Three-Dimensional Computerized Anthropometry of the Nose: Landmark Representation Compared to Surface Analysis

2007 ◽  
Vol 44 (3) ◽  
pp. 278-285 ◽  
Author(s):  
Virgilio F. Ferrario ◽  
Fabrizio Mian ◽  
Redento Peretta ◽  
Riccardo Rosati ◽  
Chiarella Sforza
Keyword(s):  
Three Dimensional ◽  
Digital Data ◽  
Limits Of Agreement ◽  
B Splines ◽  
Surface Areas ◽  
Using Data ◽  
Difference Volume ◽  
T Values ◽  
Plaster Models ◽  
Plaster Casts

Objective: To compare three-dimensional nasal measurements directly made on subjects to those made on plaster casts, and nasal dimensions obtained with a surface-based approach to values obtained with a landmark representation. Methods: Soft-tissue nasal landmarks were directly digitized on 20 healthy adults. Stone casts of their noses were digitized and mathematically reconstructed using nonuniform rational B-splines (NURBS) curves. Linear distances, angles, volumes and surface areas were computed using facial landmarks and NURBS-reconstructed models (surface-based approach). Results: Measurements on the stone casts were somewhat smaller than values obtained directly from subjects (differences between −0.05 and −1.58 mm). Dahlberg's statistic ranged between 0.73 and 1.47 mm. Significant (p < .05) t values were found for 4 of 15 measurements. The surface-based approach gave values 3.5 (volumes) and 2.1 (surface area) times larger than those computed with the landmark-based method. The two values were significantly related (volume, r = 0.881; surface, r = 0.924; p < .001), the resulting equations estimated actual values well (mean difference, volume −0.01 mm3, SD 1.47, area 0.05 cm2, SD 1.44); limits of agreement between −2.89 and 2.87 mm3 (volume); −2.88 and 2.78 cm2 (area). Conclusions: Considering the characteristics of the two methods, and for practical purposes, nasal distances and angles obtained on plaster models were comparable to digital data obtained directly from subjects. Surface areas and volumes were best obtained using a surface-based approach, but could be estimated using data provided by the landmark representation.

scholarly journals Accuracy of three-dimensional dental resin models created by fused deposition modeling, stereolithography, and Polyjet prototype technologies: A comparative study

2018 ◽  
Vol 88 (3) ◽  
pp. 363-369 ◽  
Author(s):  
Raymund E. Rebong ◽  
Kelton T. Stewart ◽  
Achint Utreja ◽  
Ahmed A. Ghoneima
Keyword(s):  
Fused Deposition Modeling ◽  
Three Dimensional ◽  
Vertical Plane ◽  
Physical Models ◽  
Dental Resin ◽  
Fused Deposition ◽  
Deposition Modeling ◽  
School Of Dentistry ◽  
Plaster Models ◽  
Plaster Casts

ABSTRACT Objectives: The aim of this study was to assess the dimensional accuracy of fused deposition modeling (FDM)–, Polyjet-, and stereolithography (SLA)–produced models by comparing them to traditional plaster casts. Materials and A total of 12 maxillary and mandibular posttreatment orthodontic plaster casts were selected from the archives of the Orthodontic Department at the Indiana University School of Dentistry. Plaster models were scanned, saved as stereolithography files, and printed as physical models using three different three-dimensional (3D) printers: Makerbot Replicator (FDM), 3D Systems SLA 6000 (SLA), and Objet Eden500V (Polyjet). A digital caliper was used to obtain measurements on the original plaster models as well as on the printed resin models.Methods: Results: Comparison between the 3D printed models and the plaster casts showed no statistically significant differences in most of the parameters. However, FDM was significantly higher on average than were plaster casts in maxillary left mixed plane (MxL-MP) and mandibular intermolar width (Md-IMW). Polyjet was significantly higher on average than were plaster casts in maxillary intercanine width (Mx-ICW), mandibular intercanine width (Md-ICW), and mandibular left mixed plane (MdL-MP). Polyjet was significantly lower on average than were plaster casts in maxillary right vertical plane (MxR-vertical), maxillary left vertical plane (MxL-vertical), mandibular right anteroposterior plane (MdR-AP), mandibular right vertical plane (MdR-vertical), and mandibular left vertical plane (MdL-vertical). SLA was significantly higher on average than were plaster casts in MxL-MP, Md-ICW, and overbite. SLA was significantly lower on average than were plaster casts in MdR-vertical and MdL-vertical. Conclusions: Dental models reconstructed by FDM technology had the fewest dimensional measurement differences compared to plaster models.

scholarly journals Improvement on Permeability of Cyclic Peptide/Peptidomimetic: Backbone N-Methylation as A Useful Tool

Marine Drugs ◽  
2021 ◽  
Vol 19 (6) ◽  
pp. 311
Author(s):  
Yang Li ◽  
Wang Li ◽  
Zhengshuang Xu
Keyword(s):  
Cyclic Peptides ◽  
Cyclic Peptide ◽  
Three Dimensional ◽  
Conformational Space ◽  
Cell Permeability ◽  
Relative Importance ◽  
Intrinsic Properties ◽  
Surface Areas ◽  
Synthetic Methodologies ◽  
Three Dimensional Configuration

Peptides have a three-dimensional configuration that can adopt particular conformations for binding to proteins, which are well suited to interact with larger contact surface areas on target proteins. However, low cell permeability is a major challenge in the development of peptide-related drugs. In recent years, backbone N-methylation has been a useful tool for manipulating the permeability of cyclic peptides/peptidomimetics. Backbone N-methylation permits the adjustment of molecule’s conformational space. Several pathways are involved in the drug absorption pathway; the relative importance of each N-methylation to total permeation is likely to differ with intrinsic properties of cyclic peptide/peptidomimetic. Recent studies on the permeability of cyclic peptides/peptidomimetics using the backbone N-methylation strategy and synthetic methodologies will be presented in this review.

Facial reconstruction project

1970 ◽  
Vol 80 (1) ◽  
Author(s):  
Federico Cesarani ◽  
Maria Cristina Martina ◽  
Valter Capussotto ◽  
Andrea Giuliano ◽  
Renato Grilletto ◽  
...  
Keyword(s):  
3D Model ◽  
Multidetector Ct ◽  
Three Dimensional ◽  
Facial Reconstruction ◽  
Digital Data ◽  
Egyptian Mummy ◽  
Ancient Egyptian ◽  
Synthetic Materials ◽  
Reconstruction Project

Facial reconstruction of mummies and corpses is important in anthropological, medical and forensic studies. The purpose of our study was to evaluate the role of three- Dimensional Multidetector CT examination for 3D facial reconstruction. We present a multidisciplinary work performed by radiologists, anthropologists and forensic police in reconstructing the possible physiognomy of an ancient Egyptian mummy. Three-Dimensional data were obtained from a well-preserved completely wrapped Egyptian mummy from the collection of the Egyptian Museum in Torino, Italy, dated from XXII or XXIII dynasty (945-715 BC). Data were used as a model for the rapid prototyping stereolithographic technique, a method which allows the creation of 3D model with digital data using synthetic materials such as resin or nylon.

scholarly journals Synthesis, Characterization and Photocatalytic Activity of Nanocrystalline First Transition-Metal (Ti, Mn, Co, Ni and Zn) Oxisde Nanofibers by Electrospinning

2018 ◽  
Vol 9 (1) ◽  
pp. 8 ◽  
Author(s):  
Yu Chen ◽  
Weipeng Lu ◽  
Yanchuan Guo ◽  
Yi Zhu ◽  
Haojun Lu ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Transition Metal ◽  
Metal Oxide ◽  
Specific Surface ◽  
Three Dimensional ◽  
Photogenerated Electron ◽  
Practical Applications ◽  
Surface Areas ◽  
Tio2 Nanofiber ◽  
Transmission Electron

In this work, five nanocrystalline first transition-metal (Ti, Mn, Co, Ni and Zn) oxide nanofibers were prepared by electrospinning and controlled calcination. The morphology, crystal structure, pore size distribution and specific surface area were systematically studied by scanning electron microscope (SEM), transmission electron microscope (TEM), surface and pore analysis, and thermo gravimetric analyzer (TGA). The results reveal that the obtained nanofibers have a continuously twisted three-dimensional scaffold structure and are composed of neat nanocrystals with a necklace-like arrangement. All the samples possess high specific surface areas, which follow the order of NiO nanofiber (393.645 m2/g) > TiO2 nanofiber (121.445 m2/g) > ZnO nanofiber (57.219 m2/g) > Co3O4 nanofiber (52.717 m2/g) > Mn2O3 nanofiber (18.600 m2/g). Moreover, the photocatalytic degradation of methylene blue (MB) in aqueous solution was investigated in detail by employing the five kinds of metal oxide nanofibers as photocatalysts under ultraviolet (UV) irradiation separately. The results show that ZnO, TiO2 and NiO nanofibers exhibit excellent photocatalytic efficiency and high cycling ability to MB, which may be ascribed to unique porous structures and the highly efficient separation of photogenerated electron-hole pairs. In brief, this paper aims to provide a feasible approach to achieve five first transition-metal oxide nanofibers with excellent performance, which is important for practical applications.

scholarly journals Dynamics of Three-Dimensional Turbulent Wall Plumes and Implications for Estimates of Submarine Glacier Melting

2018 ◽  
Vol 48 (9) ◽  
pp. 1941-1950 ◽  
Author(s):  
Ekaterina Ezhova ◽  
Claudia Cenedese ◽  
Luca Brandt
Keyword(s):  
Three Dimensional ◽  
Characteristic Parameters ◽  
Buoyant Plumes ◽  
Tidewater Glaciers ◽  
Glacier Melting ◽  
Order Of Magnitude ◽  
Layer Flow ◽  
Using Data ◽  
Turbulent Wall ◽  
Wall Plume

AbstractSubglacial discharges have been observed to generate buoyant plumes along the ice face of Greenland tidewater glaciers. These plumes have been traditionally modeled using classical plume theory, and their characteristic parameters (e.g., velocity) are employed in the widely used three-equation melt parameterization. However, the applicability of plume theory for three-dimensional turbulent wall plumes is questionable because of the complex near-wall plume dynamics. In this study, corrections to the classical plume theory are introduced to account for the presence of a wall. In particular, the drag and entrainment coefficients are quantified for a three-dimensional turbulent wall plume using data from direct numerical simulations. The drag coefficient is found to be an order of magnitude larger than that for a boundary layer flow over a flat plate at a similar Reynolds number. This result suggests a significant increase in the melting estimates by the current parameterization. However, the volume flux in a wall plume is found to be one-half that of a conical plume that has 2 times the buoyancy flux. This finding suggests that the total entrainment (per unit area) of ambient water is the same and that the plume scalar characteristics (i.e., temperature and salinity) can be predicted reasonably well using classical plume theory.

Did They Mind the Gap? Voter/Party Ideological Proximity between the BQ, the NDP and Quebec Voters, 2006–2011

2016 ◽  
Vol 49 (2) ◽  
pp. 289-310 ◽  
Author(s):  
Jean-Philippe Gauvin ◽  
Chris Chhim ◽  
Mike Medeiros
Keyword(s):  
Political Party ◽  
Three Dimensional ◽  
Election Study ◽  
Federal Election ◽  
Party Manifestos ◽  
Longitudinal Approach ◽  
The Face ◽  
Election Results ◽  
Using Data ◽  
Over Time

AbstractThe 2011 Canadian federal election results changed the face of federal politics in Quebec. In a sudden and spectacular reversal of electoral fortunes, BQ support crumbled while that of the NDP surged. While most commentators focused exclusively on the 2011 election itself to explain what had happened, we offer an interpretation that takes a longitudinal approach. Using data from the Canadian Election Study and political party manifestos from 2006 to 2011, we propose a three-dimensional proximity model of voter/party congruence to explore the evolution of the ideological stances of Quebec voters and parties. Empirical results suggest these ideological distances between the NDP and Quebec voters decreased over time, whereas the BQ has distanced itself from voters. Furthermore, ideological distances between party and voters are a significant predictor of vote.

scholarly journals Data assimilation for volcanic ash plumes using a satellite observational operator: a case study on the 2010 Eyjafjallajökull volcanic eruption

2017 ◽  
Vol 17 (2) ◽  
pp. 1187-1205 ◽  
Author(s):  
Guangliang Fu ◽  
Fred Prata ◽  
Hai Xiang Lin ◽  
Arnold Heemink ◽  
Arjo Segers ◽  
...  
Keyword(s):  
Data Assimilation ◽  
Volcanic Ash ◽  
Three Dimensional ◽  
Forecast Accuracy ◽  
Improve Model ◽  
Powerful Approach ◽  
Using Data ◽  
D Model

Abstract. Using data assimilation (DA) to improve model forecast accuracy is a powerful approach that requires available observations. Infrared satellite measurements of volcanic ash mass loadings are often used as input observations for the assimilation scheme. However, because these primary satellite-retrieved data are often two-dimensional (2-D) and the ash plume is usually vertically located in a narrow band, directly assimilating the 2-D ash mass loadings in a three-dimensional (3-D) volcanic ash model (with an integral observational operator) can usually introduce large artificial/spurious vertical correlations.In this study, we look at an approach to avoid the artificial vertical correlations by not involving the integral operator. By integrating available data of ash mass loadings and cloud top heights, as well as data-based assumptions on thickness, we propose a satellite observational operator (SOO) that translates satellite-retrieved 2-D volcanic ash mass loadings to 3-D concentrations. The 3-D SOO makes the analysis step of assimilation comparable in the 3-D model space.Ensemble-based DA is used to assimilate the extracted measurements of ash concentrations. The results show that satellite DA with SOO can improve the estimate of volcanic ash state and the forecast. Comparison with both satellite-retrieved data and aircraft in situ measurements shows that the effective duration of the improved volcanic ash forecasts for the distal part of the Eyjafjallajökull volcano is about 6 h.

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