467 results on '"T. Case"'
Search Results
2. Potential effects of insects on survival of Monilinia vaccinii-corymbosi pseudosclerotia
- Author
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S.L. Annis and T. Case
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Horticulture - Published
- 2023
3. Interactions Between Intracellular Fungal Pathogens and Host Phagocytes
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Nicola T. Case, Nicole Robbins, and Leah E. Cowen
- Published
- 2023
4. Endothelin receptor antagonism improves glucose tolerance and adipose tissue inflammation in an experimental model of systemic lupus erythematosus
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Osvaldo Rivera-Gonzalez, Clinton T. Case, Natalie A. Wilson, Joshua S. Speed, and Erin B. Taylor
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Physiology ,Physiology (medical) ,Endocrinology, Diabetes and Metabolism - Abstract
Endothelin-1 (ET-1) is elevated in patients with systemic lupus erythematosus (SLE), an autoimmune disease characterized by high rates of hypertension, renal injury, and cardiovascular disease. SLE is also associated with increased prevalence of obesity and insulin resistance compared to the general population. In the present study, we tested the hypothesis that elevated ET-1 in SLE is contributes to obesity and insulin resistance. For these studies, we used the NZBWF1 mouse model of SLE, which develops obesity and insulin resistance on a normal chow diet. To test this hypothesis, we treated control (NZW) and SLE (NZBWF1) mice with vehicle, atrasentan (ET
- Published
- 2022
5. Long‐term Gut Microbiota Depletion Exacerbates Hypertension and Renal Injury in an Experimental Model of Autoimmune Disease
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Erin Taylor, Clinton T. Case, Jayla‐Danielle Reese, William Kalusche, and Katie Jones
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Genetics ,Molecular Biology ,Biochemistry ,Biotechnology - Published
- 2022
6. MW NDT An Inspection Method
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Shant Kenderian and Joseph T. Case
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Engineering ,business.industry ,Nondestructive testing ,Inspection method ,Mechanical engineering ,business - Published
- 2019
7. STRATIGRAPHIC, DEPOSITIONAL ENVIRONMENTAL AND PALEONTOLOGIC ANALYSIS OF THE HARRISBURG MEMBER OF THE KAIBAB FORMATION IN NORTH CENTRAL ARIZONA
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Zachery T. Case and R. LaRell Nielson
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Sedimentary depositional environment ,Paleontology ,North central ,Geology - Published
- 2020
8. Narrowband oblique whistler-mode waves: comparing properties observed by Parker Solar Probe at <0.3 AU and STEREO at 1 AU
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Stuart D. Bale, Justin C. Kasper, Aaron Breneman, Katherine Goodrich, Marc Pulupa, Milan Maksimovic, Keith Goetz, T. Case, Michael L. Stevens, T. Dudok de Wit, Davin Larson, B. Short, Jasper Halekas, Michel Moncuquet, David M. Malaspina, Robert J. MacDowall, Cynthia A Cattell, Peter Harvey, P. Whittesley, John W. Bonnell, University of Minnesota System, Department of Physics and Astronomy [Iowa City], University of Iowa [Iowa City], Space Sciences Laboratory [Berkeley] (SSL), University of California [Berkeley], University of California-University of California, Department of Climate and Space Sciences and Engineering (CLaSP), University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Smithsonian Astrophysical Observatory, Smithsonian Institution, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), University of California, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), GSFC Solar System Exploration Division, NASA Goddard Space Flight Center (GSFC), and University of Colorado [Boulder]
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010504 meteorology & atmospheric sciences ,Whistler ,Astrophysics ,Electron ,01 natural sciences ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,waves ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences ,Physics ,Scattering ,scattering ,Astronomy and Astrophysics ,plasmas ,Computational physics ,Solar wind ,Strahl ,Amplitude ,solar wind ,Heat flux ,instabilities ,13. Climate action ,Space and Planetary Science ,Beta (plasma physics) ,Physics::Space Physics ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] - Abstract
Aims.Large amplitude narrowband obliquely propagating whistler-mode waves at frequencies of ~0.2fce(electron cyclotron frequency) are commonly observed at 1 AU, and they are most consistent with the whistler heat flux fan instability. We want to determine whether similar whistler-mode waves occur inside 0.3 AU and how their properties compare to those at 1 AU.Methods.We utilized the waveform capture data from the Parker Solar Probe Fields instrument from Encounters 1 through 4 to develop a data base of narrowband whistler waves. The Solar Wind Electrons Alphas and Protons Investigation (SWEAP) instrument, in conjunction with the quasi-thermal noise measurement from Fields, provides the electron heat flux, beta, and other electron parameters.Results.Parker Solar Probe observations inside ~0.3 AU show that the waves are often more intermittent than at 1 AU, and they are interspersed with electrostatic whistler-Bernstein waves at higher-frequencies. This is likely due to the more variable solar wind observed closer to the Sun. The whistlers usually occur within regions when the magnetic field is more variable and often with small increases in the solar wind speed. The near-Sun whistler-mode waves are also narrowband and large amplitude, and they are associated with beta greater than 1. The association with heat flux and beta is generally consistent with the whistler fan instability. Strong scattering of strahl energy electrons is seen in association with the waves, providing evidence that the waves regulate the electron heat flux.
- Published
- 2021
9. UWB antipodal vivaldi antenna for microwave imaging of construction materials and structures
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Mahdi Moosazadeh, Sergey Kharkovsky, Joseph T. Case, and Bijan Samali
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020208 electrical & electronic engineering ,0202 electrical engineering, electronic engineering, information engineering ,020206 networking & telecommunications ,02 engineering and technology ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials - Published
- 2017
10. Analyzing structural changes in SNOMED CT’s Bacterial infectious diseases using a visual semantic delta
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James T. Case, Christopher Ochs, and Yehoshua Perl
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0301 basic medicine ,Computer science ,Software tool ,Health Informatics ,computer.software_genre ,Article ,Software release life cycle ,Terminology ,03 medical and health sciences ,0302 clinical medicine ,BACTERIAL INFECTIOUS DISEASES ,Humans ,030212 general & internal medicine ,SNOMED CT ,Information retrieval ,End user ,business.industry ,Systematized Nomenclature of Medicine ,Bacterial Infections ,Change analysis ,Semantics ,Computer Science Applications ,030104 developmental biology ,Artificial intelligence ,business ,computer ,Algorithms ,Software ,Natural language processing - Abstract
Display Omitted We introduce a semantic delta methodology for analyzing change in SNOMED CT.Two change analysis techniques are combined into one comprehensive methodology.Changes to sets of concepts are summarized and visualized.Changes in SNOMED CT's Bacterial infectious disease subhierarchy are analyzed. Thousands of changes are applied to SNOMED CTs concepts during each release cycle. These changes are the result of efforts to improve or expand the coverage of health domains in the terminology. Understanding which concepts changed, how they changed, and the overall impact of a set of changes is important for editors and end users. Each SNOMED CT release comes with delta files, which identify all of the individual additions and removals of concepts and relationships. These files typically contain tens of thousands of individual entries, overwhelming users. They also do not identify the editorial processes that were applied to individual concepts and they do not capture the overall impact of a set of changes on a subhierarchy of concepts.In this paper we introduce a methodology and accompanying software tool called a SNOMED CT Visual Semantic Delta (semantic delta for short) to enable a comprehensive review of changes in SNOMED CT. The semantic delta displays a graphical list of editing operations that provides semantics and context to the additions and removals in the delta files. However, there may still be thousands of editing operations applied to a set of concepts. To address this issue, a semantic delta includes a visual summary of changes that affected sets of structurally and semantically similar concepts. The software tool for creating semantic deltas offers views of various granularities, allowing a user to control how much change information they view. In this tool a user can select a set of structurally and semantically similar concepts and review the editing operations that affected their modeling. The semantic delta methodology is demonstrated on SNOMED CTs Bacterial infectious disease subhierarchy, which has undergone a significant remodeling effort over the last two years.
- Published
- 2017
11. Mining non-lattice subgraphs for detecting missing hierarchical relations and concepts in SNOMED CT
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Guo-Qiang Zhang, Wei Zhu, Shiqiang Tao, Olivier Bodenreider, Licong Cui, and James T. Case
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0301 basic medicine ,Quality Assurance, Health Care ,Health Informatics ,quality assurance ,Research and Applications ,SNOMED CT ,computer.software_genre ,Terminology ,03 medical and health sciences ,0302 clinical medicine ,Data Mining ,ontology ,030212 general & internal medicine ,Mathematics ,Subject Headings ,business.industry ,Systematized Nomenclature of Medicine ,Objective quality ,non-lattice subgraph ,030104 developmental biology ,Scalability ,Ontology ,Data mining ,Artificial intelligence ,business ,computer ,Natural language processing - Abstract
Objective: Quality assurance of large ontological systems such as SNOMED CT is an indispensable part of the terminology management lifecycle. We introduce a hybrid structural-lexical method for scalable and systematic discovery of missing hierarchical relations and concepts in SNOMED CT. Material and Methods: All non-lattice subgraphs (the structural part) in SNOMED CT are exhaustively extracted using a scalable MapReduce algorithm. Four lexical patterns (the lexical part) are identified among the extracted non-lattice subgraphs. Non-lattice subgraphs exhibiting such lexical patterns are often indicative of missing hierarchical relations or concepts. Each lexical pattern is associated with a potential specific type of error. Results: Applying the structural-lexical method to SNOMED CT (September 2015 US edition), we found 6801 non-lattice subgraphs that matched these lexical patterns, of which 2046 were amenable to visual inspection. We evaluated a random sample of 100 small subgraphs, of which 59 were reviewed in detail by domain experts. All the subgraphs reviewed contained errors confirmed by the experts. The most frequent type of error was missing is-a relations due to incomplete or inconsistent modeling of the concepts. Conclusions: Our hybrid structural-lexical method is innovative and proved effective not only in detecting errors in SNOMED CT, but also in suggesting remediation for these errors.
- Published
- 2017
12. Miniaturized UWB Antipodal Vivaldi Antenna and Its Application for Detection of Void Inside Concrete Specimens
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Mahdi Moosazadeh, Bijan Samali, Sergey Kharkovsky, and Joseph T. Case
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Patch antenna ,Materials science ,Coaxial antenna ,business.industry ,020208 electrical & electronic engineering ,Antenna aperture ,Antenna measurement ,020206 networking & telecommunications ,02 engineering and technology ,Antenna factor ,law.invention ,Antenna efficiency ,Optics ,law ,0202 electrical engineering, electronic engineering, information engineering ,Electrical and Electronic Engineering ,business ,Vivaldi antenna ,Monopole antenna - Abstract
A miniaturized antipodal Vivaldi antenna to operate from 1 to 30 GHz is designed for nondestructive testing and evaluation of construction materials, such as concrete, polymers, and dielectric composites. A step-by-step procedure has been employed to design and optimize performance of the proposed antenna. First, a conventional antipodal Vivaldi antenna (CAVA) is designed as a reference. Second, the CAVA is shortened to have a small size of the CAVA. Third, to extend the low end of frequency band, the inner edges of the top and bottom radiators of the shortened CAVA have been bent. To enhance gain at lower frequencies, regular slit edge technique is employed. Finally, a half elliptical-shaped dielectric lens as an extension of the antenna substrate is added to the antenna to feature high gain and front-to-back ratio. A prototype of the antenna is employed as a part of the microwave imaging system to detect voids inside concrete specimen. High-range resolution images of voids are achieved by applying synthetic aperture radar algorithm.
- Published
- 2017
13. Improved Radiation Characteristics of Small Antipodal Vivaldi Antenna for Microwave and Millimeter-Wave Imaging Applications
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Mahdi Moosazadeh, Joseph T. Case, Bijan Samali, and Sergey Kharkovsky
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Physics ,Coaxial antenna ,business.industry ,020208 electrical & electronic engineering ,Antenna measurement ,Antenna aperture ,Astrophysics::Instrumentation and Methods for Astrophysics ,020206 networking & telecommunications ,02 engineering and technology ,Antenna factor ,Radiation pattern ,law.invention ,Optics ,law ,0202 electrical engineering, electronic engineering, information engineering ,Electrical and Electronic Engineering ,Antenna gain ,business ,Vivaldi antenna ,Monopole antenna - Abstract
A small antipodal Vivaldi antenna with rectangular slits at sun-shaped configuration and a half elliptical-shaped dielectric lens is designed for microwave and millimeter-wave imaging applications. The slits are developed to extend low end of frequency band and increase antenna gain at lower frequencies, while the lens is applied to this antenna to feature high gain at higher frequencies, high front-to-back ratio, low sidelobe and cross-polarization levels, narrow half-power beamwidth, and modification on E-plane tilt of beam. A prototype of the antenna with small size of 30 × 55 × 0.508 mm3 is fabricated and employed as a part of microwave and millimeter-wave imaging system. Applicability of the proposed antenna for 3-D and 2-D images of targets such as rubber discs and metal rods at different depths inside construction materials including foam and plasterboard sheet-layered structures is demonstrated. High-range resolution images are achieved by applying synthetic aperture radar algorithm.
- Published
- 2017
14. Early Inhibition of Angiotensin Converting Enzyme Abolishes the Androgen‐Mediated Blood Pressure Increase in a Model of PCOS
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Damian G. Romero, Savannah Marie Stockton, Licy L. Yanes Cardozo, Ruth M. Vinson, Huimin Zhang, Yvonne P. Zuchowski, Alessandro Subauste, Edgar D. Torres Fernandez, and Clinton T. Case
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medicine.medical_specialty ,biology ,medicine.drug_class ,Chemistry ,Angiotensin-converting enzyme ,Androgen ,Biochemistry ,Endocrinology ,Internal medicine ,Genetics ,medicine ,biology.protein ,Blood pressure increase ,Molecular Biology ,Biotechnology - Published
- 2019
15. Overlapping Complex Concepts Have More Commission Errors, Especially in Intensive Terminology Auditing
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Ling, Zheng, Hao, Liu, Yehoshua, Perl, James, Geller, Christopher, Ochs, and James T, Case
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Subject Headings ,Systematized Nomenclature of Medicine ,Longitudinal Studies ,Articles ,Classification ,Medical Records ,Software - Abstract
SNOMED CT is a large, complex and widely-used terminology. Auditing is part of the life cycle of terminologies. A review of terminologies’ content can identify two error categories: commission errors, such as an incorrect parent or attribute relationship, indicating errors in a concept’s modeling, and omission errors, such as missing a parent or attribute relationship, representing incomplete modeling of a concept. According to our experience, terminology curators are mostly interested in commission errors. In recent years, a long-term remodeling project has addressed modeling issues in SNOMED CT’s Infectious disease and Congenital disease subhierarchies. In this longitudinal study, we investigated a posteriori the efficacy of complex concepts, called overlapping concepts, to identify commission errors during intensive auditing periods and during maintenance periods over several releases. The algorithmic implication is that when auditing resources are scarce, a methodology of auditing first, or only, the overlapping concepts will obtain a higher auditing yield.
- Published
- 2019
16. Skeletal Kinship Analysis Using Developmental Anomalies of the Foot
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L. B. Jones, A. M. Offenbecker, and D. T. Case
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Orthodontics ,030222 orthopedics ,Archeology ,medicine.medical_specialty ,060101 anthropology ,business.industry ,06 humanities and the arts ,Surgery ,Os Trigonum ,03 medical and health sciences ,0302 clinical medicine ,Anthropology ,medicine ,Kinship ,0601 history and archaeology ,business ,Calcaneonavicular coalition ,Talocalcaneal coalition ,Foot (unit) - Published
- 2016
17. Microwave and millimetre wave antipodal Vivaldi antenna with trapezoid‐shaped dielectric lens for imaging of construction materials
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Joseph T. Case, Sergey Kharkovsky, and Mahdi Moosazadeh
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Materials science ,business.industry ,020208 electrical & electronic engineering ,Antipodal point ,020206 networking & telecommunications ,02 engineering and technology ,Directivity ,law.invention ,Beamwidth ,Optics ,Microwave imaging ,law ,0202 electrical engineering, electronic engineering, information engineering ,Reference antenna ,Electrical and Electronic Engineering ,Antenna (radio) ,business ,Vivaldi antenna ,Microwave - Abstract
High-quality microwave and millimetre wave imaging of construction materials and structures requires ultra-wideband (UWB) techniques to provide high-range resolution as well as a reasonable penetration depth. A modified compact microwave and millimetre wave UWB antipodal Vivaldi antenna is designed and presented in this study. First, the conventional antipodal Vivaldi antenna is designed as a reference antenna. Then, to provide the desired frequency range (3.4-40 GHz) with increased gain at its lower frequencies, the slit edge technique is applied, thus creating a periodic slit edge antipodal Vivaldi antenna (PSEAVA). Finally, a trapezoid-shaped dielectric lens (TDL) as an extension of the substrate is added and optimised to increase gain and directivity at higher frequencies of the frequency range, creating PSEAVA with a TDL (PSEAVA-TDL). The results show that the PSEAVA-TDL has the highest gain (up to 16 dB) and front-to-back ratio (up to 37.5 dB), and the narrowest half power beamwidth (down to 11.7°). A prototype of the proposed PSEAVA-TDL with compact size of 40 × 90 × 0.508 mm 3 is fabricated and applied for the imaging of samples made of construction materials. High-range resolution images of the samples are obtained with this antenna by using synthetic aperture radar algorithm.
- Published
- 2016
18. Health Consequences of European Contact in the Great Plains: A Comparison of Systemic Stress Levels in Pre- and Post-Contact Arikara Populations
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D. T. Case and A. M. Offenbecker
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Archeology ,education.field_of_study ,060101 anthropology ,060102 archaeology ,Health consequences ,Population ,06 humanities and the arts ,Enamel hypoplasia ,medicine.disease ,Geography ,Systemic stress ,Anthropology ,Bioarchaeology ,medicine ,0601 history and archaeology ,education ,Paleopathology ,Pre and post ,Demography ,Porotic hyperostosis - Abstract
The biocultural effects of European contact varied considerably throughout the Americas. Some populations were decimated by colonialism, while others benefited from trade relationships and access to new technologies. It has been suggested that initial contact with European fur traders and explorers was economically favourable for Plains village populations, thereby facilitating a period of cultural florescence. In this study, we evaluate the hypothesis that Plains groups were better off than their predecessors during the initial contact period by comparing frequencies of enamel hypoplasia, cribra orbitalia, and porotic hyperostosis in pre- and post-contact Arikara skeletal assemblages. We included both juveniles and adults in our sample to capture variation in the stress experience of different segments of the population. Our analysis revealed similarly low frequencies of cribra orbitalia in the pre- and post-contact groups and no observed cases of porotic hyperostosis. Enamel hypoplasia, however, was significantly more prevalent among post-contact Arikara villagers when compared to their pre-contact counterparts, which suggests that stress levels were higher after European contact. Additionally, enamel hypoplasia was most common among post-contact juveniles. The elevated frequency of enamel hypoplasia in the post-contact sample combined with the low frequencies of cribra orbitalia and porotic hyperostosis suggests that disease stress, rather than nutritional deficiencies, was likely responsible for the decline in overall health following European contact. These results also suggest that juveniles are sensitive indicators of systemic stress within a population and should be included in bioarchaeological analyses of prehistoric health when available. Copyright © 2015 John Wiley & Sons, Ltd.
- Published
- 2015
19. Antipodal Vivaldi antenna with improved radiation characteristics for civil engineering applications
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Mahdi Moosazadeh, Joseph T. Case, Bijan Samali, and Sergey Kharkovsky
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Engineering ,Void (astronomy) ,business.industry ,Frequency band ,020208 electrical & electronic engineering ,Impedance bandwidth ,Bent molecular geometry ,Antipodal point ,020206 networking & telecommunications ,02 engineering and technology ,Radiation ,Civil engineering ,law.invention ,Microwave imaging ,law ,0202 electrical engineering, electronic engineering, information engineering ,Electrical and Electronic Engineering ,business ,Vivaldi antenna ,Networking & Telecommunications - Abstract
An ultra-wideband elliptically tapered antipodal Vivaldi antenna designed for civil engineering applications is presented. It is based on design of a conventional antipodal Vivaldi antenna (CAVA) which impedance bandwidth is limited at low end of frequency band. To extend impedance bandwidth, inner edges of top and bottom radiators of the CAVA have been properly bent; however, its gain and front-to-back (F-to-B) ratio is low at the low frequencies. To enhance gain and F-to-B ratio, the comb-shaped slits on edges of the radiators of CAVA are applied. The obtained results exhibit the impedance bandwidth of 1.65-18 GHz, gain of 6.7 dB at 1.65 GHz, and F-to-B ratio of 42 dB at 13.5 GHz that are higher than those parameters of the CAVA. Applicability of the proposed antenna for detection of void inside concrete beam is demonstrated. First, models of the proposed antenna and concrete beam possessing void are created in computer simulation technology and numerical study is performed. Then, a prototype of the antenna is fabricated and employed as part of microwave imaging system to verify simulation results and to detect voids inside concrete beam.
- Published
- 2017
20. Activation of Neural Cell Fate Programs Toward Direct Conversion of Adult Human Fibroblasts into Tri-Potent Neural Progenitors Using OCT-4
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Ryan R. Mitchell, Aline Fiebig-Comyn, Deda C. Gillespie, Mickie Bhatia, Jong-Hee Lee, Yannick D. Benoit, Rami Mechael, Daniel T. Case, Javier Alamilla, and Eva Szabo
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Adult ,Cellular differentiation ,Action Potentials ,Mice, SCID ,Biology ,Oct-4 ,Article ,Neural Stem Cells ,Mice, Inbred NOD ,Neurosphere ,Animals ,Humans ,Progenitor cell ,Neural cell ,Cells, Cultured ,Progenitor ,SOXB1 Transcription Factors ,Teratoma ,Cell Differentiation ,Cell Biology ,Hematology ,Fibroblasts ,Neural stem cell ,Cell biology ,Immunology ,Octamer Transcription Factor-3 ,Reprogramming ,Stem Cell Transplantation ,Developmental Biology - Abstract
Several transcription factors and methods have been used to convert fibroblasts directly to neural fate and have provided insights into molecular mechanisms as to how each of these required factors orchestrate neural fate conversion. Here, we provide evidence and detailed characterization of the direct conversion process of primary adult human fibroblasts (hFib) to neural progenitor cells (NPC) using OCT4 alone. Factors previously associated with neural cell fate conversion were induced during hFib-NPC(OCT-4) generation, where OCT-4 alone was sufficient to induce neural fate conversion without the use of promiscuous small-molecule manipulation. Human Fib-NPC(OCT-4) proliferate, express neural stem/progenitor markers, and possess developmental potential that gives rise to all three major subtypes of neural cells: astrocytes, oligodendrocytes, and neurons with functional capacity. We propose a de-convoluted reprogramming approach for neural fate conversion in which OCT4 is sufficient for inducing neural conversion from hFib for disease modeling as well as the fundamental study of early neural fate induction.
- Published
- 2014
21. Modified Waveguide Flange for Evaluation of Stratified Composites
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Matthew Kempin, Reza Zoughi, Mohammad Tayeb Ghasr, and Joseph T. Case
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Materials science ,business.industry ,Dielectric ,Flange ,Physics::Classical Physics ,Waveguide (optics) ,Waveguide flange ,Nondestructive testing ,Electrical and Electronic Engineering ,Reflection coefficient ,Composite material ,business ,Material properties ,Instrumentation ,Ground plane - Abstract
Nondestructive evaluation of stratified (layered) composite structures at microwave and millimeter-wave frequencies is of great interest in many applications where simultaneous determination of the complex dielectric properties and thicknesses of multiple layers is desired. Open-ended rectangular waveguide probes, radiating into such structures, are effective tools for this purpose. The technique utilizes a full-wave electromagnetic model that accurately models the complex reflection coefficient as a function of frequency and material properties. While the electromagnetic model assumes an infinite waveguide flange (or ground plane), the measurements are conducted using a finite-sized flange. Consequently, the results of the electromagnetic model and those from measurements may not be sufficiently alike for accurate dielectric property and thickness evaluation. This paper investigates the effect of using an open-ended waveguide with a standard finite-sized flange on the error in evaluating the complex dielectric properties of a composite structure. Additionally, we present the design of a novel flange that markedly reduces this undesired effect by producing very similar electric field properties, at the flange aperture, to those created by an infinite flange. Finally, the efficacy of the design for evaluating the dielectric properties of a layered composite structure is demonstrated as well.
- Published
- 2014
22. Correcting Mutual Coupling and Poor Isolation for Real-Time 2-D Microwave Imaging Systems
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Reza Zoughi, Joseph T. Case, and Mohammad Tayeb Ghasr
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Synthetic aperture radar ,Coupling ,Engineering ,business.industry ,Signal ,Microwave imaging ,Electronic engineering ,Preprocessor ,Electrical and Electronic Engineering ,business ,Instrumentation ,Image resolution ,Image restoration ,Microwave - Abstract
Recent technological advancements have made it possible to produce synthetic aperture radar (SAR) based microwave images in real time by using a variety of microwave imaging (array) systems. However, depending on the imaging array construction and the data collection scheme, the pertinent data of interest may be corrupted by undesired signals resulting from array element mutual coupling and overall poor isolation. Poor isolation associated with array elements may result from imperfect RF switching, internal coupling mechanisms inherent in a measurement system, or imperfect signal tagging schemes (i.e., multiple elements modulating when using the modulated scatterer technique). Images produced from such corrupted data are blurred or have artifacts that tend to mask the desired indications. This paper demonstrates the extension of a well-known correlation canceling technique for the purpose of preprocessing the data to remove such undesired coupling effects. To demonstrate its effectiveness, it is applied to a recently developed 2-D high-resolution and real-time microwave imaging system (camera). This camera is composed of 576 array elements, which are susceptible to the type of signal degradation mentioned above. Three correction estimates of the preprocessor are performed and compared. Two of the correction estimates directly address coupling, and the third, which does not consider coupling, is used for comparison purposes. Simulation results show the efficacy of this method, which is then corroborated by experiments.
- Published
- 2014
23. Layer- and cell type-selective co-transmission by a basal forebrain cholinergic projection to the olfactory bulb
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Nathaniel N. Urban, Rebecca P. Seal, Sean Paul G. Williams, Daniel T. Case, Jeremy Y. Gedeon, and Shawn D. Burton
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0301 basic medicine ,Olfactory system ,Male ,Amino Acid Transport Systems, Acidic ,Science ,General Physics and Astronomy ,Mice, Transgenic ,Optogenetics ,Biology ,Inhibitory postsynaptic potential ,Diagonal Band of Broca ,Synaptic Transmission ,General Biochemistry, Genetics and Molecular Biology ,Article ,03 medical and health sciences ,0302 clinical medicine ,Prosencephalon ,Animals ,Cholinergic neuron ,lcsh:Science ,gamma-Aminobutyric Acid ,Basal forebrain ,Multidisciplinary ,Olfactory tubercle ,General Chemistry ,Anatomy ,Olfactory Bulb ,Cholinergic Neurons ,Olfactory bulb ,Mice, Inbred C57BL ,030104 developmental biology ,nervous system ,Cholinergic ,lcsh:Q ,Female ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Cholinergic neurons in the basal forebrain project heavily to the main olfactory bulb, the first processing station in the olfactory pathway. The projections innervate multiple layers of the main olfactory bulb and strongly influence odor discrimination, detection, and learning. The precise underlying circuitry of this cholinergic input to the main olfactory bulb remains unclear, however. Here, we identify a specific basal forebrain cholinergic projection that innervates select neurons concentrated in the internal plexiform layer of the main olfactory bulb. Optogenetic activation of this projection elicits monosynaptic nicotinic and GABAergic currents in glomerular layer-projecting interneurons. Additionally, we show that the projection co-expresses markers for GABAergic neurotransmission. The data thus implicate neurotransmitter co-transmission in the basal forebrain regulation of this inhibitory olfactory microcircuit., Cholinergic neurons innervate multiple layers in the main olfactory bulb but the precise circuitry of this input is not known. Here the authors show that VGLUT3+ cholinergic neurons selectively innervate deep short axon cells in specific layers and elicit robust monosynaptic GABAergic and nicotinic postsynaptic currents.
- Published
- 2016
24. Compressed sensing for SAR‐based wideband three‐dimensional microwave imaging system using non‐uniform fast Fourier transform
- Author
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Yahong Rosa Zheng, Zengli Yang, Hamed Kajbaf, and Joseph T. Case
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Synthetic aperture radar ,Engineering ,Image quality ,business.industry ,Truncation error (numerical integration) ,Fast Fourier transform ,Iterative reconstruction ,Microwave imaging ,Compressed sensing ,Radar imaging ,Electrical and Electronic Engineering ,business ,Algorithm ,Remote sensing - Abstract
A new compressed sensing (CS) image reconstruction method is proposed for high-resolution wideband threedimensional synthetic aperture radar (SAR) imaging systems. In contrast to existing CS SAR methods that employ only a forward SAR transform in pre- or post-processing, the proposed method employs both forward SAR and reverse SAR (R-SAR) transforms in each CS iteration to improve the quality of reconstructed images. This study proposes a simple and elegant truncation repair method to combat the truncation error and utilises non-uniform fast Fourier transform to reduce the SAR and R-SAR transform errors, thereby ensuring the convergence of the CS algorithm and improving the quality of the reconstructed images. The proposed CS SAR method is applied to microwave and millimeter wave imaging systems for non-destructive evaluation of materials embedded in stratified media. Three different specimens under test are measured by conventional uniform sampling and by random under-sampling with 20% or 30% spatial points of the uniform sampling. The reconstructed images show that, albeit having much less measurement points, the proposed CS method achieves better image quality and lower background artefacts than the images reconstructed from the fullysampled uniform measurements.
- Published
- 2013
25. Nonuniform Manual Scanning for Rapid Microwave Nondestructive Evaluation Imaging
- Author
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Joseph T. Case, Mohammad Tayeb Ghasr, and Reza Zoughi
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Synthetic aperture radar ,Engineering ,business.industry ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Process (computing) ,Background noise ,Nondestructive testing ,Computer vision ,Artificial intelligence ,Electrical and Electronic Engineering ,Wideband ,business ,Raster scan ,Instrumentation ,Spatial analysis ,Microwave - Abstract
Wideband synthetic aperture radar (SAR) technique is a robust imaging tool for microwave and millimeter-wave imaging such as nondestructive evaluation applications. In this paper, we present an alternative method to conventional raster scanning involving manually selected and nonuniformly distributed measurement positions, enabling the production of complete SAR images—potentially using only a fraction of the conventionally required measured data. The user is kept informed throughout the scanning process by a stream of real-time SAR images. Finally, data reconstruction algorithms are used offline to produce high-quality images with considerably lower background noise and image artifacts as compared to the real-time images. We also introduce a novel reconstruction method that uses the components of the SAR algorithm to advantageously exploit the inherent spatial information contained in the data, resulting in a superior data reconstruction and final SAR image. This paper presents the measurement methodology along with the images obtained from three different specimens of increasing geometrical complexity.
- Published
- 2013
26. Optimum 2-D Nonuniform Spatial Sampling for Microwave SAR-Based NDE Imaging Systems
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Reza Zoughi, Mohammad Tayeb Ghasr, and Joseph T. Case
- Subjects
Synthetic aperture radar ,Engineering ,business.industry ,Signal reconstruction ,Nonuniform sampling ,Sampling (statistics) ,Iterative reconstruction ,Microwave imaging ,Radar imaging ,Nyquist–Shannon sampling theorem ,Electrical and Electronic Engineering ,business ,Instrumentation ,Remote sensing - Abstract
Microwave and millimeter-wave synthetic aperture radar (SAR)-based imaging techniques, which are used for nondestructive evaluation (NDE), have shown tremendous usefulness for the inspection of a wide variety of complex composite materials and structures. An important practical issue associated with these imaging techniques is the required criteria associated with the physical gathering of the imaging data. In previous work on uniform sampling optimization, it was shown that the (uniform) spatial sampling density should be higher than the Nyquist density if preservation of spatial resolution, as defined by the half-power width of an ideal point target, is of interest. Conversely, nonuniform sampling has shown to provide effective signal reconstruction even for average spatial sampling densities below the Nyquist density-a distinct advantage over uniform sampling. This paper presents a comprehensive study into the optimization of nonuniform sampling for microwave SAR-based NDE imaging using three typical reconstruction techniques for nonuniformly sampled data, including natural interpolation, area-weighted Fourier integration, and conjugate gradient residual error minimization methods. To study the efficacy of these reconstruction methods, simulations of a point target were performed for a range of target distances and a range of average spatial sample separations. Resulting SAR images from the reconstruction techniques are then analyzed and compared according to two metrics: error between an image and an ideal image and resolution as determined by the half-power width of a point target. This is followed by experimental results corroborating the simulation results. Finally, nonuniform sampling requirements, given a minimum metric performance, are generalized for a given imager aperture size.
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- 2012
27. Fatal musculoskeletal injuries of Quarter Horse racehorses: 314 cases (1990–2007)
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Tiffany L. Sarrafian, Francisco A. Uzal, Deryck H. Read, Susan M. Stover, Janet Moore, James T. Case, B. M. Daft, and Hailu Kinde
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Horse racing ,medicine.medical_specialty ,General Veterinary ,biology ,business.industry ,Incidence (epidemiology) ,General surgery ,biology.animal_breed ,Anatomic region ,Surgery ,Fatal injury ,Fractures, Bone ,Quarter horse ,Forelimb ,medicine ,Animals ,Wounds and Injuries ,Horse Diseases ,Horses ,Joint Diseases ,Anatomic Location ,business ,Retrospective Studies ,Sports - Abstract
Objective—To determine major causes of death and the anatomic location of musculoskeletal injuries in Quarter Horse racehorses in California. Design—Retrospective case series. Animals—314 Quarter Horse racehorses with musculoskeletal injuries that were necropsied through the California Horse Racing Board Postmortem Program from 1990 to 2007. Procedures—Postmortem pathology reports were retrospectively reviewed. Musculoskeletal injuries were categorized by anatomic region and described. The number of Quarter Horse starts and starters for the same period of time were obtained from a commercial database for determination of fatal injury incidence. Results—Musculoskeletal injuries accounted for 314 of the 443 (71 %) Quarter Horse racehorses that died during the 18-year study period. Fatal musculoskeletal injuries occurred at a rate of 2.0 deaths/1,000 race starts and 18.6 deaths/1,000 horses that started a race. Musculoskeletal injuries occurred predominantly during racing (84%) and in the forelimbs (81%). The most common fatal musculoskeletal injuries were metacarpophalangeal and metatarsophalangeal joint (fetlock) support injuries (40%) and carpal (24%), vertebral (10%), and scapular (8%) fractures. Proximal interphalangeal (pastern) joint luxations resulted in death of 3% of horses. Fracture configurations of some bones were consistent with those of Thoroughbred racehorses. Evidence of preexisting stress remodeling of bone was reported for some fractures. Conclusions and Clinical Relevance—Knowledge of common locations and types of fatal musculoskeletal injuries in racing Quarter Horses may enhance practitioners' ability to detect mild injuries early, rest horses, and help prevent catastrophic injuries.
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- 2012
28. Bond quality inspection for nonhomogeneous highly attenuating heat shield blocks
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Shant Kenderian, Yong Kim, and Joseph T. Case
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Engineering ,Optics ,Shearography ,business.industry ,Nondestructive testing ,Temporal resolution ,Thermography ,Heat shield ,Ultrasonic sensor ,Computed radiography ,business ,Signal - Abstract
A NASA effort is underway to develop a nondestructive inspection method to evaluate the bonding condition for heat shield blocks that are bonded to a composite substrate. The initial effort is reported in this paper. The goal is to demonstrate a proof of concept for a reliable detection method using a single-sided scan capability applied from the outside of the heat shield blocks. Two representative samples with known defects are made available for the initial proof of concept; the results of one sample are reported here. The two specimens had been scanned using various nondestructive testing methods including immersion ultrasound, handheld ultrasound, air-coupled ultrasound, microwave, Terahertz, computed radiography, and shearography. These efforts were performed by industry experts and academia. All were limited in their detectability of the known flawed regions in the specimens and suffered high levels of uncertainty in the good regions. Most nondestructive evaluation methods are sensitive to detecting changes in the material property. This means that an air pocket is easy to detect in an unbounded interface but when the air pocket is absent and the two surfaces are in intimate contact (kissing bond) most methods fails to detect the difference. Electromagnetic methods (radiography, thermography, microwave, Terahertz) will not detect a change in material property. Shearography is not successful in attempting to detect changes in stiffness through the highly damping thick heat shield layer. As a mechanical wave, ultrasound is the primary method that may be able to detect a kissing bond. However, it was quickly recognized that ultrasound has to overcome a number of difficult challenges related to the nonhomogeneous and highly damping nature of the thermal shield material. Inhomogeneity causes pronounced changes in signal strength that make the distinction between good and bad areas very difficult. At the same time, scatter and attenuation become detrimental to high frequency ultrasonic signals, which are necessary to resolve echoes returning from the bond line. Conversely, low frequency sound waves provide poor spatial and temporal resolution due to the broader wavelengths associated with the signal.
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- 2016
29. Auditing complex concepts of SNOMED using a refined hierarchical abstraction network
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Duo Wei, James T. Case, Kent A. Spackman, Michael Halper, Gai Elhanan, Yue Wang, Yan Chen, Yehoshua Perl, George Hripcsak, Huanying Gu, and Junchuan Xu
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Theoretical computer science ,020205 medical informatics ,Computer science ,Group auditing ,Poison control ,SNOMED ,Complex concept ,Health Informatics ,02 engineering and technology ,Disjoint sets ,computer.software_genre ,Article ,Terminology ,03 medical and health sciences ,Systematized Nomenclature of Medicine ,Terminology as Topic ,Taxonomy (general) ,0202 electrical engineering, electronic engineering, information engineering ,030304 developmental biology ,Abstraction (linguistics) ,Taxonomy ,0303 health sciences ,Hierarchy ,SNOMED CT ,Auditing ,Models, Theoretical ,Quality assurance ,Computer Science Applications ,Abstraction network ,Neighborhood auditing ,Data mining ,computer ,Partitioning - Abstract
Auditors of a large terminology, such as SNOMED CT, face a daunting challenge. To aid them in their efforts, it is essential to devise techniques that can automatically identify concepts warranting special attention. “Complex” concepts, which by their very nature are more difficult to model, fall neatly into this category. A special kind of grouping, called a partial-area, is utilized in the characterization of complex concepts. In particular, the complex concepts that are the focus of this work are those appearing in intersections of multiple partial-areas and are thus referred to as overlapping concepts. In a companion paper, an automatic methodology for identifying and partitioning the entire collection of overlapping concepts into disjoint, singly-rooted groups, that are more manageable to work with and comprehend, has been presented. The partitioning methodology formed the foundation for the development of an abstraction network for the overlapping concepts called a disjoint partial-area taxonomy. This new disjoint partial-area taxonomy offers a collection of semantically uniform partial-areas and is exploited herein as the basis for a novel auditing methodology. The review of the overlapping concepts is done in a top-down order within semantically uniform groups. These groups are themselves reviewed in a top-down order, which proceeds from the less complex to the more complex overlapping concepts. The results of applying the methodology to SNOMED’s Specimen hierarchy are presented. Hypotheses regarding error ratios for overlapping concepts and between different kinds of overlapping concepts are formulated. Two phases of auditing the Specimen hierarchy for two releases of SNOMED are reported on. With the use of the double bootstrap and Fisher’s exact test (two-tailed), the auditing of concepts and especially roots of overlapping partial-areas is shown to yield a statistically significant higher proportion of errors.
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- 2012
- Full Text
- View/download PDF
30. Loss of VGLUT3 Produces Circadian-Dependent Hyperdopaminergia and Ameliorates Motor Dysfunction and l-Dopa-Mediated Dyskinesias in a Model of Parkinson's Disease
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Christopher B. Divito, Robert H. Edwards, Daniel T. Case, Maria E. Rubio, Jennifer A. Stancati, Kathy Steece-Collier, David Sulzer, Hui Zhang, Sean Paul G. Williams, Lianteng Zhi, Rebecca P. Seal, Timothy J. Collier, and Caryl E. Sortwell
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Nervous system ,Male ,medicine.medical_specialty ,Dyskinesia, Drug-Induced ,Parkinson's disease ,Mice, 129 Strain ,Amino Acid Transport Systems, Acidic ,Dopamine ,Mice, Transgenic ,Striatum ,Biology ,Levodopa ,Mice ,Parkinsonian Disorders ,Internal medicine ,Basal ganglia ,medicine ,Animals ,Mice, Knockout ,General Neuroscience ,Dopaminergic ,Glutamate receptor ,Articles ,medicine.disease ,Circadian Rhythm ,Mice, Inbred C57BL ,Motor Skills Disorders ,Disease Models, Animal ,medicine.anatomical_structure ,Endocrinology ,Female ,Neuron ,Neuroscience ,medicine.drug - Abstract
The striatum is essential for many aspects of mammalian behavior, including motivation and movement, and is dysfunctional in motor disorders such as Parkinson's disease. The vesicular glutamate transporter 3 (VGLUT3) is expressed by striatal cholinergic interneurons (CINs) and is thus well positioned to regulate dopamine (DA) signaling and locomotor activity, a canonical measure of basal ganglia output. We now report that VGLUT3 knock-out (KO) mice show circadian-dependent hyperlocomotor activity that is restricted to the waking cycle and is due to an increase in striatal DA synthesis, packaging, and release. Using a conditional VGLUT3 KO mouse, we show that deletion of the transporter from CINs, surprisingly, does not alter evoked DA release in the dorsal striatum or baseline locomotor activity. The mice do, however, display changes in rearing behavior and sensorimotor gating. Elevation of DA release in the global KO raised the possibility that motor deficits in a Parkinson's disease model would be reduced. Remarkably, after a partial 6-hydroxydopamine (6-OHDA)-mediated DA depletion (∼70% in dorsal striatum), KO mice, in contrast to WT mice, showed normal motor behavior across the entire circadian cycle.l-3,4-dihydroxyphenylalanine-mediated dyskinesias were also significantly attenuated. These findings thus point to new mechanisms to regulate basal ganglia function and potentially treat Parkinson's disease and related disorders.SIGNIFICANCE STATEMENTDopaminergic signaling is critical for both motor and cognitive functions in the mammalian nervous system. Impairments, such as those found in Parkinson's disease patients, can lead to severe motor deficits. Vesicular glutamate transporter 3 (VGLUT3) loads glutamate into secretory vesicles for neurotransmission and is expressed by discrete neuron populations throughout the nervous system. Here, we report that the absence of VGLUT3 in mice leads to an upregulation of the midbrain dopamine system. Remarkably, in a Parkinson's disease model, the mice show normal motor behavior. They also show fewer abnormal motor behaviors (dyskinesias) in response tol-3,4-dihydroxyphenylalanine, the principal treatment for Parkinson's disease. The work thus suggests new avenues for the development of novel treatment strategies for Parkinson's disease and potentially other basal-ganglia-related disorders.
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- 2015
31. Optimum Two-Dimensional Uniform Spatial Sampling for Microwave SAR-Based NDE Imaging Systems
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Mohammad Tayeb Ghasr, Reza Zoughi, and Joseph T. Case
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Synthetic aperture radar ,Engineering ,Aperture ,Image quality ,business.industry ,Acoustics ,Sampling (statistics) ,Microwave imaging ,Radar imaging ,Electrical and Electronic Engineering ,Raster scan ,business ,Instrumentation ,Image resolution ,Remote sensing - Abstract
Microwave imaging systems for nondestructive evaluation, based on 3-D synthetic aperture radar (SAR) techniques, utilize either a real aperture, composed of many antennas mounted next to one another, or a synthetic aperture, generated by raster scanning a single antenna. To obtain a quality SAR image, the spatial sampling must be dense enough to accurately sample the electric field reflected from a target. Conversely, the quantity of spatial samples may be optimally reduced, resulting in reduced system complexity and required resources for systems employing real apertures and reduced imaging time for synthetic aperture systems. In the literature, it has been reported that the optimum sampling step size is equal to the theoretical resolution, as per the Nyquist rate. It has also been reported that an image generated using a sampling step size equal to the theoretical resolution may not possess the same spatial resolution as predicted. Also, as expected and reported, resolution is dependent upon the distance between the target and the aperture, aperture dimensions, and antenna beamwidth. However, existing formulations of SAR resolution do not account for all of the physical characteristics of a measurement (e.g., 2-D limited-size aperture, electric field decreasing with distance from the measuring antenna, etc.). This paper presents a theoretical formulation of resolution and a study into optimum uniform spatial sampling by analyzing simulated 3-D SAR images according to metrics representing image quality, namely, half-power resolution and RMS error between practically sampled images and an ideally sampled image. The results of this simulation demonstrate optimum sampling given design requirements that fully explain resolution dependence on sampling step size. Also, it is found that there is additional widening of the 2-D spectral estimation of the data due to the aperture-limited nature of the measurements, which further influences the choice of sampling step size. Subsequently, the simulated results are compared to experimental results corroborating the efficacy of the formulation. Finally, design curves and procedures are proposed for selecting sampling step size as per resolution requirements.
- Published
- 2011
32. Pre- and postsynaptic properties of glutamatergic transmission in the immature inhibitory MNTB-LSO pathway
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Daniel T. Case and Deda C. Gillespie
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Auditory Pathways ,Patch-Clamp Techniques ,Physiology ,Glycine ,Action Potentials ,Glutamic Acid ,AMPA receptor ,Olivary Nucleus ,Neurotransmission ,Biology ,Receptors, Presynaptic ,Inhibitory postsynaptic potential ,Receptors, N-Methyl-D-Aspartate ,Rats, Sprague-Dawley ,Glutamatergic ,Pons ,Vesicular Glutamate Transport Proteins ,Animals ,Trapezoid body ,Receptors, AMPA ,Sound Localization ,gamma-Aminobutyric Acid ,Neuronal Plasticity ,General Neuroscience ,Age Factors ,Glutamate receptor ,Neural Inhibition ,Synaptic Potentials ,Rats ,Animals, Newborn ,Excitatory postsynaptic potential ,NMDA receptor ,Neuroscience - Abstract
The lateral superior olive (LSO) integrates excitatory inputs driven by sound arriving at the ipsilateral ear with inhibitory inputs driven by sound arriving at the contralateral ear in order to compute interaural intensity differences needed for localizing high-frequency sound sources. Specific mechanisms necessary for developmental refinement of the inhibitory projection, which arises from the medial nucleus of the trapezoid body (MNTB), have only been partially deciphered. The demonstration that immature MNTB-LSO synapses release glutamate has led to a model in which early glutamate neurotransmission plays a major role in inhibitory plasticity. We used whole cell electrophysiology in acute auditory brain stem slices of neonatal rats to examine glutamatergic transmission in the developing MNTB-LSO pathway. Unexpectedly, AMPA receptor (AMPAR)-mediated responses were prevalent at the earliest ages. We found a salient developmental profile for NMDA receptor (NMDAR) activation, described both by the proportion of total glutamate current and by current durations, and we found evidence for distinct release probabilities for GABA/glycine and glutamate in the MNTB-LSO pathway. The developmental profile of NMDAR is consistent with the possibility that the inhibitory MNTB-LSO pathway experiences a sensitive period, driven by cochlear activity and mediated by GluN2B-containing NMDARs, between postnatal days 3 and 9. Differing neurotransmitter release probabilities could allow the synapse to switch between GABA/glycinergic transmission and mixed glutamate/GABA/glycinergic transmission in response to changing patterns of spiking activity.
- Published
- 2011
33. Characteristics of Thoroughbred and Quarter Horse racehorses that sustained a complete scapular fracture
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Susan M. Stover, Janet Moore, Rick M. Arthur, Rachel Entwistle, James T. Case, Hailu Kinde, S. A. Vallance, Mark L Anderson, and B. C. Barr
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musculoskeletal diseases ,medicine.medical_specialty ,education.field_of_study ,biology ,Right scapula ,business.industry ,Incidence (epidemiology) ,biology.animal_breed ,Population ,General Medicine ,musculoskeletal system ,medicine.disease ,Surgery ,Scapular fracture ,Catastrophic injury ,Right forelimb ,Quarter horse ,medicine ,Physical therapy ,business ,education - Abstract
Summary Reasons for performing study: To determine if scapular fractures occur in racehorses with distinctive characteristics. Objectives: To test the hypothesis that Thoroughbred (TB) and Quarter Horse (QH) racehorses with a scapular fracture have similar characteristics that are different from those of their respective racetrack populations. Methods: Necropsy findings, case details, last race information and career earnings for TB and QH racehorses that had a scapular fracture in California between 1990 and 2008 were retrospectively compared between breeds. Horse signalment, career earnings, career starts and race characteristics were obtained for all California racehorses. Comparisons were made between affected horses, other racehorses that died, and all horses that raced, in California during the 19 year period. Results: Seventy-three TB and 28 QH racehorses had a similar, complete comminuted scapular fracture with an articular component, and right forelimb predilection. The QHs had a higher incidence of scapular fracture incurred during racing than TBs (0.98 vs. 0.39/1000 starters). The TB and QH incident rates for musculoskeletal deaths incurred racing were 20.5 and 17.5/1000 starters, respectively; however, a greater proportion of TB musculoskeletal deaths occurred training (40% vs. 8%). Horses with a scapular fracture were more likely to be male and aged 2 or ≥5 years than the racetrack population. Most affected QHs (64%) were 2-year-olds; most TBs (74%) were aged ≥3 years. Scapular fractures occurred more commonly during racing in QHs (70%) than TBs (44%). Race-related scapular fracture was more likely to occur in a Maiden race than in a non-Maiden race. Horses with a scapular fracture had fewer career starts than the racetrack population. Conclusions and potential relevance: Despite breed differences for signalment and exercise distances, both breeds incur a complete scapular fracture that is more likely to occur in the right scapula of young and older, male racehorses, early in their race career or after few races. Quarter Horses sustain a catastrophic scapular fracture more frequently than TBs.
- Published
- 2011
34. The application of GIS and spatiotemporal analyses to investigations of unusual marine mammal strandings and mortality events
- Author
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Stephanie A. Norman, Sandra Dubpernell, Deborah A. Duffield, Dyanna M. Lambourn, James M. Rice, Matt Klope, Jessie Huggins, James T. Case, Susan Berta, Tim E. Carpenter, M. Bradley Hanson, Joseph K. Gaydos, and John Calambokidis
- Subjects
Fishery ,Geography ,Marine mammal ,Work (electrical) ,Aquatic Science ,Ecology, Evolution, Behavior and Systematics - Abstract
This is the publisher’s final pdf. The published article is copyrighted by John Wiley & Sons, Inc. and can be found at: http://onlinelibrary.wiley.com/journal/10.1111/%28ISSN%291748-7692. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work.
- Published
- 2011
35. Assessment of the Quality of Multi-Institutional Data for Population-Based Epidemiological Studies: A Case Study of Atoxoplasmosis in Bali Mynahs (Leucopsar rothschildi)
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James T. Case, Michael H. Ziccardi, Lisa B. Done, and Jonna A. K. Mazet
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medicine.medical_specialty ,Data consistency ,Medical Records Systems, Computerized ,media_common.quotation_subject ,Population ,Problem list ,Eimeriida ,Consistency (statistics) ,Statistics ,Epidemiology ,Medical Records, Problem-Oriented ,medicine ,Animals ,Quality (business) ,education ,Leucopsar rothschildi ,media_common ,education.field_of_study ,General Veterinary ,biology ,Bird Diseases ,Coccidiosis ,General Medicine ,biology.organism_classification ,Geography ,Data quality ,Starlings ,Animals, Zoo ,Animal Science and Zoology - Abstract
To evaluate the potential to conduct population-based epidemiologic studies using multi-institutional data, the quality of data extracted from the MedARKS system was evaluated with regard to atoxoplasmosis in Bali mynahs (Leucopsar rothschildi). Data extracted for 338 Bali mynahs from 34 institutions were analyzed for completeness, correctness, and consistency and subjectively analyzed for accessibility. Data completeness was ascertained by analysis of missing records, tests, and blank fields. Two hundred and sixty four records had animal enclosure information missing, nine records were missing from the parasitology module, and 85 records did not include tests or results. Data correctness was assessed by evaluation of unclear and inaccurate results. From 2,432 parasitology records, 81 tests (3.3%) were not definitive because of uninterpretable entries. Data consistency was assessed by comparing the problem list to positive tests in the parasitology module and listing of buffy coat smears in the clinical pathology module. Overall, six different terms with 28 values were used to denote "positive for Atoxoplasma sp.," and a substantial number of discrepancies were found between problem lists, parasitology modules, and test findings among these data records. In general, this study showed that the data contained in a computer patient record (CPR) system for zoos has great promise for population-level studies if specific areas are addressed, including 1) reduced reliance on free-text data entry, 2) universal use of a standardized vocabulary, 3) use of methods to identify and track individual animals accurately and easily, 4) integration of data checks and maintenance methods, and 5) concerted use of "centralized" animal medical record information.
- Published
- 2011
36. High precision study of muon catalyzed fusion in D2 and HD gas
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G. N. Schapkin, S. M. Kozlov, N. I. Voropaev, V.A. Ganzha, A.A. Vasiliev, M. P. Faifman, T. Case, G. G. Semenchuk, Johann Marton, D. V. Balin, M. A. Soroka, B. Lauss, G. E. Petrov, F. J. Hartmann, V. Trofimov, An.A. Vorobyov, Kenneth M. Crowe, B. Gartner, C. Petitjean, Johann Zmeskal, E. M. Maev, and P. Kammel
- Subjects
Nuclear physics ,Nuclear reaction ,Physics ,Nuclear and High Energy Physics ,Muon-catalyzed fusion ,Muon ,Branching fraction ,Helium-3 ,Atomic physics ,Quantum number ,Hyperfine structure ,Lepton - Abstract
Muon catalyzed dd fusion in D2 and HD gases in the temperature range from 28 to 350 K was investigated in a series of experiments based on a time-projection ionization chamber operating with pure hydrogen. All main observables in this reaction chain were measured with high absolute precision including the resonant and non-resonant ddμ formation rates, the rate for hyperfine transitions in dμ atoms, the branching ratio of the two charge symmetric fusion channels 3He + n and t + p and the muon sticking probability. The report presents the final analysis of the data together with a comprehensive comparison with calculations based on recent μCF theories. The energy of the loosely bound ddμ state with quantum numbers J = 1, ν = 1, which is central to the mechanism of resonant molecule formation, is extracted with precision ɛ11(fit) = −1.9651(7) eV. in impressive agreement with the latest theoretical results ɛ11(theory) = −1.9646 eV.
- Published
- 2011
37. Rapid Rotary Scanner and Portable Coherent Wideband Q-Band Transceiver for High-Resolution Millimeter-Wave Imaging Applications
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F. de Paulis, Joseph T. Case, A Aflaki-Beni, A McClanahan, Reza Zoughi, Mohammad Tayeb Ghasr, K. Guinn, Sergey Kharkovsky, Mohamed A. Abou-Khousa, and David Pommerenke
- Subjects
Scanner ,Engineering ,transceiver ,business.industry ,Bandwidth (signal processing) ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,nondestructive testing (NDT) ,millimeter wave ,Servomotor ,Imaging ,spray-on foam insulation (SOFI) ,Nondestructive testing ,Extremely high frequency ,IQ receiver ,rotary scanner ,Electronic engineering ,Electrical and Electronic Engineering ,Wideband ,Transceiver ,business ,Raster scan ,Instrumentation - Abstract
Millimeter-wave imaging techniques, based on synthetic aperture focusing (SAF), have been successfully used for nondestructive testing (NDT) of various composite and aerospace structures. Most current imaging mechanisms utilize raster scanning platforms, whereby the imaging system is scanned in a rectangular grid over the structure-under-test (SUT). Most raster scanning platforms, although relatively simple in design and construction, are inherently slow. Furthermore, SAF techniques necessitates the use of vector-measuring instruments such as a vector network analyzer (VNA), which are typically: 1) bulky; 2) cannot be mounted on scanning platforms; 3) are not suitable for in-field use; and 4) expensive. These factors limit the effectiveness of these millimeter-wave imaging techniques in applications where frequent and rapid inspection of large structures is required. Hence, there is a great demand for rapid mechanical scanning systems combined with portable wideband transceivers in order to increase the utility of these imaging techniques, and provide a real solution to many practical NDT applications. To this end, a unique rotary scanner system, capable of scanning a relatively large area in a relatively short span of time, was designed and constructed. In addition, a custom-designed portable transceiver system operating in the frequency range of 35-45 GHz (Q-band) was developed and incorporated into the rotary scanner system for producing coherent (amplitude and phase) and accurate data suitable for synthetic aperture imaging and the 10-GHz bandwidth allows the generation of relatively high-resolution millimeter-wave holographical images. This paper presents the design of the rotary scanning system, the associated Q-band transceiver and the integration of the two systems via a custom-designed software. To illustrate the efficacy of the complete imaging system, SAF of several complex structures produced using the proposed system, are presented and discussed.
- Published
- 2011
38. Heterodyne Multifrequency Receiver for MST
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Reza Zoughi, Joseph T. Case, and Mohammad Tayeb Ghasr
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Heterodyne ,Synthetic aperture radar ,Image formation ,Computer science ,business.industry ,Superheterodyne receiver ,law.invention ,Reduction (complexity) ,Microwave imaging ,Optics ,Modulation ,law ,Radar imaging ,Nondestructive testing ,Electrical and Electronic Engineering ,business ,Instrumentation - Abstract
Recently, a real-time and portable 2-D microwave imaging system operating at 24 GHz, incorporating modulation schemes similar to modulated scatterer technique and synthetic aperture radar (SAR) imaging technique, was designed using a heterodyne receiver with superior performance compared with a homodyne receiver. Multifrequency SAR images have the added advantage of providing for: 1) coherent averaging of image data over frequency and hence increasing system signal-to-noise ratio (SNR) and 2) enable volumetric (3-D) image production. This letter describes modifications to this receiver for enabling multifrequency operation through phase uncertainty (PU) analysis. These modifications show significant reduction in PU, thereby allowing the coherent addition of data necessary for SAR image formation with higher overall SNR.
- Published
- 2014
39. Identification of tarsal coalition and frequency estimates from skeletal samples
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D. T. Case and Scott E. Burnett
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Archeology ,Joint disease ,Geography ,Smithsonian institution ,Anthropology ,medicine ,Calcaneus ,Tarsal coalition ,medicine.disease ,Calcaneonavicular coalition ,Genealogy - Abstract
Tarsal coalition is a congenital defect that results when adjacent tarsals fail to separate properly during embryonic development. Anatomically, coalitions present as non-osseous bridges of cartilage or fibrocar- tilage - and occasionally as osseous bridges - between two neighboring bones. In skeletons, non-osseous tarsal coalitions are recognizable as matching lesions between two bones at predictable locations. These coalitions are of interest because they are known to be heritable and are therefore useful for tracing genetic relatives in archaeological cemeteries, because they can be misinterpreted in skeletons as trauma or joint disease, and because they can result in associated pathology. However, despite a considerable literature on tarsal coalition, estimates of coalition frequencies disagree considerably, perhaps due to biases inherent in clinical sampling. In order to gain a better estimate of tarsal coalition frequencies in human populations, data were gathered on 342 European-Americans from the Terry Collection (Smithsonian Institution), 536 South Africans from the Dart Collection (University of Witwatersrand, South Africa), and 756 medieval Danish skeletons (Anthropological Database, Odense University). The Danish skeletons are archaeological, with sample sizes by coalition type ranging from 366-507 individuals. Examples of eight different types of intertarsal coalition were identified among the 1634 skeletons examined. Overall frequency estimates for tarsal coalition ranged from 2.1%-3.5%. South Africans exhibited significantly higher frequencies in the midfoot, with naviculocuneiform I coalition (1.0%) the most common type. Conversely, no coalitions of the midfoot were found among the Euro-Americans or medieval Danes. Instead, these groups exhibited calcaneonavicular coalition as the most common type in the hindfoot (2.0% and 2.1% respectively), while calcaneonavicular coalition was among the least common in the South Africans (0.2%). Copyright 2010 John Wiley & Sons, Ltd.
- Published
- 2010
40. Microencapsulated Herbicide-Treated Bark Mulches for Nursery Container Weed Control
- Author
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Luke T. Case and Hannah M. Mathers
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0106 biological sciences ,Alachlor ,04 agricultural and veterinary sciences ,Plant Science ,Pesticide ,Weed control ,01 natural sciences ,010602 entomology ,chemistry.chemical_compound ,Horticulture ,chemistry ,Agronomy ,visual_art ,Shoot ,040103 agronomy & agriculture ,visual_art.visual_art_medium ,0401 agriculture, forestry, and fisheries ,Bark ,Phytotoxicity ,Acetochlor ,Agronomy and Crop Science ,Mulch ,Mathematics - Abstract
Nursery container preemergence herbicides must be applied multiple times, usually every 6 to 8 wk, in order to maintain acceptable weed control. Nursery growers have identified extended duration of container preemergence activity as a research priority for reduction of herbicide usage and costs. The objective of this study was to determine if the combination of slow-release (microencapsulated [ME]) formulations of alachlor and acetochlor with wood-based organic mulches could provide extended efficacy and reduced phytotoxicity vs. over-the-top (OTT) sprays or mulch alone. Efficacy and phytotoxicity studies were conducted over 3 yr with various plants. Both acetochlor formulation OTT sprays reduced spirea shoot dry weights at 45 and 110 days after treatment (DAT) compared with the controls, and emulsifiable concentrate (EC) acetochlor OTT spray also reduced shoot dry weights of rose. No herbicide-treated bark mulch (TBM) combination reduced rose or spirea shoot dry weights. EC acetochlor + hardwood (in 2003) was the only treatment to provide 100% weed control at 45 and 110 DAT. The addition of EC or ME acetochlor to mulch reduced phytotoxicity and extended efficacy in 2002 and 2003; alachlor EC or ME TBM did not. Regardless of bark type, 3-yr average EC and ME TBM were 80% more effective than untreated bark mulch (UBM) and 83% and 98% more effective at 45 and 110 DAT, respectively than their comparable OTT sprays. Of the eight treatments that received ratings above commercially acceptable, averaged over dates and years, the three providing the least phytotoxicity and greatest extent, consistency, and duration of efficacy were all TBM combinations: EC acetochlor + Douglas fir or hardwood bark, EC acetochlor + pine, and ME acetochlor + pine. TBM-reduced phytotoxicity compared with OTT sprays.
- Published
- 2010
41. GROWTH ACCELERATION AND INCREASED OUT PLANT SURVIVAL OF ONTARIO AND OHIO GROWN TREE LINERS
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S. E. Svenson, R. Zondag, D. Rivera, Hannah M. Mathers, Daniel K. Struve, and Luke T. Case
- Subjects
Horticulture ,Cold resistance ,Environmental science ,Greenhouse ,Sowing ,Growing season ,Christian ministry ,Forestry ,High stress ,Production system - Abstract
A production system developed at Ohio State University (OSU), Columbus, OH, using retractable roof greenhouses (RRGs) (Cravo Equipment, Ltd., Brantford, ON, Canada) and containerized tree liner production has indicated acceleration of production times when out planted to Pot-in-Pot (PIP) or nursery fields versus conventional bareroot (BR) or polyhouse production. The system also increased cropping consistency via reduced mortalities and showed promise in new market expansion, including higher priced, difficult-to-grow species. In 2004, #3 (trade 3-gallon or 11.4 L) containerized tree liners from RRGs had 0% mortality versus field BR production Quercus rubra at 42% after out-planting into nursery fields to grow on as specimen trees. Averaged over species, RRG liners reached saleable size of 50 mm caliper two years sooner than the BR liners (a 40% reduction in production time). In 2006, #3 containerized tree liners from RRG's had 27% mortality versus field BR production at 87% after out-planting to #7 (trade 7-gallon or 26.5 L) containers and harsh conditions in PIP fields. Averaged over species and one growing season, caliper and height of RRG liners were 82 and 84% larger than BR liners, respectively. Recently RRG liners have shown utility in high stress environments along Ontario, Canada highways leading The Ontario Ministry of Transportation to research an optimized planting process including use of RRG's liners.
- Published
- 2010
42. Sudden death in racing Thoroughbred horses: An international multicentre study of post mortem findings
- Author
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Tim D H Parkin, Francisco A. Uzal, K. Lam, H. Aida, J. D. Pack, N Horadagoda, Brian D. Stewart, Lisa Boden, Bruce C. McGorum, J. T. Charles, C. H. Lyle, K. Kusano, Ian A. Gardner, Ron Slocombe, Karen J. Blissitt, and James T. Case
- Subjects
medicine.medical_specialty ,business.industry ,Blood Vessel Rupture ,General Medicine ,medicine.disease ,Sudden death ,Surgery ,Multicenter study ,Internal medicine ,Hemorrhagic complication ,Medicine ,Pulmonary failure ,business ,Spinal cord injury ,Acute collapse ,Cause of death - Abstract
Summary Reasons for performing study: To improve the understanding of exercise related sudden death in Thoroughbred racehorses. Objectives: To describe the post mortem findings in cases of sudden death associated with exercise in 268 Thoroughbred racehorses. Methods: Gross and histological post mortem findings of 268 cases of sudden death were collated and reviewed. Cases originated from 6 racing jurisdictions around the world. Sudden death was defined as acute collapse and death in a closely observed and previously apparently healthy Thoroughbred racehorse, during, or within one hour after, exercise. Cause of death as determined by the attending pathologist was categorised as definitive, presumptive or unexplained and compared between the different populations. Cardiopulmonary lesions recorded at post mortem examination were compared between different populations. Results: Pathologists recorded a definitive cause of death in 53% (143/268) of cases. Major definitive causes of sudden death included cardiac failure, apparent pulmonary failure, pulmonary haemorrhage, haemorrhage associated with pelvic fractures or with idiopathic blood vessel rupture, and spinal cord injury. A presumptive cause of death was made in 25% (67/268) of cases and death remained unexplained in 22% (58/268) of cases. There were several statistically significant inter-population differences in the cause of death and in reporting of cardiopulmonary lesions. Conclusions: Sudden death can be attributed to a variety of causes. Causes of sudden death and the lesions found in cases of exercise-related sudden death are similar in different racing jurisdictions. However, the lesions are often not specific for the cause of death and determination of the cause of death is therefore affected by interpretation by the individual pathologist.
- Published
- 2010
43. Accessory navicular: A heritable accessory bone of the human foot
- Author
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A. M. Offenbecker and D. T. Case
- Subjects
Archeology ,Ossification ,Frequency data ,Anatomy ,Biology ,Bridge (graph theory) ,Accessory navicular ,Anthropology ,Ossicle ,medicine ,Supernumerary ,medicine.symptom ,Skeletal material ,Foot (unit) - Abstract
The accessory navicular is a supernumerary bone of the human foot located medial to the navicular tuberosity and represents a secondary center of ossification that has failed to fuse to the main body of the navicular. Three forms of the accessory bone have been identified: Type I is an independent ossicle that is often embedded within the tibialis posterior tendon; Type II is a triangular accessory bone that attaches to the navicular tuberosity by means of a cartilaginous or fibrocartilaginous bridge; and Type III represents a fused Type II, which forms a hook-like protuberance extending from the tuberosity. The Type II accessory navicular is the most common of the three forms and is the most readily identifiable in skeletal material since it causes the navicular tuberosity to become abnormally flattened and porous. The purpose of this study was to describe the various manifestations of the accessory navicular in dry bone, to present and compare frequency data for several skeletal populations, and to consider questions of laterality and sex bias in trait expression. In total, the skeletons of 497 Danes, 460 Euro-Americans, 300 African Americans, 100 Japanese, and 205 Europeans were examined for the presence of the Type II accessory navicular. Overall frequencies for the five groups ranged from 2% in the African American sample to 5% in the Japanese sample. Since several family pedigrees have documented the accessory navicular as being an inherited skeletal defect, the relatively low frequency found in the present study makes this trait a potentially useful indicator of genetic relatedness within archaeological cemeteries. In addition, the trait was found to occur more often unilaterally than bilaterally and there was nearly equal incidence among males and females. Copyright © 2010 John Wiley & Sons, Ltd.
- Published
- 2010
44. A Case of Myelogenous Leukemia in the Cat
- Author
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Marvin T. Case
- Subjects
Gynecology ,Myelogenous ,medicine.medical_specialty ,Leukemia ,business.industry ,Medicine ,business ,medicine.disease ,Surgery - Abstract
Summary Myelogenous leukemia was diagnosed in a 4-year old female cat. The onset of clinical illness was sudden, and clinical signs present were weakness, splenomegaly, lymphadenopathy, and pale mucous membranes. Hematologic examination revealed anemia, leukocytosis and many immature granulocytes in the peripheral blood. Splenomegaly, hepatomegaly, lymphadenopathy and increased amount of red bone marrow were the principal lesions seen post mortem. Microscopic examination of tissue sections revealed masses of tumor cells in the liver, spleen, lymph nodes, bone marrow, kidney and adrenal. The true myelogenous origin of the tumor cells was determined by peroxidase staining of blood, bone marrow and tissue impression smears. Zusammenfassung Ein Fall von myelonischer Leukose bei der Katze Bei einer 4jahrigen Katze wurde eine myeloische Leukose diagnostiziert. Die Krankheit setzte plotzlich ein. Klinisch wurden folgende Symptome festgestellt: Allgemeine Schwache, Splenomegalie, Lymphadenopathie, blasse Schleimhaute. Hamatologie: Anamie, Leukozytose, viele unreife Granulozyten im peripheren Blut. Sektionsbefund: Splenomegalie, Hepatomegalie, Lymphadenopathie, Vermehrung des roten Knochenmarkes. Histologie: Tumorzellen in Leber, Milz, Lymphknoten, Knochenmark, Niere und Nebenniere. Der myeloische Ursprung der Tumorzellen wurde durch die Peroxydase-Reaktion der Zellen aus dem Blut, dem Knochenmark und andern Geweben erhartet. Resume Un cas de leucemie myelogene chez le chat On diagnostique une leucemie myelogene chez un chat femelle âge de 4 ans. Les signes cliniques de la maladie se sont declares brusquement, avec des symptomes de faiblesse, splenomegalie, lymphadenopathie et muqueuses pâles. L'examen hematologique revele une anemie, une leucocytose et de nombreux granulocytes immatures dans le sang peripherique. Les principales lesion observees post mortem sont une splenomegalie, hepatomegalie, lymphadenopathie et une quantite accrue de moelle osseuse rouge. Un examen microscopique des coupes de tissus revele une multitude de cellules tumorales dans le foie, le rate, les ganglions lymphatiques, la moelle osseuse, les reins et les surrenales. On determine l'origine myelogene reelle des ces cellules tumorales par une coloration peroxydasique du sang et de la moelle osseuse et par des decalques de tissus. Resumen Un caso de leucemia mielogena en el gato En una gata, de 4 anos de edad, se diagnostico leucemia mielogena. La aparicion de la enfermedad clinica fue repentina, y los sintomas clinicos presentes eran adelgazamiento, esplenomegalia, linfadenopatia y membranas mucosas palidas. El examen hematologico revelo anemia, leucocitosis y muchos granulocitos inmaduros en la sangre periferica. Las lesiones principales observadas en la autopsia fueron: esplenomegalia, hepatomegalia, linfadenopatia y aumento de la cantidad de medula osea roja. El examen microscopico de cortes histologicos evidencio masas de celulas tumorales en el higado, bazo, ganglios linfaticos, medula osea, rinon y glandula anterrenal. El origen mielogeno verdadero de las celulas tumorales se confirmo mediante la coloracion peroxidasica de la sangre, medula osea y extensiones de impresion histica.
- Published
- 2010
45. Disulfide bonds in a recombinant protein modeled after a core repeat in an aquatic insect's silk protein
- Author
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Stanley V. Smith, John J. Correia, and Steven T. Case
- Subjects
Protein Denaturation ,Protein Folding ,animal structures ,Molecular Sequence Data ,Silk ,Biochemistry ,Chironomidae ,Mass Spectrometry ,Dithiothreitol ,chemistry.chemical_compound ,Tandem repeat ,Genes, Synthetic ,Animals ,Trypsin ,Amino Acid Sequence ,Cysteine ,Disulfides ,Sulfhydryl Compounds ,Amino Acids ,Protein disulfide-isomerase ,Molecular Biology ,Peptide sequence ,Repetitive Sequences, Nucleic Acid ,chemistry.chemical_classification ,Base Sequence ,Chemistry ,Proteins ,Recombinant Proteins ,Amino acid ,Sedimentation equilibrium ,Insect Proteins ,Protein folding ,Peptides ,Sequence Analysis ,Ultracentrifugation ,Research Article - Abstract
We constructed a gene encoding rCAS, recombinant constant and subrepeat protein, modeled after tandem repeats found in the major silk proteins synthesized by aquatic larvae of the midge, Chironomus tentans. Bacterially synthesized rCAS was purified to near homogeneity and characterized by several biochemical and biophysical methods including amino-terminal sequencing, amino acid compositional analysis, sedimentation equilibrium ultracentrifugation, and mass spectrometry. Complementing these techniques with quantitative sulfhydryl assays, we discovered that the four cysteines present in rCAS form two intramolecular disulfide bonds. Mapping studies revealed that the disulfide bonds are heterogeneous. When reduced and denatured rCAS was allowed to refold and its disulfide bonding state monitored, it again adopted a conformation with two intramolecular disulfide bonds. The inherent ability of rCAS to quantitatively form two intramolecular disulfide bonds may reflect a previously unknown feature of the in vivo silk proteins from which it is derived.
- Published
- 2008
46. Automatic Collection of Process Data to Support Air Force Dynamic Targeting Instructors
- Author
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F. T. Case, J. J. Ockerman, N. T. Koterba, O. A. Garcia, and B. A. Huguenin
- Subjects
Medical Terminology ,Weapon system ,Engineering ,Subject-matter expert ,Operations research ,business.industry ,Process (engineering) ,Automatic identification and data capture ,Systems engineering ,Space operations ,business ,Medical Assisting and Transcription - Abstract
The Air and space Operations Center (AOC), also deployed as Joint (JAOC) or Combined (CAOC), is the United States Air Force's (USAF's) weapon system for planning and executing theater-wide air and space forces. Like any USAF weapon system, trainers and warfighters need to assess AOC performance on a continual basis. Currently, no automated methods or tools exist to assess this performance. To address this need, a prototype assessment capability, the CAOC Performance Assessment System (CPAS) was developed. Working with and observing subject matter experts allowed engineers to identify the information required to support dynamic targeting training and assessment. Using rapid-prototyping spiral development, a “non-intrusive” data capture (collection and archiving) capability and an informative user display were developed and demonstrated. Specifically, CPAS collects AOC process data, correlates AOC data sources, and displays events and decisions that occur within the dynamic targeting cell of the AOC to support post-mission assessment of AOC process performance. It has been in use by the Air Force for over two years.
- Published
- 2008
47. On the volatility and production mechanisms of newly formed nitrate and water soluble organic aerosol in Mexico City
- Author
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A. T. Case Hanks, Arsineh Hecobian, Amy P. Sullivan, O. Vargas, Christos Fountoukis, Barry Lefer, Rodney J. Weber, Armistead G. Russell, Richard E. Peltier, Athanasios Nenes, Christopher J. Hennigan, and L. G. Huey
- Subjects
Hydrology ,Total organic carbon ,Troposphere ,Atmospheric Science ,chemistry.chemical_compound ,Volatilisation ,Nitrate ,chemistry ,Environmental chemistry ,Ammonium nitrate ,Particulates ,Dilution ,Aerosol - Abstract
Measurements of atmospheric gases and fine particle chemistry were made in the Mexico City Metropolitan Area (MCMA) at a site ~30 km down wind of the city center. Ammonium nitrate (NH4NO3) dominated the inorganic aerosol fraction and showed a distinct diurnal signature characterized by rapid morning production and a rapid mid-day concentration decrease. Between the hours of 08:00–12:45, particulate water-soluble organic carbon (WSOC) concentrations increased and decreased in a manner consistent with that of NO3−, and the two were highly correlated (R2=0.88) during this time. A box model was used to analyze these behaviors and showed that, for both NO3− and WSOC, the concentration increase was caused primarily (~75–85%) by secondary formation, with a smaller contribution (~15–25%) from the entrainment of air from the free troposphere. For NO3−, a majority (~60%) of the midday concentration decrease was caused by dilution from boundary layer expansion, though a significant fraction (~40%) of the NO3− loss was due to particle evaporation. The WSOC concentration decrease was due largely to dilution (~75%), but volatilization did have a meaningful impact (~25%) on the decrease, as well. The results provide an estimate of ambient SOA evaporation losses and suggest that a significant fraction (~35%) of the fresh MCMA secondary organic aerosol (SOA) measured at the surface volatilized.
- Published
- 2008
48. Abiotic Factors Influencing Root Growth of Woody Nursery Plants in Containers
- Author
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Daniel K. Struve, S.B. Lowe, Luke T. Case, Carolyn F. Scagel, and Hannah M. Mathers
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Abiotic component ,Moisture ,media_common.quotation_subject ,fungi ,Longevity ,food and beverages ,Sowing ,Root system ,Horticulture ,Biology ,Substrate (marine biology) ,Agronomy ,Transplanting ,Aeration ,media_common - Abstract
Container production has many advantages over traditional in-ground (field) production, including less damage occurring to the root system when transplanted, better establishment after transplanting, decreased labor and land acquisition costs for production, and increased product availability and longevity in the retail market. Growing plants in containers, however, alters root growth and function and can change root morphology. Numerous factors influence root growth in containers. Roots of container-grown plants are subjected to temperature and moisture extremes not normally found in field production. The effects of substrate aeration (Ea) as well as water holding capacity (Pv) interact with different pot characteristics, resulting in changes to root morphology. Successful plant establishment after transplanting is often linked to root health. This review focuses on the roles of substrate physical and chemical properties, container characteristics, and temperature in altering root growth in container-grown woody nursery crops. Root circling, planting too deeply or “too-deep syndrome” (TDS), and the use of composts as container substrates will also be examined.
- Published
- 2007
49. Rice Hulls, Leaf-waste Pellets, and Pine Bark as Herbicide Carriers for Container-grown Woody Ornamentals
- Author
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Jayesh B. Samtani, Luke T. Case, Hannah M. Mathers, and Gary J. Kling
- Subjects
biology ,Pellets ,Horticulture ,Oryzalin ,Rice hulls ,biology.organism_classification ,chemistry.chemical_compound ,chemistry ,visual_art ,Botany ,Ornamental plant ,visual_art.visual_art_medium ,Spiraea japonica ,Thuja occidentalis ,Spiraea nipponica ,Bark - Abstract
An integrated approach to weed control in nursery containers is crucial if herbicide applications during the growing season are to be reduced. This experiment, conducted in 2002 and 2003 in Urbana, Ill., evaluated rice hulls, leaf-waste pellets, and pine bark as herbicide carriers for the preemergence herbicides oryzalin at 2 lb/acre a.i. and diuron at 1 lb/acre a.i. The efficacy of the treatments in controlling annual weeds and the phytotoxic effects of the treatments on the woody plant species were evaluated in separate completely randomized designs. For the efficacy experiment, no ornamental plants were present and containers were each seeded with a mixture of 1:1:1 (by volume) of annual bluegrass (Poa annua), common groundsel (Senecio vulgaris), and shepherd's purse (Capsella bursa-pastoris) immediately after treatment applications. For the phytotoxicity experiment, ‘Goldflame’ spirea (Spiraea japonica), ‘Hetz Midget’ american arborvitae (Thuja occidentalis), and ‘Snowmound’ nippon spirea (Spiraea nipponica) were evaluated. No weed seeds were sown in the phytotoxicity containers. Treatments for both experiments included spray applications of herbicides with water or with one of the organic mulches as a carrier or one of the mulches alone. Evaluations were done 45 and 120 days after treatment (DAT) in both years. The organic carriers with herbicide sprays gave efficacy visual ratings equivalent to water as a carrier for both herbicides. Phytotoxicity was not observed in the spirea species in either year. For ‘Hetz Midget’ american arborvitae in 2002, diuron with water had the highest visual phytotoxicity rating. Diuron phytotoxicity on the ‘Hetz Midget’ american arborvitae was alleviated when diuron was applied with any of the three mulches as a carrier. Pine bark treatments increased plant biomass for ‘Goldflame’ spirea in 2003, 45 DAT. At 120 DAT in 2002, pine bark gave increased plant biomass as compared with no organic mulch treatments for ‘Goldflame’ spirea. The study was conducted to ascertain whether the use of organic mulches as carriers could reduce phytotoxic effects of a herbicide on container-grown woody ornamentals, improve crop plant biomass, and act as a herbicide carrier for container-grown woody ornamentals.
- Published
- 2007
50. New Fast and Accurate 3D Micro Computed Tomography Technology for Digital Core Analysis
- Author
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Alexander Katsevich, M. Frenkel, Z. Huang, M. Feser, Allen Gu, T. Case, M. Andrew, and W. Thompson
- Subjects
Core (optical fiber) ,Optics ,medicine.diagnostic_test ,business.industry ,Computer science ,Micro computed tomography ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,medicine ,Industrial computed tomography ,Computed tomography ,business ,Nuclear medicine ,Micro ct - Abstract
Micro Computed Tomography (micro-CT) of cores is an emerging technology that yields vital information about key rock and fluid properties at pore-scale resolution. Micro-CT imaging results presented to date are encouraging and indicate that this technology has the potential to revolutionize petrophysical analysis and reservoir engineering. The application of micro-CT in petroleum engineering requires reconstructed scan data to be of high and uniform image quality to enable reliable analysis during subsequent segmentation and numerical modeling. This is achievable in existing micro-CT systems using standard circular scan trajectories with non-exact filtered backprojection (FBP) reconstruction, but requires small cone angles to keep cone beam artifacts below detectable limits. We describe the implementation and results of adapting an exact helical FBP reconstruction algorithm (the so-called “Katsevich Algorithm” or KFBP) and data acquisition scheme on a high-performance micro-CT system normally running in circular scan trajectory mode. Side-by-side comparisons of stitched circular scan trajectories with continuous helical scan trajectories on simulated and real rock core data show the throughput advantage of this modality for applications relevant for the petroleum industry keeping equivalent image quality to low cone angle circular scans. The analytical exact helical reconstruction can be performed in quasi-real time leading to instantaneous results. Simulated and experimental results indicate that an imaging throughput improvement of 2-5 times can be achieved employing KFBP-based exact helical reconstruction compared to the standard circle scan trajectory when imaging whole rock cores/plugs that are significantly longer than their diameter.
- Published
- 2015
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