Three dimensional measurements of surface areas and burning velocities of turbulent spherical flames

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.

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

Marine Drugs ◽

10.3390/md19060311 ◽

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.

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Atomic force microscope cantilever based microcoordinate measuring probe for true three-dimensional measurements of microstructures

Applied Physics Letters ◽

10.1063/1.2786881 ◽

2007 ◽

Vol 91 (12) ◽

pp. 121912 ◽

Cited By ~ 15

Author(s):

Gaoliang Dai ◽

Helmut Wolff ◽

Hans-Ulrich Danzebrink

Keyword(s):

Atomic Force Microscope ◽

Three Dimensional ◽

Atomic Force Microscope Cantilever ◽

Atomic Force ◽

Measuring Probe ◽

Dimensional Measurements ◽

Force Microscope Cantilever

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IMG-07. GADOLINIUM IS NOT NECESSARY FOR SURVEILLANCE MR IMAGING IN CHILDREN WITH CHIASMATIC-HYPOTHALAMIC LOW GRADE GLIOMA

Neuro-Oncology ◽

10.1093/neuonc/noaa222.343 ◽

2020 ◽

Vol 22 (Supplement_3) ◽

pp. iii356-iii356

Author(s):

Fatema Malbari ◽

Murali Chintagumpala ◽

Jack Su ◽

Mehmet Okcu ◽

Frank Lin ◽

...

Keyword(s):

Metastatic Disease ◽

Three Dimensional ◽

Low Grade Glioma ◽

Cancer Center ◽

Low Grade ◽

Contrast Imaging ◽

Post Contrast ◽

Best Response ◽

Dimensional Measurements ◽

Initiation Of Therapy

Abstract BACKGROUND Patients with chiasmatic-hypothalamic low grade glioma (CHLGG) have frequent MRIs with gadolinium based contrast agents (GBCA) for disease monitoring. Cumulative gadolinium deposition in children is a potential concern. The purpose of this research is to establish whether MRI with GBCA is necessary for determining tumor progression in children with CHLGG. METHODS Children with progressive CHLGG were identified from Texas Children’s Cancer Center between 2005–2019. Pre- and post-contrast MRI sequences were separately reviewed by one neuroradiologist who was blinded to the clinical course. Three dimensional measurements and tumor characteristics were collected. Radiographic progression was defined as a 25% increase in size (product of two largest dimensions) compared to baseline or best response after initiation of therapy. RESULTS A total of 28 patients with progressive CHLGG including 683 MRIs with GBCA (mean 24 MRIs/patient; range: 10–43 MRIs) were reviewed. No patients had a diagnosis of NF1. Progression was observed 92 times, 91 (98.9%) on noncontrast and 90 (97.8%) on contrast imaging. Sixty-seven radiographic and/or clinical progressions necessitating management changes were identified in all (100%) noncontrast sequences and 66 (98.5%) contrast sequences. Tumor growth >2 mm in any dimension was identified in 184/187(98.4%) on noncontrast and 181/187(96.8%) with contrast imaging. Non primary metastatic disease was seen in seven patients (25%), which were better visualized on contrast imaging in 4 (57%). CONCLUSION MRI without GBCA effectively identifies patients with progressive disease. One should consider eliminating contrast in imaging of children with CHLGG with GBCA reserved for monitoring those with metastatic disease.

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

Applied Sciences ◽

10.3390/app9010008 ◽

2018 ◽

Vol 9 (1) ◽

pp. 8 ◽

Cited By ~ 5

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.

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