@article{sohn_kibbe_dioli_hector_bai_garrard_muddiman_2024, title={A statistical approach to system suitability testing for mass spectrometry imaging}, volume={38}, ISSN={["1097-0231"]}, DOI={10.1002/rcm.9725}, abstractNote={RationaleMass spectrometry imaging (MSI) elevates the power of conventional mass spectrometry (MS) to multidimensional space, elucidating both chemical composition and localization. However, the field lacks any robust quality control (QC) and/or system suitability testing (SST) protocols to monitor inconsistencies during data acquisition, both of which are integral to ensure the validity of experimental results. To satisfy this demand in the community, we propose an adaptable QC/SST approach with five analyte options amendable to various ionization MSI platforms (e.g., desorption electrospray ionization, matrix‐assisted laser desorption/ionization [MALDI], MALDI‐2, and infrared matrix‐assisted laser desorption electrospray ionization [IR‐MALDESI]).}, number={9}, journal={RAPID COMMUNICATIONS IN MASS SPECTROMETRY}, author={Sohn, Alexandria L. and Kibbe, Russell R. and Dioli, Olivia E. and Hector, Emily C. and Bai, Hongxia and Garrard, Kenneth P. and Muddiman, David C.}, year={2024}, month={May} }
 @article{xi_knizner_garrard_muddiman_2023, title={Automatic z-Axis Correction for IR-MALDESI Mass Spectrometry Imaging of Uneven Surfaces}, volume={6}, ISSN={["1879-1123"]}, DOI={10.1021/jasms.3c00151}, abstractNote={Two-dimensional mass spectrometry imaging (2D MSI) experiments mainly involve samples with a flat surface and constant thickness, but some samples are challenging to section due to the texture and topography. Herein, we present an MSI method that automatically corrects for discernible height differences across surfaces during imaging experiments. A chromatic confocal sensor was incorporated into the infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) system to measure the sample surface height at the location of each analytical scan. The height profile is subsequently used for adjusting the z-axis position of the sample during MSI data acquisition. We evaluated this method using a tilted mouse liver section and an unsectioned Prilosec tablet due to their exterior quasi-homogeneity and height differences of approximately ∼250 μm. MSI with automatic z-axis correction showed consistent ablated spot sizes and shapes, revealing the measured ion spatial distribution across a mouse liver section and a Prilosec tablet. Conversely, irregular spots and reduced signals with large variability were observed when no z-axis correction was applied.}, journal={JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY}, author={Xi, Ying and Knizner, Kevan T. T. and Garrard, Kenneth P. P. and Muddiman, David C. C.}, year={2023}, month={Jun} }
 @article{joignant_ritter_knizner_garrard_kullman_muddiman_2023, title={Maximized Spatial Information and Minimized Acquisition Time of Top-Hat IR-MALDESI-MSI of Zebrafish Using Nested Regions of Interest (nROIs)}, volume={8}, ISSN={["1879-1123"]}, DOI={10.1021/jasms.3c00210}, abstractNote={Increasing the spatial resolution of a mass spectrometry imaging (MSI) method results in a more defined heatmap of the spatial distribution of molecules across a sample, but it is also associated with the disadvantage of increased acquisition time. Decreasing the area of the region of interest to achieve shorter durations results in the loss of potentially valuable information in larger specimens. This work presents a novel MSI method to reduce the time of MSI data acquisition with variable step size imaging: nested regions of interest (nROIs). Using nROIs, a small ROI may be imaged at a higher spatial resolution while nested inside a lower-spatial-resolution peripheral ROI. This conserves the maximal spatial and chemical information generated from target regions while also decreasing the necessary acquisition time. In this work, the nROI method was characterized on mouse liver and applied to top-hat MSI of zebrafish using a novel optical train, which resulted in a significant improvement in both acquisition time and spatial detail of the zebrafish. The nROI method can be employed with any step size pairing and adapted to any method in which the acquisition time of larger high-resolution ROIs poses a practical challenge.}, journal={JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY}, author={Joignant, Alena N. and Ritter, Morgan M. and Knizner, Kevan T. and Garrard, Kenneth P. and Kullman, Seth W. and Muddiman, David C.}, year={2023}, month={Aug} }
 @article{arciniega_garrard_guymon_manni sr_apffel_fjeldsted_muddiman_2023, title={Quasi-continuous infrared matrix-assisted laser desorption electrospray ionization source coupled to a quadrupole time-of-flight mass spectrometer for direct analysis from well plates}, volume={58}, ISSN={["1096-9888"]}, DOI={10.1002/jms.4902}, abstractNote={Abstract}, number={1}, journal={JOURNAL OF MASS SPECTROMETRY}, author={Arciniega, Cristina and Garrard, Kenneth P. and Guymon, Jacob P. and Manni Sr, Jeffrey G. and Apffel, Alex and Fjeldsted, John C. and Muddiman, David C.}, year={2023}, month={Jan} }
 @article{joignant_bai_guymon_garrard_pankow_muddiman_2022, title={Developing transmission mode for infrared matrix-assisted laser desorption electrospray ionization mass spectrometry imaging}, volume={36}, ISSN={["1097-0231"]}, DOI={10.1002/rcm.9386}, abstractNote={RationaleThe development and characterization of the novel NextGen infrared matrix‐assisted laser desorption electrospray ionization (IR‐MALDESI) source catalyzed new advancements in IR‐MALDESI instrumentation, including the development of a new analysis geometry.}, number={22}, journal={RAPID COMMUNICATIONS IN MASS SPECTROMETRY}, author={Joignant, Alena N. and Bai, Hongxia and Guymon, Jacob P. and Garrard, Kenneth P. and Pankow, Mark and Muddiman, David C.}, year={2022}, month={Nov} }
 @article{kalmar_garrard_muddiman_2021, title={GlycoHunter: An Open-Source Software for the Detection and Relative Quantification of INLIGHT-Labeled N-Linked Glycans}, volume={20}, ISSN={["1535-3907"]}, DOI={10.1021/acs.jproteome.0c00840}, abstractNote={Glycans are responsible for many biological activities; however, their structures are incredibly diverse and complex, often rendering the field of glycomics unsolvable by a single analytical technique. The development of multiple chemical derivatization strategies and bioinformatic software is responsible for some of the greatest analytical gains in the field of glycomics. The INLIGHT strategy is a chemical derivatization technique using hydrazide chemistry to derivatize the reducing end of N-linked glycans and incorporates either a natural (NAT, 12C6) or a stable-isotope label (SIL, 13C6) to carry out relative quantification. Here we present GlycoHunter, a user-friendly software created in MATLAB that enables researchers to accurately and efficiently process MS1 glycomics data where a NAT and SIL pair is generated for relative quantification, including but not limited to, INLIGHT. GlycoHunter accepts the commonly used data file formats imzML and mzXML and effectively identifies all peak pairs associated with NAT- and SIL-labeled N-linked glycans using MS1 data. It also includes the ability to tailor the search parameters and export the results for further analysis using Skyline or Excel.}, number={4}, journal={JOURNAL OF PROTEOME RESEARCH}, author={Kalmar, Jaclyn Gowen and Garrard, Kenneth P. and Muddiman, David C.}, year={2021}, month={Apr}, pages={1855–1863} }
 @article{tu_garrard_said_muddiman_2021, title={In situ detection of fatty acid C=C positional isomers by coupling on-tissue mCPBA epoxidation with infrared matrix-assisted laser desorption electrospray ionization mass spectrometry}, volume={35}, ISSN={["1097-0231"]}, DOI={10.1002/rcm.9119}, abstractNote={RationaleUnsaturated fatty acids (UFAs) play vital roles in regulating cellular functions. In‐depth structural characterization of UFAs such as localizing carbon–carbon double bonds is fundamentally important but poses considerable challenges in mass spectrometry (MS) given that the most widely accessible ion activation method, low‐energy collision‐induced dissociation (CID), primarily generates uninformative fragments (e.g., neutral loss of CO2) that are not suggestive of the double‐bond positions.}, number={13}, journal={RAPID COMMUNICATIONS IN MASS SPECTROMETRY}, author={Tu, Anqi and Garrard, Kenneth P. and Said, Neveen and Muddiman, David C.}, year={2021}, month={Jul} }
 @article{knuth_stutts_ritter_garrard_kullman_2021, title={Vitamin D deficiency promotes accumulation of bioactive lipids and increased endocannabinoid tone in zebrafish}, volume={62}, ISSN={["1539-7262"]}, url={https://doi.org/10.1016/j.jlr.2021.100142}, DOI={10.1016/j.jlr.2021.100142}, abstractNote={Vitamin D is well known for its traditional role in bone mineral homeostasis; however, recent evidence suggests that vitamin D also plays a significant role in metabolic control. This study served to investigate putative linkages between vitamin D deficiency (VDD) and metabolic disruption of bioactive lipids by MS imaging. Our approach employed infrared-matrix-assisted laser desorption electrospray ionization MS imaging for lipid metabolite profiling in 6-month-old zebrafish fed either a VDD or a vitamin D-sufficient (VDS) diet. Using a lipidomics pipeline, we found that VDD zebrafish had a greater abundance of bioactive lipids (N-acyls, endocannabinoids [ECs], diacylglycerols/triacylglycerols, bile acids/bile alcohols, and vitamin D derivatives) suggestive of increased EC tone compared with VDS zebrafish. Tandem MS was performed on several differentially expressed metabolites with sufficient ion abundances to aid in structural elucidation and provide additional support for MS annotations. To confirm activation of the EC pathways, we subsequently examined expression of genes involved in EC biosynthesis, metabolism, and receptor signaling in adipose tissue and liver from VDD and VDS zebrafish. Gene expression changes were congruent with increased EC tone, with VDD zebrafish demonstrating increased synthesis and metabolism of anandamide compared with VDS zebrafish. Taken together, our data suggest that VDD may promote accumulation of bioactive lipids and increased EC tone in zebrafish.}, journal={JOURNAL OF LIPID RESEARCH}, publisher={Elsevier BV}, author={Knuth, Megan M. and Stutts, Whitney L. and Ritter, Morgan M. and Garrard, Kenneth P. and Kullman, Seth W.}, year={2021} }
 @article{garrard_ekelöf_khodjaniyazova_bagley_muddiman_2020, title={A Versatile Platform for Mass Spectrometry Imaging of Arbitrary Spatial Patterns}, volume={31}, ISSN={1044-0305 1879-1123}, url={http://dx.doi.org/10.1021/jasms.0c00128}, DOI={10.1021/jasms.0c00128}, abstractNote={A vision-system driven platform, RastirX, has been constructed for mass spectrometry imaging (MSI) of arbitrary two-dimensional patterns. The user identifies a region of interest (ROI) by drawing on a live video image of the sample with the computer mouse. Motion commands are automatically generated to move the sample to acquire scan data for the pixels in the ROI. Synchronization of sample stage motion with laser firing and mass spectrometer (MS) scan acquisition is fully automated. RastirX saves a co-registered optical image and the scan location information needed to convert raw MS data into imzML format. Imaging an arbitrarily shaped ROI instead of the minimal enclosing rectangle reduces contamination from off-sample material and significantly reduces acquisition time.}, number={12}, journal={Journal of the American Society for Mass Spectrometry}, publisher={American Chemical Society (ACS)}, author={Garrard, Kenneth P. and Ekelöf, Måns and Khodjaniyazova, Sitora and Bagley, M. Caleb and Muddiman, David C.}, year={2020}, month={Jun}, pages={2547–2552} }
 @article{bai_khodjaniyazova_garrard_muddiman_2020, title={Three-Dimensional Imaging with Infrared Matrix-Assisted Laser Desorption Electrospray Ionization Mass Spectrometry}, volume={31}, ISSN={["1879-1123"]}, DOI={10.1021/jasms.9b00066}, abstractNote={Mass spectrometry imaging as a field has pushed its frontiers to three dimensions. Most three-dimensional mass spectrometry imaging (3D MSI) approaches require serial sectioning that results in a loss of biological information between analyzed slices and difficulty in reconstruction of 3D images. In this contribution, infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) was demonstrated to be applicable for 3D MSI that does not require sectioning because IR laser ablates material on a micrometer scale. A commercially available over-the-counter pharmaceutical was used as a model to demonstrate the feasibility of IR-MALDESI for 3D MSI. Depth resolution (i.e., z-resolution) as a function of laser energy levels and density of ablated material was investigated. The best achievable depth resolution from a pill was 2.3 μm at 0.3 mJ/pulse. 2D and 3D MSI were performed on the tablet to show the distribution of pill-specific molecules. A 3D MSI analysis on a region of interest of 15 × 15 voxels across 50 layers was performed. Our results demonstrate that IR-MALDESI is feasible with 3D MSI on a pill, and future work will be focused on analyses of biological tissues.}, number={2}, journal={JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY}, author={Bai, Hongxia and Khodjaniyazova, Sitora and Garrard, Kenneth P. and Muddiman, David}, year={2020}, month={Feb}, pages={292–297} }
 @article{ekelöf_garrard_judd_rosen_xie_kashuba_muddiman_2018, title={Evaluation of Digital Image Recognition Methods for Mass Spectrometry Imaging Data Analysis}, volume={29}, ISSN={1044-0305 1879-1123}, url={http://dx.doi.org/10.1007/S13361-018-2073-0}, DOI={10.1007/s13361-018-2073-0}, abstractNote={Analyzing mass spectrometry imaging data can be laborious and time consuming, and as the size and complexity of datasets grow, so does the need for robust automated processing methods. We here present a method for comprehensive, semi-targeted discovery of molecular distributions of interest from mass spectrometry imaging data, using widely available image similarity scoring algorithms to rank images by spatial correlation. A fast and powerful batch search method using a MATLAB implementation of structural similarity (SSIM) index scoring with a pre-selected reference distribution is demonstrated for two sample imaging datasets, a plant metabolite study using Artemisia annua leaf, and a drug distribution study using maraviroc-dosed macaque tissue. Graphical Abstract ᅟ.}, number={12}, journal={Journal of The American Society for Mass Spectrometry}, publisher={Springer Science and Business Media LLC}, author={Ekelöf, Måns and Garrard, Kenneth P. and Judd, Rika and Rosen, Elias P. and Xie, De-Yu and Kashuba, Angela D. M. and Muddiman, David C.}, year={2018}, month={Oct}, pages={2467–2470} }
 @article{bodlapati_dow_wong_garrard_2018, title={Surface Finish and Diamond Tool Wear when machining PMMA and PC Optics}, volume={10742}, ISSN={["1996-756X"]}, DOI={10.1117/12.2319683}, abstractNote={Optical devices are extremely important since they play a critical role in optical recording and display. Single point diamond turning is one of the most common methods to create plastic optics. Diamond turning of plastics is influenced by a wide variety of factors such as the glass transition temperature of the polymer, other material properties and operator controlled cutting conditions. Since diamond is one of the hardest materials in nature and polymers are relatively soft, little tool wear is expected. But the optics industry claims that tool wear is a major problem. Most of the optical industry uses Poly (methyl methacrylate) (PMMA) and Polycarbonate (PC) for creating optics. The objective of this research is to optimize machining parameters (such as feed, depth of cut, cutting speed and rake angle) to produce optical surface quality (RMS Surface finish < 10 nm) while minimizing tool wear for the two materials. A wide range of experiments were performed on the two materials by varying machining parameters and measuring worn tools using the Electron Beam Induced Deposition (EBID) technique in the Scanning Electron Microscope (SEM). In the experimental conditions used, PMMA was found to have better surface finish than PC when machined with a zero-rake angle diamond tool. Polycarbonate was found to wear the tool more than PMMA under similar cutting conditions. It was also found that Polycarbonate is more sensitive to chip management and chip geometry than PMMA. Detailed effects of all machining parameters for the two materials were studied.}, journal={OPTICAL MANUFACTURING AND TESTING XII}, author={Bodlapati, Charan and Dow, Thomas and Wong, Anthony and Garrard, Ken}, year={2018} }
 @article{bokhart_manni_garrard_ekelöf_nazari_muddiman_2017, title={IR-MALDESI Mass Spectrometry Imaging at 50 Micron Spatial Resolution}, volume={28}, ISSN={1044-0305 1879-1123}, url={http://dx.doi.org/10.1007/S13361-017-1740-X}, DOI={10.1007/s13361-017-1740-x}, abstractNote={High spatial resolution in mass spectrometry imaging (MSI) is crucial to understanding the biology dictated by molecular distributions in complex tissue systems. Here, we present MSI using infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) at 50 μm resolution. An adjustable iris, beam expander, and an aspherical focusing lens were used to reduce tissue ablation diameters for MSI at high resolution. The laser beam caustic was modeled using laser ablation paper to calculate relevant laser beam characteristics. The minimum laser spot diameter on the tissue was determined using tissue staining and microscopy. Finally, the newly constructed optical system was used to image hen ovarian tissue with and without oversampling, detailing tissue features at 50 μm resolution. Graphical Abstract ᅟ.}, number={10}, journal={Journal of The American Society for Mass Spectrometry}, publisher={Springer Nature}, author={Bokhart, Mark T. and Manni, Jeffrey and Garrard, Kenneth P. and Ekelöf, Måns and Nazari, Milad and Muddiman, David C.}, year={2017}, month={Jul}, pages={2099–2107} }
 @article{bokhart_nazari_garrard_muddiman_2017, title={MSiReader v1.0: Evolving Open-Source Mass Spectrometry Imaging Software for Targeted and Untargeted Analyses}, volume={29}, ISSN={1044-0305 1879-1123}, url={http://dx.doi.org/10.1007/S13361-017-1809-6}, DOI={10.1007/s13361-017-1809-6}, abstractNote={A major update to the mass spectrometry imaging (MSI) software MSiReader is presented, offering a multitude of newly added features critical to MSI analyses. MSiReader is a free, open-source, and vendor-neutral software written in the MATLAB platform and is capable of analyzing most common MSI data formats. A standalone version of the software, which does not require a MATLAB license, is also distributed. The newly incorporated data analysis features expand the utility of MSiReader beyond simple visualization of molecular distributions. The MSiQuantification tool allows researchers to calculate absolute concentrations from quantification MSI experiments exclusively through MSiReader software, significantly reducing data analysis time. An image overlay feature allows the incorporation of complementary imaging modalities to be displayed with the MSI data. A polarity filter has also been incorporated into the data loading step, allowing the facile analysis of polarity switching experiments without the need for data parsing prior to loading the data file into MSiReader. A quality assurance feature to generate a mass measurement accuracy (MMA) heatmap for an analyte of interest has also been added to allow for the investigation of MMA across the imaging experiment. Most importantly, as new features have been added performance has not degraded, in fact it has been dramatically improved. These new tools and the improvements to the performance in MSiReader v1.0 enable the MSI community to evaluate their data in greater depth and in less time. Graphical Abstract ᅟ.}, number={1}, journal={Journal of The American Society for Mass Spectrometry}, publisher={Springer Science and Business Media LLC}, author={Bokhart, Mark T. and Nazari, Milad and Garrard, Kenneth P. and Muddiman, David C.}, year={2017}, month={Sep}, pages={8–16} }
 @article{furst_dow_garrard_sohn_fixsen_rinehart_mentzell_veach_rizzo_dhabal_2016, title={Design and validation of the mounting structure for BETTII balloon-based telescope with thin-walled optics}, volume={2}, ISSN={["2329-4221"]}, DOI={10.1117/1.jatis.2.2.024001}, abstractNote={Abstract. The NASA Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII) system is designed to study the infrared emissions from star formation and active galactic nuclei through a double-Fourier Michelson interferometer located on a balloon at an altitude of 37 km. The BETTII external optics include a pair of identical beam-reducing, four-mirror telescopes, each with a 522-mm aperture, nonrotationally symmetric primary mirror. These telescopes were designed and assembled at the North Carolina State University Precision Engineering Consortium and are composed entirely of thin-walled aluminum components. The mounting structure is designed to be light weight and stiff to reduce thermal equilibration time in the rarified air at the edge of space and to maintain robust alignment of the optical elements. The mounts also prevent deformation of the large optical elements via custom-built kinematic Kelvin couplings and fixed-load clamps; the maximum form error of the optical surfaces are 300 nm RMS. This work details the design of the thin mirrors and mounting structure as well as validation of the mount assembly process, mount stiffness, and the kinematic couplings.}, number={2}, journal={JOURNAL OF ASTRONOMICAL TELESCOPES INSTRUMENTS AND SYSTEMS}, author={Furst, Stephen and Dow, Tom and Garrard, Ken and Sohn, Alex and Fixsen, Dale and Rinehart, Stephen and Mentzell, Eric and Veach, Todd and Rizzo, Maxime and Dhabal, Arnab}, year={2016}, month={Apr} }
 @article{meier_garrard_muddiman_2014, title={Silver dopants for targeted and untargeted direct analysis of unsaturated lipids via infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI)}, volume={28}, ISSN={["1097-0231"]}, DOI={10.1002/rcm.7041}, abstractNote={RATIONALEUnsaturated lipids play a crucial role in cellular processes as signaling factors, membrane building blocks or energy storage molecules. However, adequate mass spectrometry imaging of this diverse group of molecules remains challenging. In this study we implemented silver cationization for direct analysis by infrared matrix‐assisted laser desorption electrospray ionization (IR‐MALDESI) to enhance the ion abundances for olefinic lipids and facilitate peak assignment.}, number={22}, journal={RAPID COMMUNICATIONS IN MASS SPECTROMETRY}, author={Meier, Florian and Garrard, Kenneth P. and Muddiman, David C.}, year={2014}, month={Nov}, pages={2461–2470} }
 @article{robichaud_garrard_barry_muddiman_2013, title={MSiReader: An Open-Source Interface to View and Analyze High Resolving Power MS Imaging Files on Matlab Platform}, volume={24}, ISSN={["1879-1123"]}, DOI={10.1007/s13361-013-0607-z}, abstractNote={During the past decade, the field of mass spectrometry imaging (MSI) has greatly evolved, to a point where it has now been fully integrated by most vendors as an optional or dedicated platform that can be purchased with their instruments. However, the technology is not mature and multiple research groups in both academia and industry are still very actively studying the fundamentals of imaging techniques, adapting the technology to new ionization sources, and developing new applications. As a result, there important varieties of data file formats used to store mass spectrometry imaging data and, concurrent to the development of MSi, collaborative efforts have been undertaken to introduce common imaging data file formats. However, few free software packages to read and analyze files of these different formats are readily available. We introduce here MSiReader, a free open source application to read and analyze high resolution MSI data from the most common MSi data formats. The application is built on the Matlab platform (Mathworks, Natick, MA, USA) and includes a large selection of data analysis tools and features. People who are unfamiliar with the Matlab language will have little difficult navigating the user-friendly interface, and users with Matlab programming experience can adapt and customize MSiReader for their own needs.}, number={5}, journal={JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY}, author={Robichaud, Guillaume and Garrard, Kenneth P. and Barry, Jeremy A. and Muddiman, David C.}, year={2013}, month={May}, pages={718–721} }
 @article{furst_dow_garrard_sohn_2010, title={Automated Part Centering With Impulse Actuation}, volume={132}, ISSN={["1528-8935"]}, DOI={10.1115/1.4000681}, abstractNote={Centering a part on a spindle for precision machining is a tedious, time-consuming task. Currently, a skilled operator must measure the run-out of a part using a displacement gauge, then tap the part into place using a plastic or rubber hammer. This paper describes a method to automatically center a part on a vacuum chuck with initial run-out as large as 2.5 mm. The method involves measuring the magnitude and direction of the radial run-out and then actuating the part until the part and spindle centerlines are within 5 μm of each other. The run-out can be measured with either a touch probe mounted to a machine axis or an electronic gauge. The part is tapped into place with a linear actuator driven by a voice coil motor. This paper includes an analysis of run-out measurement uncertainty as well as the design, performance modeling, and testing of the alignment actuator. This actuator was employed for part realignment and successfully positioned a hemispherical part with an initial run-out of 1–2.5 mm to within 5 μm of the spindle centerline. This capability shows that the run-out of a part manually placed on flat vacuum chuck can be automatically corrected.}, number={1}, journal={JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME}, author={Furst, S. J. and Dow, T. A. and Garrard, K. and Sohn, A.}, year={2010}, month={Feb} }
 @misc{sohn_garrard_dow_2005, title={Polar coordinate-based profilometer and methods}, volume={6,895,682}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Sohn, A. and Garrard, K. P. and Dow, T. A.}, year={2005} }
 @article{balkey_day_batha_elliot_pierce_sandoval_2004, title={Production and metrology of cylindrical inertial confinement fusion targets with sinusoidal perturbations}, volume={45}, ISSN={["1943-7641"]}, DOI={10.13182/FST04-A435}, abstractNote={Abstract Shock waves generated during inertial confinement fusion implosions propagate toward the center of the capsule encountering interfaces between materials with different densities, such as between the ablator and the DT fuel. These interactions are hydrodynamically unstable and the resulting instability causes mixing of the materials at the interface, which is predicted to have detrimental effects on fusion burn. In this experiment, the growth of a single-mode perturbation machined into a radiographically opaque marker layer, driven by a strong shock, is measured during a cylindrically symmetric implosion. These measurements are used to validate simulations and theories of the complex hydrodynamics. Since any perturbation on the marker layer surface will lead to instability growth, precise knowledge of the initial conditions is critical. The targets used in this experiment have up to a 3.0-μm-amplitude, mode 28 (θ = 98 μm) sinusoidal perturbation machined into a 438-μm-outerradius aluminum band with a nominal thickness of 8 μm. The perturbations were machined using a fast-tool servo [B. JARED and T. A. DOW, Precision Engineering Center Annual Report, North Carolina State University, Raleigh NC, p. 123 (1996)] and were metrologized using a linear variable differential transformer [FRANK J. OLIVER, Practical Instrumentation Tranducers, p. 42-45, Hayden Book Company (1971)]. In this paper, the importance of metrology is discussed and is shown to be critical to the interpretation of experimental results.}, number={2}, journal={FUSION SCIENCE AND TECHNOLOGY}, author={Balkey, MM and Day, RD and Batha, SH and Elliot, NE and Pierce, T and Sandoval, DL}, year={2004}, month={Mar}, pages={107–112} }
 @article{dow_miller_garrard_2004, title={Tool force and deflection compensation for small milling tools}, volume={28}, ISSN={["1873-2372"]}, DOI={10.1016/S0141-6359(03)00072-2}, abstractNote={A technique to compensate for deflection of small milling tools (diameter<1 mm) has been demonstrated. This open-loop technique involves predicting the cutting and thrust forces, applying these forces to the tool, calculating the shape error due to tool deflection and creating a new tool path to eliminate this error. The tool force model has evolved from a decade of research to predict the forces in diamond turning. This model was modified to include the effects of tool rotation in milling as well as the changes in contact area and force direction using a ball end mill to create a free form surface. Experimental measurements were made to corroborate the components of the tool forces in the cutting and thrust directions. The force model was then combined with tool stiffness to calculate the deflection of the tool as a function of the depth of cut, the up-feed per revolution and the geometry of the part. Two experiments were used to demonstrate the effectiveness of this error compensation technique—a slot and a large circular groove. Each experiment reduced the error due to tool deflection by an order of magnitude from 20–50 μm to 2–5 μm.}, number={1}, journal={PRECISION ENGINEERING-JOURNAL OF THE INTERNATIONAL SOCIETIES FOR PRECISION ENGINEERING AND NANOTECHNOLOGY}, author={Dow, TA and Miller, EL and Garrard, K}, year={2004}, month={Jan}, pages={31–45} }
 @article{jared_dow_garrard_moorefield_barnes_day_hatch_salzer_rivera_1997, title={Fabrication of hydrodynamic instability targets}, volume={31}, ISSN={["0748-1896"]}, DOI={10.13182/FST97-A30810}, number={4}, journal={FUSION TECHNOLOGY}, author={Jared, BH and Dow, TA and Garrard, KP and Moorefield, GM and Barnes, C and Day, RD and Hatch, DJ and Salzer, LJ and Rivera, G}, year={1997}, month={Jul}, pages={501–503} }