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Pinsker R, Austin M, Ernst D, Garofalo A, Grierson B, Hosea J, Luce T, Marinoni A, McKee G, Perkins R, Petty C, Porkolab M, Rost J, Schmitz L, Solomon W, Taylor G, Turco F. Application of ECH to the Study of Transport in ITER Baseline Scenario-like Discharges in DIII-D. EPJ WEB OF CONFERENCES 2015. [DOI: 10.1051/epjconf/20158702003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Gambichler T, Segert H, Höxtermann S, Schmitz L, Altmeyer P, Teegen B. Neurological disorders in patients with bullous pemphigoid: clinical and experimental investigations. J Eur Acad Dermatol Venereol 2015; 29:1758-62. [PMID: 25651418 DOI: 10.1111/jdv.12995] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Accepted: 01/07/2015] [Indexed: 01/11/2023]
Abstract
BACKGROUND Previous studies have shown that patients with bullous pemphigoid (BP) are more likely to have neurological diseases (ND). OBJECTIVES To compare clinical findings in BP patients with and without ND and to investigate BP180 autoantibody binding in different neuronal tissues of mammalians. METHODS Our database was searched for clinical findings of in-patients with the definitive diagnosis of BP. Moreover, brain tissue of mammalians was treated with serum of BP patients with elevated BP180 autoantibodies using biochip mosaics. RESULTS Of 85/161 (52.8%) patients had a history of at least one ND (BP+ND). BP180 (P = 0.018), eosinophils (P = 0.043) and patients' accommodation in nursing homes (P < 0.0001) remained in the logistic regression model as significant independent predictors for the presence of ND in patients with BP. Subgroup analysis of community-dwelling BP patients revealed 25/93 (26.9%) patients with ND. In this population, the presence of ND also significantly correlated with BP180 (r = 0.26; P = 0.0003) and eosinophils (r = 0.19; P = 0.0087). In the animal model, no BP180-specific immunofluorescence could be detected. CONCLUSIONS Our data support results of previous studies detecting significantly increased frequency of ND in BP patients. We have shown that raised BP180 titres and blood eosinophils are independent predictors for the presence of ND in BP patients. However, our experimental data do not support previous results indicating that specific binding of BP180 antibodies in neuronal tissue plays a pathogenetic role in ND.
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Bardóczi L, Bencze A, Berta M, Schmitz L. Experimental confirmation of self-regulating turbulence paradigm in two-dimensional spectral condensation. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 90:063103. [PMID: 25615202 DOI: 10.1103/physreve.90.063103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Indexed: 06/04/2023]
Abstract
Turbulent transport in magnetic fusion plasmas can be significantly suppressed by Reynolds-stress-induced zonal flows, allowing effective plasma confinement. We present experimental evidence of spatiotemporal correlation between small-scale turbulence-induced Reynolds stress and large-scale zonal flow production in the E×B driven hydrodynamic spectral condensation. We show that Reynolds stress is generated effectively by anisotropic vorticity structures possessing collective tilt angle. The maximum amplitude of the tilt, the Reynolds stress, and the mean zonal flow production coincide with the transition time of the velocity field, indicating a key role of turbulence-induced Reynolds stress in the condensation of the flow. The analysis of the energy transfer between turbulence and zonal flow shows coherent oscillations with π/2 phase delay, thus indicating a predator-prey-like interaction between zonal flow and turbulence.
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Schmitz L, Ruskov E, Deng BH, Gota H, Gupta D, Tuszewski M, Douglass J, Peebles WA, Binderbauer M, Tajima T. Multi-channel Doppler backscattering measurements in the C-2 field reversed configuration. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:11D840. [PMID: 25430253 DOI: 10.1063/1.4891415] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A versatile heterodyne Doppler Backscattering (DBS) system is used to measure density fluctuation levels (in the wavenumber range kρs ≤ 50), and the toroidal E × B flow velocity in the C-2 Field-Reversed Configuration (FRC). Six tunable frequencies in three waveguide bands (26 GHz ≤ f ≤ 90 GHz) are launched using monostatic beam optics, via a quasi-optical beam combiner/polarizer and an adjustable parabolic focusing mirror (inside the vacuum enclosure) achieving Gaussian beam spot sizes of 3-5.5 cm at the X/O-mode cutoff. The DBS system covers plasma densities of 0.8 × 10(13) ≤ ne ≤ 1 × 10(14) cm(-3), and provides access to the FRC core (up to the field null) and across the FRC separatrix into the scrape-off layer plasma.
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Price SA, Schmitz L, Oufiero CE, Eytan RI, Dornburg A, Smith WL, Friedman M, Near TJ, Wainwright PC. Two waves of colonization straddling the K-Pg boundary formed the modern reef fish fauna. Proc Biol Sci 2014; 281:20140321. [PMID: 24695431 PMCID: PMC3996619 DOI: 10.1098/rspb.2014.0321] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Living reef fishes are one of the most diverse vertebrate assemblages on Earth. Despite its prominence and ecological importance, the origins and assembly of the reef fish fauna is poorly described. A patchy fossil record suggests that the major colonization of reef habitats must have occurred in the Late Cretaceous and early Palaeogene, with the earliest known modern fossil coral reef fish assemblage dated to 50 Ma. Using a phylogenetic approach, we analysed the early evolutionary dynamics of modern reef fishes. We find that reef lineages successively colonized reef habitats throughout the Late Cretaceous and early Palaeogene. Two waves of invasion were accompanied by increasing morphological convergence: one in the Late Cretaceous from 90 to 72 Ma and the other immediately following the end-Cretaceous mass extinction. The surge in reef invasions after the Cretaceous–Palaeogene boundary continued for 10 Myr, after which the pace of transitions to reef habitats slowed. Combined, these patterns match a classic niche-filling scenario: early transitions to reefs were made rapidly by morphologically distinct lineages and were followed by a decrease in the rate of invasions and eventual saturation of morphospace. Major alterations in reef composition, distribution and abundance, along with shifts in climate and oceanic currents, occurred during the Late Cretaceous and early Palaeogene interval. A causal mechanism between these changes and concurrent episodes of reef invasion remains obscure, but what is clear is that the broad framework of the modern reef fish fauna was in place within 10 Myr of the end-Cretaceous extinction.
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Spriestersbach H, Berger F, Schmitz L. 2D Strain: The Choice of the Width of the Region of Interest Has in Itself a Significant Influence on Measured Strain. Thorac Cardiovasc Surg 2013. [DOI: 10.1055/s-0033-1354539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Schmitz L, Bierhoff E, Dirschka T. Optical Coherence Tomography Imaging of Erythroplasia of Queyrat and Treatment with Imiquimod 5% Cream: A Case Report. Dermatology 2013; 228:24-6. [DOI: 10.1159/000354652] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Accepted: 07/27/2013] [Indexed: 11/19/2022] Open
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Gota H, Tuszewski M, Smirnov A, Korepanov S, Akhmetov T, Ivanov A, Voskoboynikov R, Binderbauer MW, Guo HY, Barnes D, Aefsky S, Brown R, Bui DQ, Clary R, Conroy KD, Deng BH, Dettrick SA, Douglass JD, Garate E, Glass FJ, Gupta D, Gupta S, Kinley JS, Knapp K, Hollins M, Longman A, Li XL, Luo Y, Mendoza R, Mok Y, Necas A, Primavera S, Osin D, Rostoker N, Ruskov E, Schmitz L, Schroeder JH, Sevier L, Sibley A, Song Y, Sun X, Tajima T, Thompson MC, Trask E, Van Drie AD, Walters JK, Wyman MD, Zhai K. A High Performance Field-Reversed Configuration Regime in the C-2 Device. FUSION SCIENCE AND TECHNOLOGY 2013. [DOI: 10.13182/fst13-a16890] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Hillesheim JC, DeBoo JC, Peebles WA, Carter TA, Wang G, Rhodes TL, Schmitz L, McKee GR, Yan Z, Staebler GM, Burrell KH, Doyle EJ, Holland C, Petty CC, Smith SP, White AE, Zeng L. Observation of a critical gradient threshold for electron temperature fluctuations in the DIII-D Tokamak. PHYSICAL REVIEW LETTERS 2013; 110:045003. [PMID: 25166172 DOI: 10.1103/physrevlett.110.045003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Indexed: 06/03/2023]
Abstract
A critical gradient threshold has been observed for the first time in a systematic, controlled experiment for a locally measured turbulent quantity in the core of a confined high-temperature plasma. In an experiment in the DIII-D tokamak where L(T(e))(-1) = |∇T(e)|/T(e) and toroidal rotation were varied, long wavelength (k(θ)ρ(s) ≲ 0.4) electron temperature fluctuations exhibit a threshold in L(T(e))(-1): below, they change little; above, they steadily increase. The increase in δT(e)/T(e) is concurrent with increased electron heat flux and transport stiffness. Observations were insensitive to rotation. Accumulated evidence strongly enforces the identification of the experimentally observed threshold with ∇T(e)-driven trapped electron mode turbulence.
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Claus M, Schmitz L, Roman A, Stevens E, Dechamps P. No association between vitamin D deficiency at admission and outcome in a medical ICU. Crit Care 2012. [PMCID: PMC3363571 DOI: 10.1186/cc10760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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61
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Hillesheim JC, Holland C, Schmitz L, Kubota S, Rhodes TL, Carter TA. 2D full wave modeling for a synthetic Doppler backscattering diagnostic. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2012; 83:10E331. [PMID: 23126989 DOI: 10.1063/1.4733549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Doppler backscattering (DBS) is a plasma diagnostic used in tokamaks and other magnetic confinement devices to measure the fluctuation level of intermediate wavenumber (k(θ)ρ(s) ~ 1) density fluctuations and the lab frame propagation velocity of turbulence. Here, a synthetic DBS diagnostic is described, which has been used for comparisons between measurements in the DIII-D tokamak and predictions from nonlinear gyrokinetic simulations. To estimate the wavenumber range to which a Gaussian beam would be sensitive, a ray tracing code and a 2D finite difference, time domain full wave code are used. Experimental density profiles and magnetic geometry are used along with the experimental antenna and beam characteristics. An example of the effect of the synthetic diagnostic on the output of a nonlinear gyrokinetic simulation is presented.
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Tuszewski M, Smirnov A, Thompson MC, Korepanov S, Akhmetov T, Ivanov A, Voskoboynikov R, Schmitz L, Barnes D, Binderbauer MW, Brown R, Bui DQ, Clary R, Conroy KD, Deng BH, Dettrick SA, Douglass JD, Garate E, Glass FJ, Gota H, Guo HY, Gupta D, Gupta S, Kinley JS, Knapp K, Longman A, Hollins M, Li XL, Luo Y, Mendoza R, Mok Y, Necas A, Primavera S, Ruskov E, Schroeder JH, Sevier L, Sibley A, Song Y, Sun X, Trask E, Van Drie AD, Walters JK, Wyman MD. Field reversed configuration confinement enhancement through edge biasing and neutral beam injection. PHYSICAL REVIEW LETTERS 2012; 108:255008. [PMID: 23004613 DOI: 10.1103/physrevlett.108.255008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Indexed: 06/01/2023]
Abstract
Field reversed configurations (FRCs) with high confinement are obtained in the C-2 device by combining plasma gun edge biasing and neutral beam injection. The plasma gun creates an inward radial electric field that counters the usual FRC spin-up. The n = 2 rotational instability is stabilized without applying quadrupole magnetic fields. The FRCs are nearly axisymmetric, which enables fast ion confinement. The plasma gun also produces E × B shear in the FRC edge layer, which may explain the observed improved particle transport. The FRC confinement times are improved by factors 2 to 4, and the plasma lifetimes are extended from 1 to up to 4 ms.
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Schmitz L, Zeng L, Rhodes TL, Hillesheim JC, Doyle EJ, Groebner RJ, Peebles WA, Burrell KH, Wang G. Role of zonal flow predator-prey oscillations in triggering the transition to H-mode confinement. PHYSICAL REVIEW LETTERS 2012; 108:155002. [PMID: 22587261 DOI: 10.1103/physrevlett.108.155002] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Indexed: 05/31/2023]
Abstract
Direct evidence of zonal flow (ZF) predator-prey oscillations and the synergistic roles of ZF- and equilibrium E×B flow shear in triggering the low- to high-confinement (L- to H-mode) transition in the DIII-D tokamak is presented. Periodic turbulence suppression is first observed in a narrow layer at and just inside the separatrix when the shearing rate transiently exceeds the turbulence decorrelation rate. The final transition to H mode with sustained turbulence and transport reduction is controlled by equilibrium E×B shear due to the increasing ion pressure gradient.
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Schmitz L. Letter Re: Feder et al Article. Clin Infect Dis 2012; 54:886-7; author reply 888-9. [DOI: 10.1093/cid/cir1008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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65
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Grieb G, Simons D, Schmitz L, Piatkowski A, Grottke O, Pallua N. O17.4 Glasgow Coma Scale and laboratory markers superior to COHb in predicting CO intoxication severity? Burns 2011. [DOI: 10.1016/s0305-4179(11)70048-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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66
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Schmitz L, Motani R. Nocturnality in Dinosaurs Inferred from Scleral Ring and Orbit Morphology. Science 2011; 332:705-8. [DOI: 10.1126/science.1200043] [Citation(s) in RCA: 111] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Otten J, Schmitz L, Vettorazzi E, Schultze A, Marx AH, Simon R, Krauter J, Loges S, Sauter G, Bokemeyer C, Fiedler W. Expression of TGF-β receptor ALK-5 has a negative impact on outcome of patients with acute myeloid leukemia. Leukemia 2010; 25:375-9. [PMID: 21304536 DOI: 10.1038/leu.2010.273] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Hillesheim JC, Peebles WA, Rhodes TL, Schmitz L, White AE, Carter TA. New plasma measurements with a multichannel millimeter-wave fluctuation diagnostic system in the DIII-D tokamak (invited). THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:10D907. [PMID: 21033939 DOI: 10.1063/1.3466900] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A novel multichannel, tunable Doppler backscattering (DBS)/reflectometry system has recently been developed and applied to a variety of DIII-D plasmas. Either DBS or reflectometry can be easily configured for use in a wide range of plasma conditions using a flexible quasi-optical antenna system. The multiple closely spaced channels, when combined with other fluctuation diagnostic systems, have opened up new measurements of plasma properties. For example, the toroidal and fine-scale radial structure of coherent plasma oscillations, such as geodesic acoustic modes, have been probed simultaneously in the core of high temperature plasmas by applying correlation analysis between two toroidally separated DBS systems, as well as within the multichannel array. When configured as a reflectometer, cross-correlation with electron cyclotron emission radiometry has uncovered detailed information regarding the crossphase relationship between density and temperature fluctuations. The density-temperature crossphase measurement yields insight into the physics of tokamak turbulence at a fundamental level that can be directly compared with predictions from nonlinear gyrokinetic simulations.
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Rhodes TL, Peebles WA, Nguyen X, Hillesheim JC, Schmitz L, White AE, Wang G. Quasioptical design of integrated Doppler backscattering and correlation electron cyclotron emission systems on the DIII-D tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:10D912. [PMID: 21033944 DOI: 10.1063/1.3475797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The quasioptical design of a new integrated Doppler backscattering (DBS) and correlation electron cyclotron emission (CECE) system is presented. The design provides for simultaneous measurements of intermediate wavenumber density and long wavelength electron temperature turbulence behavior. The Doppler backscattering technique is sensitive to plasma turbulence flow and has been utilized to determine radial electric field, geodesic acoustic modes, zonal flows, and intermediate scale (k∼1-6 cm(-1)) density turbulence. The correlation ECE system measures a second turbulent field, electron temperature fluctuations, and is sensitive to long poloidal wavelength (k≤1.8 cm(-1)). The integrated system utilizes a newly installed in-vessel focusing mirror that produces a beam waist diameter of 3.5-5 cm in the plasma depending on the frequency. A single antenna (i.e., monostatic operation) is used for both launch and receive. The DBS wavenumber is selected via an adjustable launch angle and variable probing frequency. Due to the unique system design both positive and negative wavenumbers can be obtained, with a range of low to intermediate wavenumbers possible (approximately -3 to 10 cm(-1)). A unique feature of the design is the ability to place the DBS and CECE measurements at the same radial and poloidal locations allowing for cross correlation studies (e.g., measurement of nT cross-phase).
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Binderbauer MW, Guo HY, Tuszewski M, Putvinski S, Sevier L, Barnes D, Rostoker N, Anderson MG, Andow R, Bonelli L, Brandi F, Brown R, Bui DQ, Bystritskii V, Ceccherini F, Clary R, Cheung AH, Conroy KD, Deng BH, Dettrick SA, Douglass JD, Feng P, Galeotti L, Garate E, Giammanco F, Glass FJ, Gornostaeva O, Gota H, Gupta D, Gupta S, Kinley JS, Knapp K, Korepanov S, Hollins M, Isakov I, Jose VA, Li XL, Luo Y, Marsili P, Mendoza R, Meekins M, Mok Y, Necas A, Paganini E, Pegoraro F, Pousa-Hijos R, Primavera S, Ruskov E, Qerushi A, Schmitz L, Schroeder JH, Sibley A, Smirnov A, Song Y, Sun X, Thompson MC, Van Drie AD, Walters JK, Wyman MD. Dynamic formation of a hot field reversed configuration with improved confinement by supersonic merging of two colliding high-β compact toroids. PHYSICAL REVIEW LETTERS 2010; 105:045003. [PMID: 20867853 DOI: 10.1103/physrevlett.105.045003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2010] [Indexed: 05/29/2023]
Abstract
A hot stable field-reversed configuration (FRC) has been produced in the C-2 experiment by colliding and merging two high-β plasmoids preformed by the dynamic version of field-reversed θ-pinch technology. The merging process exhibits the highest poloidal flux amplification obtained in a magnetic confinement system (over tenfold increase). Most of the kinetic energy is converted into thermal energy with total temperature (T{i}+T{e}) exceeding 0.5 keV. The final FRC state exhibits a record FRC lifetime with flux confinement approaching classical values. These findings should have significant implications for fusion research and the physics of magnetic reconnection.
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Czernik C, Rhode S, Metze B, Schmitz L, Bührer C. Linksventrikuläre echokardiographische Parameter bei hypotrophen und eutrophen Frühgeborenen ≤32 SSW. KLINISCHE PADIATRIE 2010. [DOI: 10.1055/s-0030-1261368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Schmitz L, Suball M, Hanicq C, El-Mahi T, Piersoel V, Stevens E, Roman A. Therapeutic impact on intravenous insulin dosing with three new point-of-care glucose meters in an adult ICU. Crit Care 2010. [PMCID: PMC2934201 DOI: 10.1186/cc8805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Hillesheim JC, Peebles WA, Rhodes TL, Schmitz L, Carter TA, Gourdain PA, Wang G. A multichannel, frequency-modulated, tunable Doppler backscattering and reflectometry system. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2009; 80:083507. [PMID: 19725655 DOI: 10.1063/1.3205449] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A novel multichannel Doppler backscattering system has been designed and tested for application on the DIII-D [J. L. Luxon, Fusion Sci. Technol. 48, 828 (2005)] and National Spherical Torus Experiment (NSTX) [M. Ono et al., Nucl. Fusion 40, 557 (2000)] fusion plasma devices. Doppler backscattering measures localized intermediate wavenumber (k(perpendicular)rho(i) approximately 1-4,k(perpendicular) approximately 2-15 cm(-1)) density fluctuations and the propagation velocity of turbulent structures. Microwave radiation is launched at a frequency that approaches a cutoff layer in the plasma and at an angle that is oblique to the cutoff layer. Bragg backscattering occurs near the cutoff layer for fluctuations with k(perpendicular) approximately -2k(i), where k(i) is the incident probe wave vector at the scattering location. The turbulence propagation velocity can be determined from the Doppler shift in the return signal together with knowledge of the scattering wavenumber. Ray tracing simulations are used to determine k(perpendicular) and the scattering location. Frequency modulation of a voltage-controlled solid state microwave source followed by frequency multiplication is used to create an array of finely spaced (Delta f=350 MHz) frequencies spanning 1.4 GHz. The center of the array bandwidth is tunable within the range of approximately 53-78 GHz. This article details the system design, laboratory tests, and presents initial data from DIII-D plasmas.
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Czernik C, Metze B, Schmitz L, Sarioglu N, Henrich W, Bührer C. Hydrops fetalis – Wandel von Diagnosespektrum und Prognose? Z Geburtshilfe Neonatol 2009. [DOI: 10.1055/s-0029-1223048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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75
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Münch A, Schmitz L, Schulze-Neick I, Loui A, Pohl-Schickinger A. Sildenafil – Eine Option bei Frühgeborenen mit schwerer bronchopulmonaler Dysplasie? Z Geburtshilfe Neonatol 2009. [DOI: 10.1055/s-0029-1223104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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