principal advantage of the described roadmap method is that one contrast injection allows the C-arm to be positioned anywhere in the space and allows alterations in the distance between the x-ray tube and the image intensifier as well as changes in image magnification. In the clinical setting, the 3D roadmap facilitated intravascular neuronavigation with concurrent reduction of procedure time and use of contrast medium. (orig.)




    Full Text Available AIM Role of 3 Dimensional Computed Tomography in facial fractures. METHODS AND MATERIALS 133 patients with history of head trauma were scanned using multi slice CT for a period of 2 yrs. Data acquisition was performed using - 16 Slice GE Bright Speed Elite CT Scanner. The datasets were transferred to workstation and VR post-processing protocols were applied. RESULTS 122 patients were male and 11 were female. The mean age of patients with fractures was 32.3 years old. Fractures included the mandible, the maxilla, the frontal bone, the zygomatic arch and the nasal bone. CONCLUSION Continuing advances in computer software algorithms and improved precision in the acquisition of radiographic data makes 3D reformatted CT imaging a necessary complement to traditional 2D CT imaging in the management of complex facial trauma. CT is the investigation of choice in the evaluation of patients with maxillofacial trauma.

  3. Deep 3-D seismic reflection imaging of Precambrian sills in the crystalline crust of Alberta, Canada

    Welford, Joanna Kim


    Using deep 3-D seismic reflection datasets collected by the Canadian petroleum exploration industry in southwestern and northwestern Alberta, the Head-Smashed-In and Winagami Precambrian sill complexes within the crystalline upper crust, previously identified on Lithoprobe 2-D multichannel reflection lines, are investigated to determine their 3-D geometries and reflective characteristics. During seismic processing of the dataset in southwestern Alberta, a recently developed wavelet-based method, Physical Wavelet Frame Denoising, is applied and shown to successfully suppress ground roll contamination while preserving low frequency signals from deeper structures. A new 3-D empirical trace interpolation scheme, DSInt, is developed to address the problem of spatial aliasing associated with 3-D data acquisition. Results from applying the algorithm to both datasets are comparable to available interpolation codes while allowing for greater flexibility in the handling of irregular acquisition geometries and interpolated trace headers. Evidence of the Head-Smashed-In reflector in southwestern Alberta is obtained using a dataset acquired to 8 s TWTT (approx. 24 km depth). From locally coherent, discontinuous pockets of basement reflectivity, the dataset appears to image the tapering western edge of the deep reflections imaged by Lithoprobe. A statistical approach of tracking reflectivity is developed and applied to obtain the spatial and temporal distribution of reflections. Simple 1-D forward modelling results reveal that the brightest reflections likely arise from a 50 to 150 m thick body of high density/high velocity material although variations in the amplitudes and lateral distribution of the reflections indicate that the thickness of the sills is laterally variable. Thus, the results are consistent with imaging the tapering edge of the sill complex. Clear evidence of the Winagami reflection sequence in northwestern Alberta, emerges from the second dataset acquired to 5

  4. Scale Effects of Geographical Soil Datasets on Soil Carbon Estimation in Louisiana, USA: A Comparison of STATSGO and SSURGO

    B. ZHONG; Y. J. XU


    Estimation of soil organic carbon (SOC) pools and fluxes bears large uncertainties because SOC stocks vary greatly over geographical space and through time.Although development of the U.S.Soil Survey Geographic Database (SSURGO),currently the most detailed level with a map scale ranging from 1:12 000 to 1:63 360,has involved substantial government funds and coordinated network efforts,very few studies have utilized it for soil carbon assessment at the large landscape scale.The objectives of this study were to 1) compare estimates in soil organic matter among SSURGO,the State Soil Geographic Database (STATSGO),and referenced field measurements at the soil map unit; 2) examine the influence of missing data on SOC estimation by SSURGO and STATSGO; 3) quantify spatial differences in SOC estimation between SSURGO and STATSGO,specifically for the state of Louisiana; and 4) assess scale effects on soil organic carbon density (SOCD) estimates from a soil map unit to a watershed and a river basin scale.SOC was estimated using soil attributes of SSURGO and STATSGO including soil organic matter (SOM) content,soil layer depth,and bulk density.Paired t-test,correlation,and regression analyses were performed to investigate various relations of SOC and SOM among the datasets.There were positive relations of SOC estimates between SSURGO and STATSGO at the soil map unit (R2 = 0.56,n = 86,t = 1.65,P = 0.102; depth:30 cm).However,the SOC estimated by STATSGO were 9%,33% and 36% lower for the upper 30-cm,the upper l-m,and the maximal depth (up to 2.75 m) soils,respectively,than those from SSURGO.The difference tended to increase as the spatial scale changes from the soil map unit to the watershed and river basin scales.Compared with the referenced field measurements,the estimates in SOM by SSURGO showed a closer match than those of STATSGO,indicating that the former was more accurate than the latter in SOC estimation,both in spatial and temporal resolutions.Further applications

  5. New insights into two distinct nucleosome distributions: comparison of cross-platform positioning datasets in the yeast genome

    Deng Yangyang


    Full Text Available Abstract Background Recently, a number of high-resolution genome-wide maps of nucleosome locations in S. cerevisiae have been derived experimentally. However, nucleosome positions are determined in vivo by the combined effects of numerous factors. Consequently, nucleosomes are not simple static units, which may explain the discrepancies in reported nucleosome positions as measured by different experiments. In order to more accurately depict the genome-wide nucleosome distribution, we integrated multiple nucleosomal positioning datasets using a multi-angle analysis strategy. Results To evaluate the contribution of chromatin structure to transcription, we used the vast amount of available nucleosome analyzed data. Analysis of this data allowed for the comprehensive identification of the connections between promoter nucleosome positioning patterns and various transcription-dependent properties. Further, we characterised the function of nucleosome destabilisation in the context of transcription regulation. Our results indicate that genes with similar nucleosome occupancy patterns share general transcription attributes. We identified the local regulatory correlation (LRC regions for two distinct types of nucleosomes and we assessed their regulatory properties. We also estimated the nucleosome reproducibility and measurement accuracy for high-confidence transcripts. We found that by maintaining a distance of ~13 bp between the upstream border of the +1 nucleosome and the transcription start sites (TSSs, the stable +1 nucleosome may form a barrier against the accessibility of the TSS and shape an optimum chromatin conformation for gene regulation. An in-depth analysis of nucleosome positioning in normally growing and heat shock cells suggested that the extent and patterns of nucleosome sliding are associated with gene activation. Conclusions Our results, which combine different types of data, suggest that cross-platform information, including

  6. Making Inexpensive 3-D Models

    Manos, Harry


    Visual aids are important to student learning, and they help make the teacher's job easier. Keeping with the "TPT" theme of "The Art, Craft, and Science of Physics Teaching," the purpose of this article is to show how teachers, lacking equipment and funds, can construct a durable 3-D model reference frame and a model gravity…

  7. 3D terahertz beam profiling

    Pedersen, Pernille Klarskov; Strikwerda, Andrew; Wang, Tianwu


    We present a characterization of THz beams generated in both a two-color air plasma and in a LiNbO3 crystal. Using a commercial THz camera, we record intensity images as a function of distance through the beam waist, from which we extract 2D beam profiles and visualize our measurements into 3D beam...

  8. 3D Printing: Exploring Capabilities

    Samuels, Kyle; Flowers, Jim


    As 3D printers become more affordable, schools are using them in increasing numbers. They fit well with the emphasis on product design in technology and engineering education, allowing students to create high-fidelity physical models to see and test different iterations in their product designs. They may also help students to "think in three…

  9. When Art Meets 3D


    The presentation of the vanguard work,My Dream3D,the innovative production by the China Disabled People’s Performing Art Troupe(CDPPAT),directed by Joy Joosang Park,provided the film’s domestic premiere at Beijing’s Olympic Park onApril7.The show provided an intriguing insight not

  10. Dynamic 3D MR-defecography

    Ratz, V.; Wech, T.; Schindele, A.; Dierks, A.; Sauer, A.; Reibetanz, J.; Borzi, A.; Bley, T.; Koestler, H.


    Epidemiological studies have estimated the incidence of chronic constipation to be up to 27% of the general population. The gold standard to evaluate affected patients is the dynamic entero-colpo-cysto-defecography. In the clinical routine 2 D MR-defecography is also performed, but only one to three 2 D slices at a temporal footprint of about one second are acquired. To improve the detection of lateral localized pathologies, we developed and implemented dynamic 3 D MR-defecography. Each 3 D block consisted of seven slices with an in-plane spatial resolution of 1.3 x 1.3 mm{sup 2} to 2.3 x 2.3 mm{sup 2} and an image update rate between 0.8 s and 1.3 s. We used a fast bSSFP sequence with a modified stack-of-stars sampling scheme for data acquisition and a modified FISTA compressed sensing algorithm to reconstruct the undersampled datasets. We performed a study including 6 patients to optimize the acquisition parameters with respect to image quality.

  11. 3D analysis of thermal exchange in finned batteries. A comparison between round and elliptical tubes; Analisi tridimensionale dello scambio termico nelle batterie alettate. Confronto fra tubi tondi e tubi ellittici

    Valdiserri, P. [Bologna Univ., Bologna (Italy). Facolta' di Ingegneria, Dipartimento di Ingegneria Energetica, Nucleare e del Controllo Ambientale


    In this paper a numerical 3D analysis of the thermal exchange in air-cooled finned batteries has been carried out. Speed and temperature values in each hub of the numerical simulation domain have been reckoned both at different air flows and with different shapes of the tubes. The thermal power exchanged between tubes and air is obtained by the simulation of a numerical model of a finned battery with round section tubes and is compared to the values obtained for three batteries with elliptical section tubes. The comparison has been performed for different values of the air input speed. [Italian] In questo lavoro e' stata condotta un'analisi numerica tridimensionale dei fenomeni di scambio termico in batterie alettate raffreddate ad aria. I valori di velocita' e temperatura nei singoli nodi del dominio di simulazione numerica sono stati calcolati sia al variare della portata dell'aria sia della forma dei tubi. La potenza termica scambiata tra tubi ed aria, ottenuta dalle simulazioni in un modello numerico di batteria alettata composta da tubi di sezione circolare, e' stata confrontata con i valori ottenuti per tre batterie formate da tubi di sezione elittica. Il confronto e' stato eseguito per diversi valori della velocita' d'ingresso dell'aria.

  12. Dose comparison between three planing prostate: 3-D conformational radiotherapy, coplanar arc therapy and non-coplanar arc therapy; Comparaison dosimetrique de trois balistiques prostatiques: radiotherapie conformationnelle tridimensionnelle, arctherapie coplanaire et arctherapie non-coplanaire

    Voyant, C.; Baadj, A.; Biffi, K.; Leschi, D.; Lantieri, C. [Centre Hospitalier Dept. Castelluccio, Service de Radiotherapie, Ajaccio (France); Voyant, C. [Universite de Corse, Lab. SPE, CNRS-UMR 6134, Corte (France)


    Purpose: Comparative study between a classical conformational prostate radiotherapy (3 D.R.T.C.) and two arc therapy techniques, a coplanar (A.T.-C) and the other non-coplanar (A.T.-N.C.). Patients and Methods:The comparison has been made retrospectively on 30 patients with localized prostate cancer (T.2-T.3a, P.S.A. < 20 ng/ml, Gleason < 7). The objective criteria for comparison were the N.T.C.P., E.U.D., and dose volume (on D.V.H.), for the volumes of bladder wall, rectal wall, femoral heads, small bowel, prostate (P) and seminal vesicles (V.S.). The treatment was 46 Gy on P.T.V.1 (V.S. + P + margins), and then an overdose of 30 Gy on P.T.V.1 (P + margins). Results: For prostate volumes exceeding 75 cm{sup 3}, arc therapy leads to a decrease in uniformity in the target volume and an increase in the dose received by the femoral heads, this method does not seem appropriate. For prostate volumes less than 75 cm{sup 3}, in addition to the coverage almost tumor, and radiation toxicity equivalent to the bladder and the small intestine, there is a significant increase in the dose to the femoral heads, while the remaining is still within limits, such as clinically tolerable. The contribution of arc therapy is mainly observed at the level of rectal doses. The dose received by 30% of the rectum is reduced by - 12% for A.T.-C and - 11.7% for A.T-N.C., and E.U.D. rectum - 5.2% and - 4.8%. Conclusion: In this virtual study, the arc therapy seems to generate a true dose reduction in the rectum wall. These results encourage us to continue the investigation for a possible integration in a dynamic clinical routine. (authors)

  13. SU-E-T-632: A Dosimetric Comparison of the 3D-CRT Planning of Chest Wall in Post-Mastectomy Breast Cancer Patients, with and Without Breast Board Setup

    Muzaffar, Ambreen; Masood, Asif; Ullah, Haseeb; Mehmood, Kashif; Qasim, Uzma; Afridi, M. Ali; Khan, Salim; Hameed, Abdul [Radiation Oncology Department, Shifa International Hospitals Ltd. Sector H-8/4 Islamabad (Pakistan)


    Purpose: Breast boards are used in breast radiation which increases normal lung and heart doses, when supraclavicular field is included. Therefore, in this study through dose volume histogram (DVHs), lung and heart doses comparison was done between two different setups i.e. with and without breast board, for the treatment of left chest wall and supraclavicular fossa in postmastectomy left breast cancer. Methods: In this study, CT-Simulation scans of ten breast cancer patients were done with and without breast board, at Shifa International Hospitals Islamabad, to investigate the differences between the two different setups of the irradiation of left chest wall in terms of lung and heart doses. For immobilization, support under the neck, shoulders and arms was used. Precise PLAN 2.15 treatment planning system (TPS) was used for 3D-CRT planning. The total prescribed dose for both the plans was 5000 cGy/25 fractions. The chest wall was treated with a pair of tangential photon fields and the upper supraclavicular nodal regions were treated with an anterior photon field. A mono-isocentric technique was used to match the tangential fields with the anterior field at the isocentre. The dose volume histogram was used to compare the doses of heart and ipsilateral lung. Results: Both the plans of each patient were generated and compared. DVH results showed that for the same PTV dose coverage, plans without breast board resulted in a reduction of lung and heart doses compared with the plans with breast board. There was significant reductions in V20, V<25 and mean doses for lung and V<9 and mean doses for heart. Conclusion: In comparison of both the plans, setup without breast board significantly reduced the dose-volume of the ipsilateral lung and heart in left chest wall patients. Waived registration request has been submitted.

  14. Cardiac 3D Printing and its Future Directions.

    Vukicevic, Marija; Mosadegh, Bobak; Min, James K; Little, Stephen H


    Three-dimensional (3D) printing is at the crossroads of printer and materials engineering, noninvasive diagnostic imaging, computer-aided design, and structural heart intervention. Cardiovascular applications of this technology development include the use of patient-specific 3D models for medical teaching, exploration of valve and vessel function, surgical and catheter-based procedural planning, and early work in designing and refining the latest innovations in percutaneous structural devices. In this review, we discuss the methods and materials being used for 3D printing today. We discuss the basic principles of clinical image segmentation, including coregistration of multiple imaging datasets to create an anatomic model of interest. With applications in congenital heart disease, coronary artery disease, and surgical and catheter-based structural disease, 3D printing is a new tool that is challenging how we image, plan, and carry out cardiovascular interventions.

  15. Face recognition using SIFT features under 3D meshes

    ZHANG Cheng; GU Yu-zhang; HU Ke-li; WANG Ying-guan


    Expression, occlusion, and pose variations are three main challenges for 3D face recognition. A novel method is presented to address 3D face recognition using scale-invariant feature transform (SIFT) features on 3D meshes. After preprocessing, shape index extrema on the 3D facial surface are selected as keypoints in the difference scale space and the unstable keypoints are removed after two screening steps. Then, a local coordinate system for each keypoint is established by principal component analysis (PCA). Next, two local geometric features are extracted around each keypoint through the local coordinate system. Additionally, the features are augmented by the symmetrization according to the approximate left-right symmetry in human face. The proposed method is evaluated on the Bosphorus, BU-3DFE, and Gavab databases, respectively. Good results are achieved on these three datasets. As a result, the proposed method proves robust to facial expression variations, partial external occlusions and large pose changes.

  16. Priprava 3D modelov za 3D tisk


    Po mnenju nekaterih strokovnjakov bo aditivna proizvodnja (ali 3D tiskanje) spremenila proizvodnjo industrijo, saj si bo vsak posameznik lahko natisnil svoj objekt po želji. V diplomski nalogi so predstavljene nekatere tehnologije aditivne proizvodnje. V nadaljevanju diplomske naloge je predstavljena izdelava makete hiše v merilu 1:100, vse od modeliranja do tiskanja. Poseben poudarek je posvečen predelavi modela, da je primeren za tiskanje, kjer je razvit pristop za hitrejše i...

  17. Post processing of 3D models for 3D printing


    According to the opinion of some experts the additive manufacturing or 3D printing will change manufacturing industry, because any individual could print their own model according to his or her wishes. In this graduation thesis some of the additive manufacturing technologies are presented. Furthermore in the production of house scale model in 1:100 is presented, starting from modeling to printing. Special attention is given to postprocessing of the building model elements us...

  18. Common atlas format and 3D brain atlas reconstructor: infrastructure for constructing 3D brain atlases.

    Majka, Piotr; Kublik, Ewa; Furga, Grzegorz; Wójcik, Daniel Krzysztof


    One of the challenges of modern neuroscience is integrating voluminous data of diferent modalities derived from a variety of specimens. This task requires a common spatial framework that can be provided by brain atlases. The first atlases were limited to two-dimentional presentation of structural data. Recently, attempts at creating 3D atlases have been made to offer navigation within non-standard anatomical planes and improve capability of localization of different types of data within the brain volume. The 3D atlases available so far have been created using frameworks which make it difficult for other researchers to replicate the results. To facilitate reproducible research and data sharing in the field we propose an SVG-based Common Atlas Format (CAF) to store 2D atlas delineations or other compatible data and 3D Brain Atlas Reconstructor (3dBAR), software dedicated to automated reconstruction of three-dimensional brain structures from 2D atlas data. The basic functionality is provided by (1) a set of parsers which translate various atlases from a number of formats into the CAF, and (2) a module generating 3D models from CAF datasets. The whole reconstruction process is reproducible and can easily be configured, tracked and reviewed, which facilitates fixing errors. Manual corrections can be made when automatic reconstruction is not sufficient. The software was designed to simplify interoperability with other neuroinformatics tools by using open file formats. The content can easily be exchanged at any stage of data processing. The framework allows for the addition of new public or proprietary content.

  19. Forensic 3D documentation of skin injuries

    Villa, Chiara


    to create 3D detailed, to-scale, true-color documentation of skin injuries from 2D pictures. A comparison between the measurements of 165 lesions taken during autopsies and on photogrammetrically processed pictures was performed. Different types of lesions were considered: 38 blunt force injuries, 58 sharp...... methods (p > 0.05). The results of intra- and inter-observer tests indicated perfect agreement between the observers with mean value differences of ≤ 0.02 cm. This study demonstrated the validity of using photogrammetry for documentation of injuries in a forensic pathological context. Importantly...

  20. 3D modeling of metallic grain growth

    George, D.; Carlson, N.; Gammel, J.T.; Kuprat, A.


    This paper will describe simulating metallic grain growth using the Gradient Weighted Moving Finite Elements code, GRAIN3D. The authors also describe the set of mesh topology change operations developed to respond to changes in the physical topology such as the collapse of grains and to maintain uniform calculational mesh quality. Validation of the method is demonstrated by comparison to analytic calculations. The authors present results of multigrain simulations where grain boundaries evolve by mean curvature motion and include results which incorporate grain boundary orientation dependence.

  1. A comparison of tropopause heights over China between radiosonde and three reanalysis datasets for the period 1979-2012

    Liu, Hui; Li, Zhenchao; Wei, Hong; Zheng, Zhiyuan; Wei, Zhigang


    We compared the correspondence of tropopause heights over China calculated from the gridded temperature data provided by the ERA-Interim project, NCEP/NCAR Reanalysis Projects-1 (NCEP-1), and Japanese 25-year Reanalysis (JRA-25) project with the radiosonde observational data for 1979-2012. The results indicate that the annual mean ERA-Interim, NCEP-1, and JRA-25 tropopause heights are higher than observations by 203, 228, and 293 gpm, respectively. Large positive differences for the majority of subtropical China primarily contribute to this high bias. An error analysis indicates that the internal coherence of the ERA-Interim data is better than that of NCEP-1 or JRA-25. Although JRA-25 was a second-generation reanalysis, the biases of the JRA-25 and NCEP-1 data relative to the observations remain substantially larger than those of the ERA-Interim. Furthermore, a spatial and temporal comparison of trends also indicates that the ERA-Interim tropopause height changes correspond most closely to the observed trends in China. Overall, our comprehensive analysis of the three reanalysis products indicates that on both seasonal and annual bases, the ERA-Interim tropopause heights are closer to the observations than those of the NCEP-1 or JRA-25 reanalyses. Furthermore, the biases are mainly a result of the algorithm that determines the tropopause height, which is limited by the coarse vertical resolution of the input data.

  2. Analysis of a simulated microarray dataset: Comparison of methods for data normalisation and detection of differential expression (Open Access publication

    Mouzaki Daphné


    Full Text Available Abstract Microarrays allow researchers to measure the expression of thousands of genes in a single experiment. Before statistical comparisons can be made, the data must be assessed for quality and normalisation procedures must be applied, of which many have been proposed. Methods of comparing the normalised data are also abundant, and no clear consensus has yet been reached. The purpose of this paper was to compare those methods used by the EADGENE network on a very noisy simulated data set. With the a priori knowledge of which genes are differentially expressed, it is possible to compare the success of each approach quantitatively. Use of an intensity-dependent normalisation procedure was common, as was correction for multiple testing. Most variety in performance resulted from differing approaches to data quality and the use of different statistical tests. Very few of the methods used any kind of background correction. A number of approaches achieved a success rate of 95% or above, with relatively small numbers of false positives and negatives. Applying stringent spot selection criteria and elimination of data did not improve the false positive rate and greatly increased the false negative rate. However, most approaches performed well, and it is encouraging that widely available techniques can achieve such good results on a very noisy data set.

  3. Long term contaminant migration and impacts from uranium mill tailings. Comparison of computer models using a hypothetical dataset

    Camus, H. [CEA Centre d' Etudes Nucleaires de Fontenay-aux-Roses (France). Inst. de Protection et de Surete Nucleaire] [and others


    The Uranium Mill Tailings Working Group of BIOMOVS II was initiated in Vienna in 1991 with the primary objective of comparing models which can be used to assess the long term impact of radioactive releases from uranium mill tailings, involving multiple pathways, multiple contaminants and multiple environmental receptors. A secondary objective was to examine how these models can be used to assess the fate of stable toxic elements. This is an interim report of the Working Group describing: development of a basic scenario describing a tailings system; application of models in deterministic calculations of contaminant concentrations in biosphere media, and related radiation doses, contaminant intakes and health risks; comparison of model results and review of the modelling. A hypothetical scenario has been developed for contaminant releases from a uranium mill tailings facility. The assumptions for the tailings facility and its environs have been chosen to facilitate the evaluation of potentially important processes incorporated into models. The site description is therefore idealised and does not represent any particular facility or type of facility. Atmospheric and groundwater release source terms have been chosen to facilitate comparison of models and should not be considered realistic. The time and effort taken over derivation of the scenario description and the associated preliminary modelling has been an important and valuable learning exercise. It also reflects the importance of gaining a clear picture of what is being modelled so that comparisons of model results are meaningful. Work within the exercise has contributed to new model development and to improvements and extensions to existing models. The scenario is a simplified description of a real facility and the releases which might occur. No allowance has been made for engineered features on the tailings disposal system which might reduce releases. The source terms have been chosen so as to test the models

  4. Navigation in Orthognathic Surgery: 3D Accuracy.

    Badiali, Giovanni; Roncari, Andrea; Bianchi, Alberto; Taddei, Fulvia; Marchetti, Claudio; Schileo, Enrico


    This article aims to determine the absolute accuracy of maxillary repositioning during orthognathic surgery according to simulation-guided navigation, that is, the combination of navigation and three-dimensional (3D) virtual surgery. We retrospectively studied 15 patients treated for asymmetric dentofacial deformities at the Oral and Maxillofacial Surgery Unit of the S.Orsola-Malpighi University Hospital in Bologna, Italy, from January 2010 to January 2012. Patients were scanned with a cone-beam computed tomography before and after surgery. The virtual surgical simulation was realized with a dedicated software and loaded on a navigation system to improve intraoperative reproducibility of the preoperative planning. We analyzed the outcome following two protocols: (1) planning versus postoperative 3D surface analysis; (2) planning versus postoperative point-based analysis. For 3D surface comparison, the mean Hausdorff distance was measured, and median among cases was 0.99 mm. Median reproducibility orthognathic surgery, if compared with the surgical computer-designed project realized with a dedicated software, particularly for the vertical dimension, which is the most challenging to manage.

  5. Long term contaminant migration and impacts from uranium mill tailings. Comparison of computer models using a realistic dataset

    Camus, H. [CEA Centre d' Etudes Nucleaires de Fontenay-aux-Roses, 92 (France). Inst. de Protection et de Surete Nucleaire] [and others


    This is the final report of the Working Group describing: the enhancement of the previously devised V1 scenario to produce a V2 scenario which includes more detailed source term and other site specific data; the application of models in deterministic and probabilistic mode to calculate contaminant concentrations in biosphere media, and related radiation doses, contaminant intakes and health risks, including estimates of uncertainties; the comparison and analysis of the resulting calculations. A series of scenarios was developed based on data provided by Working Group members from a range of actual tailings disposal sites, culminating in the V2.2 and V2.3 scenarios. The V2.2 and V2.3 scenarios are identical in all respects, except that the V2.2 considers radioactive (U-238 chain) contaminants, whilst the V2.3 considers stable elements (As, Ni, Pb). Since the scenarios are based on data obtained from a range of actual sites, they should be considered to be generically realistic rather than representative of a particular single site. In both scenarios, the contaminants of interest are assumed to be released in leachate from a tailings pile into an underlying aquifer. They are transported in groundwater through the aquifer to a well. Water is abstracted from the well and used for: watering beef cattle; human consumption; and irrigating leafy vegetables. The beef and leafy vegetables are consumed by humans living in the area. The same contaminants are also released into the atmosphere due to the wind erosion of the pile and then deposited upon the soil, pasture and leafy vegetables. In addition, for the V2.2 scenario, Rn-222 is assumed to be released to atmosphere from the pile. Unlike the V1 scenario, no consideration is given to surface water exposure pathways. Results show that there is exceedingly good agreement between participants' deterministic and probabilistic estimates of total dose or intake. They agree within a factor of two to three for both scenarios

  6. Dynamic contrast-enhanced 3D photoacoustic imaging

    Wong, Philip; Kosik, Ivan; Carson, Jeffrey J. L.


    Photoacoustic imaging (PAI) is a hybrid imaging modality that integrates the strengths from both optical imaging and acoustic imaging while simultaneously overcoming many of their respective weaknesses. In previous work, we reported on a real-time 3D PAI system comprised of a 32-element hemispherical array of transducers. Using the system, we demonstrated the ability to capture photoacoustic data, reconstruct a 3D photoacoustic image, and display select slices of the 3D image every 1.4 s, where each 3D image resulted from a single laser pulse. The present study aimed to exploit the rapid imaging speed of an upgraded 3D PAI system by evaluating its ability to perform dynamic contrast-enhanced imaging. The contrast dynamics can provide rich datasets that contain insight into perfusion, pharmacokinetics and physiology. We captured a series of 3D PA images of a flow phantom before and during injection of piglet and rabbit blood. Principal component analysis was utilized to classify the data according to its spatiotemporal information. The results suggested that this technique can be used to separate a sequence of 3D PA images into a series of images representative of main features according to spatiotemporal flow dynamics.

  7. Forensic 3D Scene Reconstruction



    Traditionally law enforcement agencies have relied on basic measurement and imaging tools, such as tape measures and cameras, in recording a crime scene. A disadvantage of these methods is that they are slow and cumbersome. The development of a portable system that can rapidly record a crime scene with current camera imaging, 3D geometric surface maps, and contribute quantitative measurements such as accurate relative positioning of crime scene objects, would be an asset to law enforcement agents in collecting and recording significant forensic data. The purpose of this project is to develop a feasible prototype of a fast, accurate, 3D measurement and imaging system that would support law enforcement agents to quickly document and accurately record a crime scene.

  8. 3D Printed Robotic Hand

    Pizarro, Yaritzmar Rosario; Schuler, Jason M.; Lippitt, Thomas C.


    Dexterous robotic hands are changing the way robots and humans interact and use common tools. Unfortunately, the complexity of the joints and actuations drive up the manufacturing cost. Some cutting edge and commercially available rapid prototyping machines now have the ability to print multiple materials and even combine these materials in the same job. A 3D model of a robotic hand was designed using Creo Parametric 2.0. Combining "hard" and "soft" materials, the model was printed on the Object Connex350 3D printer with the purpose of resembling as much as possible the human appearance and mobility of a real hand while needing no assembly. After printing the prototype, strings where installed as actuators to test mobility. Based on printing materials, the manufacturing cost of the hand was $167, significantly lower than other robotic hands without the actuators since they have more complex assembly processes.

  9. 3D Printable Graphene Composite.

    Wei, Xiaojun; Li, Dong; Jiang, Wei; Gu, Zheming; Wang, Xiaojuan; Zhang, Zengxing; Sun, Zhengzong


    In human being's history, both the Iron Age and Silicon Age thrived after a matured massive processing technology was developed. Graphene is the most recent superior material which could potentially initialize another new material Age. However, while being exploited to its full extent, conventional processing methods fail to provide a link to today's personalization tide. New technology should be ushered in. Three-dimensional (3D) printing fills the missing linkage between graphene materials and the digital mainstream. Their alliance could generate additional stream to push the graphene revolution into a new phase. Here we demonstrate for the first time, a graphene composite, with a graphene loading up to 5.6 wt%, can be 3D printable into computer-designed models. The composite's linear thermal coefficient is below 75 ppm·°C(-1) from room temperature to its glass transition temperature (Tg), which is crucial to build minute thermal stress during the printing process.

  10. SU-E-J-13: Six Degree of Freedom Image Fusion Accuracy for Cranial Target Localization On the Varian Edge Stereotactic Radiosurgery System: Comparison Between 2D/3D and KV CBCT Image Registration

    Xu, H [Wayne State University, Detroit, MI (United States); Song, K; Chetty, I; Kim, J [Henry Ford Health System, Detroit, MI (United States); Wen, N [Henry Ford Health System, West Bloomfield, MI (United States)


    Purpose: To determine the 6 degree of freedom systematic deviations between 2D/3D and CBCT image registration with various imaging setups and fusion algorithms on the Varian Edge Linac. Methods: An anthropomorphic head phantom with radio opaque targets embedded was scanned with CT slice thicknesses of 0.8, 1, 2, and 3mm. The 6 DOF systematic errors were assessed by comparing 2D/3D (kV/MV with CT) with 3D/3D (CBCT with CT) image registrations with different offset positions, similarity measures, image filters, and CBCT slice thicknesses (1 and 2 mm). The 2D/3D registration accuracy of 51 fractions for 26 cranial SRS patients was also evaluated by analyzing 2D/3D pre-treatment verification taken after 3D/3D image registrations. Results: The systematic deviations of 2D/3D image registration using kV- kV, MV-kV and MV-MV image pairs were within ±0.3mm and ±0.3° for translations and rotations with 95% confidence interval (CI) for a reference CT with 0.8 mm slice thickness. No significant difference (P>0.05) on target localization was observed between 0.8mm, 1mm, and 2mm CT slice thicknesses with CBCT slice thicknesses of 1mm and 2mm. With 3mm CT slice thickness, both 2D/3D and 3D/3D registrations performed less accurately in longitudinal direction than thinner CT slice thickness (0.60±0.12mm and 0.63±0.07mm off, respectively). Using content filter and using similarity measure of pattern intensity instead of mutual information, improved the 2D/3D registration accuracy significantly (P=0.02 and P=0.01, respectively). For the patient study, means and standard deviations of residual errors were 0.09±0.32mm, −0.22±0.51mm and −0.07±0.32mm in VRT, LNG and LAT directions, respectively, and 0.12°±0.46°, −0.12°±0.39° and 0.06°±0.28° in RTN, PITCH, and ROLL directions, respectively. 95% CI of translational and rotational deviations were comparable to those in phantom study. Conclusion: 2D/3D image registration provided on the Varian Edge radiosurgery, 6 DOF

  11. Medical 3D thermography system



    Infrared (IR) thermography determines the surface temperature of an object or human body using thermal IR measurement camera. It is an imaging technology which is contactless and completely non-invasive. These propertiesmake IR thermography a useful method of analysis that is used in various industrial applications to detect, monitor and predict irregularities in many fields from engineering to medical and biological observations. This paper presents a conceptual model of Medical 3D Thermo...

  12. Comparison of two single-breath-held 3-D acquisitions with multi-breath-held 2-D cine steady-state free precession MRI acquisition in children with single ventricles

    Atweh, Lamya A.; Dodd, Nicholas A.; Krishnamurthy, Ramkumar; Chu, Zili D. [Texas Children' s Hospital, EB Singleton Department of Pediatric Radiology, Cardiovascular Imaging, Houston, TX (United States); Pednekar, Amol [Philips Healthcare, Houston, TX (United States); Krishnamurthy, Rajesh [Texas Children' s Hospital, EB Singleton Department of Pediatric Radiology, Cardiovascular Imaging, Houston, TX (United States); Baylor College of Medicine, Department of Radiology, Houston, TX (United States); Baylor College of Medicine, Department of Pediatrics, Houston, TX (United States)


    Breath-held two-dimensional balanced steady-state free precession cine acquisition (2-D breath-held SSFP), accelerated with parallel imaging, is the method of choice for evaluating ventricular function due to its superior blood-to-myocardial contrast, edge definition and high intrinsic signal-to-noise ratio throughout the cardiac cycle. The purpose of this study is to qualitatively and quantitatively compare the two different single-breath-hold 3-D cine SSFP acquisitions using 1) multidirectional sensitivity encoding (SENSE) acceleration factors (3-D multiple SENSE SSFP), and 2) k-t broad-use linear acceleration speed-up technique (3-D k-t SSFP) with the conventional 2-D breath-held SSFP in non-sedated asymptomatic volunteers and children with single ventricle congenital heart disease. Our prospective study was performed on 30 non-sedated subjects (9 healthy volunteers and 21 functional single ventricle patients), ages 12.5 +/- 2.8 years. Two-dimensional breath-held SSFP with SENSE acceleration factor of 2, eight-fold accelerated 3-D k-t SSFP, and 3-D multiple SENSE SSFP with total parallel imaging factor of 4 were performed to evaluate ventricular volumes and mass in the short-axis orientation. Image quality scores (blood myocardial contrast, edge definition and interslice alignment) and volumetric analysis (end systolic volume, end diastolic volume and ejection fraction) were performed on the data sets by experienced users. Paired t-test was performed to compare each of the 3-D k-t SSFP and 3-D multiple SENSE SSFP clinical scores against 2-D breath-held SSFP. Bland-Altman analysis was performed on left ventricle (LV) and single ventricle volumetry. Interobserver and intraobserver variability in volumetric measurements were determined using intraclass coefficients. The clinical scores were highest for the 2-D breath-held SSFP images. Between the two 3-D sequences, 3-D multiple SENSE SSFP performed better than 3-D k-t SSFP. Bland-Altman analysis for volumes

  13. Reconstruction of 3-D digital cores using a hybrid method

    Liu Xuefeng; Sun Jianmeng; Wang Haitao


    A 3-D digital core describes the pore space microstructure of rocks. An X-ray micro CT scan is the most accurate and direct but costly method to obtain a 3-D digital core. In this study, we propose a hybrid method which combines sedimentation simulation and simulated annealing (SA) method to generate 3-D digital cores based on 2-D images of rocks. The method starts with the sedimentation simulation to build a 3-D digital core, which is the initial configuration for the SA method. We update the initial digital core using the SA method to match the auto-correlation function of the 2-D rock image and eventually build the final 3-D digital core. Compared with the typical SA method, the hybrid method has significantly reduced the computation time. Local porosity theory is applied to quantitatively compare the reconstructed 3-D digital cores with the X-ray micro CT 3-D images. The results indicate that the 3-D digital cores reconstructed by the hybrid method have homogeneity and geometric connectivity similar to those of the X-ray micro CT image. The formation factors and permeabilities of the reconstructed 3-D digital cores are estimated using the finite element method (FEM) and lattice Boltzmann method (LBM), respectively. The simulated results are in good agreement with the experimental measurements. Comparison of the simulation results suggests that the digital cores reconstructed by the hybrid method more closely reflect the true transport properties than the typical SA method alone.

  14. 3D/3D registration of coronary CTA and biplane XA reconstructions for improved image guidance

    Dibildox, Gerardo, E-mail:; Baka, Nora; Walsum, Theo van [Biomedical Imaging Group Rotterdam, Departments of Radiology and Medical Informatics, Erasmus Medical Center, 3015 GE Rotterdam (Netherlands); Punt, Mark; Aben, Jean-Paul [Pie Medical Imaging, 6227 AJ Maastricht (Netherlands); Schultz, Carl [Department of Cardiology, Erasmus Medical Center, 3015 GE Rotterdam (Netherlands); Niessen, Wiro [Quantitative Imaging Group, Faculty of Applied Sciences, Delft University of Technology, 2628 CJ Delft, The Netherlands and Biomedical Imaging Group Rotterdam, Departments of Radiology and Medical Informatics, Erasmus Medical Center, 3015 GE Rotterdam (Netherlands)


    Purpose: The authors aim to improve image guidance during percutaneous coronary interventions of chronic total occlusions (CTO) by providing information obtained from computed tomography angiography (CTA) to the cardiac interventionist. To this end, the authors investigate a method to register a 3D CTA model to biplane reconstructions. Methods: The authors developed a method for registering preoperative coronary CTA with intraoperative biplane x-ray angiography (XA) images via 3D models of the coronary arteries. The models are extracted from the CTA and biplane XA images, and are temporally aligned based on CTA reconstruction phase and XA ECG signals. Rigid spatial alignment is achieved with a robust probabilistic point set registration approach using Gaussian mixture models (GMMs). This approach is extended by including orientation in the Gaussian mixtures and by weighting bifurcation points. The method is evaluated on retrospectively acquired coronary CTA datasets of 23 CTO patients for which biplane XA images are available. Results: The Gaussian mixture model approach achieved a median registration accuracy of 1.7 mm. The extended GMM approach including orientation was not significantly different (P > 0.1) but did improve robustness with regards to the initialization of the 3D models. Conclusions: The authors demonstrated that the GMM approach can effectively be applied to register CTA to biplane XA images for the purpose of improving image guidance in percutaneous coronary interventions.


    M. Capone


    benefits and the troubles. From a methodological point of view this is our workflow: - theoretical study about geometrical configuration of rib vault systems; - 3D model based on theoretical hypothesis about geometric definition of the vaults' form; - 3D model based on image matching 3D reconstruction methods; - comparison between 3D theoretical model and 3D model based on image matching;

  16. 3D silicon strip detectors

    Parzefall, Ulrich [Physikalisches Institut, Universitaet Freiburg, Hermann-Herder-Str. 3, D-79104 Freiburg (Germany)], E-mail:; Bates, Richard [University of Glasgow, Department of Physics and Astronomy, Glasgow G12 8QQ (United Kingdom); Boscardin, Maurizio [FBK-irst, Center for Materials and Microsystems, via Sommarive 18, 38050 Povo di Trento (Italy); Dalla Betta, Gian-Franco [INFN and Universita' di Trento, via Sommarive 14, 38050 Povo di Trento (Italy); Eckert, Simon [Physikalisches Institut, Universitaet Freiburg, Hermann-Herder-Str. 3, D-79104 Freiburg (Germany); Eklund, Lars; Fleta, Celeste [University of Glasgow, Department of Physics and Astronomy, Glasgow G12 8QQ (United Kingdom); Jakobs, Karl; Kuehn, Susanne [Physikalisches Institut, Universitaet Freiburg, Hermann-Herder-Str. 3, D-79104 Freiburg (Germany); Lozano, Manuel [Instituto de Microelectronica de Barcelona, IMB-CNM, CSIC, Barcelona (Spain); Pahn, Gregor [Physikalisches Institut, Universitaet Freiburg, Hermann-Herder-Str. 3, D-79104 Freiburg (Germany); Parkes, Chris [University of Glasgow, Department of Physics and Astronomy, Glasgow G12 8QQ (United Kingdom); Pellegrini, Giulio [Instituto de Microelectronica de Barcelona, IMB-CNM, CSIC, Barcelona (Spain); Pennicard, David [University of Glasgow, Department of Physics and Astronomy, Glasgow G12 8QQ (United Kingdom); Piemonte, Claudio; Ronchin, Sabina [FBK-irst, Center for Materials and Microsystems, via Sommarive 18, 38050 Povo di Trento (Italy); Szumlak, Tomasz [University of Glasgow, Department of Physics and Astronomy, Glasgow G12 8QQ (United Kingdom); Zoboli, Andrea [INFN and Universita' di Trento, via Sommarive 14, 38050 Povo di Trento (Italy); Zorzi, Nicola [FBK-irst, Center for Materials and Microsystems, via Sommarive 18, 38050 Povo di Trento (Italy)


    While the Large Hadron Collider (LHC) at CERN has started operation in autumn 2008, plans for a luminosity upgrade to the Super-LHC (sLHC) have already been developed for several years. This projected luminosity increase by an order of magnitude gives rise to a challenging radiation environment for tracking detectors at the LHC experiments. Significant improvements in radiation hardness are required with respect to the LHC. Using a strawman layout for the new tracker of the ATLAS experiment as an example, silicon strip detectors (SSDs) with short strips of 2-3 cm length are foreseen to cover the region from 28 to 60 cm distance to the beam. These SSD will be exposed to radiation levels up to 10{sup 15}N{sub eq}/cm{sup 2}, which makes radiation resistance a major concern for the upgraded ATLAS tracker. Several approaches to increasing the radiation hardness of silicon detectors exist. In this article, it is proposed to combine the radiation hard 3D-design originally conceived for pixel-style applications with the benefits of the established planar technology for strip detectors by using SSDs that have regularly spaced doped columns extending into the silicon bulk under the detector strips. The first 3D SSDs to become available for testing were made in the Single Type Column (STC) design, a technological simplification of the original 3D design. With such 3D SSDs, a small number of prototype sLHC detector modules with LHC-speed front-end electronics as used in the semiconductor tracking systems of present LHC experiments were built. Modules were tested before and after irradiation to fluences of 10{sup 15}N{sub eq}/cm{sup 2}. The tests were performed with three systems: a highly focused IR-laser with 5{mu}m spot size to make position-resolved scans of the charge collection efficiency, an Sr{sup 90}{beta}-source set-up to measure the signal levels for a minimum ionizing particle (MIP), and a beam test with 180 GeV pions at CERN. This article gives a brief overview of

  17. A 3D similarity method for scaffold hopping from known drugs or natural ligands to new chemotypes.

    Jenkins, Jeremy L; Glick, Meir; Davies, John W


    A primary goal of 3D similarity searching is to find compounds with similar bioactivity to a reference ligand but with different chemotypes, i.e., "scaffold hopping". However, an adequate description of chemical structures in 3D conformational space is difficult due to the high-dimensionality of the problem. We present an automated method that simplifies flexible 3D chemical descriptions in which clustering techniques traditionally used in data mining are exploited to create "fuzzy" molecular representations called FEPOPS (feature point pharmacophores). The representations can be used for flexible 3D similarity searching given one or more active compounds without a priori knowledge of bioactive conformations or pharmacophores. We demonstrate that similarity searching with FEPOPS significantly enriches for actives taken from in-house high-throughput screening datasets and from MDDR activity classes COX-2, 5-HT3A, and HIV-RT, while also scaffold or ring-system hopping to new chemical frameworks. Further, inhibitors of target proteins (dopamine 2 and retinoic acid receptor) are recalled by FEPOPS by scaffold hopping from their associated endogenous ligands (dopamine and retinoic acid). Importantly, the method excels in comparison to commonly used 2D similarity methods (DAYLIGHT, MACCS, Pipeline Pilot fingerprints) and a commercial 3D method (Pharmacophore Distance Triplets) at finding novel scaffold classes given a single query molecule.

  18. Articular cartilage injury of the knee:comparison of diagnostic value of 3T MR 3D-FS-SPGR sequence with arthroscopy%3T磁共振3D-FS-SPGR序列对膝关节软骨损伤的诊断价值

    谢海柱; 史英红; 岳凤斌; 张刚; 刘奉立


    目的:以关节镜检查结果为标准,分析评价3.0T磁共振3D-FS-SPGR序列对膝关节软骨损伤的诊断价值.方法:对将要进行关节镜检查的50个膝关节进行磁共振多序列、多方位成像,包括矢状位FSE-T2WI、FSE-T1WI、FS-FSE-T2WI、3D-FS-SPGR序列及冠状位、轴位FS-FSE-T2WI序列.利用矢状位3D-FS-SPGR序列图像重建出冠状位及轴位图像.将磁共振检查结果与随后进行的关节镜检查结果进行对照.在MRI上对股骨内外侧髁、胫骨内外侧平台、股骨滑车及髌骨六个关节面关节软骨(共300处)进行评价.另外选取10名志愿者20个膝关节作为对照组进行MR成像.成像序列同患者组.结果:①在FS-FSE-T2wI序列上正常膝关节软骨为光滑的曲线状高信号带,在股骨内、外髁及胫骨平台表面关节软骨呈由表及里的高、低、高3层结构;FSE-T2WI及FSE-T1WI上关节软骨分层现象不明显呈中低信号;在3D-FS-SPGR序列上关节软骨呈明显带状高信号并呈由表及里的高、低、高3层结构;②软骨I级损伤在FS-FSE-T2WI上表现为低或高信号,在3D-FS-SPGR序列上表现为低信号,软骨分层现象消失;软骨缺损(Ⅱ~Ⅳ级损伤)在FSE-T1WI上呈等信号,在FSE-T2WI及FS-FSE-T2WI上表现为高信号,在3D-FS-SPGR上表现为低信号;③3D-FS-SPGR序列对软骨损伤显示的敏感度为91.4%.特异度为95.9%,Kappa值为0.808(>0.75);FS-FSE-T2WI序列的敏感度为88.9%,特异度为96.8%,Kappa值为0.774(>0.75);FSE-T2WI序列的敏感度为75.3%,特异度为98.2%,Kappa值为0.548;FSE-T1WI序列的敏感度为64.2%,特异度为99.1%,Kappa值为0.444.结论:①FSE-T2WI、FSE-T,WI、FSFSE-T2WI、3D-FS-SPGR序列均可以很好的显示膝关节软骨,以3D-FS-SPGR序列显示的最清晰;②3D-FS-SPGR序列显示膝关节软骨损伤优于FSE-T2WI、FSE-T1WI、FS-FSE-T2WI序列,为诊断膝关节软骨损伤的最佳序列.%Objective: To investigate the diagnostic value of different MRI

  19. Face validation using 3D information from single calibrated camera

    Katsarakis, N.; Pnevmatikakis, A.


    propose a novel face validation method based on 3D position estimates from a single calibrated camera. This is done by assuming a typical face width; hence the widths of the detected image regions lead to target position estimates. Detected image regions with extreme position estimates can...... then be discarded. We apply our method on the rich dataset of the CLEAR2007 evaluation campaign, comprising 49 thousand annotated indoors images, recorded at five different sites, from four different cameras per site, depicting approximately 122 thousand faces. Our method yields very accurate 3D position estimates...

  20. Recognizing objects in 3D point clouds with multi-scale local features.

    Lu, Min; Guo, Yulan; Zhang, Jun; Ma, Yanxin; Lei, Yinjie


    Recognizing 3D objects from point clouds in the presence of significant clutter and occlusion is a highly challenging task. In this paper, we present a coarse-to-fine 3D object recognition algorithm. During the phase of offline training, each model is represented with a set of multi-scale local surface features. During the phase of online recognition, a set of keypoints are first detected from each scene. The local surfaces around these keypoints are further encoded with multi-scale feature descriptors. These scene features are then matched against all model features to generate recognition hypotheses, which include model hypotheses and pose hypotheses. Finally, these hypotheses are verified to produce recognition results. The proposed algorithm was tested on two standard datasets, with rigorous comparisons to the state-of-the-art algorithms. Experimental results show that our algorithm was fully automatic and highly effective. It was also very robust to occlusion and clutter. It achieved the best recognition performance on all of these datasets, showing its superiority compared to existing algorithms.

  1. Towards 3D facial reconstruction from uncalibrated CCTV footage

    Dam, van Chris; Veldhuis, Raymond; Spreeuwers, Luuk


    Facial comparison in 2D is an accepted method in law enforcement and forensic investigation, but pose variations, varying light conditions and low resolution video data can reduce the evidential value of the comparison. Some of these problems might be solved by comparing 3D face models: a face model

  2. Application of CT 3D reconstruction in diagnosing atlantoaxial subluxation

    段少银; 林清池; 庞瑞麟


    Objective:To evaluate and compare the diagnostic value in atlantoaxial subluxation by CT three-dimensional (3D) reconstruction.Methods:3D reconstruction fimdings of 41 patients with atlantoaxiai subluxation were retrospectively analyzed, and comparisons were made among images of transverse section, multiplanar reformorting (MPR), surface shade display (SSD), maximum intensity project (MIP), and volume rendering (VR). Results:Of 41 patients with atlantoaxial subluxation, 31 belonged to rotary dislocation, 5 antedislocation, and 5 hind dislocation. All the cases showed the dislocated joint panel of atlantoaxial articulation.Fifteen cases showed deviation of the odontoid process and 8 cases widened distance between the dens and anterior arch of the atlas. The dislocated joint panel of atlantoaxial articulation was more clearly seen with SSD-3D imaging than any other methods. Conclusions:Atlantoaxial subluxation can well be diagnosed by CT 3D reconstruction, in which SSD-3D imaging is optimal.

  3. Numerical Relativity Towards Simulations of 3D Black Hole Coalescence

    Seidel, E


    I review recent developments in numerical relativity, focussing on progress made in 3D black hole evolution. Progress in development of black hole initial data, apparent horizon boundary conditions, adaptive mesh refinement, and characteristic evolution is highlighted, as well as full 3D simulations of colliding and distorted black holes. For true 3D distorted holes, with Cauchy evolution techniques, it is now possible to extract highly accurate, nonaxisymmetric waveforms from fully nonlinear simulations, which are verified by comparison to pertubration theory, and with characteristic techniques extremely long term evolutions of 3D black holes are now possible. I also discuss a new code designed for 3D numerical relativity, called Cactus, that will be made public.

  4. Wireless 3D Chocolate Printer



    Full Text Available This study is for the BSHRM Students of Batangas State University (BatStateU ARASOF for the researchers believe that the Wireless 3D Chocolate Printer would be helpful in their degree program especially on making creative, artistic, personalized and decorative chocolate designs. The researchers used the Prototyping model as procedural method for the successful development and implementation of the hardware and software. This method has five phases which are the following: quick plan, quick design, prototype construction, delivery and feedback and communication. This study was evaluated by the BSHRM Students and the assessment of the respondents regarding the software and hardware application are all excellent in terms of Accuracy, Effecitveness, Efficiency, Maintainability, Reliability and User-friendliness. Also, the overall level of acceptability of the design project as evaluated by the respondents is excellent. With regard to the observation about the best raw material to use in 3D printing, the chocolate is good to use as the printed material is slightly distorted,durable and very easy to prepare; the icing is also good to use as the printed material is not distorted and is very durable but consumes time to prepare; the flour is not good as the printed material is distorted, not durable but it is easy to prepare. The computation of the economic viability level of 3d printer with reference to ROI is 37.14%. The recommendation of the researchers in the design project are as follows: adding a cooling system so that the raw material will be more durable, development of a more simplified version and improving the extrusion process wherein the user do not need to stop the printing process just to replace the empty syringe with a new one.

  5. Interactive 3D Mars Visualization

    Powell, Mark W.


    The Interactive 3D Mars Visualization system provides high-performance, immersive visualization of satellite and surface vehicle imagery of Mars. The software can be used in mission operations to provide the most accurate position information for the Mars rovers to date. When integrated into the mission data pipeline, this system allows mission planners to view the location of the rover on Mars to 0.01-meter accuracy with respect to satellite imagery, with dynamic updates to incorporate the latest position information. Given this information so early in the planning process, rover drivers are able to plan more accurate drive activities for the rover than ever before, increasing the execution of science activities significantly. Scientifically, this 3D mapping information puts all of the science analyses to date into geologic context on a daily basis instead of weeks or months, as was the norm prior to this contribution. This allows the science planners to judge the efficacy of their previously executed science observations much more efficiently, and achieve greater science return as a result. The Interactive 3D Mars surface view is a Mars terrain browsing software interface that encompasses the entire region of exploration for a Mars surface exploration mission. The view is interactive, allowing the user to pan in any direction by clicking and dragging, or to zoom in or out by scrolling the mouse or touchpad. This set currently includes tools for selecting a point of interest, and a ruler tool for displaying the distance between and positions of two points of interest. The mapping information can be harvested and shared through ubiquitous online mapping tools like Google Mars, NASA WorldWind, and Worldwide Telescope.

  6. How 3-D Movies Work



    难度:★★★★☆词数:450 建议阅读时间:8分钟 Most people see out of two eyes. This is a basic fact of humanity,but it’s what makes possible the illusion of depth(纵深幻觉) that 3-D movies create. Human eyes are spaced about two inches apart, meaning that each eye gives the brain a slightly different perspective(透视感)on the same object. The brain then uses this variance to quickly determine an object’s distance.

  7. Virtual 3-D Facial Reconstruction

    Martin Paul Evison


    Full Text Available Facial reconstructions in archaeology allow empathy with people who lived in the past and enjoy considerable popularity with the public. It is a common misconception that facial reconstruction will produce an exact likeness; a resemblance is the best that can be hoped for. Research at Sheffield University is aimed at the development of a computer system for facial reconstruction that will be accurate, rapid, repeatable, accessible and flexible. This research is described and prototypical 3-D facial reconstructions are presented. Interpolation models simulating obesity, ageing and ethnic affiliation are also described. Some strengths and weaknesses in the models, and their potential for application in archaeology are discussed.

  8. Manifold Constrained Transfer of Facial Geometric Knowledge for 3D Caricature Reconstruction

    Jun-Fa Liu; Wen-Jing He; Tao Chen; Yi-Qiang Chen


    3D caricatures are important attractive elements of the interface in virtual environment such as online game.However,very limited 3D caricatures exist in the real world.Meanwhile,creating 3D caricatures manually is rather costly,and even professional skills are needed.This paper proposes a novel and effective manifold transfer algorithm to reconstruct 3D caricatures according to their original 2D caricatures.We first manually create a small dataset with only 100 3D caricature models and use them to initialize the whole 3D dataset.After that,manifold transfer algorithm is carried out to refine the dataset.The algorithm comprises of two steps.The first is to perform manifold alignment between 2D and 3D caricatures to get a "standard" manifold map; the second is to reconstruct all the 3D caricatures based on the manifold map.The proposed approach utilizes and transfers knowledge of 2D caricatures to the target 3D caricatures well.Comparative experiments show that the approach reconstructs 3D caricatures more effectively and the results conform more to the styles of the original 2D caricatures than the Principal Components Analysis (PCA) based method.

  9. Needle segmentation using 3D Hough transform in 3D TRUS guided prostate transperineal therapy

    Qiu Wu [Department of Biomedical Engineering, School of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Imaging Research Laboratories, Robarts Research Institute, Western University, London, Ontario N6A 5K8 (Canada); Yuchi Ming; Ding Mingyue [Department of Biomedical Engineering, School of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Tessier, David; Fenster, Aaron [Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, London, Ontario N6A 5K8 (Canada)


    Purpose: Prostate adenocarcinoma is the most common noncutaneous malignancy in American men with over 200 000 new cases diagnosed each year. Prostate interventional therapy, such as cryotherapy and brachytherapy, is an effective treatment for prostate cancer. Its success relies on the correct needle implant position. This paper proposes a robust and efficient needle segmentation method, which acts as an aid to localize the needle in three-dimensional (3D) transrectal ultrasound (TRUS) guided prostate therapy. Methods: The procedure of locating the needle in a 3D TRUS image is a three-step process. First, the original 3D ultrasound image containing a needle is cropped; the cropped image is then converted to a binary format based on its histogram. Second, a 3D Hough transform based needle segmentation method is applied to the 3D binary image in order to locate the needle axis. The position of the needle endpoint is finally determined by an optimal threshold based analysis of the intensity probability distribution. The overall efficiency is improved through implementing a coarse-fine searching strategy. The proposed method was validated in tissue-mimicking agar phantoms, chicken breast phantoms, and 3D TRUS patient images from prostate brachytherapy and cryotherapy procedures by comparison to the manual segmentation. The robustness of the proposed approach was tested by means of varying parameters such as needle insertion angle, needle insertion length, binarization threshold level, and cropping size. Results: The validation results indicate that the proposed Hough transform based method is accurate and robust, with an achieved endpoint localization accuracy of 0.5 mm for agar phantom images, 0.7 mm for chicken breast phantom images, and 1 mm for in vivo patient cryotherapy and brachytherapy images. The mean execution time of needle segmentation algorithm was 2 s for a 3D TRUS image with size of 264 Multiplication-Sign 376 Multiplication-Sign 630 voxels. Conclusions

  10. Follow-up of coiled intracranial aneurysms: comparison of 3D time-of-flight and contrast-enhanced magnetic resonance angiography at 3T in a large, prospective series

    Pierot, Laurent [University of Reims, Department of Radiology, Maison Blanche Hospital, Reims (France); Hopital de la Maison Blanche - CHU, Service de radiologie, Reims (France); Portefaix, Christophe [University of Reims, Department of Radiology, Maison Blanche Hospital, Reims (France); University of Reims, CReSTIC SIC EA3804, Reims (France); Boulin, Anne [Foch Hospital, Department of Neuroradiology, Suresnes (France); Gauvrit, Jean-Yves [University of Rennes, Department of Radiology, CHU Rennes, Rennes (France)


    To compare 3D-TOF magnetic resonance angiography (MRA) and contrast-enhanced MRA (CE-MRA) sequences at 3T in the follow-up of coiled aneurysms with digital subtracted angiography (DSA) as the gold standard. DSA, 3D-TOF and CE-MRA were performed in a prospective series of 126 aneurysms in 96 patients (57 female, 39 male; age: 25-75 years, mean: 51.3 {+-} 11.3 years). The quality of aneurysm occlusion was assessed independently and anonymously by a core laboratory. Using DSA (gold standard technique), total occlusion was depicted in 57 aneurysms (45.2%), neck remnant in 34 aneurysms (27.0%) and aneurysm remnant in 35 aneurysms (27.8%). Sensitivity, specificity, positive predictive value and negative predictive value were very similar with 3D-TOF and CE-MRA. Visibility of coils was much better with 3D-TOF (95.2%) than with CE-MRA (23.0%) (P < 0.001). Also, substantial artefacts were less frequent with 3D-TOF (4.0%) than with CE-MRA (11.9%; P = 0.012). In this large prospective series of patients with coiled aneurysms, at 3T 3D-TOF MRA was equivalent to CE-MRA for the evaluation of aneurysm occlusion, but coil visibility was superior at 3D-TOF. Thus the use of 3D-TOF at 3T is recommended for the follow-up of coiled intracranial aneurysms. (orig.)

  11. 3D printing with RepRap cookbook

    Salinas, Richard


    A systematic guide consisting of over 100 recipes which focus on helping you understand the process of 3D printing using RepRap machines. The book aims at providing professionals with a series of working recipes to help make their fuzzy notions into real, saleable projects/objects using 3D printing technology. This book is for novice designers and artists who own a RepRap-based 3D printer, have fundamental knowledge of its working, and who desire to gain better mastery of the printing process. For the more experienced user, it will provide a handy visual resource, with side-by-side comparisons

  12. Nanoarchitectured 3D cathodes for Li-ion microbatteries

    Shaijumon, Manikoth M.; Perre, Emilie; Daffos, Barbara; Taberna, Pierre-Louis; Simon, Patrice [CIRIMAT, UMR CNRS 5085, Universite Paul Sabatier, 118 route de Narbonne, 31062 Toulouse Cedex 9 (France); Tarascon, Jean-Marie [LRCS UMR CNRS 6007, Universite de Picardie Jules Verne, 33 rue Saint Leu, 80039 Amiens (France)


    Microbatteries with large area capacity and no power limitation can be obtained by designing 3D structured batteries. 3D electrodes composed of 30 nm-thick films of LiCoO{sub 2} coating free-standing columns of Al current collector were achieved. By comparison with a planar electrode presenting an equivalent nominal capacity, a 3D electrode exhibits improved capacity retention: 68% of the nominal capacity at 8C instead of 11%. (Copyright copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. 3D medical thermography device

    Moghadam, Peyman


    In this paper, a novel handheld 3D medical thermography system is introduced. The proposed system consists of a thermal-infrared camera, a color camera and a depth camera rigidly attached in close proximity and mounted on an ergonomic handle. As a practitioner holding the device smoothly moves it around the human body parts, the proposed system generates and builds up a precise 3D thermogram model by incorporating information from each new measurement in real-time. The data is acquired in motion, thus it provides multiple points of view. When processed, these multiple points of view are adaptively combined by taking into account the reliability of each individual measurement which can vary due to a variety of factors such as angle of incidence, distance between the device and the subject and environmental sensor data or other factors influencing a confidence of the thermal-infrared data when captured. Finally, several case studies are presented to support the usability and performance of the proposed system.

  14. 3D Printable Graphene Composite

    Wei, Xiaojun; Li, Dong; Jiang, Wei; Gu, Zheming; Wang, Xiaojuan; Zhang, Zengxing; Sun, Zhengzong


    In human being’s history, both the Iron Age and Silicon Age thrived after a matured massive processing technology was developed. Graphene is the most recent superior material which could potentially initialize another new material Age. However, while being exploited to its full extent, conventional processing methods fail to provide a link to today’s personalization tide. New technology should be ushered in. Three-dimensional (3D) printing fills the missing linkage between graphene materials and the digital mainstream. Their alliance could generate additional stream to push the graphene revolution into a new phase. Here we demonstrate for the first time, a graphene composite, with a graphene loading up to 5.6 wt%, can be 3D printable into computer-designed models. The composite’s linear thermal coefficient is below 75 ppm·°C-1 from room temperature to its glass transition temperature (Tg), which is crucial to build minute thermal stress during the printing process.

  15. 3D printed bionic ears.

    Mannoor, Manu S; Jiang, Ziwen; James, Teena; Kong, Yong Lin; Malatesta, Karen A; Soboyejo, Winston O; Verma, Naveen; Gracias, David H; McAlpine, Michael C


    The ability to three-dimensionally interweave biological tissue with functional electronics could enable the creation of bionic organs possessing enhanced functionalities over their human counterparts. Conventional electronic devices are inherently two-dimensional, preventing seamless multidimensional integration with synthetic biology, as the processes and materials are very different. Here, we present a novel strategy for overcoming these difficulties via additive manufacturing of biological cells with structural and nanoparticle derived electronic elements. As a proof of concept, we generated a bionic ear via 3D printing of a cell-seeded hydrogel matrix in the anatomic geometry of a human ear, along with an intertwined conducting polymer consisting of infused silver nanoparticles. This allowed for in vitro culturing of cartilage tissue around an inductive coil antenna in the ear, which subsequently enables readout of inductively-coupled signals from cochlea-shaped electrodes. The printed ear exhibits enhanced auditory sensing for radio frequency reception, and complementary left and right ears can listen to stereo audio music. Overall, our approach suggests a means to intricately merge biologic and nanoelectronic functionalities via 3D printing.

  16. A Hybrid DE-RGSO-ELM for Brain Tumor Tissue Categorization in 3D Magnetic Resonance Images

    K. Kothavari


    Full Text Available Medical diagnostics, a technique used for visualizing the internal structures and functions of human body, serves as a scientific tool to assist physicians and involves direct use of digital imaging system analysis. In this scenario, identification of brain tumors is complex in the diagnostic process. Magnetic resonance imaging (MRI technique is noted to best assist tissue contrast for anatomical details and also carries out mechanisms for investigating the brain by functional imaging in tumor predictions. Considering 3D MRI model, analyzing the anatomy features and tissue characteristics of brain tumor is complex in nature. Henceforth, in this work, feature extraction is carried out by computing 3D gray-level cooccurence matrix (3D GLCM and run-length matrix (RLM and feature subselection for dimensionality reduction is performed with basic differential evolution (DE algorithm. Classification is performed using proposed extreme learning machine (ELM, with refined group search optimizer (RGSO technique, to select the best parameters for better simplification and training of the classifier for brain tissue and tumor characterization as white matter (WM, gray matter (GM, cerebrospinal fluid (CSF, and tumor. Extreme learning machine outperforms the standard binary linear SVM and BPN for medical image classifier and proves better in classifying healthy and tumor tissues. The comparison between the algorithms proves that the mean and standard deviation produced by volumetric feature extraction analysis are higher than the other approaches. The proposed work is designed for pathological brain tumor classification and for 3D MRI tumor image segmentation. The proposed approaches are applied for real time datasets and benchmark datasets taken from dataset repositories.

  17. Visual Semantic Based 3D Video Retrieval System Using HDFS.

    Kumar, C Ranjith; Suguna, S


    This paper brings out a neoteric frame of reference for visual semantic based 3d video search and retrieval applications. Newfangled 3D retrieval application spotlight on shape analysis like object matching, classification and retrieval not only sticking up entirely with video retrieval. In this ambit, we delve into 3D-CBVR (Content Based Video Retrieval) concept for the first time. For this purpose, we intent to hitch on BOVW and Mapreduce in 3D framework. Instead of conventional shape based local descriptors, we tried to coalesce shape, color and texture for feature extraction. For this purpose, we have used combination of geometric & topological features for shape and 3D co-occurrence matrix for color and texture. After thriving extraction of local descriptors, TB-PCT (Threshold Based- Predictive Clustering Tree) algorithm is used to generate visual codebook and histogram is produced. Further, matching is performed using soft weighting scheme with L2 distance function. As a final step, retrieved results are ranked according to the Index value and acknowledged to the user as a feedback .In order to handle prodigious amount of data and Efficacious retrieval, we have incorporated HDFS in our Intellection. Using 3D video dataset, we future the performance of our proposed system which can pan out that the proposed work gives meticulous result and also reduce the time intricacy.

  18. A new estimate of the global 3D geostrophic ocean circulation based on satellite data and in-situ measurements

    Mulet, S.; Rio, M.-H.; Mignot, A.; Guinehut, S.; Morrow, R.