Mary B. Vickerman

VESGEN 2D: automated, user-interactive software for quantification and mapping of angiogenic and lymphangiogenic trees and networks.

Quantification of microvascular remodeling as a meaningful discovery tool requires mapping and measurement of site‐specific changes within vascular trees and networks. Vessel density and other critical vascular parameters are often modulated by molecular regulators as determined by local vascular architecture. For example, enlargement of vessel diameter by vascular endothelial growth factor (VEGF) is restricted to specific generations of vessel branching (Parsons‐Wingerter et al., Microvascular Research72: 91, 2006). The averaging of vessel diameter over many successively smaller generations is therefore not particularly useful. The newly automated, user‐interactive software VESsel GENeration Analysis (VESGEN) quantifies major vessel parameters within two‐dimensional (2D) vascular trees, networks, and tree‐network composites. This report reviews application of VESGEN 2D to angiogenic and lymphangiogenic tissues that includes the human and murine retina, embryonic coronary vessels, and avian chorioallantoic membrane. Software output includes colorized image maps with quantification of local vessel diameter, fractal dimension, tortuosity, and avascular spacing. The density of parameters such as vessel area, length, number, and branch point are quantified according to site‐specific generational branching within vascular trees. The sole user input requirement is a binary (black/white) vascular image. Future applications of VESGEN will include analysis of 3D vascular architecture and bioinformatic dimensions such as blood flow and receptor localization. Branching analysis by VESGEN has demonstrated that numerous regulators including VEGF165, basic fibroblast growth factor, transforming growth factor β‐1, angiostatin and the clinical steroid triamcinolone acetonide induce ‘fingerprint’ or ‘signature’ changes in vascular patterning that provide unique readouts of dominant molecular signaling. Anat Rec, 292:320–332, 2009.

Selective Inhibition of Angiogenesis in Small Blood Vessels and Decrease in Vessel Diameter throughout the Vascular Tree by Triamcinolone Acetonide

PURPOSE To quantify the effects of the steroid triamcinolone acetonide (TA) on branching morphology within the angiogenic microvascular tree of the chorioallantoic membrane (CAM) of quail embryos. METHODS Increasing concentrations of TA (0-16 ng/mL) were applied topically on embryonic day (E) 7 to the chorioallantoic membrane (CAM) of quail embryos cultured in petri dishes and incubated for an additional 24 or 48 hours until fixation. Binary (black/white) microscopic images of arterial end points were quantified by generational analysis of vessel branching (VESGEN) software to obtain major vascular parameters that include vessel diameter (D(v)), fractal dimension (D(f)), tortuosity (T(v)), and densities of vessel area, length, number, and branch point (A(v), L(v), N(v), and Br(v)). For assessment of specific changes in vascular morphology induced by TA, the VESGEN software automatically segmented the vascular tree into branching generations (G(1)... G(10)) according to changes in vessel diameter and branching. RESULTS Vessel density decreased significantly up to 34% as the function of increasing concentration of TA according to A(v), L(v), Br(v), N(v), and D(f). TA selectively inhibited the growth of new, small vessels because L(v) decreased from 13.14 +/- 0.61 cm/cm(2) for controls to 8.012 +/- 0.82 cm/cm(2) at 16 ng TA/mL in smaller branching generations (G(7)-G(10)) and for N(v) from 473.83 +/- 29.85 cm(-2) to 302.32 +/- 33.09 cm(-2). In contrast, vessel diameter (D(v)) decreased throughout the vascular tree (G(1)-G(10)). CONCLUSIONS By VESGEN analysis, TA selectively inhibited the angiogenesis of smaller blood vessels, but decreased the vessel diameter of all vessels within the vascular tree.

Smagglce: Surface Modeling and Grid Generation for Iced Airfoils: Phase 1 Results

SmaggIce (Surface Modeling and Grid Generation for Iced Airfoils) is a software toolkit used in the process of aerodynamic performance prediction of iced airfoils with grid-based Computational Fluid Dynamics (CFD). It includes tools for data probing, boundary smoothing, domain decomposition, and structured grid generation and refinement. SmaggIce provides the underlying computations to perform these functions, a GUI (Graphical User Interface) to control and interact with those functions, and graphical displays of results, it is being developed at NASA Glenn Research Center. This paper discusses the overall design of SmaggIce as well as what has been implemented in Phase 1. Phase 1 results provide two types of software tools: interactive ice shape probing and interactive ice shape control. The ice shape probing tools will provide aircraft icing engineers and scientists with an interactive means to measure the physical characteristics of ice shapes. On the other hand, the ice shape control features of SmaggIce will allow engineers to examine input geometry data, correct or modify any deficiencies in the geometry, and perform controlled systematic smoothing to a level that will make the CFD process manageable.

Toward an Efficient Icing CFD Process Using an Interactive Software Toolkit--SmaggIce 2D

Two-dimensional CFD analysis for iced airfoils can be a labor-intensive task. The software toolkit SmaggIce 2D is being developed to help streamline the CFD process and provide the unique features needed for icing. When complete, it will include a combination of partially automated and fully interactive tools for all aspects of the tasks leading up to the flow analysis: geometry preparation, domain decomposition, block boundary discretization. gridding, and linking with a flow solver. It also includes tools to perform ice shape characterization, an important aid in determining the relationship between ice characteristics and their effects on aerodynamic performance. Completed tools, work-in-progress, and planned features of the software toolkit are presented here.

Oscillation of Angiogenesis with Vascular Dropout in Diabetic Retinopathy by VESsel GENeration Analysis (VESGEN)

PURPOSE Vascular dropout and angiogenesis are hallmarks of the progression of diabetic retinopathy (DR). However, current evaluation of DR relies on grading of secondary vascular effects, such as microaneurysms and hemorrhages, by clinical examination instead of by evaluation of actual vascular changes. The purpose of this study was to map and quantify vascular changes during progression of DR by VESsel GENeration Analysis (VESGEN). METHODS In this prospective cross-sectional study, 15 eyes with DR were evaluated with fluorescein angiography (FA) and color fundus photography, and were graded using modified Early Treatment Diabetic Retinopathy Study criteria. FA images were separated by semiautomatic image processing into arterial and venous trees. Vessel length density (L(v)), number density (N(v)), and diameter (D(v)) were analyzed in a masked fashion with VESGEN software. Each vascular tree was automatically segmented into branching generations (G(1)...G(8) or G(9)) by vessel diameter and branching. Vascular remodeling status (VRS) for N(v) and L(v) was graded 1 to 4 for increasing severity of vascular change. RESULTS By N(v) and L(v), VRS correlated significantly with the independent clinical diagnosis of mild to proliferative DR (13/15 eyes). N(v) and L(v) of smaller vessels (G(> or =6)) increased from VRS1 to VRS2 by 2.4 x and 1.6 x, decreased from VRS2 to VRS3 by 0.4 x and 0.6 x, and increased from VRS3 to VRS4 by 1.7 x and 1.5 x (P < 0.01). Throughout DR progression, the density of larger vessels (G(1-5)) remained essentially unchanged, and D(v1-5) increased slightly. CONCLUSIONS Vessel density oscillated with the progression of DR. Alternating phases of angiogenesis/neovascularization and vascular dropout were dominated first by remodeling of arteries and subsequently by veins.

SmaggIce 2.0: Additional Capabilities for Interactive Grid Generation of Iced Airfoils

The Surface Modeling and Grid Generation for Iced Airfoils (SmaggIce) software toolkit has been extended to allow interactive grid generation for multi-element iced airfoils. The essential phases of an icing effects study include geometry preparation, block creation and grid generation. SmaggIce Version 2.0 now includes these main capabilities for both single and multi-element airfoils, plus an improved flow solver interface and a variety of additional tools to enhance the efficiency and accuracy of icing effects studies. An overview of these features is given, especially the new multi-element blocking strategy using the multiple wakes method. Examples are given which illustrate the capabilities of SmaggIce for conducting an icing effects study for both single and multi-element airfoils.

A space-based end-to-end prototype geographic information network for lunar and planetary exploration and emergency response (2002 and 2003 field experiments)

Communications and imaging experiments conducted in the Arizona desert during July of 2002 with the National Aeronautics and Space Administration (NASA) and the United States Geological Survey (USGS) helped to identify a fundamental suite of scientific instruments focused on surface composition and temperature determination for the calibration and validation of NASA and USGS spaceborne and airborne sensors and to integrate them with a hybrid mobile wireless and satellite network for lunar and planetary exploration and emergency response. The 2002 experiment focused on the exchange of remotely sensed and ground truth geographic information between analysts and field scientists. That experiment revealed several modifications that would enhance the performance and effectiveness of geographic information networks (GIN) for lunar and planetary exploration and emergency response. Phase 2 experiments conducted during June 2003 at the USGS Earth Resources and Observation Systems (EROS) Data Centers geologic imaging test site near Dinosaur National Monument in the NE Utah desert incorporated several of the lessons learned from the 2002 experiment and successfully added five major new components: (1) near-real-time hyperspectral and multispectral satellite image acquisition, (2) remotely controlled and coordinated mobile real-time ground sensor measurements during the imaging satellite overpass, (3) long-delay optimized Transmission Control Protocol/Internet Protocol TCP/IP protocols to improve network performance over geosynchronous communications satellite circuits, (4) distributed, multinode parallel computing on NASAs Internet Power GRID (IPG), and (5) near-real-time validation of satellite imagery as part of a successful test of the NASA-USGS National Emergency Mapping Information System.

SmaggIce: Further Progress in Software for Gridding 2D Iced Airfoils

This paper presents progress being made in developing the SmaggIce software toolkit which is used to create structured grids for 2D iced airfoils in preparation for Computational Fluid Dynamics (CFD) analysis. A brief introduction is given which establishes the reasons for performing CFD analysis in icing research and the need for software to help with this. A short overview of a previously released version of SmaggIce (v1.2) is included. SmaggIce v1.2 includes tools for geometry preparation, a prerequisite task to performing gridding operations. Details of features added in the current version of SmaggIce (v1.8) are presented. These include tools for domain decomposition, block boundary modification, gridding, and grid quality display. Finally, plans are listed for the final version of SmaggIce (v2.0) which will include additional boundary modification tools and solution display.

An Aerodynamic Simulation Process for Iced Lifting Surfaces and Associated Issues

This paper discusses technologies and software tools that are being implemented in a software toolkit currently under development at NASA Glenn Research Center. Its purpose is to help study the effects of icing on airfoil performance and assist with the aerodynamic simulation process which consists of characterization and modeling of ice geometry, application of block topology and grid generation, and flow simulation. Tools and technologies for each task have been carefully chosen based on their contribution to the overall process. For the geometry characterization and modeling, we have chosen an interactive rather than automatic process in order to handle numerous ice shapes. An Appendix presents features of a software toolkit developed to support the interactive process. Approaches taken for the generation of block topology and grids, and flow simulation, though not yet implemented in the software, are discussed with reasons for why particular methods are chosen. Some of the issues that need to be addressed and discussed by the icing community are also included.