The direct measurement of the heteronuclear chemical shifts relative to tetramethylsilane

International Nuclear Information System (INIS)

Moritz, A.G.

1988-12-01

The measurement of heteronuclear chemical shifts using absolute frequencies of the heteronucleus and the 1 H resonance of tetramethylsilane has been examined. This method avoids the problems associated with external standards and gives results which can be obtained quickly and with high precision. The method has a number of advantages in the accurate measurement of chemical shifts, as for example 31 P in chemical warfare agents and related chemicals and allows multinuclear data to be obtained without dynamic range or potential interference problems. 15 refs., 4 tabs

Application of heteronuclear couplings to conformational analysis of oligonucleotides

International Nuclear Information System (INIS)

Zhu, G.; Live, D.; Bax, A.

1994-01-01

The value of vicinal coupling constants extracted from NMR spectra in deducing torsion angles for conformational analysis is well recognized. Due to the abundance of protons, their couplings have been mostly widely used. In many instances, couplings between protons and other nuclei may be a valuable complement to proton-proton couplings or, in some instances, may be the only coupling available to characterize the torsion angle about a bond. Recently, heteronuclear couplings have been used to great benefit in studies of isotopically enriched proteins, and this general approach has been extended to peptides at natural abundance. The possibility of using this approach to study oligonucleotides is also attractive but has not as yet been widely exploited. With the development of strategies for labeling such molecules, particularly RNAs, this may become an important component in conformational analysis. For DNA, labeling is less accessible, but sufficient quantities of unlabeled material are readily available for measuring these couplings at natural abundance. We chose several DNA systems to explore the usefulness of heteronuclear couplings in addressing the sugar conformation and the glycosidic torsion angle. Intensities of cross peaks in long-range HMQC experiments can be related to the couplings. Crosspeaks involving H1' and C1' atoms have been emphasized because of the superior shift dispersion at these positions between sugar protons and carbon atoms. Results will be shown for the self-complementary Dickerson duplex dodecamer sequence d(CGCGAATTCGCG) and for d(GGTCGG), which dimerizes to form a G-tetrad structure incorporating both syn and anti base orientations. The couplings provide a clear discrimination between presence of C3'-endo and C2'-endo conformations of the sugars and syn and anti bases arrangements

Application of heteronuclear couplings to conformational analysis of oligonucleotides

Energy Technology Data Exchange (ETDEWEB)

Zhu, G. [Univ. of Maryland, College Park, MD (United States); Live, D. [Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Bax, A. [NIDDK National Institutes of Health, Bethesda, MD (United States)

1994-12-01

The value of vicinal coupling constants extracted from NMR spectra in deducing torsion angles for conformational analysis is well recognized. Due to the abundance of protons, their couplings have been mostly widely used. In many instances, couplings between protons and other nuclei may be a valuable complement to proton-proton couplings or, in some instances, may be the only coupling available to characterize the torsion angle about a bond. Recently, heteronuclear couplings have been used to great benefit in studies of isotopically enriched proteins, and this general approach has been extended to peptides at natural abundance. The possibility of using this approach to study oligonucleotides is also attractive but has not as yet been widely exploited. With the development of strategies for labeling such molecules, particularly RNAs, this may become an important component in conformational analysis. For DNA, labeling is less accessible, but sufficient quantities of unlabeled material are readily available for measuring these couplings at natural abundance. We chose several DNA systems to explore the usefulness of heteronuclear couplings in addressing the sugar conformation and the glycosidic torsion angle. Intensities of cross peaks in long-range HMQC experiments can be related to the couplings. Crosspeaks involving H1{prime} and C1{prime} atoms have been emphasized because of the superior shift dispersion at these positions between sugar protons and carbon atoms. Results will be shown for the self-complementary Dickerson duplex dodecamer sequence d(CGCGAATTCGCG) and for d(GGTCGG), which dimerizes to form a G-tetrad structure incorporating both syn and anti base orientations. The couplings provide a clear discrimination between presence of C3{prime}-endo and C2{prime}-endo conformations of the sugars and syn and anti bases arrangements.

Two-pass dual-energy CT imaging for simultaneous detection, characterization, and volume measurement of urinary stones with excretory-phase CT urography alone. A phantom study

International Nuclear Information System (INIS)

Takahashi, Satoru; Niikawa, Hidekazu; Shikata, Atsushi; Murakami, Emi; Tsunoda, Hiroshi; Yoshioka, Toshiaki; Yamamoto, Hiroshi; Itoh, Toshihide; Tsujihata, Masao

2013-01-01

The purpose of this study was to evaluate if two-pass dual-energy CT imaging - id est (i.e.), simultaneous three-material and two-material decomposition analysis - can depict and characterize urinary stones in various concentrations of iodine solution in vitro. Twelve urinary stones were scanned with a dual-source CT scanner. First, each stone (in a saline-filled tube) underwent single- and dual-energy mode CT scans in order to measure the volume of the stone. Each stone was then placed in various concentrations of contrast medium and scanned in dual-energy mode to calculate its volume via three-material decomposition analysis. Two-pass dual-energy CT imaging analysis software for the Matlab environment, which was developed specifically to process simultaneous three-material and two-material decomposition, was applied to characterize and calculate the volume of each stone. Although the virtual non-contrast images from three-material decomposition analysis clearly visualized all of the stones in contrast medium with up to 80 mgI/mL, the volumes of the uric acid stones were overestimated. Two-pass dual-energy CT imaging was able to depict and characterize non-uric-acid stones in diluted contrast medium with up to 80 mgI/mL, whereas uric acid stones were correctly evaluated in diluted contrast medium with 40 mgI/mL or less. Two-pass dual-energy CT imaging is able to depict and characterize urinary stones in contrast medium. (author)

Large volume serial section tomography by Xe Plasma FIB dual beam microscopy

International Nuclear Information System (INIS)

Burnett, T.L.; Kelley, R.; Winiarski, B.; Contreras, L.; Daly, M.; Gholinia, A.; Burke, M.G.; Withers, P.J.

2016-01-01

Ga + Focused Ion Beam-Scanning Electron Microscopes (FIB-SEM) have revolutionised the level of microstructural information that can be recovered in 3D by block face serial section tomography (SST), as well as enabling the site-specific removal of smaller regions for subsequent transmission electron microscope (TEM) examination. However, Ga + FIB material removal rates limit the volumes and depths that can be probed to dimensions in the tens of microns range. Emerging Xe + Plasma Focused Ion Beam-Scanning Electron Microscope (PFIB-SEM) systems promise faster removal rates. Here we examine the potential of the method for large volume serial section tomography as applied to bainitic steel and WC–Co hard metals. Our studies demonstrate that with careful control of milling parameters precise automated serial sectioning can be achieved with low levels of milling artefacts at removal rates some 60× faster. Volumes that are hundreds of microns in dimension have been collected using fully automated SST routines in feasible timescales (<24 h) showing good grain orientation contrast and capturing microstructural features at the tens of nanometres to the tens of microns scale. Accompanying electron back scattered diffraction (EBSD) maps show high indexing rates suggesting low levels of surface damage. Further, under high current Ga + FIB milling WC–Co is prone to amorphisation of WC surface layers and phase transformation of the Co phase, neither of which have been observed at PFIB currents as high as 60 nA at 30 kV. Xe + PFIB dual beam microscopes promise to radically extend our capability for 3D tomography, 3D EDX, 3D EBSD as well as correlative tomography. - Highlights: • The uptake of dual beam FIBs has been rapid but long milling times have limited imaged volumes to tens of micron dimensions. • Emerging plasma Xe + PFIB-SEM technology offers materials removal rates at least 60× greater than conventional Ga + FIB systems with comparable or less damage. • The

S³ HMBC hetero: Spin-State-Selective HMBC for accurate measurement of long-range heteronuclear coupling constants

DEFF Research Database (Denmark)

Hoeck, Casper; Gotfredsen, Charlotte Held; Sørensen, Ole W.

2017-01-01

A novel method, Spin-State-Selective (S3) HMBC hetero, for accurate measurement of heteronuclear coupling constants is introduced. The method extends the S3 HMBC technique for measurement of homonuclear coupling constants by appending a pulse sequence element that interchanges the polarization...

Heteronuclear proton assisted recoupling

Science.gov (United States)

De Paëpe, Gaël; Lewandowski, Józef R.; Loquet, Antoine; Eddy, Matt; Megy, Simon; Böckmann, Anja; Griffin, Robert G.

2011-03-01

We describe a theoretical framework for understanding the heteronuclear version of the third spin assisted recoupling polarization transfer mechanism and demonstrate its potential for detecting long-distance intramolecular and intermolecular 15N-13C contacts in biomolecular systems. The pulse sequence, proton assisted insensitive nuclei cross polarization (PAIN-CP) relies on a cross term between 1H-15N and 1H-13C dipolar couplings to mediate zero- and/or double-quantum 15N-13C recoupling. In particular, using average Hamiltonian theory we derive effective Hamiltonians for PAIN-CP and show that the transfer is mediated by trilinear terms of the form N±C∓Hz (ZQ) or N±C±Hz (DQ) depending on the rf field strengths employed. We use analytical and numerical simulations to explain the structure of the PAIN-CP optimization maps and to delineate the appropriate matching conditions. We also detail the dependence of the PAIN-CP polarization transfer with respect to local molecular geometry and explain the observed reduction in dipolar truncation. In addition, we demonstrate the utility of PAIN-CP in structural studies with 15N-13C spectra of two uniformly 13C,15N labeled model microcrystalline proteins—GB1, a 56 amino acid peptide, and Crh, a 85 amino acid domain swapped dimer (MW = 2 × 10.4 kDa). The spectra acquired at high magic angle spinning frequencies (ωr/2π > 20 kHz) and magnetic fields (ω0H/2π = 700-900 MHz) using moderate rf fields, yield multiple long-distance intramonomer and intermonomer 15N-13C contacts. We use these distance restraints, in combination with the available x-ray structure as a homology model, to perform a calculation of the monomer subunit of the Crh protein.

Phase behaviour of heteronuclear dimers in three-dimensional systems-a Monte Carlo study

International Nuclear Information System (INIS)

Rzysko, W; Binder, K

2008-01-01

Monte Carlo simulation in the grand canonical ensemble, the histogram reweighting technique and finite size scaling are used to study the phase behaviour of dimers in three-dimensional systems. A single molecule is composed of two segments A and B, and the bond between them cannot be broken. The phase diagrams have been estimated for a set of model systems. Different structures formed by heteronuclear dimers have been found. The results show a great variety of vapour-liquid coexistence behaviour depending on the strength of the interactions between segments

Heteronuclear long-range correlation, what’s new and how far can it take us?

DEFF Research Database (Denmark)

Sørensen, Ole W.

: A novel experiment for small-molecule and biomolecular NMR at natural isotopic abundance. Sebastian Meier, Andrew J. Benie, Jens Ø. Duus and Ole W. Sørensen, Journal of Magnetic Resonance, in press, doi:10.1016/j.jmr.2009.06.017 Recent progress in heteronuclear long-range NMR of complex carbohydrates: 3D...... H2BC and clean HMBC. Sebastian Meier, Bent O. Petersen, Jens Ø. Duus, Ole W. Sørensen. Carbohydrate Research, in press, doi:10.1016/j.carres.2009.08.013...

Interaction-induced decay of a heteronuclear two-atom system

Science.gov (United States)

Xu, Peng; Yang, Jiaheng; Liu, Min; He, Xiaodong; Zeng, Yong; Wang, Kunpeng; Wang, Jin; Papoular, D. J.; Shlyapnikov, G. V.; Zhan, Mingsheng

2015-01-01

Two-atom systems in small traps are of fundamental interest for understanding the role of interactions in degenerate cold gases and for the creation of quantum gates in quantum information processing with single-atom traps. One of the key quantities is the inelastic relaxation (decay) time when one of the atoms or both are in a higher hyperfine state. Here we measure this quantity in a heteronuclear system of 87Rb and 85Rb in a micro optical trap and demonstrate experimentally and theoretically the presence of both fast and slow relaxation processes, depending on the choice of the initial hyperfine states. This experimental method allows us to single out a particular relaxation process thus provides an extremely clean platform for collisional physics studies. Our results have also implications for engineering of quantum states via controlled collisions and creation of two-qubit quantum gates. PMID:26199051

Dual Energy CT Angiography of Peripheral Arterial Disease: Feasibility of Using Lower Contrast Medium Volume.

Directory of Open Access Journals (Sweden)

Abdulrahman Almutairi

Full Text Available One of the main drawbacks associated with Dual Energy Computed Tomography Angiography (DECTA is the risk of developing contrast medium-induced nephropathy (CIN. The aim of the present study was firstly, to design an optimal CT imaging protocol by determining the feasibility of using a reduced contrast medium volume in peripheral arterial DECTA, and secondly, to compare the results with those obtained from using routine contrast medium volume.Thirty four patients underwent DECTA for the diagnosis of peripheral arterial disease. They were randomly divided into two groups: Group 1 (routine contrast volume group with n = 17, injection rate 4-5 ml/s, and 1.5 ml/kg of contrast medium, and Group 2 ((low contrast volume group, with n = 17, injection rate 4-5ml/s, and contrast medium volume 0.75 ml/kg. A fast kilovoltage-switching 64-slice CT scanner in the dual-energy mode was employed for the study. A total of 6 datasets of monochromatic images at 50, 55, 60, 65, 70 and 75 keV levels were reconstructed with adaptive statistical iterative reconstruction (ASIR at 50%. A 4-point scale was the tool for qualitative analysis of results. The two groups were compared and assessed quantitatively for image quality on the basis of signal-to-noise ratio (SNR and contrast-to-noise-ratio (CNR. Radiation and contrast medium doses were also compared.The overall mean CT attenuation and mean noise for all lower extremity body parts was significantly lower for the low volume contrast group (p<0.001, and varied significantly between groups (p = 0.001, body parts (p<0.001 and keVs (p<0.001. The interaction between group body parts was significant with CT attenuation and CNR (p = 0.002 and 0.003 respectively, and marginally significant with SNR (p = 0.047, with minimal changes noticed between the two groups. Group 2 (low contrast volume group displayed the lowest image noise between 65 and 70 keV, recorded the highest SNR and CNR at 65 keV, and produced significantly lower

Large volume serial section tomography by Xe Plasma FIB dual beam microscopy

Energy Technology Data Exchange (ETDEWEB)

Burnett, T.L. [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); FEI Company, Achtseweg Noord 5, Bldg, 5651 GG, Eindhoven (Netherlands); Kelley, R. [FEI Company, 5350 NE Dawson Creek Drive, Hillsboro, OR 97124 (United States); Winiarski, B. [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); FEI Company, Achtseweg Noord 5, Bldg, 5651 GG, Eindhoven (Netherlands); Contreras, L. [FEI Company, 5350 NE Dawson Creek Drive, Hillsboro, OR 97124 (United States); Daly, M.; Gholinia, A.; Burke, M.G. [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); Withers, P.J., E-mail: P.J.Withers@manchester.ac.uk [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); BP International Centre for Advanced Materials, University of Manchester, Manchester M13 9PL (United Kingdom)

2016-02-15

Ga{sup +} Focused Ion Beam-Scanning Electron Microscopes (FIB-SEM) have revolutionised the level of microstructural information that can be recovered in 3D by block face serial section tomography (SST), as well as enabling the site-specific removal of smaller regions for subsequent transmission electron microscope (TEM) examination. However, Ga{sup +} FIB material removal rates limit the volumes and depths that can be probed to dimensions in the tens of microns range. Emerging Xe{sup +} Plasma Focused Ion Beam-Scanning Electron Microscope (PFIB-SEM) systems promise faster removal rates. Here we examine the potential of the method for large volume serial section tomography as applied to bainitic steel and WC–Co hard metals. Our studies demonstrate that with careful control of milling parameters precise automated serial sectioning can be achieved with low levels of milling artefacts at removal rates some 60× faster. Volumes that are hundreds of microns in dimension have been collected using fully automated SST routines in feasible timescales (<24 h) showing good grain orientation contrast and capturing microstructural features at the tens of nanometres to the tens of microns scale. Accompanying electron back scattered diffraction (EBSD) maps show high indexing rates suggesting low levels of surface damage. Further, under high current Ga{sup +} FIB milling WC–Co is prone to amorphisation of WC surface layers and phase transformation of the Co phase, neither of which have been observed at PFIB currents as high as 60 nA at 30 kV. Xe{sup +} PFIB dual beam microscopes promise to radically extend our capability for 3D tomography, 3D EDX, 3D EBSD as well as correlative tomography. - Highlights: • The uptake of dual beam FIBs has been rapid but long milling times have limited imaged volumes to tens of micron dimensions. • Emerging plasma Xe{sup +} PFIB-SEM technology offers materials removal rates at least 60× greater than conventional Ga{sup +} FIB systems with

Synthesis and magnetic properties of heteronuclear 3d-4f compound

International Nuclear Information System (INIS)

Cristovao, B.; Ferenc, W.

2007-01-01

A novel heteronuclear 3d-4f compound having formula NdCu 3 L 3 ·13H 2 O (where H 3 L = Schiff base derived from 5-bromosalicylaldehyde and glycylglycine and L 3 = C 11 H 8 N 2 O 4 Br) was obtained. It was characterized by elemental and thermal analyses and magnetic measurements. The Cu(II)-Nd(III) compound is stable up to 323 K. During dehydration process the water molecules are lost in two stages. The magnetic susceptibility data for this complex change with temperature according to the Curie-Weiss law with Θ = -35 K. The magnetic moment values decrease from 5.00μ B at 303 K to 4.38μB at 76 K. (author)

Quotient functions of dual quermassintegrals | Zhao | Quaestiones ...

African Journals Online (AJOL)

Motivated by the notion of volume difference functions, we introduce quotient functions of dual quermassintegrals and establish Brunn-Minkowski type inequalities for them, which have several recent results as special cases. Keywords: Volume difference function, dual quermassintegrals, quotient function, radial Blaschke ...

Dual-Use Space Technology Transfer Conference and Exhibition. Volume 2

Science.gov (United States)

Krishen, Kumar (Compiler)

1994-01-01

This is the second volume of papers presented at the Dual-Use Space Technology Transfer Conference and Exhibition held at the Johnson Space Center February 1-3, 1994. Possible technology transfers covered during the conference were in the areas of information access; innovative microwave and optical applications; materials and structures; marketing and barriers; intelligent systems; human factors and habitation; communications and data systems; business process and technology transfer; software engineering; biotechnology and advanced bioinstrumentation; communications signal processing and analysis; medical care; applications derived from control center data systems; human performance evaluation; technology transfer methods; mathematics, modeling, and simulation; propulsion; software analysis and decision tools; systems/processes in human support technology; networks, control centers, and distributed systems; power; rapid development; perception and vision technologies; integrated vehicle health management; automation technologies; advanced avionics; and robotics technologies.

L p -Dual geominimal surface area

Directory of Open Access Journals (Sweden)

Weidong Wang

2011-01-01

Full Text Available Abstract Lutwak proposed the notion of Lp -geominimal surface area according to the Lp -mixed volume. In this article, associated with the Lp -dual mixed volume, we introduce the Lp -dual geominimal surface area and prove some inequalities for this notion. 2000 Mathematics Subject Classification: 52A20 52A40.

Comparison of bone volume measurements using conventional single and dual energy computed tomography

International Nuclear Information System (INIS)

Kim, Yung Kyoon; Park, Sang Hoon; Kim, Yon Min

2017-01-01

The study examines changes in calcium volume on born by comparing two figures; one is measured by dual energy computed tomography(DECT) followed by applying variation in monochromatic energy selection( keV), material decomposition(MD), and material suppressed iodine(MSI) analysis, and the other is measured by conventional single source computed tomography(CSCT). For this study, based on CSCT images taken by using human mimicked phantom, 70, 100, 140 keV and MSI, MD material calcium weighting( MCW) and MD material iodine weighting(MIW) of DECT were applied respectively. Then calculated calcium volume was converted to Agatston score for comparison. Volume of human mimicked phantom was in inverse proportion to keV. The volume decreased while keV increased(p<0.05). The most similar DECT volumes were reconstructed at 70 keV, the difference was showed 35.8±12.2 for rib, femur (16.1±24.1), pelvis(13.7±18.8), and spine(179.0±61.8). However, the volume of MSI was down for each organ; the volume of rib was 5.55%, femur(76.34%), pelvis(55.16%) and spine(87.58%). The volume of MSI decreased 55.9% for rib, femur(80.7%), pelvis(69.6%) and spine(54.2%) while MD MIW reduced for rib(83.51%), femur(87.68%), pelvis(86.64%), and spine(82.62%). With the results, the study found that outcomes were affected by the method which examiners employed. When using DECT, calcium volume of born dropped with keV increased. It also found that the most similar DECT images were reconstructed at 70 keV. The results of experiments implied that the users of MSI and MD should be cautious of errors as there are big differences in scores between those two methods

Comparison of bone volume measurements using conventional single and dual energy computed tomography

Energy Technology Data Exchange (ETDEWEB)

Kim, Yung Kyoon; Park, Sang Hoon [Dept. of Radiology, Samsung Medical Center, Seoul (Korea, Republic of); Kim, Yon Min [Dept. of Radiotechnology, Wonkwang Health Science University, Iksan (Korea, Republic of)

2017-06-15

The study examines changes in calcium volume on born by comparing two figures; one is measured by dual energy computed tomography(DECT) followed by applying variation in monochromatic energy selection( keV), material decomposition(MD), and material suppressed iodine(MSI) analysis, and the other is measured by conventional single source computed tomography(CSCT). For this study, based on CSCT images taken by using human mimicked phantom, 70, 100, 140 keV and MSI, MD material calcium weighting( MCW) and MD material iodine weighting(MIW) of DECT were applied respectively. Then calculated calcium volume was converted to Agatston score for comparison. Volume of human mimicked phantom was in inverse proportion to keV. The volume decreased while keV increased(p<0.05). The most similar DECT volumes were reconstructed at 70 keV, the difference was showed 35.8±12.2 for rib, femur (16.1±24.1), pelvis(13.7±18.8), and spine(179.0±61.8). However, the volume of MSI was down for each organ; the volume of rib was 5.55%, femur(76.34%), pelvis(55.16%) and spine(87.58%). The volume of MSI decreased 55.9% for rib, femur(80.7%), pelvis(69.6%) and spine(54.2%) while MD MIW reduced for rib(83.51%), femur(87.68%), pelvis(86.64%), and spine(82.62%). With the results, the study found that outcomes were affected by the method which examiners employed. When using DECT, calcium volume of born dropped with keV increased. It also found that the most similar DECT images were reconstructed at 70 keV. The results of experiments implied that the users of MSI and MD should be cautious of errors as there are big differences in scores between those two methods.

Interactive dual-volume rendering visualization with real-time fusion and transfer function enhancement

Science.gov (United States)

Macready, Hugh; Kim, Jinman; Feng, David; Cai, Weidong

2006-03-01

Dual-modality imaging scanners combining functional PET and anatomical CT constitute a challenge in volumetric visualization that can be limited by the high computational demand and expense. This study aims at providing physicians with multi-dimensional visualization tools, in order to navigate and manipulate the data running on a consumer PC. We have maximized the utilization of pixel-shader architecture of the low-cost graphic hardware and the texture-based volume rendering to provide visualization tools with high degree of interactivity. All the software was developed using OpenGL and Silicon Graphics Inc. Volumizer, tested on a Pentium mobile CPU on a PC notebook with 64M graphic memory. We render the individual modalities separately, and performing real-time per-voxel fusion. We designed a novel "alpha-spike" transfer function to interactively identify structure of interest from volume rendering of PET/CT. This works by assigning a non-linear opacity to the voxels, thus, allowing the physician to selectively eliminate or reveal information from the PET/CT volumes. As the PET and CT are rendered independently, manipulations can be applied to individual volumes, for instance, the application of transfer function to CT to reveal the lung boundary while adjusting the fusion ration between the CT and PET to enhance the contrast of a tumour region, with the resultant manipulated data sets fused together in real-time as the adjustments are made. In addition to conventional navigation and manipulation tools, such as scaling, LUT, volume slicing, and others, our strategy permits efficient visualization of PET/CT volume rendering which can potentially aid in interpretation and diagnosis.

Reaction monitoring using hyperpolarized NMR with scaling of heteronuclear couplings by optimal tracking

Science.gov (United States)

Zhang, Guannan; Schilling, Franz; Glaser, Steffen J.; Hilty, Christian

2016-11-01

Off-resonance decoupling using the method of Scaling of Heteronuclear Couplings by Optimal Tracking (SHOT) enables determination of heteronuclear correlations of chemical shifts in single scan NMR spectra. Through modulation of J-coupling evolution by shaped radio frequency pulses, off resonance decoupling using SHOT pulses causes a user-defined dependence of the observed J-splitting, such as the splitting of 13C peaks, on the chemical shift offset of coupled nuclei, such as 1H. Because a decoupling experiment requires only a single scan, this method is suitable for characterizing on-going chemical reactions using hyperpolarization by dissolution dynamic nuclear polarization (D-DNP). We demonstrate the calculation of [13C, 1H] chemical shift correlations of the carbanionic active sites from hyperpolarized styrene polymerized using sodium naphthalene as an initiator. While off resonance decoupling by SHOT pulses does not enhance the resolution in the same way as a 2D NMR spectrum would, the ability to obtain the correlations in single scans makes this method ideal for determination of chemical shifts in on-going reactions on the second time scale. In addition, we present a novel SHOT pulse that allows to scale J-splittings 50% larger than the respective J-coupling constant. This feature can be used to enhance the resolution of the indirectly detected chemical shift and reduce peak overlap, as demonstrated in a model reaction between p-anisaldehyde and isobutylamine. For both pulses, the accuracy is evaluated under changing signal-to-noise ratios (SNR) of the peaks from reactants and reaction products, with an overall standard deviation of chemical shift differences compared to reference spectra of 0.02 ppm when measured on a 400 MHz NMR spectrometer. Notably, the appearance of decoupling side-bands, which scale with peak intensity, appears to be of secondary importance.

Volume and Tissue Composition Changes Measured with Dual-Energy X-Ray Absorptiometry in Melanoma-Related Limb Lymphedema

DEFF Research Database (Denmark)

Gjorup, Caroline A; Hendel, Helle W; Zerahn, Bo

2017-01-01

Abstracts Background: The aim of this cross-sectional study was to investigate the volume, fat mass, and lean mass in both upper and lower limbs measured with dual-energy X-ray absorptiometry (DXA) in melanoma patients with melanoma-related limb lymphedema. METHODS AND RESULTS: Four hundred thirty...... lymphedema was diagnosed on the basis of history and characteristic physical findings on the clinical examination. The inter-limb differences in volume, fat mass, and lean mass measured with DXA were categorized as none/mild, moderate, or severe according to reference values (taking handedness into account......, and the majority of lymphedemas were categorized as mild. The increase in the volume of limbs with lymphedema was primarily due to an increase in fat mass. CONCLUSION: There is a high prevalence of melanoma-related limb lymphedema. The increase in volume in the limb with lymphedema is primarily due to an increase...

The Dual Orlicz-Brunn-Minkowski Theory

OpenAIRE

Gardner, Richard J.; Hug, Daniel; Weil, Wolfgang; Ye, Deping

2014-01-01

This paper introduces the dual Orlicz-Brunn-Minkowski theory for star sets. A radial Orlicz addition of two or more star sets is proposed and a corresponding dual Orlicz-Brunn-Minkowski inequality is established. Based on a radial Orlicz linear combination of two star sets, a formula for the dual Orlicz mixed volume is derived and a corresponding dual Orlicz-Minkowski inequality proved. The inequalities proved yield as special cases the precise duals of the conjectured log-Brunn-Minkowski and...

Heteronuclear cross-polarization in multinuclear multidimensional NMR: Prospects for triple-resonance CP

Energy Technology Data Exchange (ETDEWEB)

Majumdar, A.; Zuiderweg, E.R.P. [Univ. of Michigan, Ann Arbor, MI (United States)

1994-12-01

Heteronuclear multiple-pulse-based Cross Polarization (HECP) between scalar coupled spins is gaining an important role in high-resolution multidimensional NMR of isotopically labeled biomolecules, especially in experiments involving net magnetization transfer. It has generally been observed that in these situations, the performance of HECP is superior to that of INEPT-based sequences. In particular, HECP-based three-dimensional HCCH spectroscopy is more efficient than the INEPT version of the same experiment. Differences in sensitivity have been intuitively attributed to relaxation effects and technical factors such as radiofrequency (rf) inhomogeneity We present theoretical analyses and computer simulations to probe the effects of these factors. Relaxation effects were treated phenomenologically; we found that relaxation differences are relatively small (up to 25%) between pulsed-free-precession (INEPT) and HECP-although always in favor of HECP. We explored the rf effects by employing a Gaussian distribution of rf amplitude over sample volume. We found that inhomogeneity effects significantly favor HECP over INEPT, especially under conditions of {open_quotes}matched {close_quotes} inhomogeneity in the two rf coils. The differences in favor of HECP indicate that an extension of HECP to triple resonance experiments (TRCP) in I -> S -> Q net transfers might yield better results relative to analogous INEPT-based net transfers. We theoretically analyze the possibilities of TRCP and find that transfer functions are critically dependent on the ratio J{sub IS}/J{sub SQ}. When J{sub IS} equals J{sub SQ}, we find that 100% transfer is possible for truly simultaneous TRCP and this transfer is obtained in a time 1.41 /J. The TRCP time requirement compares favorably with optimally concatenated INEPT-transfers, where net transfer I -> S -> Q is complete at 1.5 /J.

Dual Orlicz geominimal surface area

Directory of Open Access Journals (Sweden)

Tongyi Ma

2016-02-01

Full Text Available Abstract The L p $L_{p}$ -geominimal surface area was introduced by Lutwak in 1996, which extended the important concept of the geominimal surface area. Recently, Wang and Qi defined the p-dual geominimal surface area, which belongs to the dual Brunn-Minkowski theory. In this paper, based on the concept of the dual Orlicz mixed volume, we extend the dual geominimal surface area to the Orlicz version and give its properties. In addition, the isoperimetric inequality, a Blaschke-Santaló type inequality, and the monotonicity inequality for the dual Orlicz geominimal surface areas are established.

Evaluation of the anterior ethmoidal artery by 3D dual volume rotational digital subtraction angiography and native multidetector CT with multiplanar reformations. Initial findings.

Science.gov (United States)

Pandolfo, Ignazio; Vinci, Sergio; Salamone, Ignazio; Granata, Francesca; Mazziotti, Silvio

2007-06-01

Our purpose is to codify the anterior ethmoidal artery (AEA) course and its relationship with adjacent structures. Twenty patients with cerebrovascular disease underwent selective internal carotid dual volume angiography. Fusion of the vascular and bony images was obtained successively on a second console. MDCT of the cranium was performed in all patients. To identify the AEA course, multiplanar CT reformations were obtained. In all cases the entry-point of AEA and its course were identified by means of dual volume angiography. The information was confirmed by MDCT. In a second phase, we studied another 78 patients affected by inflammatory disease and polyposis only by means of MDCT, in order to confirm the previous data obtained by comparison between angiography and MDCT. In this second phase, 110/156 vessels were indirectly detected by means of visualization of the ethmoidal entry point. In the remaining cases, AEA was directly shown due to integrity of the thin ethmoidal bone lamellae or bony canal. Dual volume angiography is essential to identify the course of the AEA (standard of reference for the interpretation of CT). In patients with benign rhinosinusal pathology, where invasivity techniques are not justified, MPR reconstructions were of pivotal importance in the evaluation of the course of the artery with particular reference to its relationship with the frontal recess.

Holographic complexity and fidelity susceptibility as holographic information dual to different volumes in AdS

Directory of Open Access Journals (Sweden)

N.S. Mazhari

2017-03-01

Full Text Available The holographic complexity and fidelity susceptibility have been defined as new quantities dual to different volumes in AdS. In this paper, we will use these new proposals to calculate both of these quantities for a variety of interesting deformations of AdS. We obtain the holographic complexity and fidelity susceptibility for an AdS black hole, Janus solution, a solution with cylindrical symmetry, an inhomogeneous background and a hyperscaling violating background. It is observed that the holographic complexity depends on the size of the subsystem for all these solutions and the fidelity susceptibility does not have any such dependence.

Holographic complexity and fidelity susceptibility as holographic information dual to different volumes in AdS

Energy Technology Data Exchange (ETDEWEB)

Mazhari, N.S., E-mail: najmemazhari86@gmail.com [Eurasian International Center for Theoretical Physics and Department of General & Theoretical Physics, Eurasian National University, Astana 010008 (Kazakhstan); Momeni, Davood, E-mail: davoodmomeni78@gmail.com [Eurasian International Center for Theoretical Physics and Department of General & Theoretical Physics, Eurasian National University, Astana 010008 (Kazakhstan); Bahamonde, Sebastian, E-mail: sebastian.beltran.14@ucl.ac.uk [Department of Mathematics, University College London, Gower Street, London, WC1E 6BT (United Kingdom); Faizal, Mir, E-mail: mirfaizalmir@googlemail.com [Irving K. Barber School of Arts and Sciences, University of British Columbia - Okanagan, 3333 University Way, Kelowna, British Columbia, V1V 1V7 (Canada); Department of Physics and Astronomy, University of Lethbridge, Lethbridge, Alberta, T1K 3M4 (Canada); Myrzakulov, Ratbay, E-mail: rmyrzakulov@gmail.com [Eurasian International Center for Theoretical Physics and Department of General & Theoretical Physics, Eurasian National University, Astana 010008 (Kazakhstan)

2017-03-10

The holographic complexity and fidelity susceptibility have been defined as new quantities dual to different volumes in AdS. In this paper, we will use these new proposals to calculate both of these quantities for a variety of interesting deformations of AdS. We obtain the holographic complexity and fidelity susceptibility for an AdS black hole, Janus solution, a solution with cylindrical symmetry, an inhomogeneous background and a hyperscaling violating background. It is observed that the holographic complexity depends on the size of the subsystem for all these solutions and the fidelity susceptibility does not have any such dependence.

Dual-energy perfusion-CT of pancreatic adenocarcinoma

International Nuclear Information System (INIS)

Klauß, M.; Stiller, W.; Pahn, G.; Fritz, F.; Kieser, M.; Werner, J.; Kauczor, H.U.; Grenacher, L.

2013-01-01

Purpose: To evaluate the feasibility of dual-energy CT (DECT)-perfusion of pancreatic carcinomas for assessing the differences in perfusion, permeability and blood volume of healthy pancreatic tissue and histopathologically confirmed solid pancreatic carcinoma. Materials and methods: 24 patients with histologically proven pancreatic carcinoma were examined prospectively with a 64-slice dual source CT using a dynamic sequence of 34 dual-energy (DE) acquisitions every 1.5 s (80 ml of iodinated contrast material, 370 mg/ml, flow rate 5 ml/s). 80 kV p , 140 kV p , and weighted average (linearly blended M0.3) 120 kV p -equivalent dual-energy perfusion image data sets were evaluated with a body-perfusion CT tool (Body-PCT, Siemens Medical Solutions, Erlangen, Germany) for estimating perfusion, permeability, and blood volume values. Color-coded parameter maps were generated. Results: In all 24 patients dual-energy CT-perfusion was. All carcinomas could be identified in the color-coded perfusion maps. Calculated perfusion, permeability and blood volume values were significantly lower in pancreatic carcinomas compared to healthy pancreatic tissue. Weighted average 120 kV p -equivalent perfusion-, permeability- and blood volume-values determined from DE image data were 0.27 ± 0.04 min −1 vs. 0.91 ± 0.04 min −1 (p −1 vs. 0.67 ± 0.05 *0.5 min −1 (p = 0.06) and 0.49 ± 0.07 min −1 vs. 1.28 ± 0.11 min −1 (p p the standard deviations of the kV p 120 kV p -equivalent values were manifestly smaller. Conclusion: Dual-energy CT-perfusion of the pancreas is feasible. The use of DECT improves the accuracy of CT-perfusion of the pancreas by fully exploiting the advantages of enhanced iodine contrast at 80 kV p in combination with the noise reduction at 140 kV p . Therefore using dual-energy perfusion data could improve the delineation of pancreatic carcinomas

Observation of Resonant Effects in Ultracold Collisions between Heteronuclear Feshbach Molecules

Science.gov (United States)

Ye, Xin; Wang, Fudong; Zhu, Bing; Guo, Mingyang; Lu, Bo; Wang, Dajun

2016-05-01

Magnetic field dependent dimer-dimer collisional losses are studied with ultracold 23 Na87 Rb Feshbach molecules. By ramping the magnetic field across the 347.8 G inter-species Feshbach resonance and removing residual atoms with a magnetic field gradient, ~ 8000 pure NaRb Feshbach molecules with a temperature below 1 μK are produced. By holding the pure molecule sample in a crossed optical dipole trap and measuring the time-dependent loss curves under different magnetic fields near the Feshbach resonance, the dimer-dimer loss rates with respect to the atomic scattering length a are mapped out. We observe a resonant feature at around a = 600a0 and a rising tail at above a = 1600a0 . This behavior resembles previous theoretical works on homonuclear Feshbach molecule, where resonant effects between dimer-dimer collisions tied to tetramer bound states were predicted. Our work shows the possibility of exploring four-body physics within a heteronuclear system. We are supported by Hong Kong RGC General Research Fund no. CUHK403813.

Metamaterial Combining Electric- and Magnetic-Dipole-Based Configurations for Unique Dual-Band Signal Enhancement in Ultrahigh-Field Magnetic Resonance Imaging.

Science.gov (United States)

Schmidt, Rita; Webb, Andrew

2017-10-11

Magnetic resonance imaging and spectroscopy (MRI and MRS) are both widely used techniques in medical diagnostics and research. One of the major thrusts in recent years has been the introduction of ultrahigh-field magnets in order to boost the sensitivity. Several MRI studies have examined further potential improvements in sensitivity using metamaterials, focusing on single frequency applications. However, metamaterials have yet to reach a level that is practical for routine MRI use. In this work, we explore a new metamaterial implementation for MRI, a dual-nuclei resonant structure, which can be used for both proton and heteronuclear magnetic resonance. Our approach combines two configurations, one based on a set of electric dipoles for the low frequency band, and the second based on a set of magnetic dipoles for the high frequency band. We focus on the implementation of a dual-nuclei metamaterial for phosphorus and proton imaging and spectroscopy at an ultrahigh-field strength of 7 T. In vivo scans using this flexible and compact structure show that it locally enhances both the phosphorus and proton transmit and receive sensitivities.

Facial rejuvenation with fillers: The dual plane technique

Directory of Open Access Journals (Sweden)

Giovanni Salti

2015-01-01

Full Text Available Background: Facial aging is characterized by skin changes, sagging and volume loss. Volume is frequently addressed with reabsorbable fillers like hyaluronic acid gels. Materials and Methods: From an anatomical point of view, the deep and superficial fat compartments evolve differently with aging in a rather predictable manner. Volume can therefore be restored following a technique based on restoring first the deep volumes and there after the superficial volumes. We called this strategy "dual plane". A series of 147 consecutive patients have been treated with fillers using the dual plane technique in the last five years. Results: An average of 4.25 session per patient has been carried out for a total of 625 treatment sessions. The average total amount of products used has been 12 ml per patient with an average amount per session of 3.75 ml. We had few and limited adverse events with this technique. Conclusion: The dual plane technique is an injection technique based on anatomical logics. Different types of products can be used according to the plane of injection and their rheology in order to obtain a natural result and few side effects.

Xenon ventilation CT using dual-source and dual-energy technique in children with bronchiolitis obliterans: correlation of xenon and CT density values with pulmonary function test results

International Nuclear Information System (INIS)

Goo, Hyun Woo; Yang, Dong Hyun; Seo, Joon Beom; Chae, Eun Jin; Lee, Jeongjin; Hong, Soo-Jong; Yu, Jinho; Kim, Byoung-Ju; Krauss, Bernhard

2010-01-01

Xenon ventilation CT using dual-source and dual-energy technique is a recently introduced, promising functional lung imaging method. To expand its clinical applications evidence of additional diagnostic value of xenon ventilation CT over conventional chest CT is required. To evaluate the usefulness of xenon ventilation CT using dual-source and dual-energy technique in children with bronchiolitis obliterans (BO). Seventeen children (age 7-18 years; 11 boys) with BO underwent xenon ventilation CT using dual-source and dual-energy technique. Xenon and CT density values were measured in normal and hyperlucent lung regions on CT and were compared between the two regions. Volumes of hyperlucent regions and ventilation defects were calculated with thresholds determined by visual and histogram-based analysis. Indexed volumes of hyperlucent lung regions and ventilation defects were correlated with pulmonary function test results. Effective doses of xenon CT were calculated. Xenon (14.6 ± 6.4 HU vs 26.1 ± 6.5 HU; P 25-75 , (γ = -0.68-0.88, P ≤ 0.002). Volume percentages of xenon ventilation defects (35.0 ± 16.4%)] were not significantly different from those of hyperlucent lung regions (38.2 ± 18.6%). However, mismatches between the volume percentages were variable up to 21.4-33.3%. Mean effective dose of xenon CT was 1.9 ± 0.5 mSv. In addition to high-resolution anatomic information, xenon ventilation CT using dual-source and dual-energy technique demonstrates impaired regional ventilation and its heterogeneity accurately in children with BO without additional radiation exposure. (orig.)

General volumes in the Orlicz-Brunn-Minkowski theory and a related Minkowski Problem I

OpenAIRE

Gardner, Richard J.; Hug, Daniel; Weil, Wolfgang; Xing, Sudan; Ye, Deping

2018-01-01

The general volume of a star body, a notion that includes the usual volume, the $q$th dual volumes, and many previous types of dual mixed volumes, is introduced. A corresponding new general dual Orlicz curvature measure is defined that specializes to the $(p,q)$-dual curvature measures introduced recently by Lutwak, Yang, and Zhang. General variational formulas are established for the general volume of two types of Orlicz linear combinations. One of these is applied to the Minkowski problem f...

Numerical Study for a Large Volume Droplet on the Dual-rough Surface: Apparent Contact Angle, Contact Angle Hysteresis and Transition Barrier.

Science.gov (United States)

Dong, Jian; Jin, Yanli; Dong, He; Liu, Jiawei; Ye, Senbin

2018-06-14

The profile, apparent contact angle (ACA), contact angle hysteresis (CAH) and wetting state transmission energy barrier (WSTEB) are important static and dynamic properties of a large volume droplet on the hierarchical surface. Understanding them can provide us with important insights to functional surfaces and promote the application in corresponding areas. In this paper, we established three theoretical models (Model 1, Model 2 and Model 3) and corresponding numerical methods, which were obtained by the free energy minimization and the nonlinear optimization algorithm, to predict the profile, ACA, CAH and WSTEB of a large volume droplet on the horizontal regular dual-rough surface. In consideration of the gravity, the energy barrier on the contact circle, the dual heterogenous structures and their roughness on the surface, the models are more universal and accurate than previous models. It showed that the predictions of the models were in good agreement with the results from the experiment or literature. The models are promising to become novel design approaches of functional surfaces, which are frequently applied in microfluidic chips, water self-catchment system and dropwise condensation heat transfer system.

Large volume serial section tomography by Xe Plasma FIB dual beam microscopy.

Science.gov (United States)

Burnett, T L; Kelley, R; Winiarski, B; Contreras, L; Daly, M; Gholinia, A; Burke, M G; Withers, P J

2016-02-01

Ga(+) Focused Ion Beam-Scanning Electron Microscopes (FIB-SEM) have revolutionised the level of microstructural information that can be recovered in 3D by block face serial section tomography (SST), as well as enabling the site-specific removal of smaller regions for subsequent transmission electron microscope (TEM) examination. However, Ga(+) FIB material removal rates limit the volumes and depths that can be probed to dimensions in the tens of microns range. Emerging Xe(+) Plasma Focused Ion Beam-Scanning Electron Microscope (PFIB-SEM) systems promise faster removal rates. Here we examine the potential of the method for large volume serial section tomography as applied to bainitic steel and WC-Co hard metals. Our studies demonstrate that with careful control of milling parameters precise automated serial sectioning can be achieved with low levels of milling artefacts at removal rates some 60× faster. Volumes that are hundreds of microns in dimension have been collected using fully automated SST routines in feasible timescales (<24h) showing good grain orientation contrast and capturing microstructural features at the tens of nanometres to the tens of microns scale. Accompanying electron back scattered diffraction (EBSD) maps show high indexing rates suggesting low levels of surface damage. Further, under high current Ga(+) FIB milling WC-Co is prone to amorphisation of WC surface layers and phase transformation of the Co phase, neither of which have been observed at PFIB currents as high as 60nA at 30kV. Xe(+) PFIB dual beam microscopes promise to radically extend our capability for 3D tomography, 3D EDX, 3D EBSD as well as correlative tomography. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Self-dual nonsupersymmetric Type II String Compactifications

International Nuclear Information System (INIS)

Kachru, Shamit; Silverstein, Eva

1998-01-01

It has recently been proposed that certain nonsupersymmetric type II orbifolds have vanishing perturbative contributions to the cosmological constant. We show that techniques of Sen and Vafa allow one to construct dual type II descriptions of these models (some of which have no weakly coupled heterotic dual). The dual type II models are given by the same orbifolds with the string coupling S and a T 2 volume T exchanged. This allows us to argue that in various strongly coupled limits of the original type II models, there are weakly coupled duals which exhibit the same perturbative cancellations as the original models

Photochemical deposition of NiCoO x thin films from Ni/Co heteronuclear triketonate complexes

International Nuclear Information System (INIS)

Buono-Core, G.E.; Tejos, M.; Cabello, G.; Guzman, N.; Hill, R.H.

2006-01-01

UV light irradiation of thin films of a polyketonate Ni/Co heteronuclear complex, NiCo(DBA) 2 [DBA, dibenzoylacetone)], spin coated on Si(1 0 0) substrates produced NiCoO x mixed oxides as amorphous films. On annealing at 600 deg. C under air, the mixed oxide film decomposed to NiO and CoO as indicated by XRD measurements. The morphology of the as-deposited films was examined by AFM analysis showing a smooth surface with low rms roughness values. The ratio of Ni/Co (1.08) present in the film reflects the stoichiometry in the starting compound within the experimental error, as shown by XPS analysis. The large amount of carbon (20.8%) detected on the surface of the film may be due to the presence of phenyl rings in the precursor complex

Dual-mixed finite elements for the three-field Stokes model as a finite volume method on staggered grids

KAUST Repository

Kou, Jisheng

2017-06-09

In this paper, a new three-field weak formulation for Stokes problems is developed, and from this, a dual-mixed finite element method is proposed on a rectangular mesh. In the proposed mixed methods, the components of stress tensor are approximated by piecewise constant functions or Q1 functions, while the velocity and pressure are discretized by the lowest-order Raviart-Thomas element and the piecewise constant functions, respectively. Using quadrature rules, we demonstrate that this scheme can be reduced into a finite volume method on staggered grid, which is extensively used in computational fluid mechanics and engineering.

High Field In Vivo 13C Magnetic Resonance Spectroscopy of Brain by Random Radiofrequency Heteronuclear Decoupling and Data Sampling

Science.gov (United States)

Li, Ningzhi; Li, Shizhe; Shen, Jun

2017-06-01

In vivo 13C magnetic resonance spectroscopy (MRS) is a unique and effective tool for studying dynamic human brain metabolism and the cycling of neurotransmitters. One of the major technical challenges for in vivo 13C-MRS is the high radio frequency (RF) power necessary for heteronuclear decoupling. In the common practice of in vivo 13C-MRS, alkanyl carbons are detected in the spectra range of 10-65ppm. The amplitude of decoupling pulses has to be significantly greater than the large one-bond 1H-13C scalar coupling (1JCH=125-145 Hz). Two main proton decoupling methods have been developed: broadband stochastic decoupling and coherent composite or adiabatic pulse decoupling (e.g., WALTZ); the latter is widely used because of its efficiency and superb performance under inhomogeneous B1 field. Because the RF power required for proton decoupling increases quadratically with field strength, in vivo 13C-MRS using coherent decoupling is often limited to low magnetic fields (protons via weak long-range 1H-13C scalar couplings, which can be decoupled using low RF power broadband stochastic decoupling. Recently, the carboxylic/amide 13C-MRS technique using low power random RF heteronuclear decoupling was safely applied to human brain studies at 7T. Here, we review the two major decoupling methods and the carboxylic/amide 13C-MRS with low power decoupling strategy. Further decreases in RF power deposition by frequency-domain windowing and time-domain random under-sampling are also discussed. Low RF power decoupling opens the possibility of performing in vivo 13C experiments of human brain at very high magnetic fields (such as 11.7T), where signal-to-noise ratio as well as spatial and temporal spectral resolution are more favorable than lower fields.

Contrast volume reduction using third generation dual source computed tomography for the evaluation of patients prior to transcatheter aortic valve implantation

Energy Technology Data Exchange (ETDEWEB)

Bittner, Daniel O. [University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuernberg (FAU), Department of Internal Medicine 2 (Cardiology), Erlangen (Germany); Harvard Medical School, Cardiac MR PET CT Program, Massachusetts General Hospital, Boston, MA (United States); Arnold, Martin; Klinghammer, Lutz; Schuhbaeck, Annika; Hell, Michaela M.; Muschiol, Gerd; Gauss, Soeren; Achenbach, Stephan; Marwan, Mohamed [University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuernberg (FAU), Department of Internal Medicine 2 (Cardiology), Erlangen (Germany); Lell, Michael; Uder, Michael [University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuernberg (FAU), Department of Radiology, Erlangen (Germany); Hoffmann, Udo [Harvard Medical School, Cardiac MR PET CT Program, Massachusetts General Hospital, Boston, MA (United States)

2016-12-15

Chronic renal failure is common in patients referred for transcatheter aortic valve implantation (TAVI). CT angiography is recommended and provides crucial information prior to TAVI. We evaluated the feasibility of a reduced contrast volume protocol for pre-procedural CT imaging. Forty consecutive patients were examined with prospectively ECG-triggered high-pitch spiral acquisition using a novel third-generation dual-source CT system; 38 ml contrast agent was used. Image quality was graded on a visual scale (1-4). Contrast attenuation was measured at the level of the aortic root and at the iliac bifurcation. Mean patient age was 82 ± 6 years (23 males; 58 %). Mean attenuation/average image quality was 285 ± 60 HU/1.5 at the aortic annulus compared to 289 ± 74 HU/1.8 at the iliac bifurcation (p = 0.77/p = 0.29). Mean estimated effective radiation dose was 2.9 ± 0.3 mSv. A repeat acquisition was necessary in one patient due to image quality. Out of the 35 patients who underwent TAVI, 31 (89 %) patients had no or mild aortic regurgitation. Thirty-two (91 %) patients were discharged successfully. Pre-procedural CTA with a total of 38 ml contrast volume is feasible and clinically useful, using third-generation dual-source CT, allowing comprehensive imaging for procedural success. (orig.)

A dual resolution measurement based Monte Carlo simulation technique for detailed dose analysis of small volume organs in the skull base region

International Nuclear Information System (INIS)

Yeh, Chi-Yuan; Tung, Chuan-Jung; Chao, Tsi-Chain; Lin, Mu-Han; Lee, Chung-Chi

2014-01-01

The purpose of this study was to examine dose distribution of a skull base tumor and surrounding critical structures in response to high dose intensity-modulated radiosurgery (IMRS) with Monte Carlo (MC) simulation using a dual resolution sandwich phantom. The measurement-based Monte Carlo (MBMC) method (Lin et al., 2009) was adopted for the study. The major components of the MBMC technique involve (1) the BEAMnrc code for beam transport through the treatment head of a Varian 21EX linear accelerator, (2) the DOSXYZnrc code for patient dose simulation and (3) an EPID-measured efficiency map which describes non-uniform fluence distribution of the IMRS treatment beam. For the simulated case, five isocentric 6 MV photon beams were designed to deliver a total dose of 1200 cGy in two fractions to the skull base tumor. A sandwich phantom for the MBMC simulation was created based on the patient's CT scan of a skull base tumor [gross tumor volume (GTV)=8.4 cm 3 ] near the right 8th cranial nerve. The phantom, consisted of a 1.2-cm thick skull base region, had a voxel resolution of 0.05×0.05×0.1 cm 3 and was sandwiched in between 0.05×0.05×0.3 cm 3 slices of a head phantom. A coarser 0.2×0.2×0.3 cm 3 single resolution (SR) phantom was also created for comparison with the sandwich phantom. A particle history of 3×10 8 for each beam was used for simulations of both the SR and the sandwich phantoms to achieve a statistical uncertainty of <2%. Our study showed that the planning target volume (PTV) receiving at least 95% of the prescribed dose (VPTV95) was 96.9%, 96.7% and 99.9% for the TPS, SR, and sandwich phantom, respectively. The maximum and mean doses to large organs such as the PTV, brain stem, and parotid gland for the TPS, SR and sandwich MC simulations did not show any significant difference; however, significant dose differences were observed for very small structures like the right 8th cranial nerve, right cochlea, right malleus and right semicircular

Added value of lung perfused blood volume images using dual-energy CT for assessment of acute pulmonary embolism

International Nuclear Information System (INIS)

Okada, Munemasa; Kunihiro, Yoshie; Nakashima, Yoshiteru; Nomura, Takafumi; Kudomi, Shohei; Yonezawa, Teppei; Suga, Kazuyoshi; Matsunaga, Naofumi

2015-01-01

Purpose: To investigate the added value of lung perfused blood volume (LPBV) using dual-energy CT for the evaluation of intrapulmonary clot (IPC) in patients suspected of having acute pulmonary embolism (PE). Materials and methods: Institutional review board approval was obtained for this retrospective study. Eighty-three patients suspected of having PE who underwent CT pulmonary angiography (CTPA) using a dual-energy technique were enrolled in this study. Two radiologists who were blinded retrospectively and independently reviewed CTPA images alone and the combined images with color-coded LPBV over a 4-week interval, and two separate sessions were performed with a one-month interval. Inter- and intraobserver variability and diagnostic accuracy were evaluated for each reviewer with receiver operating characteristic (ROC) curve analysis. Results: Values for inter- and intraobserver agreement, respectively, were better for CTPA combined with LPBV (ICC = 0.847 and 0.937) than CTPA alone (ICC = 0.748 and 0.861). For both readers, diagnostic accuracy (area under the ROC curve [A z ]) were also superior, when CTPA alone (A z = 0.888 [reader 1] and 0.912 [reader 2]) was compared with that after the combination with LPBV images (A z = 0.966 [reader 1] and 0.959 [reader 2]) (p < 0.001). However, A z values of both images might not have significant difference in statistics, because A z value of CTPA alone was high and 95% confidence intervals overlapped in both images. Conclusion: Addition of dual-energy perfusion CT to CTPA improves detection of peripheral IPCs with better interobserver agreement

Hydrothermal liquefaction oil and hydrotreated product from pine feedstock characterized by heteronuclear two-dimensional NMR spectroscopy and FT-ICR mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Sudasinghe, Nilusha; Cort, John R.; Hallen, Richard T.; Olarte, Mariefel V.; Schmidt, Andrew J.; Schaub, Tanner

2014-12-01

Hydrothermal liquefaction (HTL) crude oil and hydrotreated product from pine tree farm waste (forest product residual, FPR) have been analyzed by direct infusion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) in both positive- and negative-ionization modes and high-resolution twodimensional heteronuclear 1H-13C NMR spectroscopy. FT-ICR MS resolves thousands of compounds in complex oils and provides unparalleled compositional details for individual molecules for identification of compound class (heteroatom content), type (number of rings plus double bonds to carbon or double bond equivalents (DBE) and carbon number (degree of alkylation). Heteronuclear 1H-13C NMR spectroscopy provides one-bond and multiple-bond correlations between pairs of 1H and 13C chemical shifts that are characteristic of different organic functional groups. Taken together this information provides a picture of the chemical composition of these oils. Pyrolysis crude oil product from pine wood was characterized for comparison. Generally, pyrolysis oil is comprised of a more diverse distribution of heteroatom classes with higher oxygen number relative to HTL oil as shown by both positive- and negative-ion ESI FT-ICR MS. A total of 300 N1, 594 O1 and 267 O2 compounds were observed as products of hydrotreatment. The relative abundance of N1O1, N1O2, N1O3, N2, N2O1, N2O2 and O3 compounds are reduced to different degrees after hydrotreatment and other higher heteroatom containing species (O4-O10, N1O4, N1O5 and N2O3) are completely removed by hydrotreatment.

Recent progress in heteronuclear long-range NMR of complex carbohydrates: 3D H2BC and clean HMBC

DEFF Research Database (Denmark)

Meier, Sebastian; Petersen, Bent O.; Duus, Jens Øllgaard

2009-01-01

carbohydrates whose structure has been determined by NMR, not least due to the enhanced resolution offered by the third dimension in 3D H2BC and the improved spectral quality due to artifact suppression in clean HMBC. Hence these new experiments set the scene to take advantage of the sensitivity boost achieved...... by the latest generation of cold probes for NMR structure determination of even larger and more complex carbohydrates in solution.......The new NMR experiments 3D H2BC and clean HMBC are explored for challenging applications to a complex carbohydrate at natural abundance of 13C. The 3D H2BC experiment is crucial for sequential assignment as it yields heteronuclear one- and two-bond together with COSY correlations for the 1H spins...

Synthesis and investigation of new heteronuclear [Zn-La] coordination compounds based on unsaturated lanthanum complex with N,N'-tetraethyl-N''-trichloacetylphosphortriamide

International Nuclear Information System (INIS)

Amyirkhanov, O.V.; Sliva, T.Yu.; Moroz, O.V.; Trush, Je.A.; Frits'kij, Yi.O.

2011-01-01

New heteronuclear [Zn-La] coordination compounds, perspective luminescent materials, with general formulas [Zn(Ve)La(X) 2 (Ac)] ({Zn-La;Ve;X}) and [Zn(Vp)La(X) 2 (Ac)] ({Zn-La;Vp;X}) have been synthesized HX=CCl 3 C(O)NHP(O)[N(C 2 H 5 ) 2 ] 2 - N,N'-tetraethyl-N''-trichloracetylphosphortriamide, H 2 Ve and H 2 Vp are products of the condensation of 1,2-diaminoethane and 1,3-diaminopropane with o-vanillin, respectively). The composition of [Zn-La] complexes has been determined, and the coordination mode of a phosphorylated ligand has been suggested by element analysis, IR- and 1 H, 31 P NMR-spectroscopy.

Automatic intensity-based 3D-to-2D registration of CT volume and dual-energy digital radiography for the detection of cardiac calcification

Science.gov (United States)

Chen, Xiang; Gilkeson, Robert; Fei, Baowei

2007-03-01

We are investigating three-dimensional (3D) to two-dimensional (2D) registration methods for computed tomography (CT) and dual-energy digital radiography (DR) for the detection of coronary artery calcification. CT is an established tool for the diagnosis of coronary artery diseases (CADs). Dual-energy digital radiography could be a cost-effective alternative for screening coronary artery calcification. In order to utilize CT as the "gold standard" to evaluate the ability of DR images for the detection and localization of calcium, we developed an automatic intensity-based 3D-to-2D registration method for 3D CT volumes and 2D DR images. To generate digital rendering radiographs (DRR) from the CT volumes, we developed three projection methods, i.e. Gaussian-weighted projection, threshold-based projection, and average-based projection. We tested normalized cross correlation (NCC) and normalized mutual information (NMI) as similarity measurement. We used the Downhill Simplex method as the search strategy. Simulated projection images from CT were fused with the corresponding DR images to evaluate the localization of cardiac calcification. The registration method was evaluated by digital phantoms, physical phantoms, and clinical data sets. The results from the digital phantoms show that the success rate is 100% with mean errors of less 0.8 mm and 0.2 degree for both NCC and NMI. The registration accuracy of the physical phantoms is 0.34 +/- 0.27 mm. Color overlay and 3D visualization of the clinical data show that the two images are registered well. This is consistent with the improvement of the NMI values from 0.20 +/- 0.03 to 0.25 +/- 0.03 after registration. The automatic 3D-to-2D registration method is accurate and robust and may provide a useful tool to evaluate the dual-energy DR images for the detection of coronary artery calcification.

Dual giant gravitons in Sasaki-Einstein backgrounds

International Nuclear Information System (INIS)

Martelli, Dario; Sparks, James

2006-01-01

We study the dynamics of a BPS D3-brane wrapped on a three-sphere in AdS 5 xL, a so-called dual giant graviton, where L is a Sasakian five-manifold. The phase space of these configurations is the symplectic cone X over L, and geometric quantisation naturally produces a Hilbert space of L 2 -normalisable holomorphic functions on X, whose states are dual to scalar chiral BPS operators in the dual superconformal field theory. We define classical and quantum partition functions and relate them to earlier mathematical constructions by the authors and S.-T. Yau, [D. Martelli, J. Sparks, S.-T. Yau, Sasaki-Einstein manifolds and volume minimisation, hep-th/0603021]. In particular, a Sasaki-Einstein metric then minimises an entropy function associated with the D3-brane. Finally, we introduce a grand canonical partition function that counts multiple dual giant gravitons. This is related simply to the index-character of the above reference, and provides a method for counting multi-trace scalar BPS operators in the dual superconformal field theory

Atom-dimer scattering in a heteronuclear mixture with a finite intraspecies scattering length

Science.gov (United States)

Gao, Chao; Zhang, Peng

2018-04-01

We study the three-body problem of two ultracold identical bosonic atoms (denoted by B ) and one extra atom (denoted by X ), where the scattering length aB X between each bosonic atom and atom X is resonantly large and positive. We calculate the scattering length aad between one bosonic atom and the shallow dimer formed by the other bosonic atom and atom X , and investigate the effect induced by the interaction between the two bosonic atoms. We find that even if this interaction is weak (i.e., the corresponding scattering length aB B is of the same order of the van der Waals length rvdW or even smaller), it can still induce a significant effect for the atom-dimer scattering length aad. Explicitly, an atom-dimer scattering resonance can always occur when the value of aB B varies in the region with | aB B|≲ rvdW . As a result, both the sign and the absolute value of aad, as well as the behavior of the aad-aB X function, depends sensitively on the exact value of aB B. Our results show that, for a good quantitative theory, the intraspecies interaction is required to be taken into account for this heteronuclear system, even if this interaction is weak.

Dual-modality and dual-energy gamma ray densitometry of petroleum products using an artificial neural network

International Nuclear Information System (INIS)

Roshani, G.H.; Feghhi, S.A.H.; Setayeshi, S.

2015-01-01

The prediction of volume fractions in order to measure the multiphase flow rate is a very important issue and is the key parameter of multi-phase flow meters (MPFMs). Currently, the gamma ray attenuation technique is known as one of the most precise methods for obtaining volume fractions. The gamma ray attenuation technique is based on the mass attenuation coefficient, which is sensitive to density changes; density is sensitive in turn to temperature and pressure fluctuations. Therefore, MPFM efficiency depends strongly on environmental conditions. The conventional solution to this problem is the periodical recalibration of MPFMs, which is a demanding task. In this study, a method based on dual-modality densitometry and artificial intelligence (AI) is presented, which offers the advantage of the measurement of the oil–gas–water volume fractions independent of density changes. For this purpose, several experiments were carried out and used to validate simulated dual modality densitometry results. The reference density point was established at a temperature of 20 °C and pressure of 1 bar. To cover the full range of likely density fluctuations, four additional density sets were defined (at changes of ±4% and ±8% from the reference point). An annular regime with different percentages of oil, gas and water at different densities was simulated. Four features were extracted from the transmission and scattered detectors and were applied to the artificial neural network (ANN) as inputs. The input parameters included the "2"4"1Am full energy peak, "1"3"7Cs Compton edge, "1"3"7Cs full energy peak and total scattered count, and the outputs were the oil and air percentages. A multi-layer perceptron (MLP) neural network was used to predict the volume fraction independent of the oil and water density changes. The obtained results show that the proposed ANN model achieved good agreement with the real data, with an estimated root mean square error (RMSE) of less than 3

DUAL TIMELIKE NORMAL AND DUAL TIMELIKE SPHERICAL CURVES IN DUAL MINKOWSKI SPACE

OpenAIRE

ÖNDER, Mehmet

2009-01-01

Abstract: In this paper, we give characterizations of dual timelike normal and dual timelike spherical curves in the dual Minkowski 3-space and we show that every dual timelike normal curve is also a dual timelike spherical curve. Keywords: Normal curves, Dual Minkowski 3-Space, Dual Timelike curves. Mathematics Subject Classifications (2000): 53C50, 53C40. DUAL MINKOWSKI UZAYINDA DUAL TIMELIKE NORMAL VE DUAL TIMELIKE KÜRESEL EĞRİLER Özet: Bu çalışmada, dual Minkowski 3-...

Dual energy CT pulmonary blood volume assessment in acute pulmonary embolism - correlation with D-dimer level, right heart strain and clinical outcome

International Nuclear Information System (INIS)

Bauer, Ralf W.; Frellesen, Claudia; Schell, Boris; Lehnert, Thomas; Jacobi, Volkmar; Vogl, Thomas J.; Kerl, J.M.; Renker, Matthias; Ackermann, Hanns; Schoepf, U.J.

2011-01-01

To investigate the role of perfusion defect (PD) size on dual energy CT pulmonary blood volume assessment as predictor of right heart strain and patient outcome and its correlation with d-dimer levels in acute pulmonary embolism (PE). 53 patients with acute PE who underwent DECT pulmonary angiography were retrospectively analyzed. Pulmonary PD size caused by PE was measured on DE iodine maps and quantified absolutely (VolPD) and relatively to the total lung volume (RelPD). Signs of right heart strain (RHS) on CT were determined. Information on d-dimer levels and readmission for recurrent onset of PE and death was collected. D-dimer level was mildly (r = 0.43-0.47) correlated with PD size. Patients with RHS had significantly higher VolPD (215 vs. 73 ml) and RelPD (9.9 vs. 2.9%) than patients without RHS (p 5% RelPD, while no such events were found for patients with <5% RelPD. Pulmonary blood volume on DECT in acute PE correlates with RHS and appears to be a predictor of patient outcome in this pilot study. (orig.)

Dual-ROI radionuclide ventriculography

International Nuclear Information System (INIS)

Standke, R.; Hoer, G.; Kanemoto, N.; Maul, F.D.

1981-01-01

Accurate determination of the left ventricular activity function is the precondition for a quantitative analysis of the ventricular volume function. During the volume reduction period, extra-myocardial tissue penetrates into the ROI of the late diastole. This curve-distorting activity cannot be eliminated by a single-ROI technique. Of the multiple-ROI techniques, the dual-ROI method is the least complex and tedions and involves the least methodological error. At the time of maximum volume change rates, the curve may be distorted if the late diastolic ROI is inaccurately defined. A method is described which uses only the counting rate over the late diastolic ROI and corrects it only on the basis of the counting rate of the late systolic ROI. The time parameters remain uninfluenced by this correction method while the volumetric parameters are corrected. (orig./APR) [de

Formability of high-alloy dual-phase Cr-Ni steels

International Nuclear Information System (INIS)

Elfmark, J.

2004-01-01

The formability of dual-phase high-alloy Cr-Ni steel within the temperature range from 900 to 1250 C was studied using laboratory tensile and torsion tests. The dual-phase steels on 24% Cr basis are characterized by poor hot formability due to very low stable deformation values and slow recrystallization. Mathematical description of deformation stability exhaustion was derived, as well as a model of formability control based on analysis of the gradual diffuse deformation stability from the stability limit to the moment when the deformation starts to concentrate in a small volume of the test piece. Rolling simulation of dual-phase steel strip was used as an example demonstrating the draught scheme optimization technique which avoids the danger of crack occurrence during the rolling of dual-phase steel strip. (orig.)

An improved synthesis of α-13C glycine and heteronuclear NMR studies of its incorporation into thioredoxin

International Nuclear Information System (INIS)

Wishart, D.S.; Sykes, B.D.; Richards, F.M.

1992-01-01

We present an improved method to easily prepare gram quantities of α- 13 C glycine beginning from K 13 CN. The four step synthesis involves the production of an N, N-diphenyl-cyanoformamidine intermediate through the coupling of cyanide to N, N-diphenylcarbodiimide. Subsequent reduction by LiAlH 4 and hydrolysis of the resulting amidine produces fully enriched α- 13 C labelled glycine with a 45-50% yield. This relatively fast and simple synthesis uses only commonly available compounds and requires no special equipment, making the process easy to perform in any well equipped biochemistry laboratory. We further demonstrate that the product may be used, without extensive purification, to specifically label bacterially expressed proteins (E. coli thioredoxin) through standard biosynthetic procedures. We also show that the 13 C glycine-labelled protein may be readily analyzed using commonly available heteronuclear NMR techniques. Complete assignments for all 9 glycines of native E. coli thoredoxin are presented. (Author)

Simulation of flow in dual-scale porous media

Science.gov (United States)

Tan, Hua

Liquid composite molding (LCM) is one of the most effective processes for manufacturing near net-shaped parts from fiber-reinforced polymer composites. The quality of LCM products and the efficiency of the process depend strongly on the wetting of fiber preforms during the mold-filling stage of LCM. Mold-filling simulation is a very effective approach to optimize the LCM process and mold design. Recent studies have shown that the flow modeling for the single-scale fiber preforms (made from random mats) has difficulties in accurately predicting the wetting in the dual-scale fiber preforms (made from woven and stitched fabrics); the latter are characterized by the presence of unsaturated flow created due to two distinct length-scales of pores (i.e., large pores outside the tows and small pores inside the tows) in the same media. In this study, we first develop a method to evaluate the accuracy of the permeability-measuring devices for LCM, and conduct a series of 1-D mold-filling experiments for different dual-scale fabrics. The volume averaging method is then applied to derive the averaged governing equations for modeling the macroscopic flow through the dual-scale fabrics. The two sets of governing equations are coupled with each other through the sink terms representing the absorptions of mass, energy, and species (degree of resin cure) from the global flow by the local fiber tows. The finite element method (FEM) coupled with the control volume method, also known as the finite element/control volume (FE/CV) method, is employed to solve the governing equations and track the moving boundary signifying the moving liquid-front. The numerical computations are conducted with the help of an in-house developed computer program called PORE-FLOW(c). We develop the flux-corrected transport (FCT) based FEM to stabilize the convection-dominated energy and species equations. A fast methodology is proposed to simulate the dual-scale flow under isothermal conditions, where flow

Microstructure Optimization of Dual-Phase Steels Using a Representative Volume Element and a Response Surface Method: Parametric Study

Science.gov (United States)

Belgasam, Tarek M.; Zbib, Hussein M.

2017-12-01

Dual-phase (DP) steels have received widespread attention for their low density and high strength. This low density is of value to the automotive industry for the weight reduction it offers and the attendant fuel savings and emission reductions. Recent studies on developing DP steels showed that the combination of strength/ductility could be significantly improved when changing the volume fraction and grain size of phases in the microstructure depending on microstructure properties. Consequently, DP steel manufacturers are interested in predicting microstructure properties and in optimizing microstructure design. In this work, a microstructure-based approach using representative volume elements (RVEs) was developed. The approach examined the flow behavior of DP steels using virtual tension tests with an RVE to identify specific mechanical properties. Microstructures with varied martensite and ferrite grain sizes, martensite volume fractions, carbon content, and morphologies were studied in 3D RVE approaches. The effect of these microstructure parameters on a combination of strength/ductility of DP steels was examined numerically using the finite element method by implementing a dislocation density-based elastic-plastic constitutive model, and a Response surface methodology to determine the optimum conditions for a required combination of strength/ductility. The results from the numerical simulations are compared with experimental results found in the literature. The developed methodology proves to be a powerful tool for studying the effect and interaction of key microstructural parameters on strength and ductility and thus can be used to identify optimum microstructural conditions.

The Prediction of the Mechanical Properties for Dual-Phase High Strength Steel Grades Based on Microstructure Characteristics

Directory of Open Access Journals (Sweden)

Emil Evin

2018-04-01

Full Text Available The decrease of emissions from vehicle operation is connected mainly to the reduction of the car’s body weight. The high strength and good formability of the dual phase steel grades predetermine these to be used in the structural parts of the car’s body safety zones. The plastic properties of dual phase steel grades are determined by the ferrite matrix while the strength properties are improved by the volume and distribution of martensite. The aim of this paper is to describe the relationship between the mechanical properties and the parameters of structure and substructure. The heat treatment of low carbon steel X60, low alloyed steel S460MC, and dual phase steel DP600 allowed for them to reach states with a wide range of volume fractions of secondary phases and grain size. The mechanical properties were identified by a tensile test, volume fraction of secondary phases, and grain size were measured by image analysis. It was found that by increasing the annealing temperature, the volume fraction of the secondary phase increased, and the ferrite grains were refined. Regression analysis was used to find out the equations for predicting mechanical properties based on the volume fraction of the secondary phase and grain size, following the annealing temperature. The hardening mechanism of the dual phase steel grades for the states they reached was described by the relationship between the strain-hardening exponent and the density of dislocations. This allows for the designing of dual phase steel grades that are “tailored” to the needs of the automotive industry customers.

Hole-expansion formability of dual-phase steels using representative volume element approach with boundary-smoothing technique

International Nuclear Information System (INIS)

Kim, Ji Hoon; Lee, M.G.; Kim, D.; Matlock, D.K.; Wagoner, R.H.

2010-01-01

Research highlights: → Robust microstructure-based FE mesh generation technique was developed. → Local deformation behavior near phase boundaries could be quantitatively understood. → Macroscopic failure could be connected to microscopic deformation behavior of multi-phase steel. - Abstract: A qualitative analysis was carried out on the formability of dual-phase (DP) steels by introducing a realistic microstructure-based finite element approach. The present microstructure-based model was constructed using a mesh generation process with a boundary-smoothing algorithm after proper image processing. The developed model was applied to hole-expansion formability tests for DP steel sheets having different volume fractions and morphological features. On the basis of the microstructural inhomogeneity observed in the scanning electron micrographs of the DP steel sheets, it was inferred that the localized plastic deformation in the ferritic phase might be closely related to the macroscopic formability of DP steel. The experimentally observed difference between the hole-expansion formability of two different microstructures was reasonably explained by using the present finite element model.

The Explicit Determinations Of Dual Plane Curves And Dual Helices In Terms Of Its Dual Curvature And Dual Torsion

OpenAIRE

Lee Jae Won; Choi Jin Ho; Jin Dae Ho

2014-01-01

In this paper, we give the explicit determinations of dual plane curves, general dual helices and dual slant helices in terms of its dual curvature and dual torsion as a fundamental theory of dual curves in a dual 3-space

Dual energy CT pulmonary blood volume assessment in acute pulmonary embolism - correlation with D-dimer level, right heart strain and clinical outcome

Energy Technology Data Exchange (ETDEWEB)

Bauer, Ralf W.; Frellesen, Claudia; Schell, Boris; Lehnert, Thomas; Jacobi, Volkmar; Vogl, Thomas J.; Kerl, J.M. [Clinic of the Goethe University, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany); Renker, Matthias [Clinic of the Goethe University, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany); Medical University of South Carolina, Heart and Vascular Center, Ashley River Tower, Charleston, SC (United States); Ackermann, Hanns [Clinic of the Goethe University, Department of Biostatistics and Mathematical Modelling, Frankfurt (Germany); Schoepf, U.J. [Medical University of South Carolina, Heart and Vascular Center, Ashley River Tower, Charleston, SC (United States)

2011-09-15

To investigate the role of perfusion defect (PD) size on dual energy CT pulmonary blood volume assessment as predictor of right heart strain and patient outcome and its correlation with d-dimer levels in acute pulmonary embolism (PE). 53 patients with acute PE who underwent DECT pulmonary angiography were retrospectively analyzed. Pulmonary PD size caused by PE was measured on DE iodine maps and quantified absolutely (VolPD) and relatively to the total lung volume (RelPD). Signs of right heart strain (RHS) on CT were determined. Information on d-dimer levels and readmission for recurrent onset of PE and death was collected. D-dimer level was mildly (r = 0.43-0.47) correlated with PD size. Patients with RHS had significantly higher VolPD (215 vs. 73 ml) and RelPD (9.9 vs. 2.9%) than patients without RHS (p < 0.003). There were 2 deaths and 1 readmission due of PE in 18 patients with >5% RelPD, while no such events were found for patients with <5% RelPD. Pulmonary blood volume on DECT in acute PE correlates with RHS and appears to be a predictor of patient outcome in this pilot study. (orig.)

Loop quantum cosmology with self-dual variables

Science.gov (United States)

Wilson-Ewing, Edward

2015-12-01

Using the complex-valued self-dual connection variables, the loop quantum cosmology of a closed Friedmann space-time coupled to a massless scalar field is studied. It is shown how the reality conditions can be imposed in the quantum theory by choosing a particular inner product for the kinematical Hilbert space. While holonomies of the self-dual Ashtekar connection are not well defined in the kinematical Hilbert space, it is possible to introduce a family of generalized holonomylike operators of which some are well defined; these operators in turn are used in the definition of the Hamiltonian constraint operator where the scalar field can be used as a relational clock. The resulting quantum theory is closely related, although not identical, to standard loop quantum cosmology constructed from the Ashtekar-Barbero variables with a real Immirzi parameter. Effective Friedmann equations are derived which provide a good approximation to the full quantum dynamics for sharply peaked states whose volume remains much larger than the Planck volume, and they show that for these states quantum gravity effects resolve the big-bang and big-crunch singularities and replace them by a nonsingular bounce. Finally, the loop quantization in self-dual variables of a flat Friedmann space-time is recovered in the limit of zero spatial curvature and is identical to the standard loop quantization in terms of the real-valued Ashtekar-Barbero variables.

[Design of Dual-Beam Spectrometer in Spectrophotometer for Colorimetry].

Science.gov (United States)

Liu, Yi-xuan; Yan, Chang-xiang

2015-07-01

Spectrophotometers for colorimetry are usually composed of two independent and identical spectrometers. In order to reduce the volume of spectrophotometer for colorimetry, a design method of double-beam spectrometer is put forward. A traditional spectrometer is modified so that a new spectrometer can realize the function of double spectrometers, which is especially suitable for portable instruments. One slit is replaced by the double-slit, than two beams of spectrum can be detected. The working principle and design requirement of double-beam spectrometer are described. A spectrometer of portable spectrophotometer is designed by this method. A toroidal imaging mirror is used for the Czerny-Turner double-beam spectrometer in this paper, which can better correct astigmatism, and prevent the dual-beam spectral crosstalk. The results demonstrate that the double-beam spectrometer designed by this method meets the design specifications, with the spectral resolution less than 10 nm, the spectral length of 9.12 mm, and the volume of 57 mm x 54 mm x 23 mm, and without the dual-beam spectral overlap in the detector either. Comparing with a traditional spectrophotometer, the modified spectrophotometer uses a set of double-beam spectrometer instead of two sets of spectrometers, which can greatly reduce the volume. This design method can be specially applied in portable spectrophotometers, also can be widely applied in other double-beam spectrophotometers, which offers a new idea for the design of dual-beam spectrophotometers.

Highly coherent free-running dual-comb chip platform.

Science.gov (United States)

Hébert, Nicolas Bourbeau; Lancaster, David G; Michaud-Belleau, Vincent; Chen, George Y; Genest, Jérôme

2018-04-15

We characterize the frequency noise performance of a free-running dual-comb source based on an erbium-doped glass chip running two adjacent mode-locked waveguide lasers. This compact laser platform, contained only in a 1.2 L volume, rejects common-mode environmental noise by 20 dB thanks to the proximity of the two laser cavities. Furthermore, it displays a remarkably low mutual frequency noise floor around 10  Hz 2 /Hz, which is enabled by its large-mode-area waveguides and low Kerr nonlinearity. As a result, it reaches a free-running mutual coherence time of 1 s since mode-resolved dual-comb spectra are generated even on this time scale. This design greatly simplifies dual-comb interferometers by enabling mode-resolved measurements without any phase lock.

The Dual Half-Arc data structure: towards the universal B-rep data structure

DEFF Research Database (Denmark)

Anton, François; Bugoslawski, P.; Mioc, Darka

2014-01-01

, or more generally, the topology of any topological space. For this purpose, we generalize an existing data structure from 2D to 3D and design a new 3D data structure that realizes the synthesis between an existing 3D data structure (the Dual Half-Edge (See Footonote 1) data structure) and the generalized...... 3D Quad-Arc data structure, (See Footonote 2) and at the same time, improves the Dual Half-Edge towards a simpler and more effective representation of cell complexes through B-rep structures. We generalize the idea of the Quad-Arc data structure from 2D to 3D, but instead of transforming a simple...... edge of the Quad-Edge data structure to an arc with multiple points along it, we group together primal edges of the Dual Half-Edge that have the same dual Half-Edge vertex tags (volume tags) into one Dual Half-Arc whose dual is the common Dual Half-Edge and primal faces corresponding to dual...

Analysis of the backbone dynamics of interleukin-1β using two-dimensional inverse detected heteronuclear 15N-1H NMR spectroscopy

International Nuclear Information System (INIS)

Clore, G.M.; Driscoll, P.C.; Wingfield, P.T.; Gronenborn, A.M.

1990-01-01

The backbone dynamics of uniformly 15 N-labeled interleukin-1β are investigated by using two-dimensional inverse detected heteronuclear 15 N- 1 H NMR spectroscopy. 15 N T 1 , T 2 , and NOE data at a spectrometer frequency of 600 MHz are obtained for 90% of the backbone amide groups. The data provide evidence for motions on three time scales. All the residues exhibit very fast motions on a time scale of approx-lt 20-50 ps that can be characterized by a single-order parameter with an average value of 0.82 ± 0.05. Thirty-two residues also display motions on a time scale of 0.5-4 ns, slightly less than the overall rotational correlation time of the protein (8.3 ns). While the simple formulation can account for the 15 N T 1 and T 2 data, it fails to account for the 15 N- 1 H NOE data and yields calculated values for the NOEs that are either too small or negative, whereas the observed NOEs are positive. Another 42 residues are characterized by some sort of motion on the 30-ns-10-ms time scale, which results in 15 N line broadening due to chemical exchange between different conformational substates with distinct 15 N chemical shifts. In general, the motions on both the 0.5-4-ns and 30-ns-10-ms time scales are localized in surface-accessible loops and turns connecting the β-strands, as well as at the beginning and end of strands. Finally, the kinetic and equilibrium properties of a slow conformational equilibrium between a major and a minor species, involving at least 19 residues and located on one contiguous face of the molecule, are characterized by using 1 H- 15 N correlation spectroscopy, 1 H- 15 N heteronuclear multiple quantum coherence-nuclear Overhauser enhancement spectroscopy, and 1 H- 1 H nuclear Overhauser enhancement spectroscopy

NMR longitudinal relaxation enhancement in metal halides by heteronuclear polarization exchange during magic-angle spinning

Energy Technology Data Exchange (ETDEWEB)

Shmyreva, Anna A. [Center for Magnetic Resonance, St. Petersburg State University, St. Petersburg 198504 (Russian Federation); Safdari, Majid; Furó, István [Department of Chemistry, KTH Royal Institute of Technology, SE-10044 Stockholm (Sweden); Dvinskikh, Sergey V., E-mail: sergeid@kth.se [Department of Chemistry, KTH Royal Institute of Technology, SE-10044 Stockholm (Sweden); Laboratory of Biomolecular NMR, St. Petersburg State University, St. Petersburg 199034 (Russian Federation)

2016-06-14

Orders of magnitude decrease of {sup 207}Pb and {sup 199}Hg NMR longitudinal relaxation times T{sub 1} upon magic-angle-spinning (MAS) are observed and systematically investigated in solid lead and mercury halides MeX{sub 2} (Me = Pb, Hg and X = Cl, Br, I). In lead(II) halides, the most dramatic decrease of T{sub 1} relative to that in a static sample is in PbI{sub 2}, while it is smaller but still significant in PbBr{sub 2}, and not detectable in PbCl{sub 2}. The effect is magnetic-field dependent but independent of the spinning speed in the range 200–15 000 Hz. The observed relaxation enhancement is explained by laboratory-frame heteronuclear polarization exchange due to crossing between energy levels of spin-1/2 metal nuclei and adjacent quadrupolar-spin halogen nuclei. The enhancement effect is also present in lead-containing organometal halide perovskites. Our results demonstrate that in affected samples, it is the relaxation data recorded under non-spinning conditions that characterize the local properties at the metal sites. A practical advantage of fast relaxation at slow MAS is that spectral shapes with orientational chemical shift anisotropy information well retained can be acquired within a shorter experimental time.

Dual-anticipating, dual and dual-lag synchronization in modulated time-delayed systems

International Nuclear Information System (INIS)

Ghosh, Dibakar; Chowdhury, A. Roy

2010-01-01

In this Letter, dual synchronization in modulated time delay system using delay feedback controller is proposed. Based on Lyapunov stability theory, we suggest a general method to achieve the dual-anticipating, dual, dual-lag synchronization of time-delayed chaotic systems and we find both its existing and sufficient stability conditions. Numerically it is shown that the dual synchronization is also possible when driving system contain two completely different systems. Effect of parameter mismatch on dual synchronization is also discussed. As an example, numerical simulations for the Mackey-Glass and Ikeda systems are conducted, which is in good agreement with the theoretical analysis.

Dual mobility cups provide biomechanical advantages in situations at risk for dislocation: a finite element analysis.

Science.gov (United States)

Terrier, Alexandre; Latypova, Adeliya; Guillemin, Maika; Parvex, Valérie; Guyen, Olivier

2017-03-01

Constrained devices, standard implants with large heads, and dual mobility systems have become popular options to manage instability after total hip arthroplasty (THA). Clinical results with these options have shown variable success rates and significant higher rates of aseptic loosening and mechanical failures with constrained implants. Literature suggests potential advantages of dual mobility, however little is known about its biomechanics. We present a comparative biomechanical study of a standard implant, a constrained implant, and a dual mobility system. A finite element analysis was developed to assess and compare these acetabular options with regard to the range of motion (ROM) to impingement, the angle of dislocation, the resistive torque, the volume of polyethylene (PE) with a stress above 80% of the elastic limit, and the interfacial cup/bone stress. Dual mobility implants provided the greatest ROM to impingement and allowed delaying subluxation and dislocation when compared to standard and constrained implants. Dual mobility also demonstrated the lowest resistive torque at subluxation while the constrained implant provided the greatest one. The lowest critical PE volume was observed with the dual mobility implant, and the highest stress at the interfaces was observed with the constrained implant. This study highlights the biomechanical advantages of dual mobility systems over constrained and standard implants, and is supported by the clinical results reported. Therefore, the use of dual mobility systems in situations at risk for instability should be advocated and constrained implants should be restricted to salvage situations.

The Dual Half-Edge—A Topological Primal/Dual Data Structure and Construction Operators for Modelling and Manipulating Cell Complexes

Directory of Open Access Journals (Sweden)

Pawel Boguslawski

2016-02-01

Full Text Available There is an increasing need for building models that permit interior navigation, e.g., for escape route analysis. This paper presents a non-manifold Computer-Aided Design (CAD data structure, the dual half-edge based on the Poincaré duality that expresses both the geometric representations of individual rooms and their topological relationships. Volumes and faces are expressed as vertices and edges respectively in the dual space, permitting a model just based on the storage of primal and dual vertices and edges. Attributes may be attached to all of these entities permitting, for example, shortest path queries between specified rooms, or to the exterior. Storage costs are shown to be comparable to other non-manifold models, and construction with local Euler-type operators is demonstrated with two large university buildings. This is intended to enhance current developments in 3D Geographic Information Systems for interior and exterior city modelling.

HN-NCA heteronuclear TOCSY-NH experiment for {sup 1}H{sup N} and {sup 15}N sequential correlations in ({sup 13}C, {sup 15}N) labelled intrinsically disordered proteins

Energy Technology Data Exchange (ETDEWEB)

Wiedemann, Christoph; Goradia, Nishit; Häfner, Sabine [Leibniz Institute for Age Research, Fritz Lipmann Institute, Research Group Biomolecular NMR Spectroscopy (Germany); Herbst, Christian [Ubon Ratchathani University, Department of Physics, Faculty of Science (Thailand); Görlach, Matthias; Ohlenschläger, Oliver; Ramachandran, Ramadurai, E-mail: raman@fli-leibniz.de [Leibniz Institute for Age Research, Fritz Lipmann Institute, Research Group Biomolecular NMR Spectroscopy (Germany)

2015-10-15

A simple triple resonance NMR experiment that leads to the correlation of the backbone amide resonances of each amino acid residue ‘i’ with that of residues ‘i−1’ and ‘i+1’ in ({sup 13}C, {sup 15}N) labelled intrinsically disordered proteins (IDPs) is presented. The experimental scheme, {HN-NCA heteronuclear TOCSY-NH}, exploits the favourable relaxation properties of IDPs and the presence of {sup 1}J{sub CαN} and {sup 2}J{sub CαN} couplings to transfer the {sup 15}N{sub x} magnetisation from amino acid residue ‘i’ to adjacent residues via the application of a band-selective {sup 15}N–{sup 13}C{sup α} heteronuclear cross-polarisation sequence of ∼100 ms duration. Employing non-uniform sampling in the indirect dimensions, the efficacy of the approach has been demonstrated by the acquisition of 3D HNN chemical shift correlation spectra of α-synuclein. The experimental performance of the RF pulse sequence has been compared with that of the conventional INEPT-based HN(CA)NH pulse scheme. As the availability of data from both the HCCNH and HNN experiments will make it possible to use the information extracted from one experiment to simplify the analysis of the data of the other and lead to a robust approach for unambiguous backbone and side-chain resonance assignments, a time-saving strategy for the simultaneous collection of HCCNH and HNN data is also described.

Fabrication of dual porosity electrode structure

Science.gov (United States)

Smith, J.L.; Kucera, E.H.

1991-02-12

A substantially entirely fibrous ceramic is described which may have dual porosity of both micro and macro pores. Total porosity may be 60-75% by volume. A method of spraying a slurry perpendicularly to an ambient stream of air is disclosed along with a method of removing binders without altering the fiber morphology. Adding fine ceramic particulates to the green ceramic fibers enhances the sintering characteristics of the fibers. 3 figures.

Development and Use of the Dual-Mode Plasma Torch

International Nuclear Information System (INIS)

Womack, R.; Shuey, M.

2002-01-01

After several years of development, a commercially available high-temperature treatment system has been developed and installed that treats heterogeneous low-level radioactive waste. High temperature plasma processing, unique torch design and operating features make it feasible to achieve a volume reduced, permanent, high integrity waste form while eliminating the personnel exposure and costs associated with conventional sorting, characterizing and handling. Plasma technology can also be used to treat previous conditioned waste packages that no longer meet the current acceptance criteria for final disposal. Plasma treatment can result, in many cases, in a substantial volume reduction, which lowers the final disposal costs. This paper covers the recently patented dual mode plasma torch design(1), the lessons learned that fostered its development and the advantages it brings to radioactive waste processing. This paper also provides current full scale Plasma Arc Centrifugal Treatment (PACT) project status and how the dual mode torch is being used in the PACT system

Dual Entwining Structures and Dual Entwined Modules

OpenAIRE

Abuhlail, Jawad Y.

2003-01-01

In this note we introduce and investigate the concepts of dual entwining structures and dual entwined modules. This generalizes the concepts of dual Doi-Koppinen structures and dual Doi-Koppinen modules introduced (in the infinite case over rings) by the author is his dissertation.

Broadband cross-polarization-based heteronuclear dipolar recoupling for structural and dynamic NMR studies of rigid and soft solids

International Nuclear Information System (INIS)

Kharkov, B. B.; Chizhik, V. I.; Dvinskikh, S. V.

2016-01-01

Dipolar recoupling is an essential part of current solid-state NMR methodology for probing atomic-resolution structure and dynamics in solids and soft matter. Recently described magic-echo amplitude- and phase-modulated cross-polarization heteronuclear recoupling strategy aims at efficient and robust recoupling in the entire range of coupling constants both in rigid and highly dynamic molecules. In the present study, the properties of this recoupling technique are investigated by theoretical analysis, spin-dynamics simulation, and experimentally. The resonance conditions and the efficiency of suppressing the rf field errors are examined and compared to those for other recoupling sequences based on similar principles. The experimental data obtained in a variety of rigid and soft solids illustrate the scope of the method and corroborate the results of analytical and numerical calculations. The technique benefits from the dipolar resolution over a wider range of coupling constants compared to that in other state-of-the-art methods and thus is advantageous in studies of complex solids with a broad range of dynamic processes and molecular mobility degrees

Diagnosis value of dual-phase contrast enhancement CT combined with virtual non-enhanced images by dual-energy CT in clear cell renal cell carcinoma

International Nuclear Information System (INIS)

Ma Zhoupeng; Zhou Jianjun; Liu Xueling; Wang Chun; Zhang Shunzhuang

2012-01-01

Objective: To explore the diagnostic value of dual-phase contrast enhancement CT combined with virtual non-enhanced images by dual-energy CT in clear cell renal cell carcinoma. Methods: Sixty patients who were suspected of clear cell renal cell carcinoma underwent non-enhanced CT and contrast enhancement CT of early interface-phase between cortex -medulla and parenchymal phase on a dual-energy CT. The true non-enhanced kidney CT (TNCT) was performed in a single-energy acquisition mode, but the dual-phase contrast enhancement CT were performed in a dual-energy mode of 80 kV and 140 kV respectively. The virtual non-enhanced CT (VNCT) images were derived from the data of early interface phase using liver virtual non-contrast software. The diagnose according to VNCT combined dual-phase contrast enhancement CT and dual-phase contrast enhancement CT only were made respectively and compared with χ 2 test. Between the true non-contrast CT and the virtual non-contrast CT, the image quality was compared with Wilcoxon test; The radiation dose of volume CT dose index (CTDIvol) and dose length product(DLP) in a single-phase and total examination, the mean CT HU values of the tumours were compared with t test. Results: The accuracy of VNCT combined dual-phase contrast enhancement CT was higher than that of dual-phase contrast enhancement CT only [93.3% (56/60) vs.78.3% (47/60); χ 2 =5.6, P<0.05]. The detective ability (score) of VNCT was near to that of TNCT and the difference was not obvious (Z=0.00, P>0.05). The radiation dose of volume CT dose index (CTDIvol) and dose length product (DLP) in a single phase and total examination of VNCT [(8.85 ± 1.28) mGy, (196.45 ±21.12) mGy·cm, (17.69±2.35) mGy, (392.90±42.25) mGy · cm] were lower than that of TNCT [(10.20 ± 1.44) mGy,(218.29 ± 29.60) mGy · cm, (30.61 ± 3.27) mGy and (654.86 ± 88.81) mGy ·cm], t=4.21, 3.58, 23.63, 16.12 respectively, P<0.05. The mean CT HU values of tumours on VNCT images was higher than that

Improved atom number with a dual color magneto—optical trap

International Nuclear Information System (INIS)

Cao Qiang; Luo Xin-Yu; Gao Kui-Yi; Wang Xiao-Rui; Wang Ru-Quan; Chen Dong-Min

2012-01-01

We demonstrate a novel dual color magneto—optical trap (MOT), which uses two sets of overlapping laser beams to cool and trap 87 Rb atoms. The volume of cold cloud in the dual color MOT is strongly dependent on the frequency difference of the laser beams and can be significantly larger than that in the normal MOT with single frequency MOT beams. Our experiment shows that the dual color MOT has the same loading rate as the normal MOT, but much longer loading time, leading to threefold increase in the number of trapped atoms. This indicates that the larger number is caused by reduced light induced loss. The dual color MOT is very useful in experiments where both high vacuum level and large atom number are required, such as single chamber quantum memory and Bose—Einstein condensation (BEC) experiments. Compared to the popular dark spontaneous-force optical trap (dark SPOT) technique, our approach is technically simpler and more suitable to low power laser systems. (rapid communication)

Calcium scoring with dual-energy CT in men and women: an anthropomorphic phantom study

Science.gov (United States)

Li, Qin; Liu, Songtao; Myers, Kyle; Gavrielides, Marios A.; Zeng, Rongping; Sahiner, Berkman; Petrick, Nicholas

2016-03-01

This work aimed to quantify and compare the potential impact of gender differences on coronary artery calcium scoring with dual-energy CT. An anthropomorphic thorax phantom with four synthetic heart vessels (diameter 3-4.5 mm: female/male left main and left circumflex artery) were scanned with and without female breast plates. Ten repeat scans were acquired in both single- and dual-energy modes and reconstructed at six reconstruction settings: two slice thicknesses (3 mm, 0.6 mm) and three reconstruction algorithms (FBP, IR3, IR5). Agatston and calcium volume scores were estimated from the reconstructed data using a segmentation-based approach. Total calcium score (summation of four vessels), and male/female calcium scores (summation of male/female vessels scanned in phantom without/with breast plates) were calculated accordingly. Both Agatston and calcium volume scores were found comparable between single- and dual-energy scans (Pearson r= 0.99, pwomen and men in calcium scoring, and for standardizing imaging protocols for improved gender-specific calcium scoring.

Impact of Martensite Spatial Distribution on Quasi-Static and Dynamic Deformation Behavior of Dual-Phase Steel

Science.gov (United States)

Singh, Manpreet; Das, Anindya; Venugopalan, T.; Mukherjee, Krishnendu; Walunj, Mahesh; Nanda, Tarun; Kumar, B. Ravi

2018-02-01

The effects of microstructure parameters of dual-phase steels on tensile high strain dynamic deformation characteristic were examined in this study. Cold-rolled steel sheets were annealed using three different annealing process parameters to obtain three different dual-phase microstructures of varied ferrite and martensite phase fraction. The volume fraction of martensite obtained in two of the steels was near identical ( 19 pct) with a subtle difference in its spatial distribution. In the first microstructure variant, martensite was mostly found to be situated at ferrite grain boundaries and in the second variant, in addition to at grain boundaries, in-grain martensite was also observed. The third microstructure was very different from the above two with respect to martensite volume fraction ( 67 pct) and its morphology. In this case, martensite packets were surrounded by a three-dimensional ferrite network giving an appearance of core and shell type microstructure. All the three steels were tensile deformed at strain rates ranging from 2.7 × 10-4 (quasi-static) to 650 s-1 (dynamic range). Field-emission scanning electron microscope was used to characterize the starting as well as post-tensile deformed microstructures. Dual-phase steel consisting of small martensite volume fraction ( 19 pct), irrespective of its spatial distribution, demonstrated high strain rate sensitivity and on the other hand, steel with large martensite volume fraction ( 67 pct) displayed a very little strain rate sensitivity. Interestingly, total elongation was found to increase with increasing strain rate in the dynamic regime for steel with core-shell type of microstructure containing large martensite volume fraction. The observed enhancement in plasticity in dynamic regime was attributed to adiabatic heating of specimen. To understand the evolving damage mechanism, the fracture surface and the vicinity of fracture ends were studied in all the three dual-phase steels.

Low contrast medium-volume third-generation dual-source computed tomography angiography for transcatheter aortic valve replacement planning

Energy Technology Data Exchange (ETDEWEB)

Felmly, Lloyd M. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiothoracic Surgery, Department of Surgery, Charleston, SC (United States); De Cecco, Carlo N.; Varga-Szemes, Akos; McQuiston, Andrew D. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Schoepf, U.J.; Litwin, Sheldon E.; Bayer, Richard R. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiology, Department of Medicine, Charleston, SC (United States); Mangold, Stefanie [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University Hospital of Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany); Vogl, Thomas J. [University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany); Wichmann, Julian L. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany)

2017-05-15

To investigate feasibility, image quality and safety of low-tube-voltage, low-contrast-volume comprehensive cardiac and aortoiliac CT angiography (CTA) for planning transcatheter aortic valve replacement (TAVR). Forty consecutive TAVR candidates prospectively underwent combined CTA of the aortic root and vascular access route (270 mgI/ml iodixanol). Patients were assigned to group A (second-generation dual-source CT [DSCT], 100 kV, 60 ml contrast, 4.0 ml/s flow rate) or group B (third-generation DSCT, 70 kV, 40 ml contrast, 2.5 ml/s flow rate). Vascular attenuation, noise, signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were compared. Subjective image quality was assessed by two observers. Estimated glomerular filtration (eGFR) at CTA and follow-up were measured. Besides a higher body-mass-index in group B (24.8±3.8 kg/m{sup 2} vs. 28.1±5.4 kg/m{sup 2}, P=0.0339), patient characteristics between groups were similar (P≥0.0922). Aortoiliac SNR (P=0.0003) was higher in group B. Cardiac SNR (P=0.0003) and CNR (P=0.0181) were higher in group A. Subjective image quality was similar (P≥0.213) except for aortoiliac image noise (4.42 vs. 4.12, P=0.0374). TAVR-planning measurements were successfully obtained in all patients. There were no significant changes in eGFR among and between groups during follow-up (P≥0.302). TAVR candidates can be safely and effectively evaluated by a comprehensive CTA protocol with low contrast volume using low-tube-voltage acquisition. (orig.)

Low contrast medium-volume third-generation dual-source computed tomography angiography for transcatheter aortic valve replacement planning

International Nuclear Information System (INIS)

Felmly, Lloyd M.; De Cecco, Carlo N.; Varga-Szemes, Akos; McQuiston, Andrew D.; Schoepf, U.J.; Litwin, Sheldon E.; Bayer, Richard R.; Mangold, Stefanie; Vogl, Thomas J.; Wichmann, Julian L.

2017-01-01

To investigate feasibility, image quality and safety of low-tube-voltage, low-contrast-volume comprehensive cardiac and aortoiliac CT angiography (CTA) for planning transcatheter aortic valve replacement (TAVR). Forty consecutive TAVR candidates prospectively underwent combined CTA of the aortic root and vascular access route (270 mgI/ml iodixanol). Patients were assigned to group A (second-generation dual-source CT [DSCT], 100 kV, 60 ml contrast, 4.0 ml/s flow rate) or group B (third-generation DSCT, 70 kV, 40 ml contrast, 2.5 ml/s flow rate). Vascular attenuation, noise, signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were compared. Subjective image quality was assessed by two observers. Estimated glomerular filtration (eGFR) at CTA and follow-up were measured. Besides a higher body-mass-index in group B (24.8±3.8 kg/m 2 vs. 28.1±5.4 kg/m 2 , P=0.0339), patient characteristics between groups were similar (P≥0.0922). Aortoiliac SNR (P=0.0003) was higher in group B. Cardiac SNR (P=0.0003) and CNR (P=0.0181) were higher in group A. Subjective image quality was similar (P≥0.213) except for aortoiliac image noise (4.42 vs. 4.12, P=0.0374). TAVR-planning measurements were successfully obtained in all patients. There were no significant changes in eGFR among and between groups during follow-up (P≥0.302). TAVR candidates can be safely and effectively evaluated by a comprehensive CTA protocol with low contrast volume using low-tube-voltage acquisition. (orig.)

Design of an ultra-thin dual band infrared system

Science.gov (United States)

Du, Ke; Cheng, Xuemin; Lv, Qichao; Hu, YiFei

2014-11-01

The ultra-thin imaging system using reflective multiple-fold structure has smaller volume and less weight while maintaining high resolution compared with conventional optical systems. The multi-folded approach can significantly extend focal distance within wide spectral range without incurring chromatic aberrations. In this paper, we present a dual infrared imaging system of four-folded reflection with two air-spaced concentric reflective surfaces. The dual brand IR system has 107mm effective focal length, 0.7NA, +/-4° FOV, and 50mm effective aperture with 80mm outer diameter into a 25mm total thickness, which spectral response is 3~12μm.

Postmortem validation of breast density using dual-energy mammography

Energy Technology Data Exchange (ETDEWEB)

Molloi, Sabee, E-mail: symolloi@uci.edu; Ducote, Justin L.; Ding, Huanjun; Feig, Stephen A. [Department of Radiological Sciences, University of California, Irvine, California 92697 (United States)

2014-08-15

Purpose: Mammographic density has been shown to be an indicator of breast cancer risk and also reduces the sensitivity of screening mammography. Currently, there is no accepted standard for measuring breast density. Dual energy mammography has been proposed as a technique for accurate measurement of breast density. The purpose of this study is to validate its accuracy in postmortem breasts and compare it with other existing techniques. Methods: Forty postmortem breasts were imaged using a dual energy mammography system. Glandular and adipose equivalent phantoms of uniform thickness were used to calibrate a dual energy basis decomposition algorithm. Dual energy decomposition was applied after scatter correction to calculate breast density. Breast density was also estimated using radiologist reader assessment, standard histogram thresholding and a fuzzy C-mean algorithm. Chemical analysis was used as the reference standard to assess the accuracy of different techniques to measure breast composition. Results: Breast density measurements using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean algorithm, and dual energy were in good agreement with the measured fibroglandular volume fraction using chemical analysis. The standard error estimates using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean, and dual energy were 9.9%, 8.6%, 7.2%, and 4.7%, respectively. Conclusions: The results indicate that dual energy mammography can be used to accurately measure breast density. The variability in breast density estimation using dual energy mammography was lower than reader assessment rankings, standard histogram thresholding, and fuzzy C-mean algorithm. Improved quantification of breast density is expected to further enhance its utility as a risk factor for breast cancer.

Postmortem validation of breast density using dual-energy mammography

International Nuclear Information System (INIS)

Molloi, Sabee; Ducote, Justin L.; Ding, Huanjun; Feig, Stephen A.

2014-01-01

Purpose: Mammographic density has been shown to be an indicator of breast cancer risk and also reduces the sensitivity of screening mammography. Currently, there is no accepted standard for measuring breast density. Dual energy mammography has been proposed as a technique for accurate measurement of breast density. The purpose of this study is to validate its accuracy in postmortem breasts and compare it with other existing techniques. Methods: Forty postmortem breasts were imaged using a dual energy mammography system. Glandular and adipose equivalent phantoms of uniform thickness were used to calibrate a dual energy basis decomposition algorithm. Dual energy decomposition was applied after scatter correction to calculate breast density. Breast density was also estimated using radiologist reader assessment, standard histogram thresholding and a fuzzy C-mean algorithm. Chemical analysis was used as the reference standard to assess the accuracy of different techniques to measure breast composition. Results: Breast density measurements using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean algorithm, and dual energy were in good agreement with the measured fibroglandular volume fraction using chemical analysis. The standard error estimates using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean, and dual energy were 9.9%, 8.6%, 7.2%, and 4.7%, respectively. Conclusions: The results indicate that dual energy mammography can be used to accurately measure breast density. The variability in breast density estimation using dual energy mammography was lower than reader assessment rankings, standard histogram thresholding, and fuzzy C-mean algorithm. Improved quantification of breast density is expected to further enhance its utility as a risk factor for breast cancer

Comparison the treatment effects between simultaneous dual frequency and single frequency irradiation of ultrasound in a murine model of breast adenocarcinoma

Directory of Open Access Journals (Sweden)

Mahboobeh Alamolhoda

2010-12-01

Full Text Available Introduction: Transient cavitations induced by low frequency irradiation of ultrasound can be used to treat tumors. Previous studies in in-vitro experiments have shown that induced cavitation by dual or multiple frequencies of ultrasound is greater than induced cavitation by single frequency irradiation. In this study, we compared and evaluated the treatment effects of dual frequency irradiation of ultrasound (1 MHz and 150 kHz and single frequency irradiation in in-vivo experiments on breast adenocarcinoma tumors. Material and Method: In this study, the tumor-bearing mice were divided into 5 groups: control, sham, treated group for 30 min with 150 kHz frequency in continuous mode, another group with 1 MHz frequency in pulse mode, and treated group with combined dual frequency ultrasound (150 kHz in continuous mode and 1 MHz in 80% pulse mode. To evaluate the effects of ultrasound irradiation on tumor growth delay, the volumes of the tumors were investigated for 30 days. Tumor growth delay parameters including relative volume, inhibition ratio percentage and the required times for the tumor volume to reach to two (T2 and five (T5 times its initial volume were calculated. Results: The results showed that the treated groups with single frequency irradiation of 150 kHz continuous mode and 1 MHz pulse mode and combined dual frequency had statistically significant differences in tumor relative volume percentage during the period of 3 to 24 days after treatment (p

Dual source and dual detector arrays tetrahedron beam computed tomography for image guided radiotherapy

Science.gov (United States)

Kim, Joshua; Lu, Weiguo; Zhang, Tiezhi

2014-02-01

Cone-beam computed tomography (CBCT) is an important online imaging modality for image guided radiotherapy. But suboptimal image quality and the lack of a real-time stereoscopic imaging function limit its implementation in advanced treatment techniques, such as online adaptive and 4D radiotherapy. Tetrahedron beam computed tomography (TBCT) is a novel online imaging modality designed to improve on the image quality provided by CBCT. TBCT geometry is flexible, and multiple detector and source arrays can be used for different applications. In this paper, we describe a novel dual source-dual detector TBCT system that is specially designed for LINAC radiation treatment machines. The imaging system is positioned in-line with the MV beam and is composed of two linear array x-ray sources mounted aside the electrical portal imaging device and two linear arrays of x-ray detectors mounted below the machine head. The detector and x-ray source arrays are orthogonal to each other, and each pair of source and detector arrays forms a tetrahedral volume. Four planer images can be obtained from different view angles at each gantry position at a frame rate as high as 20 frames per second. The overlapped regions provide a stereoscopic field of view of approximately 10-15 cm. With a half gantry rotation, a volumetric CT image can be reconstructed having a 45 cm field of view. Due to the scatter rejecting design of the TBCT geometry, the system can potentially produce high quality 2D and 3D images with less radiation exposure. The design of the dual source-dual detector system is described, and preliminary results of studies performed on numerical phantoms and simulated patient data are presented.

Heteronuclear Adiabatic Relaxation Dispersion (HARD) for quantitative analysis of conformational dynamics in proteins.

Science.gov (United States)

Traaseth, Nathaniel J; Chao, Fa-An; Masterson, Larry R; Mangia, Silvia; Garwood, Michael; Michaeli, Shalom; Seelig, Burckhard; Veglia, Gianluigi

2012-06-01

NMR relaxation methods probe biomolecular motions over a wide range of timescales. In particular, the rotating frame spin-lock R(1ρ) and Carr-Purcell-Meiboom-Gill (CPMG) R(2) experiments are commonly used to characterize μs to ms dynamics, which play a critical role in enzyme folding and catalysis. In an effort to complement these approaches, we introduced the Heteronuclear Adiabatic Relaxation Dispersion (HARD) method, where dispersion in rotating frame relaxation rate constants (longitudinal R(1ρ) and transverse R(2ρ)) is created by modulating the shape and duration of adiabatic full passage (AFP) pulses. Previously, we showed the ability of the HARD method to detect chemical exchange dynamics in the fast exchange regime (k(ex)∼10(4)-10(5) s(-1)). In this article, we show the sensitivity of the HARD method to slower exchange processes by measuring R(1ρ) and R(2ρ) relaxation rates for two soluble proteins (ubiquitin and 10C RNA ligase). One advantage of the HARD method is its nominal dependence on the applied radio frequency field, which can be leveraged to modulate the dispersion in the relaxation rate constants. In addition, we also include product operator simulations to define the dynamic range of adiabatic R(1ρ) and R(2ρ) that is valid under all exchange regimes. We conclude from both experimental observations and simulations that this method is complementary to CPMG-based and rotating frame spin-lock R(1ρ) experiments to probe conformational exchange dynamics for biomolecules. Finally, this approach is germane to several NMR-active nuclei, where relaxation rates are frequency-offset independent. Copyright © 2012 Elsevier Inc. All rights reserved.

Studies on sampling and homogeneous dual readout calorimetry with meta-crystals

CERN Document Server

Mavromanolakis, G; Lecoq, P

2011-01-01

The meta-crystals concept is an approach that consists of using both undoped and properly doped heavy crystal fibers of identical material as the active medium of a calorimeter. The undoped fibers behave as Cherenkov radiators while the doped ones behave as scintillators. A dual readout calorimeter can be built with its sensitive volume composed of a mixture of both types of crystals. In addition if the calorimeter is adequately finely segmented it can also function as a particle flow calorimeter at the same time. In this way one could possibly combine the advantages of both the particle flow concept and the dual readout scheme. We discuss the approach of dual readout calorimetry with meta-crystals made of Lutetium Aluminium Garnet (LuAG). We brie fly present studies on the material development and first testbeam activities and then focus on performance expectation studies based on simulation. We discuss in more detail the results from generic systematic scannings of the design parameters of a dual readout ca...

Design improvement of permanent magnet flux switching motor with dual rotor structure

Science.gov (United States)

Soomro, H. A.; Sulaiman, E.; Kumar, R.; Rahim, N. S.

2017-08-01

This paper presents design enhancement to reduce permanent magnet (PM) volume for 7S-6P-7S dual rotor permanent magnet flux-switching machines (DRPMFSM) for electric vehicle application. In recent years, Permanent magnet flux switching (PMFS) motor and a new member of brushless permanent magnet machine are prominently used for the electric vehicle. Though, more volume of Rare-Earth Permanent Magnet (REPM) is used to increase the cost and weight of these motors. Thus, to overcome the issue, new configuration of 7S-6P- 7S dual rotor permanent magnet flux-switching machine (DRPMFSM) has been proposed and investigated in this paper. Initially proposed 7S-6P-7S DRPMFSM has been optimized using “deterministic optimization” to reduce the volume of PM and to attain optimum performances. In addition, the performances of initial and optimized DRPMFSM have been compared such that back-emf, cogging torque, average torque, torque and power vs speed performances, losses and efficiency have been analysed by 2D-finite element analysis (FEA) using the JMAG- Designer software ver. 14.1. Consequently, the final design 7S-6P-7S DRPMFSM has achieved the efficiency of 83.91% at reduced PM volume than initial design to confirm the better efficient motor for HEVs applications.

Some properties of dual and approximate dual of fusion frames

OpenAIRE

Arefijamaal, Ali Akbar; Neyshaburi, Fahimeh Arabyani

2016-01-01

In this paper we extend the notion of approximate dual to fusion frames and present some approaches to obtain dual and approximate alternate dual fusion frames. Also, we study the stability of dual and approximate alternate dual fusion frames.

The effects of iodine attenuation on pulmonary nodule volumetry using novel dual-layer computed tomography reconstructions

Energy Technology Data Exchange (ETDEWEB)

Harder, A.M. den; Hamersvelt, R.W. van; Leiner, T.; Schilham, A.M.R.; Willemink, M.J.; Jong, P.A. de [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Bangert, F. [Sint Antonius Ziekenhuis, Department of Radiology, Nieuwegein (Netherlands); Milles, Julien [Philips Healthcare, Best (Netherlands)

2017-12-15

To assess the effect of iodine attenuation on pulmonary nodule volumetry using virtual non-contrast (VNC) and mono-energetic reconstructions. A consecutive series of patients who underwent a contrast-enhanced chest CT scan were included. Images were acquired on a novel dual-layer spectral CT system. Conventional reconstructions as well as VNC and mono-energetic images at different keV levels were used for nodule volumetry. Twenty-four patients with a total of 63 nodules were included. Conventional reconstructions showed a median (interquartile range) volume and diameter of 174 (87 - 253) mm{sup 3} and 6.9 (5.4 - 9.9) mm, respectively. VNC reconstructions resulted in a significant volume reduction of 5.5% (2.6 - 11.2%; p<0.001). Mono-energetic reconstructions showed a correlation between nodule attenuation and nodule volume (Spearman correlation 0.77, (0.49 - 0.94)). Lowering the keV resulted in increased volumes while higher keV levels resulted in decreased pulmonary nodule volumes compared to conventional CT. Novel dual-layer spectral CT offers the possibility to reconstruct VNC and mono-energetic images. Those reconstructions show that higher pulmonary nodule attenuation results in larger nodule volumes. This may explain the reported underestimation in nodule volume on non-contrast enhanced compared to contrast-enhanced acquisitions. (orig.)

The effects of iodine attenuation on pulmonary nodule volumetry using novel dual-layer computed tomography reconstructions

International Nuclear Information System (INIS)

Harder, A.M. den; Hamersvelt, R.W. van; Leiner, T.; Schilham, A.M.R.; Willemink, M.J.; Jong, P.A. de; Bangert, F.; Milles, Julien

2017-01-01

To assess the effect of iodine attenuation on pulmonary nodule volumetry using virtual non-contrast (VNC) and mono-energetic reconstructions. A consecutive series of patients who underwent a contrast-enhanced chest CT scan were included. Images were acquired on a novel dual-layer spectral CT system. Conventional reconstructions as well as VNC and mono-energetic images at different keV levels were used for nodule volumetry. Twenty-four patients with a total of 63 nodules were included. Conventional reconstructions showed a median (interquartile range) volume and diameter of 174 (87 - 253) mm 3 and 6.9 (5.4 - 9.9) mm, respectively. VNC reconstructions resulted in a significant volume reduction of 5.5% (2.6 - 11.2%; p<0.001). Mono-energetic reconstructions showed a correlation between nodule attenuation and nodule volume (Spearman correlation 0.77, (0.49 - 0.94)). Lowering the keV resulted in increased volumes while higher keV levels resulted in decreased pulmonary nodule volumes compared to conventional CT. Novel dual-layer spectral CT offers the possibility to reconstruct VNC and mono-energetic images. Those reconstructions show that higher pulmonary nodule attenuation results in larger nodule volumes. This may explain the reported underestimation in nodule volume on non-contrast enhanced compared to contrast-enhanced acquisitions. (orig.)

Structural control of void formation in dual phase steels

DEFF Research Database (Denmark)

Azuma, Masafumi

The objective of this study is to explore the void formation mechanisms and to clarify the influence of the hardness and structural parameters (volume fraction, size and morphology) of martensite particles on the void formation and mechanical properties in dual phase steels composed of ferrite...... and (iii) strain localization. The critical strain for void formation depends on hardness of the martensite, but is independent of the volume fraction, shape, size and distribution of the martensite. The strain partitioning between the martensite and ferrite depends on the volume fraction and hardness...... of the martensite accelerates the void formation in the martensite by enlarging the size of voids both in the martensite and ferrite. It is suggested that controlling the hardness and structural parameters associated with the martensite particles such as morphology, size and volume fraction are the essential...

Activation and thermodynamic parameter study of the heteronuclear C=O···H-N hydrogen bonding of diphenylurethane isomeric structures by FT-IR spectroscopy using the regularized inversion of an eigenvalue problem.

Science.gov (United States)

Spegazzini, Nicolas; Siesler, Heinz W; Ozaki, Yukihiro

2012-08-02

The doublet of the ν(C=O) carbonyl band in isomeric urethane systems has been extensively discussed in qualitative terms on the basis of FT-IR spectroscopy of the macromolecular structures. Recently, a reaction extent model was proposed as an inverse kinetic problem for the synthesis of diphenylurethane for which hydrogen-bonded and non-hydrogen-bonded C=O functionalities were identified. In this article, the heteronuclear C=O···H-N hydrogen bonding in the isomeric structure of diphenylurethane synthesized from phenylisocyanate and phenol was investigated via FT-IR spectroscopy, using a methodology of regularization for the inverse reaction extent model through an eigenvalue problem. The kinetic and thermodynamic parameters of this system were derived directly from the spectroscopic data. The activation and thermodynamic parameters of the isomeric structures of diphenylurethane linked through a hydrogen bonding equilibrium were studied. The study determined the enthalpy (ΔH = 15.25 kJ/mol), entropy (TΔS = 14.61 kJ/mol), and free energy (ΔG = 0.6 kJ/mol) of heteronuclear C=O···H-N hydrogen bonding by FT-IR spectroscopy through direct calculation from the differences in the kinetic parameters (δΔ(‡)H, -TδΔ(‡)S, and δΔ(‡)G) at equilibrium in the chemical reaction system. The parameters obtained in this study may contribute toward a better understanding of the properties of, and interactions in, supramolecular systems, such as the switching behavior of hydrogen bonding.

Ultrasound findings in dual kidney transplantation.

Science.gov (United States)

Damasio, M B; Cittadini, G; Rolla, D; Massarino, F; Stagnaro, N; Gherzi, M; Paoletti, E; Derchi, L E

2013-02-01

This study was done to analyse colour Doppler ultrasound (CDUS) findings in patients with dual kidney transplantation (DKT) and to compare renal volume and resistive index (RI) values between DKT and single kidney transplantation (SKT). We reviewed the clinical and imaging findings [30 CDUS, five magnetic resonance (MR) and one computed tomography (CT) examination] in 30 patients with DKT (23 men and seven women; median age 65 years; range 55-82). Three patients had clinical signs of graft malfunction. Renal volumes and RI were compared with those of 14 SKT patients and comparable levels of renal function. Three patients had graft dysfunction: one had chronic rejection and two had pathologies involving one kidney only (one encrusted pyeloureteritis of a left graft and one occluded main artery of a left graft). Asymptomatic unilateral pathologies were seen in six cases. In asymptomatic DKT patients, no significant differences in length, volume, cortical echogenicity and RI between the two kidneys were observed; DKTs were smaller (median volume 116.7 vs. 171.6 cc) and had higher RIs (0.76 vs. 0.68) (pDKT, allowing detection of clinically unsuspected unilateral diseases. At comparable levels of renal function, DKT patients had higher RI and lower volumes than SKT patients.

Establishment of animal model of dual liver transplantation in rat.

Directory of Open Access Journals (Sweden)

Ying Zhang

Full Text Available The animal model of the whole-size and reduced-size liver transplantation in both rat and mouse has been successfully established. Because of the difficulties and complexities in microsurgical technology, the animal model of dual liver transplantation was still not established for twelve years since the first human dual liver transplantation has been made a success. There is an essential need to establish this animal model to lay a basic foundation for clinical practice. To study the physiological and histopathological changes of dual liver transplantation, "Y" type vein from the cross part between vena cava and two iliac of donor and "Y' type prosthesis were employed to recanalize portal vein and the bile duct between dual liver grafts and recipient. The dual right upper lobes about 45-50% of the recipient liver volume were taken as donor, one was orthotopically implanted at its original position, the other was rotated 180° sagitally and heterotopically positioned in the left upper quadrant. Microcirculation parameters, liver function, immunohistochemistry and survival were analyzed to evaluate the function of dual liver grafts. No significant difference in the hepatic microcirculatory flow was found between two grafts in the first 90 minutes after reperfusion. Light and electronic microscope showed the liver architecture was maintained without obvious features of cellular destruction and the continuity of the endothelium was preserved. Only 3 heterotopically positioned graft appeared patchy desquamation of endothelial cell, mitochondrial swelling and hepatocytes cytoplasmic vacuolization. Immunohistochemistry revealed there is no difference in hepatocyte activity and the ability of endothelia to contract and relax after reperfusion between dual grafts. Dual grafts made a rapid amelioration of liver function after reperfusion. 7 rats survived more than 7 days with survival rate of 58.3.%. Using "Y" type vein and bile duct prosthesis, we

Mixed-time parallel evolution in multiple quantum NMR experiments: sensitivity and resolution enhancement in heteronuclear NMR

International Nuclear Information System (INIS)

Ying Jinfa; Chill, Jordan H.; Louis, John M.; Bax, Ad

2007-01-01

A new strategy is demonstrated that simultaneously enhances sensitivity and resolution in three- or higher-dimensional heteronuclear multiple quantum NMR experiments. The approach, referred to as mixed-time parallel evolution (MT-PARE), utilizes evolution of chemical shifts of the spins participating in the multiple quantum coherence in parallel, thereby reducing signal losses relative to sequential evolution. The signal in a given PARE dimension, t 1 , is of a non-decaying constant-time nature for a duration that depends on the length of t 2 , and vice versa, prior to the onset of conventional exponential decay. Line shape simulations for the 1 H- 15 N PARE indicate that this strategy significantly enhances both sensitivity and resolution in the indirect 1 H dimension, and that the unusual signal decay profile results in acceptable line shapes. Incorporation of the MT-PARE approach into a 3D HMQC-NOESY experiment for measurement of H N -H N NOEs in KcsA in SDS micelles at 50 o C was found to increase the experimental sensitivity by a factor of 1.7±0.3 with a concomitant resolution increase in the indirectly detected 1 H dimension. The method is also demonstrated for a situation in which homonuclear 13 C- 13 C decoupling is required while measuring weak H3'-2'OH NOEs in an RNA oligomer

Dual source and dual detector arrays tetrahedron beam computed tomography for image guided radiotherapy

International Nuclear Information System (INIS)

Kim, Joshua; Zhang, Tiezhi; Lu, Weiguo

2014-01-01

Cone-beam computed tomography (CBCT) is an important online imaging modality for image guided radiotherapy. But suboptimal image quality and the lack of a real-time stereoscopic imaging function limit its implementation in advanced treatment techniques, such as online adaptive and 4D radiotherapy. Tetrahedron beam computed tomography (TBCT) is a novel online imaging modality designed to improve on the image quality provided by CBCT. TBCT geometry is flexible, and multiple detector and source arrays can be used for different applications. In this paper, we describe a novel dual source–dual detector TBCT system that is specially designed for LINAC radiation treatment machines. The imaging system is positioned in-line with the MV beam and is composed of two linear array x-ray sources mounted aside the electrical portal imaging device and two linear arrays of x-ray detectors mounted below the machine head. The detector and x-ray source arrays are orthogonal to each other, and each pair of source and detector arrays forms a tetrahedral volume. Four planer images can be obtained from different view angles at each gantry position at a frame rate as high as 20 frames per second. The overlapped regions provide a stereoscopic field of view of approximately 10–15 cm. With a half gantry rotation, a volumetric CT image can be reconstructed having a 45 cm field of view. Due to the scatter rejecting design of the TBCT geometry, the system can potentially produce high quality 2D and 3D images with less radiation exposure. The design of the dual source–dual detector system is described, and preliminary results of studies performed on numerical phantoms and simulated patient data are presented. (paper)

Treatment of Murine Tumor Models of Breast Adenocarcinoma by Continuous Dual-Frequency Ultrasound

Directory of Open Access Journals (Sweden)

Amir Hoshang Barati

2009-03-01

Full Text Available Introduction: Acoustic transient cavitation is the primary mechanism of sonochemical reaction and has potential use for tumor treatment. In this study, the in vivo anti-tumor effect of simultaneous dual-frequency ultrasound at low-level intensity (ISATA < 6 W/cm2 was investigated in a spontaneous murine model of breast adenocarcinoma in Balb/c mice. Materials and Methods: Forty tumor bearing mice were divided into four groups (10 in each group. The treated groups received 15 or 30 minutes of combined dual-frequency ultrasound in continuous mode (1 MHzcon + 150 kHzcon respectively. The control and the sham groups contained the untreated mice. The tumor growth delay parameters including tumor volume, relative tumor volume, T5 and T2 (the needed time for each tumor to reach 5 and 2 times the initial tumor volume, respectively, survival period and percent of tumor growth inhibition ratio were measured on different days after treatment. Results: The results showed that the 30 min treatment was effective in tumor growth delay and percent of tumor growth inhibitory ratio compared to the sham and the control groups. The tumor volume growth and relative volume of tumors in the same treated group showed an anti-tumor effect relative to the sham and the control groups. There was a significant difference in tumor volume growth between this 30 min treatment group and the sham group 12 days after treatment (p-value

Haemodynamic effects of dual-chamber pacing versus ventricular pacing during a walk test in patients with depressed or normal left ventricular function

Energy Technology Data Exchange (ETDEWEB)

Ferro, Adele; Salvatore, Marco; Cuocolo, Alberto [University Federico II, Department of Biomorphological and Functional Sciences, Institute of Biostructure and Bioimages of the National Council of Research, Naples (Italy); Duilio, Carlo; Santomauro, Maurizio [University Federico II, Department of Clinical Medicine, Cardiovascular and Immunological Sciences, Naples (Italy)

2005-09-01

Dual-chamber rate-modulated pacing provides haemodynamic benefits compared with ventricular pacing at rest, but it is unclear whether this also holds true during physical exercise in patients with heart failure. This study assessed the haemodynamic response to a walk test during dual-chamber pacing and ventricular pacing in patients with depressed or normal left ventricular (LV) function. Twelve patients with an LV ejection fraction <50% and 11 patients with an LV ejection fraction {>=}50% underwent two randomised 6-min walk tests under dual-chamber rate-modulated pacing and ventricular pacing at a fixed rate of 70 beats/min. All patients had a dual-chamber pacemaker implanted for complete heart block. LV function was monitored by a radionuclide ambulatory system. In patients with depressed LV function, the change from dual-chamber pacing to ventricular pacing induced a decrease in end-systolic volume at the peak of the walk test (P<0.05), with no difference in end-diastolic volume. As a consequence, higher increases in LV ejection fraction (P<0.0001) and stroke volume (P<0.01) were observed during ventricular pacing. No difference in cardiac output was found between the two pacing modes. In patients with normal LV function, the change from dual-chamber pacing to ventricular pacing induced a significant decrease in cardiac output (P<0.005 at rest and P<0.05 at the peak of the walk test). Compared with dual-chamber rate-modulated pacing, ventricular pacing improves cardiac function and does not affect cardiac output during physical activity in patients with depressed LV function, whereas it impairs cardiac output in those with normal function. (orig.)

Haemodynamic effects of dual-chamber pacing versus ventricular pacing during a walk test in patients with depressed or normal left ventricular function

International Nuclear Information System (INIS)

Ferro, Adele; Salvatore, Marco; Cuocolo, Alberto; Duilio, Carlo; Santomauro, Maurizio

2005-01-01

Dual-chamber rate-modulated pacing provides haemodynamic benefits compared with ventricular pacing at rest, but it is unclear whether this also holds true during physical exercise in patients with heart failure. This study assessed the haemodynamic response to a walk test during dual-chamber pacing and ventricular pacing in patients with depressed or normal left ventricular (LV) function. Twelve patients with an LV ejection fraction <50% and 11 patients with an LV ejection fraction ≥50% underwent two randomised 6-min walk tests under dual-chamber rate-modulated pacing and ventricular pacing at a fixed rate of 70 beats/min. All patients had a dual-chamber pacemaker implanted for complete heart block. LV function was monitored by a radionuclide ambulatory system. In patients with depressed LV function, the change from dual-chamber pacing to ventricular pacing induced a decrease in end-systolic volume at the peak of the walk test (P<0.05), with no difference in end-diastolic volume. As a consequence, higher increases in LV ejection fraction (P<0.0001) and stroke volume (P<0.01) were observed during ventricular pacing. No difference in cardiac output was found between the two pacing modes. In patients with normal LV function, the change from dual-chamber pacing to ventricular pacing induced a significant decrease in cardiac output (P<0.005 at rest and P<0.05 at the peak of the walk test). Compared with dual-chamber rate-modulated pacing, ventricular pacing improves cardiac function and does not affect cardiac output during physical activity in patients with depressed LV function, whereas it impairs cardiac output in those with normal function. (orig.)

2D 1H -13C Heteronuclear Shift Correlation Of 2a - Hydroxy Aiantolactone From Pulicaria Undulata C.A. Mey

Directory of Open Access Journals (Sweden)

A. Rustaiyan

1992-07-01

Full Text Available We have reported recently the isolation and characterization of several sesquiterpene lactones from Pulicaria undulata (1."nThe lactones were isolated from an Et20 - Petrol (1:3 fraction by different chromatographic techniques including HPLC (RP 8, MeOH - H2O, 13:7."nIn this way three eudesmanolides 1 - 3, a guaianolide 4, a nor -guaianolide 5, as well as the pseudoguaianolide 6 and the xanthanolide 7 were isolated. One of the eudesmanolides (2a - hydroxy aiantolactone, 1, was present as the main component."nSuch lactones being known as biologically active substances, we have decided to describe for the first time a detailed interpretation of proton, 1H -NMR, 13C - NMR and 2D lH -13C - heteronuclear shift correlation spectra of 2a - hydroxy aiantolactone. The stereochemistry of C - 2 , C - 7 and C - 8 was determined by the NOESY experiments, H - 7 and H - 8 are in the a configuration and H - 2 is in the b configuration.

Dual Credit/Dual Enrollment and Data Driven Policy Implementation

Science.gov (United States)

Lichtenberger, Eric; Witt, M. Allison; Blankenberger, Bob; Franklin, Doug

2014-01-01

The use of dual credit has been expanding rapidly. Dual credit is a college course taken by a high school student for which both college and high school credit is given. Previous studies provided limited quantitative evidence that dual credit/dual enrollment is directly connected to positive student outcomes. In this study, predictive statistics…

Transverse tripolar spinal cord stimulation: theoretical performance of a dual channel system

NARCIS (Netherlands)

Struijk, J.J.; Struijk, J.J.; Holsheimer, J.

1996-01-01

A new approach to spinal cord stimulation is presented, by which several serious problems of conventional methods can be solved. A transverse tripolar electrode with a dual-channel voltage stimulator is evaluated theoretically by means of a volume conductor model, combined with nerve fibre models.

Organ volume estimation using SPECT

CERN Document Server

Zaidi, H

1996-01-01

Knowledge of in vivo thyroid volume has both diagnostic and therapeutic importance and could lead to a more precise quantification of absolute activity contained in the thyroid gland. In order to improve single-photon emission computed tomography (SPECT) quantitation, attenuation correction was performed according to Chang's algorithm. The dual-window method was used for scatter subtraction. We used a Monte Carlo simulation of the SPECT system to accurately determine the scatter multiplier factor k. Volume estimation using SPECT was performed by summing up the volume elements (voxels) lying within the contour of the object, determined by a fixed threshold and the gray level histogram (GLH) method. Thyroid phantom and patient studies were performed and the influence of 1) fixed thresholding, 2) automatic thresholding, 3) attenuation, 4) scatter, and 5) reconstruction filter were investigated. This study shows that accurate volume estimation of the thyroid gland is feasible when accurate corrections are perform...

Temporal lobe developmental malformations and epilepsy: dual pathology and bilateral hippocampal abnormalities.

Science.gov (United States)

Ho, S S; Kuzniecky, R I; Gilliam, F; Faught, E; Morawetz, R

1998-03-01

Temporal lobe developmental malformations (TLDM) with focal cortical dysplasia and balloon cells may coexist with mesial temporal sclerosis. The true incidence of this dual pathology is unknown. Our aim was to assess the frequency of amygdala (AM)-hippocampal abnormality in a homogeneous population with this specific developmental malformation. MRI-based volumetry of the AM and hippocampal formation (HF) in 30 patients with unilateral TLDM and intractable partial epilepsy was performed. A volume normalization process defined a normal range of HF and AM volumes in control subjects, and enabled the detection of bilateral volume loss. Normalized volumes detected HF atrophy in 26 patients (nine unilateral and 17 bilateral) and AM atrophy in 18 patients (three unilateral and 15 bilateral). Visual analysis detected unilateral HF abnormality in 21 patients and bilateral abnormality in two. When compared with a group of patients with temporal lobe epilepsy and pure hippocampal sclerosis (N = 92), where volumetry revealed bilateral HF atrophy in 18%, a significant difference in the frequency of bilateral HF atrophy was found (p Dual pathology is frequent in patients with TLDM (87%), and the AM-HF abnormality is often bilateral (57%). Our data suggest that more widespread and potentially epileptogenic lesions coexist with visibly detectable unilateral TLDM. This has implications for the selection of patients for temporal lobe surgery and may influence surgical strategies.

Quantifying [{sup 18}F]fluorodeoxyglucose uptake in the arterial wall: the effects of dual time-point imaging and partial volume effect correction

Energy Technology Data Exchange (ETDEWEB)

Blomberg, Bjoern A. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Odense University Hospital, Department of Nuclear Medicine, Odense (Denmark); Bashyam, Arjun; Ramachandran, Abhinay; Gholami, Saeid; Houshmand, Sina; Salavati, Ali; Werner, Tom; Alavi, Abass [Hospital of the University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States); Zaidi, Habib [Geneva University Hospital, Division of Nuclear Medicine and Molecular Imaging, Geneva (Switzerland); University of Groningen, Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, Groningen (Netherlands)

2015-08-15

The human arterial wall is smaller than the spatial resolution of current positron emission tomographs. Therefore, partial volume effects should be considered when quantifying arterial wall {sup 18}F-FDG uptake. We evaluated the impact of a novel method for partial volume effect (PVE) correction with contrast-enhanced CT (CECT) assistance on quantification of arterial wall {sup 18}F-FDG uptake at different imaging time-points. Ten subjects were assessed by CECT imaging and dual time-point PET/CT imaging at approximately 60 and 180 min after {sup 18}F-FDG administration. For both time-points, uptake of {sup 18}F-FDG was determined in the aortic wall by calculating the blood pool-corrected maximum standardized uptake value (cSUV{sub MAX}) and cSUV{sub MEAN}. The PVE-corrected SUV{sub MEAN} (pvcSUV{sub MEAN}) was also calculated using {sup 18}F-FDG PET/CT and CECT images. Finally, corresponding target-to-background ratios (TBR) were calculated. At 60 min, pvcSUV{sub MEAN} was on average 3.1 times greater than cSUV{sub MAX} (P <.0001) and 8.5 times greater than cSUV{sub MEAN} (P <.0001). At 180 min, pvcSUV{sub MEAN} was on average 2.6 times greater than cSUV{sub MAX} (P <.0001) and 6.6 times greater than cSUV{sub MEAN} (P <.0001). This study demonstrated that CECT-assisted PVE correction significantly influences quantification of arterial wall {sup 18}F-FDG uptake. Therefore, partial volume effects should be considered when quantifying arterial wall {sup 18}F-FDG uptake with PET. (orig.)

Dual-resolution dose assessments for proton beamlet using MCNPX 2.6.0

Science.gov (United States)

Chao, T. C.; Wei, S. C.; Wu, S. W.; Tung, C. J.; Tu, S. J.; Cheng, H. W.; Lee, C. C.

2015-11-01

The purpose of this study is to access proton dose distribution in dual resolution phantoms using MCNPX 2.6.0. The dual resolution phantom uses higher resolution in Bragg peak, area near large dose gradient, or heterogeneous interface and lower resolution in the rest. MCNPX 2.6.0 was installed in Ubuntu 10.04 with MPI for parallel computing. FMesh1 tallies were utilized to record the energy deposition which is a special designed tally for voxel phantoms that converts dose deposition from fluence. 60 and 120 MeV narrow proton beam were incident into Coarse, Dual and Fine resolution phantoms with pure water, water-bone-water and water-air-water setups. The doses in coarse resolution phantoms are underestimated owing to partial volume effect. The dose distributions in dual or high resolution phantoms agreed well with each other and dual resolution phantoms were at least 10 times more efficient than fine resolution one. Because the secondary particle range is much longer in air than in water, the dose of low density region may be under-estimated if the resolution or calculation grid is not small enough.

The Effects of Iodine Attenuation on Pulmonary Nodule Volumetry using Novel Dual-Layer Computed Tomography Reconstructions.

Science.gov (United States)

den Harder, A M; Bangert, F; van Hamersvelt, R W; Leiner, T; Milles, Julien; Schilham, A M R; Willemink, M J; de Jong, P A

2017-12-01

To assess the effect of iodine attenuation on pulmonary nodule volumetry using virtual non-contrast (VNC) and mono-energetic reconstructions. A consecutive series of patients who underwent a contrast-enhanced chest CT scan were included. Images were acquired on a novel dual-layer spectral CT system. Conventional reconstructions as well as VNC and mono-energetic images at different keV levels were used for nodule volumetry. Twenty-four patients with a total of 63 nodules were included. Conventional reconstructions showed a median (interquartile range) volume and diameter of 174 (87 - 253) mm 3 and 6.9 (5.4 - 9.9) mm, respectively. VNC reconstructions resulted in a significant volume reduction of 5.5% (2.6 - 11.2%; p<0.001). Mono-energetic reconstructions showed a correlation between nodule attenuation and nodule volume (Spearman correlation 0.77, (0.49 - 0.94)). Lowering the keV resulted in increased volumes while higher keV levels resulted in decreased pulmonary nodule volumes compared to conventional CT. Novel dual-layer spectral CT offers the possibility to reconstruct VNC and mono-energetic images. Those reconstructions show that higher pulmonary nodule attenuation results in larger nodule volumes. This may explain the reported underestimation in nodule volume on non-contrast enhanced compared to contrast-enhanced acquisitions. • Pulmonary nodule volumes were measured on virtual non-contrast and mono-energetic reconstructions • Mono-energetic reconstructions showed that higher attenuation results in larger volumes • This may explain the reported nodule volume underestimation on non-contrast enhanced CT • Mostly metastatic pulmonary nodules were evaluated, results might differ for benign nodules.

Polar DuaLs of Convex Bodies

Science.gov (United States)

1990-01-01

dual mixed volumes are defined in Lutwak [181 by 17) (K,,....,K.) = 1 fp (K.,,u) ... p (K , u) du S.-’ where du signifies the area element on S". Let...the unit ball in R’. We shall use the following results of Lutwak [18]: (19) I’( )< ’ - ’" / and (20) V"(K 1,...,K.) _ VtK,).. V(K.). After obtaining...Rogers 161, Firey [91, Guggenheimer (13,141, Heil [161, Lutwak [18j, and Steinhardt [221 for partial results. In Theorem 3 we use an inequality due to

Adiabatic fast passage application in solid state NMR study of cross relaxation and molecular dynamics in heteronuclear systems.

Science.gov (United States)

Baranowski, M; Woźniak-Braszak, A; Jurga, K

2016-01-01

The paper presents the benefits of using fast adiabatic passage for the study of molecular dynamics in the solid state heteronuclear systems in the laboratory frame. A homemade pulse spectrometer operating at the frequency of 30.2MHz and 28.411MHz for protons and fluorines, respectively, has been enhanced with microcontroller direct digital synthesizer DDS controller [1-4]. This work briefly describes how to construct a low-cost and easy-to-assemble adiabatic extension set for homemade and commercial spectrometers based on recently very popular Arduino shields. The described set was designed for fast adiabatic generation. Timing and synchronization problems are discussed. The cross-relaxation experiments with different initial states of the two spin systems have been performed. Contrary to our previous work [5] where the steady-state NOE experiments were conducted now proton spins (1)H are polarized in the magnetic field B0 while fluorine spins (19)F are perturbed by selective saturation for a short time and then the system is allowed to evolve for a period in the absence of a saturating field. The adiabatic passage application leads to a reversal of magnetization of fluorine spins and increases the amplitude of the signal. Copyright © 2015 Elsevier Inc. All rights reserved.

Dual effect of insulin on plasma volume and transcapillary albumin transport

DEFF Research Database (Denmark)

Hilsted, J; Christensen, N J

1992-01-01

vascular dilatation and increased muscle sympathetic nerve activity during a euglycaemic glucose clamp. During similar conditions insulin increased the transcapillary escape rate of albumin and reduced plasma volume. Insulin has also an indirect effect on vascular permeability during hypoglycaemia, which...... is mediated by the increase in plasma adrenaline. Adrenaline infusion increased haematocrit and decreased plasma volume and intravascular albumin mass. In contrast to insulin adrenaline did not increase the transcapillary escape rate of albumin. Total autonomic blockade during insulin-induced hypoglycaemia...... abolished the increase in haematocrit, but did not influence the decrease in plasma volume and the increase in the transcapillary escape rate of albumin. Insulin administration may also increase urinary albumin excretion, and this effect was observed during a euglycaemic clamp. The mechanism of the increase...

Conservative and bounded volume-of-fluid advection on unstructured grids

Science.gov (United States)

Ivey, Christopher B.; Moin, Parviz

2017-12-01

This paper presents a novel Eulerian-Lagrangian piecewise-linear interface calculation (PLIC) volume-of-fluid (VOF) advection method, which is three-dimensional, unsplit, and discretely conservative and bounded. The approach is developed with reference to a collocated node-based finite-volume two-phase flow solver that utilizes the median-dual mesh constructed from non-convex polyhedra. The proposed advection algorithm satisfies conservation and boundedness of the liquid volume fraction irrespective of the underlying flux polyhedron geometry, which differs from contemporary unsplit VOF schemes that prescribe topologically complicated flux polyhedron geometries in efforts to satisfy conservation. Instead of prescribing complicated flux-polyhedron geometries, which are prone to topological failures, our VOF advection scheme, the non-intersecting flux polyhedron advection (NIFPA) method, builds the flux polyhedron iteratively such that its intersection with neighboring flux polyhedra, and any other unavailable volume, is empty and its total volume matches the calculated flux volume. During each iteration, a candidate nominal flux polyhedron is extruded using an iteration dependent scalar. The candidate is subsequently intersected with the volume guaranteed available to it at the time of the flux calculation to generate the candidate flux polyhedron. The difference in the volume of the candidate flux polyhedron and the actual flux volume is used to calculate extrusion during the next iteration. The choice in nominal flux polyhedron impacts the cost and accuracy of the scheme; however, it does not impact the methods underlying conservation and boundedness. As such, various robust nominal flux polyhedron are proposed and tested using canonical periodic kinematic test cases: Zalesak's disk and two- and three-dimensional deformation. The tests are conducted on the median duals of a quadrilateral and triangular primal mesh, in two-dimensions, and on the median duals of a

Stereoselective and stereospecific effects in the formation of heteronuclear tartrate complexes of 3d- and 4f-elements from proton magnetic relaxation data

International Nuclear Information System (INIS)

Sal'nikov, Yu.I.; Chevela, V.V.

1987-01-01

A new approach to identification of stereoselective and stereospecific effects in the formation of heteronuclear tartrate complexes of 3d- and 4f-elements according to proton magnetic relaxation data is developed. At the first stage comparison of experimental dependences of the property measured (relaxation efficiency coefficient, Bjerrum function etc.) on the consentrational parameters is conducted. Their different course in systems with dH 4 L (d-tartaric acid) and dlH 4 L (dl-tartaric acid) points out to the presence of stereoeffects. Then, using mathematical simulation the most true stoichiometry of complex particles is determined as well as optimized values of their stability constants and intensity factors. The method is used when investigating the following systems: Fe 3+ -dH 4 L(dlH 4 L), Ln 3+ -dH 4 L(dlH 4 L), Fe 3+ -Ln 3+ -dH 4 L(dlH 4 L)(Ln 3+ -Gd 3+ , Ho 3+ , Er 3+ , Tm 3+ )

Improved dose localization with dual energy photon irradiation in treatment of lateralized intracranial malignancies

International Nuclear Information System (INIS)

Cooley, G.; Gillin, M.T.; Murray, K.J.; Wilson, J.F.; Janjan, N.A.

1991-01-01

Dual energy photon irradiation (6 MV and 20 MV) was compared to conventional treatment planning with 6 MV photons in a lateralized intracranial malignancy. Dose volume analysis was performed of both the tumor plus a 2 cm margin (target volume, TV) and normal tissues (NT). Parallel opposed treatment using weightings of 1:1, 1.5:1, and 2:1 were compared for 6 MV photons alone or in combination with 20 MV photons. Uniform treatment of the TV was accomplished within the 60 Gy isodose. Significant differences were observed, however, in NT volumes receiving greater than or equal to 60 Gy and 45-59 Gy. Dual photon energy reduced treatment of NT volumes to greater than or equal to 60 Gy by 13% (177 cm3 vs 204 cm3 in 2:1 weighting) to 70% (147 cm3 vs 498 cm3 in 1:1 weighting) for comparable plans. Dose optimization was also performed for both 6 MV alone or in combination with 20 MV photons. Usual approaches to achieve dose lateralization with conventional isocentric techniques were applied including parallel opposed 6 MV photons ipsilaterally weighted 3.4:1 (POP), and a 110 degrees arc rotational field used to limit treatment to the eye (ARC). Dual energy photon optimized plans included a three beam parallel opposed plan (TOP) and a mixed photon ipsilateral (IPSI) approach. The technique using parallel opposed 20 MV photons and ipsilateral 6 MV photons (TOP) used beam weightings of 1.1 (contralateral 20 MVX): 1.6 (ipsilateral 6 MVX): 1 (ipsilateral 20 MVX) to achieve dose optimization. The ipsilateral approach with 6 MVX and 20 MVX (IPSI) used beam weightings of 1:1.4, respectively. All optimized plans demonstrated a 41% (120 cm3; POP) to 53% (95 cm3; TOP) improvement over parallel opposed 6 MV photons weighted 2:1 (204 cm3) in NT volume receiving greater than or equal to 60 Gy

Dual resolution cone beam breast CT: A feasibility study

International Nuclear Information System (INIS)

Chen Lingyun; Shen Youtao; Lai, Chao-Jen; Han Tao; Zhong Yuncheng; Ge Shuaiping; Liu Xinming; Wang Tianpeng; Yang, Wei T.; Whitman, Gary J.; Shaw, Chris C.

2009-01-01

Purpose: In this study, the authors investigated the feasibility of a dual resolution volume-of-interest (VOI) cone beam breast CT technique and compared two implementation approaches in terms of dose saving and scatter reduction. Methods: With this technique, a lead VOI mask with an opening is inserted between the x-ray source and the breast to deliver x-ray exposure to the VOI while blocking x rays outside the VOI. A CCD detector is used to collect the high resolution projection data of the VOI. Low resolution cone beam CT (CBCT) images of the entire breast, acquired with a flat panel (FP) detector, were used to calculate the projection data outside the VOI with the ray-tracing reprojection method. The Feldkamp-Davis-Kress filtered backprojection algorithm was used to reconstruct the dual resolution 3D images. Breast phantoms with 180 μm and smaller microcalcifications (MCs) were imaged with both FP and FP-CCD dual resolution CBCT systems, respectively. Two approaches of implementing the dual resolution technique, breast-centered approach and VOI-centered approach, were investigated and evaluated for dose saving and scatter reduction with Monte Carlo simulation using a GEANT4 package. Results: The results showed that the breast-centered approach saved more breast absorbed dose than did VOI-centered approach with similar scatter reduction. The MCs in fatty breast phantom, which were invisible with FP CBCT scan, became visible with the FP-CCD dual resolution CBCT scan. Conclusions: These results indicate potential improvement of the image quality inside the VOI with reduced breast dose both inside and outside the VOI.

Avoiding bias effects in NMR experiments for heteronuclear dipole-dipole coupling determinations: principles and application to organic semiconductor materials.

Science.gov (United States)

Kurz, Ricardo; Cobo, Marcio Fernando; de Azevedo, Eduardo Ribeiro; Sommer, Michael; Wicklein, André; Thelakkat, Mukundan; Hempel, Günter; Saalwächter, Kay

2013-09-16

Carbon-proton dipole-dipole couplings between bonded atoms represent a popular probe of molecular dynamics in soft materials or biomolecules. Their site-resolved determination, for example, by using the popular DIPSHIFT experiment, can be challenged by spectral overlap with nonbonded carbon atoms. The problem can be solved by using very short cross-polarization (CP) contact times, however, the measured modulation curves then deviate strongly from the theoretically predicted shape, which is caused by the dependence of the CP efficiency on the orientation of the CH vector, leading to an anisotropic magnetization distribution even for isotropic samples. Herein, we present a detailed demonstration and explanation of this problem, as well as providing a solution. We combine DIPSHIFT experiments with the rotor-directed exchange of orientations (RODEO) method, and modifications of it, to redistribute the magnetization and obtain undistorted modulation curves. Our strategy is general in that it can also be applied to other types of experiments for heteronuclear dipole-dipole coupling determinations that rely on dipolar polarization transfer. It is demonstrated with perylene-bisimide-based organic semiconductor materials, as an example, in which measurements of dynamic order parameters reveal correlations of the molecular dynamics with the phase structure and functional properties. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Dual axis radiographic hydrodynamic test facility. Final environmental impact statement, Volume 2: Public comments and responses

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-08-01

On May 12, 1995, the U.S. Department of Energy (DOE) issued the draft Dual Axis Radiographic Hydrodynamic Test Facility Environmental Impact Statement (DARHT EIS) for review by the State of New Mexico, Indian Tribes, local governments, other Federal agencies, and the general public. DOE invited comments on the accuracy and adequacy of the draft EIS and any other matters pertaining to their environmental reviews. The formal comment period ran for 45 days, to June 26, 1995, although DOE indicated that late comments would be considered to the extent possible. As part of the public comment process, DOE held two public hearings in Los Alamos and Santa Fe, New Mexico, on May 31 and June 1, 1995. In addition, DOE made the draft classified supplement to the DARHT EIS available for review by appropriately cleared individuals with a need to know the classified information. Reviewers of the classified material included the State of New Mexico, the U.S. Environmental Protection Agency, the Department of Defense, and certain Indian Tribes. Volume 2 of the final DARHT EIS contains three chapters. Chapter 1 includes a collective summary of the comments received and DOE`s response. Chapter 2 contains the full text of the public comments on the draft DARHT EIS received by DOE. Chapter 3 contains DOE`s responses to the public comments and an indication as to how the comments were considered in the final EIS.

Symptomatic burden of COPD for patients receiving dual or triple therapy

Directory of Open Access Journals (Sweden)

Chen S

2018-04-01

Full Text Available Stephanie Chen,1 Mark Small,2 Leandro Lindner,3 Xiao Xu1,4 1Health Economics and Payer Analytics, AstraZeneca, Gaithersburg, MD, USA; 2Respiratory, Adelphi Real World, Bollington, UK; 3Global Payer Evidence and Pricing, AstraZeneca, Cambridge, UK; 4Global Payer Evidence and Pricing, AstraZeneca, Gaithersburg, MD, USA Background: COPD is associated with a large disease burden. The use of dual (two maintenance treatments and triple (combination of any three treatments therapy has shown efficacy for symptom relief; however, some patients with COPD remain symptomatic despite these therapies. This study assessed the scope and magnitude of the symptomatic burden for patients with COPD receiving dual or triple therapy. Patients and methods: Cross-sectional data from three Adelphi COPD surveys (2013–2016 conducted in the USA, Europe, Japan, and China were analyzed for patients with COPD and forced expiratory volume in 1 second ≤65% receiving dual or triple therapy for ≥3 months. Physicians completed clinical and disease characteristic forms for identified patients. Corresponding patients completed questionnaires that included validated survey instruments to assess adherence and symptom impact. Descriptive statistics are reported. Results: Our analysis included 690 patients (mean age 68.2 years; 73.3% male; 41.4% and 58.6% were receiving dual and triple therapy, respectively. Most patients had dyspnea with substantial disability (modified Medical Research Council dyspnea scale rating ≥2, 56.3%; large health status impairment from symptoms, COPD Assessment Test score >20, 64.4%. A large symptom burden was observed, even for patients highly adherent to treatment (Morisky Medication Adherence Scale 8, 30.3% [185/612], of whom 62.1% still had a COPD Assessment Test score >20. Sensitivity analyses of patients regardless of their forced expiratory volume in 1 second status and of those receiving treatment for >6 months both reported similar results

Structural studies of the activation of the two component receiver domain NTRC by multidimensional heteronuclear NMR

Energy Technology Data Exchange (ETDEWEB)

Nohaile, Michael James [Univ. of California, Berkeley, CA (United States). Dept. of Chemistry

1996-05-01

Multidimensional heteronuclear NMR spectroscopy was used to investigate the N-terminal domain of the transcriptional enhancer NTRC (NiTrogen Regulatory protein C). This domain belongs to the family of receiver domains of two-component regulatory systems involved in signal transduction. Phosphorylation of NTRC at D54 leads to an activated form of the molecule which stimulates transcription of genes involved in nitrogen regulation. Three and four dimensional NMR techniques were used to determine an intermediate resolution structure of the unphosphorylated, inactive form of the N-terminal domain of NTRC. The structure is comprised of five α-helices and a five-stranded β-sheet in a (β/α)₅ topology. Analysis of the backbone dynamics of NTRC indicate that helix 4 and strand 5 are significantly more flexible than the rest of the secondary structure of the protein and that the loops making up the active site are flexible. The short lifetime of phospho-NTRC hampers the study of this form. However, conditions for determining the resonance assignments and, possibly, the three dimensional structure of phosphorylated NTRC have been obtained. Tentative assignments of the phosphorylated form indicate that the majority of the changes that NTRC experiences upon phosphorylation occur in helix 3, strand 4, helix 4, strand 5, and the loop between strand 5 and helix 5 (the 3445 face of NTRC) as well as near the site of phosphorylation. In order to examine a stable, activated form of the protein, constitutively active mutants of NTRC were investigated.

Dual-mode plasmonic nanorod type antenna based on the concept of a trapped dipole.

Science.gov (United States)

Panaretos, Anastasios H; Werner, Douglas H

2015-04-06

In this paper we theoretically investigate the feasibility of creating a dual-mode plasmonic nanorod antenna. The proposed design methodology relies on adapting to optical wavelengths the principles of operation of trapped dipole antennas, which have been widely used in the low MHz frequency range. This type of antenna typically employs parallel LC circuits, also referred to as "traps", which are connected along the two arms of the dipole. By judiciously choosing the resonant frequency of these traps, as well as their position along the arms of the dipole, it is feasible to excite the λ/2 resonance of both the original dipole as well as the shorter section defined by the length of wire between the two traps. This effectively enables the dipole antenna to have a dual-mode of operation. Our analysis reveals that the implementation of this concept at the nanoscale requires that two cylindrical pockets (i.e. loading volumes) be introduced along the length of the nanoantenna, inside which plasmonic core-shell particles are embedded. By properly selecting the geometry and constitution of the core-shell particle as well as the constitution of the host material of the two loading volumes and their position along the nanorod, the equivalent effect of a resonant parallel LC circuit can be realized. This effectively enables a dual-mode operation of the nanorod antenna. The proposed methodology introduces a compact approach for the realization of dual-mode optical sensors while at the same time it clearly illustrates the inherent tuning capabilities that core-shell particles can offer in a practical framework.

The Stiffness and Damping Characteristics of a Dual-Chamber Air Spring Device Applied to Motion Suppression of Marine Structures

Directory of Open Access Journals (Sweden)

Xiaohui Zeng

2016-03-01

Full Text Available Dual-chamber air springs are used as a key component for vibration isolation in some industrial applications. The working principle of the dual-chamber air spring device as applied to motion suppression of marine structures is similar to that of the traditional air spring, but they differ in their specific characteristics. The stiffness and damping of the dual-chamber air spring device determine the extent of motion suppression. In this article, we investigate the stiffness and damping characteristics of a dual-chamber air spring device applied to marine structure motion suppression using orthogonal analysis and an experimental method. We measure the effects of volume ratio, orifice ratio, excitation amplitude, and frequency on the stiffness and damping of the dual-chamber vibration absorber. Based on the experimental results, a higher-order non-linear regression method is obtained. We achieve a rapid calculation model for dual-chamber air spring stiffness and damping, which can provide guidance to project design.

Vegetation Parameter Extraction Using Dual Baseline Polarimetric SAR Interferometry Data

Science.gov (United States)

Zhang, H.; Wang, C.; Chen, X.; Tang, Y.

2009-04-01

For vegetation parameter inversion, the single baseline polarimetric SAR interferometry (POLinSAR) technique, such as the three-stage method and the ESPRIT algorithm, is limited by the observed data with the minimum ground to volume amplitude ration, which effects the estimation of the effective phase center for the vegetation canopy or the surface, and thus results in the underestimated vegetation height. In order to remove this effect of the single baseline inversion techniques in some extend, another baseline POLinSAR data is added on vegetation parameter estimation in this paper, and a dual baseline POLinSAR technique for the extraction of the vegetation parameter is investigated and improved to reduce the dynamic bias for the vegetation parameter estimation. Finally, the simulated data and real data are used to validate this dual baseline technique.

Simple Heat Treatment for Production of Hot-Dip Galvanized Dual Phase Steel Using Si-Al Steels

Science.gov (United States)

Equihua-Guillén, F.; García-Lara, A. M.; Muñíz-Valdes, C. R.; Ortíz-Cuellar, J. C.; Camporredondo-Saucedo, J. E.

2014-01-01

This work presents relevant metallurgical considerations to produce galvanized dual phase steels from low cost aluminum-silicon steels which are produced by continuous strip processing. Two steels with different contents of Si and Al were austenized in the two-phase field ferrite + austenite (α + γ) in a fast manner to obtain dual phase steels, suitable for hot-dip galvanizing process, under typical parameters of continuous annealing processing line. Tensile dual phase properties were obtained from specimens cooled from temperature below Ar3, held during 3 min, intermediate cooling at temperature above Ar1 and quenching in Zn bath at 465 °C. The results have shown typical microstructure and tensile properties of galvanized dual phase steels. Finally, the synergistic effect of aluminum, silicon, and residual chromium on martensite start temperature ( M s), critical cooling rate ( C R), volume fraction of martensite, and tensile properties has been studied.

Automatic exposure control at single- and dual-heartbeat CTCA on a 320-MDCT volume scanner: effect of heart rate, exposure phase window setting, and reconstruction algorithm.

Science.gov (United States)

Funama, Yoshinori; Utsunomiya, Daisuke; Taguchi, Katsuyuki; Oda, Seitaro; Shimonobo, Toshiaki; Yamashita, Yasuyuki

2014-05-01

To investigate whether electrocardiogram (ECG)-gated single- and dual-heartbeat computed tomography coronary angiography (CTCA) with automatic exposure control (AEC) yields images with uniform image noise at reduced radiation doses. Using an anthropomorphic chest CT phantom we performed prospectively ECG-gated single- and dual-heartbeat CTCA on a second-generation 320-multidetector CT volume scanner. The exposure phase window was set at 75%, 70-80%, 40-80%, and 0-100% and the heart rate at 60 or 80 or corr80 bpm; images were reconstructed with filtered back projection (FBP) or iterative reconstruction (IR, adaptive iterative dose reduction 3D). We applied AEC and set the image noise level to 20 or 25 HU. For each technique we determined the image noise and the radiation dose to the phantom center. With half-scan reconstruction at 60 bpm, a 70-80% phase window- and a 20-HU standard deviation (SD) setting, the imagenoise level and -variation along the z axis manifested similar curves with FBP and IR. With half-scan reconstruction, the radiation dose to the phantom center with 70-80% phase window was 18.89 and 12.34 mGy for FBP and 4.61 and 3.10 mGy for IR at an SD setting SD of 20 and 25 HU, respectively. At 80 bpm with two-segment reconstruction the dose was approximately twice that of 60 bpm at both SD settings. However, increasing radiation dose at corr80 bpm was suppressed to 1.39 times compared to 60 bpm. AEC at ECG-gated single- and dual-heartbeat CTCA controls the image noise at different radiation dose. Copyright © 2013 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Self-dual Hopf quivers

International Nuclear Information System (INIS)

Huang Hualin; Li Libin; Ye Yu

2004-07-01

We study pointed graded self-dual Hopf algebras with a help of the dual Gabriel theorem for pointed Hopf algebras. Quivers of such Hopf algebras are said to be self-dual. An explicit classification of self-dual Hopf quivers is obtained. We also prove that finite dimensional coradically graded pointed self-dual Hopf algebras are generated by group-like and skew-primitive elements as associative algebras. This partially justifies a conjecture of Andruskiewitsch and Schneider and may help to classify finite dimensional self-dual pointed Hopf algebras

Novel multi-dimensional heteronuclear NMR techniques for the study of 13C-O-acetylated oligosaccharides: Expanding the dimensions for carbohydrate structures

Energy Technology Data Exchange (ETDEWEB)

Jones, David N.M. [University of Colorado Health Sciences Center, Departments of Pharmacology (United States); Bendiak, Brad [University of Colorado Health Sciences Center, Departments of Cellular and Structural Biology (United States)

1999-10-15

Complex carbohydrates have critical roles in a wide variety of biological processes. An understanding of the molecular mechanisms that underlie these processes is essential in the development of novel oligosaccharide-based therapeutic strategies. Unfortunately, obtaining detailed structural information for larger oligosaccharides (>10 residues) can be exceedingly difficult, especially where the amount of sample available is limited. Here we demonstrate the application of {sup 13} C O-acetylation in combination with novel NMR experiments to obtain much of the information required to characterize the primary structure of oligosaccharides. (H)C{sub Me}COH-HEHAHA and H(C{sub Me})COH-HEHAHA experiments are presented that use heteronuclear Hartmann-Hahn transfer to correlate the acetyl groups with sugar ring protons in peracetylated oligosaccharides. The in-phase, pure absorption nature of the correlation peaks in these experiments allows measurement of both chemical shifts and, importantly, {sup 1}H-{sup 1}H coupling constants that are used to define the stereochemistry of the sugar ring. The (HC{sub Me})COH and (HC{sub Me})COH-RELAY experiments provide additional methods for obtaining chemical shift assignments for larger oligosaccharides to define the sites of glycosidic linkages from the patterns of acetylation.

Dual Youla parameterization

DEFF Research Database (Denmark)

Niemann, Hans Henrik

2003-01-01

A different aspect of using the parameterisation of all systems stabilised by a given controller, i.e. the dual Youla parameterisation, is considered. The relation between system change and the dual Youla parameter is derived in explicit form. A number of standard uncertain model descriptions...... are considered and the relation with the dual Youla parameter given. Some applications of the dual Youla parameterisation are considered in connection with the design of controllers and model/performance validation....

Dual Smarandache Curves of a Timelike Curve lying on Unit dual Lorentzian Sphere

OpenAIRE

Kahraman, Tanju; Hüseyin Ugurlu, Hasan

2016-01-01

In this paper, we give Darboux approximation for dual Smarandache curves of time like curve on unit dual Lorentzian sphere. Firstly, we define the four types of dual Smarandache curves of a timelike curve lying on dual Lorentzian sphere.

Dual-Use Space Technology Transfer Conference and Exhibition. Volume 1

Science.gov (United States)

Krishen, Kumar (Compiler)

1994-01-01

This document contains papers presented at the Dual-Use Space Technology Transfer Conference and Exhibition held at the Johnson Space Center February 1-3, 1994. Possible technology transfers covered during the conference were in the areas of information access; innovative microwave and optical applications; materials and structures; marketing and barriers; intelligent systems; human factors and habitation; communications and data systems; business process and technology transfer; software engineering; biotechnology and advanced bioinstrumentation; communications signal processing and analysis; new ways of doing business; medical care; applications derived from control center data systems; human performance evaluation; technology transfer methods; mathematics, modeling, and simulation; propulsion; software analysis and decision tools systems/processes in human support technology; networks, control centers, and distributed systems; power; rapid development perception and vision technologies; integrated vehicle health management; automation technologies; advanced avionics; ans robotics technologies. More than 77 papers, 20 presentations, and 20 exhibits covering various disciplines were presented b experts from NASA, universities, and industry.

Reliable Dual Tensor Model Estimation in Single and Crossing Fibers Based on Jeffreys Prior

Science.gov (United States)

Yang, Jianfei; Poot, Dirk H. J.; Caan, Matthan W. A.; Su, Tanja; Majoie, Charles B. L. M.; van Vliet, Lucas J.; Vos, Frans M.

2016-01-01

Purpose This paper presents and studies a framework for reliable modeling of diffusion MRI using a data-acquisition adaptive prior. Methods Automated relevance determination estimates the mean of the posterior distribution of a rank-2 dual tensor model exploiting Jeffreys prior (JARD). This data-acquisition prior is based on the Fisher information matrix and enables the assessment whether two tensors are mandatory to describe the data. The method is compared to Maximum Likelihood Estimation (MLE) of the dual tensor model and to FSL’s ball-and-stick approach. Results Monte Carlo experiments demonstrated that JARD’s volume fractions correlated well with the ground truth for single and crossing fiber configurations. In single fiber configurations JARD automatically reduced the volume fraction of one compartment to (almost) zero. The variance in fractional anisotropy (FA) of the main tensor component was thereby reduced compared to MLE. JARD and MLE gave a comparable outcome in data simulating crossing fibers. On brain data, JARD yielded a smaller spread in FA along the corpus callosum compared to MLE. Tract-based spatial statistics demonstrated a higher sensitivity in detecting age-related white matter atrophy using JARD compared to both MLE and the ball-and-stick approach. Conclusions The proposed framework offers accurate and precise estimation of diffusion properties in single and dual fiber regions. PMID:27760166

Potassium-Based Dual Ion Battery with Dual-Graphite Electrode.

Science.gov (United States)

Fan, Ling; Liu, Qian; Chen, Suhua; Lin, Kairui; Xu, Zhi; Lu, Bingan

2017-08-01

A potassium ion battery has potential applications for large scale electric energy storage systems due to the abundance and low cost of potassium resources. Dual graphite batteries, with graphite as both anode and cathode, eliminate the use of transition metal compounds and greatly lower the overall cost. Herein, combining the merits of the potassium ion battery and dual graphite battery, a potassium-based dual ion battery with dual-graphite electrode is developed. It delivers a reversible capacity of 62 mA h g -1 and medium discharge voltage of ≈3.96 V. The intercalation/deintercalation mechanism of K + and PF 6 - into/from graphite is proposed and discussed in detail, with various characterizations to support. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Dual vector multiplet coupled to dual N=1 supergravity in 10D

International Nuclear Information System (INIS)

Nishino, Hitoshi; Rajpoot, Subhash

2005-01-01

We couple in superspace a dual vector multiplet (C m 1 ...m 7 ,λ α ) to the dual version of N=1 supergravity (e m a ,ψ m α ,M m 1 ...m 6 ,χ α ,Φ) in ten dimensions. The 7-form field C has its 8-form field strength H dual to the 2-form field strength F of the conventional vector multiplet. To simplify the computation, we use so-called beta-function-favored superspace constraints for dual supergravity developed for β-function computations. As in a more conventional constraint set, the H-Bianchi identity must have the form N and F, where N is the 7-form field strength in dual supergravity. The potential anomaly for the dual vector multiplet can be cancelled for the particular gauge group U(1) 496 by the Green-Schwarz mechanism. As a by-product, we also give the globally supersymmetric Abelian Dirac-Born-Infeld interactions for the dual vector multiplet for the first time

On volumes of subregions in holography and complexity

Energy Technology Data Exchange (ETDEWEB)

Ben-Ami, Omer [Raymond and Beverly Sackler Faculty of Exact Sciences School of Physics and Astronomy,Tel-Aviv University, Ramat-Aviv, 69978 (Israel); Carmi, Dean [Raymond and Beverly Sackler Faculty of Exact Sciences School of Physics and Astronomy,Tel-Aviv University, Ramat-Aviv, 69978 (Israel); Perimeter Institute for Theoretical Physics,31 Caroline Street North, ON, N2L 2Y5 (Canada)

2016-11-22

The volume of the region inside the bulk Ryu-Takayanagi surface is a codimension-one object, and a natural generalization of holographic complexity to the case of subregions in the boundary QFT. We focus on time-independent geometries, and study the properties of this volume in various circumstances. We derive a formula for computing the volume for a strip entangling surface and a general asymptotically AdS bulk geometry. For an AdS black hole geometry, the volume exhibits non-monotonic behaviour as a function of the size of the entangling region (unlike the behaviour of the entanglement entropy in this setup, which is monotonic). For setups in which the holographic entanglement entropy exhibits transitions in the bulk, such as global AdS black hole, geometries dual to confining theories and disjoint entangling surfaces, the corresponding volume exhibits a discontinuous finite jump at the transition point (and so do the volumes of the corresponding entanglement wedges). We compute this volume discontinuity in several examples. Lastly, we compute the codim-zero volume and the bulk action of the entanglement wedge for the case of a sphere entangling surface and pure AdS geometry.

Deep white matter hyperintensities, microstructural integrity and dual task walking in older people.

Science.gov (United States)

Ghanavati, Tabassom; Smitt, Myriam Sillevis; Lord, Stephen R; Sachdev, Perminder; Wen, Wei; Kochan, Nicole A; Brodaty, Henry; Delbaere, Kim

2018-01-03

To examine neural, physiological and cognitive influences on gait speed under single and dual-task conditions. Sixty-two community-dwelling older people (aged 80.0 ± 4.2 years) participated in our study. Gait speed was assessed with a timed 20-meter walk under single and dual-task (reciting alternate letters of the alphabet) conditions. Participants also underwent tests to estimate physiological fall risk based on five measures of sensorimotor function, cognitive function across five domains, brain white matter (WM) hyperintensities and WM microstructural integrity by measuring fractional anisotropy (FA). Univariate linear regression analyses showed that global physiological and cognitive measures were associated with single (β = 0.594 and β=-0.297, respectively) and dual-task gait speed (β = 0.306 and β=-0.362, respectively). Deep WMHs were associated with dual-task gait speed only (β = 0.257). Multivariate mediational analyses showed that global and executive cognition reduced the strength of the association between deep WMHs and dual-task gait speed by 27% (β = 0.188) and 44% (β = 0.145) respectively. There was a significant linear association between single-task gait speed and mean FA values of the genu (β=-0.295) and splenium (β=-0.326) of the corpus callosum, and between dual-task gait speed and mean FA values of Superior Cerebellar Peduncle (β=-0.284), splenium of the Corpus Callosum (β=-0.286) and Cingulum (β=-0.351). Greater deep WMH volumes are associated with slower walking speed under dual-task conditions, and this relationship is mediated in part by global cognition and executive abilities specifically. Furthermore, both cerebellum and cingulum are related to dual-task walking due to their role in motor skill performance and attention, respectively.

Influence of vascular enhancement, age and gender on pulmonary perfused blood volume quantified by dual-energy-CTPA

International Nuclear Information System (INIS)

Meinel, Felix G.; Graef, Anita; Sommer, Wieland H.; Thierfelder, Kolja M.; Reiser, Maximilian F.; Johnson, Thorsten R.C.

2013-01-01

Objectives: To determine the influence of technical and demographic parameters on quantification of pulmonary perfused blood volume (PBV) in dual energy computed tomography pulmonary angiography (DE-CTPA). Materials and methods: Pulmonary PBV was quantified in 142 patients who underwent DE-CTPA for suspected pulmonary embolism but in whom no thoracic pathologies were detected. Multivariate linear regression analysis was performed to calculate the influence of age, gender, enhancement of pulmonary trunk and enhancement difference between pulmonary trunk and left atrium (as a measure of timing) on PBV values. The resulting regression coefficients were used to calculate age-specific ranges of normal for PBV values adjusted for vascular enhancement and timing. Results: Enhancement of the pulmonary trunk (β = −0.29, p = 0.001) and enhancement difference between pulmonary trunk and left atrium (β = −0.24, p = 0.003) were found to significantly influence PBV values. Age (β = −0.33, p < 0.001) but not gender (β = 0.14, p = 0.05) had a significant negative influence on pulmonary PBV values. There was a 20% relative decrease of pulmonary PBV from patients aged <30 to patients over 80 years of age. Conclusions: DE-CTPA derived PBV values need to be corrected for age, vascular enhancement and timing but not for gender. The age-specific ranges of normal derived from this study can be used as a reference in future studies of PBV in pulmonary pathologies

Reference Values for Assessment of Unilateral Limb Lymphedema with Dual-Energy X-Ray Absorptiometry

DEFF Research Database (Denmark)

Gjorup, Caroline A; Hendel, Helle W; Klausen, Tobias W

2018-01-01

INTRODUCTION: The clinical assessment of unilateral limb lymphedema is commonly based on measurements of interlimb volume differences. Reference values for interlimb percentage differences of the volume, fat mass, and lean mass measured with dual-energy X-ray absorptiometry (DXA) scan are, however...... is calculated as follows: ("Limb-of-interest"-contralateral)/contralateral × 100. The interlimb percentage differences for the limb-of-interest were stratified to upper (according to handedness) and lower limbs and categorized as none/mild, moderate, or severe, respectively, based on whether the value is below...

Dual-energy perfusion-CT in recurrent pancreatic cancer. Preliminary results

Energy Technology Data Exchange (ETDEWEB)

Fritz, F.; Skornitzke, S.; Kauczor, H.U.; Stiller, W.; Klauss, M. [Heidelberg Univ. (Germany). Clinic of Diagnostic and Interventional Radiology; Hackert, T. [Heidelberg Univ. (Germany). Clinic of Surgery; Grenacher, L. [Diagnostik Muenchen (Germany). Diagnostic Imaging Center

2016-06-15

To evaluate the diagnostic performance of dual energy (DE) perfusion-CT for the differentiation between postoperative soft-tissue formation and tumor recurrence in patients after potentially curative pancreatic cancer resection. 24 patients with postoperative soft-tissue formation in the conventional regular follow-up CT acquisition after pancreatic cancer resection with curative intent were included prospectively. They were examined with a 64-row dual-source CT using a dynamic sequence of 34 DE acquisitions every 1.5 s (80 ml of iodinated contrast material, 370 mg/ml, flow rate 5 ml/s). Weighted average (linearly blended M0.5) 120 kVp-equivalent dual-energy perfusion image data sets were evaluated with a body-perfusion CT tool for estimating blood flow, permeability, and blood volume. Diagnosis was confirmed by histological study (n=4) and by regular follow-up. Final diagnosis was local recurrence of pancreatic cancer in 15 patients and unspecific postoperative tissue formation in 9 patients. The blood-flow values for recurrence tissue trended to be lower compared to postoperative tissue formation with 16.6 ml/100 ml/min and 24.7 ml/100 ml/min, respectively for weighted average 120 kVp-equivalent image data, which was not significant (n.s.) (p=0.06, significance level 0.05). Permeability- and blood-volume values were only slightly lower in recurrence tissue (n.s.). DE perfusion-CT is feasible in patients after pancreatic cancer resection and a promising functional imaging technique. As only a trend for lower perfusion values in local recurrence compared to unspecific postoperative alterations was found, the perfusion differences are not yet sufficient to differentiate between malignancy and unspecific postoperative alterations for this new technique. Further studies and technical improvements are needed to generate reliable data for this clinically highly relevant differentiation.

Nanocavity formation and hardness increase by dual ion beam irradiation of oxide dispersion strengthened FeCrAl alloy

Energy Technology Data Exchange (ETDEWEB)

Koegler, R., E-mail: r.koegler@hzdr.de [Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstrasse 400, 01328 Dresden (Germany); Anwand, W. [Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstrasse 400, 01328 Dresden (Germany); Richter, A. [Department of Engineering, Technical University of Applied Sciences Wildau, Bahnhofstrasse 1, 15745 Wildau (Germany); Butterling, M.; Ou, Xin; Wagner, A. [Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstrasse 400, 01328 Dresden (Germany); Chen, C.-L. [Department of Materials Science and Engineering, I-Shou University, Kaohsiung 840, Taiwan (China)

2012-08-15

Open volume defects generated by ion implantation into oxide dispersion strengthened (ODS) alloy and the related hardness were investigated by positron annihilation spectroscopy and nanoindentation measurements, respectively. Synchronized dual beam implantation of Fe and He ions was performed at room temperature and at moderately enhanced temperature of 300 Degree-Sign C. For room temperature implantation a significant hardness increase after irradiation is observed which is more distinctive in heat treated than in as-received ODS alloy. There is also a difference between the simultaneous and sequential implantation mode as the hardening effect for the simultaneously implanted ODS alloy is stronger than for sequential implantation. The comparison of hardness profiles and of the corresponding open volume profiles shows a qualitative agreement between the open volume defects generated on the nanoscopic scale and the macroscopic hardness characteristics. Open volume defects are drastically reduced for performing the simultaneous dual beam irradiation at 300 Degree-Sign C which is a more realistic temperature under application aspects. Few remaining defects are clusters of 3-4 vacancies in connection with Y oxide nanoparticles. These defects completely disappear in a shallow layer at the surface. The results are in agreement with hardness measurements showing little hardness increase after irradiation at 300 Degree-Sign C. Suitable characteristics of ODS alloy for nuclear applications and the close correlation between He-related open volume defects and the hardness characteristics are verified.

Dual Income Taxes

DEFF Research Database (Denmark)

Sørensen, Peter Birch

This paper discusses the principles and practices of dual income taxation in the Nordic countries. The first part of the paper explains the rationale and the historical background for the introduction of the dual income tax and describes the current Nordic tax practices. The second part...... of the paper focuses on the problems of taxing income from small businesses and the issue of corporate-personal tax integration under the dual income tax, considering alternative ways of dealing with these challenges. In the third and final part of the paper, I briefly discuss whether introducing a dual income...

Dual Diagnosis - Multiple Languages

Science.gov (United States)

... National Library of Medicine Comorbidity or dual diagnosis - Opioid addiction, part 9 - English PDF Comorbidity or dual diagnosis - Opioid addiction, part 9 - español (Spanish) PDF Comorbidity or dual ...

A combined finite volume-nonconforming finite element scheme for compressible two phase flow in porous media

KAUST Repository

Saad, Bilal Mohammed; Saad, Mazen Naufal B M

2014-01-01

We propose and analyze a combined finite volume-nonconforming finite element scheme on general meshes to simulate the two compressible phase flow in porous media. The diffusion term, which can be anisotropic and heterogeneous, is discretized by piecewise linear nonconforming triangular finite elements. The other terms are discretized by means of a cell-centered finite volume scheme on a dual mesh, where the dual volumes are constructed around the sides of the original mesh. The relative permeability of each phase is decentred according the sign of the velocity at the dual interface. This technique also ensures the validity of the discrete maximum principle for the saturation under a non restrictive shape regularity of the space mesh and the positiveness of all transmissibilities. Next, a priori estimates on the pressures and a function of the saturation that denote capillary terms are established. These stabilities results lead to some compactness arguments based on the use of the Kolmogorov compactness theorem, and allow us to derive the convergence of a subsequence of the sequence of approximate solutions to a weak solution of the continuous equations, provided the mesh size tends to zero. The proof is given for the complete system when the density of the each phase depends on its own pressure. © 2014 Springer-Verlag Berlin Heidelberg.

A combined finite volume-nonconforming finite element scheme for compressible two phase flow in porous media

KAUST Repository

Saad, Bilal Mohammed

2014-06-28

We propose and analyze a combined finite volume-nonconforming finite element scheme on general meshes to simulate the two compressible phase flow in porous media. The diffusion term, which can be anisotropic and heterogeneous, is discretized by piecewise linear nonconforming triangular finite elements. The other terms are discretized by means of a cell-centered finite volume scheme on a dual mesh, where the dual volumes are constructed around the sides of the original mesh. The relative permeability of each phase is decentred according the sign of the velocity at the dual interface. This technique also ensures the validity of the discrete maximum principle for the saturation under a non restrictive shape regularity of the space mesh and the positiveness of all transmissibilities. Next, a priori estimates on the pressures and a function of the saturation that denote capillary terms are established. These stabilities results lead to some compactness arguments based on the use of the Kolmogorov compactness theorem, and allow us to derive the convergence of a subsequence of the sequence of approximate solutions to a weak solution of the continuous equations, provided the mesh size tends to zero. The proof is given for the complete system when the density of the each phase depends on its own pressure. © 2014 Springer-Verlag Berlin Heidelberg.

Self-dual metrics with self-dual Killing vectors

International Nuclear Information System (INIS)

Tod, K.P.; Ward, R.S.

1979-01-01

Twistor methods are used to derive a class of solutions to Einstein's vacuum equations, with anti-self dual Weyl tensor. In particular, all metrics with a Killing vector whose derivative is anti-self-dual and which admit a real positive-definite section are exhibited and shown to coincide with the metrics of Hawking. (author)

Dual multispectral and 3D structured light laparoscope

Science.gov (United States)

Clancy, Neil T.; Lin, Jianyu; Arya, Shobhit; Hanna, George B.; Elson, Daniel S.

2015-03-01

Intraoperative feedback on tissue function, such as blood volume and oxygenation would be useful to the surgeon in cases where current clinical practice relies on subjective measures, such as identification of ischaemic bowel or tissue viability during anastomosis formation. Also, tissue surface profiling may be used to detect and identify certain pathologies, as well as diagnosing aspects of tissue health such as gut motility. In this paper a dual modality laparoscopic system is presented that combines multispectral reflectance and 3D surface imaging. White light illumination from a xenon source is detected by a laparoscope-mounted fast filter wheel camera to assemble a multispectral image (MSI) cube. Surface shape is then calculated using a spectrally-encoded structured light (SL) pattern detected by the same camera and triangulated using an active stereo technique. Images of porcine small bowel were acquired during open surgery. Tissue reflectance spectra were acquired and blood volume was calculated at each spatial pixel across the bowel wall and mesentery. SL features were segmented and identified using a `normalised cut' algoritm and the colour vector of each spot. Using the 3D geometry defined by the camera coordinate system the multispectral data could be overlaid onto the surface mesh. Dual MSI and SL imaging has the potential to provide augmented views to the surgeon supplying diagnostic information related to blood supply health and organ function. Future work on this system will include filter optimisation to reduce noise in tissue optical property measurement, and minimise spot identification errors in the SL pattern.

Pulmonary Perfusion Changes as Assessed by Contrast-Enhanced Dual-Energy Computed Tomography after Endoscopic Lung Volume Reduction by Coils.

Science.gov (United States)

Lador, Frédéric; Hachulla, Anne-Lise; Hohn, Olivia; Plojoux, Jérôme; Ronot, Maxime; Montet, Xavier; Soccal, Paola M

2016-01-01

Endoscopic lung volume reduction by coils (LVRC) is a recent treatment approach for severe emphysema. Furthermore, dual-energy computed tomography (DECT) now offers a combined assessment of lung morphology and pulmonary perfusion. The aim of our study was to assess the impact of LVRC on pulmonary perfusion with DECT. Seventeen patients (64.8 ± 6.7 years) underwent LVRC. DECT was performed prior to and after LVRC. For each patient, lung volumes and emphysema quantification were automatically calculated. Then, 6 regions of interest (ROIs) on the iodine perfusion map were drawn in the anterior, mid, and posterior right and left lungs at 4 defined levels. The ROI values were averaged to obtain lung perfusion as assessed by the lung's iodine concentration (CLung, μg·cm-3). The CLung values were normalized using the left atrial iodine concentration (CLA) to take into account differences between successive DECT scans. The 6-min walk distance (6MWD) improved significantly after the procedure (p = 0.0002). No lung volume changes were observed between successive DECT scans for any of the patients (p = 0.32), attesting the same suspended inspiration. After LVRC, the emphysema index was significantly reduced in the treated lung (p = 0.0014). Lung perfusion increased significantly adjacent to the treated areas (CLung/CLA from 3.4 ± 1.7 to 5.6 ± 2.2, p < 0.001) and in the ipsilateral untreated areas (from 4.1 ± 1.4 to 6.6 ± 1.7, p < 0.001), corresponding to a mean 65 and 61% increase in perfusion, respectively. No significant difference was observed in the contralateral upper and lower areas (from 4.4 ± 1.9 to 4.8 ± 2.1, p = 0.273, and from 4.9 ± 2.0 to 5.2 ± 1.7, p = 0.412, respectively). A significant correlation between increased 6MWD and increased perfusion was found (p = 0.0027, R2 = 0.3850). Quantitative analysis based on DECT acquisition revealed that LVRC results in a significant increase in perfusion in the coil-free areas adjacent to the treated ones, as

Investigation of a tubular dual-stator flux-switching permanent-magnet linear generator for free-piston energy converter

Science.gov (United States)

Sui, Yi; Zheng, Ping; Tong, Chengde; Yu, Bin; Zhu, Shaohong; Zhu, Jianguo

2015-05-01

This paper describes a tubular dual-stator flux-switching permanent-magnet (PM) linear generator for free-piston energy converter. The operating principle, topology, and design considerations of the machine are investigated. Combining the motion characteristic of free-piston Stirling engine, a tubular dual-stator PM linear generator is designed by finite element method. Some major structural parameters, such as the outer and inner radii of the mover, PM thickness, mover tooth width, tooth width of the outer and inner stators, etc., are optimized to improve the machine performances like thrust capability and power density. In comparison with conventional single-stator PM machines like moving-magnet linear machine and flux-switching linear machine, the proposed dual-stator flux-switching PM machine shows advantages in higher mass power density, higher volume power density, and lighter mover.

Dual affine isoperimetric inequalities

Directory of Open Access Journals (Sweden)

Bin Xiong

2006-01-01

Full Text Available We establish some inequalities for the dual -centroid bodies which are the dual forms of the results by Lutwak, Yang, and Zhang. Further, we establish a Brunn-Minkowski-type inequality for the polar of dual -centroid bodies.

Inner volume leakage during integrated leakage rate testing

International Nuclear Information System (INIS)

Glover, J.P.

1987-01-01

During an integrated leak rate test (ILRT), the containment structure is maintained at test pressure with most penetrations isolated. Since penetrations typically employ dual isolation, the possibility exists for the inner isolation to leak while the outer holds. In this case, the ILRT instrumentation system would indicate containment out-leakage when, in fact, only the inner volume between closures is being pressurized. The problem is compounded because this false leakage is not readily observable outside of containment by standard leak inspection techniques. The inner volume leakage eventually subsides after the affected volumes reach test pressure. Depending on the magnitude of leakage and the size of the volumes, equalization could occur prior to the end of the pretest stabilization period, or significant false leakages may persist throughout the entire test. Two simple analyses were performed to quantify the effects of inside volume leakages. First, a lower bound for the equalization time was found. A second analysis was performed to find an approximate upper bound for the stabilization time. The results of both analyses are shown

A dual porosity model of nutrient uptake by root hairs

KAUST Repository

Zygalakis, K. C.; Kirk, G. J. D.; Jones, D. L.; Wissuwa, M.; Roose, T.

2011-01-01

Summary: • The importance of root hairs in the uptake of sparingly soluble nutrients is understood qualitatively, but not quantitatively, and this limits efforts to breed plants tolerant of nutrient-deficient soils. • Here, we develop a mathematical model of nutrient uptake by root hairs allowing for hair geometry and the details of nutrient transport through soil, including diffusion within and between soil particles. We give illustrative results for phosphate uptake. • Compared with conventional 'single porosity' models, this 'dual porosity' model predicts greater root uptake because more nutrient is available by slow release from within soil particles. Also the effect of soil moisture is less important with the dual porosity model because the effective volume available for diffusion in the soil is larger, and the predicted effects of hair length and density are different. • Consistent with experimental observations, with the dual porosity model, increases in hair length give greater increases in uptake than increases in hair density per unit main root length. The effect of hair density is less in dry soil because the minimum concentration in solution for net influx is reached more rapidly. The effect of hair length is much less sensitive to soil moisture. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

A dual porosity model of nutrient uptake by root hairs

KAUST Repository

Zygalakis, K. C.

2011-08-09

Summary: • The importance of root hairs in the uptake of sparingly soluble nutrients is understood qualitatively, but not quantitatively, and this limits efforts to breed plants tolerant of nutrient-deficient soils. • Here, we develop a mathematical model of nutrient uptake by root hairs allowing for hair geometry and the details of nutrient transport through soil, including diffusion within and between soil particles. We give illustrative results for phosphate uptake. • Compared with conventional \\'single porosity\\' models, this \\'dual porosity\\' model predicts greater root uptake because more nutrient is available by slow release from within soil particles. Also the effect of soil moisture is less important with the dual porosity model because the effective volume available for diffusion in the soil is larger, and the predicted effects of hair length and density are different. • Consistent with experimental observations, with the dual porosity model, increases in hair length give greater increases in uptake than increases in hair density per unit main root length. The effect of hair density is less in dry soil because the minimum concentration in solution for net influx is reached more rapidly. The effect of hair length is much less sensitive to soil moisture. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

Initial experience with visualizing hand and foot tendons by dual-energy computed tomography.

Science.gov (United States)

Deng, Kai; Sun, Cong; Liu, Cheng; Ma, Rui

2009-01-01

To assess the feasibility of visualizing hand and foot tendons by dual-energy computed tomography (CT). Twenty patients who suffered from hand or feet pains were scanned on dual-source CT (Definition, Forchheim, Germany) with dual-energy mode at tube voltages of 140 and 80 kV and a corresponding ratio of 1:4 between tube currents. The reconstructed images were postprocessed by volume rendering techniques (VRT) and multiplanar reconstruction (MPR). All of the suspected lesions were confirmed by surgery or follow-up studies. Twelve patients (total of 24 hands and feet, respectively) were found to be normal and the other eight patients (total of nine hands and feet, respectively) were found abnormal. Dual-energy techniques are very useful in visualizing tendons of the hands and feet, such as flexor pollicis longus tendon, flexor digitorum superficialis/profundus tendon, Achilles tendon, extensor hallucis longus tendon, and extensor digitorum longus tendon, etc. It can depict the whole shape of the tendons and their fixation points clearly. Peroneus longus tendon in the sole of the foot was not displayed very well. The distal ends of metacarpophalangeal joints with extensor digitoium tendon and extensor pollicis longus tendon were poorly shown. The lesions of tendons such as the circuitry, thickening, and adherence were also shown clearly. Dual-energy CT offers a new method to visualize tendons of the hand and foot. It could clearly display both anatomical structures and pathologic changes of hand and foot tendons.

A 16-channel receive, forced current excitation dual-transmit coil for breast imaging at 7T.

Directory of Open Access Journals (Sweden)

Samantha By

Full Text Available To enable high spatial and temporal breast imaging resolution via combined use of high field MRI, array coils, and forced current excitation (FCE multi channel transmit.A unilateral 16-channel receive array insert was designed for use in a transmit volume coil optimized for quadrature operation with dual-transmit RF shimming at 7 T. Signal-to-noise ratio (SNR maps, g-factor maps, and high spatial and temporal resolution in vivo images were acquired to demonstrate the utility of the coil architecture.The dual-transmit FCE coil provided homogeneous excitation and the array provided an increase in average SNR of 3.3 times (max 10.8, min 1.5 compared to the volume coil in transmit/receive mode. High resolution accelerated in vivo breast imaging demonstrated the ability to achieve isotropic spatial resolution of 0.5 mm within clinically relevant 90 s scan times, as well as the ability to perform 1.0 mm isotropic resolution imaging, 7 s per dynamics, with the use of bidirectional SENSE acceleration of up to R = 9.The FCE design of the transmit coil easily accommodates the addition of a sixteen channel array coil. The improved spatial and temporal resolution provided by the high-field array coil with FCE dual-channel transmit will ultimately be beneficial in lesion detection and characterization.

Dual-energy compared to single-energy CT in pediatric imaging: a phantom study for DECT clinical guidance

Energy Technology Data Exchange (ETDEWEB)

Zhu, Xiaowei; Servaes, Sabah; Darge, Kassa [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); University of Pennsylvania, The Perelman School of Medicine, Philadelphia, PA (United States); McCullough, William P. [University of Virginia Health System, Department of Radiology and Medical Imaging, Charlottesville, VA (United States); Mecca, Patricia [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States)

2016-11-15

Dual-energy CT technology is available on scanners from several vendors and offers significant advantages over classic single-energy CT technology in multiple clinical applications. Many studies have detailed dual-energy CT applications in adults and several have evaluated the relative radiation dose performance of dual-energy CT in adult imaging. However, little has been published on dual-energy CT imaging in the pediatric population, and the relative dose performance of dual-energy CT imaging in the pediatric population is not well described. When evaluating dual-energy CT technology for implementation into a routine clinical pediatric imaging practice, the radiation dose implications must be considered, and when comparing relative CT dose performance, image quality must also be evaluated. Therefore the purpose of this study is to develop dual-energy CT scan protocols based on our optimized single-energy scan protocols and compare the dose. We scanned the head, chest and abdomen regions of pediatric-size anthropomorphic phantoms with contrast inserts, using our optimized single-energy clinical imaging protocols on a Siemens Flash {sup registered} CT scanner. We then scanned the phantoms in dual-energy mode using matching image-quality reference settings. The effective CT dose index volume (CTDI{sub vol}) of the scans was used as a surrogate for relative dose in comparing the single- and dual-energy scans. Additionally, we evaluated image quality using visual assessment and contrast-to-noise ratio. Dual-energy CT scans of the head and abdomen were dose-neutral for all three phantoms. Dual-energy CT scans of the chest showed a relative dose increase over the single-energy scan for 1- and 5-year-old child-based age-equivalent phantoms, ranging 11-20%. Quantitative analysis of image quality showed no statistically significant difference in image quality between the single-energy and dual-energy scans. There was no clinically significant difference in image quality by

Lp-dual affine surface area

Science.gov (United States)

Wei, Wang; Binwu, He

2008-12-01

According to the notion of Lp-affine surface area by Lutwak, in this paper, we introduce the concept of Lp-dual affine surface area. Further, we establish the affine isoperimetric inequality and the Blaschke-Santaló inequality for Lp-dual affine surface area. Besides, the dual Brunn-Minkowski inequality for Lp-dual affine surface area is presented.

Dual symmetry in gauge theories

International Nuclear Information System (INIS)

Koshkarov, A.L.

1997-01-01

Continuous dual symmetry in electrodynamics, Yang-Mills theory and gravitation is investigated. Dual invariant which leads to badly nonlinear motion equations is chosen as a Lagrangian of the pure classical dual nonlinear electrodynamics. In a natural manner some dual angle which is determined by the electromagnetic strengths at the point of the time-space appears in the model. Motion equations may well be interpreted as the equations of the standard Maxwell theory with source. Alternative interpretation is the quasi-Maxwell linear theory with magnetic charge. Analogous approach is possible in the Yang-Mills theory. In this case the dual-invariant non-Abelian theory motion equations possess the same instanton solutions as the conventional Yang-Mills equations have. An Abelian two-parameter dual group is found to exist in gravitation. Irreducible representations have been obtained: the curvature tensor was expanded into the sum of twice anti-self-dual and self-dual parts. Gravitational instantons are defined as (real )solutions to the usual duality equations. Central symmetry solutions to these equations are obtained. The twice anti-self-dual part of the curvature tensor may be used for introduction of new gravitational equations generalizing Einstein''s equations. However, the theory obtained reduces to the conformal-flat Nordstroem theory

Quantitative prediction of respiratory tidal volume based on the external torso volume change: a potential volumetric surrogate

International Nuclear Information System (INIS)

Li Guang; Arora, Naveen C; Xie Huchen; Ning, Holly; Citrin, Deborah; Kaushal, Aradhana; Zach, Leor; Camphausen, Kevin; Miller, Robert W; Lu Wei; Low, Daniel

2009-01-01

An external respiratory surrogate that not only highly correlates with but also quantitatively predicts internal tidal volume should be useful in guiding four-dimensional computed tomography (4DCT), as well as 4D radiation therapy (4DRT). A volumetric surrogate should have advantages over external fiducial point(s) for monitoring respiration-induced motion of the torso, which deforms in synchronization with a patient-specific breathing pattern. This study establishes a linear relationship between the external torso volume change (TVC) and lung air volume change (AVC) by validating a proposed volume conservation hypothesis (TVC = AVC) throughout the respiratory cycle using 4DCT and spirometry. Fourteen patients' torso 4DCT images and corresponding spirometric tidal volumes were acquired to examine this hypothesis. The 4DCT images were acquired using dual surrogates in cine mode and amplitude-based binning in 12 respiratory stages, minimizing residual motion artifacts. Torso and lung volumes were calculated using threshold-based segmentation algorithms and volume changes were calculated relative to the full-exhalation stage. The TVC and AVC, as functions of respiratory stages, were compared, showing a high correlation (r = 0.992 ± 0.005, p 2 = 0.980) without phase shift. The AVC was also compared to the spirometric tidal volumes, showing a similar linearity (slope = 1.030 ± 0.092, R 2 = 0.947). In contrast, the thoracic and abdominal heights measured from 4DCT showed relatively low correlation (0.28 ± 0.44 and 0.82 ± 0.30, respectively) and location-dependent phase shifts. This novel approach establishes the foundation for developing an external volumetric respiratory surrogate.

Comparative magnetic studies of (Sm, Nd) trichloroacetates and their heteronuclear CuLn2(CCl3COO)8.6H2O systems: structure and spectroscopy of a new type of Eu trichloroacetate

International Nuclear Information System (INIS)

Wojciechowski, W.; Legendziewicz, J.; Puchalska, M.; Ciunik, Z.

2004-01-01

Two series of compounds: heteronuclear CuLn 2 (CCl 3 COO) 8 .6H 2 O (Ln = Nd and Sm) and their simple analogues Ln(CCl 3 COO) 3 .2H 2 O (Ln = Eu, Nd, Sm) were synthesized. New Eu(III) trichloroacetate; Eu(CCl 3 COO) 3 .3H 2 O.CH 3 OH was obtained, its molecular structure was determined by X-ray diffraction and compared with the data of respective systems reported earlier. Magnetization was measured and the susceptibility was derived in the limit of low field. Magnetic susceptibilities were calculated and discussed for series of homo- and hetero-nuclear chloroacetates.Untypical hysteresis was found (two loops) in samarium trichloroacetate. This phenomenon is most probably the effect of flops of spins in magnetic fields of 30,000Oe and very weak (if any) interaction intermediated by weak hydrogen bonding between the chains. A similar magnetic behavior was observed in neodymium carboxylate where the magnetic ordering was observed as a result of Nd-Nd interaction at low temperature (1.6K). For this system, the magnetic moment depends on magnitude of the magnetic field and ferromagnetic ordering appears at low temperatures. The strongest interactions of coupled ions and antiferromagnetic ordering with T N =6.5K were found in CuSm 2 (CCl 3 COO) 8 .6H 2 O single crystals.Heisenberg model was applied in the calculations for three interacting ions located linearly. The following relation was derived: χ M =Ng 2 μ β 2 kT(12)+(12)exp(J 2 /kT)+5exp(J 2 /kT)-exp(1,5J 1 /kT)2+2exp(J 2 /kT)+4exp(J 2 /kT)-exp(1,5J 1 /kT) and applied in calculations of the exchange integrals. Mechanism of the exchange interaction was discussed on the basis of the obtained results.

Dual energy CT

DEFF Research Database (Denmark)

Al-Najami, Issam; Drue, Henrik Christian; Steele, Robert

2017-01-01

and inaccurate with existing methods. Dual Energy Computed Tomography (DECT) enables qualitative tissue differentiation by simultaneous scanning with different levels of energy. We aimed to assess the feasibility of DECT in quantifying tumor response to neoadjuvant therapy in loco-advanced rectal cancer. METHODS...... to determine the average quantitative parameters; effective-Z, water- and iodine-concentration, Dual Energy Index (DEI), and Dual Energy Ratio (DER). These parameters were compared to the regression in the resection specimen as measured by the pathologist. RESULTS: Changes in the quantitative parameters...

Dual-beam, second-derivative tunable diode-laser infrared spectroscopy applied to trace-gas measurement

International Nuclear Information System (INIS)

Tallant, D.R.; Jungst, R.G.

1981-04-01

A dual beam diode laser spectrometer has been constructed using off-axis reflective optics. The spectrometer can be amplitude modulated for direct absorption measurements or frequency modulated to obtain derivative spectra. The spectrometer has high throughput, is easy to operate and align, provides good dual beam compensation, and has no evidence of the interference effects that have been observed in diode laser spectrometers using refractive optics. Unpurged, using second derivative techniques, the instrument has measured 108 parts-per-million CO (10 cm absorption cell, atmospheric pressure-broadened) with good signal/noise. With the replacement of marginal instrumental components, the signal/noise should be substantially increased. This instrument was developed to monitor the evolution of decomposition gases in sealed containers of small volume at atmospheric pressure

Dual Smarandache Curves and Smarandache Ruled Surfaces

OpenAIRE

Tanju KAHRAMAN; Mehmet ÖNDER; H. Hüseyin UGURLU

2013-01-01

In this paper, by considering dual geodesic trihedron (dual Darboux frame) we define dual Smarandache curves lying fully on dual unit sphere S^2 and corresponding to ruled surfaces. We obtain the relationships between the elements of curvature of dual spherical curve (ruled surface) x(s) and its dual Smarandache curve (Smarandache ruled surface) x1(s) and we give an example for dual Smarandache curves of a dual spherical curve.

Detection of pulmonary fat embolism with dual-energy CT: an experimental study in rabbits

Energy Technology Data Exchange (ETDEWEB)

Tang, Chun Xiang; Zhou, Chang Sheng; Zhao, Yan E.; Han, Zong Hong; Qi, Li; Zhang, Long Jiang; Lu, Guang Ming [Medical School of Nanjing University, Department of Medical Imaging, Jinling Hospital, Nanjing, Jiangsu (China); Schoepf, U.J. [Medical School of Nanjing University, Department of Medical Imaging, Jinling Hospital, Nanjing, Jiangsu (China); Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Mangold, Stefanie; Ball, B.D. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States)

2017-04-15

To evaluate the use of dual-energy CT imaging of the lung perfused blood volume (PBV) for the detection of pulmonary fat embolism (PFE). Dual-energy CT was performed in 24 rabbits before and 1 hour, 1 day, 4 days and 7 days after artificial induction of PFE via the right ear vein. CT pulmonary angiography (CTPA) and lung PBV images were evaluated by two radiologists, who recorded the presence, number, and location of PFE on a per-lobe basis. Sensitivity, specificity, and accuracy of CTPA and lung PBV for detecting PFE were calculated using histopathological evaluation as the reference standard. A total of 144 lung lobes in 24 rabbits were evaluated and 70 fat emboli were detected on histopathological analysis. The overall sensitivity, specificity and accuracy were 25.4 %, 98.6 %, and 62.5 % for CTPA, and 82.6 %, 76.0 %, and 79.2 % for lung PBV. Higher sensitivity (p < 0.001) and accuracy (p < 0.01), but lower specificity (p < 0.001), were found for lung PBV compared with CTPA. Dual-energy CT can detect PFE earlier than CTPA (all p < 0.01). Dual-energy CT provided higher sensitivity and accuracy in the detection of PFE as well as earlier detection compared with conventional CTPA in this animal model study. (orig.)

Demonstration and evaluation of dual-fuel technology; Demonstration och utvaerdering av dual-fuel-tekniken

Energy Technology Data Exchange (ETDEWEB)

Staalhammar, Per; Erlandsson, Lennart; Willner, Kristina (AVL MTC Motortestcenter AB (Sweden)); Johannesson, Staffan (Ecoplan AB (Sweden))

2011-06-15

There is an increased interest for Dual Fuel (methane-Diesel) applications in Sweden since this technology is seen as one of the more interesting options for a fast and cost effective introduction of biomethane as fuel for HD engines. The Dual Fuel technology has been used for many years, mainly for stationary purpose (generators, pumps and ships) while the Spark Ignited (SI) 'Otto' technology has been used for trucks and busses. One obstacle for introducing Dual Fuel technology for busses and trucks is the EU legislation that don't allow for HD on road certification of Dual Fuel applications. Challenges with the Dual Fuel technology is to develop cost effective applications that is capable of reaching low emissions (especially CH{sub 4} and NO{sub x}) in combination with high Diesel replacement in the test cycles used for on road applications. AVL MTC Motortestcenter AB (hereinafter called AVL) has on commission by SGC (Swedish Gas technical Centre) carried out this project with the objectives to analyze the Dual Fuel (Diesel-methane) technology with focus on emissions, fuel consumption and technical challenges. One important part of this project was to carry out emission tests on selected Dual Fuel applications in Sweden and to compile experiences from existing Dual Fuel technology. This report also summarizes other commonly used technologies for methane engines and compares the Dual Fuel with conventional Diesel and Otto technologies. The major challenges with Dual Fuel applications for on road vehicles will be to develop robust and cost effective solutions that meet the emission legislations (with aged catalysts) and to increase the Diesel replacement to achieve reasonable reduction of green house gases (GHG). This is especially important when biomethane is available as fuel but not Bio-Diesel. It will probably be possible to reach EURO V emission limits with advanced Dual Fuel systems but none of the tested systems reached EURO V emission levels

Dual Regression

OpenAIRE

Spady, Richard; Stouli, Sami

2012-01-01

We propose dual regression as an alternative to the quantile regression process for the global estimation of conditional distribution functions under minimal assumptions. Dual regression provides all the interpretational power of the quantile regression process while avoiding the need for repairing the intersecting conditional quantile surfaces that quantile regression often produces in practice. Our approach introduces a mathematical programming characterization of conditional distribution f...

Development of a dual-sinker densimeter for high-accuracy fluid P-V-T measurements

International Nuclear Information System (INIS)

McLinden, M.O.; Frederick, N.V.

1993-01-01

A dual-sinker densimeter to very accurately measure the pressure-volume-temperature (P-V-T) properties of fluids over a temperature range of 80 K to 520 K and at pressures up to 35 MPa is in the final stages of development at NIST. The density of a fluid is determined by measuring the difference in the buoyancy forces experienced by two sinkers of identical mass, surface area, and surface material, but very different volumes. The buoyancy forces on the sinkers are transmitted to a semi-microbalance by means of a magnetic suspension coupling. This paper reviews the principle of the measurement and describes the overall design of the system

Optimization experiment of gas oil direct injection valve for CNG dual fuel diesel engine

Energy Technology Data Exchange (ETDEWEB)

Kim, B.Y. [Chonnam National University Graduate School, Jeonju (Korea); Park, C. K. [Chonnam National University, Jeonju (Korea)

1999-04-01

In this study, we studied for a conversion from diesel engine to natural gas dual fuel engine. For this experimental, we tested about the injection quantity characteristics of pilot valve with the plunger diameter at the retraction volume and investigated to the engine performance and exhaust emissions with the nozzle hole number and injection nozzle diameter. As a result, when the plunger diameter is 7.5 mm at the retraction volume, 25 mm{sup 3}/st, the injection quantity characteristics develop. Also, when a nozzle type is 4*{phi} 0.24, total hydrocarbon(THC) emission reduce at low equivalence ratio. (author). 5 refs., 10 figs., 2 tabs.

Decision on risk-averse dual-channel supply chain under demand disruption

Science.gov (United States)

Yan, Bo; Jin, Zijie; Liu, Yanping; Yang, Jianbo

2018-02-01

We studied dual-channel supply chains using centralized and decentralized decision-making models. We also conducted a comparative analysis of the decisions before and after demand disruption. The study shows that the amount of change in decision-making is a linear function of the amount of demand disruption, and it is independent of the risk-averse coefficient. The optimal sales volume decision of the disturbing supply chain is related to market share and demand disruption in the decentralized decision-making model. The optimal decision is only influenced by demand disruption in the centralized decision-making model. The stability of the sales volume of the two models is related to market share and demand disruption. The optimal system production of the two models shows robustness, but their stable internals are different.

Clinical evaluation of dual-energy bone removal in CT angiography of the head and neck: comparison with conventional bone-subtraction CT angiography

International Nuclear Information System (INIS)

Deng, K.; Liu, C.; Ma, R.; Sun, C.; Wang, X.-M.; Ma, Z.-T.; Sun, X.-L.

2009-01-01

Aim: To evaluate the bone-subtraction effect of dual-energy bone removal in computed tomography angiography (CTA) of the head and neck in comparison with conventional bone-subtraction CTA. Material and Methods: The study comprised 52 patients who were divided into two groups at random, and examined using dual-source CT for head and neck CTA. Dual-energy bone removal CTA and conventional bone-subtraction CTA were applied to each of the two groups, respectively. The bone subtraction was performed automatically in both methods. Vascular structures, as well as brain tissue remained visible. The subtracted images were further processed with maximum intensity projection (MIP) and volume-rendering technique (VRT) for image evaluation. Two experienced radiologists reviewed the resulting subtracted and non-subtracted volume data with respect to the delineation and detection of image quality and vascular pathology. Results: The means of the weighted CT dose index (CTDIvol) for bone-removal dual-energy CTA and conventional bone-subtraction CTA were 20.56 ± 0.01 mGy and 25.57 ± 0.56 mGy, respectively. There was a significant difference between them. The percentage of carotid and vertebral arteries and all other vessels that could be successfully assessed with these two methods were 87.8, 68, and 83%, and 93.5, 91.8, and 92.6%, respectively. There were no significant differences in the visualization of the carotid arteries; however, there were significant differences in the visualization of the vertebral arteries. Conclusion: Compared with conventional bone-subtraction CTA, dual-energy bone-removal CTA had a lower radiation dose. It eliminated most bones in the head and neck successfully; however, the bone subtraction effect around the vertebral artery was unsatisfactory. Dual-energy bone-removal CTA provides a new method for detecting vascular diseases in routine clinical work.

Dual energy x-ray microtomography for development and inspection of advanced aerospace materials

International Nuclear Information System (INIS)

Alvarez, R.E.; Cao, Q.

1990-01-01

A key step in development of advanced composite materials is to characterize their internal structure and composition in a quantitative manner. In this paper, the authors describe a technique and an instrument that allows the measurements of the interior volume of the material. It has several key advantages over conventional computed tomography. The technique quantitatively measures the mass density and effective atomic number throughout the volume. Further, these measurements are made with microscopic (20 micrometer or better) spatial resolution. The technique is based on ARACOR's Tomoscope computed tomography instrument and on dual energy computed tomography. The authors describe the theory of the technique and show experimental measurements of metal matrix composite materials

Dual-band dual-polarized array for WLAN applications

CSIR Research Space (South Africa)

Steyn, JM

2009-01-01

Full Text Available dual-band dual-polarized (DBDP) antenna design for WLAN applications. The antenna is in the form of an array consisting of four double-dipole radiators. The basic radiating element consists of a rhombus shaped dipole above a planar ground plane... the ground planes and the respective feedlines. Substrate cuts and difierent heights for the horizontal feedlines were necessary to achieve the latter. The 2nd conflguration (for vertical polarization) has a slightly difierent feeding network layout...

Desempeño y emisiones de un motor de combustión interna con combustible dual Diesel – Gas natural ;Performance and emissions study of an internal combustion engine with dual fuel diesel - natural gas

Directory of Open Access Journals (Sweden)

Juan Miguel Mantilla González

2015-04-01

Full Text Available Muchos de los problemas reportados para los sistemas duales diesel- gas natural ocurren por mala dosificación del gas. Por esta razón se adaptó un sistema de alimentación dual con inyección electrónica de gas natural a un motor de combustión interna encendido por compresión. Se plantea un diseño experimental controlando el dosado de gas natural.Como resultado se obtiene un análisis comparativo entre los valoresde desempeño y emisiones desde la operación Diesel y Diesel-Gas natural. A partir de este análisis es posible observar que el desempeño del motor no se ve afectado por la operación del motor bajo el esquema Dual Diesel-GN, es decir que el motor funcionando bajo modo dual puede sostener las cargas solicitadas al motor. También se observa que la eficiencia volumétrica mejora bajo todas las condiciones de operación dual y las emisiones son mejores sólo cuando el motor trabaja a altas cargas. Many of the problems reported for dual diesel-natural gas systems occur due to poor gas dosage. For this reason a natural gas electronic injection feeding system was adapted to a compression ignitios internal combustion engine. An experimental design controlling the natural gas dosage is considered. As a result a comparative analysis between performance and emissions from the Diesel-and diesel-Natural Gas operation is obtained. From this analysis it is possible to see that engine performance is not affected by operation of the engine under the dual mode, i.e. the motor running under dual mode can support the loads applied to the engine. It is also observed that the volumetric efficiency improves under all conditions of operation and emissions from the dual mode of operation are better only when working at high engine loads.

Concurrent agreement between an anthropometric model to predict thigh volume and dual-energy X-Ray absorptiometry assessment in female volleyball players aged 14-18 years.

Science.gov (United States)

Tavares, Óscar M; Valente-Dos-Santos, João; Duarte, João P; Póvoas, Susana C; Gobbo, Luís A; Fernandes, Rômulo A; Marinho, Daniel A; Casanova, José M; Sherar, Lauren B; Courteix, Daniel; Coelho-E-Silva, Manuel J

2016-11-24

A variety of performance outputs are strongly determined by lower limbs volume and composition in children and adolescents. The current study aimed to examine the validity of thigh volume (TV) estimated by anthropometry in late adolescent female volleyball players. Dual-energy X-ray absorptiometry (DXA) measures were used as the reference method. Total and regional body composition was assessed with a Lunar DPX NT/Pro/MD+/Duo/Bravo scanner in a cross-sectional sample of 42 Portuguese female volleyball players aged 14-18 years (165.2 ± 0.9 cm; 61.1 ± 1.4 kg). TV was estimated with the reference method (TV-DXA) and with the anthropometric method (TV-ANTH). Agreement between procedures was assessed with Deming regression. The analysis also considered a calibration of the anthropometric approach. The equation that best predicted TV-DXA was: -0.899 + 0.876 × log 10 (body mass) + 0.113 × log 10 (TV-ANTH). This new model (NM) was validated using the predicted residual sum of squares (PRESS) method (R 2 PRESS  = 0.838). Correlation between the reference method and the NM was 0.934 (95%CI: 0.880-0.964, S y∙x  = 0.325 L). A new and accurate anthropometric method to estimate TV in adolescent female volleyball players was obtained from the equation of Jones and Pearson alongside with adjustments for body mass.

El anillo de los números duales

OpenAIRE

Jiménez, Haydee; Luque, Carlos Julio

2007-01-01

Se inicia con una presentación de la estructura de * - Álgebra de los números duales; se muestran diferentes representaciones que permiten la definición de potencias racionales de números duales, lo que exige una extensión de su estructura a un anillo de números duales con coeficientes complejos. Seguidamente se estudian la función exponencial dual y la función logaritmo dual que permiten la definición de potencias duales de un número dual; luego se estudian ecuaciones en los números duales h...

Nonword Reading: Comparing Dual-Route Cascaded and Connectionist Dual-Process Models with Human Data

Science.gov (United States)

Pritchard, Stephen C.; Coltheart, Max; Palethorpe, Sallyanne; Castles, Anne

2012-01-01

Two prominent dual-route computational models of reading aloud are the dual-route cascaded (DRC) model, and the connectionist dual-process plus (CDP+) model. While sharing similarly designed lexical routes, the two models differ greatly in their respective nonlexical route architecture, such that they often differ on nonword pronunciation. Neither…

Influence of fluoride on the bacterial composition of a dual-species biofilm composed of Streptococcus mutans and Streptococcus oralis.

Science.gov (United States)

Jung, Ji-Eun; Cai, Jian-Na; Cho, Sung-Dae; Song, Kwang-Yeob; Jeon, Jae-Gyu

2016-10-01

Despite the widespread use of fluoride for the prevention of dental caries, few studies have demonstrated the effects of fluoride on the bacterial composition of dental biofilms. This study investigated whether fluoride affects the proportion of Streptococcus mutans and S. oralis in mono- and dual-species biofilm models, via microbiological, biochemical, and confocal fluorescence microscope studies. Fluoride did not affect the bacterial count and bio-volume of S. mutans and S. oralis in mono-species biofilms, except for the 24-h-old S. mutans biofilms. However, fluoride reduced the proportion and bio-volume of S. mutans but did not decrease those of S. oralis during both S. oralis and S. mutans dual-species biofilm formation, which may be related to the decrease in extracellular polysaccharide formation by fluoride. These results suggest that fluoride may prevent the shift in the microbial proportion to cariogenic bacteria in dental biofilms, subsequently inhibiting the cariogenic bacteria dominant biofilm formation.

Quantitative prediction of respiratory tidal volume based on the external torso volume change: a potential volumetric surrogate

Energy Technology Data Exchange (ETDEWEB)

Li Guang; Arora, Naveen C; Xie Huchen; Ning, Holly; Citrin, Deborah; Kaushal, Aradhana; Zach, Leor; Camphausen, Kevin; Miller, Robert W [Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Lu Wei; Low, Daniel [Department of Radiation Oncology, Washington University School of Medicine, St Louis, MO 63110 (United States)], E-mail: ligeorge@mail.nih.gov

2009-04-07

An external respiratory surrogate that not only highly correlates with but also quantitatively predicts internal tidal volume should be useful in guiding four-dimensional computed tomography (4DCT), as well as 4D radiation therapy (4DRT). A volumetric surrogate should have advantages over external fiducial point(s) for monitoring respiration-induced motion of the torso, which deforms in synchronization with a patient-specific breathing pattern. This study establishes a linear relationship between the external torso volume change (TVC) and lung air volume change (AVC) by validating a proposed volume conservation hypothesis (TVC = AVC) throughout the respiratory cycle using 4DCT and spirometry. Fourteen patients' torso 4DCT images and corresponding spirometric tidal volumes were acquired to examine this hypothesis. The 4DCT images were acquired using dual surrogates in cine mode and amplitude-based binning in 12 respiratory stages, minimizing residual motion artifacts. Torso and lung volumes were calculated using threshold-based segmentation algorithms and volume changes were calculated relative to the full-exhalation stage. The TVC and AVC, as functions of respiratory stages, were compared, showing a high correlation (r = 0.992 {+-} 0.005, p < 0.0001) as well as a linear relationship (slope = 1.027 {+-} 0.061, R{sup 2} = 0.980) without phase shift. The AVC was also compared to the spirometric tidal volumes, showing a similar linearity (slope = 1.030 {+-} 0.092, R{sup 2} = 0.947). In contrast, the thoracic and abdominal heights measured from 4DCT showed relatively low correlation (0.28 {+-} 0.44 and 0.82 {+-} 0.30, respectively) and location-dependent phase shifts. This novel approach establishes the foundation for developing an external volumetric respiratory surrogate.

Can dual-energy CT replace perfusion CT for the functional evaluation of advanced hepatocellular carcinoma?

Science.gov (United States)

Mulé, Sébastien; Pigneur, Frédéric; Quelever, Ronan; Tenenhaus, Arthur; Baranes, Laurence; Richard, Philippe; Tacher, Vania; Herin, Edouard; Pasquier, Hugo; Ronot, Maxime; Rahmouni, Alain; Vilgrain, Valérie; Luciani, Alain

2018-05-01

To determine the degree of relationship between iodine concentrations derived from dual-energy CT (DECT) and perfusion CT parameters in patients with advanced HCC under treatment. In this single-centre IRB approved study, 16 patients with advanced HCC treated with sorafenib or radioembolization who underwent concurrent dynamic perfusion CT and multiphase DECT using a single source, fast kV switching DECT scanner were included. Written informed consent was obtained for all patients. HCC late-arterial and portal iodine concentrations, blood flow (BF)-related and blood volume (BV)-related perfusion parameters maps were calculated. Mixed-effects models of the relationship between iodine concentrations and perfusion parameters were computed. An adjusted p value (Bonferroni method) statistic (F)=28.52, padvanced HCC lesions, DECT-derived late-arterial iodine concentration is strongly related to both aBF and BV, while portal iodine concentration mainly reflects BV, offering DECT the ability to evaluate both morphological and perfusion changes. • Late-arterial iodine concentration is highly related to arterial BF and BV. • Portal iodine concentration mainly reflects tumour blood volume. • Dual-energy CT offers significantly decreased radiation dose compared with perfusion CT.

Spinning self-dual particles

International Nuclear Information System (INIS)

Gamboa, J.; Rivelles, V.O.

1989-02-01

We study spinning self-dual particles in two dimensions. They are obtained from the chiral bosonic particle through the square root technique. We show that the resulting field theory can be either fermionic or bosonic and that the associated self-dual field reveals its Lorentz tensor structure which remains hidden in the usual formulations. We also calculate the spinning self-dual particle propagators using the BFV formalism. (author) [pt

Dual-energy compared to single-energy CT in pediatric imaging: a phantom study for DECT clinical guidance

International Nuclear Information System (INIS)

Zhu, Xiaowei; Servaes, Sabah; Darge, Kassa; McCullough, William P.; Mecca, Patricia

2016-01-01

Dual-energy CT technology is available on scanners from several vendors and offers significant advantages over classic single-energy CT technology in multiple clinical applications. Many studies have detailed dual-energy CT applications in adults and several have evaluated the relative radiation dose performance of dual-energy CT in adult imaging. However, little has been published on dual-energy CT imaging in the pediatric population, and the relative dose performance of dual-energy CT imaging in the pediatric population is not well described. When evaluating dual-energy CT technology for implementation into a routine clinical pediatric imaging practice, the radiation dose implications must be considered, and when comparing relative CT dose performance, image quality must also be evaluated. Therefore the purpose of this study is to develop dual-energy CT scan protocols based on our optimized single-energy scan protocols and compare the dose. We scanned the head, chest and abdomen regions of pediatric-size anthropomorphic phantoms with contrast inserts, using our optimized single-energy clinical imaging protocols on a Siemens Flash "r"e"g"i"s"t"e"r"e"d CT scanner. We then scanned the phantoms in dual-energy mode using matching image-quality reference settings. The effective CT dose index volume (CTDI_v_o_l) of the scans was used as a surrogate for relative dose in comparing the single- and dual-energy scans. Additionally, we evaluated image quality using visual assessment and contrast-to-noise ratio. Dual-energy CT scans of the head and abdomen were dose-neutral for all three phantoms. Dual-energy CT scans of the chest showed a relative dose increase over the single-energy scan for 1- and 5-year-old child-based age-equivalent phantoms, ranging 11-20%. Quantitative analysis of image quality showed no statistically significant difference in image quality between the single-energy and dual-energy scans. There was no clinically significant difference in image quality

The use of dual material seals for packaging

International Nuclear Information System (INIS)

Temus, C.J.; Nichols, J.C.

2004-01-01

The use of dual material seals, metal and elastomeric for a transportation package, provides a viable option for packages requiring high temperature seal capability. Allowing the seal area to go to higher temperatures then allowed for all elastomeric seal reduce the necessity of providing thermal protection during a postulated accident condition fire. It also increases the options for impact limiting features that do not also mitigate the affects of accident thermal events. Typically, high temperature seals require the use of metal O-rings. Only one seal (typically identified as the containment seal) needs to survive the hypothetical accident conditions, including the high temperatures that may occur during the prescribed hypothetical thermal event. However, to expedite the assembly leakage rate testing of radioactive material packages, a dual O-ring seal arrangement is often used to allow creation of a relatively small volume test cavity between the seals. For any package that is being used on a frequent basis, the total cost of seals can be significantly reduced by using an elastomeric seal as the secondary seal. The elastomeric seal is not the containment boundary seal and does not need to survive the high temperature condition. To get the dual material O-ring seals to seat properly, a different approach has to be taken than with closure of a radioactive material package that does not use metallic O-ring(s). A metal O-ring requires an application of a seating force while the elastomeric package requires a certain percentage of deformation. This is further complicated when the seating force is developed using a multi-bolt closure. Because of the nature of multi-bolt closures, elastic interaction prevents the equal application of force. This paper develops the methods involved in properly closing and establishing containment when using dual material seals with a multi-bolt closure. These methods were demonstrated in two production casks requiring testing leak

Polymeric polyelectrolytes obtained from renewable sources for biodiesel wastewater treatment by dual-flocculation

Directory of Open Access Journals (Sweden)

E. A. M. Ribeiro

2017-06-01

Full Text Available Biodiesel wastewater generally contains high levels of oils, soaps and glycerol residues. This needs wastewater treatment. In this study, the biodiesel wastewater treatment was tested (industrial wastewater (EFID and laboratory wastewater (EFLB from biodiesel by performing flocculation and dual-flocculation with renewable polymers. Tannin and cationic hemicellulose (CH were used as cationic flocculant, and cellulose acetate sulfate (CAS was used as an anionic flocculant. Polyacrylamide (PAM was used as a reference anionic flocculant for result efficiencies analysis obtained with CAS (renewable source flocculant. The treatment efficacy in wastewater was evaluated by: turbidity removal, sludge volume formed, chemical oxygen demand (COD and total suspended solids (TSS. The obtained sludge was studied using thermogravimetric analysis (TG. The dual-flocculation application condition of the 25% proportion of tannin (T and 75% proportion of cationic hemicelluloses (i.e., T25/CH75 showed EFLB turbidity removal of 89.1% and 89.5% for CAS and PAM additions respectively, and for EFID of 67% and 41% for CAS and PAM additions respectively. The dual-flocculation performance suggested that the polyelectrolytes obtained from renewable sources can be used for treating biodiesel wastewater.

Left ventricular volume measurement in mice by conductance catheter: evaluation and optimization of calibration

DEFF Research Database (Denmark)

Nielsen, Jan Møller; Kristiansen, Steen B; Ringgaard, Steffen

2007-01-01

in mice (n = 52) with a Millar CC (SPR-839) and compared with MRI-derived volumes (V(MRI)). Significant correlations between V(CC) and V(MRI) [end-diastolic volume (EDV): R(2) = 0.85, P 2) = 0.88, P ... in the pulmonary artery was used to calibrate for parallel conductance and volume conversion was done by individual cylinder calibration. However, a significant underestimation was observed [EDV = -17.3 microl (-22.7 to -11.9 microl); ESV = -8.8 microl (-12.5 to -5.1 microl)]. Intravenous injection....... The dual-frequency method for estimation of parallel conductance failed to produce V(CC) that correlated with V(MRI). We conclude that selection of the calibration procedure for the CC has significant implications for the accuracy and precision of volume estimation and pressure-volume loop...

Dual thyroid ectopia

International Nuclear Information System (INIS)

Al-Akeely, Mohammed H.

2003-01-01

Ectopic thyroid gland is a rare embryological fault of thyroid development .Dual ectopic thyroid is more rare and only 8 cases have been reported in the literature. The author presents a case of dual ectopic thyroid in a 16 year old boy with an anterior red neck mass, which is gradually growing in size particularly in last 2 years. The initial diagnosis was thyroglossal duct cyst. Thyroid function test revealed elevated thyroid-stimulating hormone. Ultrasound of the neck did not show thyroid gland in its normal pre tracheal position. Thyroid scan (Technetium 99)revealed the diagnosis of dual thyroid ectopia(lingual and subhyoid). (author)

Global Model for Asymmetric, Diode-Type Dual Frequency Capacitive Discharge

Science.gov (United States)

Kim, Jisoo; Lieberman, M. A.; Lichtenberg, A. J.

2003-10-01

Dual frequency capacitive reactors can have desirable properties for dielectric etch: low cost, robust uniformity over large areas, and control of dissociation. In the ideal case, the high frequency power controls the plasma density (ion flux) and the low frequency voltage controls the ion bombarding energy. Typical operating conditions are: discharge radius 15-30 cm, length 1-3 cm, pressure 30-200 mTorr, high frequency 27.1-160 MHz, low frequency 2-13.6 MHz, and powers of 500-3000 W for both high and low frequencies. The decoupling of the high and low frequencies is an important feature of dual frequency capacitive discharges. In this work, we describe a global (volume-averaged) model having different top and bottom plate areas that incorporates particle balance, and ohmic and stochastic heating for high and low frequencies. The model is used to obtain the decoupling of high and low frequencies and to investigate limitations to ideal decoupling. Support provided by Lam Research, NSF Grant ECS-0139956, California industries, and UC-SMART Contract SM99-10051.

SU-F-T-660: Evaluating the Benefit of Using Dual-Function Fiducial Markers for In-Situ Delivery of Radiosenistizing Gold Nanoparticles During Image-Guided Radiotherapy

Energy Technology Data Exchange (ETDEWEB)

AlMansour, S; Chin, J; Sajo, E; Ngwa, W [University Massachusetts Lowell, Lowell, MA (United States)

2016-06-15

Purpose: Dual-function fiducials loaded with radiosensitizers, like gold nanoparticles (GNP), offer an innovative approach for ensuring geometric accuracy during image-guided radiotherapy (IGRT) and significantly increasing therapeutic efficacy due to controlled in-situ release of the radiosensitizers. This study retrospectively investigates the dosimetric benefit of using up to two such dual-function fiducial markers instead of traditional single function fiducials during IGRT. Methods: A computational code was developed to investigate the dosimetric benefit for 10 real patient tumor volumes of up to 6.5 cm diameter. The intra-tumoral space-time biodistribution of the GNP was modeled as in previous studies based on Fick’s second law. The corresponding dose-enhancement for each tumor voxel due to the GNP was also calculated for clinical 6MV beam configurations. Various loading concentrations (25–50 mg/g) were studied, as a function of GNP size, to determine potential for clinically significant dose enhancement. The time between initial implantation of dual-function fiducials to the beginning of radiotherapy was assumed to be 14 days as typical for many clinics. Results: A single dual-function fiducial could achieve at least a DEF of 1.2 for patients with tumors less than 1.4 cm diameter after 14 days. Replacing two single function fiducials with dual-function ones at the same locations achieved at least the required minimal DEF for tumors that are 2 cm diameter in 3 patients. The results also revealed dosimetrically better fiducial locations which could enable significant DEF when using one or two dual function fiducials. 2 nm sizes showed the most feasibility. Conclusion: The results highlight the potential of tumor sub-volume radiation boosting using GNP released from fiducials, and the ability to customize the DEF throughout the tumor by using two dual-function fiducials, varying the initial concentration and nanoparticle size. The results demonstrate

SU-F-T-660: Evaluating the Benefit of Using Dual-Function Fiducial Markers for In-Situ Delivery of Radiosenistizing Gold Nanoparticles During Image-Guided Radiotherapy

International Nuclear Information System (INIS)

AlMansour, S; Chin, J; Sajo, E; Ngwa, W

2016-01-01

Purpose: Dual-function fiducials loaded with radiosensitizers, like gold nanoparticles (GNP), offer an innovative approach for ensuring geometric accuracy during image-guided radiotherapy (IGRT) and significantly increasing therapeutic efficacy due to controlled in-situ release of the radiosensitizers. This study retrospectively investigates the dosimetric benefit of using up to two such dual-function fiducial markers instead of traditional single function fiducials during IGRT. Methods: A computational code was developed to investigate the dosimetric benefit for 10 real patient tumor volumes of up to 6.5 cm diameter. The intra-tumoral space-time biodistribution of the GNP was modeled as in previous studies based on Fick’s second law. The corresponding dose-enhancement for each tumor voxel due to the GNP was also calculated for clinical 6MV beam configurations. Various loading concentrations (25–50 mg/g) were studied, as a function of GNP size, to determine potential for clinically significant dose enhancement. The time between initial implantation of dual-function fiducials to the beginning of radiotherapy was assumed to be 14 days as typical for many clinics. Results: A single dual-function fiducial could achieve at least a DEF of 1.2 for patients with tumors less than 1.4 cm diameter after 14 days. Replacing two single function fiducials with dual-function ones at the same locations achieved at least the required minimal DEF for tumors that are 2 cm diameter in 3 patients. The results also revealed dosimetrically better fiducial locations which could enable significant DEF when using one or two dual function fiducials. 2 nm sizes showed the most feasibility. Conclusion: The results highlight the potential of tumor sub-volume radiation boosting using GNP released from fiducials, and the ability to customize the DEF throughout the tumor by using two dual-function fiducials, varying the initial concentration and nanoparticle size. The results demonstrate

Estimate of rain evaporation rates from dual-wavelength lidar measurements: comparison against a model analytical solution

Science.gov (United States)

Lolli, Simone; Di Girolamo, Paolo; Demoz, Belay; Li, Xiaowen; Welton, Ellsworth J.

2018-04-01

Rain evaporation significantly contributes to moisture and heat cloud budgets. In this paper, we illustrate an approach to estimate the median volume raindrop diameter and the rain evaporation rate profiles from dual-wavelength lidar measurements. These observational results are compared with those provided by a model analytical solution. We made use of measurements from the multi-wavelength Raman lidar BASIL.

Dual-mixed finite elements for the three-field Stokes model as a finite volume method on staggered grids

KAUST Repository

Kou, Jisheng; Sun, Shuyu

2017-01-01

In this paper, a new three-field weak formulation for Stokes problems is developed, and from this, a dual-mixed finite element method is proposed on a rectangular mesh. In the proposed mixed methods, the components of stress tensor are approximated

Mass thickness measurement of dual-sample by dual-energy X-rays

International Nuclear Information System (INIS)

Chen Mincong; Li Hongmei; Chen Ziyu; Shen Ji

2008-01-01

X-ray equivalent energy can be used to measure mass thicknesses of materials. Based on this, a method of mass thickness measurement of dual-sample was discussed. It was found that in the range of sample mass thickness under investigation, the equivalent mass attenuation coefficient of a component could be used to compute mass thicknesses of a dual-sample, with relative errors of less than 5%. Mass thickness measurement of a fish sample was performed, and the fish bone and flesh could be displayed separately and clearly by their own mass thicknesses. This indicates that the method is effective in mass thickness measurement of dual-sample of suitable thicknesses. (authors)

New Fukui, dual and hyper-dual kernels as bond reactivity descriptors.

Science.gov (United States)

Franco-Pérez, Marco; Polanco-Ramírez, Carlos-A; Ayers, Paul W; Gázquez, José L; Vela, Alberto

2017-06-21

We define three new linear response indices with promising applications for bond reactivity using the mathematical framework of τ-CRT (finite temperature chemical reactivity theory). The τ-Fukui kernel is defined as the ratio between the fluctuations of the average electron density at two different points in the space and the fluctuations in the average electron number and is designed to integrate to the finite-temperature definition of the electronic Fukui function. When this kernel is condensed, it can be interpreted as a site-reactivity descriptor of the boundary region between two atoms. The τ-dual kernel corresponds to the first order response of the Fukui kernel and is designed to integrate to the finite temperature definition of the dual descriptor; it indicates the ambiphilic reactivity of a specific bond and enriches the traditional dual descriptor by allowing one to distinguish between the electron-accepting and electron-donating processes. Finally, the τ-hyper dual kernel is defined as the second-order derivative of the Fukui kernel and is proposed as a measure of the strength of ambiphilic bonding interactions. Although these quantities have never been proposed, our results for the τ-Fukui kernel and for τ-dual kernel can be derived in zero-temperature formulation of the chemical reactivity theory with, among other things, the widely-used parabolic interpolation model.

Dual Credit Report

Science.gov (United States)

Light, Noreen

2016-01-01

In 2015, legislation to improve access to dual-credit programs and to reduce disparities in access and completion--particularly for low income and underrepresented students--was enacted. The new law focused on expanding access to College in the High School but acknowledged issues in other dual-credit programs and reinforced the notion that cost…

Vertebral bone mineral measurement using dual photon absorptiometry and computed tomography

International Nuclear Information System (INIS)

Eriksson, S.; Isberg, B.; Lindgren, U.; Huddinge Univ. Hospital

1988-01-01

The lumbar spine of 14 cadavers was studied both by 153 Gd dual photon absorptiometry (DPA) and quantitative computed tomography (QCT) at 96 and 125 kVp. The intact spine and the individual vertebrae were analyzed. After these measurements the ash content of the vertebral body, the posterior elements, and the transverse processes was determined. The fat content of the vertebral body as well as its volume was also measured. With DPA, the bone mineral content (BMC) determined in situ as well as on excised spine specimens correlated highly with the amount of total vertebral ash (r > 0.92, SEE 0.81, SEE 3 ). The so-called corpus density and central density determinations were less accurate. No difference in accuracy was found between measurements when using 3 mm and 4.5 mm step intervals. Variations in the distribution of mineral between the vertebral body and the posterior elements contribute to the error in predicting vertebral body mineral with DPA. QCT gave a smaller error when a cylindric portion of the vertebral body with a 20 diameter was measured compared with one with a 9 mm diameter, when the dual energy technique was used (p 3 ). Single energy QCT was insignificantly less accurate than dual energy QCT. Only small differences were found between vertebrae with high fat density of the vertebral body when single or dual QCT was used. QCT was more accurate than DPA in the prediction of the mineral density of individual vertebral bodies (p < 0.05) but no difference was found when the average values for the lumbar spine were calculated. (orig.)

Does SEGUE/SDSS indicate a dual galactic halo?

International Nuclear Information System (INIS)

Schönrich, Ralph; Asplund, Martin; Casagrande, Luca

2014-01-01

We re-examine recent claims of observational evidence for a dual Galactic halo in SEGUE/SDSS data, and trace them back to improper error treatment and neglect of selection effects. In particular, the detection of a vertical abundance gradient in the halo can be explained as a metallicity bias in distance. A similar bias and the impact of disk contamination affect the sample of blue horizontal branch stars. These examples highlight why non-volume complete samples require forward modeling from theoretical models or extensive bias-corrections. We also show how observational uncertainties produce the specific non-Gaussianity in the observed azimuthal velocity distribution of halo stars, which can be erroneously identified as two Gaussian components. A single kinematic component yields an excellent fit to the observed data, when we model the measurement process including distance uncertainties. Furthermore, we show that sample differences in proper motion space are the direct consequence of kinematic cuts and are enhanced when distance estimates are less accurate. Thus, their presence is neither proof of a separate population nor a measure of reliability for the applied distances. We conclude that currently there is no evidence from SEGUE/SDSS that would favor a dual Galactic halo over a single halo that is full of substructure.

spinning self-dual particles

International Nuclear Information System (INIS)

Gamboa, J.; Rivelles, V.O.

1989-01-01

Self-dual particles in two-dimensions are presented. They were obtained from chiral boson particle by square root technique. The propagator of spinning self-dual particle is calculated using the BFV formalism. (M.C.K.)

Method of phase-Doppler anemometry free from the measurement-volume effect.

Science.gov (United States)

Qiu, H; Hsu, C T

1999-05-01

A novel method is developed to improve the accuracy of particle sizing in laser phase-Doppler anemometry (PDA). In this method the vector sum of refractive and reflective rays is taken into consideration in describing a dual-mechanism-scattering model caused by a nonuniformly illuminated PDA measurement volume. The constraint of the single-mechanism-scattering model in the conventional PDA is removed. As a result the error caused by the measurement-volume effect, which consists of a Gaussian-beam defect and a slit effect, can be eliminated. This new method can be easily implemented with minimal modification of the conventional PDA system. The results of simulation based on the generalized Lorenz-Mie theory show that the new method can provide a PDA system free from the measurement-volume effect.

In vitro differentiation of renal stone composition using dual-source, dual-energy CT

International Nuclear Information System (INIS)

Zhou Changsheng; Zhang Longjiang; Xu Feng; Qi Li; Zhao Yan'e; Zheng Ling; Huang Wei; Liu Youhuang; Lu Guangming

2012-01-01

Objective: To evaluate the ability of dual-source. dual-energy CT in differentiating uric acid stones from non-uric acid stones with infrared spectroscopy as reference standard. Materials and Methods: Urinary calculus from 308 patients were scanned in first generation dual-source CT with dual-energy mode between July 2011 and June 2012. Renal Stone application was used to analyze their composition. The uric acid stones color were coded red and non-uric acid stones were blue. CT values were measured in 60 selective urinary calculus including 30 uric acid stones and 30 non-uric acid stones. The accuracy of dual energy CT to differentiate uric acid and no-uric acid stones was calculated. Results: Of 308 patients, 60 patients had uric acid stones and 248 non-uric acid stones. No difference was found for uric acid stone at 80 kV and 140 kV (375.8±69.2 HU vs. 374.1±69.4 HU; t=-0.217, P=0.830), while CT values of non-uric acid stones were higher at 80 kV than those at 140 kV (1455.1±312.4 HU vs. 1039.6±194.4 HU; t=-12.16. P<0.001). CT values of non-uric acid stones at 80 kV, 140 kV, and average weighted images (1455.1±312.4 HU, 1 039.6±194.4 HU, and 882.0±176.4 HU, respectively) were higher than those of uric acid stones (375.8±69.2 HU, 374.1±69.4 HU, and 366.3±80.1 HU, respectively; P<0.001). With infrared spectrum findings as reference standard, the accuracy of dual energy CT in differentiating uric acid stones from non-uric acid stones was 100%. Conclusions: Dual-source, dual-energy CT can accurately differentiate uric acid stones from non-uric acid stones, and plays an important role in treatment planning of renal stones. (authors)

Dual coil ignition system

Energy Technology Data Exchange (ETDEWEB)

Huberts, Garlan J.; Qu, Qiuping; Czekala, Michael Damian

2017-03-28

A dual coil ignition system is provided. The dual coil ignition system includes a first inductive ignition coil including a first primary winding and a first secondary winding, and a second inductive ignition coil including a second primary winding and a second secondary winding, the second secondary winding connected in series to the first secondary winding. The dual coil ignition system further includes a diode network including a first diode and a second diode connected between the first secondary winding and the second secondary winding.

Accurate measurement of heteronuclear dipolar couplings by phase-alternating R-symmetry (PARS) sequences in magic angle spinning NMR spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Hou, Guangjin, E-mail: hou@udel.edu, E-mail: tpolenov@udel.edu; Lu, Xingyu, E-mail: luxingyu@udel.edu, E-mail: lexvega@comcast.net; Vega, Alexander J., E-mail: luxingyu@udel.edu, E-mail: lexvega@comcast.net; Polenova, Tatyana, E-mail: hou@udel.edu, E-mail: tpolenov@udel.edu [Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA and Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave., Pittsburgh, Pennsylvania 15261 (United States)

2014-09-14

We report a Phase-Alternating R-Symmetry (PARS) dipolar recoupling scheme for accurate measurement of heteronuclear {sup 1}H-X (X = {sup 13}C, {sup 15}N, {sup 31}P, etc.) dipolar couplings in MAS NMR experiments. It is an improvement of conventional C- and R-symmetry type DIPSHIFT experiments where, in addition to the dipolar interaction, the {sup 1}H CSA interaction persists and thereby introduces considerable errors in the dipolar measurements. In PARS, phase-shifted RN symmetry pulse blocks applied on the {sup 1}H spins combined with π pulses applied on the X spins at the end of each RN block efficiently suppress the effect from {sup 1}H chemical shift anisotropy, while keeping the {sup 1}H-X dipolar couplings intact. Another advantage over conventional DIPSHIFT experiments, which require the signal to be detected in the form of a reduced-intensity Hahn echo, is that the series of π pulses refocuses the X chemical shift and avoids the necessity of echo formation. PARS permits determination of accurate dipolar couplings in a single experiment; it is suitable for a wide range of MAS conditions including both slow and fast MAS frequencies; and it assures dipolar truncation from the remote protons. The performance of PARS is tested on two model systems, [{sup 15}N]-N-acetyl-valine and [U-{sup 13}C,{sup 15}N]-N-formyl-Met-Leu-Phe tripeptide. The application of PARS for site-resolved measurement of accurate {sup 1}H-{sup 15}N dipolar couplings in the context of 3D experiments is presented on U-{sup 13}C,{sup 15}N-enriched dynein light chain protein LC8.

Comparison of the artifacts caused by metallic implants in breast MRI using dual-echo dixon versus conventional fat-suppression techniques.

Science.gov (United States)

Le, Yuan; Kipfer, Hal D; Majidi, Shadie S; Holz, Stephanie; Lin, Chen

2014-09-01

The purpose of this article is to evaluate and compare the artifacts caused by metal implants in breast MR images acquired with dual-echo Dixon and two conventional fat-suppression techniques. Two types of biopsy markers were embedded into a uniform fat-water emulsion. T1-weighted gradient-echo images were acquired on a clinical 3-T MRI scanner with three different fat-suppression techniques-conventional or quick fat saturation, spectrally selective adiabatic inversion recovery (SPAIR), and dual-echo Dixon-and the 3D volumes of artifacts were measured. Among the subjects of a clinical breast MRI study using the same scanner, five patients were found to have one or more metal implants. The artifacts in Dixon and SPAIR fat-suppressed images were evaluated by three radiologists, and the results were compared with those of the phantom study. In the phantom study, the artifacts appeared as interleaved bright and dark rings on SPAIR and quick-fat-saturation images, whereas they appeared as dark regions with a thin bright rim on Dixon images. The artifacts imaged with the Dixon technique had the smallest total volume. However, the reviewers found larger artifact diameters on patient images using the Dixon sequence because only the central region was recognized as an artifact on the SPAIR images. Metal implants introduce artifacts of different types and sizes, according to the different fat-suppression techniques used. The dual-echo Dixon technique produces a larger central void, allowing the implant to be easily identified, but presents a smaller overall artifact volume by obscuring less area in the image, according to a quantitative phantom study.

Brain activation during dual-task processing is associated with cardiorespiratory fitness and performance in older adults

Directory of Open Access Journals (Sweden)

Chelsea N Wong

2015-08-01

Full Text Available Higher cardiorespiratory fitness is associated with better cognitive performance and enhanced brain activation. Yet, the extent to which cardiorespiratory fitness-related brain activation is associated with better cognitive performance is not well understood. In this cross-sectional study, we examined whether the association between cardiorespiratory fitness and executive function was mediated by greater prefrontal cortex activation in healthy older adults. Brain activation was measured during dual-task performance with functional magnetic resonance imaging in a sample of 128 healthy older adults (59-80 years. Higher cardiorespiratory fitness was associated with greater activation during dual-task processing in several brain areas including the anterior cingulate and supplementary motor cortex (ACC/SMA, thalamus and basal ganglia, right motor/somatosensory cortex and middle frontal gyrus, and left somatosensory cortex, controlling for age, sex, education, and gray matter volume. Of these regions, greater ACC/SMA activation mediated the association between cardiorespiratory fitness and dual-task performance. We provide novel evidence that cardiorespiratory fitness may support cognitive performance by facilitating brain activation in a core region critical for executive function.

Dynamic dual-tracer PET reconstruction.

Science.gov (United States)

Gao, Fei; Liu, Huafeng; Jian, Yiqiang; Shi, Pengcheng

2009-01-01

Although of important medical implications, simultaneous dual-tracer positron emission tomography reconstruction remains a challenging problem, primarily because the photon measurements from dual tracers are overlapped. In this paper, we propose a simultaneous dynamic dual-tracer reconstruction of tissue activity maps based on guidance from tracer kinetics. The dual-tracer reconstruction problem is formulated in a state-space representation, where parallel compartment models serve as continuous-time system equation describing the tracer kinetic processes of dual tracers, and the imaging data is expressed as discrete sampling of the system states in measurement equation. The image reconstruction problem has therefore become a state estimation problem in a continuous-discrete hybrid paradigm, and H infinity filtering is adopted as the estimation strategy. As H infinity filtering makes no assumptions on the system and measurement statistics, robust reconstruction results can be obtained for the dual-tracer PET imaging system where the statistical properties of measurement data and system uncertainty are not available a priori, even when there are disturbances in the kinetic parameters. Experimental results on digital phantoms, Monte Carlo simulations and physical phantoms have demonstrated the superior performance.

Dual leadership in a hospital practice

DEFF Research Database (Denmark)

Thude, Bettina Ravnborg; Thomsen, Svend Erik; Stenager, Egon

2017-01-01

, this study aims to analyse three different dual leadership pairs at a Danish hospital. Furthermore, this study develops a tool to characterize dual leadership teams from each other. Design/methodology/approach This is a qualitative study using semi-structured interviews. Six leaders were interviewed...... to clarify how dual leadership works in a hospital context. All interviews were transcribed and coded. During coding, focus was on the nine principles found in the literature and another principle was found by looking at the themes that were generic for all six interviews. Findings Results indicate......Purpose Despite the practice of dual leadership in many organizations, there is relatively little research on the topic. Dual leadership means two leaders share the leadership task and are held jointly accountable for the results of the unit. To better understand how dual leadership works...

Spray-Wall Impingement of Diesel-CNG Dual Fuel Jet using Schlieren Imaging Technique

Directory of Open Access Journals (Sweden)

Ismael Mhadi Abaker

2014-07-01

Full Text Available Natural gas is a low cost fuel with high availability in nature. However, it cannot be used by itself in conventional diesel engines due to its low flame speed and high ignition temperature. The addition of a secondary fuel to enhance the mixture formation and combustion process facilitate its wider use as an alternative fuel. An experimental study was performed to investigate the diesel-CNG dual fuel jet-wall impingement. A constant volume optical chamber was designed to facilitate maximum optical access for the study of the jet-wall impingement at different injection pressures, temperatures and injector-wall distances. The bottom plate of the test rig was made of aluminum (piston material and it was heated up to 500 K at ambient pressure. An injector driver was used to control the single-hole nozzle diesel injector combined with a natural gas injector. The injection timing of both injectors was synchronized with a camera trigger. The jet-wall impingement of diesel and diesel-CNG dual fuel jets was recorded with a high speed camera using Schlieren imaging technique and associated image processing software. The measurements of the jet radial penetration were higher in diesel-CNG dual fuel while the jet height travel along were higher in the case of diesel single fuel.

Comparison of Tomo-PIV Versus Dual Plane PIV on a Synthetic Jet Flow

Science.gov (United States)

Wernet, Mark P.

2017-01-01

Particle Imaging Velocimetry (PIV) is a planar velocity measurement technique that has found widespread use across a wide class of engineering disciplines. Tomographic PIV (tomoPIV) is an extension of the traditional PIV technique whereby the velocity across a volume of fluid is measured. TomoPIV provides additional fluid mechanical properties of the flow due to the adjacent planes of velocity information that are extracted. Dual Plane PIV is another approach for providing cross-plane flow field properties. Dual Plane PIV and tomoPIV provide all of the same flow properties, albeit through very different routes with significantly different levels of effort, hence a comparison of their application and performance would prove beneficial in a well-known, highly three dimensional flow field. A synthetic jet flow which has a wide range of flow field features including high velocity gradients and regions of high vorticity was used as a rigorous test bed to determine the capabilities limitations of the Dual Plane PIV and tomoPIV techniques. The results show that compressing 3D particle field information down to a limited number of views does not permit the accurate reconstruction of the flow field. The traditional thin sheet techniques are the best approach for accurate flow field measurements.

Cognitive and motor dual task gait training improve dual task gait performance after stroke - A randomized controlled pilot trial.

Science.gov (United States)

Liu, Yan-Ci; Yang, Yea-Ru; Tsai, Yun-An; Wang, Ray-Yau

2017-06-22

This study investigated effects of cognitive and motor dual task gait training on dual task gait performance in stroke. Participants (n = 28) were randomly assigned to cognitive dual task gait training (CDTT), motor dual task gait training (MDTT), or conventional physical therapy (CPT) group. Participants in CDTT or MDTT group practiced the cognitive or motor tasks respectively during walking. Participants in CPT group received strengthening, balance, and gait training. The intervention was 30 min/session, 3 sessions/week for 4 weeks. Three test conditions to evaluate the training effects were single walking, walking while performing cognitive task (serial subtraction), and walking while performing motor task (tray-carrying). Parameters included gait speed, dual task cost of gait speed (DTC-speed), cadence, stride time, and stride length. After CDTT, cognitive-motor dual task gait performance (stride length and DTC-speed) was improved (p = 0.021; p = 0.015). After MDTT, motor dual task gait performance (gait speed, stride length, and DTC-speed) was improved (p = 0.008; p = 0.008; p = 0.008 respectively). It seems that CDTT improved cognitive dual task gait performance and MDTT improved motor dual task gait performance although such improvements did not reach significant group difference. Therefore, different types of dual task gait training can be adopted to enhance different dual task gait performance in stroke.

Accuracy of iodine quantification using dual energy CT in latest generation dual source and dual layer CT.

Science.gov (United States)

Pelgrim, Gert Jan; van Hamersvelt, Robbert W; Willemink, Martin J; Schmidt, Bernhard T; Flohr, Thomas; Schilham, Arnold; Milles, Julien; Oudkerk, Matthijs; Leiner, Tim; Vliegenthart, Rozemarijn

2017-09-01

To determine the accuracy of iodine quantification with dual energy computed tomography (DECT) in two high-end CT systems with different spectral imaging techniques. Five tubes with different iodine concentrations (0, 5, 10, 15, 20 mg/ml) were analysed in an anthropomorphic thoracic phantom. Adding two phantom rings simulated increased patient size. For third-generation dual source CT (DSCT), tube voltage combinations of 150Sn and 70, 80, 90, 100 kVp were analysed. For dual layer CT (DLCT), 120 and 140 kVp were used. Scans were repeated three times. Median normalized values and interquartile ranges (IQRs) were calculated for all kVp settings and phantom sizes. Correlation between measured and known iodine concentrations was excellent for both systems (R = 0.999-1.000, p < 0.0001). For DSCT, median measurement errors ranged from -0.5% (IQR -2.0, 2.0%) at 150Sn/70 kVp and -2.3% (IQR -4.0, -0.1%) at 150Sn/80 kVp to -4.0% (IQR -6.0, -2.8%) at 150Sn/90 kVp. For DLCT, median measurement errors ranged from -3.3% (IQR -4.9, -1.5%) at 140 kVp to -4.6% (IQR -6.0, -3.6%) at 120 kVp. Larger phantom sizes increased variability of iodine measurements (p < 0.05). Iodine concentration can be accurately quantified with state-of-the-art DECT systems from two vendors. The lowest absolute errors were found for DSCT using the 150Sn/70 kVp or 150Sn/80 kVp combinations, which was slightly more accurate than 140 kVp in DLCT. • High-end CT scanners allow accurate iodine quantification using different DECT techniques. • Lowest measurement error was found in scans with largest photon energy separation. • Dual-source CT quantified iodine slightly more accurately than dual layer CT.

Dual of QCD with One Adjoint Fermion

DEFF Research Database (Denmark)

Mojaza, Matin; Nardecchia, Marco; Pica, Claudio

2011-01-01

We construct the magnetic dual of QCD with one adjoint Weyl fermion. The dual is a consistent solution of the 't Hooft anomaly matching conditions, allows for flavor decoupling and remarkably constitutes the first nonsupersymmetric dual valid for any number of colors. The dual allows to bound...

Technical Note: Insertion of digital lesions in the projection domain for dual-source, dual-energy CT.

Science.gov (United States)

Ferrero, Andrea; Chen, Baiyu; Li, Zhoubo; Yu, Lifeng; McCollough, Cynthia

2017-05-01

To compare algorithms performing material decomposition and classification in dual-energy CT, it is desirable to know the ground truth of the lesion to be analyzed in real patient data. In this work, we developed and validated a framework to insert digital lesions of arbitrary chemical composition into patient projection data acquired on a dual-source, dual-energy CT system. A model that takes into account beam-hardening effects was developed to predict the CT number of objects with known chemical composition. The model utilizes information about the x-ray energy spectra, the patient/phantom attenuation, and the x-ray detector energy response. The beam-hardening model was validated on samples of iodine (I) and calcium (Ca) for a second-generation dual-source, dual-energy CT scanner for all tube potentials available and a wide range of patient sizes. The seven most prevalent mineral components of renal stones were modeled and digital stones were created with CT numbers computed for each patient/phantom size and x-ray energy spectra using the developed beam-hardening model. Each digital stone was inserted in the dual-energy projection data of a water phantom scanned on a dual-source scanner and reconstructed with the routine algorithms in use in our practice. The geometry of the forward projection for dual-energy data was validated by comparing CT number accuracy and high-contrast resolution of simulated dual-energy CT data of the ACR phantom with experimentally acquired data. The beam-hardening model and forward projection method accurately predicted the CT number of I and Ca over a wide range of tube potentials and phantom sizes. The images reconstructed after the insertion of digital kidney stones were consistent with the images reconstructed from the scanner, and the CT number ratios for different kidney stone types were consistent with data in the literature. A sample application of the proposed tool was also demonstrated. A framework was developed and validated

Computer code and users' guide for the preliminary analysis of dual-mode space nuclear fission solid core power and propulsion systems, NUROC3A. AMS report No. 1239b

Energy Technology Data Exchange (ETDEWEB)

Nichols, R.A.; Smith, W.W.

1976-06-30

The three-volume report describes a dual-mode nuclear space power and propulsion system concept that employs an advanced solid-core nuclear fission reactor coupled via heat pipes to one of several electric power conversion systems. The second volume describes the computer code and users' guide for the preliminary analysis of the system.

Association between increased epicardial adipose tissue volume and coronary plaque composition

OpenAIRE

Yamashita, Kennosuke; Yamamoto, Myong Hwa; Ebara, Seitarou; Okabe, Toshitaka; Saito, Shigeo; Hoshimoto, Koichi; Yakushiji, Tadayuki; Isomura, Naoei; Araki, Hiroshi; Obara, Chiaki; Ochiai, Masahiko

2013-01-01

To assess the relationship between epicardial adipose tissue volume (EATV) and plaque vulnerability in significant coronary stenosis using a 40-MHz intravascular ultrasound (IVUS) imaging system (iMap-IVUS), we analyzed 130 consecutive patients with coronary stenosis who underwent dual-source computed tomography (CT) and cardiac catheterization. Culprit lesions were imaged by iMap-IVUS before stenting. The iMAP-IVUS system classified coronary plaque components as fibrous, lipid, necrotic, or ...

Dual antiretroviral therapy for HIV infection.

Science.gov (United States)

Soriano, Vicente; Fernandez-Montero, Jose Vicente; Benitez-Gutierrez, Laura; Mendoza, Carmen de; Arias, Ana; Barreiro, Pablo; Peña, José M; Labarga, Pablo

2017-08-01

For two decades, triple combinations of antiretrovirals have been the standard treatment for HIV infection. The challenges of such lifelong therapy include long-term side effects, high costs and reduced drug adherence. The recent advent of more potent and safer antiretrovirals has renewed the interest for simpler HIV regimens. Areas covered: We discuss the pros and cons of dual antiretroviral therapies in both drug-naïve and in treatment-experienced patients with viral suppression (switch strategy). Expert opinion: Some dual antiretroviral regimens are safe and efficacious, particularly as maintenance therapy. At this time, combinations of dolutegravir plus rilpivirine represent the best dual regimen. Longer follow-up and larger study populations are needed before supporting dolutegravir plus lamivudine. In contrast, dual therapy based on maraviroc is less effective. Although dual regimens with boosted protease inhibitors plus either lamivudine or raltegravir may be effective, they are penalized by metabolic side effects and risk for drug interactions. The newest dual regimens could save money, reduce toxicity and spare drug options for the future. For the first time in HIV therapeutics, less can be more. Dual therapy switching has set up a new paradigm in HIV treatment that uses induction-maintenance.

Dual Enrollment Academy Programs

Science.gov (United States)

Gonzalez, Nicolas; Chavez, Guadalupe

2009-01-01

Dual Enrollment Engineering (DEEA) and Medical Science (DEMSA) Academies are two-year dual enrollment programs for high school students. Students explore engineering and medical careers through college coursework. Students prepare for higher education in engineering and medical fields while completing associate degrees in biology or engineering…

A Dual Egalitarian Solution

NARCIS (Netherlands)

Klijn, F.; Slikker, M.; Tijs, S.H.

2000-01-01

In this note we introduce an egalitarian solution, called the dual egalitarian solution, that is the natural counterpart of the egalitarian solution of Dutta and Ray (1989).We prove, among others, that for a convex game the egalitarian solution coincides with the dual egalitarian solution for its

Dual QCD: A review

International Nuclear Information System (INIS)

Baker, M.; Ball, J.S.; Zachariasen, F.

1991-01-01

We review the attempts to use dual (electric) vector potentials rather than the standard magnetic vector potentials to describe QCD, particularly in the infrared regime. The use of dual potentials is motivated by the fact that in classical electrodynamics, in a medium with a dielectric constant vanishing at small momenta (as is believed to be the case in QCD), electric potentials provide a far more convenient language than do magnetic potentials. To begin with, we outline attempts to construct the QCD Lagrangian in terms of dual potentials and describe the various possibilities, their shortcomings and advantages, which so far exist. We then proceed to use the most attractive (albeit consistent as a field theory only at the tree level) of these Lagrangians in a number of applications. We show that it describes a non-Abelian dual superconductor (so that it automatically confines color), derive the static quark-antiquark potential, and various temperature dependent effects, such as deconfinement and chiral symmetry breaking. (orig.)

A fast dual wavelength laser beam fluid-less optical CT scanner for radiotherapy 3D gel dosimetry II: dosimetric performance

Science.gov (United States)

Ramm, Daniel

2018-02-01

New clinical radiotherapy dosimetry systems need comprehensive demonstration of measurement quality. Practicality and reliability are other important aspects for clinical dosimeters. In this work the performance of an optical CT scanner for true 3D dosimetry is assessed using a radiochromic gel dosimeter. The fluid-less scanner utilised dual lasers to avoid the necessity for pre-irradiation scans and give greater robustness of image quality, enhancing practicality. Calibration methods using both cuvettes and reconstructed volumes were developed. Dosimetric accuracy was similar for dual and single wavelength measurements, except that cuvette calibration reliability was reduced for dual wavelength without pre-irradiation scanning. Detailed performance parameters were specified for the dosimetry system indicating the suitability for clinical use. The most significant limitations of the system were due to the gel dosimeter rather than the optical CT scanner. Quality assurance guidelines were developed to maintain dosimetry system performance in routine use.

Dual Carbon-Confined SnO2 Hollow Nanospheres Enabling High Performance for the Reversible Storage of Alkali Metal Ions.

Science.gov (United States)

Wu, Qiong; Shao, Qi; Li, Qiang; Duan, Qian; Li, Yanhui; Wang, Heng-Guo

2018-04-25

To explore a universal electrode material for the high-performance electrochemical storage of Li + , Na + , and K + ions remains a big challenge. Herein, we propose a "trinity" strategy to coat the SnO 2 hollow nanospheres using the dual carbon layer from the polydopamine-derived nitrogen-doped carbon and graphene. Thereinto, hollow structures with sufficient void space could buffer the volume expansion, whereas dual carbon-confined strategy could not only elastically prevent the aggregation of nanoparticle and ensure the structural integrity but also immensely improve the conductivity and endow high rate properties. Benefiting from the effective strategy and specific structure, the dual carbon-confined SnO 2 hollow nanosphere (denoted as G@C@SnO 2 ) can serve as the universal host material for alkali metal ions and enable their rapid and reversible storage. As expected, the resulting G@C@SnO 2 as a universal anode material shows reversible alkali-metal-ion storage with high performance. We believe this that strategy could pave the way for constructing other metal-oxide-based dual carbon-confined high-performance materials for the future energy storage applications.

Rotational cooling of polar molecules by Stark-tuned cavity resonance

International Nuclear Information System (INIS)

Ooi, C. H. Raymond

2003-01-01

A general scheme for rotational cooling of diatomic heteronuclear molecules is proposed. It uses a superconducting microwave cavity to enhance the spontaneous decay via Purcell effect. Rotational cooling can be induced by sequentially tuning each rotational transition to cavity resonance, starting from the highest transition level to the lowest one using an electric field. Electrostatic multipoles can be used to provide large confinement volume with essentially homogeneous background electric field

A Hodge dual for soldered bundles

International Nuclear Information System (INIS)

Lucas, Tiago Gribl; Pereira, J G

2009-01-01

In order to account for all possible contractions allowed by the presence of the solder form, a generalized Hodge dual is defined for the case of soldered bundles. Although for curvature the generalized dual coincides with the usual one, for torsion it gives a completely new dual definition. Starting from the standard form of a gauge Lagrangian for the translation group, the generalized Hodge dual yields precisely the Lagrangian of the teleparallel equivalent of general relativity, and consequently also the Einstein-Hilbert Lagrangian of general relativity

On R-duals and the duality principle

DEFF Research Database (Denmark)

Christensen, Ole; Stoeva, Diana

2015-01-01

. In this paper we discuss the relationship between the R-duals and a variant, called R-duals of type III, introduced in 2014. In contrast to the original R-duals, it is known that the R-duals of type III generalize the duality principle for all Gabor frames, but we believe that a smaller and more convenient...

Dual-Doppler Feasibility Study

Science.gov (United States)

Huddleston, Lisa L.

2012-01-01

When two or more Doppler weather radar systems are monitoring the same region, the Doppler velocities can be combined to form a three-dimensional (3-D) wind vector field thus providing for a more intuitive analysis of the wind field. A real-time display of the 3-D winds can assist forecasters in predicting the onset of convection and severe weather. The data can also be used to initialize local numerical weather prediction models. Two operational Doppler Radar systems are in the vicinity of Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS); these systems are operated by the 45th Space Wing (45 SW) and the National Weather Service Melbourne, Fla. (NWS MLB). Dual-Doppler applications were considered by the 45 SW in choosing the site for the new radar. Accordingly, the 45th Weather Squadron (45 WS), NWS MLB and the National Aeronautics and Space Administration tasked the Applied Meteorology Unit (AMU) to investigate the feasibility of establishing dual-Doppler capability using the two existing systems. This study investigated technical, hardware, and software requirements necessary to enable the establishment of a dual-Doppler capability. Review of the available literature pertaining to the dual-Doppler technique and consultation with experts revealed that the physical locations and resulting beam crossing angles of the 45 SW and NWS MLB radars make them ideally suited for a dual-Doppler capability. The dual-Doppler equations were derived to facilitate complete understanding of dual-Doppler synthesis; to determine the technical information requirements; and to determine the components of wind velocity from the equation of continuity and radial velocity data collected by the two Doppler radars. Analysis confirmed the suitability of the existing systems to provide the desired capability. In addition, it is possible that both 45 SW radar data and Terminal Doppler Weather Radar data from Orlando International Airport could be used to alleviate any

Dual Enrollment for High School Students

Science.gov (United States)

Edwards, Linsey; Hughes, Katherine

2011-01-01

Dual enrollment programs allow high school students to enroll in college courses and potentially earn college credit. The term concurrent enrollment is sometimes used interchangeably with dual enrollment, and sometimes to refer to a particular model of dual enrollment. In some programs, students earn high school and college credit simultaneously;…

Continuous-wave dual-wavelength operation of a distributed feedback laser diode with an external cavity using a volume Bragg grating

Science.gov (United States)

Zheng, Yujin; Sekine, Takashi; Kurita, Takashi; Kato, Yoshinori; Kawashima, Toshiyuki

2018-03-01

We demonstrate continuous-wave dual-wavelength operation of a broad-area distributed feedback (DFB) laser diode with a single external-cavity configuration. This high-power DFB laser has a narrow bandwidth (current and temperature ranges.

A Differentially Driven Dual-Polarized Dual-Wideband Complementary Antenna for 2G/3G/LTE Applications

Directory of Open Access Journals (Sweden)

Botao Feng

2014-01-01

Full Text Available A novel differentially driven dual-polarized dual-wideband complementary patch antenna with high isolation is proposed for 2G/3G/LTE applications. In order to generate dual-polarization and dual-wideband properties, a pair of biorthogonal dual-layer η-shaped tapered line feeding structures is utilized to feed two pairs of dual-layer U-shaped patches, respectively. The upper-layer U-shaped patches mainly serve the upper frequency band, while the lower-layer ones chiefly work for the lower frequency band. Besides, a horned reflector is introduced to improve radiation patterns and provide stable gain. The prototype antenna can achieve a bandwidth of 25.7% (0.78 GHz–1.01 GHz with a stable gain of 7.8±0.7 dBi for the lower band, and a bandwidth of 45.7% (1.69 GHz–2.69 GHz with a gain of 9.5±1.1 dBi for the upper band. Input isolation exceeding 30 dB has been obtained in the wide bandwidth. Thus, it can be potentially used as a base station antenna for 2G/3G/LTE networks.

Dual-core Itanium Processor

CERN Multimedia

2006-01-01

Intel’s first dual-core Itanium processor, code-named "Montecito" is a major release of Intel's Itanium 2 Processor Family, which implements the Intel Itanium architecture on a dual-core processor with two cores per die (integrated circuit). Itanium 2 is much more powerful than its predecessor. It has lower power consumption and thermal dissipation.

Correlation of iodine uptake and perfusion parameters between dual-energy CT imaging and first-pass dual-input perfusion CT in lung cancer.

Science.gov (United States)

Chen, Xiaoliang; Xu, Yanyan; Duan, Jianghui; Li, Chuandong; Sun, Hongliang; Wang, Wu

2017-07-01

To investigate the potential relationship between perfusion parameters from first-pass dual-input perfusion computed tomography (DI-PCT) and iodine uptake levels estimated from dual-energy CT (DE-CT).The pre-experimental part of this study included a dynamic DE-CT protocol in 15 patients to evaluate peak arterial enhancement of lung cancer based on time-attenuation curves, and the scan time of DE-CT was determined. In the prospective part of the study, 28 lung cancer patients underwent whole-volume perfusion CT and single-source DE-CT using 320-row CT. Pulmonary flow (PF, mL/min/100 mL), aortic flow (AF, mL/min/100 mL), and a perfusion index (PI = PF/[PF + AF]) were automatically generated by in-house commercial software using the dual-input maximum slope method for DI-PCT. For the dual-energy CT data, iodine uptake was estimated by the difference (λ) and the slope (λHU). λ was defined as the difference of CT values between 40 and 70 KeV monochromatic images in lung lesions. λHU was calculated by the following equation: λHU = |λ/(70 - 40)|. The DI-PCT and DE-CT parameters were analyzed by Pearson/Spearman correlation analysis, respectively.All subjects were pathologically proved as lung cancer patients (including 16 squamous cell carcinoma, 8 adenocarcinoma, and 4 small cell lung cancer) by surgery or CT-guided biopsy. Interobserver reproducibility in DI-PCT (PF, AF, PI) and DE-CT (λ, λHU) were relatively good to excellent (intraclass correlation coefficient [ICC]Inter = 0.8726-0.9255, ICCInter = 0.8179-0.8842; ICCInter = 0.8881-0.9177, ICCInter = 0.9820-0.9970, ICCInter = 0.9780-0.9971, respectively). Correlation coefficient between λ and AF, and PF were as follows: 0.589 (P input CT perfusion analysis method can be applied to assess blood supply of lung cancer patients. Preliminary results demonstrated that the iodine uptake relevant parameters derived from DE-CT significantly correlated with perfusion

A 4 tonne demonstrator for large-scale dual-phase liquid argon time projection chambers arXiv

CERN Document Server

Aimard, B.; Asaadi, J.; Auger, M.; Aushev, V.; Autiero, D.; Badoi, M.M.; Balaceanu, A.; Balik, G.; Balleyguier, L.; Bechetoille, E.; Belver, D.; Blebea-Apostu, A.M.; Bolognesi, S.; Bordoni, S.; Bourgeois, N.; Bourguille, B.; Bremer, J.; Brown, G.; Brunetti, G.; Caiulo, D.; Calin, M.; Calvo, E.; Campanelli, M.; Cankocak, K.; Cantini, C.; Carlus, B.; Cautisanu, B.M.; Chalifour, M.; Chappuis, A.; Charitonidis, N.; Chatterjee, A.; Chiriacescu, A.; Chiu, P.; Conforti, S.; Cotte, Ph.; Crivelli, P.; Cuesta, C.; Dawson, J.; De Bonis, I.; De La Taille, C.; Delbart, A.; Desforge, D.; Di Luise, S.; Dimitru, B.S.; Doizon, F.; Drancourt, C.; Duchesneau, D.; Dulucq, F.; Dumarchez, J.; Duval, F.; Emery, S.; Ereditato, A.; Esanu, T.; Falcone, A.; Fusshoeller, K.; Gallego-Ros, A.; Galymov, V.; Geffroy, N.; Gendotti, A.; Gherghel-Lascu, M.; Giganti, C.; Gil-Botella, I.; Girerd, C.; Gomoiu, M.C.; Gorodetzky, P.; Hamada, E.; Hanni, R.; Hasegawa, T.; Holin, A.; Horikawa, S.; Ikeno, M.; Jiménez, S.; Jipa, A.; Karolak, M.; Karyotakis, Y.; Kasai, S.; Kasami, K.; Kishishita, T.; Kreslo, I.; Kryn, D.; Lastoria, C.; Lazanu, I.; Lehmann-Miotto, G.; Lira, N.; Loo, K.; Lorca, D.; Lutz, P.; Lux, T.; Maalampi, J.; Maire, G.; Maki, M.; Manenti, L.; Margineanu, R.M.; Marteau, J.; Martin-Chassard, G.; Mathez, H.; Mazzucato, E.; Misitano, G.; Mitrica, B.; Mladenov, D.; Molina Bueno, L.; Moreno Martínez, C.; Mols, J.Ph.; Mosu, T.S.; Mu, W.; Munteanu, A.; Murphy, S.; Nakayoshi, K.; Narita, S.; Navas-Nicolás, D.; Negishi, K.; Nessi, M.; Niculescu-Oglinzanu, M.; Nita, L.; Noto, F.; Noury, A.; Onishchuk, Y.; Palomares, C.; Parvu, M.; Patzak, T.; Pénichot, Y.; Pennacchio, E.; Periale, L.; Pessard, H.; Pietropaolo, F.; Piret, Y.; Popov, B.; Pugnere, D.; Radics, B.; Redondo, D.; Regenfus, C.; Remoto, A.; Resnati, F.; Rigaut, Y.A.; Ristea, C.; Rubbia, A.; Saftoiu, A.; Sakashita, K.; Sanchez, F.; Santos, C.; Scarpelli, A.; Schloesser, C.; Scotto Lavina, L.; Sendai, K.; Sergiampietri, F.; Shahsavarani, S.; Shoji, M.; Sinclair, J.; Soto-Oton, J.; Stanca, D.L.; Stefan, D.; Stroescu, P.; Sulej, R.; Tanaka, M.; Toboaru, V.; Tonazzo, A.; Tromeur, W.; Trzaska, W.H.; Uchida, T.; Vannucci, F.; Vasseur, G.; Verdugo, A.; Viant, T.; Vihonen, S.; Vilalte, S.; Weber, M.; Wu, S.; Yu, J.; Zambelli, L.; Zito, M.

A 10 kilo-tonne dual-phase liquid argon TPC is one of the detector options considered for the Deep Underground Neutrino Experiment (DUNE). The detector technology relies on amplification of the ionisation charge in ultra-pure argon vapour and others several advantages compared to the traditional single-phase liquid argon TPCs. A 4.2 tonne dual-phase liquid argon TPC prototype, the largest of its kind, with an active volume of 3 x1x1 m^3 has been constructed and operated at CERN. In this paper we describe in detail the experimental setup and detector components as well as report on the operation experience. We also present the first results on the achieved charge amplification, prompt scintillation and electroluminiscence detection, and purity of the liquid argon from analyses of a collected sample of cosmic ray muons.

GPM GROUND VALIDATION DUAL-FREQUENCY DUAL-POLARIZED DOPPLER RADAR (D3R) IFLOODS V1

Data.gov (United States)

National Aeronautics and Space Administration — The GPM Ground Validation Dual-frequency Dual-polarized Doppler Radar (D3R) IFloodS data set contain radar reflectivity and doppler velocity measurements. The D3R...

Preliminary study of single contrast enhanced dual energy heart imaging using dual-source CT

International Nuclear Information System (INIS)

Peng Jin; Zhang Longjiang; Zhou Changsheng; Lu Guangming; Ma Yan; Gu Haifeng

2009-01-01

Objective: To evaluate the feasibility and preliminary applications of single contrast enhanced dual energy heart imaging using dual-source CT (DSCT). Methods: Thirty patients underwent dual energy heart imaging with DSCT, of which 6 cases underwent SPECT or DSA within one week. Two experienced radiologists assessed image quality of coronary arteries and iodine map of myocardium. and correlated the coronary artery stenosis with the perfusion distribution of iodine map. Results: l00% (300/300) segments reached diagnostic standards. The mean score of image for all patients was 4.68±0.57. Mural coronary artery was present in 10 segments in S cases, atherosclerotic plaques in 32 segments in 12 cases, of which 20 segments having ≥50% stenosis, 12 segments ≤50% stenosis; dual energy CT coronary angiography was consistent with the DSA in 3 patients. 37 segmental perfusion abnormalities on iodine map were found in 15 cases, including 28 coronary blood supply segment narrow segment and 9 no coronary stenosis (including three negative segments in SPECD. Conclusion: Single contrast enhanced dual energy heart imaging can provide good coronary artery and myocardium perfusion images in the patients with appropriate heart rate, which has a potential to be used in the clinic and further studies are needed. (authors)

Dual education and industrial cooperation in electrical engineering

Science.gov (United States)

Váradiné Szarka, A.

2016-11-01

Dual education in higher education is a new system in Hungary introduced by Mercedes Benz with cooperation of Kecskemet College. In the new system companies support certain number of students and provide them strong practical education in their field. Students applying successfully for dual education study together with non-dual students at the university, so they go through the same university courses as their non-dual colleagues, but while non-dual students’ academic year includes 2×14 weeks active semester and 2×6 weeks exam session, all over 40 weeks, dual students have 48 working weeks including study at the university and practicing at the company. The main question of the success which one is the most effective model to be applied. This paper summarises 2 models of dual education with their advantages and disadvantages and also it presents practical realization at the University of Debrecen with special attention to measurement and instrumentation. Dual education in BSc level electrical engineering course cooperates with 6 multinational companies of the region in four specialization. Dual education also has great impact to the modernisation of engineering education. Detailed study of dual education in field of instrumentation and measurement is provided in the paper.

Dual energy CT: New horizon in medical imaging

Energy Technology Data Exchange (ETDEWEB)

Goo, Hyun Woo [Dept. of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Goo, Jin Mo [Dept. of Radiology, Seoul National University College of Medicine, Seoul (Korea, Republic of)

2017-08-01

Dual-energy CT has remained underutilized over the past decade probably due to a cumbersome workflow issue and current technical limitations. Clinical radiologists should be made aware of the potential clinical benefits of dual-energy CT over single-energy CT. To accomplish this aim, the basic principle, current acquisition methods with advantages and disadvantages, and various material-specific imaging methods as clinical applications of dual-energy CT should be addressed in detail. Current dual-energy CT acquisition methods include dual tubes with or without beam filtration, rapid voltage switching, dual-layer detector, split filter technique, and sequential scanning. Dual-energy material-specific imaging methods include virtual monoenergetic or monochromatic imaging, effective atomic number map, virtual non-contrast or unenhanced imaging, virtual non-calcium imaging, iodine map, inhaled xenon map, uric acid imaging, automatic bone removal, and lung vessels analysis. In this review, we focus on dual-energy CT imaging including related issues of radiation exposure to patients, scanning and post-processing options, and potential clinical benefits mainly to improve the understanding of clinical radiologists and thus, expand the clinical use of dual-energy CT; in addition, we briefly describe the current technical limitations of dual-energy CT and the current developments of photon-counting detector.

Dual-Energy CT: New Horizon in Medical Imaging.

Science.gov (United States)

Goo, Hyun Woo; Goo, Jin Mo

2017-01-01

Dual-energy CT has remained underutilized over the past decade probably due to a cumbersome workflow issue and current technical limitations. Clinical radiologists should be made aware of the potential clinical benefits of dual-energy CT over single-energy CT. To accomplish this aim, the basic principle, current acquisition methods with advantages and disadvantages, and various material-specific imaging methods as clinical applications of dual-energy CT should be addressed in detail. Current dual-energy CT acquisition methods include dual tubes with or without beam filtration, rapid voltage switching, dual-layer detector, split filter technique, and sequential scanning. Dual-energy material-specific imaging methods include virtual monoenergetic or monochromatic imaging, effective atomic number map, virtual non-contrast or unenhanced imaging, virtual non-calcium imaging, iodine map, inhaled xenon map, uric acid imaging, automatic bone removal, and lung vessels analysis. In this review, we focus on dual-energy CT imaging including related issues of radiation exposure to patients, scanning and post-processing options, and potential clinical benefits mainly to improve the understanding of clinical radiologists and thus, expand the clinical use of dual-energy CT; in addition, we briefly describe the current technical limitations of dual-energy CT and the current developments of photon-counting detector.

Novel CFT duals for extreme black holes

International Nuclear Information System (INIS)

Chen Bin; Zhang Jiaju

2012-01-01

In this paper, we study the CFT duals for extreme black holes in the stretched horizon formalism. We consider the extremal RN, Kerr-Newman-AdS-dS, as well as the higher dimensional Kerr-AdS-dS black holes. In all these cases, we reproduce the well-established CFT duals. Actually we show that for stationary extreme black holes, the stretched horizon formalism always gives rise to the same dual CFT pictures as the ones suggested by ASG of corresponding near horizon geometries. Furthermore, we propose new CFT duals for 4D Kerr-Newman-AdS-dS and higher dimensional Kerr-AdS-dS black holes. We find that every dual CFT is defined with respect to a rotation in certain angular direction, along which the translation defines a U(1) Killing symmetry. In the presence of two sets of U(1) symmetry, the novel CFT duals are generated by the modular group SL(2,Z), and for n sets of U(1) symmetry there are general CFT duals generated by T-duality group SL(n,Z).

An overmoded relativistic backward wave oscillator with efficient dual-mode operation

International Nuclear Information System (INIS)

Xiao, Renzhen; Li, Jiawei; Bai, Xianchen; Song, Zhimin; Teng, Yan; Ye, Hu; Li, Xiaoze; Sun, Jun; Chen, Changhua; Zhang, Xiaowei

2014-01-01

A dual-mode operation mechanism in an overmoded relativistic backward wave oscillator is presented. The electron beam interacts with the −1st space harmonic of TM 01 mode synchronously in the slow wave structure. Then the backward propagating TM 01 mode is converted to the forward propagating TM 02 mode. As the phase velocity of the volume harmonic of TM 02 mode is about twice that of the surface harmonic of TM 01 mode, the TM 02 mode also plays an important role in the high-power microwave generation. Particle-in-cell simulation shows that an efficiency of 48% and a significant improvement of the power capacity have been obtained

Are factors related to dual-task performance in people with Parkinson's disease dependent on the type of dual task?

Science.gov (United States)

Strouwen, Carolien; Molenaar, Esther A L M; Keus, Samyra H J; Münks, Liesbeth; Heremans, Elke; Vandenberghe, Wim; Bloem, Bastiaan R; Nieuwboer, Alice

2016-02-01

Impaired dual-task performance significantly impacts upon functional mobility in people with Parkinson's disease (PD). The aim of this study was to identify determinants of dual-task performance in people with PD in three different dual tasks to assess their possible task-dependency. We recruited 121 home-dwelling patients with PD (mean age 65.93 years; mean disease duration 8.67 years) whom we subjected to regular walking (control condition) and to three dual-task conditions: walking combined with a backwards Digit Span task, an auditory Stroop task and a Mobile Phone task. We measured dual-task gait velocity using the GAITRite mat and dual-task reaction times and errors on the concurrent tasks as outcomes. Motor, cognitive and descriptive variables which correlated to dual-task performance (p task gait velocity and executive function, tested by the alternating intake test, was significantly associated with gait velocity during the Digit Span (R(2) = 0.65; p task (R(2) = 0.62; p task. Age was a surplus determinant of gait velocity while using a mobile phone. Single-task gait velocity and executive function as measured by a verbal fluency switching task were independent determinants of dual-task gait performance in people with PD. In contrast to expectation, these factors were the same across different tasks, supporting the robustness of the findings. Future study needs to determine whether these factors predict dual-task abnormalities prospectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

Image quality optimization and evaluation of linearly mixed images in dual-source, dual-energy CT

International Nuclear Information System (INIS)

Yu Lifeng; Primak, Andrew N.; Liu Xin; McCollough, Cynthia H.

2009-01-01

In dual-source dual-energy CT, the images reconstructed from the low- and high-energy scans (typically at 80 and 140 kV, respectively) can be mixed together to provide a single set of non-material-specific images for the purpose of routine diagnostic interpretation. Different from the material-specific information that may be obtained from the dual-energy scan data, the mixed images are created with the purpose of providing the interpreting physician a single set of images that have an appearance similar to that in single-energy images acquired at the same total radiation dose. In this work, the authors used a phantom study to evaluate the image quality of linearly mixed images in comparison to single-energy CT images, assuming the same total radiation dose and taking into account the effect of patient size and the dose partitioning between the low-and high-energy scans. The authors first developed a method to optimize the quality of the linearly mixed images such that the single-energy image quality was compared to the best-case image quality of the dual-energy mixed images. Compared to 80 kV single-energy images for the same radiation dose, the iodine CNR in dual-energy mixed images was worse for smaller phantom sizes. However, similar noise and similar or improved iodine CNR relative to 120 kV images could be achieved for dual-energy mixed images using the same total radiation dose over a wide range of patient sizes (up to 45 cm lateral thorax dimension). Thus, for adult CT practices, which primarily use 120 kV scanning, the use of dual-energy CT for the purpose of material-specific imaging can also produce a set of non-material-specific images for routine diagnostic interpretation that are of similar or improved quality relative to single-energy 120 kV scans.

Least-squares dual characterization for ROI assessment in emission tomography

International Nuclear Information System (INIS)

Ben Bouallègue, F; Mariano-Goulart, D; Crouzet, J F; Dubois, A; Buvat, I

2013-01-01

Our aim is to describe an original method for estimating the statistical properties of regions of interest (ROIs) in emission tomography. Drawn upon the works of Louis on the approximate inverse, we propose a dual formulation of the ROI estimation problem to derive the ROI activity and variance directly from the measured data without any image reconstruction. The method requires the definition of an ROI characteristic function that can be extracted from a co-registered morphological image. This characteristic function can be smoothed to optimize the resolution-variance tradeoff. An iterative procedure is detailed for the solution of the dual problem in the least-squares sense (least-squares dual (LSD) characterization), and a linear extrapolation scheme is described to compensate for sampling partial volume effect and reduce the estimation bias (LSD-ex). LSD and LSD-ex are compared with classical ROI estimation using pixel summation after image reconstruction and with Huesman's method. For this comparison, we used Monte Carlo simulations (GATE simulation tool) of 2D PET data of a Hoffman brain phantom containing three small uniform high-contrast ROIs and a large non-uniform low-contrast ROI. Our results show that the performances of LSD characterization are at least as good as those of the classical methods in terms of root mean square (RMS) error. For the three small tumor regions, LSD-ex allows a reduction in the estimation bias by up to 14%, resulting in a reduction in the RMS error of up to 8.5%, compared with the optimal classical estimation. For the large non-specific region, LSD using appropriate smoothing could intuitively and efficiently handle the resolution-variance tradeoff. (paper)

Least-squares dual characterization for ROI assessment in emission tomography

Science.gov (United States)

Ben Bouallègue, F.; Crouzet, J. F.; Dubois, A.; Buvat, I.; Mariano-Goulart, D.

2013-06-01

Our aim is to describe an original method for estimating the statistical properties of regions of interest (ROIs) in emission tomography. Drawn upon the works of Louis on the approximate inverse, we propose a dual formulation of the ROI estimation problem to derive the ROI activity and variance directly from the measured data without any image reconstruction. The method requires the definition of an ROI characteristic function that can be extracted from a co-registered morphological image. This characteristic function can be smoothed to optimize the resolution-variance tradeoff. An iterative procedure is detailed for the solution of the dual problem in the least-squares sense (least-squares dual (LSD) characterization), and a linear extrapolation scheme is described to compensate for sampling partial volume effect and reduce the estimation bias (LSD-ex). LSD and LSD-ex are compared with classical ROI estimation using pixel summation after image reconstruction and with Huesman's method. For this comparison, we used Monte Carlo simulations (GATE simulation tool) of 2D PET data of a Hoffman brain phantom containing three small uniform high-contrast ROIs and a large non-uniform low-contrast ROI. Our results show that the performances of LSD characterization are at least as good as those of the classical methods in terms of root mean square (RMS) error. For the three small tumor regions, LSD-ex allows a reduction in the estimation bias by up to 14%, resulting in a reduction in the RMS error of up to 8.5%, compared with the optimal classical estimation. For the large non-specific region, LSD using appropriate smoothing could intuitively and efficiently handle the resolution-variance tradeoff.

Frequency and characteristics of dual pathology in patients with lesional epilepsy.

Science.gov (United States)

Cendes, F; Cook, M J; Watson, C; Andermann, F; Fish, D R; Shorvon, S D; Bergin, P; Free, S; Dubeau, F; Arnold, D L

1995-11-01

We studied 167 patients who had identifiable lesions and temporal or extratemporal partial epilepsy. Pathology included neuronal migration disorders (NMDs) (48), low-grade tumors (52), vascular malformations (34), porencephalic cysts (16), and gliotic lesions as a result of cerebral insults early in life (17). MRI volumetric studies using thin (1.5- or 3-mm) coronal images were performed in all patients and in 44 age-matched normal controls. An atrophic hippocampal formation (HF), indicating dual pathology, was present in 25 patients (15%). Abnormal HF volumes were present in those with lesions involving temporal (17%) but also extratemporal (14%) areas. Age at onset and duration of epilepsy did not influence the presence of HF atrophy. However, febrile seizures in early childhood were more frequently, although not exclusively, found in patients with hippocampal atrophy. The frequency of hippocampal atrophy in our patients with low-grade tumors (2%) and vascular lesions (9%) was low. Dual pathology was far more common in patients with NMDs (25%), porencephalic cysts (31%), and reactive gliosis (23.5%). Some structural lesions, such as NMDs, are more likely to be associated with hippocampal atrophy, independent of the distance of the lesion from the HF. In other types of lesions, such as vascular malformations, dual pathology was found when the lesion was close to the HF. A common pathogenic mechanism during pre- or perinatal development may explain the occurrence of concomitant mesial temporal sclerosis and other structural lesions because of either (1) associated developmental abnormalities or (2) predisposition to prolonged febrile convulsions.(ABSTRACT TRUNCATED AT 250 WORDS)

Interference of Spin-2 Self-Dual Modes

OpenAIRE

Ilha, Anderson; Wotzasek, Clovis

2001-01-01

We study the effects of interference between the self-dual and anti self-dual massive modes of the linearized Einstein-Chern-Simons topological gravity. The dual models to be used in the interference process are carefully analyzed with special emphasis on their propagating spectrum. We identify the opposite dual aspects, necessary for the application of the interference formalism on this model. The soldered theory so obtained displays explicitly massive modes of the Proca type. It may also be...

Limitations in dual-task performance

NARCIS (Netherlands)

Pannebakker, Merel Mathilde

2009-01-01

In this thesis, the effect of information-processing overload on working-memory dependent information processing was examined using dual-task paradigms. The experiments described strengthen the importance of a functional explanation for dual-task limitations. First, it showed evidence for a unified

Dual hit lipopolysaccharide & oleic acid combination induced rat model of acute lung injury/acute respiratory distress syndrome.

Science.gov (United States)

Hagawane, T N; Gaikwad, R V; Kshirsagar, N A

2016-05-01

Despite advances in therapy and overall medical care, acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) management remains a problem. Hence the objective of this study was to develop a rat model that mimics human ALI/ARDS. Four groups of Wistar rats, 48 per group were treated with (i) intratracheal (IT) lipopolysaccharide (LPS) (5 mg/kg) dissolved in normal saline (NS), (ii) intravenous (iv) oleic acid (OA) (250 μl/kg) suspension in bovine serum albumin (BSA), (iii) dual hit: IT LPS (2 mg/kg) dissolved in NS and iv OA (100 μl/kg) and (iv) control group: IT NS and iv BSA. From each group at set periods of time various investigations like chest x-rays, respiratory rate (RR), tidal volume (TV), total cell count, differential cell count, total protein count and cytokine levels in bronchoalveolar lavage fluid (BALF), lung wet/dry weight ratio and histopathological examination were done. It was noted that the respiratory rate, and tumour necrosis factor-α (TNF-α) levels were significantly higher at 4 h in the dual hit group as compared to LPS, OA and control groups. Interleukin-6 (IL-6) levels were significantly higher in the dual hit group as compared to LPS at 8 and 24 h, OA at 8 h and control (at all time intervals) group. IL-1β levels were significantly higher in LPS and dual hit groups at all time intervals, but not in OA and control groups. The injury induced in dual hit group was earlier and more sustained as compared to LPS and OA alone. The lung pathology and changes in respiration functions produced by the dual hit model were closer to the diagnostic criteria of ALI/ARDS in terms of clinical manifestations and pulmonary injury and the injury persisted longer as compared to LPS and OA single hit model. Therefore, the ARDS model produced by the dual hit method was closer to the diagnostic criteria of ARDS in terms of clinical manifestations and pulmonary injury.

Aerial Triangulation Close-range Images with Dual Quaternion

Directory of Open Access Journals (Sweden)

SHENG Qinghong

2015-05-01

Full Text Available A new method for the aerial triangulation of close-range images based on dual quaternion is presented. Using dual quaternion to represent the spiral screw motion of the beam in the space, the real part of dual quaternion represents the angular elements of all the beams in the close-range area networks, the real part and the dual part of dual quaternion represents the line elements corporately. Finally, an aerial triangulation adjustment model based on dual quaternion is established, and the elements of interior orientation and exterior orientation and the object coordinates of the ground points are calculated. Real images and large attitude angle simulated images are selected to run the experiments of aerial triangulation. The experimental results show that the new method for the aerial triangulation of close-range images based on dual quaternion can obtain higher accuracy.

Performance Enhancements Under Dual-task Conditions

Science.gov (United States)

Kramer, A. F.; Wickens, C. D.; Donchin, E.

1984-01-01

Research on dual-task performance has been concerned with delineating the antecedent conditions which lead to dual-task decrements. Capacity models of attention, which propose that a hypothetical resource structure underlies performance, have been employed as predictive devices. These models predict that tasks which require different processing resources can be more successfully time shared than tasks which require common resources. The conditions under which such dual-task integrality can be fostered were assessed in a study in which three factors likely to influence the integrality between tasks were manipulated: inter-task redundancy, the physical proximity of tasks and the task relevant objects. Twelve subjects participated in three experimental sessions in which they performed both single and dual-tasks. The primary task was a pursuit step tracking task. The secondary tasks required the discrimination between different intensities or different spatial positions of a stimulus. The results are discussed in terms of a model of dual-task integrality.

Evaluation of Myc Gene Amplification in Prostate Cancer Using a Dual Color Chromogenic in-Situ Hybridization (Dual CISH) Assay

OpenAIRE

Daniel Lerda; Marta Cabrera; Jorge Flores; Luis Gutierrez; Armando Chierichetti; Martin Revol; Hernan Garcia Onto

2013-01-01

Objetive: The overall purpose of the study was to demonstrate applicability of the Dako dual-color chromogenic in situ hybridization (CISH) assay (DAKO Denmark, Glostrup) with respect to fluorescence in situ hybridization (FISH) probes MYC-C. Methods: MYC gene amplification by FISH and Dako dual-color CISH Results: The study showed that the dual-color CISH assay can convert Texas red and fluorescein isothiocyanate (FITC) signals into chromogenic signals. The dual –color CISH assay was p...

Dual-Mode Combustor

Science.gov (United States)

Trefny, Charles J (Inventor); Dippold, Vance F (Inventor)

2013-01-01

A new dual-mode ramjet combustor used for operation over a wide flight Mach number range is described. Subsonic combustion mode is usable to lower flight Mach numbers than current dual-mode scramjets. High speed mode is characterized by supersonic combustion in a free-jet that traverses the subsonic combustion chamber to a variable nozzle throat. Although a variable combustor exit aperture is required, the need for fuel staging to accommodate the combustion process is eliminated. Local heating from shock-boundary-layer interactions on combustor walls is also eliminated.

Dual Headquarters Involvement in Multibusiness Firms

DEFF Research Database (Denmark)

Nell, Phillip Christopher; Kappen, Philip; Dellestrand, Henrik

The strategy literature has shown that headquarters involve themselves into subsidiary operations to add value. Yet, little is known about the extent to which multiple headquarters do so. Therefore, we investigate antecedents of corporate and divisional headquarters’ involvement in innovation...... development projects of subsidiaries. Analyses of 85 innovation development projects reveal that dual innovation importance (innovation that is important for the division and the rest of the firm), and dual dual embeddedness (innovating subsidiary is embedded both within the division and in the rest...... of the firm) lead to greater dual headquarters involvement, especially when the innovation development network is large. The results contribute to the literature on complex parenting and theory of selective headquarters involvement....

The design of a lead-bismuth target system with a dual injection tube

International Nuclear Information System (INIS)

Cho, C.H.; Kim, Y.; Song, T.Y.; Park, W.S.

2005-01-01

A spallation target system is a key component to be developed for an accelerator driven system (ADS). It is known that a 15 ∼ 25 MW spallation target is required for a practical 1000 MWth ADS. The design of a 20 MW spallation target is very challenging because more than 60% of the beam power is deposited as heat in a small volume of the target system. In the present work, a numerical design study was performed to obtain the optimal design parameters for a 20 MW spallation target for a 1000 MW ADS. A dual injection tube was proposed for the reduction of the LBE flow rate at the target channel. The results of the present study show that a 30 cm wide proton beam with a uniform beam distribution should be adopted for the spallation target of a 20 MW power. When the dual LBE injection tube is employed, the LBE flow rate could be reduced by a factor of 4 without reducing the maximum allowable beam current. (authors)

[Dual pathology].

Science.gov (United States)

Rougier, A

2008-05-01

Dual pathology is defined as the association of two potentially epileptogenic lesions, hippocampal (sclerosis, neuronal loss) and extrahippocampal (temporal or extratemporal). Epileptic activity may be generated by either lesion and the relative importance of every lesion's epileptogenicity conditions the surgical strategy adopted. Most frequently associated with hippocampal sclerosis are cortical dysplasias. The common physiopathology of the two lesions is not clearly established. Extrahippocampal lesions may be undetectable on MRI (microdysgenesis, for example) and ictal discharge patterns may vary among dual pathology patients. The surgical strategy depends on the location of the extrahippocampal lesion and its relative role in seizure generation; however, reported surgical results suggest that simultaneous resection of mesial temporal structures along with the extrahippocampal lesion should be performed.

A generalized strategy for designing (19)F/(1)H dual-frequency MRI coil for small animal imaging at 4.7 Tesla.

Science.gov (United States)

Hu, Lingzhi; Hockett, Frank D; Chen, Junjie; Zhang, Lei; Caruthers, Shelton D; Lanza, Gregory M; Wickline, Samuel A

2011-07-01

To propose and test a universal strategy for building (19) F/(1) H dual-frequency RF coil that permits multiple coil geometries. The feasibility to design (19) F/(1) H dual-frequency RF coil based on coupled resonator model was investigated. A series capacitive matching network enables robust impedance matching for both harmonic oscillating modes of the coupled resonator. Two typical designs of (19) F/(1) H volume coils (birdcage and saddle) at 4.7T were implemented and evaluated with electrical bench test and in vivo (19) F/(1) H dual-nuclei imaging. For various combinations of internal resistances of the sample coil and secondary resonator, numerical solutions for the tunable capacitors to optimize impedance matching were obtained using a root-seeking program. Identical and homogeneous B1 field distribution at (19) F and (1) H frequencies were observed in bench test and phantom image. Finally, in vivo mouse imaging confirmed the sensitivity and homogeneity of the (19) F/(1) H dual-frequency coil design. A generalized strategy for designing (19) F/(1) H dual-frequency coils based on the coupled resonator approach was developed and validated. A unique feature of this design is that it preserves the B1 field homogeneity of the RF coil at both resonant frequencies. Thus it minimizes the susceptibility effect on image co-registration. Copyright © 2011 Wiley-Liss, Inc.

3D modeling of dual-gate FinFET.

Science.gov (United States)

Mil'shtein, Samson; Devarakonda, Lalitha; Zanchi, Brian; Palma, John

2012-11-13

The tendency to have better control of the flow of electrons in a channel of field-effect transistors (FETs) did lead to the design of two gates in junction field-effect transistors, field plates in a variety of metal semiconductor field-effect transistors and high electron mobility transistors, and finally a gate wrapping around three sides of a narrow fin-shaped channel in a FinFET. With the enhanced control, performance trends of all FETs are still challenged by carrier mobility dependence on the strengths of the electrical field along the channel. However, in cases when the ratio of FinFET volume to its surface dramatically decreases, one should carefully consider the surface boundary conditions of the device. Moreover, the inherent non-planar nature of a FinFET demands 3D modeling for accurate analysis of the device performance. Using the Silvaco modeling tool with quantization effects, we modeled a physical FinFET described in the work of Hisamoto et al. (IEEE Tran. Elec. Devices 47:12, 2000) in 3D. We compared it with a 2D model of the same device. We demonstrated that 3D modeling produces more accurate results. As 3D modeling results came close to experimental measurements, we made the next step of the study by designing a dual-gate FinFET biased at Vg1 >Vg2. It is shown that the dual-gate FinFET carries higher transconductance than the single-gate device.

Dual Coding and Bilingual Memory.

Science.gov (United States)

Paivio, Allan; Lambert, Wallace

1981-01-01

Describes study which tested a dual coding approach to bilingual memory using tasks that permit comparison of the effects of bilingual encoding with verbal-nonverbal dual encoding items. Results provide strong support for a version of the independent or separate stories view of bilingual memory. (Author/BK)

Switchable dual-wavelength single-longitudinal-mode erbium fiber laser utilizing a dual-ring scheme with a saturable absorber

Science.gov (United States)

Yang, Zi-Qing; Huang, Tzu-Jung; Chang, Yao-Jen; Yeh, Chien-Hung; Chow, Chi-Wai; Chen, Jing-Heng; Chen, Kun-Huang

2018-06-01

In this work, we propose and demonstrate a switchable dual-wavelength erbium-doped fiber (EDF) ring laser with stable single-longitudinal-mode (SLM) output. Here, a dual-ring (DR) structure with an unpumped EDF of 2 m is designed to achieve SLM oscillation. Five fiber Bragg gratings (FBGs) are applied in the laser cavity serving as the reflective element to generate different dual-wavelength outputs. In the measurement, six sets of generated dual-wavelengths with various mode-spacing (Δλ) can be achieved via the five FBGs. Additionally, the stability performance of the proposed EDF DR laser is also demonstrated.

A dual-view digital tomosynthesis imaging technique for improved chest imaging

Energy Technology Data Exchange (ETDEWEB)

Zhong, Yuncheng; Lai, Chao-Jen; Wang, Tianpeng; Shaw, Chris C., E-mail: cshaw@mdanderson.org [Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77054 (United States)

2015-09-15

Purpose: Digital tomosynthesis (DTS) has been shown to be useful for reducing the overlapping of abnormalities with anatomical structures at various depth levels along the posterior–anterior (PA) direction in chest radiography. However, DTS provides crude three-dimensional (3D) images that have poor resolution in the lateral view and can only be displayed with reasonable quality in the PA view. Furthermore, the spillover of high-contrast objects from off-fulcrum planes generates artifacts that may impede the diagnostic use of the DTS images. In this paper, the authors describe and demonstrate the use of a dual-view DTS technique to improve the accuracy of the reconstructed volume image data for more accurate rendition of the anatomy and slice images with improved resolution and reduced artifacts, thus allowing the 3D image data to be viewed in views other than the PA view. Methods: With the dual-view DTS technique, limited angle scans are performed and projection images are acquired in two orthogonal views: PA and lateral. The dual-view projection data are used together to reconstruct 3D images using the maximum likelihood expectation maximization iterative algorithm. In this study, projection images were simulated or experimentally acquired over 360° using the scanning geometry for cone beam computed tomography (CBCT). While all projections were used to reconstruct CBCT images, selected projections were extracted and used to reconstruct single- and dual-view DTS images for comparison with the CBCT images. For realistic demonstration and comparison, a digital chest phantom derived from clinical CT images was used for the simulation study. An anthropomorphic chest phantom was imaged for the experimental study. The resultant dual-view DTS images were visually compared with the single-view DTS images and CBCT images for the presence of image artifacts and accuracy of CT numbers and anatomy and quantitatively compared with root-mean-square-deviation (RMSD) values

Data sharing and dual-use issues.

Science.gov (United States)

Bezuidenhout, Louise

2013-03-01

The concept of dual-use encapsulates the potential for well-intentioned, beneficial scientific research to also be misused by a third party for malicious ends. The concept of dual-use challenges scientists to look beyond the immediate outcomes of their research and to develop an awareness of possible future (mis)uses of scientific research. Since 2001 much attention has been paid to the possible need to regulate the dual-use potential of the life sciences. Regulation initiatives fall under two broad categories-those that develop the ethical education of scientists and foster an awareness and responsibility of dual-use issues, and those which assess the regulation of information being generated by current research. Both types of initiatives are premised on a cautious, risk-adverse philosophy which advocates careful examination of all future endpoints of research endeavors. This caution advocated within initiatives such as pre-publication review of journal articles contrasts to the obligation to share underpinning data sharing discussions. As the dual-use debate has yet to make a significant impact on data sharing discussions (and vice versa) it is possible that these two areas of knowledge control may present areas of ethical conflict for scientists, and thus need to be more closely examined. This paper examines the tension between the obligation to share exemplified by data sharing principles and the concerns raised by the risk-cautious culture of the dual-use debates. The paper concludes by reflecting on the issues of responsibility as raised by dual-use as relating to data sharing, such as the chain of custody for shared data.

Unraveling Executive Functioning in Dual Diagnosis.

Science.gov (United States)

Duijkers, Judith C L M; Vissers, Constance Th W M; Egger, Jos I M

2016-01-01

In mental health, the term dual-diagnosis is used for the co-occurrence of Substance Use Disorder (SUD) with another mental disorder. These co-occurring disorders can have a shared cause, and can cause/intensify each other's expression. Forming a threat to health and society, dual-diagnosis is associated with relapses in addiction-related behavior and a destructive lifestyle. This is due to a persistent failure to control impulses and the maintaining of inadequate self-regulatory behavior in daily life. Thus, several aspects of executive functioning like inhibitory, shifting and updating processes seem impaired in dual-diagnosis. Executive (dys-)function is currently even seen as a shared underlying key component of most mental disorders. However, the number of studies on diverse aspects of executive functioning in dual-diagnosis is limited. In the present review, a systematic overview of various aspects of executive functioning in dual-diagnosis is presented, striving for a prototypical profile of patients with dual-diagnosis. Looking at empirical results, inhibitory and shifting processes appear to be impaired for SUD combined with schizophrenia, bipolar disorder or cluster B personality disorders. Studies involving updating process tasks for dual-diagnosis were limited. More research that zooms in to the full diversity of these executive functions is needed in order to strengthen these findings. Detailed insight in the profile of strengths and weaknesses that underlies one's behavior and is related to diagnostic classifications, can lead to tailor-made assessment and indications for treatment, pointing out which aspects need attention and/or training in one's self-regulative abilities.

Group contribution methodology based on the statistical associating fluid theory for heteronuclear molecules formed from Mie segments.

Science.gov (United States)

Papaioannou, Vasileios; Lafitte, Thomas; Avendaño, Carlos; Adjiman, Claire S; Jackson, George; Müller, Erich A; Galindo, Amparo

2014-02-07

A generalization of the recent version of the statistical associating fluid theory for variable range Mie potentials [Lafitte et al., J. Chem. Phys. 139, 154504 (2013)] is formulated within the framework of a group contribution approach (SAFT-γ Mie). Molecules are represented as comprising distinct functional (chemical) groups based on a fused heteronuclear molecular model, where the interactions between segments are described with the Mie (generalized Lennard-Jonesium) potential of variable attractive and repulsive range. A key feature of the new theory is the accurate description of the monomeric group-group interactions by application of a high-temperature perturbation expansion up to third order. The capabilities of the SAFT-γ Mie approach are exemplified by studying the thermodynamic properties of two chemical families, the n-alkanes and the n-alkyl esters, by developing parameters for the methyl, methylene, and carboxylate functional groups (CH3, CH2, and COO). The approach is shown to describe accurately the fluid-phase behavior of the compounds considered with absolute average deviations of 1.20% and 0.42% for the vapor pressure and saturated liquid density, respectively, which represents a clear improvement over other existing SAFT-based group contribution approaches. The use of Mie potentials to describe the group-group interaction is shown to allow accurate simultaneous descriptions of the fluid-phase behavior and second-order thermodynamic derivative properties of the pure fluids based on a single set of group parameters. Furthermore, the application of the perturbation expansion to third order for the description of the reference monomeric fluid improves the predictions of the theory for the fluid-phase behavior of pure components in the near-critical region. The predictive capabilities of the approach stem from its formulation within a group-contribution formalism: predictions of the fluid-phase behavior and thermodynamic derivative properties of

Bipolar Radiofrequency Ablation Using Dual Internally Cooled Wet Electrodes: Experimental Study in Ex Vivo Bovine Liver

Energy Technology Data Exchange (ETDEWEB)

Lee, Young Joon; Byun, Jae Young [Dept. of Radiology, Seoul St. Mary' s Hospital, The Catholic University of Korea, College of Medicine, Seoul (Korea, Republic of)

2012-11-15

To determine the optimized protocol for bipolar radiofrequency ablation (RFA), using dual internally cooled wet (ICW) electrodes in the ex vivo bovine liver. RFA was applied to the explanted bovine liver, using two 3 cm active tip electrodes with 3.5 cm spacing. A total of 25 ablation zones were created by five groups; group A: 70 W-20 minute (min), group B: 70 W-25 min, group C: 90 W-15 min, group D: 90 W-20 min, and group E: 90 W-25 min. We measured the total energy and size of ablation zones with a color of grey or pink. Statistical analysis was done using Kruskal Wallis test and Mann Whitney U-test. The mean energy, mean volume of ablation zone with grey and pink color of groups A to E were 16.7, 23.9, 16.7, 21.8, 29.2 kcal, 25.7, 34.3, 29.5, 36.2, 45.2 cm{sup 3}, and 60.0, 88.0, 71.5, 87.4, 104.5 cm{sup 3}, respectively. Those were significantly different (p < 0.05). The volume of ablation zone of group E with grey color was larger than groups A, B and C (p < 0.05). Bipolar RFA, using dual ICW electrodes, can produce a large ablation zone with the protocol of 90 W-25 min.

Bipolar Radiofrequency Ablation Using Dual Internally Cooled Wet Electrodes: Experimental Study in Ex Vivo Bovine Liver

International Nuclear Information System (INIS)

Lee, Young Joon; Byun, Jae Young

2012-01-01

To determine the optimized protocol for bipolar radiofrequency ablation (RFA), using dual internally cooled wet (ICW) electrodes in the ex vivo bovine liver. RFA was applied to the explanted bovine liver, using two 3 cm active tip electrodes with 3.5 cm spacing. A total of 25 ablation zones were created by five groups; group A: 70 W-20 minute (min), group B: 70 W-25 min, group C: 90 W-15 min, group D: 90 W-20 min, and group E: 90 W-25 min. We measured the total energy and size of ablation zones with a color of grey or pink. Statistical analysis was done using Kruskal Wallis test and Mann Whitney U-test. The mean energy, mean volume of ablation zone with grey and pink color of groups A to E were 16.7, 23.9, 16.7, 21.8, 29.2 kcal, 25.7, 34.3, 29.5, 36.2, 45.2 cm 3 , and 60.0, 88.0, 71.5, 87.4, 104.5 cm 3 , respectively. Those were significantly different (p < 0.05). The volume of ablation zone of group E with grey color was larger than groups A, B and C (p < 0.05). Bipolar RFA, using dual ICW electrodes, can produce a large ablation zone with the protocol of 90 W-25 min.

Properties of dual codes defined by nondegenerate forms

Directory of Open Access Journals (Sweden)

Steve Szabo

2017-01-01

Full Text Available Dual codes are defined with respect to non-degenerate sesquilinear or bilinear forms over a finite Frobenius ring. These dual codes have the properties one expects from a dual code: they satisfy a double-dual property, they have cardinality complementary to that of the primal code, and they satisfy the MacWilliams identities for the Hamming weight.

Quantification of coronary artery calcium on the basis of dual-energy coronary CT angiography.

Science.gov (United States)

Schwarz, Florian; Nance, John W; Ruzsics, Balazs; Bastarrika, Gorka; Sterzik, Alexander; Schoepf, U Joseph

2012-09-01

To evaluate the feasibility of using virtual noncontrast material-enhanced (VNC) computed tomographic (CT) series derived from dual-energy CT imaging studies for coronary artery calcium quantification. This HIPAA-compliant study was institutional review board approved; all patients provided written informed consent. Thirty-six patients prospectively underwent noncontrast-enhanced CT calcium scoring followed by coronary CT angiography performed in dual-energy mode. By using different reconstruction algorithms, three VNC series were generated and evaluated for noise and efficiency of virtual iodine removal. Two readers independently quantified calcium on VNC images and true noncontrast-enhanced conventional calcium scoring series. A leave-one-out cross validation was used to assess the accuracy of calcium score prediction from VNC series by means of linear regression. CT value histograms of the VNC series closely resembled the profile in the true noncontrast-enhanced series. There was excellent correlation between calcium volumes on the VNC series and true noncontrast-enhanced series on a per-patient (r = 0.94, P VNC series was excellent (r = 0.82). Multiethnic Study of Atherosclerosis rankings that were derived from the predicted calcium scores also showed excellent agreement (intraclass correlation coefficient = 0.909). Coronary artery calcium identification and quantification based on dual-energy coronary CT angiographic studies may obviate the need for dedicated CT calcium scoring studies. © RSNA, 2012

Differentiation of malignant and benign pulmonary nodules with first-pass dual-input perfusion CT

International Nuclear Information System (INIS)

Yuan, Xiaodong; Quan, Changbin; Cao, Jianxia; Ao, Guokun; Tian, Yuan; Li, Hong; Zhang, Jing

2013-01-01

To assess diagnostic performance of dual-input CT perfusion for distinguishing malignant from benign solitary pulmonary nodules (SPNs). Fifty-six consecutive subjects with SPNs underwent contrast-enhanced 320-row multidetector dynamic volume CT. The dual-input maximum slope CT perfusion analysis was employed to calculate the pulmonary flow (PF), bronchial flow (BF), and perfusion index (PI,=PF/(PF+BF)). Differences in perfusion parameters between malignant and benign tumours were assessed with histopathological diagnosis as the gold standard. Diagnostic value of the perfusion parameters was calculated using the receiver-operating characteristic (ROC) curve analysis. Amongst 56 SPNs, statistically significant differences in all three perfusion parameters were revealed between malignant and benign tumours. The PI demonstrated the biggest difference between malignancy and benignancy: 0.30 ± 0.07 vs. 0.51 ± 0.13, P < 0.001. The area under the PI ROC curve was 0.92, the largest of the three perfusion parameters, producing a sensitivity of 0.95, specificity of 0.83, positive likelihood ratio (+LR) of 5.59, and negative likelihood ratio (-LR) of 0.06 in identifying malignancy. The PI derived from the dual-input maximum slope CT perfusion analysis is a valuable biomarker for identifying malignancy in SPNs. PI may be potentially useful for lung cancer treatment planning and forecasting the therapeutic effect of radiotherapy treatment. (orig.)

An Efficient Construction of Self-Dual Codes

OpenAIRE

Lee, Yoonjin; Kim, Jon-Lark

2012-01-01

We complete the building-up construction for self-dual codes by resolving the open cases over $GF(q)$ with $q \\equiv 3 \\pmod 4$, and over $\\Z_{p^m}$ and Galois rings $\\GR(p^m,r)$ with an odd prime $p$ satisfying $p \\equiv 3 \\pmod 4$ with $r$ odd. We also extend the building-up construction for self-dual codes to finite chain rings. Our building-up construction produces many new interesting self-dual codes. In particular, we construct 945 new extremal self-dual ternary $[32,16,9]$ codes, each ...

Dual Kidney Allocation Score: A Novel Algorithm Utilizing Expanded Donor Criteria for the Allocation of Dual Kidneys in Adults.

Science.gov (United States)

Johnson, Adam P; Price, Thea P; Lieby, Benjamin; Doria, Cataldo

2016-09-08

BACKGROUND Dual kidney transplantation (DKT) of expanded-criteria donors is a cost-intensive procedure that aims to increase the pool of available deceased organ donors and has demonstrated equivalent outcomes to expanded-criteria single kidney transplantation (eSKT). The objective of this study was to develop an allocation score based on predicted graft survival from historical dual and single kidney donors. MATERIAL AND METHODS We analyzed United Network for Organ Sharing (UNOS) data for 1547 DKT and 26 381 eSKT performed between January 1994 and September 2013. We utilized multivariable Cox regression to identify variables independently associated with graft survival in dual and single kidney transplantations. We then derived a weighted multivariable product score from calculated hazard ratios to model the benefit of transplantation as dual kidneys. RESULTS Of 36 donor variables known at the time of listing, 13 were significantly associated with graft survival. The derived dual allocation score demonstrated good internal validity with strong correlation to improved survival in dual kidney transplants. Donors with scores less than 2.1 transplanted as dual kidneys had a worsened median survival of 594 days (24%, p-value 0.031) and donors with scores greater than 3.9 had improved median survival of 1107 days (71%, p-value 0.002). There were 17 733 eSKT (67%) and 1051 DKT (67%) with scores in between these values and no differences in survival (p-values 0.676 and 0.185). CONCLUSIONS We have derived a dual kidney allocation score (DKAS) with good internal validity. Future prospective studies will be required to demonstrate external validity, but this score may help to standardize organ allocation for dual kidney transplantation.

Assessment of CO2 Storage Potential in Naturally Fractured Reservoirs With Dual-Porosity Models

Science.gov (United States)

March, Rafael; Doster, Florian; Geiger, Sebastian

2018-03-01

Naturally Fractured Reservoirs (NFR's) have received little attention as potential CO2 storage sites. Two main facts deter from storage projects in fractured reservoirs: (1) CO2 tends to be nonwetting in target formations and capillary forces will keep CO2 in the fractures, which typically have low pore volume; and (2) the high conductivity of the fractures may lead to increased spatial spreading of the CO2 plume. Numerical simulations are a powerful tool to understand the physics behind brine-CO2 flow in NFR's. Dual-porosity models are typically used to simulate multiphase flow in fractured formations. However, existing dual-porosity models are based on crude approximations of the matrix-fracture fluid transfer processes and often fail to capture the dynamics of fluid exchange accurately. Therefore, more accurate transfer functions are needed in order to evaluate the CO2 transfer to the matrix. This work presents an assessment of CO2 storage potential in NFR's using dual-porosity models. We investigate the impact of a system of fractures on storage in a saline aquifer, by analyzing the time scales of brine drainage by CO2 in the matrix blocks and the maximum CO2 that can be stored in the rock matrix. A new model to estimate drainage time scales is developed and used in a transfer function for dual-porosity simulations. We then analyze how injection rates should be limited in order to avoid early spill of CO2 (lost control of the plume) on a conceptual anticline model. Numerical simulations on the anticline show that naturally fractured reservoirs may be used to store CO2.

The high-energy dual-beam facility

International Nuclear Information System (INIS)

Kaletta, D.

1984-07-01

This proposal presents a new experimental facility at the Kernforschungszentrum Karlsruhe (KfK) to study the effects of irradiation on the first wall and blanket materials of a fusion reactor. A special effort is made to demonstrate the advantages of the Dual Beam Technique (DBT) as a future research tool for materials development within the European Fusion Technology Programme. The Dual-Beam-Technique allows the production both of helium and of damage in thick metal and ceramic specimens by simultaneous irradiation with high energy alpha particles and protons produced by the two KfK cyclotrons. The proposal describes the Dual Beam Technique the planned experimental activities and the design features of the Dual Beam Facility presently under construction. (orig.) [de

Sparsity and spectral properties of dual frames

DEFF Research Database (Denmark)

Krahmer, Felix; Kutyniok, Gitta; Lemvig, Jakob

2013-01-01

We study sparsity and spectral properties of dual frames of a given finite frame. We show that any finite frame has a dual with no more than $n^2$ non-vanishing entries, where $n$ denotes the ambient dimension, and that for most frames no sparser dual is possible. Moreover, we derive an expressio...

Linear chemically sensitive electron tomography using DualEELS and dictionary-based compressed sensing

Energy Technology Data Exchange (ETDEWEB)

AlAfeef, Ala, E-mail: a.al-afeef.1@research.gla.ac.uk [SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom); School of Computing Science, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Bobynko, Joanna [SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Cockshott, W. Paul. [School of Computing Science, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Craven, Alan J. [SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Zuazo, Ian; Barges, Patrick [ArcelorMittal Maizières Research, Maizières-lès-Metz 57283 (France); MacLaren, Ian, E-mail: ian.maclaren@glasgow.ac.uk [SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom)

2016-11-15

We have investigated the use of DualEELS in elementally sensitive tilt series tomography in the scanning transmission electron microscope. A procedure is implemented using deconvolution to remove the effects of multiple scattering, followed by normalisation by the zero loss peak intensity. This is performed to produce a signal that is linearly dependent on the projected density of the element in each pixel. This method is compared with one that does not include deconvolution (although normalisation by the zero loss peak intensity is still performed). Additionally, we compare the 3D reconstruction using a new compressed sensing algorithm, DLET, with the well-established SIRT algorithm. VC precipitates, which are extracted from a steel on a carbon replica, are used in this study. It is found that the use of this linear signal results in a very even density throughout the precipitates. However, when deconvolution is omitted, a slight density reduction is observed in the cores of the precipitates (a so-called cupping artefact). Additionally, it is clearly demonstrated that the 3D morphology is much better reproduced using the DLET algorithm, with very little elongation in the missing wedge direction. It is therefore concluded that reliable elementally sensitive tilt tomography using EELS requires the appropriate use of DualEELS together with a suitable reconstruction algorithm, such as the compressed sensing based reconstruction algorithm used here, to make the best use of the limited data volume and signal to noise inherent in core-loss EELS. - Highlights: • DualEELS is essential for chemically sensitive electron tomography using EELS. • A new compressed sensing based algorithm (DLET) gives high fidelity reconstruction. • This combination of DualEELS and DLET will give reliable results from few projections.

Dual Treatments as Starting Point for Integrative Perceptions in Teaching Mathematics

Science.gov (United States)

Kërënxhi, Svjetllana; Gjoci, Pranvera

2015-01-01

In this paper, we recommend mathematical teaching through dual treatments. The dual treatments notion, classified in dual interpretations, dual analyses, dual solutions, and dual formulations, is explained through concrete examples taken from mathematical textbooks of elementary education. Dual treatments provide opportunities for creating…

Split-dose administration of a dual-action, low-volume bowel cleanser for colonoscopy: the SEE CLEAR I study.

Science.gov (United States)

Rex, Douglas K; Katz, Philip O; Bertiger, Gerald; Vanner, Stephen; Hookey, Lawrence C; Alderfer, Vivian; Joseph, Raymond E

2013-07-01

New bowel cleansers for colonoscopy that lead to improved efficacy, safety, and tolerability are needed. This study evaluated a nonphosphate, dual-action, low-volume, orange-flavored preparation containing sodium picosulfate and magnesium citrate (P/MC). Multicenter, assessor-blinded, randomized, noninferiority study. University hospitals, academic medical centers, and private clinics across the United States. Adults preparing for colonoscopy. P/MC versus 2 L of polyethylene glycol solution (2L PEG-3350) and two 5-mg bisacodyl tablets. This phase 3 study investigated the efficacy, safety, and tolerability of split-dose administration of P/MC versus day-before dosing of 2L PEG-3350 and two 5-mg bisacodyl tablets (SEE CLEAR I study). Efficacy was evaluated by using the Aronchick and Ottawa scales; noninferiority and superiority analyses were performed. Safety was assessed by monitoring adverse events (AEs). Tolerability was measured via a patient questionnaire. The intent-to-treat population consisted of 601 patients who self-administered P/MC (n = 304) or 2L PEG-3350 and bisacodyl tablets (n = 297). P/MC was superior to 2L PEG-3350 and bisacodyl tablets in overall colon cleansing (84.2% vs 74.4%; 1-sided 97.5% confidence interval [CI], 3.4) (Aronchick scores of excellent or good) and in cleansing of the ascending (89.5% vs 78.8%; 1-sided 97.5% CI, 4.9), mid (transverse and descending) (92.4% vs 85.9%; 1-sided 97.5% CI, 1.6), and rectosigmoid (92.4% vs 87.2%; 1-sided 97.5% CI, 0.4) segments of the colon (Ottawa scores of excellent, good, or fair). Commonly reported AEs related to the bowel preparations were nausea, vomiting, headache, and chills. Patient-reported tolerability, including ease of consumption and taste, was significantly higher for P/MC than 2L PEG-3350 and bisacodyl tablets (P PEG-3350 and bisacodyl tablets. Copyright © 2013 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

Prediction of infarction development after endovascular stroke therapy with dual-energy computed tomography.

Science.gov (United States)

Djurdjevic, Tanja; Rehwald, Rafael; Knoflach, Michael; Matosevic, Benjamin; Kiechl, Stefan; Gizewski, Elke Ruth; Glodny, Bernhard; Grams, Astrid Ellen

2017-03-01

After intraarterial recanalisation (IAR), the haemorrhage and the blood-brain barrier (BBB) disruption can be distinguished using dual-energy computed tomography (DECT). The aim of the present study was to investigate whether future infarction development can be predicted from DECT. DECT scans of 20 patients showing 45 BBB disrupted areas after IAR were assessed and compared with follow-up examinations. Receiver operator characteristic (ROC) analyses using densities from the iodine map (IM) and virtual non-contrast (VNC) were performed. Future infarction areas are denser than future non-infarction areas on IM series (23.44 ± 24.86 vs. 5.77 ± 2.77; p VNC series (29.71 ± 3.33 vs. 35.33 ± 3.50; p 17.13 HU; p VNC series allowed prediction of infarction volume. Future infarction development after IAR can be reliably predicted with the IM series. The prediction of haemorrhages and of infarction size is less reliable. • The IM series (DECT) can predict future infarction development after IAR. • Later haemorrhages can be predicted using the IM and the BW series. • The volume of definable hypodense areas in VNC correlates with infarction volume.

Dual Coding, Reasoning and Fallacies.

Science.gov (United States)

Hample, Dale

1982-01-01

Develops the theory that a fallacy is not a comparison of a rhetorical text to a set of definitions but a comparison of one person's cognition with another's. Reviews Paivio's dual coding theory, relates nonverbal coding to reasoning processes, and generates a limited fallacy theory based on dual coding theory. (PD)

Physiological control of dual rotary pumps as a biventricular assist device using a master/slave approach.

Science.gov (United States)

Stevens, Michael C; Wilson, Stephen; Bradley, Andrew; Fraser, John; Timms, Daniel

2014-09-01

Dual rotary left ventricular assist devices (LVADs) can provide biventricular mechanical support during heart failure. Coordination of left and right pump speeds is critical not only to avoid ventricular suction and to match cardiac output with demand, but also to ensure balanced systemic and pulmonary circulatory volumes. Physiological control systems for dual LVADs must meet these objectives across a variety of clinical scenarios by automatically adjusting left and right pump speeds to avoid catastrophic physiological consequences. In this study we evaluate a novel master/slave physiological control system for dual LVADs. The master controller is a Starling-like controller, which sets flow rate as a function of end-diastolic ventricular pressure (EDP). The slave controller then maintains a linear relationship between right and left EDPs. Both left/right and right/left master/slave combinations were evaluated by subjecting them to four clinical scenarios (rest, postural change, Valsalva maneuver, and exercise) simulated in a mock circulation loop. The controller's performance was compared to constant-rotational-speed control and two other dual LVAD control systems: dual constant inlet pressure and dual Frank-Starling control. The results showed that the master/slave physiological control system produced fewer suction events than constant-speed control (6 vs. 62 over a 7-min period). Left/right master/slave control had lower risk of pulmonary congestion than the other control systems, as indicated by lower maximum EDPs (15.1 vs. 25.2-28.4 mm Hg). During exercise, master/slave control increased total flow from 5.2 to 10.1 L/min, primarily due to an increase of left and right pump speed. Use of the left pump as the master resulted in fewer suction events and lower EDPs than when the right pump was master. Based on these results, master/slave control using the left pump as the master automatically adjusts pump speed to avoid suction and increases pump flow

Dual-source dual-energy CT for the differentiation of urinary stone composition: preliminary study

International Nuclear Information System (INIS)

Yang Qifang; Zhang Wanshi; Meng Limin; Shi Huiping; Wang Dong; Bi Yongmin; Li Xiangsheng; Fang Hong; Guo Heqing; Yan Jingmin

2011-01-01

Objective: To evaluate dual-source dual-energy CT (DSCT) for the differentiation of' urinary stone composition in vitro. Methods: Ninety-seven urinary stones were obtained by endoscopic lithotripsy and scanned using dual-source dual-energy CT. The stones were divided into six groups according to infrared spectroscopy stone analysis: uric acid (UA) stones (n=10), cystine stones (n=5), struvite stones (n=6), calcium oxalate (CaOx) stones (n=22), mixed UA stones (n=7) and mixed calcium stones (n=47). Hounsfield units (HU) of each stone were recorded for the 80 kV and the 140 kV datasets by hand-drawing method. HU difference, HU ratio and dual energy index (DEI) were calculated and compared among the stone groups with one-way ANOVA. Using dual energy software to determine the composition of all stones, results were compared to infrared spectroscopy analysis. Results: There were statistical differences in HU difference [(-17±13), (229±34), (309±45), (512±97), (201±64) and (530±71) HU respectively], in HU ratio (0.96±0.03, 1.34±0.04, 1.41±0.03, 1.47±0.03, 1.30±0.07, and 1.49±0.03 respectively), and DEI (-0.006±0.004, 0.064±0.007, 0.080± 0.007, 0.108±0.011, 0.055±0.014 and 0.112±0.008 respectively) among different stone groups (F= 124.894, 407.028, 322.864 respectively, P<0.01). There were statistical differences in HU difference, HU ratio and DEI between UA stones and the other groups (P<0.01). There were statistical differences in HU difference, HU ratio and DEI between CaOx or mixed calcium stones and the other four groups (P< 0.01). There was statistical difference in HU ratio between cystine and struvite stones (P<0.01). There were statistical differences in HU difference, HU ratio and DEI between struvite and mixed UA stones (P< 0.05). Dual energy software correctly characterized 10 UA stones, 4 cystine stones, 22 CaOx stones and 6 mixed UA stones. Two struvite stones were considered to contain cystine. One cystine stone, 1 mixed UA stone, 4

Dual method use among long-acting reversible contraceptive users.

Science.gov (United States)

Bernard, Caitlin; Zhao, Qiuhong; Peipert, Jeffrey F

2018-03-27

To compare rates of dual method use (concurrent use of condoms and an effective method of contraception) in long-acting reversible contraceptive (LARC) and non-LARC hormonal contraceptive users, and to determine factors associated with dual method use. We conducted a secondary analysis of the Contraceptive CHOICE Project, an observational, prospective cohort study of 9256 women in St. Louis, MO, USA. Our sample included 6744 women who initiated a contraceptive method within 3 months of enrollment, continued use at 6 months post-enrollment, and responded regarding dual method use. Our primary outcome was the rate of dual method use at 6 months post-enrollment. Dual method use was reported by 32% of LARC and 45% of non-LARC hormonal contraceptive users (p dual method use (RR adj 0.76, 95% CI 0.70-0.83). Factors associated with dual method use in our multivariable analysis were age dual method use, baseline diagnosis of sexually transmitted infection (STI), greater partner willingness to use a condom, and higher condom self-efficacy score. LARC users are less likely to report dual method use compared to non-LARC hormonal contraceptive users, but other factors also impact dual method use. Further studies should be performed to determine whether this lower dual method use increases the risk of STI. Clinicaltrials.gov Identifier NCT01986439.

The dual of the Carroll-Field-Jackiw model

International Nuclear Information System (INIS)

Guimaraes, M.S.; Grigorio, L.; Wotzasek, C.

2006-01-01

In this work we apply different duality techniques, both the dual projection, based on the soldering formalism and the master action, in order to obtain and study the dual description of the Carroll- Field-Jackiw model [1], a theory with a Chern-Simons-like explicitly Lorentz and CPT violating term, including the interaction with external charges. This Maxwell-Chern-Simons-like model may be rewritten in terms of the interacting modes of a massless scalar model and a topologically massive model [2], that are mapped, through duality, into interacting massless Maxwell and massive self-dual modes [3]. It is also shown that these dual modes might be represented into an unified rank-two self-dual model that represents the direct dual of the vector Maxwell-Chern-Simons-like model

Determination of local carbon content in austenite during intercritical annealing of dual phase steels by PEELS analysis

International Nuclear Information System (INIS)

Garcia-Junceda, A.; Caballero, F.G.; Capdevila, C.; Garcia de Andres, C.

2007-01-01

Parallel electron energy loss spectroscopy has allowed to analyse and quantify local variations in the carbon concentration of austenite islands transformed during the intercritical annealing treatment of commercial dual-phase steels. These changes in the carbon content of different austenite regions are responsible for the different volume fractions of tempered martensite, martensite and retained austenite obtained after intercritical annealing and overaging treatment. This technique reveals how carbon distribution in austenite evolves as the transformation process advances

Mathematical model for the preliminary analysis of dual-mode space nuclear fission solid core power and propulsion systems, NUROC3A. AMS report No. 1239a

Energy Technology Data Exchange (ETDEWEB)

Grey, J.; Chow, S.

1976-06-30

The three-volume report describes a dual-mode nuclear space power and propulsion system concept that employs an advanced solid-core nuclear fission reactor coupled via heat pipes to one of several electric power conversion systems. Such a concept could be particularly useful for missions which require both relatively high acceleration (e.g., for planetocentric maneuvers) and high performance at low acceleration (e.g., on heliocentric trajectories or for trajectory shaping). The first volume develops the mathematical model of the system.

Evaluation of Myc Gene Amplification in Prostate Cancer Using a Dual Color Chromogenic in-Situ Hybridization (Dual CISH Assay

Directory of Open Access Journals (Sweden)

Daniel Lerda

2013-04-01

Full Text Available Objetive: The overall purpose of the study was to demonstrate applicability of the Dako dual-color chromogenic in situ hybridization (CISH assay (DAKO Denmark, Glostrup with respect to fluorescence in situ hybridization (FISH probes MYC-C. Methods: MYC gene amplification by FISH and Dako dual-color CISH Results: The study showed that the dual-color CISH assay can convert Texas red and fluorescein isothiocyanate (FITC signals into chromogenic signals. The dual –color CISH assay was performed on 40 cases of prostate cancer. Amplification was identified in 12 of 40 (30% tumors. No amplification was seen in 28 of 40 (70% tumors. FISH data were available in total of 40 tumors. All tumors showed concordant results between dual-color CISH and FISH for classifying a tumor as MYC amplified or not amplified. Conclusions: We conclude that dual-color Dako CISH assay is an accurate method for determining MYC gene amplification with added advantages that make it a more practically useful method. [J Interdiscipl Histopathol 2013; 1(2.000: 81-84

Dual-Energy CT of Rectal Cancer Specimens

DEFF Research Database (Denmark)

Al-Najami, Issam; Beets-Tan, Regina G H; Madsen, Gunvor

2016-01-01

is represented by a certain effective Z value, which allows for information on its composition. OBJECTIVE: We wanted to standardize a method for dual-energy scanning of rectal specimens to evaluate the sensitivity and specificity of benign versus malignant lymph node differentiation. Histopathological evaluation...... cancer. MAIN OUTCOME MEASURES: We measured accuracy of differentiating benign from malignant lymph nodes by investigating the following: 1) gadolinium, iodine, and water concentrations in lymph nodes; 2) dual-energy ratio; 3) dual-energy index; and 4) effective Z value. RESULTS: Optimal discriminations...... between benign and malignant lymph nodes were obtained using the following cutoff values: 1) effective Z at 7.58 (sensitivity, 100%; specificity, 90%; and accuracy, 93%), 2) dual-energy ratio at 1.0 × 10 (sensitivity, 96%; specificity, 87%; and accuracy, 90%), 3) dual-energy index at 0.03 (sensitivity, 97...

Dual mechanical behaviour of hydrogen in stressed silicon nitride thin films

International Nuclear Information System (INIS)

Volpi, F.; Braccini, M.; Pasturel, A.; Devos, A.; Raymond, G.; Morin, P.

2014-01-01

In the present article, we report a study on the mechanical behaviour displayed by hydrogen atoms and pores in silicon nitride (SiN) films. A simple three-phase model is proposed to relate the physical properties (stiffness, film stress, mass density, etc.) of hydrogenated nanoporous SiN thin films to the volume fractions of hydrogen and pores. This model is then applied to experimental data extracted from films deposited by plasma enhanced chemical vapour deposition, where hydrogen content, stress, and mass densities range widely from 11% to 30%, −2.8 to 1.5 GPa, and 2.0 to 2.8 g/cm 3 , respectively. Starting from the conventional plotting of film's Young's modulus against film porosity, we first propose to correct the conventional calculation of porosity volume fraction with the hydrogen content, thus taking into account both hydrogen mass and concentration. The weight of this hydrogen-correction is found to evolve linearly with hydrogen concentration in tensile films (in accordance with a simple “mass correction” of the film density calculation), but a clear discontinuity is observed toward compressive stresses. Then, the effective volume occupied by hydrogen atoms is calculated taking account of the bond type (N-H or Si-H bonds), thus allowing a precise extraction of the hydrogen volume fraction. These calculations applied to tensile films show that both volume fractions of hydrogen and porosity are similar in magnitude and randomly distributed against Young's modulus. However, the expected linear dependence of the Young's modulus is clearly observed when both volume fractions are added. Finally, we show that the stiffer behaviour of compressive films cannot be only explained on the basis of this (hydrogen + porosity) volume fraction. Indeed this stiffness difference relies on a dual mechanical behaviour displayed by hydrogen atoms against the film stress state: while they participate to the stiffness in compressive films, hydrogen atoms mainly

Dual use research: investigation across multiple science disciplines.

Science.gov (United States)

Oltmann, Shannon

2015-04-01

Most recent studies of dual use research have focused on the life sciences, although some researchers have suggested that dual use research occurs across many disciplines. This research is an initial investigation into the prevalence of dual use research in other scientific disciplines by surveying senior editors of scientific journals, drawn from Journal Citation Reports. The survey was emailed to 7,500 journal editors with a response rate of 10.1 %. Approximately 4.8 % of life science editors reported they had to consider whether to publish dual use research and 38.9 % said they decided to not publish the research in question. In disciplines other than the life sciences, 7.2 % of editors from other science disciplines reported that they had to consider whether to publish dual use research, and 48.4 % declined to publish it. The survey investigated relationships between dual use and the journal's source of funding and place of publication, but no relationships were found. Further research is needed to better understand the occurrence of dual use research in other science disciplines.

Design and neutronic investigation of the Nano fluids application to VVER-1000 nuclear reactor with dual cooled annular fuel

International Nuclear Information System (INIS)

Ansarifar, G.R.; Ebrahimian, M.

2016-01-01

Highlights: • The change in neutronic parameters to the use of nanofluid as coolant is presented. • Nanoparticle deposition on fuel clad is investigated. • Radial and axial local power peaking factors are presented. • ZrO 2 and Al 2 O 3 have the lowest rate of K eff drop off. - Abstract: Nowadays, many efforts have been made to improve the efficiency of nuclear power plants. One of which is use of the dual cooled annular fuel which is an internally and externally cooled annular fuel with many advantages in heat transfer characteristics. Another is the use of nanoparticle/water (nanofluid) as coolant. In this paper, by combining these two methods, the change in neutronic parameters of the VVER-1000 nuclear reactor core with dual cooled annular fuel attributable to the use of nanoparticle/water (nanofluid) as coolant is presented. Optimization of type and volume fraction of nanoparticles in water that affect the safety enhancement of core primary parameters is intended in this study. Reactivity change, radial and axial local power peaking factors (LPPF), and the consequence of nanoparticle deposition on fuel clad are investigated. As a result of changing the effective multiplication factor and PPF calculations for six types of nanoparticles which have been studied extensively for their heat transfer properties including Alumina, Aluminum, Copper oxide, Copper, Titania, and Zirconia with different volume fractions, it can be concluded that at low concentration (0.03 volume fraction), Zirconia and Alumina are the optimum nanoparticles for normal operation. The maximum radial and axial PPF are found to be invariant to the type of nanofluid at low volume fractions. With an increase in nanoparticle deposition thickness on the outer and inner clad, a flux and K eff depression occurred and ZrO 2 and Al 2 O 3 have the lowest rate of drop off.

Some dual relations in twistor theory

International Nuclear Information System (INIS)

Tarski, J.

1983-08-01

The option of employing twistors or dual twistors in integral representations, etc., is considered. In particular, dual-space analyses are presented which relate to the problem of background electromagnetic fields, and to the inverse transformation. (author)

Multimaterial Decomposition Algorithm for the Quantification of Liver Fat Content by Using Fast-Kilovolt-Peak Switching Dual-Energy CT: Experimental Validation.

Science.gov (United States)

Hyodo, Tomoko; Hori, Masatoshi; Lamb, Peter; Sasaki, Kosuke; Wakayama, Tetsuya; Chiba, Yasutaka; Mochizuki, Teruhito; Murakami, Takamichi

2017-02-01

Purpose To assess the ability of fast-kilovolt-peak switching dual-energy computed tomography (CT) by using the multimaterial decomposition (MMD) algorithm to quantify liver fat. Materials and Methods Fifteen syringes that contained various proportions of swine liver obtained from an abattoir, lard in food products, and iron (saccharated ferric oxide) were prepared. Approval of this study by the animal care and use committee was not required. Solid cylindrical phantoms that consisted of a polyurethane epoxy resin 20 and 30 cm in diameter that held the syringes were scanned with dual- and single-energy 64-section multidetector CT. CT attenuation on single-energy CT images (in Hounsfield units) and MMD-derived fat volume fraction (FVF; dual-energy CT FVF) were obtained for each syringe, as were magnetic resonance (MR) spectroscopy measurements by using a 1.5-T imager (fat fraction [FF] of MR spectroscopy). Reference values of FVF (FVF ref ) were determined by using the Soxhlet method. Iron concentrations were determined by inductively coupled plasma optical emission spectroscopy and divided into three ranges (0 mg per 100 g, 48.1-55.9 mg per 100 g, and 92.6-103.0 mg per 100 g). Statistical analysis included Spearman rank correlation and analysis of covariance. Results Both dual-energy CT FVF (ρ = 0.97; P iron. Phantom size had a significant effect on dual-energy CT FVF after controlling for FVF ref (P iron concentrations, the linear coefficients of dual-energy CT FVF decreased and those of MR spectroscopy FF increased (P iron, dual-energy CT FVF led to underestimateion of FVF ref to a lesser degree than FF of MR spectroscopy led to overestimation of FVF ref . © RSNA, 2016 Online supplemental material is available for this article.

CO and CO2 dual-gas detection based on mid-infrared wideband absorption spectroscopy

Science.gov (United States)

Dong, Ming; Zhong, Guo-qiang; Miao, Shu-zhuo; Zheng, Chuan-tao; Wang, Yi-ding

2018-03-01

A dual-gas sensor system is developed for CO and CO2 detection using a single broadband light source, pyroelectric detectors and time-division multiplexing (TDM) technique. A stepper motor based rotating system and a single-reflection spherical optical mirror are designed and adopted for realizing and enhancing dual-gas detection. Detailed measurements under static detection mode (without rotation) and dynamic mode (with rotation) are performed to study the performance of the sensor system for the two gas samples. The detection period is 7.9 s in one round of detection by scanning the two detectors. Based on an Allan deviation analysis, the 1σ detection limits under static operation are 3.0 parts per million (ppm) in volume and 2.6 ppm for CO and CO2, respectively, and those under dynamic operation are 9.4 ppm and 10.8 ppm for CO and CO2, respectively. The reported sensor has potential applications in various fields requiring CO and CO2 detection such as in the coal mine.

A New Approach to Estimate Forest Parameters Using Dual-Baseline Pol-InSAR Data

Science.gov (United States)

Bai, L.; Hong, W.; Cao, F.; Zhou, Y.

2009-04-01

In POL-InSAR applications using ESPRIT technique, it is assumed that there exist stable scattering centres in the forest. However, the observations in forest severely suffer from volume and temporal decorrelation. The forest scatters are not stable as assumed. The obtained interferometric information is not accurate as expected. Besides, ESPRIT techniques could not identify the interferometric phases corresponding to the ground and the canopy. It provides multiple estimations for the height between two scattering centers due to phase unwrapping. Therefore, estimation errors are introduced to the forest height results. To suppress the two types of errors, we use the dual-baseline POL-InSAR data to estimate forest height. Dual-baseline coherence optimization is applied to obtain interferometric information of stable scattering centers in the forest. From the interferometric phases for different baselines, estimation errors caused by phase unwrapping is solved. Other estimation errors can be suppressed, too. Experiments are done to the ESAR L band POL-InSAR data. Experimental results show the proposed methods provide more accurate forest height than ESPRIT technique.

Dual resonance models and their currents

International Nuclear Information System (INIS)

Johnson, E.A.

1978-01-01

It is shown how dual resonance models were rederived from the concept of a string tracing out a surface in space-time. Thus, interacting strings reproduce the dual amplitudes. A scheme for tackling the unitarity problem began to develop. As a consistent theory of hadronic processes began to be built, workers at the same time were naturally led to expect that leptons could be included with hadrons in a unified dual theory. Thus, there is a search for dual amplitudes which would describe interactions between hadrons and currents (for example, electrons), as well as interactions involving only hadrons. Such amplitudes, it is believed, will be the correct ones, describing the real world. Such amplitudes will provide valuable information concerning such things as hadronic form factors. The great difficulties in building current-amplitudes with the required properties of proper factorization on a good spectrum, duality, current algebra, and proper asymptotic behavior are described. Dual models at the present time require for consistency, an intercept value of α 0 = 1 and a dimension value of d = 26 (or d = 10). There have been speculations that the unphysical dimension may be made physical by associating the ''extra dimensions'' with certain internal degrees of freedom. However, it is desired that the theory itself, force the dimension d = 4. It is quite possible that the dimension problem and the intercept problem are tied together and that resolving either problem will resolve the other. Order by order, a new dual current is constructed that is manifestly factorizable and which appears to be valid for arbitrary space-time dimension. The fact that this current is not bound at d = 26, leads to interesting speculations on the nature of dual currents

Development of a new dual phase steel with laminated microstructural morphology

Energy Technology Data Exchange (ETDEWEB)

Saeidi, N., E-mail: navidsae@gmail.com [Department of Materials Engineering, Isfahan University of Technology, Isfahan, 4156–83111 (Iran, Islamic Republic of); Karimi, M. [Department of Materials Science and Engineering, Shahrood University of Technology, Shahrood, 3619995161 (Iran, Islamic Republic of); Toroghinejad, M.R. [Department of Materials Engineering, Isfahan University of Technology, Isfahan, 4156–83111 (Iran, Islamic Republic of)

2017-05-01

The development of dual phase steels to meet the current world demands, for the purpose of decreasing the fuel consumption with increasing the strength to weight ratio, requires certain microstructural modifications. In the present research, a new morphology of DP steel, known as Laminated–DP steel, as well as its unique production method has been introduced. The new process developed involved properly selecting low carbon steels, stacking them in a laminated manner and performing a roll bonding process followed by short austenitization treatment. The martensite volume fraction was designed and obtained to be 24%. Scanning electron microscopy (SEM) was employed for microstructural examination. Moreover, deformation and tensile behavior of the newly developed steel were studied and compared with those of some ordinary DP steel (ODP). Room temperature uniaxial tensile tests also revealed mechanical properties comparable with those of the commercial DP600 steel, a kind of structural automotive steel. - Highlights: • A new method for producing dual phase steels was introduced. • Employing a new thermo-mechanical process a laminated microstructure was obtained. • Mechanical properties of the new laminated DP steel were studied. • Tensile properties of the new DP steel were comparable with those of the commercial DP600 steel.

Dual phase evolution

CERN Document Server

Green, David G; Abbass, Hussein A

2014-01-01

This book explains how dual phase evolution operates in all these settings and provides a detailed treatment of the subject. The authors discuss the theoretical foundations for the theory, how it relates to other phase transition phenomena and its advantages in evolutionary computation and complex adaptive systems. The book provides methods and techniques to use this concept for problem solving. Dual phase evolution concerns systems that evolve via repeated phase shifts in the connectivity of their elements. It occurs in vast range of settings, including natural systems (species evolution, landscape ecology, geomorphology), socio-economic systems (social networks) and in artificial systems (annealing, evolutionary computing).

Heteronuclear multidimensional NMR and homology modelling studies of the C-terminal nucleotide-binding domain of the human mitochondrial ABC transporter ABCB6

Energy Technology Data Exchange (ETDEWEB)

Kurashima-Ito, Kaori [RIKEN, Cellular and Molecular Biology Laboratory (Japan); Ikeya, Teppei [National Institute of Advanced Industrial Science and Technology (AIST), (Japan); Senbongi, Hiroshi [Mitochondrial Diseases Group, MRC Dunn Human NutritionUnit (United Kingdom); Tochio, Hidehito [International Graduate School of Arts and Sciences, Supramolecular Biology, Yokohama City University, Molecular Biophysics Laboratory (Japan); Mikawa, Tsutomu [RIKEN, Cellular and Molecular Biology Laboratory (Japan); Shibata, Takehiko [RIKEN, Shibata Distinguished Senior Scientist Laboratory (Japan); Ito, Yutaka [RIKEN, Cellular and Molecular Biology Laboratory (Japan)], E-mail: ito-yutaka@center.tmu.ac.jp

2006-05-15

Human ATP-binding cassette, sub-family B, member 6 (ABCB6) is a mitochondrial ABC transporter, and presumably contributes to iron homeostasis. Aimed at understanding the structural basis for the conformational changes accompanying the substrate-transportation cycle, we have studied the C-terminal nucleotide-binding domain of ABCB6 (ABCB6-C) in both the nucleotide-free and ADP-bound states by heteronuclear multidimensional NMR and homology modelling. A non-linear sampling scheme was utilised for indirectly acquired {sup 13}C and {sup 15}N dimensions of all 3D triple-resonance NMR experiments, in order to overcome the instability and the low solubility of ABCB6-C. The backbone resonances for approximately 25% of non-proline residues, which are mostly distributed around the functionally important loops and in the Helical domain, were not observed for nucleotide-free form of ABCB6-C. From the pH, temperature and magnetic field strength dependencies of the resonance intensities, we concluded that this incompleteness in the assignments is mainly due to the exchange between multiple conformations at an intermediate rate on the NMR timescale. These localised conformational dynamics remained in ADP-bound ABCB6-C except for the loops responsible for adenine base and {alpha}/{beta}-phosphate binding. These results revealed that the localised dynamic cooperativity, which was recently proposed for a prokaryotic ABC MJ1267, also exists in a higher eukaryotic ABC, and is presumably shared by all members of the ABC family. Since the Helical domain is the putative interface to the transmembrane domain, this cooperativity may explain the coupled functions between domains in the substrate-transportation cycle.

A fast dual wavelength laser beam fluid-less optical CT scanner for radiotherapy 3D gel dosimetry I: design and development

Science.gov (United States)

Ramm, Daniel

2018-02-01

Three dimensional dosimetry by optical CT readout of radiosensitive gels or solids has previously been indicated as a solution for measurement of radiotherapy 3D dose distributions. The clinical uptake of these dosimetry methods has been limited, partly due to impracticalities of the optical readout such as the expertise and labour required for refractive index fluid matching. In this work a fast laser beam optical CT scanner is described, featuring fluid-less and dual wavelength operation. A second laser with a different wavelength is used to provide an alternative reference scan to the commonly used pre-irradiation scan. Transmission data for both wavelengths is effectively acquired simultaneously, giving a single scan process. Together with the elimination of refractive index fluid matching issues, scanning practicality is substantially improved. Image quality and quantitative accuracy were assessed for both dual and single wavelength methods. The dual wavelength scan technique gave improvements in uniformity of reconstructed optical attenuation coefficients in the sample 3D volume. This was due to a reduction of artefacts caused by scan to scan changes. Optical attenuation measurement accuracy was similar for both dual and single wavelength modes of operation. These results established the basis for further work on dosimetric performance.

Feasibility of a dual regime gyrotron

International Nuclear Information System (INIS)

Sawant, Ashwini; Jain, Prerit; Kartikeyan, M.V.

2012-01-01

The design concept of a 42/84 GHz, 500 kW, CW, dual-regime gyrotron for ECRH of plasma in an experimental Tokamak will be presented in this paper. Operation at 42 GHz is fundamental where as that in 84 GHz will be second harmonic so that a similar guidance system will be retained for dual regime operation. In this paper, the mode competition and mode selection procedures are presented for such a dual regime operation. Cold cavity design and self-consistent calculations will be carried out for power and efficiencies. (author)

On key factors influencing ductile fractures of dual phase (DP) steels

International Nuclear Information System (INIS)

Sun, X.; Choi, K.S.; Soulami, A.; Liu, W.N.; Khaleel, M.A.

2009-01-01

In this paper, we examine the key factors influencing ductile failure of various grades of dual phase (DP) steels using the microstructure-based modeling approach. Various microstructure-based finite element models are generated based on the actual microstructures of DP steels with different martensite volume fractions. These models are, then, used to investigate the influence of ductility of the constituent ferrite phase and also the influence of voids introduced in the ferrite phase on the overall ductility of DP steels. It is found that with volume fraction of martensite in the microstructure less than 15%, the overall ductility of the DP steels strongly depends on the ductility of the ferrite matrix, hence pre-existing micro-voids in the microstructure significantly reduce the overall ductility of the steel. When the volume fraction of martensite is above 15%, the pre-existing voids in the ferrite matrix does not significantly reduce the overall ductility of the DP steels, and the overall ductility is more influenced by the mechanical property disparity between the two phases. The applicability of the phase inhomogeneity driven ductile failure of DP steels is then discussed based on the obtained computational results for various grades of DP steels, and the experimentally obtained scanning electron microscopy (SEM) pictures of the corresponding grades of DP steels near fracture surface are used as evidence for result validations.

Multimaterial Decomposition Algorithm for the Quantification of Liver Fat Content by Using Fast-Kilovolt-Peak Switching Dual-Energy CT: Clinical Evaluation.

Science.gov (United States)

Hyodo, Tomoko; Yada, Norihisa; Hori, Masatoshi; Maenishi, Osamu; Lamb, Peter; Sasaki, Kosuke; Onoda, Minori; Kudo, Masatoshi; Mochizuki, Teruhito; Murakami, Takamichi

2017-04-01

Purpose To assess the clinical accuracy and reproducibility of liver fat quantification with the multimaterial decomposition (MMD) algorithm, comparing the performance of MMD with that of magnetic resonance (MR) spectroscopy by using liver biopsy as the reference standard. Materials and Methods This prospective study was approved by the institutional ethics committee, and patients provided written informed consent. Thirty-three patients suspected of having hepatic steatosis underwent non-contrast material-enhanced and triple-phase dynamic contrast-enhanced dual-energy computed tomography (CT) (80 and 140 kVp) and single-voxel proton MR spectroscopy within 30 days before liver biopsy. Percentage fat volume fraction (FVF) images were generated by using the MMD algorithm on dual-energy CT data to measure hepatic fat content. FVFs determined by using dual-energy CT and percentage fat fractions (FFs) determined by using MR spectroscopy were compared with histologic steatosis grade (0-3, as defined by the nonalcoholic fatty liver disease activity score system) by using Jonckheere-Terpstra trend tests and were compared with each other by using Bland-Altman analysis. Real non-contrast-enhanced FVFs were compared with triple-phase contrast-enhanced FVFs to determine the reproducibility of MMD by using Bland-Altman analyses. Results Both dual-energy CT FVF and MR spectroscopy FF increased with increasing histologic steatosis grade (trend test, P algorithm quantifying hepatic fat in dual-energy CT images is accurate and reproducible across imaging phases. © RSNA, 2017 Online supplemental material is available for this article.

Dual source CT imaging

International Nuclear Information System (INIS)

Seidensticker, Peter R.; Hofmann, Lars K.

2008-01-01

The introduction of Dual Source Computed Tomography (DSCT) in 2005 was an evolutionary leap in the field of CT imaging. Two x-ray sources operated simultaneously enable heart-rate independent temporal resolution and routine spiral dual energy imaging. The precise delivery of contrast media is a critical part of the contrast-enhanced CT procedure. This book provides an introduction to DSCT technology and to the basics of contrast media administration followed by 25 in-depth clinical scan and contrast media injection protocols. All were developed in consensus by selected physicians on the Dual Source CT Expert Panel. Each protocol is complemented by individual considerations, tricks and pitfalls, and by clinical examples from several of the world's best radiologists and cardiologists. This extensive CME-accredited manual is intended to help readers to achieve consistently high image quality, optimal patient care, and a solid starting point for the development of their own unique protocols. (orig.)

Symmetries of the dual metrics

International Nuclear Information System (INIS)

Baleanu, D.

1998-01-01

The geometric duality between the metric g μν and a Killing tensor K μν is studied. The conditions were found when the symmetries of the metric g μν and the dual metric K μν are the same. Dual spinning space was constructed without introduction of torsion. The general results are applied to the case of Kerr-Newmann metric

Microresonator soliton dual-comb spectroscopy

Science.gov (United States)

Suh, Myoung-Gyun; Yang, Qi-Fan; Yang, Ki Youl; Yi, Xu; Vahala, Kerry J.

2016-11-01

Measurement of optical and vibrational spectra with high resolution provides a way to identify chemical species in cluttered environments and is of general importance in many fields. Dual-comb spectroscopy has emerged as a powerful approach for acquiring nearly instantaneous Raman and optical spectra with unprecedented resolution. Spectra are generated directly in the electrical domain, without the need for bulky mechanical spectrometers. We demonstrate a miniature soliton-based dual-comb system that can potentially transfer the approach to a chip platform. These devices achieve high-coherence pulsed mode locking. They also feature broad, reproducible spectral envelopes, an essential feature for dual-comb spectroscopy. Our work shows the potential for integrated spectroscopy with high signal-to-noise ratios and fast acquisition rates.

Non-self-dual nonlinear gravitons

International Nuclear Information System (INIS)

Yasskin, P.B.; Isenberg, J.A.

1982-01-01

Penrose has given a twistor description of all self-dual complex Riemannian space-times. This construction is modified to characterize all complex Riemannian space-times and all complex teleparallel space-times. This construction may be useful in finding non-self-dual solutions to the gravitational field equations (Einstein's or otherwise) without or with sources. It may also lead to a nonperturbative method for computing path integrals. Whereas Penrose shows that a self-dual space-time may be specified by a deformation of projective twistor space (the set of α planes in complex Minkowski space), it is found that a Riemannian or teleparallel space-time may be described by a deformation of projective ambitwistor space (the set of null geodesics in complex Minkowski space). (author)

Duration of dual antiplatelet therapy in acute coronary syndrome.

Science.gov (United States)

Wilson, Simon John; Newby, David E; Dawson, Dana; Irving, John; Berry, Colin

2017-04-01

Despite a large volume of evidence supporting the use of dual antiplatelet therapy in patients with acute coronary syndrome, there remains major uncertainty regarding the optimal duration of therapy. Clinical trials have varied markedly in the duration of therapy, both across and within trials. Recent systematic reviews and meta-analyses suggest that shorter durations of dual antiplatelet therapy are superior because the avoidance of atherothrombotic events is counterbalanced by the greater risks of excess major bleeding with apparent increases in all-cause mortality with longer durations. These findings did not show significant heterogeneity according to whether patients had stable or unstable coronary heart disease. Moreover, the potential hazards and benefits may differ when applied to the general broad population of patients encountered in everyday clinical practice who have markedly higher bleeding and atherothrombotic event rates. Clinicians lack definitive information regarding the duration of therapy in patients with acute coronary syndrome and risk scores do not appear to be sufficiently robust to address these concerns. We believe that there is a pressing need to undertake a broad inclusive safety trial of shorter durations of therapy in real world populations of patients with acute coronary syndrome. The clinical evidence would further inform future research into strategies for personalised medicine. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Wide frequency independently controlled dual-band inkjet-printed antenna

KAUST Repository

AbuTarboush, Hattan F.

2014-01-08

A low-cost inkjet-printed multiband monopole antenna is presented. The unique advantage of the proposed antenna is the freedom to adjust and set the dual-band of the antenna independently over a wide range (148.83%). To demonstrate the independent control feature, the 2.4 and 3.4 GHz bands for the wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) applications are selected as an example. The measured impedance bandwidths for the 2.4 and 3.4 GHz are 15.2 and 23.7%, respectively. These dual-bands have the ability to be controlled independently between 1.1 and 7.5 GHz without affecting the other band. In addition, the proposed antenna can be assigned for different mobile and wireless applications such as GPS, PCS, GSM 1800, 1900, UMTS, and up to 5-GHz WLAN and WiMAX applications. The mechanism of independent control of each radiator through dimensional variation is discussed in detail. The antenna has a compact size of 10 × 37.3 × 0.44 mm3, leaving enough space for the driving electronics on the paper substrate. The measured results from the prototype are in good agreement with the simulated results. Owing to inkjet printing on an ordinary paper, the design is extremely light weight and highly suitable for low cost and large volume manufacturing. © The Institution of Engineering and Technology 2013.

Adaptive sampling dual terahertz comb spectroscopy using dual free-running femtosecond lasers.

Science.gov (United States)

Yasui, Takeshi; Ichikawa, Ryuji; Hsieh, Yi-Da; Hayashi, Kenta; Cahyadi, Harsono; Hindle, Francis; Sakaguchi, Yoshiyuki; Iwata, Tetsuo; Mizutani, Yasuhiro; Yamamoto, Hirotsugu; Minoshima, Kaoru; Inaba, Hajime

2015-06-02

Terahertz (THz) dual comb spectroscopy (DCS) is a promising method for high-accuracy, high-resolution, broadband THz spectroscopy because the mode-resolved THz comb spectrum includes both broadband THz radiation and narrow-line CW-THz radiation characteristics. In addition, all frequency modes of a THz comb can be phase-locked to a microwave frequency standard, providing excellent traceability. However, the need for stabilization of dual femtosecond lasers has often hindered its wide use. To overcome this limitation, here we have demonstrated adaptive-sampling THz-DCS, allowing the use of free-running femtosecond lasers. To correct the fluctuation of the time and frequency scales caused by the laser timing jitter, an adaptive sampling clock is generated by dual THz-comb-referenced spectrum analysers and is used for a timing clock signal in a data acquisition board. The results not only indicated the successful implementation of THz-DCS with free-running lasers but also showed that this configuration outperforms standard THz-DCS with stabilized lasers due to the slight jitter remained in the stabilized lasers.

Simulation of storage performance on hydropneumatic driveline in dual hybrid hydraulic passenger car

Directory of Open Access Journals (Sweden)

Wasbari Faizil

2017-01-01

Full Text Available The charging process is one of the critical processes in the hydro-pneumatic driveline storage system. It converts the kinetic energy of the vehicle braking and coasting to the compression energy. This energy is stored in the storage device called the accumulator. The system is planned to be used on the dual hydro-pneumatic hybrid driveline and applied to a hydraulic hybrid passenger car. The aim of this paper is to find the effect of charging parameters on the storage performance through simulation. Through the storage behaviour, the desirable and optimal sizing of the accumulator can be selected. The paper emphasized on the effect of pressure elevation, pre-charge pressure, effective volume, thermal reaction and required time of the accumulator’s charging process. The circuit of charging process has been designed and simulated by using the hydraulic tool in the Automation Studio software. The simulation results were corroborated through the component specification for data rationality. Through the simulation, it was found that pre-charge pressure had a significant effect on the charging process. It determined the efficiency of the effective volume. The higher the pressure elevation, the higher the effective volume. Nevertheless, the more energy required to compress the nitrogen gas in the bladder. Besides, in term of volume displacement, higher volume displacement reduced charging time and lower the fluid temperature. The simulation had been positively highlighted the critical point in charging process which later on, benefited the sizing process in the component selection specification.

A dual-action, low-volume bowel cleanser administered the day before colonoscopy: results from the SEE CLEAR II study.

Science.gov (United States)

Katz, Philip O; Rex, Douglas K; Epstein, Michael; Grandhi, Nav K; Vanner, Stephen; Hookey, Lawrence C; Alderfer, Vivian; Joseph, Raymond E

2013-03-01

Optimal bowel preparation is vital for the efficacy and safety of colonoscopy. The inconvenience, discomfort, required consumption of large volumes of product, and potential adverse effects associated with some bowel preparations deter patients from colonoscopy and may provide inadequate cleansing. A dual-action, non-phosphate, natural orange-flavored, low-volume preparation containing sodium picosulfate and magnesium citrate (P/MC) is currently being reviewed for bowel cleansing. This was a phase 3, randomized, multicenter, assessor-blinded, prespecified non-inferiority, head-to-head study to investigate the efficacy, safety, and tolerability of day-before administration of P/MC vs. 2L polyethylene glycol solution and two 5-mg bisacodyl tablets (2L PEG-3350 and bisacodyl tablets (HalfLytely and Bisacodyl Tablets Bowel Prep Kit)) in adult patients preparing for colonoscopy (SEE CLEAR II Study). The primary objective of the study was to demonstrate the non-inferiority of P/MC to 2L PEG-3350 and bisacodyl tablets in overall colon cleansing using a modified Aronchick scale. In addition, efficacy in the ascending, mid (transverse and descending), and recto-sigmoid segments of colon was evaluated using a modified Ottawa scale. Patient acceptability and tolerability of the bowel preparations were assessed via a standard questionnaire. Safety was assessed based on the monitoring of adverse events (AEs) and meaningful findings on clinical evaluations including physical examinations, vital sign measurements, and electrocardiograms (ECGs). A total of 603 patients were randomized to receive either P/MC (n = 300) or 2L PEG-3350 and bisacodyl tablets (n = 303). Based on the Aronchick scale, successful overall cleansing was similar in patients receiving P/MC (83.0%) and patients receiving 2L PEG-3350 and bisacodyl tablets (79.7%). P/MC demonstrated non-inferiority to 2L PEG-3350 and bisacodyl tablets in overall cleansing of the colon, as measured by the Aronchick scale

Psychosocial approaches to dual diagnosis.

Science.gov (United States)

Drake, R E; Mueser, K T

2000-01-01

Recent research elucidates many aspects of the problem of co-occurring substance use disorder (SUD) in patients with severe mental illness, which is often termed dual diagnosis. This paper provides a brief overview of current research on the epidemiology, adverse consequences, and phenomenology of dual diagnosis, followed by a more extensive review of current approaches to services, assessment, and treatment. Accumulating evidence shows that comorbid SUD is quite common among individuals with severe mental illness and that these individuals suffer serious adverse consequences of SUD. The research further suggests that traditional, separate services for individuals with dual disorders are ineffective, and that integrated treatment programs, which combine mental health and substance abuse interventions, offer more promise. In addition to a comprehensive integration of services, successful programs include assessment, assertive case management, motivational interventions for patients who do not recognize the need for substance abuse treatment, behavioral interventions for those who are trying to attain or maintain abstinence, family interventions, housing, rehabilitation, and psychopharmacology. Further research is needed on the organization and financing of dual-diagnosis services and on specific components of the integrated treatment model, such as group treatments, family interventions, and housing approaches.

Improving Sustainability through a Dual Audit System

Directory of Open Access Journals (Sweden)

Shun-Ji Jin

2018-01-01

Full Text Available As a consequence of a large-scale accounting fraud, China implemented a dual audit system for listed companies issuing foreign stocks (B shares and H shares from 2001 to 2006, before adopting Chinese-IFRS in 2007. At the end of 2010, the EU proposed that listed corporations over a certain size should be required to implement a joint audit system. However, only a few countries have implemented this system, and thus, data and references are extremely limited. The dual audit system is called the “twin” of the joint audit system. We analyze whether the dual system improves a company’s earnings quality. Earnings quality is studied by means of real earnings management, and the variable of loss aversion. We find that real earnings management of dual audited enterprises is lower than that of single audited (A-share enterprises, and the inclination toward loss aversion of enterprises in the foreign share market has not increased significantly relative to the A-share enterprises after the abolition of the dual audit system. The results indicate that a dual audit system improves earnings quality. We expect that the conclusions of this research will resolve the issues and concerns about the joint audit system.

Detection of Ground Clutter from Weather Radar Using a Dual-Polarization and Dual-Scan Method

Directory of Open Access Journals (Sweden)

Mohammad-Hossein Golbon-Haghighi

2016-06-01

Full Text Available A novel dual-polarization and dual-scan (DPDS classification algorithm is developed for clutter detection in weather radar observations. Two consecutive scans of dual-polarization radar echoes are jointly processed to estimate auto- and cross-correlation functions. Discriminants are then defined and estimated in order to separate clutter from weather based on their physical and statistical properties. An optimal Bayesian classifier is used to make a decision on clutter presence from the estimated discriminant functions. The DPDS algorithm is applied to the data collected with the KOUN polarimetric radar and compared with the existing detection methods. It is shown that the DPDS algorithm yields a higher probability of detection and lower false alarm rate in clutter detection.

A framework to measure myocardial extracellular volume fraction using dual-phase low dose CT images

International Nuclear Information System (INIS)

Liu, Yixun; Summers, Ronald M.; Yao, Jianhua; Liu, Songtao; Sibley, Christopher T.; Bluemke, David A.; Nacif, Marcelo S.

2013-01-01

Purpose: Myocardial extracellular volume fraction (ECVF) is a surrogate imaging biomarker of diffuse myocardial fibrosis, a hallmark of pathologic ventricular remodeling. Low dose cardiac CT is emerging as a promising modality to detect diffuse interstitial myocardial fibrosis due to its fast acquisition and low radiation; however, the insufficient contrast in the low dose CT images poses great challenge to measure ECVF from the image. Methods: To deal with this difficulty, the authors present a complete ECVF measurement framework including a point-guided myocardial modeling, a deformable model-based myocardium segmentation, nonrigid registration of pre- and post-CT, and ECVF calculation. Results: The proposed method was evaluated on 20 patients by two observers. Compared to the manually delineated reference segmentations, the accuracy of our segmentation in terms of true positive volume fraction (TPVF), false positive volume fraction (FPVF), and average surface distance (ASD), were 92.18% ± 3.52%, 0.31% ± 0.10%, 0.69 ± 0.14 mm, respectively. The interobserver variability measured by concordance correlation coefficient regarding TPVF, FPVF, and ASD were 0.95, 0.90, 0.94, respectively, demonstrating excellent agreement. Bland-Altman method showed 95% limits of agreement between ECVF at CT and ECVF at MR. Conclusions: The proposed framework demonstrates its efficiency, accuracy, and noninvasiveness in ECVF measurement and dramatically advances the ECVF at cardiac CT toward its clinical use

A framework to measure myocardial extracellular volume fraction using dual-phase low dose CT images

Energy Technology Data Exchange (ETDEWEB)

Liu, Yixun; Summers, Ronald M.; Yao, Jianhua, E-mail: JYao@cc.nih.gov [Clinical Image Processing Service, Radiology and Imaging Sciences, NIH Clinical Center, Bethesda, Maryland 20892 (United States); Liu, Songtao; Sibley, Christopher T.; Bluemke, David A. [Radiology and Imaging Sciences, NIH Clinical Center, Bethesda, Maryland 20892-1182 and Molecular Biomedical Imaging Laboratory, National Institute of Biomedical Imaging and Bioengineering, NIH Clinical Center, Bethesda, Maryland 20892 (United States); Nacif, Marcelo S. [Radiology and Imaging Sciences, NIH Clinical Center, Bethesda, Maryland 20892-1182 (United States)

2013-10-15

Purpose: Myocardial extracellular volume fraction (ECVF) is a surrogate imaging biomarker of diffuse myocardial fibrosis, a hallmark of pathologic ventricular remodeling. Low dose cardiac CT is emerging as a promising modality to detect diffuse interstitial myocardial fibrosis due to its fast acquisition and low radiation; however, the insufficient contrast in the low dose CT images poses great challenge to measure ECVF from the image. Methods: To deal with this difficulty, the authors present a complete ECVF measurement framework including a point-guided myocardial modeling, a deformable model-based myocardium segmentation, nonrigid registration of pre- and post-CT, and ECVF calculation. Results: The proposed method was evaluated on 20 patients by two observers. Compared to the manually delineated reference segmentations, the accuracy of our segmentation in terms of true positive volume fraction (TPVF), false positive volume fraction (FPVF), and average surface distance (ASD), were 92.18% ± 3.52%, 0.31% ± 0.10%, 0.69 ± 0.14 mm, respectively. The interobserver variability measured by concordance correlation coefficient regarding TPVF, FPVF, and ASD were 0.95, 0.90, 0.94, respectively, demonstrating excellent agreement. Bland-Altman method showed 95% limits of agreement between ECVF at CT and ECVF at MR. Conclusions: The proposed framework demonstrates its efficiency, accuracy, and noninvasiveness in ECVF measurement and dramatically advances the ECVF at cardiac CT toward its clinical use.

Dual wound dc brush motor gearhead

Science.gov (United States)

Henson, Barrie W.

1986-01-01

The design requirements, the design, development tests and problems, the qualification and life test and the findings of the strip examination of a dual wound DC brushed motor gearhead are described. It is the only space qualified dual wound dc brushed motor gearhead in Europe.

US-CT 3D dual imaging by mutual display of the same sections for depicting minor changes in hepatocellular carcinoma

Energy Technology Data Exchange (ETDEWEB)

Fukuda, Hiroyuki, E-mail: fukuhiro1962@hotmail.com [International HIFU Center, Sanmu Medical Center Hospital, Naruto 167, Sanbu-shi, Chiba 289-1326 (Japan); Ito, Ryu; Ohto, Masao; Sakamoto, Akio [International HIFU Center, Sanmu Medical Center Hospital, Naruto 167, Sanbu-shi, Chiba 289-1326 (Japan); Otsuka, Masayuki; Togawa, Akira; Miyazaki, Masaru [Department of General Surgery, Graduate School of Medicine, Chiba University, Inohana 1-8-1, Chuo-ku, Chiba-shi, Chiba 260-0856 (Japan); Yamagata, Hitoshi [Toshiba Medical Systems Corporation, Otawara 324-0036 (Japan)

2012-09-15

The purpose of this study was to evaluate the usefulness of ultrasound-computed tomography (US-CT) 3D dual imaging for the detection of small extranodular growths of hepatocellular carcinoma (HCC). The clinical and pathological profiles of 10 patients with single nodular type HCC with extranodular growth (extranodular growth) who underwent a hepatectomy were evaluated using two-dimensional (2D) ultrasonography (US), three-dimensional (3D) US, 3D computed tomography (CT) and 3D US-CT dual images. Raw 3D data was converted to DICOM (Digital Imaging and Communication in Medicine) data using Echo to CT (Toshiba Medical Systems Corp., Tokyo, Japan), and the 3D DICOM data was directly transferred to the image analysis system (ZioM900, ZIOSOFT Inc., Tokyo, Japan). By inputting the angle number (x, y, z) of the 3D CT volume data into the ZioM900, multiplanar reconstruction (MPR) images of the 3D CT data were displayed in a manner such that they resembled the conventional US images. Eleven extranodular growths were detected pathologically in 10 cases. 2D US was capable of depicting only 2 of the 11 extranodular growths. 3D CT was capable of depicting 4 of the 11 extranodular growths. On the other hand, 3D US was capable of depicting 10 of the 11 extranodular growths, and 3D US-CT dual images, which enable the dual analysis of the CT and US planes, revealed all 11 extranodular growths. In conclusion, US-CT 3D dual imaging may be useful for the detection of small extranodular growths.

US-CT 3D dual imaging by mutual display of the same sections for depicting minor changes in hepatocellular carcinoma

International Nuclear Information System (INIS)

Fukuda, Hiroyuki; Ito, Ryu; Ohto, Masao; Sakamoto, Akio; Otsuka, Masayuki; Togawa, Akira; Miyazaki, Masaru; Yamagata, Hitoshi

2012-01-01

The purpose of this study was to evaluate the usefulness of ultrasound-computed tomography (US-CT) 3D dual imaging for the detection of small extranodular growths of hepatocellular carcinoma (HCC). The clinical and pathological profiles of 10 patients with single nodular type HCC with extranodular growth (extranodular growth) who underwent a hepatectomy were evaluated using two-dimensional (2D) ultrasonography (US), three-dimensional (3D) US, 3D computed tomography (CT) and 3D US-CT dual images. Raw 3D data was converted to DICOM (Digital Imaging and Communication in Medicine) data using Echo to CT (Toshiba Medical Systems Corp., Tokyo, Japan), and the 3D DICOM data was directly transferred to the image analysis system (ZioM900, ZIOSOFT Inc., Tokyo, Japan). By inputting the angle number (x, y, z) of the 3D CT volume data into the ZioM900, multiplanar reconstruction (MPR) images of the 3D CT data were displayed in a manner such that they resembled the conventional US images. Eleven extranodular growths were detected pathologically in 10 cases. 2D US was capable of depicting only 2 of the 11 extranodular growths. 3D CT was capable of depicting 4 of the 11 extranodular growths. On the other hand, 3D US was capable of depicting 10 of the 11 extranodular growths, and 3D US-CT dual images, which enable the dual analysis of the CT and US planes, revealed all 11 extranodular growths. In conclusion, US-CT 3D dual imaging may be useful for the detection of small extranodular growths

30 CFR 62.140 - Dual hearing protection level.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Dual hearing protection level. 62.140 Section... HEALTH REGULATIONS OCCUPATIONAL NOISE EXPOSURE § 62.140 Dual hearing protection level. If during any work shift a miner's noise exposure exceeds the dual hearing protection level, the mine operator must, in...

Dual electromagnetism: helicity, spin, momentum and angular momentum

International Nuclear Information System (INIS)

Bliokh, Konstantin Y; Nori, Franco; Bekshaev, Aleksandr Y

2013-01-01

The dual symmetry between electric and magnetic fields is an important intrinsic property of Maxwell equations in free space. This symmetry underlies the conservation of optical helicity and, as we show here, is closely related to the separation of spin and orbital degrees of freedom of light (the helicity flux coincides with the spin angular momentum). However, in the standard field-theory formulation of electromagnetism, the field Lagrangian is not dual symmetric. This leads to problematic dual-asymmetric forms of the canonical energy–momentum, spin and orbital angular-momentum tensors. Moreover, we show that the components of these tensors conflict with the helicity and energy conservation laws. To resolve this discrepancy between the symmetries of the Lagrangian and Maxwell equations, we put forward a dual-symmetric Lagrangian formulation of classical electromagnetism. This dual electromagnetism preserves the form of Maxwell equations, yields meaningful canonical energy–momentum and angular-momentum tensors, and ensures a self-consistent separation of the spin and orbital degrees of freedom. This provides a rigorous derivation of the results suggested in other recent approaches. We make the Noether analysis of the dual symmetry and all the Poincaré symmetries, examine both local and integral conserved quantities and show that only the dual electromagnetism naturally produces a complete self-consistent set of conservation laws. We also discuss the observability of physical quantities distinguishing the standard and dual theories, as well as relations to quantum weak measurements and various optical experiments. (paper)

The Experience of Dual Career through Slovak Athletes’ Eyes

Directory of Open Access Journals (Sweden)

Geraniosova Kristina

2015-06-01

Full Text Available The purpose of this study was to examine how Slovak athletes experience dual career (the combination of an athletic career with education and/or work. The study strived to gain an understanding of the athletes’ attitudes towards education as well as perceived difficulties and supporting elements in pursuing dual career. Five athletes were interviewed once for approx. 105 min. The interviews and data analysis were based on Intepretative Phenomenological Analysis (IPA and the interviews were focused on their experience in combining an athletic career with education or work. The athletes experienced dual career as manageable as long as they were assisted by at least simple supportive structures and provided flexible arrangements. Peers had played an important role in athletes’ decision-making concerning dual career and in providing social support when facing challenges within dual career. The teachers’ prejudice against the athletes based on their athletic role and the lack of dual career structures appeared to be significant deficiencies in dual career support. Finally, the analysis revealed the negative perception of athletes and sport science students by educational representatives. This perception may be a hurdle to be overcome in future dual career development.

Generalized shift-invariant systems and approximately dual frames

DEFF Research Database (Denmark)

Benavente, Ana; Christensen, Ole; Zakowicz, Maria I.

2017-01-01

Dual pairs of frames yield a procedure for obtaining perfect reconstruction of elements in the underlying Hilbert space in terms of superpositions of the frame elements. However, practical constraints often force us to apply sequences that do not exactly form dual frames. In this article, we...... consider the important case of generalized shift-invariant systems and provide various ways of estimating the deviation from perfect reconstruction that occur when the systems do not form dual frames. The deviation from being dual frames will be measured either in terms of a perturbation condition...

Dual Y-Shaped Monopole Antenna for Dual-Band WLAN/WiMAX Operations

Directory of Open Access Journals (Sweden)

Huiqing Zhai

2014-01-01

Full Text Available A dual-band design of monopole antenna with two coupled Y-shaped strips for WLAN/WiMAX applications is presented. By the introduction of dual Y-shaped strips, two separated impedance bandwidths of 22.4% (3.28~4.10 GHz and 19.2% (4.90~5.94 GHz can be obtained to meet the specifications of the WLAN/WiMAX communication band applications. The proposed antenna is successfully simulated, designed, and measured, demonstrating the matched impedance and good radiation characteristics with an overall dimension of 17.7×26×1 mm3.

Comparison of the effect of radiation exposure from dual-energy CT versus single-energy CT on double-strand breaks at CT pulmonary angiography.

Science.gov (United States)

Tao, Shu Min; Li, Xie; Schoepf, U Joseph; Nance, John W; Jacobs, Brian E; Zhou, Chang Sheng; Gu, Hai Feng; Lu, Meng Jie; Lu, Guang Ming; Zhang, Long Jiang

2018-04-01

To compare the effect of dual-source dual-energy CT versus single-energy CT on DNA double-strand breaks (DSBs) in blood lymphocytes at CT pulmonary angiography (CTPA). Sixty-two patients underwent either dual-energy CTPA (Group 1: n = 21, 80/Sn140 kVp, 89/38 mAs; Group 2: n = 20, 100/Sn140 kVp, 89/76 mAs) or single-energy CTPA (Group 3: n = 21, 120 kVp, 110 mAs). Blood samples were obtained before and 5 min after CTPA. DSBs were assessed with fluorescence microscopy and Kruskal-Walls tests were used to compare DSBs levels among groups. Volume CT dose index (CTDIvol), dose length product (DLP) and organ radiation dose were compared using ANOVA. There were increased excess DSB foci per lymphocyte 5 min after CTPA examinations in three groups (Group 1: P = .001; Group 2: P = .001; Group 3: P = .006). There were no differences among groups regarding excess DSB foci/cell and percentage of excess DSBs (Group 1, 23%; Group 2, 24%; Group 3, 20%; P = .932). CTDIvol, DLP and organ radiation dose in Group 1 were the lowest among the groups (all P dual-source and single-source CTPA, while dual-source dual-energy CT protocols do not increase the estimated radiation dose and also do not result in a higher incidence of DNA DSBs in patients undergoing CTPA. Copyright © 2018 Elsevier B.V. All rights reserved.

Dual-Schemata Model

Science.gov (United States)

Taniguchi, Tadahiro; Sawaragi, Tetsuo

In this paper, a new machine-learning method, called Dual-Schemata model, is presented. Dual-Schemata model is a kind of self-organizational machine learning methods for an autonomous robot interacting with an unknown dynamical environment. This is based on Piaget's Schema model, that is a classical psychological model to explain memory and cognitive development of human beings. Our Dual-Schemata model is developed as a computational model of Piaget's Schema model, especially focusing on sensori-motor developing period. This developmental process is characterized by a couple of two mutually-interacting dynamics; one is a dynamics formed by assimilation and accommodation, and the other dynamics is formed by equilibration and differentiation. By these dynamics schema system enables an agent to act well in a real world. This schema's differentiation process corresponds to a symbol formation process occurring within an autonomous agent when it interacts with an unknown, dynamically changing environment. Experiment results obtained from an autonomous facial robot in which our model is embedded are presented; an autonomous facial robot becomes able to chase a ball moving in various ways without any rewards nor teaching signals from outside. Moreover, emergence of concepts on the target movements within a robot is shown and discussed in terms of fuzzy logics on set-subset inclusive relationships.

WE-FG-206-06: Dual-Input Tracer Kinetic Modeling and Its Analog Implementation for Dynamic Contrast-Enhanced (DCE-) MRI of Malignant Mesothelioma (MPM)

Energy Technology Data Exchange (ETDEWEB)

Lee, S; Rimner, A; Hayes, S; Hunt, M; Deasy, J; Zauderer, M; Rusch, V; Tyagi, N [Memorial Sloan Kettering Cancer Center, New York, NY (United States)

2016-06-15

Purpose: To use dual-input tracer kinetic modeling of the lung for mapping spatial heterogeneity of various kinetic parameters in malignant MPM Methods: Six MPM patients received DCE-MRI as part of their radiation therapy simulation scan. 5 patients had the epitheloid subtype of MPM, while one was biphasic. A 3D fast-field echo sequence with TR/TE/Flip angle of 3.62ms/1.69ms/15° was used for DCE-MRI acquisition. The scan was collected for 5 minutes with a temporal resolution of 5-9 seconds depending on the spatial extent of the tumor. A principal component analysis-based groupwise deformable registration was used to co-register all the DCE-MRI series for motion compensation. All the images were analyzed using five different dual-input tracer kinetic models implemented in analog continuous-time formalism: the Tofts-Kety (TK), extended TK (ETK), two compartment exchange (2CX), adiabatic approximation to the tissue homogeneity (AATH), and distributed parameter (DP) models. The following parameters were computed for each model: total blood flow (BF), pulmonary flow fraction (γ), pulmonary blood flow (BF-pa), systemic blood flow (BF-a), blood volume (BV), mean transit time (MTT), permeability-surface area product (PS), fractional interstitial volume (vi), extraction fraction (E), volume transfer constant (Ktrans) and efflux rate constant (kep). Results: Although the majority of patients had epitheloid histologies, kinetic parameter values varied across different models. One patient showed a higher total BF value in all models among the epitheloid histologies, although the γ value was varying among these different models. In one tumor with a large area of necrosis, the TK and ETK models showed higher E, Ktrans, and kep values and lower interstitial volume as compared to AATH and DP and 2CX models. Kinetic parameters such as BF-pa, BF-a, PS, Ktrans values were higher in surviving group compared to non-surviving group across most models. Conclusion: Dual-input tracer

New sesquiterpenes from Euonymus europaeus (Celastraceae).

Science.gov (United States)

Descoins, Charles; Bazzocchi, Isabel López; Ravelo, Angel Gutiérrez

2002-02-01

A new sesquiterpene evoninate alkaloid (1), and two sesquiterpenes (2, 3) with a dihydro-beta-agarofuran skeleton, along with three known sesquiterpenes (4-6), were isolated from the seeds of Euonymus europaeus. Their structures were elucidated by high resolution mass analysis, and one- and two-dimensional (1D and 2D) NMR spectroscopy, including homonuclear and heteronuclear correlation [correlation spectroscopy (COSY), rotating frame Overhauser enhancement spectroscopy (ROESY), heteronuclear single quantum coherence (HSQC), and heteronuclear multiple bond correlation (HMBC)] experiments.

Dual source multidetector CT-angiography before transcatheter aortic valve implantation (TAVI) using a high-pitch spiral acquisition mode

Energy Technology Data Exchange (ETDEWEB)

Wuest, W.; Anders, K.; May, M.S.; Uder, M. [University of Erlangen, Department of Radiology, Erlangen (Germany); Schuhbaeck, A.; Gauss, S.; Marwan, M.; Arnold, M.; Muschiol, G.; Daniel, W.G.; Achenbach, S. [University of Erlangen, Department of Cardiology, Erlangen (Germany); Ensminger, S. [University of Erlangen, Department of Cardiac Surgery, Erlangen (Germany)

2012-01-15

Transcatheter Aortic Valve Implantation (TAVI) is an alternative to surgical valve replacement in high risk patients. Angiography of the aortic root, aorta and iliac arteries is required to select suitable candidates, but contrast agents can be harmful due to impaired renal function. We evaluated ECG-triggered high-pitch spiral dual source Computed Tomography (CT) with minimized volume of contrast agent to assess aortic root anatomy and vascular access. 42 patients (82 {+-} 6 years) scheduled for TAVI underwent dual source (DS) CT angiography (CTA) of the aorta using a prospectively ECG-triggered high-pitch spiral mode (pitch = 3.4) with 40 mL iodinated contrast agent. We analyzed aortic root/iliac dimensions, attenuation, contrast to noise ratio (CNR), image noise and radiation exposure. Aortic root/iliac dimensions and distance of coronary ostia from the annulus could be determined in all cases. Mean aortic and iliac artery attenuation was 320 {+-} 70 HU and 340 {+-} 77 HU. Aortic/iliac CNR was 21.7 {+-} 6.8 HU and 14.5 {+-} 5.4 HU using 100 kV (18.8 {+-} 4.1 HU and 8.7 {+-} 2.6 HU using 120 kV). Mean effective dose was 4.5 {+-} 1.2 mSv. High-pitch spiral DSCTA can be used to assess the entire aorta and iliac arteries in TAVI candidates with a low volume of contrast agent while preserving diagnostic image quality. (orig.)

Dual EC : a standardized back door

NARCIS (Netherlands)

Bernstein, D.J.; Lange, T.; Niederhagen, R.F.

2015-01-01

Dual EC is an algorithm to compute pseudorandom numbers starting from some random input. Dual EC was standardized by NIST, ANSI, and ISO among other algorithms to generate pseudorandom numbers. For a long time this algorithm was considered suspicious -- the entity designing the algorithm could have

Dual-Career Couples: Keeping Them Together.

Science.gov (United States)

Wolf-Wendel, Lisa E.; Twombly, Susan; Rice, Suzanne

2000-01-01

Reports results of a survey of 360 chief academic officers at member institutions of the American Association of Colleges and Universities regarding their policies and practices for assisting dual-career couples. Examines the motivations, barriers, consequences, and policy implications of institutional responses to dual-career couples. (DB)

A computer-aided system for automatic extraction of femur neck trabecular bone architecture using isotropic volume construction from clinical hip computed tomography images.

Science.gov (United States)

Vivekanandhan, Sapthagirivasan; Subramaniam, Janarthanam; Mariamichael, Anburajan

2016-10-01

Hip fractures due to osteoporosis are increasing progressively across the globe. It is also difficult for those fractured patients to undergo dual-energy X-ray absorptiometry scans due to its complicated protocol and its associated cost. The utilisation of computed tomography for the fracture treatment has become common in the clinical practice. It would be helpful for orthopaedic clinicians, if they could get some additional information related to bone strength for better treatment planning. The aim of our study was to develop an automated system to segment the femoral neck region, extract the cortical and trabecular bone parameters, and assess the bone strength using an isotropic volume construction from clinical computed tomography images. The right hip computed tomography and right femur dual-energy X-ray absorptiometry measurements were taken from 50 south-Indian females aged 30-80 years. Each computed tomography image volume was re-constructed to form isotropic volumes. An automated system by incorporating active contour models was used to segment the neck region. A minimum distance boundary method was applied to isolate the cortical and trabecular bone components. The trabecular bone was enhanced and segmented using trabecular enrichment approach. The cortical and trabecular bone features were extracted and statistically compared with dual-energy X-ray absorptiometry measured femur neck bone mineral density. The extracted bone measures demonstrated a significant correlation with neck bone mineral density (r > 0.7, p computed tomography images scanned with low dose could eventually be helpful in osteoporosis diagnosis and its treatment planning. © IMechE 2016.

Dynamical chiral-symmetry breaking in dual QCD

International Nuclear Information System (INIS)

Krein, G.; Williams, A.G.

1991-01-01

We have extended recent studies by Baker, Ball, and Zachariasen (BBZ) of dynamical chiral-symmetry breaking in dual QCD. Specifically, we have taken dual QCD to specify the nonperturbative infrared nature of the quark-quark interaction and then we have smoothly connected onto this the known leading-log perturbative QCD interaction in the ultraviolet region. In addition, we have solved for a momentum-dependent self-energy and have used the complete lowest-order dual QCD quark-quark interaction. We calculate the quark condensate left-angle bar qq right-angle and the pion decay constant f π within this model. We find that the dual QCD parameters needed to give acceptable results are reasonably consistent with those extracted from independent physical considerations by BBZ

The WA105-3x1x1 m3 dual phase LAr-TPC demonstrator

CERN Document Server

Murphy, Sebastien

2016-11-15

The dual phase Liquid Argon Time Projection Chamber (LAr TPC) is the state-of-art technology for neutrino detection thanks to its superb 3D tracking and calorimetry performance. Its main feature is the charge amplification in gas argon which provides excellent signal-to-noise ratio. Electrons produced in the liquid argon are extracted in the gas phase. Here, a readout plane based on Large Electron Multiplier detectors provides amplification of the charges before its collection onto an anode with strip readout. The charge amplification enables constructing fully homoge- nous giant LAr-TPCs with tuneable gain, excellent charge imaging performance and increased sensitivity to low energy events. Following a staged approach the WA105 collaboration is con- structing a dual phase LAr-TPC with an active volume of 3x1x1m3 that will soon be tested with cosmic rays. Its construction and operation aims to test scalable solutions for the crucial aspects of this technology: ultra high argon purity in non-evacuable tank, la...

Experimental investigation and combustion analysis of a direct injection dual-fuel diesel-natural gas engine

Energy Technology Data Exchange (ETDEWEB)

Carlucci, A.P.; De Risi, A.; Laforgia, D.; Naccarato, F. [Department of Engineering for Innovation, University of Salento, CREA, via per Arnesano, 73100 Lecce (Italy)

2008-02-15

A single-cylinder diesel engine has been converted into a dual-fuel engine to operate with natural gas together with a pilot injection of diesel fuel used to ignite the CNG-air charge. The CNG was injected into the intake manifold via a gas injector on purpose designed for this application. The main performance of the gas injector, such as flow coefficient, instantaneous mass flow rate, delay time between electrical signal and opening of the injector, have been characterized by testing the injector in a constant-volume optical vessel. The CNG jet structure has also been characterized by means of shadowgraphy technique. The engine, operating in dual-fuel mode, has been tested on a wide range of operating conditions spanning different values of engine load and speed. For all the tested operating conditions, the effect of CNG and diesel fuel injection pressure, together with the amount of fuel injected during the pilot injection, were analyzed on the combustion development and, as a consequence, on the engine performance, in terms of specific emission levels and fuel consumption. (author)

Dual-energy subtraction radiography of the breast

International Nuclear Information System (INIS)

Asaga, Taro; Masuzawa, Chihiro; Kawahara, Satoru; Motohashi, Hisahiko; Okamoto, Takashi; Tamura, Nobuo

1988-01-01

Dual-energy projection radiography was applied to breast examination. To perform the dual-energy subtraction radiography using a digital radiography unit, high and low-energy exposures were made at an appropriate time interval under differing X-ray exposure conditions. Dual-energy subtraction radiography was performed in 41 cancer patients in whom the tumor shadow was equivocal or the border of cancer infiltration was not clearly demonstrated by compression mammography, and 15 patients with benign diseases such as fibrocystic disease, cyst and fibroadenoma. In 21 cases out of the 41 cancer patients, the dual-energy subtraction radiography clearly visualized the malignant tumor shadows and the border of cancer infiltration and the daughter nodules by removing the shadows of normal mammary gland. On the other hand, beign diseases such as fibrocystic disease and cyst could be diagnosed as such, because the tumor shadow and the irregularly concentrated image of mammary gland disappeared by the dual-energy subtraction. These results suggest that this new technique will be useful in examination of breast masses. (author)

Dual-energy subtraction radiography of the breast

Energy Technology Data Exchange (ETDEWEB)

Asaga, Taro; Masuzawa, Chihiro; Kawahara, Satoru; Motohashi, Hisahiko; Okamoto, Takashi; Tamura, Nobuo

1988-06-01

Dual-energy projection radiography was applied to breast examination. To perform the dual-energy subtraction radiography using a digital radiography unit, high and low-energy exposures were made at an appropriate time interval under differing X-ray exposure conditions. Dual-energy subtraction radiography was performed in 41 cancer patients in whom the tumor shadow was equivocal or the border of cancer infiltration was not clearly demonstrated by compression mammography, and 15 patients with benign diseases such as fibrocystic disease, cyst and fibroadenoma. In 21 cases out of the 41 cancer patients, the dual-energy subtraction radiography clearly visualized the malignant tumor shadows and the border of cancer infiltration and the daughter nodules by removing the shadows of normal mammary gland. On the other hand, beign diseases such as fibrocystic disease and cyst could be diagnosed as such, because the tumor shadow and the irregularly concentrated image of mammary gland disappeared by the dual-energy subtraction. These results suggest that this new technique will be useful in examination of breast masses.

An unstructured-mesh finite-volume MPDATA for compressible atmospheric dynamics

International Nuclear Information System (INIS)

Kühnlein, Christian; Smolarkiewicz, Piotr K.

2017-01-01

An advancement of the unstructured-mesh finite-volume MPDATA (Multidimensional Positive Definite Advection Transport Algorithm) is presented that formulates the error-compensative pseudo-velocity of the scheme to rely only on face-normal advective fluxes to the dual cells, in contrast to the full vector employed in previous implementations. This is essentially achieved by expressing the temporal truncation error underlying the pseudo-velocity in a form consistent with the flux-divergence of the governing conservation law. The development is especially important for integrating fluid dynamics equations on non-rectilinear meshes whenever face-normal advective mass fluxes are employed for transport compatible with mass continuity—the latter being essential for flux-form schemes. In particular, the proposed formulation enables large-time-step semi-implicit finite-volume integration of the compressible Euler equations using MPDATA on arbitrary hybrid computational meshes. Furthermore, it facilitates multiple error-compensative iterations of the finite-volume MPDATA and improved overall accuracy. The advancement combines straightforwardly with earlier developments, such as the nonoscillatory option, the infinite-gauge variant, and moving curvilinear meshes. A comprehensive description of the scheme is provided for a hybrid horizontally-unstructured vertically-structured computational mesh for efficient global atmospheric flow modelling. The proposed finite-volume MPDATA is verified using selected 3D global atmospheric benchmark simulations, representative of hydrostatic and non-hydrostatic flow regimes. Besides the added capabilities, the scheme retains fully the efficacy of established finite-volume MPDATA formulations.

An unstructured-mesh finite-volume MPDATA for compressible atmospheric dynamics

Energy Technology Data Exchange (ETDEWEB)

Kühnlein, Christian, E-mail: christian.kuehnlein@ecmwf.int; Smolarkiewicz, Piotr K., E-mail: piotr.smolarkiewicz@ecmwf.int

2017-04-01

An advancement of the unstructured-mesh finite-volume MPDATA (Multidimensional Positive Definite Advection Transport Algorithm) is presented that formulates the error-compensative pseudo-velocity of the scheme to rely only on face-normal advective fluxes to the dual cells, in contrast to the full vector employed in previous implementations. This is essentially achieved by expressing the temporal truncation error underlying the pseudo-velocity in a form consistent with the flux-divergence of the governing conservation law. The development is especially important for integrating fluid dynamics equations on non-rectilinear meshes whenever face-normal advective mass fluxes are employed for transport compatible with mass continuity—the latter being essential for flux-form schemes. In particular, the proposed formulation enables large-time-step semi-implicit finite-volume integration of the compressible Euler equations using MPDATA on arbitrary hybrid computational meshes. Furthermore, it facilitates multiple error-compensative iterations of the finite-volume MPDATA and improved overall accuracy. The advancement combines straightforwardly with earlier developments, such as the nonoscillatory option, the infinite-gauge variant, and moving curvilinear meshes. A comprehensive description of the scheme is provided for a hybrid horizontally-unstructured vertically-structured computational mesh for efficient global atmospheric flow modelling. The proposed finite-volume MPDATA is verified using selected 3D global atmospheric benchmark simulations, representative of hydrostatic and non-hydrostatic flow regimes. Besides the added capabilities, the scheme retains fully the efficacy of established finite-volume MPDATA formulations.

Intermediate mass distribution of the dual resonance pomeron

International Nuclear Information System (INIS)

Chiu, C.B.; Matsuda, S.

1978-01-01

The intermediate mass distribution of the dual resonance pomeron is determined at the one-loop level and it is shown that the mass distribution obtained is remarkably similar to a suitably defined mass distribution in the dual multiperipheral model. Thus it is suggestive to identify the intermediate states of the dual resonance pomeron with multiperipheral processes. (Auth.)

Synthetic CT: Simulating low dose single and dual energy protocols from a dual energy scan

International Nuclear Information System (INIS)

Wang, Adam S.; Pelc, Norbert J.

2011-01-01

Purpose: The choice of CT protocol can greatly impact patient dose and image quality. Since acquiring multiple scans at different techniques on a given patient is undesirable, the ability to predict image quality changes starting from a high quality exam can be quite useful. While existing methods allow one to generate simulated images of lower exposure (mAs) from an acquired CT exam, the authors present and validate a new method called synthetic CT that can generate realistic images of a patient at arbitrary low dose protocols (kVp, mAs, and filtration) for both single and dual energy scans. Methods: The synthetic CT algorithm is derived by carefully ensuring that the expected signal and noise are accurate for the simulated protocol. The method relies on the observation that the material decomposition from a dual energy CT scan allows the transmission of an arbitrary spectrum to be predicted. It requires an initial dual energy scan of the patient to either synthesize raw projections of a single energy scan or synthesize the material decompositions of a dual energy scan. The initial dual energy scan contributes inherent noise to the synthesized projections that must be accounted for before adding more noise to simulate low dose protocols. Therefore, synthetic CT is subject to the constraint that the synthesized data have noise greater than the inherent noise. The authors experimentally validated the synthetic CT algorithm across a range of protocols using a dual energy scan of an acrylic phantom with solutions of different iodine concentrations. An initial 80/140 kVp dual energy scan of the phantom provided the material decomposition necessary to synthesize images at 100 kVp and at 120 kVp, across a range of mAs values. They compared these synthesized single energy scans of the phantom to actual scans at the same protocols. Furthermore, material decompositions of a 100/120 kVp dual energy scan are synthesized by adding correlated noise to the initial material

Myocardial perfusion imaging with dual energy CT

Energy Technology Data Exchange (ETDEWEB)

Jin, Kwang Nam [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiology, SMG-SNU Boramae Medical Center, Seoul (Korea, Republic of); De Cecco, Carlo N. [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Caruso, Damiano [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiological Sciences, Oncology and Pathology, University of Rome “Sapienza”, Rome (Italy); Tesche, Christian [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Cardiology and Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich (Germany); Spandorfer, Adam; Varga-Szemes, Akos [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States)

2016-10-15

Highlights: • Stress dual-energy sCTMPI offers the possibility to directly detect the presence of myocardial perfusion defects. • Stress dual-energy sCTMPI allows differentiating between reversible and fixed myocardial perfusion defects. • The combination of coronary CT angiography and dual-energy sCTMPI can improve the ability of CT to detect hemodynamically relevant coronary artery disease. - Abstract: Dual-energy CT (DECT) enables simultaneous use of two different tube voltages, thus different x-ray absorption characteristics are acquired in the same anatomic location with two different X-ray spectra. The various DECT techniques allow material decomposition and mapping of the iodine distribution within the myocardium. Static dual-energy myocardial perfusion imaging (sCTMPI) using pharmacological stress agents demonstrate myocardial ischemia by single snapshot images of myocardial iodine distribution. sCTMPI gives incremental values to coronary artery stenosis detected on coronary CT angiography (CCTA) by showing consequent reversible or fixed myocardial perfusion defects. The comprehensive acquisition of CCTA and sCTMPI offers extensive morphological and functional evaluation of coronary artery disease. Recent studies have revealed that dual-energy sCTMPI shows promising diagnostic accuracy for the detection of hemodynamically significant coronary artery disease compared to single-photon emission computed tomography, invasive coronary angiography, and cardiac MRI. The aim of this review is to present currently available DECT techniques for static myocardial perfusion imaging and recent clinical applications and ongoing investigations.

QCD Dual

DEFF Research Database (Denmark)

Sannino, Francesco

2009-01-01

We uncover a novel solution of the 't Hooft anomaly matching conditions for QCD. Interestingly in the perturbative regime the new gauge theory, if interpreted as a possible QCD dual, predicts the critical number of flavors above which QCD in the nonperturbative regime, develops an infrared stable...

SU-G-IeP2-15: Virtual Insertion of Digital Kidney Stones Into Dual-Source, Dual- Energy CT Projection Data

International Nuclear Information System (INIS)

Ferrero, A; Chen, B; Huang, A; Montoya, J; Yu, L; McCollough, C

2016-01-01

Purpose: In order to investigate novel methods to more accurately estimate the mineral composition of kidney stones using dual energy CT, it is desirable to be able to combine digital stones of known composition with actual phantom and patient scan data. In this work, we developed and validated a method to insert digital kidney stones into projection data acquired on a dual-source, dual-energy CT system. Methods: Attenuation properties of stones of different mineral composition were computed using tabulated mass attenuation coefficients, the chemical formula for each stone type, and the effective beam energy at each evaluated tube potential. A previously developed method to insert lesions into x-ray CT projection data was extended to include simultaneous dual-energy CT projections acquired on a dual-source gantry (Siemens Somatom Flash). Digital stones were forward projected onto both detectors and the resulting projections added to the physically acquired sinogram data. To validate the accuracy of the technique, digital stones were inserted into different locations in the ACR CT accreditation phantom; low and high contrast resolution, CT number accuracy and noise properties were compared before and after stone insertion. The procedure was repeated for two dual-energy tube potential pairs in clinical use on the scanner, 80/Sn140 kV and 100/Sn140 kV, respectively. Results: The images reconstructed after the insertion of digital kidney stones were consistent with the images reconstructed from the scanner. The largest average CT number difference for the 4 insert in the CT number accuracy module of the phantom was 3 HU. Conclusion: A framework was developed and validated for the creation of digital kidney stones of known mineral composition, and their projection-domain insertion into commercial dual-source, dual-energy CT projection data. This will allow a systematic investigation of the impact of scan and reconstruction parameters on stone attenuation and dual

Method and system for dual resolution translation stage

Science.gov (United States)

Halpin, John Michael

2014-04-22

A dual resolution translation stage includes a stage assembly operable to receive an optical element and a low resolution adjustment device mechanically coupled to the stage assembly. The dual resolution stage also includes an adjustable pivot block mechanically coupled to the stage assembly. The adjustable pivot block includes a pivot shaft. The dual resolution stage further includes a lever arm mechanically coupled to the adjustable pivot block. The lever arm is operable to pivot about the pivot shaft. The dual resolution stage additionally includes a high resolution adjustment device mechanically coupled to the lever arm and the stage assembly.

Musical expertise has minimal impact on dual task performance.

Science.gov (United States)

Cocchini, Gianna; Filardi, Maria Serena; Crhonkova, Marcela; Halpern, Andrea R

2017-05-01

Studies investigating effect of practice on dual task performance have yielded conflicting findings, thus supporting different theoretical accounts about the organisation of attentional resources when tasks are performed simultaneously. Because practice has been proven to reduce the demand of attention for the trained task, the impact of long-lasting training on one task is an ideal way to better understand the mechanisms underlying dual task decline in performance. Our study compared performance during dual task execution in expert musicians compared to controls with little if any musical experience. Participants performed a music recognition task and a visuo-spatial task separately (single task) or simultaneously (dual task). Both groups showed a significant but similar performance decline during dual tasks. In addition, the two groups showed a similar decline of dual task performance during encoding and retrieval of the musical information, mainly attributed to a decline in sensitivity. Our results suggest that attention during dual tasks is similarly distributed by expert and non-experts. These findings are in line with previous studies showing a lack of sensitivity to difficulty and lack of practice effect during dual tasks, supporting the idea that different tasks may rely on different and not-sharable attentional resources.

7 CFR 7.17 - Dual office.

Science.gov (United States)

2010-01-01

... 7 Agriculture 1 2010-01-01 2010-01-01 false Dual office. 7.17 Section 7.17 Agriculture Office of... STATE, COUNTY AND COMMUNITY COMMITTEES § 7.17 Dual office. (a) County committee membership. A member of... any other county office employee. (b) Community committee membership. A member of the community...

Symmetries of Taub-NUT dual metrics

International Nuclear Information System (INIS)

Baleanu, D.; Codoban, S.

1998-01-01

Recently geometric duality was analyzed for a metric which admits Killing tensors. An interesting example arises when the manifold has Killing-Yano tensors. The symmetries of the dual metrics in the case of Taub-NUT metric are investigated. Generic and non-generic symmetries of dual Taub-NUT metric are analyzed

Dual throat engine design for a SSTO launch vehicle

Science.gov (United States)

Obrien, C. J.; Salmon, J. W.

1980-01-01

A propulsion system analysis of a dual fuel, dual throat engine for launch vehicle application was conducted. Basic dual throat engine characterization data are presented to allow vehicle optimization studies to be conducted. A preliminary baseline engine system was defined. Dual throat engine performance, envelope, and weight parametric data were generated over the parametric range of thrust from 890 to 8896 KN (200K to 2M lb-force), chamber pressure from 6.89 million to 34.5 million N/sq m (1000 to 5000 psia) thrust ratio from 1.2 to 5, and a range of mixture ratios for the two tripropellant combinations: LO2/RP-1 + LH2 and LO2/LCH4 + LH2. The results of the study indicate that the dual fuel dual throat engine is a viable single stage to orbit candidate.

Block copolymer/homopolymer dual-layer hollow fiber membranes

KAUST Repository

Hilke, Roland

2014-12-01

We manufactured the first time block copolymer dual-layer hollow fiber membranes and dual layer flat sheet membranes manufactured by double solution casting and phase inversion in water. The support porous layer was based on polystyrene and the selective layer with isopores was formed by micelle assembly of polystyrene-. b-poly-4-vinyl pyridine. The dual layers had an excellent interfacial adhesion and pore interconnectivity. The dual membranes showed pH response behavior like single layer block copolymer membranes with a low flux for pH values less than 3, a fast increase between pH4 and pH6 and a constant high flux level for pH values above 7. The dry/wet spinning process was optimized to produce dual layer hollow fiber membranes with polystyrene internal support layer and a shell block copolymer selective layer.

Dual-Energy Computed Tomography: Image Acquisition, Processing, and Workflow.

Science.gov (United States)

Megibow, Alec J; Kambadakone, Avinash; Ananthakrishnan, Lakshmi

2018-07-01

Dual energy computed tomography has been available for more than 10 years; however, it is currently on the cusp of widespread clinical use. The way dual energy data are acquired and assembled must be appreciated at the clinical level so that the various reconstruction types can extend its diagnostic power. The type of scanner that is present in a given practice dictates the way in which the dual energy data can be presented and used. This article compares and contrasts how dual source, rapid kV switching, and spectral technologies acquire and present dual energy reconstructions to practicing radiologists. Copyright © 2018 Elsevier Inc. All rights reserved.

Dual antiplatelet treatment in patients candidates for abdominal surgery.

Science.gov (United States)

Illuminati, Giulio; Ceccanei, Gianluca; Pacilè, Maria A; Pizzardi, Giulia; Palumbo, Piergaspare; Vietri, Francesco

2013-01-01

With the increasing diffusion of percutaneous interventions (PCI), surgeons are often faced with the problem of operating on patients under dual antiplatelet treatment. Replacing dual antiplatelet regiment with low molecular weight heparin may expose to the abrupt thrombosis of coronary stent and massive myocardial infarction. The purpose of this study was to test the hypothesis that abdominal operations can be safely performed under dual antiplatelet treatment. Eleven patients underwent 5 colectomies, 3 nefrectomies, 2 gastrectomies and 1 hysterectomy under aspirin and plavix without any significant perioperative hemorrhage. These preliminary results show that abdominal operations can be safely performed under dual antiplatelet regimen. Abdominal surgery, Dual antiplatelet treatment.

IAEA's dual function

International Nuclear Information System (INIS)

1967-01-01

'A factor of paramount importance is the dual nature of atomic energy, which is reflected in the dual function of the Agency; not only to promote, but also to safeguard the peaceful uses of atomic energy'. In taking the above statement as a theme in his address to the 1474th Plenary Meeting of the United Nations General Assembly (22nd November), the Director General, Dr. Sigvard Eklund, went on to speak of a few of the many areas in which society was feeling the impact of atomic energy. During the discussion which followed his report on the Agency's work nearly all speakers referred to the importance of the safeguards system as well as to positive achievements in developing nuclear potential for peaceful purposes

Dual frequency comb metrology with one fiber laser

Science.gov (United States)

Zhao, Xin; Takeshi, Yasui; Zheng, Zheng

2016-11-01

Optical metrology techniques based on dual optical frequency combs have emerged as a hotly studied area targeting a wide range of applications from optical spectroscopy to microwave and terahertz frequency measurement. Generating two sets of high-quality comb lines with slightly different comb-tooth spacings with high mutual coherence and stability is the key to most of the dual-comb schemes. The complexity and costs of such laser sources and the associated control systems to lock the two frequency combs hinder the wider adoption of such techniques. Here we demonstrate a very simple and rather different approach to tackle such a challenge. By employing novel laser cavity designs in a mode-locked fiber laser, a simple fiber laser setup could emit dual-comb pulse output with high stability and good coherence between the pulse trains. Based on such lasers, comb-tooth-resolved dual-comb optical spectroscopy is demonstrated. Picometer spectral resolving capability could be realized with a fiber-optic setup and a low-cost data acquisition system and standard algorithms. Besides, the frequency of microwave signals over a large range can be determined based on a simple setup. Our results show the capability of such single-fiber-laser-based dual-comb scheme to reduce the complexity and cost of dual-comb systems with excellent quality for different dual-comb applications.

Dual protection: more needed than practised or understood.

Science.gov (United States)

Berer, Marge

2006-11-01

Although non-barrier contraceptive use has become a global norm, unprotected sex in relation to sexually transmitted infections remains the norm almost everywhere. Dual protection is protection from unwanted pregnancy, HIV and other sexually transmitted infections, and is a form of safer sex for heterosexual couples that is more needed than practised or understood. This paper draws on a review of the literature in family planning, obstetrics and gynaecology, and AIDS-related journals from 1998 to early 2005. Definitions of dual protection, found mainly in family planning literature, are very narrow. Condoms remain the mainstay of dual protection, but the aim of this paper is to provide an expanded list of dual protection methods to show that there is a range of options. These include non-penetrative sex and the increasing use of condoms with the back-up of emergency contraception on the part of young people. The fact that people may fail to use dual protection consistently and correctly is not a valid reason not to promote it. It is never too late for those providing family planning and STI/HIV prevention services to start promoting condoms and dual protection. In the long-term, the development of highly efficacious and highly acceptable methods of dual protection is an urgent research priority, starting with a wider range of condoms that will appeal to more people.

Dual potentials in non-Abelian gauge theories

International Nuclear Information System (INIS)

Caticha, A.

1988-01-01

Motivated by the possibility that confinement and superconductivity are similar phenomena, dual potentials are introduced into Yang-Mills theory in two different ways. Both are extensions of Zwanziger's two-potential formalism for Abelian charges and monopoles to the non-Abelian case. In the first approach the dual potentials carry a color index and there is a rather simple, although nonlocal, dual-variable formulation. In the second approach dual variables are introduced into the so-called Abelian projection of the SU(2) Yang-Mills theory. An interesting feature is that the quartic contact interactions are absent and there is a special gauge choice for which the theory takes on a ''purely electromagnetic'' form. More important, however, is the appearance of an additional Abelian magnetic gauge symmetry the dynamical breaking of which may be associated with confinement

Evaluation of an exposed-radiation dose on a dual-source cardiac computed tomography examination with a prospective electrocardiogram-gated fast dual spiral scan

International Nuclear Information System (INIS)

Matsubara, Kosuke; Koshida, Kichiro; Koshida, Haruka; Sakuta, Keita; Hayashi, Hiroyuki; Takata, Tadanori; Horii, Junsei; Kawai, Keiichi; Yamamoto, Tomoyuki

2012-01-01

We evaluated exposed-radiation doses on dual-source cardiac computed tomography (CT) examinations with prospective electrocardiogram (ECG)-gated fast dual spiral scans. After placing dosimeters at locations corresponding to each of the thoracic organs, prospective ECG-gated fast dual spirals and retrospective ECG-gated dual spiral scans were performed to measure the absorbed dose of each organ. In the prospective ECG-gated fast dual spiral scans, the average absorbed doses were 5.03 mGy for the breast, 9.96 mGy for the heart, 6.60 mGy for the lung, 6.48 mGy for the bone marrow, 9.73 mGy for the thymus, and 4.58 mGy for the skin. These values were about 5% of the absorbed doses for the retrospective ECG-gated dual spiral scan. However, the absorbed dose differed greatly at each scan, especially in the external organs such as the breast. For effective and safe use of the prospective ECG-gated fast dual spiral scan, it is necessary to understand these characteristics sufficiently. (author)

Limitations in dual-task performance

OpenAIRE

Pannebakker, Merel Mathilde

2009-01-01

In this thesis, the effect of information-processing overload on working-memory dependent information processing was examined using dual-task paradigms. The experiments described strengthen the importance of a functional explanation for dual-task limitations. First, it showed evidence for a unified coding medium (as put forward in the theory of event coding; Hommel, Müsseler, Aschersleben, & Prinz, 2001) in which features, operations and responses are available and can influence each other. A...

Dual-wavelength OR-PAM with compressed sensing for cell tracking in a 3D cell culture system

Science.gov (United States)

Huang, Rou-Xuan; Fu, Ying; Liu, Wang; Ma, Yu-Ting; Hsieh, Bao-Yu; Chen, Shu-Ching; Sun, Mingjian; Li, Pai-Chi

2018-02-01

Monitoring dynamic interactions of T cells migrating toward tumor is beneficial to understand how cancer immunotherapy works. Optical-resolution photoacoustic microscope (OR-PAM) can provide not only high spatial resolution but also deeper penetration than conventional optical microscopy. With the aid of exogenous contrast agents, the dual-wavelength OR-PAM can be applied to map the distribution of CD8+ cytotoxic T lymphocytes (CTLs) with gold nanospheres (AuNS) under 523nm laser irradiation and Hepta1-6 tumor spheres with indocyanine green (ICG) under 800nm irradiation. However, at 1K laser PRF, it takes approximately 20 minutes to obtain a full sample volume of 160 × 160 × 150 μm3 . To increase the imaging rate, we propose a random non-uniform sparse sampling mechanism to achieve fast sparse photoacoustic data acquisition. The image recovery process is formulated as a low-rank matrix recovery (LRMR) based on compressed sensing (CS) theory. We show that it could be stably recovered via nuclear-norm minimization optimization problem to maintain image quality from a significantly fewer measurement. In this study, we use the dual-wavelength OR-PAM with CS to visualize T cell trafficking in a 3D culture system with higher temporal resolution. Data acquisition time is reduced by 40% in such sample volume where sampling density is 0.5. The imaging system reveals the potential to understand the dynamic cellular process for preclinical screening of anti-cancer drugs.

Dual-source CT in chest pain diagnosis

International Nuclear Information System (INIS)

Johnson, Thorsten R.C.; Nikolaou, K.; Fink, C.; Rist, C.; Reiser, M.F.; Becker, C.R.; Becker, A.; Knez, A.

2007-01-01

With the depiction of pulmonary arteries, coronary arteries, and the aorta, CT angiography of the chest offers a comprehensive diagnostic work-up of unclear chest pain. The aim of this study was to assess the diagnostic accuracy of dual-source CT in this patient group. A total of 47 patients suffering from unclear chest pain were examined with a Siemens Somatom Definition. Volume and flow of contrast media (Ultravist, Schering) were adapted to the body weight. The examinations were evaluated with regard to image quality and contrast opacification and to the diagnostic accuracy with reference to the final clinical diagnosis. Adequate contrast opacification was achieved in all examinations. The depiction of the coronary arteries was diagnostic in all cases. The cause of chest pain could be identified in 41 cases. Among the diagnoses were coronary and myocardial pathologies, valvular disease, aortic aneurysms and dissections, pulmonary embolism, and pneumonic consolidation. DSCT angiography of the chest offers a very good image quality even at high heart rates so that a high diagnostic accuracy is achieved in patients with acute chest pain. (orig.) [de

Dual Pathology of Mandible.

Science.gov (United States)

Rajurkar, Suday G; Deshpande, Mohan D; Kazi, Noaman; Jadhav, Dhanashree; Ranadive, Pallavi; Ingole, Snehal

2017-01-01

Aneurysmal Bone cyst (ABC)is a rare benign lesion of the bone which is infrequent in craniofacial region (12%). Rapid growth pattern causing bone expansion and facial asymmetry is a characteristic feature of ABC. Giant cell lesion is another distinct pathological entity. Here we present to you a rare case of dual pathology in an 11 year old female patient who presented with a large expansile lesion in the left hemimandible. All radiographic investigations were suggestive of ABC, aspiration of the lesion resulted in blood aspirate. However only after a histologic examination the dual nature of the lesion was revealed.

Single-Layer, Dual-Port, Dual-Band, and Orthogonal-Circularly Polarized Microstrip Antenna Array with Low Frequency Ratio

Directory of Open Access Journals (Sweden)

Min Wang

2018-01-01

Full Text Available A single-layer, dual-port, dual-band, and dual circularly polarized (CP microstrip array is designed for satellite communication in this paper. The operating frequencies are 8.2 and 8.6 GHz with a very low ratio of 1.05. First, a rectangular patch element is fed through microstrip lines at two orthogonal edges to excite two orthogonal dominant modes of TM01 and TM10. The very low frequency ratio can be realized with high polarization isolations. Then, a 2-by-2 dual-band dual-CP subarray is constructed by two independent sets of sequentially rotated (SR feed structures. An 8-by-8 array is designed on the single-layer thin substrate. Finally, by utilizing one-to-four power dividers and semirigid coaxial cables, a 16-by-16 array is developed to achieve higher gain. Measured results show that the 16-by-16 array has 15 dB return loss (RL bandwidths of 4.81% and 6.75% and 3 dB axial ratio (AR bandwidths of 2.84% and 1.57% in the lower and the upper bands, respectively. Isolations of 18.6 dB and 19.4 dB and peak gains of 25.1 dBic and 25.6 dBic are obtained at 8.2 and 8.6 GHz, respectively.

Exploiting Dual-Output Programmable Blocks to Balance Secure Dual-Rail Logics

Directory of Open Access Journals (Sweden)

Laurent Sauvage

2010-01-01

for such purposes. However, assessing the security level which can be achieved with them is an important issue, as it is directly related to the suitability to use commercial FPGA instead of proprietary custom FPGA for this kind of protection. In this article, we experimentally gave evidence that differential placement and routing of an FPGA implementation can be done with a granularity fine enough to improve the security gain. However, so far, this gain turned out to be lower for FPGAs than for ASICs. The solutions demonstrated in this article exploit the dual-output of modern FPGAs to achieve a better balance of dual-rail interconnections. However, we expect that an in-depth analysis of routing resources power consumption could still help reduce the interconnect differential leakage.

Fluorescence and Magnetic Resonance Dual-Modality Imaging-Guided Photothermal and Photodynamic Dual-Therapy with Magnetic Porphyrin-Metal Organic Framework Nanocomposites

Science.gov (United States)

Zhang, Hui; Li, Yu-Hao; Chen, Yang; Wang, Man-Man; Wang, Xue-Sheng; Yin, Xue-Bo

2017-03-01

Phototherapy shows some unique advantages in clinical application, such as remote controllability, improved selectivity, and low bio-toxicity, than chemotherapy. In order to improve the safety and therapeutic efficacy, imaging-guided therapy seems particularly important because it integrates visible information to speculate the distribution and metabolism of the probe. Here we prepare biocompatible core-shell nanocomposites for dual-modality imaging-guided photothermal and photodynamic dual-therapy by the in situ growth of porphyrin-metal organic framework (PMOF) on Fe3O4@C core. Fe3O4@C core was used as T2-weighted magnetic resonance (MR) imaging and photothermal therapy (PTT) agent. The optical properties of porphyrin were well remained in PMOF, and PMOF was therefore selected for photodynamic therapy (PDT) and fluorescence imaging. Fluorescence and MR dual-modality imaging-guided PTT and PDT dual-therapy was confirmed with tumour-bearing mice as model. The high tumour accumulation of Fe3O4@C@PMOF and controllable light excitation at the tumour site achieved efficient cancer therapy, but low toxicity was observed to the normal tissues. The results demonstrated that Fe3O4@C@PMOF was a promising dual-imaging guided PTT and PDT dual-therapy platform for tumour diagnosis and treatment with low cytotoxicity and negligible in vivo toxicity.

Gauge theory of weak, electromagnetic and dual electromagnetic interactions

International Nuclear Information System (INIS)

Soln, J.

1980-01-01

An SU 2 x U 1 algebra, in addition to the ordinary electric charge, also establishes the existence of the dual electric charge. This is taken as an indication of the existence of dual electromagnetic interactions in nature. Here, the unification of weak, electromagnetic and dual electromagnetic interactions is performed. The Yang-Mills-type group which contains the electromagnetic, dual electromagnetic and weak currents is SUsub(L,2) x U 1 x U' 1 . The masses of vector mesons are generated through the Higgs-Kibble mechanism. A simple consistency requirement suggests that dual electromagnetism and ordinary electromagnetism have the same strengths, leading the theory to a rather good agreement with experiments. (author)

Systematic Review to Inform Dual Tobacco Use Prevention.

Science.gov (United States)

Evans, William Douglas; Horn, Kimberly A; Gray, Tiffany

2015-10-01

With more tobacco products now available and heavily marketed, dual tobacco use is increasing among youth. We systematically reviewed literature on dual tobacco use interventions, with an emphasis on mass health communication strategies. The review identified 46 articles meeting initial criteria and ultimately included 8 articles. Included studies reported a mix of health communication and social marketing techniques. Although there is a body of research on dual tobacco use, there is limited literature describing interventions aimed at controlling it. Design and evaluation of such interventions showing reductions in dual use of cigarettes, smokeless, and alternative products would advance the field. Copyright © 2015 Elsevier Inc. All rights reserved.

Dual-role plasticizer and dispersant for ceramic layers

DEFF Research Database (Denmark)

2016-01-01

Thus, one aspect of the invention relates to a green ceramic layer comprising a ceramic material, a binder, and a dual-role dispersant and plasticizer, wherein said dual-role dispersant and plasticizer is an organic di- or tri-ester selected from compounds of formula (I), (II), (III) and (IV......). Another aspect of the present invention relates to a slurry for use in the manufacturing of a green ceramic layer comprising a ceramic material, a solvent, a binder, and a dual-role dispersant and plasticizer, wherein said dual role dispersant and plasticizer is an organic di- or tri- ester. Further...... aspects include uses of and methods of manufacturing said green ceramic layers....

CFT duals for extreme black holes

International Nuclear Information System (INIS)

Hartman, Thomas; Strominger, Andrew; Murata, Keiju; Nishioka, Tatsuma

2009-01-01

It is argued that the general four-dimensional extremal Kerr-Newman-AdS-dS black hole is holographically dual to a (chiral half of a) two-dimensional CFT, generalizing an argument given recently for the special case of extremal Kerr. Specifically, the asymptotic symmetries of the near-horizon region of the general extremal black hole are shown to be generated by a Virasoro algebra. Semiclassical formulae are derived for the central charge and temperature of the dual CFT as functions of the cosmological constant, Newton's constant and the black hole charges and spin. We then show, assuming the Cardy formula, that the microscopic entropy of the dual CFT precisely reproduces the macroscopic Bekenstein-Hawking area law. This CFT description becomes singular in the extreme Reissner-Nordstrom limit where the black hole has no spin. At this point a second dual CFT description is proposed in which the global part of the U(1) gauge symmetry is promoted to a Virasoro algebra. This second description is also found to reproduce the area law. Various further generalizations including higher dimensions are discussed.

Automatically sweeping dual-channel boxcar integrator

International Nuclear Information System (INIS)

Keefe, D.J.; Patterson, D.R.

1978-01-01

An automatically sweeping dual-channel boxcar integrator has been developed to automate the search for a signal that repeatedly follows a trigger pulse by a constant or slowly varying time delay when that signal is completely hidden in random electrical noise and dc-offset drifts. The automatically sweeping dual-channel boxcar integrator improves the signal-to-noise ratio and eliminates dc-drift errors in the same way that a conventional dual-channel boxcar integrator does, but, in addition, automatically locates the hidden signal. When the signal is found, its time delay is displayed with 100-ns resolution, and its peak value is automatically measured and displayed. This relieves the operator of the tedious, time-consuming, and error-prone search for the signal whenever the time delay changes. The automatically sweeping boxcar integrator can also be used as a conventional dual-channel boxcar integrator. In either mode, it can repeatedly integrate a signal up to 990 times and thus make accurate measurements of the signal pulse height in the presence of random noise, dc offsets, and unsynchronized interfering signals

Analytic continuation of dual Feynman amplitudes

International Nuclear Information System (INIS)

Bleher, P.M.

1981-01-01

A notion of dual Feynman amplitude is introduced and a theorem on the existence of analytic continuation of this amplitude from the convergence domain to the whole complex is proved. The case under consideration corresponds to massless power propagators and the analytic continuation is constructed on the propagators powers. Analytic continuation poles and singular set of external impulses are found explicitly. The proof of the theorem on the existence of analytic continuation is based on the introduction of α-representation for dual Feynman amplitudes. In proving, the so-called ''trees formula'' and ''trees-with-cycles formula'' are established that are dual by formulation to the trees and 2-trees formulae for usual Feynman amplitudes. (Auth.)

Metal oxide/hydroxide-coated dual-media filter for simultaneous removal of bacteria and heavy metals from natural waters.

Science.gov (United States)

Ahammed, M Mansoor; Meera, V

2010-09-15

The present study was conducted to compare the performance of a dual-media filter consisting of manganese oxide-coated (MOCS) and iron hydroxide-coated sand (IOCS) with that of IOCS filter and uncoated sand filter in treating water contaminated by microorganisms, heavy metals and turbidity with a view to its use in simple household water purification devices in developing countries. Long-duration column tests were conducted using two natural waters namely, roof-harvested rainwater and canal water. Performance of the filters showed that dual-media filter was more efficient in removing bacteria and heavy metals compared to IOCS filter, while uncoated sand filter showed very poor performance. The average effluent levels for dual-media filter when tested with rainwater were: turbidity 1.0+/-0.1 NTU; total coliforms 3+/-2 MPN/100 mL; heterotrophic plate count 170+/-20 CFU/mL; zinc 0.06+/-0.01 mg/L, while that for IOCS filter were: turbidity 1.0+/-0.1 NTU; total coliforms 4+/-2 MPN/100 mL; heterotrophic plate count 181+/-37 CFU/mL; zinc 0.20+/-0.07 mg/L. Similar results were obtained for canal water also. Up to 900 bed volumes (BV) could be treated without affecting the efficiency in the case of rainwater, while the filter operation had to be terminated after 500 BV due to excessive headloss in the case of canal water. The study thus showed the potential of the dual-media for use in low-cost household water filters for purification of natural waters. Copyright 2010 Elsevier B.V. All rights reserved.

Dual-window dual-bandwidth spectroscopic optical coherence tomography metric for qualitative scatterer size differentiation in tissues.

Science.gov (United States)

Tay, Benjamin Chia-Meng; Chow, Tzu-Hao; Ng, Beng-Koon; Loh, Thomas Kwok-Seng

2012-09-01

This study investigates the autocorrelation bandwidths of dual-window (DW) optical coherence tomography (OCT) k-space scattering profile of different-sized microspheres and their correlation to scatterer size. A dual-bandwidth spectroscopic metric defined as the ratio of the 10% to 90% autocorrelation bandwidths is found to change monotonically with microsphere size and gives the best contrast enhancement for scatterer size differentiation in the resulting spectroscopic image. A simulation model supports the experimental results and revealed a tradeoff between the smallest detectable scatterer size and the maximum scatterer size in the linear range of the dual-window dual-bandwidth (DWDB) metric, which depends on the choice of the light source optical bandwidth. Spectroscopic OCT (SOCT) images of microspheres and tonsil tissue samples based on the proposed DWDB metric showed clear differentiation between different-sized scatterers as compared to those derived from conventional short-time Fourier transform metrics. The DWDB metric significantly improves the contrast in SOCT imaging and can aid the visualization and identification of dissimilar scatterer size in a sample. Potential applications include the early detection of cell nuclear changes in tissue carcinogenesis, the monitoring of healing tendons, and cell proliferation in tissue scaffolds.

Accuracy of Combined Computed Tomography Colonography and Dual Energy Iiodine Map Imaging for Detecting Colorectal masses using High-pitch Dual-source CT.

Science.gov (United States)

Sun, Kai; Han, Ruijuan; Han, Yang; Shi, Xuesen; Hu, Jiang; Lu, Bin

2018-02-28

To evaluate the diagnostic accuracy of combined computed tomography colonography (CTC) and dual-energy iodine map imaging for detecting colorectal masses using high-pitch dual-source CT, compared with optical colonography (OC) and histopathologic findings. Twenty-eight consecutive patients were prospectively enrolled in this study. All patients were underwent contrast-enhanced CTC acquisition using dual-energy mode and OC and pathologic examination. The size of the space-occupied mass, the CT value after contrast enhancement, and the iodine value were measured and statistically compared. The sensitivity, specificity, accuracy rate, and positive predictive and negative predictive values of dual-energy contrast-enhanced CTC were calculated and compared between conventional CTC and dual-energy iodine images. The iodine value of stool was significantly lower than the colonic neoplasia (P dual-energy iodine maps imaging was 95.6% (95% CI = 77.9%-99.2%). The specificity of the two methods was 42.8% (95% CI = 15.4%-93.5%) and 100% (95% CI = 47.9%-100%; P = 0.02), respectively. Compared with optical colonography and histopathology, combined CTC and dual-energy iodine maps imaging can distinguish stool and colonic neoplasia, distinguish between benign and malignant tumors initially and improve the diagnostic accuracy of CTC for colorectal cancer screening.

Intensive lipid-lowering therapy with rosuvastatin stabilizes lipid-rich coronary plaques. Evaluation using dual-source computed tomography

International Nuclear Information System (INIS)

Soeda, Tsunenari; Uemura, Shiro; Okayama, Satoshi

2011-01-01

Clinical studies using invasive modalities have reported that statin therapy stabilizes coronary plaque vulnerability. The serial changes of lipid-rich coronary plaques (LRCPs) during rosuvastatin treatment were evaluated non-invasively in patients with acute coronary syndrome (ACS) using dual-source computed tomography (DSCT). A total of 11 consecutive ACS patients, and 13 LRCPs were serially evaluated on DSCT before and 24 weeks after rosuvastatin treatment. Compared with the baseline, there was no change in post-treatment minimal lumen diameter, lumen volume, or longitudinal length of LRCPs. By contrast, the ratio of lipid core volume to plaque volume significantly decreased from 48.0±9.9% to 43.7±10.6% (P=0.04), and plaque volume decreased from 144.5±85.5 mm 3 to 119.8±78.0 mm 3 (P=0.07). The remodeling index of target LRCPs significantly decreased from 1.16±0.10 to 1.06±0.12 (P=0.02). Percent reduction of plaque volume was significantly greater in patients with a lower ratio of low-density lipoprotein to high-density lipoprotein (L/H ratio ≤1.5) at follow-up than patients with higher L/H ratio (>1.5; median -31.7% vs. -6.8%, P=0.03). Rosuvastatin therapy reduced the volume of lipid cores and LRCPs and increased the CT attenuation value of LRCPs. DSCT is an effective modality for the non-invasive evaluation of LRCPs in patients with ACS. (author)

Pomelo peels-derived porous activated carbon microsheets dual-doped with nitrogen and phosphorus for high performance electrochemical capacitors

Science.gov (United States)

Wang, Zhen; Tan, Yongtao; Yang, Yunlong; Zhao, Xiaoning; Liu, Ying; Niu, Lengyuan; Tichnell, Brandon; Kong, Lingbin; Kang, Long; Liu, Zhen; Ran, Fen

2018-02-01

In this work, biomass pomelo peel is used to fabricate the porous activated carbon microsheets, and diammonium hydrogen phosphate (DHP) is employed to dual-dope carbon with nitrogen and phosphorus elements. With the benefit of DHP inducement and dual-doping of nitrogen and phosphorus, the prepared carbon material has a higher carbon yield, and exhibits higher specific surface area (about 807.7 m2/g), and larger pore volume (about 0.4378 cm3/g) with hierarchically structure of interconnected thin microsheets compared to the pristine carbon. The material exhibits not only high specific capacitance (240 F/g at 0.5 A/g), but also superior cycling performance (approximately 100% of capacitance retention after 10,000 cycles at 2 A/g) in 2 M KOH aqueous electrolyte. Furthermore, the assembled symmetric electrochemical capacitor in 1 M Na2SO4 aqueous electrolyte exhibits a high energy density of 11.7 Wh/kg at a power density of 160 W/kg.

A Novel Dual-Stage Hydrothermal Flow Reactor

DEFF Research Database (Denmark)

Hellstern, Henrik Christian; Becker, Jacob; Hald, Peter

2015-01-01

The dual-stage reactor is a novel continuous flow reactor with two reactors connected in series. It is designed for hydrothermal flow synthesis of nanocomposites, in which a single particle consists of multiple materials. The secondary material may protect the core nanoparticle from oxidation....... The dual-stage reactor combines the ability to produce advanced materials with an upscaled capacity in excess of 10 g/hour (dry mass). TiO2 was synthesized in the primary reactor and reproduced previous results. The dual-stage capability was succesfully demonstrated with a series of nanocomposites incl. Ti...

Dual approaches for defects condensation

Energy Technology Data Exchange (ETDEWEB)

Rougemont, Romulo; Grigorio, Leonardo de Souza; Wotzasek, Clovis [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); Guimaraes, Marcelo Santos [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil)

2009-07-01

Full text. Due to the fact that the QCD running coupling constant becomes larger as we go into the low energy (or large distance) limit of the theory, a perturbative treatment of its infrared (IR) region is impossible. In particular, a formal mathematical demonstration of color confinement and a complete physical understanding of the exact mechanism that confines quarks and gluons are two missing points in our current knowledge of the IR-QCD. It was known that due to the Meissner effect of expulsion of magnetic fields in a electric condensate that usual superconductors should confine magnetic monopoles. That point led to the conjecture that the QCD vacuum could be a condensate of chromomagnetic monopoles, a dual superconductor (DSC). Such a chromomagnetic condensate should be responsible for the dual Meissner effect which is expected to lead to the confinement of color charges immersed in this medium. In dual superconductor models of color confinement, magnetic monopoles appear as topological defects in points of the space where the abelian projection becomes singular. Also, condensation of other kinds of defects such as vortices in superfluids and line-like defects in solids are responsible for a great variety of phase transitions, which once more proves the relevance of the subject. In the present work we review two methods that allow us to approach the condensation of defects: the Kleinert Mechanism (KM) and the Julia-Toulouse Mechanism (JTM). We show that in the limit where the vortex gauge field goes to zero, which we identify as the signature of the condensation of defects in the dual picture, these are two equivalent dual prescriptions for obtaining an effective theory for a phase where defects are condensed, starting from the fundamental theory defined in the normal phase where defects are diluted. (author)

[Application of second generation dual-source computed tomography dual-energy scan mode in detecting pancreatic adenocarcinoma].

Science.gov (United States)

Xue, Hua-dan; Liu, Wei; Sun, Hao; Wang, Xuan; Chen, Yu; Su, Bai-yan; Sun, Zhao-yong; Chen, Fang; Jin, Zheng-yu

2010-12-01

To analyze the clinical value of multiple sequences derived from dual-source computed tomography (DSCT) dual-energy scan mode in detecting pancreatic adenocarcinoma. Totally 23 patients with clinically or pathologically diagnosed pancreatic cancer were enrolled in this retrospective study. DSCT (Definition Flash) was used and dual-energy scan mode was used in their pancreatic parenchyma phase scan (100kVp/230mAs and Sn140kVp/178mAs) . Mono-energetic 60kev, mono-energetic 80kev, mono-energetic 100kev, mono-energetic 120kev, linear blend image, non-linear blend image, and iodine map were acquired. pancreatic parenchyma-tumor CT value difference, ratio of tumor to pancreatic parenchyma, and pancreatic parenchyma-tumor contrast to noise ratio were calculated. One-way ANOVA was used for the comparison of diagnostic values of the above eight different dual-energy derived sequences for pancreatic cancer. The pancreatic parenchyma-tumor CT value difference, ratio of tumor to pancreatic parenchyma, and pancreatic parenchyma-tumor contrast to noise ratio were significantly different among eight sequences (P<0.05) . Mono-energetic 60kev image showed the largest parenchyma-tumor CT value [ (77.53 ± 23.42) HU] , and iodine map showed the lowest tumor/parenchyma enhancement ratio (0.39?0.12) and the largest contrast to noise ratio (4.08 ± 1.46) . Multiple sequences can be derived from dual-energy scan mode with DSCT via multiple post-processing methods. Integration of these sequences may further improve the sensitivity of the multislice spiral CT in the diagnosis of pancreatic cancer.

Factors affecting the lung perfused blood volume in patients with intrapulmonary clots after anti-coagulation therapy

Energy Technology Data Exchange (ETDEWEB)

Okada, Munemasa, E-mail: radokada@yamaguchi-u.ac.jp [Department of Radiology, Yamaguchi University Graduate School of Medicine 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Masuda, Yu [4th Grade of 6-year Medicine Doctor Program, Department of Medicine, Yamaguchi University Faculty of Medicine and Health Sciences 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Nakashima, Yoshiteru [Department of Radiology, Yamaguchi Grand Medical Center, Oosaki 77, Hofu, Yamaguchi 747-8511 (Japan); Nomura, Takafumi; Nakao, Sei [Department of Radiology, Yamaguchi University Graduate School of Medicine 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Suga, Kazuyoshi [Department of Radiology, St Hills Hospital, Imamurakita 3-7-18, Ube, Yamaguchi 755-0155 (Japan); Kido, Shoji [Computer-aided Diagnosis and Biomedical Imaging Research Biomedical Engineering, Applied Medical Engineering Science Graduate School of Medicine, Yamaguchi University, Tokiwadai 2-16-1, Ube, Yamaguchi 755-8611 (Japan); Matsunaga, Naofumi [Department of Radiology, Yamaguchi University Graduate School of Medicine 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan)

2015-08-15

Highlights: • Dual-energy CT can provide morphological and functional lung images in the same examination. • The subsequent dual-energy CT demonstrates the increased whole lung perfused blood volume (V{sub 120}) despite the residual intrapulmonary clots after treatment in one examination. • The increased whole lung perfusion (V{sub 120}) and a decreased low perfusion volume (V{sub 5}) result in the improvement in the low perfusion rate (%V{sub 5}) in the patients with acute pulmonary embolism after treatment. - Abstract: Objectives: Factors affecting the improvement in the lung perfused blood volume (LPBV) were evaluated based on the presence of intrapulmonary clots (IPCs) after anti-coagulation therapy using 64-slice dual-energy CT. Materials and methods: 96 patients exhibiting venous thromboembolism underwent initial and repeated LPBV examinations between December 2008 and July 2014. Fifteen patients were excluded due to pulmonary comorbidities, and a total of 81 patients were included in this study. Acute pulmonary embolism (PE) was diagnosed in 46 of the patients (56.7%). LPBV images were three-dimensionally reconstructed with two threshold ranges: 1–120 HU (V{sub 120}) and 1–5 HU (V{sub 5}), and the relative value of V{sub 5} per V{sub 120} expressed as %V{sub 5}. These values were subsequently compared with indicators of the severity of PE, such as the D-dimer level, heart rate and CT measurements. This study was approved by the local ethics committee. Results: In patients with IPCs, the D-dimer, V{sub 5} and %V{sub 5}values were significantly larger (p ≤ 0.01) in the initial LPBV, although these differences disappeared in subsequent LPBV after treatment. The right ventricular (RV) diameter, RV/left ventricular (RV/LV) diameter ratio and %V{sub 5} values were also significantly reduced, whereas the V{sub 5} value did not significantly decrease (p = 0.07), but V{sub 120} value significantly increased (p < 0.001) after treatment. However, in

On Various R-duals and the Duality Principle

DEFF Research Database (Denmark)

Stoeva, Diana T.; Christensen, Ole

2016-01-01

to a characterization of frames in terms of associated Riesz sequences; however, it is still an open question whether this abstract theory is a generalization of the duality principle. In this paper we prove that a modified version of the R-duals leads to a generalization of the duality principle that keeps all......The duality principle states that a Gabor system is a frame if and only if the corresponding adjoint Gabor system is a Riesz sequence. In general Hilbert spaces and without the assumption of any particular structure, Casazza, Kutyniok and Lammers have introduced the so-called R-duals that also lead...... the attractive properties of the R-duals. In order to provide extra insight into the relations between a given sequence and its R-duals, we characterize all the types of R-duals that are available in the literature for the special case where the underlying sequence is a Riesz basis....

A fast spectrum dual path flow cermet reactor

International Nuclear Information System (INIS)

Anghaie, S.; Feller, G.J.; Peery, S.D.; Parsley, R.C.

1993-01-01

A cermet fueled, dual path fast reactor for space nuclear propulsion applications is conceptually designed. The reactor utilizes an outer annulus core and an inner cylindrical core with radial and axial reflector. The dual path flow minimizes the impact of power peaking near the radial reflector. Basic neutronics and core design aspects of the reactor are discussed. The dual path reactor is integrated into a 25000 lbf thrust nuclear rocket

Development of design technology for dual-cooled fuel

International Nuclear Information System (INIS)

Kim, Hyung Kyu; Yoon, Kyung Ho; Lee, Young Ho

2010-03-01

Primary purpose of the project is to complete a basic design of the power uprating dual-cooled fuel's structural components for an actual use in the existing nuclear power plants. It also includes a basic design of the components of a dual-cooled fuel rod. To this end, during the three years of the first stage (2007.03.∼2010.02.), concepts and technical issues of the structural components such as a supporting structure, guide thimbles and instrumentation tube and the top and bottom end pieces were derived in order to comply with the functional requirements and design criteria of them. Basic design was carried out to resolve the issues by using analytical methods as well as experiments, and observed finally is that a structural compatibility of the designed dual-cooled fuel to the Korean Standard Nuclear Power Plant (OPR-1000). As for the dual-cooled fuel rod's components such as a plenum spring, a spacer and end plugs, a concept of them was established by using the basic dimension and array produced by other sub-projects. In turn, the basic design was completed by using the finite element analysis and conventional mechanical design formulae. Additionally, a welding method and equipment for a dual-cooled fuel rod specimen was also successfully developed to prepare for the irradiation tests at the HANARO. It was shown that a dual-cooed fuel for the OPR-1000 can be designed after manufacturing the partial assembly with the designed components and their drawings. The first stage was completed with passing the Gate checks proposed at the beginning. During the second stage(2010.03.∼2012.02.), researches on the mechanical behavior and structural integrity of the designed dual-cooled fuel will be conducted for preparing a license of it, which should be done when the dual-cooled fuel is commercialized

Isolation and Characterization of an Amylase Producing Yeast and its Application in Carotenoid Production Using Dual Culture

Directory of Open Access Journals (Sweden)

Iraj Nahvi

2005-06-01

Full Text Available Starch is a plant polysaccharide with unique applications in Iran. Its increasing production and processing recently have led to large volumes of industrial effluent as an environmental pollutant. In this study, an amylase producing yeast is isolated and identified as “Cryptococcus aerius” to investigate some of its characteristics such as its amylase secretion and starch digesting patterns, kinetics of amylase complex, and its capability for carotenoid production in dual culture. The results indicate that C.aerius is capable of soluble and raw maize starch digestion and assimilation. Raw starch digestion is scarce among yeast species; hence, it is industrially important. C.aerius digests soluble starch in the first 10 hours of cultivation and on the basis of amylase secreting patterns, it is therefore categorized with fast growing species on starch as carbon source. Non-pathogenicity, digestion of raw starch, heat stability of the secreted amylases complex (>55˚C, and the optimum pH level of 5.5- 6 for amylases complex are the set of properties that make this species capable of use in microbial production on an industrial scale. Absorption of carotenoid extract obtained from dual fermentation of C.aerius and Rhodotorula sp. indicates that the quality of carotenoids produced in dual fermentation is the same as that produced from pure Rhodotorula sp culture.

The dual description of long-distance QCD (Dual QCD)

International Nuclear Information System (INIS)

Baker, M.

1990-01-01

We construct and solve a local field theory which describes in terms of dual variables a system having an A μ propagator behaving like M 2 /q 4 in the infrared and discuss how this theory can be used as a starting point for describing long-distance QCD. 3 refs

Effect of engine load and biogas flow rate to the performance of a compression ignition engine run in dual-fuel (dieselbiogas) mode

Science.gov (United States)

Ambarita, H.

2018-02-01

The Government of Indonesia (GoI) has released a target on reduction Green Houses Gases emissions (GHG) by 26% from level business-as-usual by 2020, and the target can be up to 41% by international supports. In the energy sector, this target can be reached effectively by promoting fossil fuel replacement or blending with biofuel. One of the potential solutions is operating compression ignition (CI) engine in dual-fuel (diesel-biogas) mode. In this study effects of engine load and biogas flow rate on the performance and exhaust gas emissions of a compression ignition engine run in dual-fuel mode are investigated. In the present study, the used biogas is refined with methane content 70% of volume. The objectives are to explore the optimum operating condition of the CI engine run in dual-fuel mode. The experiments are performed on a four-strokes CI engine with rated output power of 4.41 kW. The engine is tested at constant speed 1500 rpm. The engine load varied from 600W to 1500W and biogas flow rate varied from 0 L/min to 6 L/min. The results show brake thermal efficiency of the engine run in dual-fuel mode is better than pure diesel mode if the biogas flow rates are 2 L/min and 4 L/min. It is recommended to operate the present engine in a dual-fuel mode with biogas flow rate of 4 L/min. The consumption of diesel fuel can be replaced up to 50%.

Accuracy of iodine quantification using dual energy CT in latest generation dual source and dual layer CT

NARCIS (Netherlands)

Pelgrim, Gert Jan; van Hamersvelt, Robbert W; Willemink, Martin J; Schmidt, Bernhard T; Flohr, Thomas; Schilham, Arnold; Milles, Julien; Oudkerk, Matthijs; Leiner, Tim; Vliegenthart, Rozemarijn

OBJECTIVE: To determine the accuracy of iodine quantification with dual energy computed tomography (DECT) in two high-end CT systems with different spectral imaging techniques. METHODS: Five tubes with different iodine concentrations (0, 5, 10, 15, 20 mg/ml) were analysed in an anthropomorphic

Quantitative dual energy CT measurements in rabbit VX2 liver tumors: Comparison to perfusion CT measurements and histopathological findings

International Nuclear Information System (INIS)

Zhang, Long Jiang; Wu, Shengyong; Wang, Mei; Lu, Li; Chen, Bo; Jin, Lixin; Wang, Jiandong; Larson, Andrew C.; Lu, Guang Ming

2012-01-01

Purpose: To evaluate the correlation between quantitative dual energy CT and perfusion CT measurements in rabbit VX2 liver tumors. Materials and methods: This study was approved by the institutional animal care and use committee at our institution. Nine rabbits with VX2 liver tumors underwent contrast-enhanced dual energy CT and perfusion CT. CT attenuation for the tumors and normal liver parenchyma and tumor-to-liver ratio were obtained at the 140 kVp, 80 kVp, average weighted images and dual energy CT iodine maps. Quantitative parameters for the viable tumor and adjacent liver were measured with perfusion CT. The correlation between the enhancement values of the tumor in iodine maps and perfusion CT parameters of each tumor was analyzed. Radiation dose from dual energy CT and perfusion CT was measured. Results: Enhancement values for the tumor were higher than that for normal liver parenchyma at the hepatic arterial phase (P < 0.05). The highest tumor-to-liver ratio was obtained in hepatic arterial phase iodine map. Hepatic blood flow of the tumor was higher than that for adjacent liver (P < 0.05). Enhancement values of hepatic tumors in the iodine maps positively correlated with permeability of capillary vessel surface (r = 0.913, P < 0.001), hepatic blood flow (r = 0.512, P = 0.010), and hepatic blood volume (r = 0.464, P = 0.022) at the hepatic arterial phases. The effective radiation dose from perfusion CT was higher than that from DECT (P < 0.001). Conclusions: The enhancement values for viable tumor tissues measured in iodine maps were well correlated to perfusion CT measurements in rabbit VX2 liver tumors. Compared with perfusion CT, dual energy CT of the liver required a lower radiation dose.

Numerical investigation of variable inlet guide vanes with trailing-edge dual slots to decrease the aerodynamic load on centrifugal compressor impeller

Directory of Open Access Journals (Sweden)

Jianchi Xin

2016-03-01

Full Text Available In engineering practice, most centrifugal compressors use variable inlet guide vanes which can provide pre-whirl and control volume flow rates. As the impeller of a centrifugal compressor passes through the wakes created from the guide vanes, the aerodynamic parameters change significantly. The concept of adding dual slots at the trailing-edge of the guide vanes is proposed for reducing the aerodynamic load on the compressor impeller blades. In this article, the steady and unsteady performances of the new guide vanes are analysed under two compressor operating conditions (winter and design conditions. The results show that the average amplitude of the impeller passing frequency at the leading edge has a 13% decrease under the winter condition, especially at the middle and root parts. Moreover, the dual slots structure has no effect on the overall compressor performance.

A Dual Processing Approach to Stereotype Change.

Science.gov (United States)

Johnston, Lucy; Coolen, Petra

1995-01-01

Considered stereotype change within a framework of dual process models. Using three experiments, manipulated task involvement, source credibility, and message quality. Findings proved dual process as appropriate when considering the processing of stereotype-disconfirming information and processing's impact on existing stereotypes. Different…

Targeting carbonic anhydrase IX by nitroimidazole based sulfamides enhances the therapeutic effect of tumor irradiation: A new concept of dual targeting drugs

International Nuclear Information System (INIS)

Dubois, Ludwig; Peeters, Sarah G.J.A.; Kuijk, Simon J.A. van; Yaromina, Ala; Lieuwes, Natasja G.; Saraya, Ruchi; Biemans, Rianne; Rami, Marouan; Parvathaneni, Nanda Kumar; Vullo, Daniela; Vooijs, Marc; Supuran, Claudiu T.; Winum, Jean-Yves

2013-01-01

Background and purpose: Carbonic anhydrase IX (CAIX) plays an important role in pH regulation processes critical for tumor cell growth and metastasis. We hypothesize that a dual targeting bioreductive nitroimidazole based anti-CAIX sulfamide drug (DH348) will reduce tumor growth and sensitize tumors to irradiation in a CAIX dependent manner. Material and methods: The effect of the dual targeting anti-CAIX (DH348) and its single targeting control drugs on extracellular acidification and radiosensitivity was examined in HT-29 colorectal carcinoma cells. Tumor growth and time to reach 4× start volume (T4×SV) was monitored for animals receiving DH348 (10 mg/kg) combined with tumor single dose irradiation (10 Gy). Results: In vitro, DH348 reduced hypoxia-induced extracellular acidosis, but did not change hypoxic radiosensitivity. In vivo, DH348 monotherapy decreased tumor growth rate and sensitized tumors to radiation (enhancement ratio 1.50) without systemic toxicity only for CAIX expressing tumors. Conclusions: A newly designed nitroimidazole and sulfamide dual targeting drug reduces hypoxic extracellular acidification, slows down tumor growth at nontoxic doses and sensitizes tumors to irradiation all in a CAIX dependent manner, suggesting no “off-target” effects. Our data therefore indicate the potential utility of a dual drug approach as a new strategy for tumor-specific targeting

Dual practice in the health sector: review of the evidence

Directory of Open Access Journals (Sweden)

Hipólito Fátima

2004-10-01

Full Text Available Abstract This paper reports on income generation practices among civil servants in the health sector, with a particular emphasis on dual practice. It first approaches the subject of public–private overlap. Thereafter it focuses on coping strategies in general and then on dual practice in particular. To compensate for unrealistically low salaries, health workers rely on individual coping strategies. Many clinicians combine salaried, public-sector clinical work with a fee-for-service private clientele. This dual practice is often a means by which health workers try to meet their survival needs, reflecting the inability of health ministries to ensure adequate salaries and working conditions. Dual practice may be considered present in most countries, if not all. Nevertheless, there is surprisingly little hard evidence about the extent to which health workers resort to dual practice, about the balance of economic and other motives for doing so, or about the consequences for the proper use of the scarce public resources dedicated to health. In this paper dual practice is approached from six different perspectives: (1 conceptual, regarding what is meant by dual practice; (2 descriptive, trying to develop a typology of dual practices; (3 quantitative, trying to determine its prevalence; (4 impact on personal income, the health care system and health status; (5 qualitative, looking at the reasons why practitioners so frequently remain in public practice while also working in the private sector and at contextual, personal life, institutional and professional factors that make it easier or more difficult to have dual practices; and (6 possible interventions to deal with dual practice.

Hermitian self-dual quasi-abelian codes

Directory of Open Access Journals (Sweden)

Herbert S. Palines

2017-12-01

Full Text Available Quasi-abelian codes constitute an important class of linear codes containing theoretically and practically interesting codes such as quasi-cyclic codes, abelian codes, and cyclic codes. In particular, the sub-class consisting of 1-generator quasi-abelian codes contains large families of good codes. Based on the well-known decomposition of quasi-abelian codes, the characterization and enumeration of Hermitian self-dual quasi-abelian codes are given. In the case of 1-generator quasi-abelian codes, we offer necessary and sufficient conditions for such codes to be Hermitian self-dual and give a formula for the number of these codes. In the case where the underlying groups are some $p$-groups, the actual number of resulting Hermitian self-dual quasi-abelian codes are determined.

Dual simulation of the massless lattice Schwinger model with topological term and non-zero chemical potential

Science.gov (United States)

Göschl, Daniel

2018-03-01

We discuss simulation strategies for the massless lattice Schwinger model with a topological term and finite chemical potential. The simulation is done in a dual representation where the complex action problem is solved and the partition function is a sum over fermion loops, fermion dimers and plaquette-occupation numbers. We explore strategies to update the fermion loops coupled to the gauge degrees of freedom and check our results with conventional simulations (without topological term and at zero chemical potential), as well as with exact summation on small volumes. Some physical implications of the results are discussed.

Control the Morphologies and the Pore Architectures of Meso porous Silicas through a Dual-Templating Approach

International Nuclear Information System (INIS)

Wang, H.; Chen, H.; Xu, Z.; Wang, S.; Li, B.; Li, Y.

2012-01-01

Meso porous silica nanospheres were prepared using a chiral cationic low-molecular-weight amphiphile and organic solvents such as toluene, cyclohexane, and tetrachlorocarbon through a dual-templating approach. X-ray diffraction, nitrogen sorption, field emission scanning electron microscopy, and transmission electron microscopy techniques have been used to characterize the meso porous silicas. The volume ratio of toluene to water plays an important role in controlling the morphologies and the pore architectures of the meso porous silicas. It was also found that meso porous silica nano flakes can be prepared by adding tetrahydrofuran to the reaction mixtures.

Human Factors Engineering: Current and Emerging Dual-Use Applications

Science.gov (United States)

Chandlee, G. O.; Goldsberry, B. S.

1994-01-01

Human Factors Engineering is a multidisciplinary endeavor in which information pertaining to human characteristics is used in the development of systems and machines. Six representatives considered to be experts from the public and private sectors were surveyed in an effort to identify the potential dual-use of human factors technology. Each individual was asked to provide a rating as to the dual-use of 85 identified NASA technologies. Results of the survey were as follows: nearly 75 percent of the technologies were identified at least once as high dual-use by one of the six survey respondents, and nearly 25 percent of the identified NASA technologies were identified as high dual-use technologies by a majority of the respondents. The perceived level of dual-use appeared to be independent of the technology category. Successful identification of dual-use technology requires expanded input from industry. As an adjunct, cost-benefit analysis should be conducted to identify the feasibility of the dual-use technology. Concurrent with this effort should be an examination of precedents established by other technologies in other industrial settings. Advances in human factors and systems engineering are critical to reduce risk in any workplace and to enhance industrial competitiveness.

Kaehler-Dirac ghosts for self-dual fields

International Nuclear Information System (INIS)

Labastida, J.M.F.; Pernici, M.

1988-01-01

We present the generalization to spacetime dimension D=4n+2 of the Lorentz covariant quadratic lagrangian for pairs of (anti)self-dual fields previously obtained by the authors in D=2. In the process of BRST quantizing this lagrangian a first-order quadratic lagrangian for ghost (anti)self-dual fields is found which, after gauge fixing, can be written in terms of bispinors and it turns out to be a Kaehler-Dirac lagrangian. The coupling to gravity is straightforward and the gravitational anomaly due to (anti)self-dual fields is obtained directly from an action principle. (orig.)

Dual of big bang and big crunch

International Nuclear Information System (INIS)

Bak, Dongsu

2007-01-01

Starting from the Janus solution and its gauge theory dual, we obtain the dual gauge theory description of the cosmological solution by the procedure of double analytic continuation. The coupling is driven either to zero or to infinity at the big-bang and big-crunch singularities, which are shown to be related by the S-duality symmetry. In the dual Yang-Mills theory description, these are nonsingular as the coupling goes to zero in the N=4 super Yang-Mills theory. The cosmological singularities simply signal the failure of the supergravity description of the full type IIB superstring theory

Dual-layer ultrathin film optics: I. Theory and analysis

International Nuclear Information System (INIS)

Wang, Qian; Lim, Kim Peng

2015-01-01

This paper revisits dual-layer ultrathin film optics, which can be used for functional graded refractive index thin film stack. We present the detailed derivation including s-polarized and p-polarized light under arbitrary incidence angle showing the equivalence between the dual-layer ultrathin films and a negative birefringent thin film and also the approximations made during the derivation. Analysis of the approximations shows the influence of thickness of dual-layer thin films, the incidence angle and desired refractive index of the birefringent film. Numerical comparison between the titanium dioxide/aluminum oxide based dual-layer ultrathin film stack and the equivalent birefringent film verifies the theoretical analysis. The detailed theoretical study and numerical comparison provide a physical insight and design guidelines for dual-layer ultrathin film based optical devices. (paper)

Gas Flows in Dual Active Galactic Nuclei

Science.gov (United States)

Mueller Sanchez, Francisco; Comerford, Julia M.; Davies, Richard; Treister, Ezequiel; Privon, George C.; Nevin, Becky

2018-06-01

Dual Active Galactic Nuclei (AGN) are the Rosetta stone to understand the role of galaxy mergers in triggering nuclear activity and regulating black hole (BH) and galaxy growth. But very little is known about the physical processes required to effectively trigger AGN activity and regulate the growth of the two BHs. The work I will present here characterizes for the first time the properties of the stars, gas (molecular, ionized, and highly-ionized) and dust in all the confirmed dual AGN at z prototypical merger system NGC 6240: vigorous star formation, two AGNs, outflowing winds of ionized gas, rippling dust and gas lanes, and tidal tails. In this galaxy, we observe for the first time a dual outflow of different species of gas: an AGN-driven outflow of highly-ionized gas to the northeast and a starburst-driven outflow of ionized hydrogen to the northwest. This shows that stellar feedback and supermassive black hole feedback can work in tandem to regulate the stellar growth of a galaxy after a merger event. These results open a new door to studies of dual AGN and AGN pairs in general, and enable dual AGN to be used, for the first time, for studies of galaxy evolution.

CARDIOVASCULAR ENDOCRINOLOGY Dual RAAS blockade has dual effects on outcome

NARCIS (Netherlands)

Heerspink, Hiddo J. Lambers; de Zeeuw, Dick

Makani and colleagues report that dual blockade of the renin-angiotensin-aldosterone system is associated with harm despite previous studies showing that this approach decreases blood pressure and albuminuria. Do these results imply that we should abandon surrogate markers? Or should we become more

Virtual non-contrast CT using dual energy spectral CT: Feasibility of coronary artery calcium scoring

International Nuclear Information System (INIS)

Song, In Young; Yi, Jeong Geun; Park, Jeong Hee; Lee, Sung Mok; Lee, Kyung Soo; Chung, Myung Jin

2016-01-01

To evaluate the feasibility of coronary artery calcium scoring based on three virtual noncontrast-enhanced (VNC) images derived from single-source spectral dual-energy CT (DECT) as compared with true noncontrast-enhanced (TNC) images. This prospective study was conducted with the approval of our Institutional Review Board. Ninety-seven patients underwent noncontrast CT followed by contrast-enhanced chest CT using single-source spectral DECT. Iodine eliminated VNC images were reconstructed using two kinds of 2-material decomposition algorithms (material density iodine-water pair [MDW], material density iodine-calcium pair [MDC]) and a material suppressed algorithm (material suppressed iodine [MSI]). Two readers independently quantified calcium on VNC and TNC images. The Spearman correlation coefficient test and Bland-Altman method were used for statistical analyses. Coronary artery calcium scores from all three VNC images showed excellent correlation with those from the TNC images (Spearman's correlation coefficient [ρ] = 0.94, 0.88, and 0.89 for MDW, MDC, and MSI, respectively; p < 0.001 for all pairs). Measured coronary calcium volumes from VNC images also correlated well with those from TNC images (ρ = 0.92, 0.87, and 0.91 for MDW, MDC, and MSI, respectively; p < 0.001 for all pairs). Among the three VNC images, coronary calcium from MDW correlated best with that from TNC. The coronary artery calcium scores and volumes were significantly lower from the VNC images than from the TNC images (p < 0.001 for all pairs). The use of VNC images from contrast-enhanced CT using dual-energy material decomposition/suppression is feasible for coronary calcium scoring. The absolute value from VNC tends to be smaller than that from TNC

Virtual non-contrast CT using dual energy spectral CT: Feasibility of coronary artery calcium scoring

Energy Technology Data Exchange (ETDEWEB)

Song, In Young; Yi, Jeong Geun; Park, Jeong Hee [Dept. of Radiology, Konkuk University School of Medicine, Seoul (Korea, Republic of); Lee, Sung Mok; Lee, Kyung Soo; Chung, Myung Jin [Dept. of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2016-06-15

To evaluate the feasibility of coronary artery calcium scoring based on three virtual noncontrast-enhanced (VNC) images derived from single-source spectral dual-energy CT (DECT) as compared with true noncontrast-enhanced (TNC) images. This prospective study was conducted with the approval of our Institutional Review Board. Ninety-seven patients underwent noncontrast CT followed by contrast-enhanced chest CT using single-source spectral DECT. Iodine eliminated VNC images were reconstructed using two kinds of 2-material decomposition algorithms (material density iodine-water pair [MDW], material density iodine-calcium pair [MDC]) and a material suppressed algorithm (material suppressed iodine [MSI]). Two readers independently quantified calcium on VNC and TNC images. The Spearman correlation coefficient test and Bland-Altman method were used for statistical analyses. Coronary artery calcium scores from all three VNC images showed excellent correlation with those from the TNC images (Spearman's correlation coefficient [ρ] = 0.94, 0.88, and 0.89 for MDW, MDC, and MSI, respectively; p < 0.001 for all pairs). Measured coronary calcium volumes from VNC images also correlated well with those from TNC images (ρ = 0.92, 0.87, and 0.91 for MDW, MDC, and MSI, respectively; p < 0.001 for all pairs). Among the three VNC images, coronary calcium from MDW correlated best with that from TNC. The coronary artery calcium scores and volumes were significantly lower from the VNC images than from the TNC images (p < 0.001 for all pairs). The use of VNC images from contrast-enhanced CT using dual-energy material decomposition/suppression is feasible for coronary calcium scoring. The absolute value from VNC tends to be smaller than that from TNC.

Numerical Simulation of a Dual-Chamber Oscillating Water Column Wave Energy Converter

Directory of Open Access Journals (Sweden)

Dezhi Ning

2017-09-01

Full Text Available The performance of a dual-chamber Oscillating Water Column (OWC Wave Energy Converter (WEC is considered in the present study. The device has two sub-chambers with a shared orifice. A two-dimensional (2D fully nonlinear numerical wave flume based on the potential-flow theory and the time-domain higher-order boundary element method (HOBEM is applied for the simulation. The incident waves are generated by using the immerged sources and the air-fluid coupling influence is considered with a simplified pneumatic model. In the present study, the variation of the surface elevation and the water column volume in the two sub-chambers are investigated. The effects of the chamber geometry (i.e., the draft and breadth of two chambers on the surface elevation and the air pressure in the chamber are investigated, respectively. It is demonstrated that the surface elevations in the two sub-chambers are strongly dependent on the wave conditions. The larger the wavelength, the more synchronous motion of the two water columns in the two sub-chambers, thus, the lager the variation of the water column volume.

Value of dual-time-point 18FDG PET-CT imaging on involved-field radiotherapy for hilar and mediastinal metastatic lymph nodes in non-small cell lung cancer

International Nuclear Information System (INIS)

Hu Man; Sun Xindong; Liu Ningbo; Gong Heyi; Fu Zheng; Ma Li; Li Xinke; Xu Xiaoqing; Yu Jinming

2008-01-01

Objective: To discuss the value of dual-time-point 18 FDG PET-CT imaging on involved-field radiotherapy for hilar and mediastinal metastatic lymph nodes in patients with non-small cell lung cancer (NSCLC). Methods: Fifty-four patients with NSCLC were included in this analysis, including 34 men and 20 women with mean age of 59 (34-76) years. Two sequential PET-CT scans given 3-5 days before surgery were standard single-time-point imaging for the whole body and delayed imaging for the thorax. The pathologic data were used as golden standard to determine the difference between the standard single-time-point and dual-time-point PET-CT imaging in the definition of gross target volume (GTV) of involved-field radiotherapy for metastatic lymph nodes. Results: For hilar metastatic lymph nodes, the GTV defined by single-time-point imaging was consistent with pathologic GTV in 21 patients (39%), comparing with 31 patients (57%) by dual-time-point imaging. Using pathologic data as golden standard, GTV alteration defined by single-time-point imaging had statistically significant difference comparing with that defined by dual-time-point imaging( =519.00, P=0.023). For mediastinal metastatic lymph nodes, the GTV defined by single-time-point imaging was consistent with pathologic GTV in 30 patients (56%), comparing with 36 patients (67%) by dual-time-point imaging. Using pathologic data as golden standard, GTV alteration defined by single-time-point imaging had no statistically significant difference comparing with that defined by dual-time-point imaging (u= 397.50, P=0.616). Conclusions: For patients with NSCLC receiving involved-field radiotherapy, GTV definition for hilar and mediastinal metastatic lymph nodes by dual-time-point imaging is more consistent with that by pathologic data. Dual-time-point imaging has a larger value in terms of target delineation for hilar and mediastinal metastatic lymph nodes. (authors)

[LONG-TERM SURVIVAL OF DUAL DISORDERS PATIENTS AFTER MIXED CARE IN DUAL DISORDERS AND STANDARD WARDS VERSUS CARE ONLY IN DUAL DISORDERS WARD].

Science.gov (United States)

Gimelfarb, Yuri; Wolf, Aviva; Ben-Tzarfati, Mashit

2017-01-01

Dual disorders (co-occurring mental illness and substance abuse disorders in the same person) are extremely common among patients receiving mental health services. Integrated treatment has been proposed as the standard of care and it describes a flexible combination of treatments from the mental health and addiction fields that are blended together in the therapy. Scientific evidence for survival of dual disorders patients (DDPs), who had integrated dual disorders inpatient care, is lacking. To determine the long term survival rates following integrated care (Integrated Dual Diagnosis Treatment Ward [IDDTW] only) versus mixed care (IDDTW and psychiatric wards) during the life-time of DDPs. The charts of 333 subjects admitted to IDDTW during the period January 2002 - June 2006 were assessed at least 8 years after the first admission. Psychiatric diagnoses have been established and grouped according to international classification of diseases and health-related problems -10th edition (ICD-10). The Kaplan-Meier survival analysis was used to estimate the cumulative survival rates in all the subpopulations, and the predictive values of different variables were assessed by Cox proportional-hazards regression model. The total all-cause 12-year, unadjusted mortality was 21.1% in integrated care versus 24.6% in mixed care (pintegrated care as a predictive factor for all-cause mortality. The findings showed that there was no consistent evidence to support integrated inpatient care over mixed care, as measured by long-term survival. More studies are required in order to address the challenges posed in the treatment of DDPs.

Separation of nucleation and growth of voids during tensile deformation of a dual phase steel using synchrotron microtomography

Energy Technology Data Exchange (ETDEWEB)

Requena, Guillermo, E-mail: guillermo.requena@tuwien.ac.at [INSA-Lyon, MATEIS CNRS UMR5510, F-69621 Villeurbanne (France); Maire, Eric; Leguen, Claire [INSA-Lyon, MATEIS CNRS UMR5510, F-69621 Villeurbanne (France); Thuillier, Sandrine [LIMATB, Université de Bretagne-Sud, rue de Saint Maudé, BP 92116, 56321 Lorient Cedex (France)

2014-01-01

The damage evolution in a DP980 dual phase steel is followed in situ by synchrotron microtomography during tensile deformation focusing on the effect that the triaxiality, induced by different sample geometries, exerts on damage formation and damage evolution. The growth of existing voids is separated from the voids nucleated between consecutive deformation steps using three-dimensional image analysis. The experimental results are correlated with those obtained by finite element analysis using a Gurson–Tvergaard–Needleman framework with a Chu and Needleman formulation to introduce the effect of nucleation of cavities. A relatively simple way to determine the nucleation parameters is proposed based on the volume of nucleated voids obtained from the tomographies. The evolution of the total volume fraction of cavities obtained from the calculations shows a good agreement with the experiments for the notched samples and reflects the effect of triaxiality on damage. Contrarily to experiments, the calculated accumulated volume fraction of nucleated voids does not reflect the effect of triaxiality suggesting the necessity to implement this parameter in the nucleation model.

Comparison of dual photon and dual energy X-ray bone densitometers in a clinic setting

International Nuclear Information System (INIS)

Nelson, D.A.; Shaffer, S.; Brown, E.B.; Flynn, M.J.; Cody, D.D.

1991-01-01

Two separate studies were conducted. We evaluated the relationships between results of lumbar spine measurements using two dual photon absorptiometry (DPA1 and DPA2) instruments and one dual energy X-ray (DXA) instrument with the same subject (49 volunteers), and also in 65 patients who were measured on the DPA1 and DXA machines. Second, we measured the lumbar spine and the proximal femur in three groups of 12 female volunteers three times on one instrument within 1 week. We purposely simulated a busy clinic setting with different technologists, older radioactive sources, and a heterogeneous patient group. The comparison study indicated a significant difference between the mean bone density values reported by the machines, but the results were highly correlated (R 2 = 0.89-0.96). This study emphasizes the differences between instruments, the potential for greater error in busy clinic environments, and the apparent superiority of dual energy X-ray absorptiometry under these less than ideal conditions. (orig./GDG)

The discharge behavior of lithium-ion batteries using the Dual-Potential Multi-Scale Multi-Dimensional (MSMD) Battery Model

DEFF Research Database (Denmark)

Saeed Madani, Seyed; Swierczynski, Maciej Jozef; Kær, Søren Knudsen

2017-01-01

This paper gives insight into the discharge behavior of lithium-ion batteries based on the investigations, which have been done by the researchers [1– 19]. In this article, the battery's discharge behaviour at various discharge rates is studied and surface monitor, discharge curve, volume monitor...... to analysis the discharge behaviour of lithium-ion batteries. The results show that surface monitor plot of discharge curve at 1 C has a decreasing trend and volume monitor plot of maximum temperature in the domain has slightly increasing pattern over the simulation time. For the curves of discharge...... plot of maximum temperature in the domain and maximum temperature in the area are illustrated. Additionally, an external and internal short-circuit treatment for three cases have been studied. The Dual-Potential Multi-Scale Multi-Dimensional (MSMD) Battery Model (BM) was used by ANSYS FLUENT software...

Dual-Resonant Implantable Circular Patch Antenna for Biotelemetry Communication

Directory of Open Access Journals (Sweden)

Rongqiang Li

2016-01-01

Full Text Available A compact broadband implantable circular patch antenna is designed and experimentally demonstrated for Medical Implant Communications Service (MICS band (402–405 MHz. Compared with other similar implantable antennas, the proposed antenna incorporates three advantages for biotelemetry communication. First, it can realize a broad impedance bandwidth by exhibiting dual resonances. Second, it can obtain a compact structure by introducing two arc-shaped slots, a rectangular slot and a circular slot on metal radiating patch. Finally, it can display a friendly shape by using a circular structure. The proposed antenna occupies a volume of about 431.5 mm3 (10.42 × 1.27π mm3, which is a compromise between miniaturization and bandwidth. The measured −10 dB impedance bandwidth is 55 MHz (385–440 MHz. Furthermore, the radiation performance and human body safety consideration of the antenna are examined and characterized.

Diagnosis of dual human immunodeficiency virus types 1 & 2 ...

African Journals Online (AJOL)

Background: The presence of dual HlV-l/HIV-2 infection in Ghana and the different drug requirements for the treatment of HlV-1 and HIV-2 presents difficulties for the treatment of dual infections with both viruses. Objectives: To determine the prevalence of the dual sero-positive profile in treatment naive patients at a principal ...

Perceptual Space of Superimposed Dual-Frequency Vibrations in the Hands.

Science.gov (United States)

Hwang, Inwook; Seo, Jeongil; Choi, Seungmoon

2017-01-01

The use of distinguishable complex vibrations that have multiple spectral components can improve the transfer of information by vibrotactile interfaces. We investigated the qualitative characteristics of dual-frequency vibrations as the simplest complex vibrations compared to single-frequency vibrations. Two psychophysical experiments were conducted to elucidate the perceptual characteristics of these vibrations by measuring the perceptual distances among single-frequency and dual-frequency vibrations. The perceptual distances of dual-frequency vibrations between their two frequency components along their relative intensity ratio were measured in Experiment I. The estimated perceptual spaces for three frequency conditions showed non-linear perceptual differences between the dual-frequency and single-frequency vibrations. A perceptual space was estimated from the measured perceptual distances among ten dual-frequency compositions and five single-frequency vibrations in Experiment II. The effect of the component frequency and the frequency ratio was revealed in the perceptual space. In a percept of dual-frequency vibration, the lower frequency component showed a dominant effect. Additionally, the perceptual difference among single-frequency and dual-frequency vibrations were increased with a low relative difference between two frequencies of a dual-frequency vibration. These results are expected to provide a fundamental understanding about the perception of complex vibrations to enrich the transfer of information using vibrotactile stimuli.

Comparative performance analysis of a dual-solenoid mechanical oscillator

International Nuclear Information System (INIS)

Lee, V C C; Lee, H V; Harno, H G; Woo, K C

2015-01-01

An innovative dual-solenoid electro-mechanical-vibro-impact system has been constructed and experimentally studied. Comparative studies against a mechanical spring system and a permanent magnet system have been performed, where it is shown that the dual-solenoid system is able to produce oscillations better than the permanent magnet system and more energy efficiently. Comparison with a higher-powered dual solenoid system has also been conducted where a stationary solenoid has shown to be a more dominant parameter. In addition, it is also discovered that a mechanical oscillator in the dual-solenoid system is independent of the angular frequency. (paper)

Dual symmetry in Born-Infeld theory

International Nuclear Information System (INIS)

Khademi, S; Ayoubi, A

2008-01-01

Born-Infeld theory is a non-linear formalism which has many applications in string and electromagnetic theories. Although, the existence of magnetic monopoles and dyons are suggested by Born-Infeld theory, but this theory is not invariant under the dual transformations. In this theory electric fields for point charged particles are not singular at origin (r = 0), but magnetic fields and vector potentials are still singular. In this paper we show that the vanishing of dual symmetry is responsible for these singularities. Furthermore, we present the dual symmetric Born-Infeld theory, by a symmetric definition of electromagnetic fields in terms of new scalar and vector potentials, as well as the ordinary ones. All singularities of vector potential and magnetic field are removed as an immediate consequence of this symmetry.

A dual approach to IS strategy

DEFF Research Database (Denmark)

Ivang, Reimer

2014-01-01

This paper discusses IS strategising and how the combination of the planning and the incremental approaches can enable successful IS strategising. IS strategising is conceptualised as a dual organisational process in which the network and the hierarchy positively coexist through group-learning pr......This paper discusses IS strategising and how the combination of the planning and the incremental approaches can enable successful IS strategising. IS strategising is conceptualised as a dual organisational process in which the network and the hierarchy positively coexist through group......-learning processes. The findings from two case studies illustrate the theoretical framework. An analysis of 28 interviews reveal the complexity of IS strategising and show that IS strategising is best understood as a dual dynamic-interactive processing which the choice of strategic approach is not a dichotomy...

Attenuation-based kV pair selection in dual source dual energy computed tomography angiography of the chest: impact on radiation dose and image quality

Energy Technology Data Exchange (ETDEWEB)

Renapurkar, Rahul D.; Azok, Joseph; Lempel, Jason; Karim, Wadih; Graham, Ruffin [Thoracic Imaging, L10, Imaging Institute, Cleveland Clinic, Cleveland, OH (United States); Primak, Andrew [Siemens Medical Solutions, Malvern, PA (United States); Tandon, Yasmeen [Case Western Reserve University-Metro Health Medical Center, Department of Radiology, Cleveland, OH (United States); Bullen, Jennifer [Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH (United States); Dong, Frank [Section of Medical Physics, Cleveland Clinic, Cleveland, OH (United States)

2017-08-15

The purpose of this study was to evaluate the impact of attenuation-based kilovoltage (kV) pair selection in dual source dual energy (DSDE)-pulmonary embolism (PE) protocol examinations on radiation dose savings and image quality. A prospective study was carried out on 118 patients with suspected PE. In patients in whom attenuation-based kV pair selection selected the 80/140Sn kV pair, the pre-scan 100/140Sn CTDIvol (computed tomography dose index volume) values were compared with the pre-scan 80/140Sn CTDIvol values. Subjective and objective image quality parameters were assessed. Attenuation-based kV pair selection switched to the 80/140Sn kV pair (''switched'' cohort) in 63 out of 118 patients (53%). The mean 100/140Sn pre-scan CTDIvol was 8.8 mGy, while the mean 80/140Sn pre-scan CTDIvol was 7.5 mGy. The average estimated dose reduction for the ''switched'' cohort was 1.3 mGy (95% CI 1.2, 1.4; p < 0.001), representing a 15% reduction in dose. After adjusting for patient weight, mean attenuation was significantly higher in the ''switched'' vs. ''non-switched'' cohorts in all five pulmonary arteries and in all lobes on iodine maps. This study demonstrates that attenuation-based kV pair selection in DSDE examination is feasible and can offer radiation dose reduction without compromising image quality. (orig.)

Accuracy of iodine quantification using dual energy CT in latest generation dual source and dual layer CT

Energy Technology Data Exchange (ETDEWEB)

Pelgrim, Gert Jan; Oudkerk, Matthijs [University of Groningen, University Medical Center Groningen, Center for Medical Imaging - North East Netherlands, P.O. Box EB44, Groningen (Netherlands); Hamersvelt, Robbert W. van; Willemink, Martin J.; Schilham, Arnold; Leiner, Tim [Utrecht University Medical Center, Department of Radiology, Utrecht (Netherlands); Schmidt, Bernhard T.; Flohr, Thomas [Siemens Healthcare GmbH, Forchheim (Germany); Milles, Julien [Philips Healthcare, Best (Netherlands); Vliegenthart, Rozemarijn [University of Groningen, University Medical Center Groningen, Center for Medical Imaging - North East Netherlands, P.O. Box EB44, Groningen (Netherlands); University of Groningen, University Medical Center Groningen, Department of Radiology, Groningen (Netherlands)

2017-09-15

To determine the accuracy of iodine quantification with dual energy computed tomography (DECT) in two high-end CT systems with different spectral imaging techniques. Five tubes with different iodine concentrations (0, 5, 10, 15, 20 mg/ml) were analysed in an anthropomorphic thoracic phantom. Adding two phantom rings simulated increased patient size. For third-generation dual source CT (DSCT), tube voltage combinations of 150Sn and 70, 80, 90, 100 kVp were analysed. For dual layer CT (DLCT), 120 and 140 kVp were used. Scans were repeated three times. Median normalized values and interquartile ranges (IQRs) were calculated for all kVp settings and phantom sizes. Correlation between measured and known iodine concentrations was excellent for both systems (R = 0.999-1.000, p < 0.0001). For DSCT, median measurement errors ranged from -0.5% (IQR -2.0, 2.0%) at 150Sn/70 kVp and -2.3% (IQR -4.0, -0.1%) at 150Sn/80 kVp to -4.0% (IQR -6.0, -2.8%) at 150Sn/90 kVp. For DLCT, median measurement errors ranged from -3.3% (IQR -4.9, -1.5%) at 140 kVp to -4.6% (IQR -6.0, -3.6%) at 120 kVp. Larger phantom sizes increased variability of iodine measurements (p < 0.05). Iodine concentration can be accurately quantified with state-of-the-art DECT systems from two vendors. The lowest absolute errors were found for DSCT using the 150Sn/70 kVp or 150Sn/80 kVp combinations, which was slightly more accurate than 140 kVp in DLCT. (orig.)

Linking the dual system with higher education in Denmark

DEFF Research Database (Denmark)

Jørgensen, Christian Helms

2013-01-01

As more than half of every new generation of youth enter higher education in Den-mark the strength of the dual system of vocational education is becoming its weakness. Completing a programme in the dual system doesn’t give access to higher ed-ucation, and the system is increasingly seen as a ‘blind...... alley’. This weakness is closely related to the strengths of the dual system. The dual system is successful in giving direct and fast access to employment for the students, and this contributes to a very low rate of youth unemployment in Denmark. Students who complete a programme in the dual system......, become well integrated into the labour market, but at the same time they are diverted from higher education. This has lately put the question of hybrid qualifications on the agenda in Denmark....

Health care utilization among Medicare-Medicaid dual eligibles: a count data analysis

Directory of Open Access Journals (Sweden)

Shin Jaeun

2006-04-01

Full Text Available Abstract Background Medicare-Medicaid dual eligibles are the beneficiaries of both Medicare and Medicaid. Dual eligibles satisfy the eligibility conditions for Medicare benefit. Dual eligibles also qualify for Medicaid because they are aged, blind, or disabled and meet the income and asset requirements for receiving Supplement Security Income (SSI assistance. The objective of this study is to explore the relationship between dual eligibility and health care utilization among Medicare beneficiaries. Methods The household component of the nationally representative Medical Expenditure Panel Survey (MEPS 1996–2000 is used for the analysis. Total 8,262 Medicare beneficiaries are selected from the MEPS data. The Medicare beneficiary sample includes individuals who are covered by Medicare and do not have private health insurance during a given year. Zero-inflated negative binomial (ZINB regression model is used to analyse the count data regarding health care utilization: office-based physician visits, hospital inpatient nights, agency-sponsored home health provider days, and total dental visits. Results Dual eligibility is positively correlated with the likelihood of using hospital inpatient care and agency-sponsored home health services and the frequency of agency-sponsored home health days. Frequency of dental visits is inversely associated with dual eligibility. With respect to racial differences, dually eligible Afro-Americans use more office-based physician and dental services than white duals. Asian duals use more home health services than white duals at the 5% statistical significance level. The dual eligibility programs seem particularly beneficial to Afro-American duals. Conclusion Dual eligibility has varied impact on health care utilization across service types. More utilization of home healthcare among dual eligibles appears to be the result of delayed realization of their unmet healthcare needs under the traditional Medicare-only program

Dual Numbers Approach in Multiaxis Machines Error Modeling

Directory of Open Access Journals (Sweden)

Jaroslav Hrdina

2014-01-01

Full Text Available Multiaxis machines error modeling is set in the context of modern differential geometry and linear algebra. We apply special classes of matrices over dual numbers and propose a generalization of such concept by means of general Weil algebras. We show that the classification of the geometric errors follows directly from the algebraic properties of the matrices over dual numbers and thus the calculus over the dual numbers is the proper tool for the methodology of multiaxis machines error modeling.

Assessment of pancreatic adenocarcinoma: use of low-dose whole pancreatic CT perfusion and individualized dual-energy CT scanning

International Nuclear Information System (INIS)

Li, Hai-ou; Guo, Jun; Li, Xiao; Qi, Yao-dong; Wang, Xi-ming; Xu, Zhuo-dong; Liu, Cheng; Chen, Jiu-hong

2015-01-01

The objective of this study was to investigate the value of low-dose whole pancreatic computed tomography (CT) perfusion integrated with individualized dual-energy CT (DECT) scanning in the diagnosis of pancreatic adenocarcinoma. Twenty patients with pancreatic adenocarcinoma underwent pancreatic CT perfusion as well as individualized dual-phase DECT pancreatic scans. Perfusion characteristics of non-tumourous pancreatic parenchyma and pancreatic adenocarcinoma were analysed. Weighted-average 120 kVp images and the optimal monoenergetic images in dual phase were reconstructed and the contrast noise ratio (CNR) of pancreas-to-tumour were compared. There were significant difference on blood flow as well as blood volume between pancreatic adenocarcinoma and the non-tumourous pancreatic parenchyma (P < 0.05), whereas no difference on permeability (P > 0.05). CNRs of pancreas-to-tumour in individualized pancreatic phase were significantly higher than those in venous phase (P < 0.05), and CNRs of optimal monoenergetic images were higher than those on weighted-average 120 kVp images (P < 0.05) in both phase. Total effective radiation dose of CT examination was around 9.32–13.75 mSv. Low-dose whole pancreatic CT perfusion can provide functional information, and the individualized pancreatic phase DECT scan is the optimal method for detecting pancreatic adenocarcinomas. The integration of the two techniques has great value in clinical application.

On Goldstone particles and the Adler principle in dual models

International Nuclear Information System (INIS)

Volkov, D.V.; Zheltukhin, A.A.; Pashnev, A.I.

1975-01-01

The results that have been obtained on the basis of considering the spontaneous vacuum transitions for the cases of Veneziano dual model and dual M-model are generalized to model containing internal quantum numbers of SU(N)-group. This generalization allows to consider how in dual models the spontaneous violation of symmetry occurs, which Goldstone particles appear in this process, how Adler's principle is realized for dual amplitudes and their topics related of spontaneous violation of symmetry

46 CFR 183.324 - Dual voltage generators.

Science.gov (United States)

2010-10-01

... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS... neutral of a dual voltage system must be solidly connected at the switchboard's neutral bus; and (2) The neutral bus shall be connected to ground. (b) The neutral of a dual voltage system must be accessible for...

Truncated Dual-Cap Nucleation Site Development

Science.gov (United States)

Matson, Douglas M.; Sander, Paul J.

2012-01-01

During heterogeneous nucleation within a metastable mushy-zone, several geometries for nucleation site development must be considered. Traditional spherical dual cap and crevice models are compared to a truncated dual cap to determine the activation energy and critical cluster growth kinetics in ternary Fe-Cr-Ni steel alloys. Results of activation energy results indicate that nucleation is more probable at grain boundaries within the solid than at the solid-liquid interface.

Identifying HIV-1 dual infections

Directory of Open Access Journals (Sweden)

Cornelissen Marion

2007-09-01

Full Text Available Abstract Transmission of human immunodeficiency virus (HIV is no exception to the phenomenon that a second, productive infection with another strain of the same virus is feasible. Experiments with RNA viruses have suggested that both coinfections (simultaneous infection with two strains of a virus and superinfections (second infection after a specific immune response to the first infecting strain has developed can result in increased fitness of the viral population. Concerns about dual infections with HIV are increasing. First, the frequent detection of superinfections seems to indicate that it will be difficult to develop a prophylactic vaccine. Second, HIV-1 superinfections have been associated with accelerated disease progression, although this is not true for all persons. In fact, superinfections have even been detected in persons controlling their HIV infections without antiretroviral therapy. Third, dual infections can give rise to recombinant viruses, which are increasingly found in the HIV-1 epidemic. Recombinants could have increased fitness over the parental strains, as in vitro models suggest, and could exhibit increased pathogenicity. Multiple drug resistant (MDR strains could recombine to produce a pan-resistant, transmittable virus. We will describe in this review what is presently known about super- and re-infection among ambient viral infections, as well as the first cases of HIV-1 superinfection, including HIV-1 triple infections. The clinical implications, the impact of the immune system, and the effect of anti-retroviral therapy will be covered, as will as the timing of HIV superinfection. The methods used to detect HIV-1 dual infections will be discussed in detail. To increase the likelihood of detecting a dual HIV-1 infection, pre-selection of patients can be done by serotyping, heteroduplex mobility assays (HMA, counting the degenerate base codes in the HIV-1 genotyping sequence, or surveying unexpected increases in the

Dual-target cost in visual search for multiple unfamiliar faces.

Science.gov (United States)

Mestry, Natalie; Menneer, Tamaryn; Cave, Kyle R; Godwin, Hayward J; Donnelly, Nick

2017-08-01

The efficiency of visual search for one (single-target) and either of two (dual-target) unfamiliar faces was explored to understand the manifestations of capacity and guidance limitations in face search. The visual similarity of distractor faces to target faces was manipulated using morphing (Experiments 1 and 2) and multidimensional scaling (Experiment 3). A dual-target cost was found in all experiments, evidenced by slower and less accurate search in dual- than single-target conditions. The dual-target cost was unequal across the targets, with performance being maintained on one target and reduced on the other, which we label "preferred" and "non-preferred" respectively. We calculated the capacity for each target face and show reduced capacity for representing the non-preferred target face. However, results show that the capacity for the non-preferred target can be increased when the dual-target condition is conducted after participants complete the single-target conditions. Analyses of eye movements revealed evidence for weak guidance of fixations in single-target search, and when searching for the preferred target in dual-target search. Overall, the experiments show dual-target search for faces is capacity- and guidance-limited, leading to superior search for 1 face over the other in dual-target search. However, learning faces individually may improve capacity with the second face. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The neural architecture of age-related dual-task interferences

Directory of Open Access Journals (Sweden)

Witold Xaver Chmielewski

2014-07-01

Full Text Available In daily life elderly adults exhibit deficits when dual-tasking is involved. So far these deficits have been verified on a behavioral level in dual-tasking. Yet, the neuronal architecture of these deficits in aging still remains to be explored especially when late-middle aged individuals around 60 years of age are concerned. Neuroimaging studies in young participants concerning dual-tasking were, among others, related to activity in middle frontal (MFG and superior frontal gyrus (SFG and the anterior insula (AI. According to the frontal lobe hypothesis of aging, alterations in these frontal regions (i.e., SFG and MFG might be responsible for cognitive deficits. We measured brain activity using fMRI, while examining age-dependent variations in dual-tasking by utilizing the PRP (psychological refractory period test. Behavioral data showed an increasing PRP effect in late-middle aged adults. The results suggest the age-related deteriorated performance in dual-tasking, especially in conditions of risen complexity. These effects are related to changes in networks involving the anterior insula, the SFG and the MFG. The results suggest that different cognitive subprocesses are affected that mediate the observed dual-tasking problems in late-middle aged individuals.

The neural architecture of age-related dual-task interferences.

Science.gov (United States)

Chmielewski, Witold X; Yildiz, Ali; Beste, Christian

2014-01-01

In daily life elderly adults exhibit deficits when dual-tasking is involved. So far these deficits have been verified on a behavioral level in dual-tasking. Yet, the neuronal architecture of these deficits in aging still remains to be explored especially when late-middle aged individuals around 60 years of age are concerned. Neuroimaging studies in young participants concerning dual-tasking were, among others, related to activity in middle frontal (MFG) and superior frontal gyrus (SFG) and the anterior insula (AI). According to the frontal lobe hypothesis of aging, alterations in these frontal regions (i.e., SFG and MFG) might be responsible for cognitive deficits. We measured brain activity using fMRI, while examining age-dependent variations in dual-tasking by utilizing the PRP (psychological refractory period) test. Behavioral data showed an increasing PRP effect in late-middle aged adults. The results suggest the age-related deteriorated performance in dual-tasking, especially in conditions of risen complexity. These effects are related to changes in networks involving the AI, the SFG and the MFG. The results suggest that different cognitive subprocesses are affected that mediate the observed dual-tasking problems in late-middle aged individuals.

N = 1 dual string pairs and their modular superpotentials

International Nuclear Information System (INIS)

Luest, D.

1998-01-01

We review the duality between heterotic and F-theory string vacua with N=1 space-time supersymmetry in eight, six and four dimensions. In particular, we discuss two chains of four-dimensional F-theory/heterotic dual string pairs, where F-theory is compactified on certain elliptic Calabi-Yau fourfolds, and the dual heterotic vacua are given by compactifications on elliptic Calabi-Yau threefolds plus the specification of the E 8 x E 8 gauge bundles. We show that the massless spectra of the dual pairs agree by using, for one chain of models, an index formula to count the heterotic bundle moduli and determine the dual F-theory spectra from the Hodge numbers of the fourfolds and of the type IIB base spaces. Moreover as a further check, we demonstrate that for one particular heterotic/F-theory dual pair the N=1 superpotentials are the same. (orig.)

Block copolymer/homopolymer dual-layer hollow fiber membranes

KAUST Repository

Hilke, Roland; Neelakanda, Pradeep; Behzad, Ali Reza; Nunes, Suzana Pereira; Peinemann, Klaus-Viktor

2014-01-01

We manufactured the first time block copolymer dual-layer hollow fiber membranes and dual layer flat sheet membranes manufactured by double solution casting and phase inversion in water. The support porous layer was based on polystyrene

Study on dual plant concept for the next generation boiling water reactors

International Nuclear Information System (INIS)

Sato, Takashi; Oikawa, Hirohide

1999-01-01

The paper presents the study results on the basic concept of dual BWRs. For the convenience, we call the concept here as Trial Study on BWR dual concept (TSBWR dual). The concept is general and applicable to all BWRs which have internal recirculation pumps (RIP). The TSBWR dual is a plant concept of dual BWRs contained in a same secondary containment building. The plant output is from 2 x l,350 MWe up to 2 x 1,700 MWe. This concept is mainly aiming at safety improvement and cost savings of the next generation BWRs. The TSBWR dual has two RPVs and two dry wells (DW). It has, however, only one wet well (WW) and only one R/B. The WW and the R/B are shared by the dual reactors. The operating floor is also shared by the two reactors. The TSBWR dual has both passive safety systems and active safety systems. They are also shared between the two reactors. A lot of sharing between the dual reactors enables significant cost savings accompanied by the power increase up to 3,400 MWe. Although the TSBWR dual consists of two reactors, the simplified cylindrical configuration of the key structures and reduction of the R/B height can minimize the plant construction period. The TSBWR dual provides a concept with which we can challenge to construct a dual BWR plant in the near future. (author)

Effect of microstructure on the elasto-viscoplastic deformation of dual phase titanium structures

Science.gov (United States)

Ozturk, Tugce; Rollett, Anthony D.

2018-02-01

The present study is devoted to the creation of a process-structure-property database for dual phase titanium alloys, through a synthetic microstructure generation method and a mesh-free fast Fourier transform based micromechanical model that operates on a discretized image of the microstructure. A sensitivity analysis is performed as a precursor to determine the statistically representative volume element size for creating 3D synthetic microstructures based on additively manufactured Ti-6Al-4V characteristics, which are further modified to expand the database for features of interest, e.g., lath thickness. Sets of titanium hardening parameters are extracted from literature, and The relative effect of the chosen microstructural features is quantified through comparisons of average and local field distributions.

Dual AAV Vectors for Stargardt Disease.

Science.gov (United States)

Trapani, Ivana

2018-01-01

Stargardt disease (STGD1), due to mutations in the large ABCA4 gene, is the most common inherited macular degeneration in humans. Attempts at developing gene therapy approaches for treatment of STGD1 are currently ongoing. Among all the vectors available for gene therapy of inherited retinal diseases, those based on adeno-associated viruses (AAV) are the most promising given the efficacy shown in various animal models and their excellent safety profile in humans, as confirmed in many ongoing clinical trials. However, one of the main obstacles for the use of AAV is their limited effective packaging capacity of about 5 kb. Taking advantage of the AAV genome's ability to concatemerize , others and we have recently developed dual AAV vectors to overcome this limit. We tested dual AAV vectors for ABCA4 delivery, and found that they transduce efficiently both mouse and pig photoreceptors , and rescue the Abca4-/- mouse retinal phenotype, indicating their potential for gene therapy of STGD1. This chapter details how we designed dual AAV vectors for the delivery of the ABCA4 gene and describes the techniques that can be explored to evaluate dual AAV transduction efficiency in vitro and in the retina, and their efficacy in the mouse model of STGD1.

Coherent cavity-enhanced dual-comb spectroscopy.

Science.gov (United States)

Fleisher, Adam J; Long, David A; Reed, Zachary D; Hodges, Joseph T; Plusquellic, David F

2016-05-16

Dual-comb spectroscopy allows for the rapid, multiplexed acquisition of high-resolution spectra without the need for moving parts or low-resolution dispersive optics. This method of broadband spectroscopy is most often accomplished via tight phase locking of two mode-locked lasers or via sophisticated signal processing algorithms, and therefore, long integration times of phase coherent signals are difficult to achieve. Here we demonstrate an alternative approach to dual-comb spectroscopy using two phase modulator combs originating from a single continuous-wave laser capable of > 2 hours of coherent real-time averaging. The dual combs were generated by driving the phase modulators with step-recovery diodes where each comb consisted of > 250 teeth with 203 MHz spacing and spanned > 50 GHz region in the near-infrared. The step-recovery diodes are passive devices that provide low-phase-noise harmonics for efficient coupling into an enhancement cavity at picowatt optical powers. With this approach, we demonstrate the sensitivity to simultaneously monitor ambient levels of CO2, CO, HDO, and H2O in a single spectral region at a maximum acquisition rate of 150 kHz. Robust, compact, low-cost and widely tunable dual-comb systems could enable a network of distributed multiplexed optical sensors.

A Dual-Continuum Model for Brine Migration in Salt Associated with Heat-Generating Nuclear Waste: Fully Coupled Thermal-Hydro-Mechanical Analysis

Science.gov (United States)

Hu, M.; Rutqvist, J.

2017-12-01

The disposal of heat-generating nuclear waste in salt host rock establishes a thermal gradient around the waste package that may cause brine inclusions in the salt grains to migrate toward the waste package. In this study, a dual-continuum model is developed to analyze such a phenomenon. This model is based on the Finite Volume Method (FVM), and it is fully thermal-hydro-mechanical (THM) coupled. For fluid flow, the dual-continuum model considers flow in the interconnected pore space and also in the salt grains. The mass balance of salt and water in these two continua is separately established, and their coupling is represented by flux associated with brine migration. Together with energy balance, such a system produces a coupled TH model with strongly nonlinear features. For mechanical analysis, a new formulation is developed based on the Voronoi tessellated mesh. By relating each cell to several connected triangles, first-order approximation is constructed. The coupling between thermal and mechanical fields is only considered in terms of thermal expansion. And the coupling between the hydraulic and mechanical fields in terms of pore-volume effects is consistent with Biot's theory. Therefore, a fully coupled THM model is developed. Several demonstration examples are provided to verify the model. Last the new model is applied to analyze coupled THM behavior and the results are compared with experimental data.

New MDS or near MDS self-dual codes over finite fields

OpenAIRE

Tong, Hongxi; Wang, Xiaoqing

2016-01-01

The study of MDS self-dual codes has attracted lots of attention in recent years. There are many papers on determining existence of $q-$ary MDS self-dual codes for various lengths. There are not existence of $q-$ary MDS self-dual codes of some lengths, even these lengths $< q$. We generalize MDS Euclidean self-dual codes to near MDS Euclidean self-dual codes and near MDS isodual codes. And we obtain many new near MDS isodual codes from extended negacyclic duadic codes and we obtain many new M...

Characterization of Oblique Dual Frame Pairs

DEFF Research Database (Denmark)

Christensen, Ole; Eldar, Yonina

2006-01-01

Given a frame for a subspace W of a Hilbert space H, we consider all possible families of oblique dual frame vectors on an appropriately chosen subspace V. In place of the standard description, which involves computing the pseudoinverse of the frame operator, we develop an alternative characteriz...... for the case of shift-invariant spaces with a single generator. The theory is also adapted to the standard frame setting in which the original and dual frames are defined on the same space. Copyright (C) 2006 Hindawi Publishing Corporation. All rights reserved.......Given a frame for a subspace W of a Hilbert space H, we consider all possible families of oblique dual frame vectors on an appropriately chosen subspace V. In place of the standard description, which involves computing the pseudoinverse of the frame operator, we develop an alternative...

Production performance laws of vertical wells by volume fracturing in CBM reservoirs

Directory of Open Access Journals (Sweden)

Liehui Zhang

2017-05-01

Full Text Available Volume fracturing technology has been widely applied in the development of coalbed methane (CBM reservoirs. As for the stimulated reservoir volume (SRV created by volume fracturing, the seepage laws of fluids are described more accurately and rationally in the rectangular composite model than in the traditional radial composite model. However, the rectangular composite model considering SRV cannot be solved using the analytical or semi-analytical function method, and its solution from the linear flow model has larger errors. In view of this, SRV areas of CBM reservoirs were described by means of dual-medium model in this paper. The complex CBM migration mechanisms were investigated comprehensively, including adsorption, desorption, diffusion and seepage. A well testing model for rectangular composite fracturing wells in CBM reservoirs based on unsteady-state diffusion was built and solved using the boundary element method combined with Laplace transformation, Stehfest numerical inversion and computer programming technology. Thus, production performance laws of CBM reservoirs were clarified. The flow regimes of typical well testing curves were divided and the effects on change laws of production performance from the boundary size of gas reservoirs, permeability of volume fractured areas, adsorption gas content, reservoir permeability and SRV size were analyzed. Eventually, CBM reservoirs after the volume fracturing stimulation were described more accurately and rationally. This study provides a theoretical basis for a better understanding of the CBM migration laws and an approach to evaluating and developing CBM reservoirs efficiently and rationally.

Formation of Offset and Dual Active Galactic Nuclei

Science.gov (United States)

Barrows, Scott; Comerford, Julia M.; Greene, Jenny E.

2018-06-01

Galaxy mergers are effective mechanisms for triggering accretion onto supermassive black holes (SMBHs) and thereby powering active galactic nuclei (AGN). In the merger scenario, when the SMBH from only one galaxy is accreting we observe a spatially offset AGN, and when the SMBHs from both galaxies are accreting we observe a dual AGN. Understanding the merger conditions that lead to the formation of offset AGN versus dual AGN is fundamental to informing models of hierarchical SMBH growth and the physics leading to the accretion of matter onto SMBHs. However, while the role of galaxy mergers for AGN triggering has been well-studied, the efficiency with which these events trigger offset AGN versus dual AGN is currently unclear. One reason for this gap in knowledge can be attributed to the observational difficulties in distinguishing between offset and dual AGN since doing so requires high spatial resolution, especially in the small separation regime where merger-driven AGN triggering is most likely to occur. To overcome this hurdle, we have utilized the spatial resolution of the Chandra X-ray Observatory to develop a unique sample of AGN hosted by late-stage galaxy mergers. Moreover, we have recently acquired Hubble Space Telescope imaging for a subset of these systems to examine the role that their merger morphologies play in SMBH growth and the formation of offset and dual AGN. We find that offset AGN are predominately found in minor mergers, whereas dual AGN are usually hosted by major mergers and galaxies with large morphological asymmetries. Furthermore, in both offset and dual AGN, the rate of SMBH growth increases toward more major mergers and larger morphological asymmetries. These results are in agreement with numerical simulations predicting that merger morphology is a relevant parameter governing SMBH merger-driven growth, and these results are the first to observationally confirm these trends at small pair separations.

Coherent cavity-enhanced dual-comb spectroscopy

OpenAIRE

Fleisher, Adam J.; Long, David A.; Reed, Zachary D.; Hodges, Joseph T.; Plusquellic, David F.

2016-01-01

Dual-comb spectroscopy allows for the rapid, multiplexed acquisition of high-resolution spectra without the need for moving parts or low-resolution dispersive optics. This method of broadband spectroscopy is most often accomplished via tight phase locking of two mode-locked lasers or via sophisticated signal processing algorithms, and therefore, long integration times of phase coherent signals are difficult to achieve. Here we demonstrate an alternative approach to dual-comb spectroscopy usin...

Adolescents and Dual Diagnosis in a Psychiatric Emergency Service.

Science.gov (United States)

Matali, José Luis; Andión, Oscar; Pardo, Marta; Iniesta, Raquel; Serrano, Eduard; San, Luis

2016-03-02

In recent years, both the prevalence of drug use and related child and adolescent psychiatric emergencies have risen sharply. There are few studies about the impact on child and adolescent emergency services. This study has a twofold aim. The first is to describe the prevalence of substance use disorders, mental disorders and dual diagnosis (substance use problems plus mental disorder) in adolescents in psychiatric emergency service. The second is to analyze clinical and healthcare differences between patients with dual diagnosis and patients with a mental disorder without substance use disorder.We retrospectively reviewed 4012 discharge forms for emergencies treated at the psychiatric emergency department during the period 2007-2009. We obtained a sample of 1795 visits. This sample was divided into two groups: the dual diagnosis group (n = 477) and the psychiatric disorder group (n = 1318).The dual diagnosis group accounted for 26.5% of psychiatric emergencies analyzed. Compared to the psychiatric disorder group,the dual diagnosis group had significantly more conduct disorders, social problems, involuntariness in the visit, less hospital admissions and less connection with the healthcare network.Adolescents with a dual diagnosis account for a high percentage of visits at child and adolescent psychiatric emergency services. This patient group requires specialized care both at emergency services and in specific units. Accordingly, these units should play a triple role when handling dual diagnosis: detection, brief treatment and referral to a specialised unit.

Dual fan, dual-duct system meets air quality, energy-efficiency needs

Energy Technology Data Exchange (ETDEWEB)

Schuler, M. [Pageau Morel and Associates, Montreal, Quebec (Canada)

1996-03-01

Canada`s Space Centre in Saint-Hubert Quebec is a 300,000 ft{sup 2} (27,871 m{sup 2}) complex that houses the headquarters of the Canadian Space Agency, the Canadian Astronaut Training Centre, mission ground control installations, research facilities, offices and the required support facilities. A comfortable, pleasant research environment was a primary concern for the Space Centre, given its elite clientele. The objectives were high indoor-air quality, design flexibility, energy efficiency and low capital costs. Dual duct systems which are the heart of the mechanical concept allowed the designers to meet these objectives. The Space Centre`s offices, laboratories and conference center are all served by dual-duct systems. All operate using an air economizer cycle. Gas boilers provide them with hot water for heating and steam for humidification while centrifugal chillers provide chilled water for cooling. This article describes the design.

Dual-chamber/dual-anode proportional counter incorporating an intervening thin-foil solid neutron converter

International Nuclear Information System (INIS)

Boatner, Lynn A.; Neal, John S.; Blackston, Matthew A.; Kolopus, James A.; Ramey, Joanne O.

2012-01-01

A dual-chamber/dual-anode gas proportional counter utilizing thin solid 6 LiF or 10 B neutron converters coated on a 2-micon-thick Mylar film that is positioned between the two counter chambers and anodes has been designed, fabricated, and tested using a variety of fill gases—including naturally abundant helium. In this device, neutron conversion products emitted from both sides of the coated converter foil are detected—rather than having half of the products absorbed in the wall of a conventional tube-type counter where the solid neutron converter is deposited on the tube wall. Geant4-based radiation transport calculations were used to determine the optimum neutron converter coating thickness for both isotopes. Solution methods for applying these optimized-thickness coatings on a Mylar film were developed that were carried out at room temperature without any specialized equipment and that can be adapted to standard coating methods such as silk screen or ink jet printing. The performance characteristics of the dual-chamber/dual-anode neutron detector were determined for both types of isotopically enriched converters. The experimental performance of the 6 LiF-converter-based detector was described well by modeling results from Geant4. Additional modeling studies of multiple-foil/multiple-chamber/anode configurations addressed the basic issue of the relatively longer absorption range of neutrons versus the shorter range of the conversion products for 6 LiF and 10 B. Combined with the experimental results, these simulations indicate that a high-performance neutron detector can be realized in a single device through the application of these multiple-foil/solid converter, multiple-chamber detector concepts.

Dual photon excitation microscopy and image threshold segmentation in live cell imaging during compression testing.

Science.gov (United States)

Moo, Eng Kuan; Abusara, Ziad; Abu Osman, Noor Azuan; Pingguan-Murphy, Belinda; Herzog, Walter

2013-08-09

Morphological studies of live connective tissue cells are imperative to helping understand cellular responses to mechanical stimuli. However, photobleaching is a constant problem to accurate and reliable live cell fluorescent imaging, and various image thresholding methods have been adopted to account for photobleaching effects. Previous studies showed that dual photon excitation (DPE) techniques are superior over conventional one photon excitation (OPE) confocal techniques in minimizing photobleaching. In this study, we investigated the effects of photobleaching resulting from OPE and DPE on morphology of in situ articular cartilage chondrocytes across repeat laser exposures. Additionally, we compared the effectiveness of three commonly-used image thresholding methods in accounting for photobleaching effects, with and without tissue loading through compression. In general, photobleaching leads to an apparent volume reduction for subsequent image scans. Performing seven consecutive scans of chondrocytes in unloaded cartilage, we found that the apparent cell volume loss caused by DPE microscopy is much smaller than that observed using OPE microscopy. Applying scan-specific image thresholds did not prevent the photobleaching-induced volume loss, and volume reductions were non-uniform over the seven repeat scans. During cartilage loading through compression, cell fluorescence increased and, depending on the thresholding method used, led to different volume changes. Therefore, different conclusions on cell volume changes may be drawn during tissue compression, depending on the image thresholding methods used. In conclusion, our findings confirm that photobleaching directly affects cell morphology measurements, and that DPE causes less photobleaching artifacts than OPE for uncompressed cells. When cells are compressed during tissue loading, a complicated interplay between photobleaching effects and compression-induced fluorescence increase may lead to interpretations in

A novel dual-feed low-dropout regulator

International Nuclear Information System (INIS)

Duan Zhikui; Hu Jianguo; Ding Yi; Lu Chong; Ding Yanyu; Wang Deming; Tan Hongzhou

2015-01-01

A novel dual-feed (DF) low-dropout (LDO) is presented. The DF-LDO adopts dual control loops to maintain the output voltage. The dual control loops include a feedback loop and a feedforward loop. There is an equilibrium point in dual control loops, and the equilibrium point is the output voltage of the DF-LDO. In addition, the transient performance is optimized by adjusting the damping ratio and natural frequency. With a 1 μF decoupling capacitor, the proposed DF-LDO is fabricated in a 0.18 μm CMOS process and its output voltage is 1.5 V. When the workload changes from 100 μA to 100 mA in 100 ns, load regulation of 7 mV for a 100 mA step is achieved, the settling time is 997 ns and the undershoot is 12.8 mV; when the workload changes from 100 mA to 100 μA in 100 ns, the settling time is 249 ns with an imperceptible overshoot. (paper)

Longitudinal effects of bilingualism on dual-tasking.

Science.gov (United States)

Sörman, Daniel Eriksson; Josefsson, Maria; Marsh, John E; Hansson, Patrik; Ljungberg, Jessica K

2017-01-01

An ongoing debate surrounds whether bilinguals outperform monolinguals in tests of executive processing. The aim of this study was to investigate if there are long-term (10 year) bilingual advantages in executive processing, as indexed by dual-task performance, in a sample that were 40-65 years at baseline. The bilingual (n = 24) and monolingual (n = 24) participants were matched on age, sex, education, fluid intelligence, and study sample. Participants performed free-recall for a 12-item list in three dual-task settings wherein they sorted cards either during encoding, retrieval, or during both encoding and retrieval of the word-list. Free recall without card sorting was used as a reference to compute dual-task costs. The results showed that bilinguals significantly outperformed monolinguals when they performed card-sorting during both encoding and retrieval of the word-list, the condition that presumably placed the highest demands on executive functioning. However, dual-task costs increased over time for bilinguals relative to monolinguals, a finding that is possibly influenced by retirement age and limited use of second language in the bilingual group.

Universal Superspace Unitary Operator and Nilpotent (Anti-)Dual-BRST Symmetries: Superfield Formalism

International Nuclear Information System (INIS)

Malik, R. P.; Srinivas, N.; Bhanja, T.

2016-01-01

We exploit the key concepts of the augmented version of superfield approach to Becchi-Rouet-Stora-Tyutin (BRST) formalism to derive the superspace (SUSP) dual unitary operator and its Hermitian conjugate and demonstrate their utility in the derivation of the nilpotent and absolutely anticommuting (anti-)dual-BRST symmetry transformations for a set of interesting models of the Abelian 1-form gauge theories. These models are the one (0+1)-dimensional (1D) rigid rotor and modified versions of the two (1+1)-dimensional (2D) Proca as well as anomalous gauge theories and 2D model of a self-dual bosonic field theory. We show the universality of the SUSP dual unitary operator and its Hermitian conjugate in the cases of all the Abelian models under consideration. These SUSP dual unitary operators, besides maintaining the explicit group structure, provide the alternatives to the dual horizontality condition (DHC) and dual gauge invariant restrictions (DGIRs) of the superfield formalism. The derivations of the dual unitary operators and corresponding (anti-)dual-BRST symmetries are completely novel results in our present investigation.

Evaluation of HER2 gene amplification in invasive breast cancer using a dual-color chromogenic in situ hybridization (dual CISH).

Science.gov (United States)

Kato, Nobuaki; Itoh, Hitoshi; Serizawa, Akihiko; Hatanaka, Yutaka; Umemura, Shinobu; Osamura, R Yoshiyuki

2010-07-01

Fluorescence in situ hybridization (FISH) assay is considered the 'gold standard' for evaluation of HER2/neu (HER2) gene status, however, it is difficult to recognize morphologic features of tumors using fluorescence microscopy. Thus, chromogenic in situ hybridization (CISH) has been proposed as an alternative method to evaluate HER2 gene amplification. Here, we examined the dual color CISH (dual CISH) method which provides information regarding the copy number of the HER2 gene and chromosome 17 centromere from a single slide. We examined 40 cases of invasive ductal carcinomas of the breast that were resected surgically. HER2 gene status was assessed with FISH (Abbott) and dual CISH (Dako). HER2 gene amplification status was classified according to the guidelines of the American Society of Clinical Oncology and College of American Pathologists (ASCO/CAP). Comparison of the cut-off values for HER2/chromosome 17 centromere copy number ratio obtained by dual CISH and FISH showed that there was almost perfect agreement between two methods (Kappa coefficient 0.96). The results of the two commercial products were almost consistent for evaluation of HER2 gene counts on the sections. The current study proved that dual CISH is comparable with FISH for evaluating HER2 gene status.

Working Memory Training Improves Dual-Task Performance on Motor Tasks.

Science.gov (United States)

Kimura, Takehide; Kaneko, Fuminari; Nagahata, Keita; Shibata, Eriko; Aoki, Nobuhiro

2017-01-01

The authors investigated whether working memory training improves motor-motor dual-task performance consisted of upper and lower limb tasks. The upper limb task was a simple reaction task and the lower limb task was an isometric knee extension task. 45 participants (age = 21.8 ± 1.6 years) were classified into a working memory training group (WM-TRG), dual-task training group, or control group. The training duration was 2 weeks (15 min, 4 times/week). Our results indicated that working memory capacity increased significantly only in the WM-TRG. Dual-task performance improved in the WM-TRG and dual-task training group. Our study provides the novel insight that working memory training improves dual-task performance without specific training on the target motor task.

Preparation of YBa2Cu3O7-δ powders by the thermal decomposition of a heteronuclear complex, CuY1/3Ba2/3(dhbaen)(NO3)1/3(H2O)3

International Nuclear Information System (INIS)

Hasegawa, E.; Aono, H.; Sadaoka, Y.; Traversa, E.

1999-01-01

YBa 2 Cu 3 O 7-δ powders were prepared by the thermal decomposition of a heteronuclear complex, CuY 1/3 Ba 2/3 (dhbaen)(NO 3 ) 1/3 (H 2 O) 3 . The products of the complex thermal decomposition were analyzed by TG-DTA, XRD, SEM-Auger and XPS. The decomposition of the CuY 1/3 Ba 2/3 -complex was obtained at about 500 C and the product was a mixture of oxides and carbonates. The formation of YBa 2 Cu 3 O 7-δ proceeded at 800 C, with a gradual decomposition of the carbonates. A homogeneous distribution of each element, Y, Ba, and Cu, was observed for the decomposed CuY 1/3 Ba 2/3 -complex by SEM-Auger analysis. The binding energy values of Ba3d 5/2 and O1s photolines from Ba and O in the superconductive lattice did not shift during the sputtering period. Furthermore, the formation of Ba rich regions on the surface was depressed by using the complex as a starting material for homogeneous 123-oxide, YBa 2 Cu 3 O 7-δ . (orig.)

Charge distribution in an two-chain dual model

International Nuclear Information System (INIS)

Fialkowski, K.; Kotanski, A.

1983-01-01

Charge distributions in the multiple production processes are analysed using the dual chain model. A parametrisation of charge distributions for single dual chains based on the νp and anti vp data is proposed. The rapidity charge distributions are then calculated for pp and anti pp collisions and compared with the previous calculations based on the recursive cascade model of single chains. The results differ at the SPS collider energies and in the energy dependence of the net forward charge supplying the useful tests of the dual chain model. (orig.)

Dual roles and dual identities: enhancing the experience of in-service teacher training in English Further Education

Directory of Open Access Journals (Sweden)

Orr, Kevin

2009-06-01

Full Text Available In marked distinction from other sectors of education, around 90 percent of Further Education (FE staff in England are employed untrained and complete their Initial Teacher Training (ITT on a part-time in-service basis. By consequence, these staff sustain the dual role of employed teacher and teacher-trainee usually at the beginning of their career. This paper reports on a project funded by ESCalate which researched the dual roles and dual identities of employee and trainee on in-service FE teacher-training courses. It argues that the lack of a culture of pedagogical development in colleges along with the pressure for trainees to quickly cope with teaching can lead to conservative practice as expedience may be prioritised over flair. In response, the paper makes recommendations to enhance the experience and development of in-service teacher trainees.

Vortex dynamics in self-dual Chern-Simons-Higgs systems

International Nuclear Information System (INIS)

Kim, Y.; Lee, K.

1994-01-01

We consider vortex dynamics in self-dual Chern-Simons-Higgs systems. We show that the naive Aharonov-Bohm phase is the inverse of the statistical phase expected from the vortex spin, and that the self-dual configurations of vortices are degenerate in energy but not in angular momentum. We also use the path integral formalism to derive the dual formulation of Chern-Simons-Higgs systems in which vortices appear as charged particles. We argue that in addition to the electromagnetic interaction, there is an additional interaction between vortices, the so-called Magnus force, and that these forces can be put together into a single ''dual electromagnetic'' interaction. This dual electromagnetic interaction leads to the right statistical phase. We also derive and study the effective action for slowly moving vortices, which contains terms both linear and quadratic in the vortex velocity. We show that vortices can be bounded to each other by the Magnus force

Accuracy of Dual-Energy Virtual Monochromatic CT Numbers: Comparison between the Single-Source Projection-Based and Dual-Source Image-Based Methods.

Science.gov (United States)

Ueguchi, Takashi; Ogihara, Ryota; Yamada, Sachiko

2018-03-21

To investigate the accuracy of dual-energy virtual monochromatic computed tomography (CT) numbers obtained by two typical hardware and software implementations: the single-source projection-based method and the dual-source image-based method. A phantom with different tissue equivalent inserts was scanned with both single-source and dual-source scanners. A fast kVp-switching feature was used on the single-source scanner, whereas a tin filter was used on the dual-source scanner. Virtual monochromatic CT images of the phantom at energy levels of 60, 100, and 140 keV were obtained by both projection-based (on the single-source scanner) and image-based (on the dual-source scanner) methods. The accuracy of virtual monochromatic CT numbers for all inserts was assessed by comparing measured values to their corresponding true values. Linear regression analysis was performed to evaluate the dependency of measured CT numbers on tissue attenuation, method, and their interaction. Root mean square values of systematic error over all inserts at 60, 100, and 140 keV were approximately 53, 21, and 29 Hounsfield unit (HU) with the single-source projection-based method, and 46, 7, and 6 HU with the dual-source image-based method, respectively. Linear regression analysis revealed that the interaction between the attenuation and the method had a statistically significant effect on the measured CT numbers at 100 and 140 keV. There were attenuation-, method-, and energy level-dependent systematic errors in the measured virtual monochromatic CT numbers. CT number reproducibility was comparable between the two scanners, and CT numbers had better accuracy with the dual-source image-based method at 100 and 140 keV. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

DUAL TRAINING IN RUSSIA: FROM THE CONCEPT TO PRACTICE

Directory of Open Access Journals (Sweden)

Alexander A. Listvin

2016-01-01

Full Text Available The purpose of the present article is to judge and justify the conditions of system elements application of dual training at implementation of programs of professional education for increase of efficiency of functioning and quality of preparation of qualified personnel by institutions of the secondary professional education (SPE. Methods. The methods used in work involve the comparative analysis of practice of application of dual training in system of professional education of Germany and regions of Russia for the purpose of identification of the existing problems and definition of optimum organizational and legal and didactic conditions. Results. The essence of system of dual training, its strong and weaknesses reveals. Necessary and indispensable conditions of application of dual training in modern regional systems of professional education are proved. Scientific novelty. According to the author, modern publications on problems and ways of development of professional education in Russia contain enough antinomy of standard and legal and organizational and administrative character. In particular, operating by the concept «dual education», an identification of the practice-focused and dual training introduction «the list 50 of the most demanded in labor market, the new and perspective professions that demand secondary professional education» as opposed to the existing list of professions and the constitutional guarantee of public and free secondary professional education. Standard and legal, and didactic conditions of application of elements of dual training in regional systems of professional education are proved theoretically. Practical significance. Implementation of the research outcomes can be useful to pedagogical staff of institutions of secondary professional education, representatives of employers and Chambers of Commerce and Industry to the organization and use of system of dual training in training of skilled workers (serving

Dual completion method

Energy Technology Data Exchange (ETDEWEB)

Mamedov, N Ya; Kadymova, K S; Dzhafarov, Sh T

1963-10-28

One type of dual completion method utilizes a single tubing string. Through the use of the proper tubing equipment, the fluid from the low-productive upper formation is lifted by utilizing the surplus energy of a submerged pump, which handles the production from the lower stratum.

Modeling of the flame propagation in coal-dust- methane air mixture in an enclosed sphere volume

International Nuclear Information System (INIS)

Krainov, A Yu; Moiseeva, K M

2016-01-01

The results of the numerical simulation of the flame front propagation in coal-dust- methane-air mixture in an enclosed volume with the ignition source in the center of the volume are presented. The mathematical model is based on a dual-velocity two-phase model of the reacting gas-dispersion medium. The system of equations includes the mass-conversation equation, the impulse-conversation equation, the total energy-conversation equation of the gas and particles taking into account the thermal conductivity and chemical reactions in the gas and on the particle surface, mass-conversation equation of the mixture gas components considering the diffusion and the burn-out and the particle burn-out equation. The influence of the coal particle mass on the pressure in the volume after the mixture burn out and on the burn-out time has been investigated. It has been shown that the burning rate of the coal-dust methane air mixtures depends on the coal particle size. (paper)

On Dual Gabor Frame Pairs Generated by Polynomials

DEFF Research Database (Denmark)

Christensen, Ole; Rae Young, Kim

2010-01-01

We provide explicit constructions of particularly convenient dual pairs of Gabor frames. We prove that arbitrary polynomials restricted to sufficiently large intervals will generate Gabor frames, at least for small modulation parameters. Unfortunately, no similar function can generate a dual Gabo...

Pairs of dual periodic frames

DEFF Research Database (Denmark)

Christensen, Ole; Goh, Say Song

2012-01-01

The time–frequency analysis of a signal is often performed via a series expansion arising from well-localized building blocks. Typically, the building blocks are based on frames having either Gabor or wavelet structure. In order to calculate the coefficients in the series expansion, a dual frame...... is needed. The purpose of the present paper is to provide constructions of dual pairs of frames in the setting of the Hilbert space of periodic functions L2(0,2π). The frames constructed are given explicitly as trigonometric polynomials, which allows for an efficient calculation of the coefficients...

UWB dual burst transmit driver

Science.gov (United States)

Dallum, Gregory E [Livermore, CA; Pratt, Garth C [Discovery Bay, CA; Haugen, Peter C [Livermore, CA; Zumstein, James M [Livermore, CA; Vigars, Mark L [Livermore, CA; Romero, Carlos E [Livermore, CA

2012-04-17

A dual burst transmitter for ultra-wideband (UWB) communication systems generates a pair of precisely spaced RF bursts from a single trigger event. An input trigger pulse produces two oscillator trigger pulses, an initial pulse and a delayed pulse, in a dual trigger generator. The two oscillator trigger pulses drive a gated RF burst (power output) oscillator. A bias driver circuit gates the RF output oscillator on and off and sets the RF burst packet width. The bias driver also level shifts the drive signal to the level that is required for the RF output device.

Towards a big crunch dual

Energy Technology Data Exchange (ETDEWEB)

Hertog, Thomas E-mail: hertog@vulcan2.physics.ucsb.edu; Horowitz, Gary T

2004-07-01

We show there exist smooth asymptotically anti-de Sitter initial data which evolve to a big crunch singularity in a low energy supergravity limit of string theory. This opens up the possibility of using the dual conformal field theory to obtain a fully quantum description of the cosmological singularity. A preliminary study of this dual theory suggests that the big crunch is an endpoint of evolution even in the full string theory. We also show that any theory with scalar solitons must have negative energy solutions. The results presented here clarify our earlier work on cosmic censorship violation in N=8 supergravity. (author)

In-situ observation system for dual ion irradiation damage

International Nuclear Information System (INIS)

Furuno, Shigemi; Hojou, Kiichi; Otsu, Hitoshi; Sasaki, T.A.; Izui, Kazuhiko; Tukamoto, Tetsuo; Hata, Takao.

1992-01-01

We have developed an in-situ observation and analysis system during dual ion beam irradiation in an electron microscope. This system consists of an analytical electron microscope of JEM-4000FX type equipped with a parallel EELS and an EDS attachments and linked with two sets of ion accelerators of 40 kV. Hydrogen and helium dual-ion beam irradiation experiments were performed for SiC crystals. The result of dual-ion beam irradiation was compared with those of helium and hydrogen single ion irradiations. It is clearly seen that the dual-ion irradiation has the effect of suppressing bubble formation and growth in comparison with the case of single helium ion irradiation. (author)

Constructing pairs of dual bandlimited framelets with desired time localization

DEFF Research Database (Denmark)

Lemvig, Jakob

2009-01-01

combination of dilations of ψ with explicitly given coefficients. The result allows a simple construction procedure for pairs of dual wavelet frames whose generators have compact support in the Fourier domain and desired time localization. The construction is based on characteriszing equations for dual......For sufficiently small translation parameters, we prove that any bandlimited function ψ, for which the dilations of its Fourier transform form a partition of unity, generates a wavelet frame with a dual frame also having the wavelet structure. This dual frame is generated by a finite linear...

Constructing pairs of dual bandlimited framelets with desired time localization

DEFF Research Database (Denmark)

Lemvig, Jakob

combination of dilations of ψ with explicitly given coefficients. The result allows a simple construction procedure for pairs of dual wavelet frames whose generators have compact support in the Fourier domain and desired time localization. The construction is based on characteriszing equations for dual......For sufficiently small translation parameters, we prove that any bandlimited function ψ, for which the dilations of its Fourier transform form a partition of unity, generates a wavelet frame with a dual frame also having the wavelet structure. This dual frame is generated by a finite linear...

Temporal subtraction of dual-energy chest radiographs

International Nuclear Information System (INIS)

Armato, Samuel G. III; Doshi, Devang J.; Engelmann, Roger; Caligiuri, Philip; MacMahon, Heber

2006-01-01

Temporal subtraction and dual-energy imaging are two enhanced radiography techniques that are receiving increased attention in chest radiography. Temporal subtraction is an image processing technique that facilitates the visualization of pathologic change across serial chest radiographic images acquired from the same patient; dual-energy imaging exploits the differential relative attenuation of x-ray photons exhibited by soft-tissue and bony structures at different x-ray energies to generate a pair of images that accentuate those structures. Although temporal subtraction images provide a powerful mechanism for enhancing visualization of subtle change, misregistration artifacts in these images can mimic or obscure abnormalities. The purpose of this study was to evaluate whether dual-energy imaging could improve the quality of temporal subtraction images. Temporal subtraction images were generated from 100 pairs of temporally sequential standard radiographic chest images and from the corresponding 100 pairs of dual-energy, soft-tissue radiographic images. The registration accuracy demonstrated in the resulting temporal subtraction images was evaluated subjectively by two radiologists. The registration accuracy of the soft-tissue-based temporal subtraction images was rated superior to that of the conventional temporal subtraction images. Registration accuracy also was evaluated objectively through an automated method, which achieved an area-under-the-ROC-curve value of 0.92 in the distinction between temporal subtraction images that demonstrated clinically acceptable and clinically unacceptable registration accuracy. By combining dual-energy soft-tissue images with temporal subtraction, misregistration artifacts can be reduced and superior image quality can be obtained

Dual Dynamic Programming - DDP

International Nuclear Information System (INIS)

Velasquez Bermudez, Jesus M

1998-01-01

Objections are presented to the mathematical formulation of the denominated Dual Dynamic programming-PDD that is the theoretical base of several computational model available for the optimal formulation of interconnected hydrothermal systems

Determination of HER-2 status on FNAC material from breast carcinomas using in situ hybridization with dual chromogen visualization with silver enhancement (dual SISH

Directory of Open Access Journals (Sweden)

Beraki Elsa

2010-01-01

Full Text Available During the last years, HER-2 status kits and protocols for chromogen visualization of hybridization signals have come on the market. The first generation using chromogen visualization used single color probes. The second generation, now emerging on the market, uses dual chromogen visualization. The aim of this study has been to test a new dual color chromogen kit (Ventana INFORM HER2 Dual Colour ISH Roche ® and compare the results with our in-house method(s. The material consisted primarily of cytological material from invasive breast carcinomas in 49 women. Dual SISH was done on all 49 cytological and histological specimens. The histological specimens were treated according to the manufacturer′s recommendations. The procedure was modified in several steps in order to adapt it to the cytological material. Hybridization failed in two cytological specimens. Dual SISH showed concordant results on cytological and histological material as to amplified/not amplified. The included cases had the same HER-2 expression in the invasive and the in situ components on histology. Four IDC showed HER-2 amplification (8.5%. Polysomy was found in two cases. All dual SISH results except for one concurred with the results of the in-house method(s (1/47=2.1%. The dual SISH is suitable for cytological examination of HER-2 status. The protocol must be optimized for cytological material.

N = (2,0) self-dual non-Abelian tensor multiplet in D = 3 + 3 generates N = (1,1) self-dual systems in D = 2 + 2

Science.gov (United States)

Nishino, Hitoshi; Rajpoot, Subhash

2018-03-01

We formulate an N = (2 , 0) system in D = 3 + 3 dimensions consisting of a Yang-Mills (YM)-multiplet (ˆ μ ˆ IA, λˆI), a self-dual non-Abelian tensor multiplet (ˆ μ ˆ ν ˆ IB, χˆI ,φˆI), and an extra vector multiplet (C ˆ μ ˆ IC, ρˆI). We next perform the dimensional reductions of this system into D = 2 + 2, and obtain N = (1 , 1) systems with a self-dual YM-multiplet (AIμ ,λI), a self-dual tensor multiplet (BIμν , χI , φI), and an extra vector multiplet (CIμ , ρI). In D = 2 + 2, we reach two distinct theories: 'Theory-I' and 'Theory-II'. The former has the self-dual field-strength Hμν(+)I of CIμ already presented in our recent paper, while the latter has anti-self-dual field strength Hμν(-)I. As an application, we show that Theory-II actually generates supersymmetric-KdV equations in D = 1 + 1. Our result leads to a new conclusion that the D = 3 + 3 theory with non-Abelian tensor multiplet can be a 'Grand Master Theory' for self-dual multiplet and self-dual YM-multiplet in D = 2 + 2, that in turn has been conjectured to be the 'Master Theory' for all supersymmetric integrable theories in D ≤ 3.

Reliability of the dual-isotope Schilling test for the diagnosis of pernicious anemia or malabsorption syndrome

International Nuclear Information System (INIS)

Domstad, P.A.; Choy, Y.C.; Kim, E.E.; DeLand, F.H.

1981-01-01

To evaluate the dual-isotope Schilling test for the diagnosis of pernicious anemia or malabsorption syndrome, 65 studies were selected for clinical correlation. Criteria for pernicious anemia included mean corpuscular volume greater than 100 cu micrometer, serum B12 greater than 100 ng/l, megaloblastic marrow, achlorhydria, reticulocytes greater than 5% on B12 therapy, atrophic gastritis, and elevated serum antibodies to parietal cells or intrinsic factor. Criteria for malabsorption syndrome included: decreased serum B12, folate, and carotene; increased fecal fat; abnormal D-xylose absorption; abnormal radiographic and biopsy findings. 58 Co-cyanocobalamin and 57 Co-cyanocobalamin bound to intrinsic factor were given orally to fasting patients; 1 mg of nonradioactive B12 was injected intramuscularly within two hours. Aliquots of 24-hour urine samples were counted. If the excretion of 58 Co was less than 7% and the 57 Co/ 58 Co ratio was greater than 1.7, the test indicated pernicious anemia; a ratio less than 1.7 indicated malabsorption syndrome. Sensitivity, specificity, and accuracy of the dual-isotope Schilling test were 83%, 98%, and 94% for pernicious anemia, and 67%, 90%, and 86% for malabsorption syndrome, respectively

Biological activities of a new compound isolated from the aerial parts ...