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Sample records for double isobaric analog

  1. Excitation energies of double isobar-analog states in heavy nuclei

    SciTech Connect

    Poplavskii, I. V.

    1988-12-01

    Several new relationships are established for isomultiplets on the basis of a theory in which the Coulomb coupling constant (CCC) is allowed to be complex. In particular, the following rule is formulated: the energies for fission or decay of members of an isomultiplet into a charged cluster and members of the corresponding daughter isomultiplet are equidistant. This relationship is well satisfied for isomultiplets with /ital A/less than or equal to60. By extrapolating the rule for fission and decay energies to the region of heavy nuclei, the excitation energies /ital E//sub /ital x// of double isobar-analog states (DIASs) are found for the nuclei /sup 197,199/Hg, /sup 205/Pb, /sup 205 - -209/Po, /sup 209/At, and /sup 238/Pu. A comparison of the computed energies /ital E//sub /ital x// with the experimentally measured values for /sup 208/Po attest to the reliability and good accuracy of the method proposed here when used to determine the excitation energies of DIASs in heavy nuclei.

  2. Observation of the double isobaric analog transition 18O(π+,π-) 18Ne at 50 MeV

    NASA Astrophysics Data System (ADS)

    Altman, A.; Johnson, R. R.; Wienands, U.; Hessey, N.; Barnett, B. M.; Forster, B. M.; Grion, N.; Mills, D.; Rozon, F. M.; Smith, G. R.; Trelle, And R.; Gill, D. R.; Sheffer, G.; Anderl, T.

    1985-09-01

    The angular distribution of the differential cross sections for the transition to the double isobaric analog state in the reaction 18(π+,π-) 18Ne was measured at six angles from 20° to 120°. Extrapolation of the differential cross section results in 5.3+/-0.5 μb/sr at 0° and an angle-integrated cross section of 16.7+/-1.2 μb. The forward peaking and magnitude of the cross sections differ from those predicted by simple sequential models and the trends of data at higher energies. The results are compared to recent data for the same transition on 14C at 50 MeV and to a calculation in the six-quark bag model.

  3. Survey of Evaluated Isobaric Analog States

    SciTech Connect

    MacCormick, M.

    2014-06-15

    Isobaric analog states (IAS) can be used to estimate the masses of members belonging to the same isospin multiplet. Experimental and estimated IAS have been used frequently within the Atomic Mass Evaluation (AME) in the past, but the associated set of evaluated masses have been published for the first time in AME2012 and NUBASE2012. In this paper the current trends of the isobaric multiplet mass equation (IMME) coefficients are shown. The T = 2 multiplet is used as a detailed illustration.

  4. Symmetry energy II: Isobaric analog states

    NASA Astrophysics Data System (ADS)

    Danielewicz, Pawel; Lee, Jenny

    2014-02-01

    Using excitation energies to isobaric analog states (IAS) and charge invariance, we extract nuclear symmetry coefficients, representing a mass formula, on a nucleus-by-nucleus basis. Consistently with charge invariance, the coefficients vary weakly across an isobaric chain. However, they change strongly with nuclear mass and range from aa˜10 MeV at mass A˜10 to aa˜22 MeV at A˜240. Variation with mass can be understood in terms of dependence of nuclear symmetry energy on density and the rise in importance of low densities within nuclear surface in smaller systems. At A≳30, the dependence of coefficients on mass can be well described in terms of a macroscopic volume-surface competition formula with aaV≃33.2 MeV and aaS≃10.7 MeV. Our further investigation shows, though, that the fitted surface symmetry coefficient likely significantly underestimates that for the limit of half-infinite matter. Following the considerations of a Hohenberg-Kohn functional for nuclear systems, we determine how to find in practice the symmetry coefficient using neutron and proton densities, even when those densities are simultaneously affected by significant symmetry-energy and Coulomb effects. These results facilitate extracting the symmetry coefficients from Skyrme-Hartree-Fock (SHF) calculations, that we carry out using a variety of Skyrme parametrizations in the literature. For the parametrizations, we catalog novel short-wavelength instabilities. In our further analysis, we retain only those parametrizations which yield systems that are adequately stable both in the long- and short-wavelength limits. In comparing the SHF and IAS results for the symmetry coefficients, we arrive at narrow (±2.4 MeV) constraints on the symmetry-energy values S(ρ) at 0.04≲ρ≲0.13 fm. Towards normal density the constraints significantly widen, but the normal value of energy aaV and the slope parameter L are found to be strongly correlated. To narrow the constraints, we reach for the

  5. Coupled-channel Treatment of Isobaric Analog Resonances in (p,p‧) Capture Processes

    NASA Astrophysics Data System (ADS)

    Thompson, I. J.; Arbanas, G.

    2014-04-01

    With the advent of nuclear reactions on unstable isotopes, there has been a renewed interest in using isobaric analogue resonances (IAR) as a tool for probing the nuclear structure. The position and width of isobaric analogue resonances in nucleon-nucleus scattering are accurate and detailed indicators of the positions of resonances and bound states with good single-particle characters. We report on implementation within our coupled-channels code FRESCO of the charge-exchange interaction term that transforms an incident proton into a neutron. Isobaric analog resonances are seen as peaks in γ-ray spectrum when the proton is transformed into a neutron at an energy near a neutron bound state. The Lane coupled-channels formalism was extended to follow the non-orthogonality of this neutron channel with that configuration of an inelastic outgoing proton, and the target being left in a particle-hole excited state. This is tested for 208Pb, for which good (p,p'γ) coincidence data exists.

  6. Coupled-channel treatment of Isobaric Analog Resonances in (p,p') Capture Processes

    SciTech Connect

    Thompson, I J; Arbanas, Goran

    2013-01-01

    With the advent of nuclear reactions on unstable isotopes, there has been a renewed interest in using isobaric analogue resonances (IAR) as a tool for probing the nuclear structure. The position and width of isobaric analogue resonances in nucleon-nucleus scattering are accurate and detailed indicators of the positions of resonances and bound states with good single-particle characters. We report on implementation within our coupled-channels code FRESCO of the charge-exchange interaction term that transforms an incident proton into a neutron. Isobaric analog resonances are seen as peaks in gamma-ray spectrum when the proton is transformed into a neutron at an energy near a neutron bound state. The Lane coupled-channels formalism was extended to follow the nonorthogonality of this neutron channel with that configuration of an inelastic outgoing proton, and the target being left in a particle-hole excited state. This is tested for 208Pb, for which good (p,p g)

  7. Two-proton decay from Isobaric Analog States of light nuclei

    NASA Astrophysics Data System (ADS)

    Brown, Kyle

    2014-03-01

    Recent experiments at the National Superconducting Cyclotron Laboratory at Michigan State University using the charged-particle array HiRA and the gamma-ray array CAESAR have shed light on a new class of two-proton emitters associated with Isobaric Analog States (IAS). The two-proton decay is to the Isobaric Analog state of the daughter, which then gamma decays. These isospin-allowed transitions occur when one-proton decays are forbidden by either energy or isospin conservation, and when two-proton decay to the ground state is isospin forbidden. Three possible examples of this decay path will be discussed (8BIAS, 12NIAS, and 16FIAS) . The known IAS of 8C in 8B was confirmed to decay by two-proton emission to the 3.56 MeV IAS in 6Li. While the IAS in 8B was previously known, it was measured in this experiment with unbiased statistics and in coincidence with the 3.56 MeV gamma-ray. The IAS in 16F was investigated for the first time in this experiment and is still under investigation. Previous work on the IAS of 12O in 12N at the Cyclotron Institute at Texas A&M will also be presented.

  8. Split Isobaric Analog State in Ni55: Case of Strong Isospin Mixing

    NASA Astrophysics Data System (ADS)

    Tripathi, Vandana; Tabor, S. L.; Volya, A.; Liddick, S. N.; Bender, P. C.; Larson, N.; Prokop, C.; Suchyta, S.; Tai, P.-L.; VonMoss, J. M.

    2013-12-01

    Study of β+ decay of the exotic Tz=-3/2 nucleus Cu55, via delayed γ rays, has revealed a strongly isospin mixed doublet (4599-4579 keV) in Ni55, which represents the fragmented and previously unknown isobaric analog of the ground state of Cu55. The observed small log ft values to both states in the doublet confirm the superallowed Fermi β decay. The near degeneracy of a pair of 3/2- levels in Ni55 results in the strong isospin mixing. The isospin mixing matrix element between the T =3/2 and T=1/2 levels is inferred from the experiment to be 9(1) keV, which agrees well with the matrix element of the charge symmetry breaking shell model Hamiltonian of Ormand and Brown. A precise value of the half-life of Cu55 at 57(3) ms was also obtained.

  9. The Isospin Admixture of The Ground State and The Properties of The Isobar Analog Resonances In Deformed Nuclei

    SciTech Connect

    Aygor, H. Ali; Maras, Ismail; Cakmak, Necla; Selam, Cevad

    2008-11-11

    Within quasiparticle random phase approximation (QRPA), Pyatov-Salamov method for the self-consistent determination of the isovector effective interaction strength parameter, restoring a broken isotopic symmetry for the nuclear part of the Hamiltonian, is used. The isospin admixtures in the ground state of the parent nucleus, and the isospin structure of the isobar analog resonance (IAR) state are investigated by including the pairing correlations between nucleons for {sup 72-80}Kr isotopes. Our results are compared with the spherical case and with other theoretical results.

  10. Multichannel study on the fragmentation of the 1g9/2 isobaric analog resonance in 53Mn

    NASA Astrophysics Data System (ADS)

    Sziklai, J.; Cameron, J. A.; Szöghy, I. M.; Vass, T.

    1994-02-01

    Fragments of the 1g9/2 isobaric analog resonance in 53Mn corresponding to the 3.715 MeV state (Sn=0.57) in 53Cr were located using the 52Cr(p,p0), 52Cr(p,p1), 52Cr(p,p1γ), 52Cr(p,p2γ), and 52Cr(p,γ)53Mn reactions. Differential cross sections were measured in the 4.06-4.28 MeV, and the γ-excitation curves in the 4.04-4.35 MeV proton energy region. Spins, parities, and partial widths were determined with the aid of R-matrix analysis for all resonances observed in the region. The spins of the 1g9/2 resonance fragments were found independently from (p,p1γ), (p,p2γ), and (p,γ) angular distribution measurements and their analyses. Nineteen fragments were identified and their γ-branching ratios to low lying levels of 53Mn were also deduced. Partial widths for each fragment in all four channels were derived. Channel-channel correlations were calculated. Fine structure analyses were carried out in all open channels. Inelastic spectroscopic factors and Coulomb displacement energy for the 1g9/2 state were also derived.

  11. Charge-Exchange Excitation of the Isobaric Analog State and Implication for the Nuclear Symmetry Energy and Neutron Skin

    NASA Astrophysics Data System (ADS)

    Khoa, Dao T.; Loc, Bui Minh; Zegers, R. G. T.

    The charge-exchange (p, n) or (3He,t) reaction can be considered as elastic scattering of proton or 3He by the isovector term of the optical potential that flips the projectile isospin. Therefore, the accurately measured charge-exchange scattering cross section for the isobaric analog states can be a good probe of the isospin dependence of the optical potential, which is determined exclusively within the folding model by the difference between the neutron and proton densities and isospin dependence of the nucleon-nucleon interaction. On the other hand, the same isospin- and density-dependent nucleon-nucleon interaction can also be used in a Hartree-Fock calculation of asymmetric nuclear matter, to estimate the nuclear matter energy and its asymmetry part. As a result, the fine-tuning of the isospin dependence of the effective nucleon-nucleon interaction against the measured (p, n) or (3He,t) cross sections should allow us to make some realistic prediction of the nuclear symmetry energy and its density dependence. Moreover, given the neutron skin of the target related directly to the neutron-proton difference of the ground-state density, it can be well probed in the analysis of the charge-exchange (3He,t) reactions at medium energies when the two-step processes can be neglected and the t-matrix interaction can be used in the folding calculation.

  12. Identification of the Lowest T =2 , Jπ=0+ Isobaric Analog State in 52Co and Its Impact on the Understanding of β -Decay Properties of 52Ni

    NASA Astrophysics Data System (ADS)

    Xu, X.; Zhang, P.; Shuai, P.; Chen, R. J.; Yan, X. L.; Zhang, Y. H.; Wang, M.; Litvinov, Yu. A.; Xu, H. S.; Bao, T.; Chen, X. C.; Chen, H.; Fu, C. Y.; Kubono, S.; Lam, Y. H.; Liu, D. W.; Mao, R. S.; Ma, X. W.; Sun, M. Z.; Tu, X. L.; Xing, Y. M.; Yang, J. C.; Yuan, Y. J.; Zeng, Q.; Zhou, X.; Zhou, X. H.; Zhan, W. L.; Litvinov, S.; Blaum, K.; Audi, G.; Uesaka, T.; Yamaguchi, Y.; Yamaguchi, T.; Ozawa, A.; Sun, B. H.; Sun, Y.; Dai, A. C.; Xu, F. R.

    2016-10-01

    Masses of 52g,52mCo were measured for the first time with an accuracy of ˜10 keV , an unprecedented precision reached for short-lived nuclei in the isochronous mass spectrometry. Combining our results with the previous β -γ measurements of 52Ni, the T =2 , Jπ=0+ isobaric analog state (IAS) in 52Co was newly assigned, questioning the conventional identification of IASs from the β -delayed proton emissions. Using our energy of the IAS in 52Co, the masses of the T =2 multiplet fit well into the isobaric multiplet mass equation. We find that the IAS in 52Co decays predominantly via γ transitions while the proton emission is negligibly small. According to our large-scale shell model calculations, this phenomenon has been interpreted to be due to very low isospin mixing in the IAS.

  13. Isobar analog states (IAS), double isobar analog states (DIAS), configuration states (CS), and double configuration states (DCS) in halo nuclei. Halo isomers

    SciTech Connect

    Izosimov, I. N.

    2015-10-15

    It has been shown that IAS, DIAS, CS, and DCS can simultaneously have n-n, n-p, and p-p halo components in their wave functions. Differences in halo structure of the excited and ground states can result in the formation of isomers (halo-isomers). Both the Borromean and tango halo types can be observed for n-p configurations of atomic nuclei. The structure of the ground and excited states with different isospin quantum number in halo like nuclei is discussed. B(Mλ) and B(Eλ) for γ-transitions in {sup 6,7,8}Li, {sup 8,9,10}Be, {sup 8,10,11}B, {sup 10,11,12,13,14}C, {sup 13,14,15,16,17}N, {sup 15,16,17,19}O, and {sup 17}F are analyzed. Special attention is given to nuclei whose ground state does not exhibit halo structure but the excited state may have one.

  14. Isobar analog states (IAS), double isobar analog states (DIAS), configuration states (CS), and double configuration states (DCS) in halo nuclei. Halo isomers

    NASA Astrophysics Data System (ADS)

    Izosimov, I. N.

    2015-10-01

    It has been shown that IAS, DIAS, CS, and DCS can simultaneously have n-n, n-p, and p-p halo components in their wave functions. Differences in halo structure of the excited and ground states can result in the formation of isomers (halo-isomers). Both the Borromean and tango halo types can be observed for n-p configurations of atomic nuclei. The structure of the ground and excited states with different isospin quantum number in halo like nuclei is discussed. B(Mλ) and B(Eλ) for γ-transitions in 6,7,8Li, 8,9,10Be, 8,10,11B, 10,11,12,13,14C, 13,14,15,16,17N, 15,16,17,19O, and 17F are analyzed. Special attention is given to nuclei whose ground state does not exhibit halo structure but the excited state may have one.

  15. Nuclear structure beyond the neutron drip line: The lowest energy states in 9He via their T = 5/2 isobaric analogs in 9Li

    NASA Astrophysics Data System (ADS)

    Uberseder, E.; Rogachev, G. V.; Goldberg, V. Z.; Koshchiy, E.; Roeder, B. T.; Alcorta, M.; Chubarian, G.; Davids, B.; Fu, C.; Hooker, J.; Jayatissa, H.; Melconian, D.; Tribble, R. E.

    2016-03-01

    The level structure of the very neutron rich and unbound 9He nucleus has been the subject of significant experimental and theoretical study. Many recent works have claimed that the two lowest energy 9He states exist with spins Jπ = 1 /2+ and Jπ = 1 /2- and widths on the order of 100-200 keV. These findings cannot be reconciled with our contemporary understanding of nuclear structure. The present work is the first high-resolution study with low statistical uncertainty of the relevant excitation energy range in the 8He+n system, performed via a search for the T = 5 / 2 isobaric analog states in 9Li populated through 8He+p elastic scattering. The present data show no indication of any narrow structures. Instead, we find evidence for a broad Jπ = 1 /2+ state in 9He located approximately 3 MeV above the neutron decay threshold.

  16. Nuclear structure beyond the neutron drip line. The lowest energy states in 9He via their T=5/2 isobaric analogs in 9Li

    DOE PAGES

    Uberseder, E.; Rogachev, G. V.; Goldberg, V. Z.; ...

    2016-03-01

    The level structure of the very neutron rich and unbound 9He nucleus has been the subject of significant experimental and theoretical study. Many recent works have claimed that the two lowest energy 9He states exist with spins Jπ=1/2+and Jπ=1/2-and widths on the order of 100–200 keV. These find-ings cannot be reconciled with our contemporary understanding of nuclear structure. Our present work is the first high-resolution study with low statistical uncertainty of the relevant excitation energy range in the 8He+n system, performed via a search for the T =5/2 isobaric analog states in 9Li populated through 8He+p elastic scattering. Moreover, themore » present data show no indication of any narrow structures. Instead, we find evidence for a broad Jπ=1/2+state in 9He located approximately 3 MeV above the neutron decay threshold.« less

  17. Pion single- and double-charge-exchange reactions at low energies

    SciTech Connect

    Baer, H.W.

    1987-01-01

    The general features of pion charge-exchange reactions at energies of 20 to 80 MeV leading to nuclear isobaric-analog states (IAS) and double-isobaric-analog states (DIAS) are reviewed. The recent progress achieved in understanding the role of short-range N-N correlations in the double-charge-exchange reactions is presented. 36 refs., 21 figs., 2 tabs.

  18. Playing with a double-edged sword: Analogies in biochemistry

    NASA Astrophysics Data System (ADS)

    Orgill, Marykay

    Analogy pervades our everyday reasoning. No situation we encounter is exactly like a situation we have encountered previously, and our ability to learn and survive in the world is based on our ability to find similarities between past and present situations and use the knowledge we have gained from past situations to manage current situations. Analogies can be powerful teaching tools because they can make new material intelligible to students by comparing it to material that is already familiar. It is clear, though, that not all analogies are good and that not all good analogies are useful to all students. In this study, I have used textbook analysis, classroom observations, student interviews and instructor interviews to determine the role that analogies play in biochemistry learning. Analogies are an important teaching technique in biochemistry classes, being used more often in both biochemistry classes and textbooks than they are in high school chemistry classes and textbooks. Most biochemistry students like, pay particular attention to, and remember the analogies their instructors provide; and they use these analogies to understand, visualize, and recall information from class. Even though students like and use analogies, they do not understand what analogies are or the mechanism by which they improve learning. For the students, analogies are simply any teaching technique that eases understanding, visualization, or recall. Instructors, on the other hand, have a good understanding of what analogies are and of how they should be presented in class; but they do not use analogies as effectively as they should. They do not plan, explain or identify the limitations of the analogies they use in class. However, regardless of how effectively instructors present analogies in class, this study indicates that, in general, analogies are useful in promoting understanding, visualization, recall, and motivation in biochemistry students at all levels. They would be even more

  19. Nuclear structure beyond the neutron drip line. The lowest energy states in 9He via their T=5/2 isobaric analogs in 9Li

    SciTech Connect

    Uberseder, E.; Rogachev, G. V.; Goldberg, V. Z.; Koshchiy, E.; Roeder, B. T.; Alcorta, M.; Chubarian, G.; Davids, B.; Fu, C.; Hooker, J.; Jayatissa, H.; Melconian, D.; Tribble, R. E.

    2016-03-01

    The level structure of the very neutron rich and unbound 9He nucleus has been the subject of significant experimental and theoretical study. Many recent works have claimed that the two lowest energy 9He states exist with spins Jπ=1/2+and Jπ=1/2-and widths on the order of 100–200 keV. These find-ings cannot be reconciled with our contemporary understanding of nuclear structure. Our present work is the first high-resolution study with low statistical uncertainty of the relevant excitation energy range in the 8He+n system, performed via a search for the T =5/2 isobaric analog states in 9Li populated through 8He+p elastic scattering. Moreover, the present data show no indication of any narrow structures. Instead, we find evidence for a broad Jπ=1/2+state in 9He located approximately 3 MeV above the neutron decay threshold.

  20. Double charge exchange on Te isotopes in the generalized seniority scheme

    SciTech Connect

    Wu, H.C. |; Ginocchio, J.N.; Dieperink, A.E.; Scholten, O.

    1996-09-01

    The pion double-charge-exchange reactions on the Te isotopes are discussed in the generalized seniority scheme. The elementary process of charge exchange is described in a double scattering process within the plane wave limit. The transition rates are calculated for double-isobaric-analog state as well as for ground-state reactions. {copyright} {ital 1996 The American Physical Society.}

  1. Pion production via isobar giant resonance formation and decay

    NASA Technical Reports Server (NTRS)

    Townsend, L. W.; Deutchman, P. A.; Madigan, R. L.; Norbury, J. W.

    1984-01-01

    A spin, isotopic-spin formalism for the production of pions due to decays of isobar giant resonances formed in peripheral heavy-ion collisions is presented. The projectile nucleus isobar giant resonance state is assumed to coherently form and then incoherently decay to produce the pions. Total spin and isotopic spin for the system are conserved through the concomitant excitation of the target nucleus to an isobaric analog giant resonance state. Comparisons of the predicted total pion cross sections, over a range of energies, are made with heavy-ion pion data.

  2. Concise nuclear isobar charts

    SciTech Connect

    Bucka, H.

    1986-01-01

    In the Concise Nuclear Isobar Charts, data on binding energies of protons and neutrons in the ground state and excitation energies for low-lying nuclear energy levels are displayed, both of which are of great interest for transition processes as well as for questions of nuclear structure. Also, quantum numbers for angular momentum and parity are shown for these energy levels. For the stable nuclei, data for the relative abundances, and for unstable nucleon configurations, the transition probabilities are included in the data displayed. Due to the representation chosen for the atomic nuclei, in many cases a very clear first survey of systematic properties of nuclear energy states as well as spontaneous decay processes is achieved.

  3. Isobaric groundwater well

    DOEpatents

    Hubbell, Joel M.; Sisson, James B.

    1999-01-01

    A method of measuring a parameter in a well, under isobaric conditions, including such parameters as hydraulic gradient, pressure, water level, soil moisture content and/or aquifer properties the method as presented comprising providing a casing having first and second opposite ends, and a length between the ends, the casing supporting a transducer having a reference port; placing the casing lengthwise into the well, second end first, with the reference port vented above the water table in the well; and sealing the first end. A system is presented for measuring a parameter in a well, the system comprising a casing having first and second opposite ends, and a length between the ends and being configured to be placed lengthwise into a well second end first; a transducer, the transducer having a reference port, the reference port being vented in the well above the water table, the casing being screened across and above the water table; and a sealing member sealing the first end. In one embodiment, the transducer is a tensiometer transducer and in other described embodiments, another type transducer is used in addition to a tensiometer.

  4. The anaesthetic and recovery profile of two concentrations (0.25% and 0.50%), of intrathecal isobaric levobupivacaine for combined spinal-epidural (CSE) anaesthesia in patients undergoing modified Stark method caesarean delivery: a double blinded randomized trial.

    PubMed

    D'Ambrosio, A; Spadaro, S; Mirabella, L; Natale, C; Cotoia, A; De Capraris, A; Menga, R; Salatto, P; Malvasi, A; Brizzi, A; Tinelli, A; Dambrosio, M; Cinnella, G

    2013-12-01

    In spinal anaesthesia for a Caesarean delivery, it is important to limit anaesthesia only at the surgical area, and to resolve fast motor block. We compared the intraoperative effectiveness, hemodynamic effects, anaesthetic recovery times and patients satisfaction after isobaric levobupivacaine (L) 0.25% versus L0.50% spinal anaesthesia during elective Caesarean deliveries performed with the Stark technique. In this double-blinded prospective study, seventy women undergoing elective caesarean delivery were randomized to receive either intrathecal 7.5 mg Levobupivacaine 0.25% plus sufentanil 2.5 μg (Group L0.25), or intrathecal 7.5 mg L 0.50% plus sufentanil 2.5 μg (GroupControl). The onset time, duration of anaesthesia, analgesia and sensory and motor block and hemodynamic parameters were measured from the beginning of spinal anaesthesia until four hours after spinal anaesthesia (T240). Onset time, duration of anaesthesia and haemodynamic variations were similar in the two groups. No patients required general anesthesia to complete surgery. Motor block vanished faster in Group L0.25 as compared with GroupControl (p < .01). The cephalad spread of the 0.50% solution was higher than that of the 0.25% solution: no patient in Group L0.25 experienced paresthesia of the upper limbs vs 14% in GroupControl (p < .05). In GroupControl anaesthesia reached the dermatome T1 in 15% of cases. Maternal and surgeon satisfaction was good in every patient. Levobupivacaine 7.5 milligrams at 0.25% may be used as a suitable alternative to L 0.50% for spinal anaesthesia for caesarean deliveris with the Stark technique with good maternal satisfaction. In Group L0.25 a lower appearance of nausea and hypotension were observed and motor and sensitive block developed and diminished faster while no clinically significant differences in hemodynamic behavior was observed between groups.

  5. Double negative elastic metamaterial design through electrical-mechanical circuit analogies.

    PubMed

    Pope, Simon A

    2013-07-01

    Previous studies into solid elastic metamaterials which have a simultaneously negative effective bulk modulus and density have proposed designs for materials with relatively narrow bandwidths, because of the reliance on resonators to provide the dispersive material properties. Some of the proposed novel applications for metamaterials, such as invisibility cloaks and sub-wavelength lenses, generally require materials with inherently larger bandwidths for practical exploitation. In this paper, a well-known electromagnetic metamaterial design is used together with the electrical-mechanical circuit analogies to propose a simultaneously double negative elastic metamaterial design which does not suffer from the narrow bandwidth constraints of previous designs. An interesting consequence of the proposed design is that it has an effective wavelength which asymptotically goes to infinity with frequency.

  6. Interpreting nonlinear vibrational spectroscopy with the classical mechanical analogs of double-sided Feynman diagrams.

    PubMed

    Noid, W G; Loring, Roger F

    2004-10-15

    Observables in coherent, multiple-pulse infrared spectroscopy may be computed from a vibrational nonlinear response function. This response function is conventionally calculated quantum-mechanically, but the challenges in applying quantum mechanics to large, anharmonic systems motivate the examination of classical mechanical vibrational nonlinear response functions. We present an approximate formulation of the classical mechanical third-order vibrational response function for an anharmonic solute oscillator interacting with a harmonic solvent, which establishes a clear connection between classical and quantum mechanical treatments. This formalism permits the identification of the classical mechanical analog of the pure dephasing of a quantum mechanical degree of freedom, and suggests the construction of classical mechanical analogs of the double-sided Feynman diagrams of quantum mechanics, which are widely applied to nonlinear spectroscopy. Application of a rotating wave approximation permits the analytic extraction of signals obeying particular spatial phase matching conditions from a classical-mechanical response function. Calculations of the third-order response function for an anharmonic oscillator coupled to a harmonic solvent are compared to numerically correct classical mechanical results.

  7. Reference pressure changes and available potential energy in isobaric coordinates

    NASA Technical Reports Server (NTRS)

    Robertson, F. R.

    1985-01-01

    A formulation of the available potential energy (APE) equation in isobaric coordinates which alleviates the need for computing temporal derivatives of reference pressure and describes how work done relates to changes in the APE of a limited region is presented. The APE budget equation possesses terms analogous to those in Johnson's (1970) isentropic version. It is shown that APE changes result from either mechanical work inside the domain or an exchange of energy via boundary processes with the surrounding environment.

  8. Reference pressure changes and available potential energy in isobaric coordinates

    NASA Technical Reports Server (NTRS)

    Robertson, F. R.

    1985-01-01

    A formulation of the available potential energy (APE) equation in isobaric coordinates which alleviates the need for computing temporal derivatives of reference pressure and describes how work done relates to changes in the APE of a limited region is presented. The APE budget equation possesses terms analogous to those in Johnson's (1970) isentropic version. It is shown that APE changes result from either mechanical work inside the domain or an exchange of energy via boundary processes with the surrounding environment.

  9. High-precision mass measurements for the isobaric multiplet mass equation at A = 52

    NASA Astrophysics Data System (ADS)

    Nesterenko, D. A.; Kankainen, A.; Canete, L.; Block, M.; Cox, D.; Eronen, T.; Fahlander, C.; Forsberg, U.; Gerl, J.; Golubev, P.; Hakala, J.; Jokinen, A.; Kolhinen, V. S.; Koponen, J.; Lalović, N.; Lorenz, Ch; Moore, I. D.; Papadakis, P.; Reinikainen, J.; Rinta-Antila, S.; Rudolph, D.; Sarmiento, L. G.; Voss, A.; Äystö, J.

    2017-06-01

    Masses of 52Co, 52Co m , 52Fe, 52Fe m , and 52Mn have been measured with the JYFLTRAP double Penning trap mass spectrometer. The isobaric multiplet mass equation for the T = 2 quintet at A = 52 has been studied employing the new mass values. No significant breakdown (beyond the 3σ level) of the quadratic form of the IMME was observed ({χ }2/n=2.4). The cubic coefficient was 6.0(32) keV ({χ }2/n=1.1). The excitation energies for the isomer and the T = 2 isobaric analog state in 52Co have been determined to be 374(13) keV and 2922(13) keV, respectively. The measured mass values for 52Co and 52Co m are 29(10) keV and 16(15) keV higher, respectively, than obtained in a recent storage-ring experiment, and significantly lower than predicted by extrapolations. Consequently, this has an impact on the proton separation energies for 52Co and 53Ni relevant for the astrophysical rapid proton capture process. The Q value for the proton decay from the 19/{2}- isomer in 53Co has been determined with an unprecedented precision, {Q}p=1558.8(17) keV.

  10. Improved analog/RF performance of double gate junctionless MOSFET using both gate material engineering and drain/source extensions

    NASA Astrophysics Data System (ADS)

    Chebaki, E.; Djeffal, F.; Ferhati, H.; Bentrcia, T.

    2016-04-01

    In this paper, we propose a new Double Gate Junctionless (DGJ) MOSFET design based on both gate material engineering and drain/source extensions. Analytical models for the long channel device associated to the drain current, analog and radio-frequency (RF) performance parameters are developed incorporating the impact of dual-material gate engineering and two highly doped extension regions on the analog/RF performance of DGJ MOSFET. The transistor performance figures-of-merit (FoM), governing the analog/RF behavior, have also been analyzed. The analog/RF performance is compared between the proposed design and a conventional DGJ MOSFET of similar dimensions, where the proposed device shows excellent ability in improving the analog/RF performance and provides higher drain current and improved figures-of-merit as compared to the conventional DGJ MOSFET. The obtained results have been validated against the data obtained from TCAD software for a wide range of design parameters. Moreover, the developed analytical models are used as mono-objective function to optimize the device analog/RF performance using Genetic Algorithms (GAs). In comparison with the reported numerical data for Inversion-Mode (IM) DG MOSFET, our optimized performance metrics for JL device exhibit enhancement over the reported data for IM device at the same channel length.

  11. Convergent synthesis of double point modified analogs of 1α,25-dihydroxyvitamin D2 for biological evaluation.

    PubMed

    Nadkarni, Sharmin; Chodyński, Michał; Krajewski, Krzysztof; Cmoch, Piotr; Marcinkowska, Ewa; Brown, Geoffrey; Kutner, Andrzej

    2016-11-01

    There is a long lasting controversy over the biological activity of vitamin D2 as compared to vitamin D3 in terms of maintaining of calcium homeostasis and raising the level of circulating 25-OH-D. To shed more light on this relationship we synthesized 1α,25-dihydroxyvitamin D2, by a novel convergent strategy, to compare this compound directly with the activity of 1α,25-dihydroxyvitamin D3. The same synthetic strategy also provided a series of (5E,7E) geometric isomers of the natural 1α,25-dihydroxyvitamin D2 as well as a series of double point modified analogs of its (24R)-epimer, including C-22 hydroxy derivatives. The structure of the new analogs was determined by (1)H and (13)C NMR as well as by mass spectrometry. The influence of (5E,7E) modification, alone or in combination with additional modifications in the side chain, on the activity profile and metabolic deactivation of analogs of 1α,25-dihydroxyvitamin D2 still remains unknown. (5E,7E) modification in the structure of new analogs of 1α,25-dihydroxyvitamin D2 is expected to give analogs with no influence on calcium level, as was previously obtained for the analogs of 1α,25-dihydroxyvitamin D3. Investigation of the affinities for the vitamin D receptor and cell differentiation, transcriptional and calcium activities of the most active form of vitamin D2 and of (5E,7E) analogs, compared to 1α,25-dihydroxyvitamin D3, is underway in the collaborating laboratories. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Antiproliferative Activity of Double Point Modified Analogs of 1,25-Dihydroxyvitamin D2 Against Human Malignant Melanoma Cell Lines

    PubMed Central

    Piotrowska, Anna; Wierzbicka, Justyna; Nadkarni, Sharmin; Brown, Geoffrey; Kutner, Andrzej; Żmijewski, Michał A.

    2016-01-01

    Vitamin D is a lipid soluble steroid hormone with pleiotropic biological properties, including regulation of cell proliferation, differentiation and apoptosis. As to these desirable anticancer actions, 1,25-dihydroxyvitamins D and analogs have been reported to inhibit the proliferation and to induce differentiation of a wide variety of cancer cell types, including human malignant melanoma. However, there is a need for novel and more efficacious vitamin D analogs, and how best to design such is still an open issue. A series of double point modified (DPM) analogs of 1,25-dihydroxyvitamin D2 (1,25(OH)2D2) induced differentiation of the vitamin D receptor (VDR) positive A375 and VDR negative SK-MEL 188b human malignant melanoma cell lines. Surprisingly, the dose of 1,25(OH)2D2 required to inhibit the proliferation of the A375 melanoma cell line by was several fold lower than that required in the case of 1,25(OH)2D3. To evaluate the impact of the modification in the side chain (additional 22-hydroxyl) and in the A-ring (5,6-trans modification), the regular side-chain of vitamin D2 or D3 was retained in the structure of our analogs. As expected, 5,6-trans modification was advantageous to enhancing the anti-proliferative activity of analogs, but not as a single point modification (SPM). Very unexpectedly, the additional 22-hydroxyl in the side-chain reduced significantly the anti-proliferative activity of both the natural and 5,6-trans series analogs. Finally, an induction of pigmentation in melanoma SK-MEL 188b cells was observed to sensitized cells to the effect of vitamin D analogs. PMID:26760999

  13. Analogs of the double-Reissner-Nordstroem solution in magnetostatics and dilaton gravity: Mathematical description and basic physical properties

    SciTech Connect

    Manko, V. S.; Sanchez-Mondragon, J.; Ruiz, E.

    2009-04-15

    In this paper we consider a magnetic analog of the double-Reissner-Nordstroem solution and construct the corresponding magnetic potential A{sub {phi}} in the explicit form. The behavior of the resulting solution under the Harrison transformation then naturally singles out the asymmetric black diholes--configurations composed of two nonextreme black holes possessing unequal masses, and charges equal in magnitude but opposite in sign - as its most general subclass for which equilibrium of the black-hole constituents can be achieved with the aid of the external magnetic (or electric) field. We also generalize the double-Reissner-Nordstroem solution to dilaton gravity with arbitrary dilaton coupling, yielding the four-dimensional double-Gibbons-Maeda spacetime. The study of some physical properties of the solutions obtained leads, in particular, to very simple formulas for the areas of the horizons and surface gravities.

  14. Magnetotail dynamics under isobaric constraints

    NASA Technical Reports Server (NTRS)

    Birn, Joachim; Schindler, Karl; Janicke, Lutz; Hesse, Michael

    1994-01-01

    Using linear theory and nonlinear MHD simulations, we investigate the resistive and ideal MHD stability of two-dimensional plasma configurations under the isobaric constraint dP/dt = 0, which in ideal MHD is equivalent to conserving the pressure function P = P(A), where A denotes the magnetic flux. This constraint is satisfied for incompressible modes, such as Alfven waves, and for systems undergoing energy losses. The linear stability analysis leads to a Schroedinger equation, which can be investigated by standard quantum mechanics procedures. We present an application to a typical stretched magnetotail configuration. For a one-dimensional sheet equilibrium characteristic properties of tearing instability are rediscovered. However, the maximum growth rate scales with the 1/7 power of the resistivity, which implies much faster growth than for the standard tearing mode (assuming that the resistivity is small). The same basic eigen-mode is found also for weakly two-dimensional equilibria, even in the ideal MHD limit. In this case the growth rate scales with the 1/4 power of the normal magnetic field. The results of the linear stability analysis are confirmed qualitatively by nonlinear dynamic MHD simulations. These results suggest the interesting possibility that substorm onset, or the thinning in the late growth phase, is caused by the release of a thermodynamic constraint without the (immediate) necessity of releasing the ideal MHD constraint. In the nonlinear regime the resistive and ideal developments differ in that the ideal mode does not lead to neutral line formation without the further release of the ideal MHD constraint; instead a thin current sheet forms. The isobaric constraint is critically discussed. Under perhaps more realistic adiabatic conditions the ideal mode appears to be stable but could be driven by external perturbations and thus generate the thin current sheet in the late growth phase, before a nonideal instability sets in.

  15. Sum rule study for double Gamow-Teller states

    NASA Astrophysics Data System (ADS)

    Sagawa, H.; Uesaka, T.

    2016-12-01

    We study the sum rules of double Gamow-Teller (DGT) excitations through double spin-isospin operator (σt-) 2. In general, 2+ states in the grand-daughter nuclei have dominant transition strength in DGT excitations and 0+ states are weak, except in T =1 mother nuclei in which 0+ strength is competitive with 2+ strength. The isospin selection of DGT is also discussed among five possible isospin states in grand-daughter nuclei. A possibility to extract the unit cross section for the DGT transition strength is pointed out in the (σt-) 2 excitation of double isobaric analog state (DIAS) in T =1 nuclei.

  16. Impact of Lateral Straggle on the Analog/RF Performance of Asymmetric Gate Stack Double Gate MOSFET

    NASA Astrophysics Data System (ADS)

    Sivaram, Gollamudi Sai; Chakraborty, Shramana; Das, Rahul; Dasgupta, Arpan; Kundu, Atanu; Sarkar, Chandan K.

    2016-09-01

    This paper presents a systematic comparative study of Analog and RF performances of an underlapped double gate (U-DG) NMOSFET with Gate Stack (GS) for varying straggle lengths. Asymmetric underlap devices (A-U-DG) have been proposed as one of the remedies for reducing Short Channel Effects (SCE's) with the underlap being present towards the source for sub 20 nm devices. However, the Source to Drain (S/D) implant lateral diffusion leads to a variation in the effective underlap length. This paper investigates the impact of variation of straggle length on the Analog and RF parameters of the device. The RF performance is analyzed by considering the intrinsic capacitances (Cgd, Cgs), intrinsic resistances (Rgd, Rgs), transport delay (τm), inductance (Lsd), cutoff frequency (fT), and the maximum frequency of oscillations (fmax). The circuit performance of the devices are also studied. It is seen that the Analog and RF performances of the devices are improved by optimizing the S/D lateral straggle.

  17. Identification of isobaric product ions in electrospray ionization mass spectra of fentanyl using multistage mass spectrometry and deuterium labeling.

    PubMed

    Wichitnithad, Wisut; McManus, Terence J; Callery, Patrick S

    2010-09-15

    Isobaric product ions cannot be differentiated by exact mass determinations, although in some cases deuterium labeling can provide useful structural information for identifying isobaric ions. Proposed fragmentation pathways of fentanyl were investigated by electrospray ionization ion trap mass spectrometry coupled with deuterium labeling experiments and spectra of regiospecific deuterium labeled analogs. The major product ion of fentanyl under tandem mass spectrometry (MS/MS) conditions (m/z 188) was accounted for by a neutral loss of N-phenylpropanamide. 1-(2-Phenylethyl)-1,2,3,6-tetrahydropyridine (1) was proposed as the structure of the product ion. However, further fragmentation (MS(3)) of the fentanyl m/z 188 ion gave product ions that were different from the product ion in the MS/MS fragmentation of synthesized 1, suggesting that the m/z 188 product ion from fentanyl includes an isobaric structure different from the structure of 1. MS/MS fragmentation of fentanyl in deuterium oxide moved one of the isobars to 1 Da higher mass, and left the other isobar unchanged in mass. Multistage mass spectral data from deuterium-labeled proposed isobaric structures provided support for two fragmentation pathways. The results illustrate the utility of multistage mass spectrometry and deuterium labeling in structural assignment of isobaric product ions.

  18. Nanoscale T-shaped Double Gate DG MOSFET: Numerical Investigation for Analog/RF and Digital Performance

    NASA Astrophysics Data System (ADS)

    Kumari, Vandana; Ilango, Aravindan; Saxena, Manoj; Gupta, Mridula

    2016-01-01

    The present work demonstrates the investigation of T-shaped Double Gate MOSFET for analog and digital performance. The 2D analytical modeling scheme is presented using Evanescent Mode Analysis (EMA). The applicability of the proposed model has been verified using ATLAS 3D device simulation. The device exploits peaks in the electric field inside the channel (due to T-shaped gate) for better carrier transport efficiency and subsequently higher drain current and trans-conductance. The impact of dielectric constant of the void layer (due to T-shaped gate) on the electrostatic of the device has been investigated using basic electrical parameters such as: sub-threshold slope, Drain Induced Barrier Lowering DIBL, device gain and Ion/Ioff ratio. The comparative study between T-shaped DG with the conventional DG MOSFET is also presented.

  19. {Delta} isobars and (p,p') reactions

    SciTech Connect

    Sammarruca, F.; Stephenson, E. J.

    2001-09-01

    We explore the role of coupling to {Delta} isobars (in both the N{Delta} and {Delta}{Delta} channels) in medium modifications of the effective NN interaction that drives 200-MeV proton inelastic scattering. A comparison of the predictions to natural-parity (p,p') cross section and analyzing power data show that isobar degrees of freedom in the medium generate overly repulsive effective interactions. Furthermore, this model extension is unable to resolve difficulties observed earlier describing polarization transfer measurements in some high-spin, unnatural-parity (p,p') transitions.

  20. Three-body unitarity with isobars revisited

    DOE PAGES

    Mai, M.; Hu, B.; Döring, M.; ...

    2017-09-08

    The particle exchange model of hadron interactions can be used to describe three-body scattering under the isobar assumption. Here, we start from the 3->3 scattering amplitude for spinless particles, which contains an isobar-spectator scattering amplitude. Using a Bethe-Salpeter Ansatz for the latter, we derive a relativistic three-dimensional scattering equation that manifestly fulfills three-body unitarity and two-body unitarity for the sub-amplitudes. Furthermore, this property holds for energies above breakup and also in the presence of resonances in the sub-amplitudes.

  1. Three-body unitarity with isobars revisited

    NASA Astrophysics Data System (ADS)

    Mai, M.; Hu, B.; Döring, M.; Pilloni, A.; Szczepaniak, A.

    2017-09-01

    The particle exchange model of hadron interactions can be used to describe three-body scattering under the isobar assumption. In this study we start from the 3→ 3 scattering amplitude for spinless particles, which contains an isobar-spectator scattering amplitude. Using a Bethe-Salpeter Ansatz for the latter, we derive a relativistic three-dimensional scattering equation that manifestly fulfills three-body unitarity and two-body unitarity for the sub-amplitudes. This property holds for energies above breakup and also in the presence of resonances in the sub-amplitudes.

  2. Complex energy approaches for calculating isobaric analogue states

    SciTech Connect

    Betan, R. Id; Kruppa, A. T.; Vertse, T.

    2008-10-15

    Parameters of isobaric analog resonance (IAR) are calculated in the framework of the Lane model using different methods. In the standard method, the direct numerical solution of the coupled channel (CC) Lane equations served as a reference for checking two complex energy methods, namely the complex energy shell model (CXSM) and the complex scaling (CS) approaches. The IAR parameters calculated by the CXSM and the CS methods agree with that of the CC results within 1 keV for all partial waves considered. Although the CXSM and the CS methods have similarities, an important difference is that only the CXSM method offers a direct way for studying the configurations of the IAR wave function.

  3. Isochoric and isobaric freezing of fish muscle.

    PubMed

    Năstase, Gabriel; Lyu, Chenang; Ukpai, Gideon; Şerban, Alexandru; Rubinsky, Boris

    2017-04-01

    We have recently shown that, a living organism, which succumbs to freezing to -4 °C in an isobaric thermodynamic system (constant atmospheric pressure), can survive freezing to -4 °C in an isochoric thermodynamic system (constant volume). It is known that the mechanism of cell damage in an isobaric system is the freezing caused increase in extracellular osmolality, and, the consequent cell dehydration. An explanation for the observed survival during isochoric freezing is the thermodynamic modeling supported hypothesis that, in the isochoric frozen solution the extracellular osmolality is comparable to the cell intracellular osmolality. Therefore, cells in the isochoric frozen organism do not dehydrate, and the tissue maintains its morphological integrity. Comparing the histology of: a) fresh fish white muscle, b) fresh muscle frozen to -5 °C in an isobaric system and c) fresh muscle frozen to -5 °C I in an isochoric system, we find convincing evidence of the mechanism of cell dehydration during isobaric freezing. In contrast, the muscle tissue frozen to -5 °C in an isochoric system appears morphologically identical to fresh tissue, with no evidence of dehydration. This is the first experimental evidence in support of the hypothesis that in isochoric freezing there is no cellular dehydration and therefore the morphology of the frozen tissue remains intact. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Isobar separator for radioactive nuclear beams project

    SciTech Connect

    Davids, C.N.; Nolen, J.A.

    1995-08-01

    In order to produce pure beams of radioactive products emanating from the production target/ion source system, both mass and isobar separation is required. A preliminary mass separation with a resolution {triangle}M/M of approximately 10{sup -3} will select the proper mass beam. An isobar separator is needed because the masses of adjacent isobars are usually quite close, especially for beams near stability. In general, a mass resolution of 5 x 10{sup -5} is needed for isobar separation in the A < 120 region, while a resolution of 3 x 10{sup -5} or better is needed for heavier masses. Magnets are used to obtain mass separation. However, in addition to having mass dispersion properties, magnets also have an equal energy dispersion. This means that an energy variation in the beam cannot be distinguished from a mass difference. This is important because ions emerge from the ion source having a small ({approximately} 10{sup -5} - 10{sup -4}) energy spread. In order to make the system respond only to mass differences, it must be made energy dispersion. This is normally accomplished by using a combination of electric and magnetic fields. The most convenient way of doing this is to use an electric deflection following the magnet separator. A preliminary isobar separator which achieves a mass resolution of 2.7 x 10{sup -5} is shown in Figure I-38. It uses two large 60{degrees} bending magnets to obtain a mass dispersion of 140 mm/%, and four electric dipoles with bending angles of 39{degrees} to cancel the energy dispersion. Sextupole and octupole correction elements are used to reduce the geometrical aberrations.

  5. Photophysical and calorimetric studies on the binding of 9-O-substituted analogs of the plant alkaloid berberine to double stranded poly(A).

    PubMed

    Basu, Anirban; Jaisankar, Parasuraman; Kumar, Gopinatha Suresh

    2013-08-05

    This interaction of four novel 9-O-substituted analogs of the plant alkaloid berberine with double stranded poly(A) was studied using a variety of biophysical techniques. Remarkably higher binding of two 9-O-ω-amino alkyl ether analogs compared to the two 9-O-N-aryl/arylalkyl amino carbonyl methyl berberine analogs was observed. Quantum efficiency values suggested that energy was transferred from the adenine base pairs to the analogs on binding. Ferrocyanide quenching and viscosity studies revealed the binding mode to be intercalative for these analogs. Circular dichroism studies showed that these analogs induced significant conformational changes in the secondary structure of ds poly(A). Energetics of the binding suggested that 9-O-N-aryl/arylalkyl amino carbonyl methyl berberines bound very weakly to ds poly(A). The binding of 9-O-ω-amino alkyl ether analogs was entropy dominated with a smaller but favorable enthalpic contribution to the Gibbs energy. Increasing the temperature resulted in weaker binding; the enthalpic contribution increased and the entropic contribution decreased. A small negative heat capacity change with significant enthalpy-entropy compensation established the involvement of multiple weak noncovalent interactions in the binding process.

  6. Quasi-double gate regime to boost UTBB SOI MOSFET performance in analog and sleep transistor applications

    NASA Astrophysics Data System (ADS)

    Kilchytska, V.; Bol, D.; De Vos, J.; Andrieu, F.; Flandre, D.

    2013-06-01

    This paper investigates both electrostatic control improvement and performance enhancement of UTBB SOI MOSFETs obtained in quasi-double-gate (QDG) regime (i.e. simultaneously biasing top- and back-gate (substrate or ground plane) as Vbg = k · Vg) as a strong function of k-multiplication factor, when compared to a standard single-gate mode. Improved performance (in terms of transconductance, drive current and early voltage) in QDG mode combined with lowered DIBL and enhanced gain are of interest for high-precision low-frequency analog applications. QDG mode is demonstrated to allow threshold voltage tuning, subthreshold swing reduction and on-current enhancement without off-state current degradation, thus of interest for digital applications. The unique feature of QDG mode is finally exploited to boost the performances of the sleep transistor in the practical use case of a power-gated processor. About 30% reduction of the leakage in stand-by mode is achieved at nominal Vg with a Vbg of 3 V, which can be generated at marginal area/power overheads with an on-chip charge pump with an architecture proposed in this paper.

  7. A novel vitamin D analog with two double bonds in its side chain. A potent inducer of osteoblastic cell differentiation.

    PubMed

    Mahonen, A; Jääskeläinen, T; Mäenpää, P H

    1996-04-12

    EB 1089 (1 alpha,25-dihydroxy-22,24-diene-24,26,27-trihomovitamin D3) is a novel, synthetic analog of calcitriol, characterized by two extra double bonds in its side chain. It is less potent than calcitriol in its calcemic action, but is an order of magnitude more potent in its antiproliferative action. The aim of this study was to determine the ability of EB 1089 to induce the well-known biological effects of calcitriol in MG-63 human osteosarcoma cells (i.e. by inhibiting cell proliferation and by induction of differentiation). Both calcitriol and EB 1089 significantly decreased cell growth after 2 days in culture. At 5 days, however, Eb 1089 was more potent than the natural hormone in inhibiting the proliferation of MG-63 cells. Potent effects of EB 1089 on cell differentiation were also seen in the stimulation of alkaline phosphatase activity, cellular vitamin D receptor mRNA levels, and medium osteocalcin synthesis. EB 1089 was clearly more effective than calcitriol in stimulating alkaline phosphatase activity and osteocalcin synthesis. In gel shift assays, the binding of vitamin D receptor to the composite AP-1 plus vitamin-D responsive promoter region of the human osteocalcin gene after EB 1089 treatment was stronger and longer-lasting than after calcitriol treatment.

  8. Nearly complete isobar suppression by photodetachment

    NASA Astrophysics Data System (ADS)

    Andersson, P.; Lindahl, A. O.; Hanstorp, D.; Havener, C. C.; Liu, Yun; Liu, Yuan

    2010-01-01

    The efficiency of selective suppression of negative ions by photodetachment in a gas-filled radio frequency quadrupole ion cooler was investigated with a new detection method. A neodymium doped yttrium aluminum garnet laser beam at 1064 nm was used to remove Co- ions in the radio frequency quadrupole cooler and the remaining ions were then probed by photodetachment and neutral particle detection. More than 99.99% suppression of the Co- ions was observed. Under identical conditions, only 20% of a Ni- beam was suppressed. The results demonstrate that this isobar suppression technique can lead to nearly complete elimination of certain isobaric contaminants in negative ion beams, opening up new experimental possibilities in nuclear and atomic research and accelerator mass spectrometry.

  9. Isospin purity in the A=42 isobars

    SciTech Connect

    Orce, J.N.; McKay, C.J.; Choudry, S.N.; Lesher, S.L.; Mynk, M.; Bandyopadhyay, D.; Yates, S.W.; McEllistrem, M.T.; Petkov, P.

    2004-09-13

    The lifetime of the first 2{sub T=1}{sup +} state in 42Sc has been measured as 74(16) fs. This result gives a value for the isoscalar matrix element of M0=6.63(76). From the mirror nuclei, 42Ca and 42Ti, the isoscalar matrix element is given as 7.15(48) W.u., confirming isospin purity in the A=42 isobars.

  10. Isobar Separator for Anions: Current status

    NASA Astrophysics Data System (ADS)

    Alary, Jean-François; Javahery, Gholamreza; Kieser, William; Zhao, Xiao-Lei; Litherland, Albert; Cousins, Lisa; Charles, Christopher

    2015-10-01

    The Isobar Separator for Anions (ISA) is an emerging separation technique of isobars applied first to the selective removal of 36S from 36Cl, achieving a relative suppression ratio of 6 orders of magnitude. Using a radio-frequency quadrupole (RFQ) column incorporating low energy gas cells, this innovative technique enables the use of a wide range of low energy ion-molecule reactions and collisional-induced dissociation processes for suppressing specific atomic of molecular anions with a high degree of selectivity. Other elemental pairs (analyte/isobar) successfully separated at AMS level include Ca/K, Sr/(Y, Zr), Cs/Ba, Hf/W and Pu/U. In view of these initial successes, an effort to develop a version of the ISA that can be used as a robust technique for routine AMS analysis has been undertaken. We will discuss the detailed layout of a practical ISA and the functional requirements that a combined ISA/AMS should meet. These concepts are currently being integrated in a pre-commercial ISA system that will be installed soon at the newly established A.E. Lalonde Laboratory in Ottawa, Canada.

  11. Nuclear matter properties from local chiral interactions with Δ isobar intermediate states

    NASA Astrophysics Data System (ADS)

    Logoteta, Domenico; Bombaci, Ignazio; Kievsky, Alejandro

    2016-12-01

    Using two-nucleon and three-nucleon interactions derived in the framework of chiral perturbation theory (ChPT) with and without the explicit Δ isobar contributions, we calculate the energy per particle of symmetric nuclear matter and pure neutron matter in the framework of the microscopic Brueckner-Hartree-Fock approach. In particular, we present for the first time nuclear matter calculations using the new fully local in coordinate-space two-nucleon interaction at the next-to-next-to-next-to-leading-order (N3LO) of ChPT with Δ isobar intermediate states (N 3 LO Δ ) recently developed by Piarulli et al. [arXiv:1606.06335]. We find that using this N 3 LO Δ potential, supplemented with a local N2LO three-nucleon interaction with explicit Δ isobar degrees of freedom, it is possible to obtain a satisfactory saturation point of symmetric nuclear matter. For this combination of two- and three-nucleon interactions we also calculate the nuclear symmetry energy and we compare our results with the empirical constraints on this quantity obtained using the excitation energies to isobaric analog states in nuclei and using experimental data on the neutron skin thickness of heavy nuclei, finding a very good agreement in all the considered nucleonic density range. In addition, we find that the explicit inclusion of Δ isobars diminishes the strength of the three-nucleon interactions needed to get a good saturation point of symmetric nuclear matter. We also compare the results of our calculations with those obtained by other research groups using chiral nuclear interactions with different many-body methods, finding in many cases a very satisfactory agreement.

  12. Antiproliferative Activity and in Vivo Toxicity of Double-Point Modified Analogs of 1,25-Dihydroxyergocalciferol

    PubMed Central

    Trynda, Justyna; Turlej, Eliza; Milczarek, Magdalena; Pietraszek, Anita; Chodyński, Michał; Kutner, Andrzej; Wietrzyk, Joanna

    2015-01-01

    Analogs of 1,25-dihydroxyergocalciferol, modified in the side-chain and in the A-ring, were tested for their antiproliferative activity against a series of human cancer cell lines in vitro and in vivo toxicity. The proliferation inhibition caused by the analogs was higher than that of the parent compounds, while the toxicity, measured as the serum calcium level, was lower. All analogs were able to induce, in HL-60 and MV4-11 leukemic cells, G0/G1 cell cycle arrest and differentiation expressed as morphological signs typical for monocytes. The analogs also induced the expression of CD11b and/or CD14 cell-differentiation markers. The most potent analogs, PRI-5105, PRI-5106, PRI-5201 and PRI-5202, were also able to induce vitamin D receptor (VDR) protein expression, mainly in the cytoplasmic fraction of HL-60 or MV4-11 cells. The most active analogs were the 19-nor ones with an extended and rigidified side-chain (PRI-5201 and PRI-5202), as in the former analogs PRI-1906 and PRI-1907. Epimerization at C-24 (PRI-5101) or introduction of an additional hydroxyl at C-23 (PRI-5104) reduced the toxicity of the analog with retained antiproliferative activity. PMID:26492238

  13. Systematics of pion double charge exchange

    SciTech Connect

    Gilman, R.A.

    1985-10-01

    Differential cross sections have been measured for pion-induced double-charge-exchange (DCX) reactions leading to double-isobaric-analog states (DIAS) and low-lying nonanalog states in the residual nuclei. A description of the experimental details and data analysis is presented. The experimentally observed systematics of reactions leading to DIAS, to nonanalog ground states, and to low-lying 2 states are described. Lowest-order optical-model calculations of DIAS DCX are compared to the data. Efforts to understand the anomalies by invoking additional reaction-mechanism amplitudes and a higher-order optical potential are described. Calculations of nonanalog DCX reactions leading to J/sup / = 0 states were performed within a distorted-wave impulse-approximation framework. The sensitivities of these calculations to input parameters are discussed. 58 refs., 41 figs., 16 tabs.

  14. Isobar Selective Laser Photodetachment In Trace Element Analysis

    SciTech Connect

    Andersson, P.; Hanstorp, D.; Lindahl, A. O.; Forstner, O.; Wendt, K.

    2009-03-17

    We are investigating the possibility to use laser photodetachment of negative ions as an isobaric selective filter in accelerator mass spectrometry (AMS). If successful, this method can be used to obtain higher sensitivity realized through better selectivity by suppression of molecular and/or elemental isobaric interference in different investigations using ultra rare isotopes in the 10{sup -13} range and below.

  15. QUANTITY: An Isobaric Tag for Quantitative Glycomics

    PubMed Central

    Yang, Shuang; Wang, Meiyao; Chen, Lijun; Yin, Bojiao; Song, Guoqiang; Turko, Illarion V.; Phinney, Karen W.; Betenbaugh, Michael J.; Zhang, Hui; Li, Shuwei

    2015-01-01

    Glycan is an important class of macromolecules that play numerous biological functions. Quantitative glycomics - analysis of glycans at global level - however, is far behind genomics and proteomics owing to technical challenges associated with their chemical properties and structural complexity. As a result, technologies that can facilitate global glycan analysis are highly sought after. Here, we present QUANTITY (Quaternary Amine Containing Isobaric Tag for Glycan), a quantitative approach that can not only enhance detection of glycans by mass spectrometry, but also allow high-throughput glycomic analysis from multiple biological samples. This robust tool enabled us to accomplish glycomic survey of bioengineered Chinese Hamster Ovary (CHO) cells with knock-in/out enzymes involved in protein glycosylation. Our results demonstrated QUANTITY is an invaluable technique for glycan analysis and bioengineering. PMID:26616285

  16. Coulomb energy differences in isobaric multiplets

    SciTech Connect

    Lenzi, S. M.; Farnea, E.; Bazzacco, D.; Brandolini, F.; Lunardi, S.; Mason, P.; Menegazzo, R.; Nespolo, M.; Ur, C. A.; Della Vedova, F.; Marginean, N.; Napoli, D. R.; De Angelis, G.; Axiotis, M.; Gadea, A.; Ionescu-Bujor, M.; Bucurescu, D.; Iordachescu, A.; Bizzeti-Sona, A. M.; Bizzeti, P. G.

    2007-02-12

    By comparing the excitation energies of analogue states in isobaric multiplets, several nuclear structure properties can be studied as a function of the angular momentum up to high spin states. In particular, the mirror nuclei 35Ar and 35Cl show large differences between the excitation energies of analogue negative-parity states at high spin, confirming the important contribution of the relativistic electromagnetic spin-orbit interaction to the Coulomb energy. The single-particle character of the configuration of these states is reproduced with very good accuracy by shell model calculations in the sd and pf shells valence space. In addition, evidence of isospin mixing is deduced from the El transitions linking positive and negative parity states.

  17. Quantum-classical transition for an analog of the double-slit experiment in complex collisions: Dynamical decoherence in quantum many-body systems

    SciTech Connect

    Benet, L.; Chadderton, L. T.; Kun, S. Yu.; Qi Wang

    2007-06-15

    We study coherent superpositions of clockwise and anticlockwise rotating intermediate complexes with overlapping resonances formed in bimolecular chemical reactions. Disintegration of such complexes represents an analog of a famous double-slit experiment. The time for disappearance of the interference fringes is estimated from heuristic arguments related to fingerprints of chaotic dynamics of a classical counterpart of the coherently rotating complex. Validity of this estimate is confirmed numerically for the H+D{sub 2} chemical reaction. Thus we demonstrate the quantum-classical transition in temporal behavior of highly excited quantum many-body systems in the absence of external noise and coupling to an environment.

  18. Isobaric Labeling-Based Relative Quantification in Shotgun Proteomics

    PubMed Central

    2015-01-01

    Mass spectrometry plays a key role in relative quantitative comparisons of proteins in order to understand their functional role in biological systems upon perturbation. In this review, we review studies that examine different aspects of isobaric labeling-based relative quantification for shotgun proteomic analysis. In particular, we focus on different types of isobaric reagents and their reaction chemistry (e.g., amine-, carbonyl-, and sulfhydryl-reactive). Various factors, such as ratio compression, reporter ion dynamic range, and others, cause an underestimation of changes in relative abundance of proteins across samples, undermining the ability of the isobaric labeling approach to be truly quantitative. These factors that affect quantification and the suggested combinations of experimental design and optimal data acquisition methods to increase the precision and accuracy of the measurements will be discussed. Finally, the extended application of isobaric labeling-based approach in hyperplexing strategy, targeted quantification, and phosphopeptide analysis are also examined. PMID:25337643

  19. Double benefit of long-acting somatostatin analogs in a patient with coexistence of acromegaly and ulcerative colitis.

    PubMed

    Yarman, S; Yalın, G Y; Dogansen, S C; Canbaz, B; Tanrıkulu, S; Akyuz, F

    2016-10-01

    Somatostatin analogs control GH/IGF-1 excess in acromegaly. Somatostatin receptors also mediate the complex effects of somatostatin on the gastrointestinal tract and may be defensive in inflammatory bowel diseases, such as ulcerative colitis. We present a patient who showed good response to long-acting octreotide (OCT-LAR) treatment in terms of both acromegaly and ulcerative colitis (UC). A 58-year-old female patient with diagnosis of acromegaly and ulcerative colitis was started on long-acting somatostatin treatment as a first-line treatment for acromegaly as she refused to undergo transsphenoidal surgery. During the follow-up period, a significant amelioration was also observed in the course of ulcerative colitis, and clinical remission of both diseases was achieved uneventfully. Somatostatin appears to be a promising candidate in the treatment of inflammatory bowel diseases. © 2016 John Wiley & Sons Ltd.

  20. Probing the origin of structural stability of single and double stapled p53 peptide analogs bound to MDM2.

    PubMed

    Guo, Zuojun; Streu, Kristina; Krilov, Goran; Mohanty, Udayan

    2014-06-01

    The stabilization of secondary structure is believed to play an important role in the peptide-protein binding interaction. In this study, the α-helical conformation and structural stability of single and double stapled all-hydrocarbon cross-linked p53 peptides when bound and unbound to MDM2 are investigated. We determined the effects of the peptide sequence, the stereochemistry of the cross-linker, the conformation of the double bond in the alkene bridge, and the length of the bridge, to the relative stability of the α-helix structure. The binding affinity calculations by WaterMap provided over one hundred hydration sites in the MDM2 binding pocket where water density is greater than twice that of the bulk, and the relative value of free energy released by displacing these hydration sites. In agreement with the experimental data, potentials of mean force obtained by weighted histogram analysis methods indicated the order of peptides from lowest to highest binding affinity. Our study provides a comprehensive rationalization of the relationship between peptide stapling strategy, the secondary structural stability, and the binding affinity of p53/MDM2 complex. We hope our efforts can help to further the development of a new generation p53/MDM2 inhibitors that can reactivate the function of p53 as tumor suppressor gene.

  1. Isobar giant resonance formation in self-conjugate nuclei

    NASA Astrophysics Data System (ADS)

    Townsend, L. W.; Deutchman, P. A.

    1981-03-01

    The production of isobars with concomitant giant resonance excitations due to peripheral collisions of relativistic heavy ions is investigated. The interaction is described by a modified form of the central term in the one-pion-exchange potential (OPEP) where the projectile ordinary spin operator is replaced by a transition spin operator which describes the creation of an isobar from a nucleon. The scattering is analyzed using time-dependent harmonic perturbation theory to determine the reaction total cross sections. The results obtained, which are valid for reactions involving self-conjugate nuclei, are applied to the specific collison of 2.1 {GeV}/{nucleon}16O projectiles with 12C targets at rest. Cross sections are investigated using two different models for the nuclear spin states. In the first model, the many-body nuclear spin state is reduced, in the spirit of a particle-hole state, to an equivalent two-body state called a particle-core state. In the second model, the many-body spin states are described by unsymmetrized products of individual particle spins. Properties of the spin giant resonance and isobar giant resonance states are investigated. Finally, isobar decay and isobar/pion absorption effects are discussed.

  2. Status of the chiral magnetic effect and collisions of isobars

    NASA Astrophysics Data System (ADS)

    Koch, Volker; Schlichting, Soeren; Skokov, Vladimir; Sorensen, Paul; Thomas, Jim; Voloshin, Sergei; Wang, Gang; Yee, Ho-Ung

    2017-07-01

    In this review, we examine the current theoretical and experimental status of the chiral magnetic effect. We discuss possible future strategies for resolving uncertainties in interpretation including recommendations for theoretical work, recommendations for measurements based on data collected in the past five years, and recommendations for beam use in the coming years of RHIC. We specifically investigate the case for colliding nuclear isobars (nuclei with the same mass but different charge) and find the case compelling. We recommend that a program of nuclear isobar collisions to isolate the chiral magnetic effect from background sources be placed as a high priority item in the strategy for completing the RHIC mission.

  3. High Resolution Charge Exchange Reaction and Analogous {beta}-decay for the Study of Gamow-Teller Transition Strengths

    SciTech Connect

    Fujita, Y.; Rubio, B.

    2007-06-13

    Isospin symmetry is expected for the Tz = {+-}1 {yields} 0 isobaric analogous transitions in isobars with mass number A, where Tz is the z component of isospin T. Assuming this symmetry, strengths of analogous Gamow-Teller (GT) transitions within A = 50 isobars were determined from a high energy-resolution Tz = + 1 {yields} 0, 50Cr(3He,t)50Mn study at 0 deg. in combination with the decay Q-value and lifetime from the Tz = -1 {yields} 0, 50Fe{yields}50Mn {beta} decay. This method can be applied to other pf-shell nuclei and can be used to study GT strengths of astrophysical interest.

  4. A 55-dB SNDR, 2.2-mW double chopper-stabilized analog front-end for a thermopile sensor

    NASA Astrophysics Data System (ADS)

    Chengying, Chen; Xiaoyu, Hu; Jun, Fan; Yong, Hei

    2014-05-01

    A double chopper-stabilized analog front-end (DCS-AFE) circuit for a thermopile sensor is presented, which includes a closed-loop front-end amplifier and a 2nd-order 1 bit quantization sigma—delta modulator. The amplifier with a closed-loop structure ensures the gain stability against the temperature. Moreover, by adopting the chopper-stabilized technique both for the amplifier and 2nd-order 1-bit quantization sigma—delta modulator, the low-frequency 1/f noise and offset is reduced and high resolution is achieved. The AFE is implemented in the SMIC 0.18 μm 1P6M CMOS process. The measurement results show that in a 3.3 V power supply, 1 Hz input frequency and 3KHz clock frequency, the peak signal-to-noise and distortion ratio (SNDR) is 55.4 dB, the effective number of bits (ENOB) is 8.92 bit, and in the range of -20 to 85 degrees, the detection resolution is 0.2 degree.

  5. A novel double carbonyl analog of curcumin induces the apoptosis of human lung cancer H460 cells via the activation of the endoplasmic reticulum stress signaling pathway.

    PubMed

    Ye, Hui; Wei, Xiaoyan; Wang, Zhankun; Zhang, Shanshan; Ren, Jiye; Yao, Song; Shi, Lingyi; Yang, Lizhu; Qiu, Peihong; Wu, Jianzhang; Liang, Guang

    2016-09-01

    Curcumin can inhibit the growth of a variety of cancer cells; however, its poor bioavailability and pharmacokinetic profiles, which are attributed to its instability under physiological conditions, have limited its application in anticancer therapy. In the present study, we screened a double carbonyl analog of curcumin (A17) and analyzed its effects and mechanism of inducing apoptosis in human lung cancer H460 cells. The results showed that A17 not only induced CHOP expression in human lung cancer H460 cells, but also induced the apoptosis of H460 cells in a dose-responsive manner, and this effect was related to corresponding activation of some important components in the endoplasmic reticulum (ER) stress-mediated apoptosis pathway. When CHOP was knocked down by specific siRNA, A17-induced cell apoptosis was attenuated, thereby further demonstrating that the apoptotic pathway is ER stress‑dependent. Our studies demonstrated that A17 has better stability and antitumor activity than curcumin in H460 cells via an ER stress-mediated mechanism. These results imply that A17 could be further explored as a potential anticancer agent for the treatment of human non-small cell lung cancer (NSCLC).

  6. Removal of the samarium isobaric interference from promethium mass analysis

    SciTech Connect

    Shaw, R.W.; Young, J.P.; Smith, D.H.

    1988-02-01

    Resonance ionization mass spectroscopy (RIMS) is used to eliminate isobaric interference when determining the isotopic abundances of an element. In this application, RIMS is applied to the determination of promethium with the removal of samarium interference. In particular, promethium-147 is separated form samarium-147 and samarium-152.

  7. Dissipative Particle Dynamics at Isothermal, Isobaric Conditions Using Shardlow-Like Splitting Algorithms

    DTIC Science & Technology

    2013-09-01

    Dissipative Particle Dynamics at Isothermal, Isobaric Conditions Using Shardlow-Like Splitting Algorithms by John K. Brennan and Martin...5066 ARL-TR-6583 September 2013 Dissipative Particle Dynamics at Isothermal, Isobaric Conditions Using Shardlow-Like Splitting...From - To) May 2010–February 2013 4. TITLE AND SUBTITLE Dissipative Particle Dynamics at Isothermal, Isobaric Conditions Using Shardlow-Like

  8. Lunar Analog

    NASA Technical Reports Server (NTRS)

    Cromwell, Ronita L.

    2009-01-01

    In this viewgraph presentation, a ground-based lunar analog is developed for the return of manned space flight to the Moon. The contents include: 1) Digital Astronaut; 2) Bed Design; 3) Lunar Analog Feasibility Study; 4) Preliminary Data; 5) Pre-pilot Study; 6) Selection of Stockings; 7) Lunar Analog Pilot Study; 8) Bed Design for Lunar Analog Pilot.

  9. Isobar model for kaon photoproduction with spin-7 /2 and -9 /2 nucleon resonances

    NASA Astrophysics Data System (ADS)

    Clymton, S.; Mart, T.

    2017-09-01

    We have investigated the effects of spin-7 /2 and -9 /2 nucleon resonances in the kaon photoproduction process γ p →K+Λ . To this end, the corresponding propagators were derived from the generalized spin projection operators. To remove the lower spin backgrounds in the scattering amplitude, we used the vertex factors obtained from the consistent interaction Lagrangians inspired by Pascalutsa and Vrancx et al. The scattering amplitude was included in our previous isobar model, and the effects of four nucleon resonances with spins 7 /2 and 9 /2 listed by the Particle Data Group were investigated by making use of all available kaon photoproduction data. A significant improvement to our previous model has been observed in all observables, especially in the beam-recoil double-polarization observables Cx, Cz, Ox', and Oz'.

  10. Isobaric inert gas supersaturation: observations, theory, and predictions.

    PubMed

    Collins, J M

    1978-06-01

    An isobaric inert gas supersaturation model incorporating both diffusion and perfusion properties of biological tissue is presented in a form which allows ready comparison with experimental observations. This model requires only measurement of inert gas flux and blood gas solubility in order to evaluate "counterdiffusion potential". Inert gas flux across the skin of Yorkshire piglets anesthetized with pentobarbital was measured for He, Ne, CH4, C2H4, N2O, and SF6. Model predictions based upon these data compare favorably with published reports of isobaric inert gas supersaturation, as well as several previously unpublished observations. The possibility of supersaturation resulting from the use of hydrogen as a breathing gas in a helium environment is also discussed, and extensive animal testing is recommended before potentially dangerous human exposure occurs.

  11. Isobaric Analogue States Studied in Mirrored Fragmentation and Knockout Reactions

    SciTech Connect

    Bentley, M.A.; Pritychenko, B.; Paterson,I.; Brown,J.R.; Taylor,M.J.; Digen,C.Aa.; Adrich,P.; Bazin,D.; Cook.J.M.; Gade,A.; Glasmacher,T.; McDaniel,S.; Ratkiewicz,A.; Siwek,K.; D.Weisshaar,D.; Pritychenko,B.; Lenzi,S.M.

    2010-05-21

    A Gamma-ray spectroscopic study of excited states of isobaric multiplets has been performed in recent years, with a view to gaining a quantitative understanding of energy differences between excited states in terms of a range of Coulomb and other isospin breaking phenomena. Recently, the experimental programme has been augmented by a study of isobaric analogue states of mirror nuclei populated in mirrored fragmentation reactions. In this presentation, recent results on the T = 3/2 analogue states in the T{sub z} = {+-} 3/2 mirror pair {sup 53}Ni/{sup 53}Mn will be summarised. In this work, further strong evidence is found for the need to include an anomalous isospin-breaking two-body matrix element for angular-momentum couplings of J = 2, in addition the expected Coulomb contribution, in order to account for the experimental data.

  12. Isobaric Multiplet Yrast Energies and Isospin Nonconserving Forces

    NASA Astrophysics Data System (ADS)

    Zuker, A. P.; Lenzi, S. M.; Martínez-Pinedo, G.; Poves, A.

    2002-09-01

    The isovector and isotensor energy differences between yrast states of isobaric multiplets in the lower half of the pf region are quantitatively reproduced in a shell model context. The isospin nonconserving nuclear interactions are found to be at least as important as the Coulomb potential. Their isovector and isotensor channels are dominated by J=2 and J=0 pairing terms, respectively. The results are sensitive to the radii of the states, whose evolution along the yrast band can be accurately followed.

  13. Neutrino scattering rates in neutron star matter with {delta} isobars

    SciTech Connect

    Chen Yanjun; Guo Hua; Liu Yuxin

    2007-03-15

    We take the {delta}-isobar degrees of freedom into account in neutron star matter and evaluate their contributions to neutrino scattering cross sections and mean free paths. The neutron star matter is described by means of an effective hadronic model in the relativistic mean-field approximation. It is found that {delta} isobars may be present in neutron stars. The electron chemical potential does not decrease and the neutrino abundance does not increase with the increase of the density when neutrinos are trapped in the matter with {delta} isobars. The large vector coupling constant between the {delta}{sup -} and neutrino and the high spin of the {delta} influence significantly the neutrino scattering cross section and lead the contribution of the {delta}{sup -} to the dominance of the scattering rates. In neutrino-trapped case, the presence of {delta}s causes the neutrino mean free path to decrease drastically compared to that in the matter in which baryons are only nucleons.

  14. TITAN's multiple-reflection time-of-flight isobar separator

    NASA Astrophysics Data System (ADS)

    Reiter, Moritz Pascal; Titan Collaboration

    2016-09-01

    At the ISAC facility located at TRIUMF exotic nuclei are produced by the ISOL method. Exotic nuclei are separated by a magnetic separator and transported to TRIUMF's Ion Trap for Atomic and Nuclear science (TITAN). TITAN is a system of multiple ion traps for high precision mass measurements and in-trap decay spectroscopy. Although ISAC can deliver some of the highest yields for even many of the most exotic species many measurements suffer from a strong isobaric background. This background often prevents the high precision measurement of the species of interest. To overcome this limitation an additional isobar separator based on the Multiple-Reflection Time-Of-Flight Mass Spectrometry (MR-TOF-MS) technique has been developed for TITAN. Mass selection is achieved using dynamic re-trapping of the species of interest after a time-of-flight analysis in an electrostatic isochronous reflector system. Additionally the MR-TOF-MS will, on its own, enable mass measurements of very short-lived nuclides that are weakly produced. Being able to measure all isobars of a given mass number at the same time the MR-TOF-MS can be used for beam diagnostics or determination of beam compositions. Results from the offline commissioning showing mass resolving power and separation power will be presented.

  15. Analogy, Dialectics and Lifelong Learning.

    ERIC Educational Resources Information Center

    Bailey, Ted

    2003-01-01

    Compares analogies and dialectics, discussing limitations of the Hegelian/Marxian dialectical form in adult education. Proposes the more holistic approach of Vico, a double dialectic that connects social and individual relationships, knowledge, and experience. Demonstrates a dialectical learning exchange that uses an analogy trigger. (SK)

  16. Improvement of non-isobaric model for shock ignition

    NASA Astrophysics Data System (ADS)

    Farahbod, Amir Hossein; Abolfazl Ghasemi, Seyed; Jafar Jafari, Mohammad; Rezaei, Somayeh; Sobhanian, Samad

    2014-10-01

    In this paper, improved relations of total fuel energy, fuel gain, hot-spot radius and total areal density in a non-isobaric model of fuel assembly have been derived and compared with the numerical results of [J. Schmitt, J.W. Bates, S.P. Obenschain, S.T. Zalesak, D.E. Fyfe, Phys. Plasmas 17, 042701 (2010); S. Atzeni, A. Marocchino, A. Schiavi, G. Schurtz, New J. Phys. 15, 045004 (2013)] and several simulations performed by MULTI-1D radiation hydrodynamic code for shock ignition scenario. Our calculations indicate that the approximations made by [M.D. Rosen, J.D. Lindl, A.R. Thiessen, LLNL Laser Program Annual Report, UCRL-50021-83, pp. 3-5 (1983); J. Schmitt, J.W. Bates, S.P. Obenschain, S.T. Zalesak, D.E. Fyfe, Phys. Plasmas 17, 042701 (2010)] for the calculation of burn-up fraction are not accurate enough to give results consistent with simulations. Therefore, we have introduced more appropriate approximations for the burn-up fraction and total areal density of the fuel that are in more agreement with simulation results of shock ignition. Meanwhile, it is shown that the related formulas of the non-isobaric model for total fuel energy, fuel gain and also hot-spot radius cannot determine the model parameters independently, but improved model choose a better selection and less restrictions on determination of the parameters for the non-isobaric model. Such derivations can be used in theoretical studies of the ignition conditions and burn-up fraction of the fuel in shock ignition scenario.

  17. Isobaric Labeling and Data Normalization without Requiring Protein Quantitation

    PubMed Central

    Kim, Phillip D.; Patel, Bhavinkumar B.; Yeung, Anthony T.

    2012-01-01

    Isobaric multiplexed quantitative proteomics can complement high-resolution sample isolation techniques. Here, we report a simple workflow exponentially modified protein abundance index (emPAI)-MW deconvolution (EMMOL) for normalizing isobaric reporter ratios within and between experiments, where small or unknown amounts of protein are used. EMMOL deconvolutes the isobaric tags for relative and absolute quantification (iTRAQ) data to yield the quantity of each protein of each sample in the pool, a new approach that enables the comparison of many samples without including a channel of reference standard. Moreover, EMMOL allows using a sufficient quantity of control sample to facilitate the peptide fractionation (isoelectric-focusing was used in this report), and mass spectrometry MS/MS sequencing yet relies on the broad dynamic range of iTRAQ quantitation to compare relative protein abundance. We demonstrated EMMOL by comparing four pooled samples with 20-fold range differences in protein abundance and performed data normalization without using prior knowledge of the amounts of proteins in each sample, simulating an iTRAQ experiment without protein quantitation prior to labeling. We used emPAI,1 the target protein MW, and the iTRAQ reporter ratios to calculate the amount of each protein in each of the four channels. Importantly, the EMMOL-delineated proteomes from separate iTRAQ experiments can be assorted for comparison without using a reference sample. We observed no compression of expression in iTRAQ ratios over a 20-fold range for all protein abundances. To complement this ability to analyze minute samples, we report an optimized iTRAQ labeling protocol for using 5 μg protein as the starting material. PMID:22468137

  18. Laser ion source for isobaric heavy ion collider experiment.

    PubMed

    Kanesue, T; Kumaki, M; Ikeda, S; Okamura, M

    2016-02-01

    Heavy-ion collider experiment in isobaric system is under investigation at Relativistic Heavy Ion Collider. For this experiment, ion source is required to maximize the abundance of the intended isotope. The candidate of the experiment is (96)Ru + (96)Zr. Since the natural abundance of particular isotope is low and composition of isotope from ion source depends on the composites of the target, an isotope enriched material may be needed as a target. We studied the performance of the laser ion source required for the experiment for Zr ions.

  19. Laser ion source for isobaric heavy ion collider experiment

    SciTech Connect

    Kanesue, T. Okamura, M.; Kumaki, M.; Ikeda, S.

    2016-02-15

    Heavy-ion collider experiment in isobaric system is under investigation at Relativistic Heavy Ion Collider. For this experiment, ion source is required to maximize the abundance of the intended isotope. The candidate of the experiment is {sup 96}Ru + {sup 96}Zr. Since the natural abundance of particular isotope is low and composition of isotope from ion source depends on the composites of the target, an isotope enriched material may be needed as a target. We studied the performance of the laser ion source required for the experiment for Zr ions.

  20. Isobaric multiplet mass equation in the A =31 ,T =3 /2 quartets

    NASA Astrophysics Data System (ADS)

    Bennett, M. B.; Wrede, C.; Brown, B. A.; Liddick, S. N.; Pérez-Loureiro, D.; Bardayan, D. W.; Chen, A. A.; Chipps, K. A.; Fry, C.; Glassman, B. E.; Langer, C.; Larson, N. R.; McNeice, E. I.; Meisel, Z.; Ong, W.; O'Malley, P. D.; Pain, S. D.; Prokop, C. J.; Schwartz, S. B.; Suchyta, S.; Thompson, P.; Walters, M.; Xu, X.

    2016-06-01

    Background: The observed mass excesses of analog nuclear states with the same mass number A and isospin T can be used to test the isobaric multiplet mass equation (IMME), which has, in most cases, been validated to a high degree of precision. A recent measurement [Kankainen et al., Phys. Rev. C 93, 041304(R) (2016), 10.1103/PhysRevC.93.041304] of the ground-state mass of 31Cl led to a substantial breakdown of the IMME for the lowest A =31 ,T =3 /2 quartet. The second-lowest A =31 ,T =3 /2 quartet is not complete, due to uncertainties associated with the identity of the 31S member state. Purpose: Our goal is to populate the two lowest T =3 /2 states in 31S and use the data to investigate the influence of isospin mixing on tests of the IMME in the two lowest A =31 ,T =3 /2 quartets. Methods: Using a fast 31Cl beam implanted into a plastic scintillator and a high-purity Ge γ -ray detection array, γ rays from the 31Cl(β γ )31S sequence were measured. Shell-model calculations using USDB and the recently-developed USDE interactions were performed for comparison. Results: Isospin mixing between the 31S isobaric analog state (IAS) at 6279.0(6) keV and a nearby state at 6390.2(7) keV was observed. The second T =3 /2 state in 31S was observed at Ex=7050.0 (8 ) keV. Calculations using both USDB and USDE predict a triplet of isospin-mixed states, including the lowest T =3 /2 state in 31P, mirroring the observed mixing in 31S, and two isospin-mixed triplets including the second-lowest T =3 /2 states in both 31S and 31P. Conclusions: Isospin mixing in 31S does not by itself explain the IMME breakdown in the lowest quartet, but it likely points to similar isospin mixing in the mirror nucleus 31P, which would result in a perturbation of the 31P IAS energy. USDB and USDE calculations both predict candidate 31P states responsible for the mixing in the energy region slightly above Ex=6400 keV. The second quartet has been completed thanks to the identification of the second 31S T

  1. Small parametric model of the precomputation of meteorological fields on the basis of complete equations and its energetic analogs

    NASA Technical Reports Server (NTRS)

    Borisenkov, Y. P.

    1974-01-01

    A small parametric, nonadiabatic model for precomputation of meteorological fields on the basis of complete equations, along with its energetic analogs is described. The model incorporates integral characteristics of the components of the wind speed and the analogous functions of the total fluxes of the ocean, and uses a Cartesian isobaric system of coordinates.

  2. Deuterium isobaric amine-reactive tags for quantitative proteomics.

    PubMed

    Zhang, Junxiang; Wang, Yan; Li, Shuwei

    2010-09-15

    This paper demonstrates the applications of a novel isobaric reagent, named deuterium ((2)H) isobaric amine-reactive tag (DiART), for quantitative proteomics. Peptides labeled with DiART were analyzed using an electrospray ionization (ESI)-based LTQ-Orbitrap mass spectrometer. Our data showed that (2)H-associated isotope effects, such as partial loss of (2)H labels during tandem mass spectrometry (MS/MS) and (2)H-related chromatographic shift, were either not observed or negligible. With the use of a hybrid collision-induced dissociation (CID)-higher energy C-trap dissociation (HCD) acquisition method, we were able to identify DiART-labeled peptides with high confidence and quantify them with high accuracy. Furthermore, we adopted a hybrid electron-transfer dissociation (ETD)-HCD acquisition protocol and developed a novel data analysis approach to measure phosphorylation of peptides. Our results showed DiART had excellent performance on LTQ-Orbitrap instruments and provided a cost-effective technique for large-scale quantitative proteomics measurements.

  3. Isobaric (gasless) laparoscopic liver and kidney biopsy in standing steers.

    PubMed

    Chiesa, O Alberto; von Bredow, Jurgen; Li, Hui; Smith, Michelle

    2009-01-01

    The purpose of the current study was to investigate the suitability of an isobaric laparoscopic procedure, using a single port, for obtaining serial kidney and liver biopsy samples from standing steers. The samples were used in support of a pharmacokinetic tissue-fluid correlation study. Laparoscopic access was performed 3 times in each of 8 healthy Holstein steers, alternating from the right side to the left side and then to the right side again. The surgery was performed in standing stocks after the animals were given 3 doses of sulfadimethoxine sulfate intravenously and fasted for at least 18 h. Sedation and analgesia were achieved with acepromazine and xylazine. Lidocaine 2% was injected at the center of the paralumbar fossa (left or right), and an incision was made for introduction of a trocar-cannula assembly. Room air was allowed to enter the abdomen through the cannula at the time of insertion. Once the peritoneal cavity was reached, an operating endoscope was inserted. No pressurized insufflation was performed. A biopsy forceps was introduced into the operating channel of the endoscope to obtain a 100-mg kidney or liver sample. No complications were encountered. The 24 laparoscopic procedures provided 24 kidney and 16 liver samples. The results suggest that the isobaric (gasless) single-port laparoscopic technique is feasible for kidney and liver biopsy on standing steers. The procedure can be performed in a reliable and efficient manner in the sedated standing bovine.

  4. An objective isobaric/isentropic technique for upper air analysis

    NASA Technical Reports Server (NTRS)

    Mancuso, R. L.; Endlich, R. M.; Ehernberger, L. J.

    1981-01-01

    An objective meteorological analysis technique is presented whereby both horizontal and vertical upper air analyses are performed. The process used to interpolate grid-point values from the upper-air station data is the same as for grid points on both an isobaric surface and a vertical cross-sectional plane. The nearby data surrounding each grid point are used in the interpolation by means of an anisotropic weighting scheme, which is described. The interpolation for a grid-point potential temperature is performed isobarically; whereas wind, mixing-ratio, and pressure height values are interpolated from data that lie on the isentropic surface that passes through the grid point. Two versions (A and B) of the technique are evaluated by qualitatively comparing computer analyses with subjective handdrawn analyses. The objective products of version A generally have fair correspondence with the subjective analyses and with the station data, and depicted the structure of the upper fronts, tropopauses, and jet streams fairly well. The version B objective products correspond more closely to the subjective analyses, and show the same strong gradients across the upper front with only minor smoothing.

  5. An objective isobaric/isentropic technique for upper air analysis

    NASA Technical Reports Server (NTRS)

    Mancuso, R. L.; Endlich, R. M.; Ehernberger, L. J.

    1981-01-01

    An objective meteorological analysis technique is presented whereby both horizontal and vertical upper air analyses are performed. The process used to interpolate grid-point values from the upper-air station data is the same as for grid points on both an isobaric surface and a vertical cross-sectional plane. The nearby data surrounding each grid point are used in the interpolation by means of an anisotropic weighting scheme, which is described. The interpolation for a grid-point potential temperature is performed isobarically; whereas wind, mixing-ratio, and pressure height values are interpolated from data that lie on the isentropic surface that passes through the grid point. Two versions (A and B) of the technique are evaluated by qualitatively comparing computer analyses with subjective handdrawn analyses. The objective products of version A generally have fair correspondence with the subjective analyses and with the station data, and depicted the structure of the upper fronts, tropopauses, and jet streams fairly well. The version B objective products correspond more closely to the subjective analyses, and show the same strong gradients across the upper front with only minor smoothing.

  6. Nested sampling of isobaric phase space for the direct evaluation of the isothermal-isobaric partition function of atomic systems

    SciTech Connect

    Wilson, Blake A.; Nielsen, Steven O.; Gelb, Lev D.

    2015-10-21

    Nested Sampling (NS) is a powerful athermal statistical mechanical sampling technique that directly calculates the partition function, and hence gives access to all thermodynamic quantities in absolute terms, including absolute free energies and absolute entropies. NS has been used predominately to compute the canonical (NVT) partition function. Although NS has recently been used to obtain the isothermal-isobaric (NPT) partition function of the hard sphere model, a general approach to the computation of the NPT partition function has yet to be developed. Here, we describe an isobaric NS (IBNS) method which allows for the computation of the NPT partition function of any atomic system. We demonstrate IBNS on two finite Lennard-Jones systems and confirm the results through comparison to parallel tempering Monte Carlo. Temperature-entropy plots are constructed as well as a simple pressure-temperature phase diagram for each system. We further demonstrate IBNS by computing part of the pressure-temperature phase diagram of a Lennard-Jones system under periodic boundary conditions.

  7. Isobar Model for Photoproduction of K+Σ0 and K0Σ+ on the Proton

    NASA Astrophysics Data System (ADS)

    Mart, T.

    2007-01-01

    Kaon photoproductions on the proton γp → K+Σ0 and γp → K0Σ+ have been simultaneously analyzed by using isobar models and new SAPHIR data. The result shows that isobar models such as KAON MAID require more resonances in order to explain the data.

  8. Rapid cooling of neutron stars by hyperons and Delta isobars

    NASA Technical Reports Server (NTRS)

    Prakash, Madappa; Prakash, Manju; Lattimer, James M.; Pethick, C. J.

    1992-01-01

    Direct Urca processes with hyperons and/or nucleon isobars can occur in dense matter as long as the concentration of Lambda hyperons exceeds a critical value that is less than 3 percent and is typically about 0.1 percent. The neutrino luminosities from the hyperon Urca processes are about 5-100 times less than the typical luminosity from the nucleon direct Urca process, if the latter process is not forbidden, but they are larger than those expected from other sources. These direct Urca processes provide avenues for rapid cooling of neutron stars which invoke neither exotic states nor the large proton fraction (of order 0.11-0.15) required for the nucleon direct Urca process.

  9. The isobaric multiplet mass equation for A≤71 revisited

    NASA Astrophysics Data System (ADS)

    Lam, Yi Hua; Blank, Bertram; Smirnova, Nadezda A.; Bueb, Jean Bernard; Antony, Maria Susai

    2013-11-01

    Accurate mass determination of short-lived nuclides by Penning-trap spectrometers and progress in the spectroscopy of proton-rich nuclei have triggered renewed interest in the isobaric multiplet mass equation (IMME). The energy levels of the members of T=1/2,1,3/2, and 2 multiplets and the coefficients of the IMME are tabulated for A≤71. The new compilation is based on the most recent mass evaluation (AME2011) and it includes the experimental results on energies of the states evaluated up to end of 2011. Taking into account the error bars, a significant deviation from the quadratic form of the IMME for the A=9,35 quartets and the A=32 quintet is observed.

  10. The isobaric multiplet mass equation for A≤71 revisited

    SciTech Connect

    Lam, Yi Hua; Blank, Bertram; Smirnova, Nadezda A.; Bueb, Jean Bernard; Antony, Maria Susai

    2013-11-15

    Accurate mass determination of short-lived nuclides by Penning-trap spectrometers and progress in the spectroscopy of proton-rich nuclei have triggered renewed interest in the isobaric multiplet mass equation (IMME). The energy levels of the members of T=1/2,1,3/2, and 2 multiplets and the coefficients of the IMME are tabulated for A≤71. The new compilation is based on the most recent mass evaluation (AME2011) and it includes the experimental results on energies of the states evaluated up to end of 2011. Taking into account the error bars, a significant deviation from the quadratic form of the IMME for the A=9,35 quartets and the A=32 quintet is observed.

  11. Rapid cooling of neutron stars by hyperons and Delta isobars

    NASA Technical Reports Server (NTRS)

    Prakash, Madappa; Prakash, Manju; Lattimer, James M.; Pethick, C. J.

    1992-01-01

    Direct Urca processes with hyperons and/or nucleon isobars can occur in dense matter as long as the concentration of Lambda hyperons exceeds a critical value that is less than 3 percent and is typically about 0.1 percent. The neutrino luminosities from the hyperon Urca processes are about 5-100 times less than the typical luminosity from the nucleon direct Urca process, if the latter process is not forbidden, but they are larger than those expected from other sources. These direct Urca processes provide avenues for rapid cooling of neutron stars which invoke neither exotic states nor the large proton fraction (of order 0.11-0.15) required for the nucleon direct Urca process.

  12. Mapping Isobaric Aging onto the Equilibrium Phase Diagram

    NASA Astrophysics Data System (ADS)

    Niss, Kristine

    2017-09-01

    The linear volume relaxation and the nonlinear volume aging of a glass-forming liquid are measured, directly compared, and used to extract the out-of-equilibrium relaxation time. This opens a window to investigate how the relaxation time depends on temperature, structure, and volume in parts of phase space that are not accessed by the equilibrium liquid. It is found that the temperature dependence of relaxation time is non-Arrhenius even in the isostructural case—challenging the Adam-Gibbs entropy model. Based on the presented data and the idea that aging happens through quasiequilibrium states, we suggest a mapping of the out-of-equilibrium states during isobaric aging to the equilibrium phase diagram. This mapping implies the existence of isostructural lines in the equilibrium phase diagram. The relaxation time is found to depend on the bath temperature, density, and a just single structural parameter, referred to as an effective temperature.

  13. Identification of isobaric amino-sulfonamides without prior separation.

    PubMed

    Barry, Samantha J; Wolff, Jean-Claude

    2012-02-29

    Direct analysis mass spectrometry (DAMS) techniques offer increased speed of analysis without the need for sample preparation or prior separation. A feature of these techniques is that all ionisable species will typically be analysed at the same time which makes the ability to distinguish between isobaric compounds increasingly important. Investigations have been carried out to distinguish isomeric compounds by mass spectrometry only, without the use of any separation technique, in order to further understand the capabilities of DAMS techniques. The work focused on commercially available isomeric amino-sulfonamides, i.e. sulfalene, sulfameter, sulfamethoxypyridazine, sulfamonomethoxine, sulfadoxine, sulfadimethoxine, sulfisomidine, sulfamethazine, sulfamerazine, sulfaperine, sulfadiazine and sulfapyrazine. All the isomeric compounds investigated could be distinguished from each other based on their tandem mass (MS/MS) spectrum or failing that, based on their MS(3) spectrum. Common fragmentation patterns/pathways were observed for groups of the sulfonamides and a rationale for the fragmentations observed is proposed. For the sulfonamides which contain a methoxy group on the pyrimidinyl, pyridazynil, or pyrazinyl ring, the fragmentation-directing feature is the positioning of the methoxy group in the ortho position of the ring with respect to the sulfonamide bond. The presence of an ortho substituent precludes the formation of the product ion resulting from the loss of aniline. This work has demonstrated the usefulness of MS(n) fragmentation data in identifying and distinguishing isobaric structural isomers without the need for separation by high-performance liquid chromatography (HPLC), allowing the identification of compounds by DAMS techniques. This work has also highlighted patterns in the product ion data which has led to a postulation of how the protonation preference of a molecule can affect the product ions observed and how the presence of ortho substituents

  14. Hard breakup of the deuteron into two {Delta} isobars

    SciTech Connect

    Granados, Carlos G.; Sargsian, Misak M.

    2011-05-15

    We study high-energy photodisintegration of the deuteron into two {Delta} isobars at large center of mass angles within the QCD hard rescattering model (HRM). According to the HRM, the process develops in three main steps: the photon knocks a quark from one of the nucleons in the deuteron; the struck quark rescatters off a quark from the other nucleon sharing the high energy of the photon; then the energetic quarks recombine into two outgoing baryons which have large transverse momenta. Within the HRM, the cross section is expressed through the amplitude of pn{yields}{Delta}{Delta} scattering which we evaluated based on the quark-interchange model of hard hadronic scattering. Calculations show that the angular distribution and the strength of the photodisintegration is mainly determined by the properties of the pn{yields}{Delta}{Delta} scattering. We predict that the cross section of the deuteron breakup to {Delta}{sup ++}{Delta}{sup -} is 4-5 times larger than that of the breakup to the {Delta}{sup +}{Delta}{sup 0} channel. Also, the angular distributions for these two channels are markedly different. These can be compared with the predictions based on the assumption that two hard {Delta} isobars are the result of the disintegration of the preexisting {Delta}{Delta} components of the deuteron wave function. In this case, one expects the angular distributions and cross sections of the breakup in both {Delta}{sup ++}{Delta}{sup -} and {Delta}{sup +}{Delta}{sup 0} channels to be similar.

  15. Vectorial transport of nucleoside analogs from the apical to the basolateral membrane in double-transfected cells expressing the human concentrative nucleoside transporter hCNT3 and the export pump ABCC4.

    PubMed

    Rius, Maria; Keller, Daniela; Brom, Manuela; Hummel-Eisenbeiss, Johanna; Lyko, Frank; Keppler, Dietrich

    2010-07-01

    The identification of the transport proteins responsible for the uptake and the efflux of nucleosides and their metabolites enables the characterization of their vectorial transport and a better understanding of their absorption, distribution, and elimination. Human concentrative nucleoside transporters (hCNTs/SLC28A) are known to mediate the transport of natural nucleosides and some nucleoside analogs into cells in a sodium-dependent and unidirectional manner. On the other hand, several human multidrug resistance proteins [human ATP-binding cassette transporter, subfamily C (ABCC)] cause resistance against nucleoside analogs and mediate transport of phosphorylated nucleoside derivatives out of the cells in an ATP-dependent manner. For the integrated analysis of uptake and efflux of these compounds, we established a double-transfected Madin-Darby canine kidney (MDCK) II cell line stably expressing the human uptake transporter hCNT3 in the apical membrane and the human efflux pump ABCC4 in the basolateral membrane. The direction of transport was from the apical to the basolateral compartment, which is in line with the unidirectional transport and the localization of both recombinant proteins in the MDCKII cells. Recombinant hCNT3 mediated the transport of several known nucleoside substrates, and we identified 5-azacytidine as a new substrate for hCNT3. It is of interest that coexpression of both transporters was confirmed in pancreatic adenocarcinomas, which represent an important clinical indication for the therapeutic use of nucleoside analogs. Thus, our results establish a novel cell system for studies on the vectorial transport of nucleosides and their analogs from the apical to the basolateral compartment. The results contribute to a better understanding of the cellular transport characteristics of nucleoside drugs.

  16. Piscidin-1-analogs with double L- and D-lysine residues exhibited different conformations in lipopolysaccharide but comparable anti-endotoxin activities

    PubMed Central

    Kumar, Amit; Mahajan, Mukesh; Awasthi, Bhanupriya; Tandon, Anshika; Harioudh, Munesh Kumar; Shree, Sonal; Singh, Pratiksha; Shukla, Praveen Kumar; Ramachandran, Ravishankar; Mitra, Kalyan; Bhattacharjya, Surajit; Ghosh, Jimut Kanti

    2017-01-01

    To become clinically effective, antimicrobial peptides (AMPs) should be non-cytotoxic to host cells. Piscidins are a group of fish-derived AMPs with potent antimicrobial and antiendotoxin activities but limited by extreme cytotoxicity. We conjectured that introduction of cationic residue(s) at the interface of polar and non-polar faces of piscidins may control their insertion into hydrophobic mammalian cell membrane and thereby reducing cytotoxicity. We have designed several novel analogs of piscidin-1 by substituting threonine residue(s) with L and D-lysine residue(s). L/D-lysine-substituted analogs showed significantly reduced cytotoxicity but exhibited either higher or comparable antibacterial activity akin to piscidin-1. Piscidin-1-analogs demonstrated higher efficacy than piscidin-1 in inhibiting lipopolysaccharide (LPS)-induced pro-inflammatory responses in THP-1 cells. T15,21K-piscidin-1 (0.5 mg/Kg) and T15,21dK-piscidin-1 (1.0 mg/Kg) demonstrated 100% survival of LPS (12.0 mg/Kg)-administered mice. High resolution NMR studies revealed that both piscidin-1 and T15,21K-piscidin-1 adopted helical structures, with latter showing a shorter helix, higher amphipathicity and cationic residues placed at optimal distances to form ionic/hydrogen bond with lipid A of LPS. Remarkably, T15,21dK-piscidin-1 showed a helix-loop-helix structure in LPS and its interactions with LPS could be sustained by the distance of separation of side chains of R7 and D-Lys-15 which is close to the inter-phosphate distance of lipid A. PMID:28051162

  17. In Alzheimer’s Disease, 6-Month Treatment with GLP-1 Analog Prevents Decline of Brain Glucose Metabolism: Randomized, Placebo-Controlled, Double-Blind Clinical Trial

    PubMed Central

    Gejl, Michael; Gjedde, Albert; Egefjord, Lærke; Møller, Arne; Hansen, Søren B.; Vang, Kim; Rodell, Anders; Brændgaard, Hans; Gottrup, Hanne; Schacht, Anna; Møller, Niels; Brock, Birgitte; Rungby, Jørgen

    2016-01-01

    In animal models, the incretin hormone GLP-1 affects Alzheimer’s disease (AD). We hypothesized that treatment with GLP-1 or an analog of GLP-1 would prevent accumulation of Aβ and raise, or prevent decline of, glucose metabolism (CMRglc) in AD. In this 26-week trial, we randomized 38 patients with AD to treatment with the GLP-1 analog liraglutide (n = 18), or placebo (n = 20). We measured Aβ load in brain with tracer [11C]PIB (PIB), CMRglc with [18F]FDG (FDG), and cognition with the WMS-IV scale (ClinicalTrials.gov NCT01469351). The PIB binding increased significantly in temporal lobe in placebo and treatment patients (both P = 0.04), and in occipital lobe in treatment patients (P = 0.04). Regional and global increases of PIB retention did not differ between the groups (P ≥ 0.38). In placebo treated patients CMRglc declined in all regions, significantly so by the following means in precuneus (P = 0.009, 3.2 μmol/hg/min, 95% CI: 5.45; 0.92), and in parietal (P = 0.04, 2.1 μmol/hg/min, 95% CI: 4.21; 0.081), temporal (P = 0.046, 1.54 μmol/hg/min, 95% CI: 3.05; 0.030), and occipital (P = 0.009, 2.10 μmol/hg/min, 95% CI: 3.61; 0.59) lobes, and in cerebellum (P = 0.04, 1.54 μmol/hg/min, 95% CI: 3.01; 0.064). In contrast, the GLP-1 analog treatment caused a numerical but insignificant increase of CMRglc after 6 months. Cognitive scores did not change. We conclude that the GLP-1 analog treatment prevented the decline of CMRglc that signifies cognitive impairment, synaptic dysfunction, and disease evolution. We draw no firm conclusions from the Aβ load or cognition measures, for which the study was underpowered. PMID:27252647

  18. Analog earthquakes

    SciTech Connect

    Hofmann, R.B.

    1995-09-01

    Analogs are used to understand complex or poorly understood phenomena for which little data may be available at the actual repository site. Earthquakes are complex phenomena, and they can have a large number of effects on the natural system, as well as on engineered structures. Instrumental data close to the source of large earthquakes are rarely obtained. The rare events for which measurements are available may be used, with modfications, as analogs for potential large earthquakes at sites where no earthquake data are available. In the following, several examples of nuclear reactor and liquified natural gas facility siting are discussed. A potential use of analog earthquakes is proposed for a high-level nuclear waste (HLW) repository.

  19. Testing the chiral magnetic effect with isobaric collisions

    NASA Astrophysics Data System (ADS)

    Deng, Wei-Tian; Huang, Xu-Guang; Ma, Guo-Liang; Wang, Gang

    2016-10-01

    The quark-gluon matter produced in relativistic heavy-ion collisions may contain local domains in which parity (P ) and combined charge conjugation and parity (C P ) symmetries are not preserved. When coupled with an external magnetic field, such P - and C P -odd domains will generate electric currents along the magnetic field—a phenomenon called the chiral magnetic effect (CME). Recently, the STAR Collaboration at the BNL Relativistic Heavy Ion Collider (RHIC) and the ALICE Collaboration at the CERN Large Hadron Collider (LHC) released data of charge-dependent azimuthal-angle correlators with features consistent with the CME expectation. However, the experimental observable is contaminated with significant background contributions from elliptic-flow-driven effects, which makes the interpretation of the data ambiguous. We show that the collisions of isobaric nuclei, Ru9644+Ru9644 and Zr9640+Zr9640, provide an ideal tool to disentangle the CME signal from the background effects. Our simulation demonstrates that the two collision types at √{sN N}=200 GeV have more than 10 % difference in the CME signal and less than 2 % difference in the elliptic-flow-driven backgrounds for the centrality range of 20-60%.

  20. Compact high resolution isobar separator for study of exotic decays

    NASA Astrophysics Data System (ADS)

    Shchepunov, V.; Piechaczek, A.; Carter, H. K.; Batchelder, J. C.; Zganjar, E. F.

    2009-05-01

    A compact isobar separator, based on the Multi-Pass-Time-of-Flight (MTOF) principle, is developed. A mass resolving power (MRP) of 110,000 (FWHM) is achieved as spectrometer with a transmission of 50 - 80%. The transverse beam acceptance and the energy acceptance are 42 π mm mrad and about ± 2.5%. Operated as a separator, molecules of N2 and CO with δM/M = 1/2500 or 10.433 MeV were separated with a Bradbury Nielsen gate. In that mode of operation, the MRP (FWHM) is about 40,000 after 120 laps. To inject radioactive ion beams into the separator, and to further improve its MRP, cooler and buncher RF quadrupoles were designed^1 and tested. A bunch width of 30 ns at 1% of the peak height (FWHM = 9 ns) and a transmission in DC mode of 75 -- 80 % were achieved. With such bunch parameters, MRPs of ˜ 400,000 (FWHM) are expected for the MTOF separator. At HRIBF, it will provide pure samples of exotic nuclides around ^100Sn, of neutron deficient rare-earth nuclei and of neutron-rich nuclei. Incidental measurements of mass differences will determine Qβ values with accuracies of ˜ 1%. ^1 V. Shchepunov and V. Kozlovskiy et al., to be published

  1. New isobaric lignans from Refined Olive Oils as quality markers for Virgin Olive Oils.

    PubMed

    Cecchi, Lorenzo; Innocenti, Marzia; Melani, Fabrizio; Migliorini, Marzia; Conte, Lanfranco; Mulinacci, Nadia

    2017-03-15

    Herein we describe the influence of olive oil refining processes on the lignan profile. The detection of new isobaric lignans is suggested to reveal frauds in commercial extra-Virgin Olive Oils. We analyzed five commercial olive oils by HPLC-DAD-TOF/MS to evaluate their lignan content and detected, for the first time, some isobaric forms of natural (+)-pinoresinol and (+)-1-acetoxypinoresinol. Then we analyzed partially and fully-refined oils from Italy, Tunisia and Spain. The isobaric forms occur only during the bleaching step of the refining process and remain unaltered after the final deodorizing step. Molecular dynamic simulation helped to identify the most probable chemical structures corresponding to these new isobars with data in agreement with the chromatographic findings. The total lignan amounts in commercial olive oils was close to 2mg/L. Detection of these new lignans can be used as marker of undeclared refining procedures in commercial extra-virgin and/or Virgin Olive Oils.

  2. Rapid Analysis of Isobaric Exogenous Metabolites by Differential Mobility Spectrometry Mass Spectrometry

    SciTech Connect

    Parson, Whitney B; Schneider, Bradley B; Kertesz, Vilmos; Corr, Jay; Covey, Thomas R.; Van Berkel, Gary J

    2011-01-01

    The direct separation of isobaric glucuronide metabolites from propranolol dosed tissue extracts by differential mobility spectrometry mass spectrometry (DMS-MS) with the use of a polar gas-phase chemical modifier was demonstrated. The DMS gas-phase separation was able to resolve the isobaric metabolites with separation times on the order of ms instead of mins to hrs typically required when using pre-ionization chromatographic separation methods. Direct separation of isobaric metabolites from the complex tissue extract was validated using standards as well as implementing an HPLC separation prior to the DMS-MS analysis to pre-separate the species of interest. The ability to separate isobaric exogenous metabolites directly from a complex tissue extract is expected to facilitate the drug development process by increasing analytical throughput without the requirement for pre-ionization cleanup or separation strategies.

  3. Neutrino mean free path in neutron star matter with {delta} isobars

    SciTech Connect

    Chen Yanjun; Yuan Yefei; Liu Yuxin

    2009-05-15

    The {delta}-isobar degrees of freedom are taken into account in neutron star matter and their contributions to neutrino mean free paths are evaluated. It is found that the charged-current contributions are comparable to those from the neutral-current reactions. The contributions of {delta}-isobars may be a leading sector of neutrino opacities in neutron star matter, but the effects of the process in which the baryon transforms between nucleon and {delta} are unimportant.

  4. Δ-isobar effects on M2 strength in 208Pb

    NASA Astrophysics Data System (ADS)

    Cha, D.; Septh, J.

    1984-02-01

    The strength distribution of the 2- states in 208Pb is calculated including the Δ-isobar quenching effects. The theoretical B (M2) values up to 8 MeV are dominated by the orbital angular momentum part of the M2 operator. Therefore we find only little quenching in this energy region owing to the Δ-particle nucleon-hole admixtures. [NUCLEAR STRUCTURE 208Pb; Δ-isobar effects on M2 strength.

  5. Triptycene analogs

    NASA Technical Reports Server (NTRS)

    Hua, Duy (Inventor); Perchellet, Jean-Pierre (Inventor)

    2004-01-01

    This invention provides analogs of triptycene which are useful as anticancer drugs, as well as for other uses. The potency of these compounds is in a similar magnitude as daunomycin, a currently used anticancer drug. Each compound of the invention produces one or more desired effects (blocking nucleoside transport, inhibiting nucleic acid or protein syntheses, decreasing the proliferation and viability of cancer cells, inducing DNA fragmentation or retaining their effectiveness against multidrug-resistant tumor cells).

  6. Tagging of Isobars Using Energy Loss and Time-of-flight Measurements

    SciTech Connect

    Shapira, D.

    2001-11-02

    The technique for tagging isobars in a mixed beam by measuring energy loss by time-of-flight has been tested. With this method, isobar separation should improve by allowing more energy loss (thicker absorber), but only if one can control absorber homogeneity. Measurements of beam energy toss and energy spread obtained under such conditions were shown to be close to predicted values using both collisional and charge exchange contributions to energy straggling. The calculation of energy straggling allows us to study the efficacy of this method for isobar separation when applied to different mass ranges and beam energies. Separation in a most difficult case, an analyzed beam of A = 132 isobars at energies near 3 MeV/A has been demonstrated. The time-of-flight information can be added on line as an additional tag to the data stream for events of interest. Such event by event tagging enables one to study the effect of differences in isobaric mixture in the beam on the reaction outcome even when isobar separation is not complete.

  7. Periodicity of monoisotopic mass isomers and isobars in proteomics.

    PubMed

    Yu, Long; Xiong, Yan-Mei; Polfer, Nick C

    2011-10-15

    We report trends in the theoretically derived number of compositionally distinct peptides (i.e., peptides made up of different amino acid residues) up to a nominal mass of 1000. A total of 21 amino acid residues commonly found in proteomics studies are included in this study, 19 natural, nonisomeric amino acid residues as well as oxidated methione and acetamidated cysteine. The number of possibilities is found to increase in an exponential fashion with increasing nominal mass, and the data show a periodic oscillation that starts at mass ~200 and continues throughout to 1000. Note that similar effects are reported in the companion article on fragment ions from electron capture/transfer dissociation (ECD/ETD) (Mao et al. Anal. Chem.2011, DOI: 10.1021/ac201619t). The spacing of this oscillation is ~15 mass units at lower masses and ~14 mass units at higher nominal masses. This correlates with the most common mass differences between the amino acid building blocks. In other words, some mass differences are more common than others, thus determining the periodicity in this data. From an analytical point of view, nominal masses with a larger number of compositionally distinct peptides include a substantial number of isomers, which cannot be separated based on mass. Consequently, even ultrahigh mass accuracy (i.e., 0.5 ppm) does not lead to a substantially enhanced rate of identification. Conversely, for adjacent nominal masses with a lower number of isomers, moderately accurate mass (i.e., 10 ppm) gives a higher degree of certainty in identification. These effects are limited to the mass range between 200 and 500 Da. At higher masses, the percentage of uniquely identified peptides drops off to close to zero, independent of nominal mass, due the inherently high number of isomers. While the exact number of isobars/isomers at each nominal mass depends on the amino acid building blocks that are considered, the periodicity in the data is found to be remarkably robust; for

  8. 4C modeling of the supercritical helium loop HELIOS in isobaric configuration

    NASA Astrophysics Data System (ADS)

    Guelfi, F.; Bonifetto, R.; Hoa, C.; Savoldi, L.; Zanino, R.

    2014-11-01

    Superconducting magnets for tokamak fusion reactors are subject to highly variable loads due to the intrinsically pulsed operation of the machine. The refrigerator should, on the contrary, work under conditions as stable as possible and should be sized based on the averaged loads. In this paper, the cryogenic circuit module of the 4C (Cryogenic Circuit Conductor and Coil) code is used to analyze the isobaric configuration of the HELIOS (HElium Loop for hIgh lOads Smoothing) facility at CEA Grenoble, France. The 4C model is validated against experimental data from the isobaric HELIOS configuration: the computed evolution of temperature, pressure and mass flow rate at different circuit locations shows a good agreement with the measurements for two different pulsed heat load scenarios, with and without regulation. The advantages of the (somewhat more complicated) isobaric configuration vs. the isochoric configuration in terms of heat load smoothing are highlighted. 4C simulations are used to propose a new HELIOS layout with helium charging and discharging lines located in such a way that the HELIOS performance in the isobaric configuration is optimized. The paper confirms the importance of the isobaric configuration for a tokamak cryogenic circuit, as well as the accuracy of 4C in modeling the HELIOS operation, even in the presence of complex regulation.

  9. Covariant and self-consistent vertex corrections for pions and isobars in nuclear matter

    SciTech Connect

    Korpa, C. L.; Lutz, M. F. M.; Riek, F.

    2009-08-15

    We evaluate the pion and isobar propagators in cold nuclear matter self-consistently applying a covariant form of the isobar-hole model. Migdal's vertex correction effects are considered systematically in the absence of phenomenological soft form factors. Saturated nuclear matter is modeled by scalar and vector mean fields for the nucleon. It is shown that the short-range dressing of the {pi}N{delta} vertex has a significant effect on the pion and isobar properties. Using realistic parameters sets we predict a downward shift of about 50 MeV for the {delta} resonance at nuclear saturation density. The pionic soft modes are much less pronounced than in previous studies.

  10. Cost-effective isobaric tagging for quantitative phosphoproteomics using DiART reagents.

    PubMed

    Ramsubramaniam, Nikhil; Tao, Feng; Li, Shuwei; Marten, Mark R

    2013-12-01

    We describe the use of an isobaric tagging reagent, Deuterium isobaric Amine Reactive Tag (DiART), for quantitative phosphoproteomic experiments. Using DiART tagged custom mixtures of two phosphorylated peptides from alpha casein and their non-phosphorylated counterparts, we demonstrate the compatibility of DiART with TiO2 affinity purification of phosphorylated peptides. Comparison of theoretical vs. experimental reporter ion ratios reveals accurate quantification of phosphorylated peptides over a dynamic range of more than 15-fold. Using DiART labelling and TiO2 enrichment (DiART-TiO2) with large quantities of proteins (8 mg) from the cell lysate of model fungus Aspergillus nidulans, we quantified 744 unique phosphopeptides. Overlap of median values of TiO2 enriched phosphopeptides with theoretical values indicates accurate trends. Altogether these findings confirm the feasibility of performing quantitative phosphoproteomic experiments in a cost-effective manner using isobaric tagging reagents, DiART.

  11. The isobaric heat capacity of liquid water at low temperatures and high pressures

    NASA Astrophysics Data System (ADS)

    Troncoso, Jacobo

    2017-08-01

    Isobaric heat capacity for water shows a rather strong anomalous behavior, especially at low temperature. However, almost all experimental studies supporting this statement have been carried out at low pressure; very few experimental data were reported above 100 MPa. In order to explore the behavior of this magnitude for water up to 500 MPa, a new heat flux calorimeter was developed. With the aim of testing the experimental methodology and comparing with water results, isobaric heat capacity was also measured for methanol and hexane. Good agreement with indirect heat capacity estimations from the literature was obtained for the three liquids. Experimental results show large anomalies in water heat capacity. This is especially true as regards its temperature dependence, qualitatively different from that observed for other liquids. Heat capacity versus temperature curves show minima for most studied isobars, whose location decreases with the pressure up to around 100 MPa but increases at higher pressures.

  12. The isobaric heat capacity of liquid water at low temperatures and high pressures.

    PubMed

    Troncoso, Jacobo

    2017-08-28

    Isobaric heat capacity for water shows a rather strong anomalous behavior, especially at low temperature. However, almost all experimental studies supporting this statement have been carried out at low pressure; very few experimental data were reported above 100 MPa. In order to explore the behavior of this magnitude for water up to 500 MPa, a new heat flux calorimeter was developed. With the aim of testing the experimental methodology and comparing with water results, isobaric heat capacity was also measured for methanol and hexane. Good agreement with indirect heat capacity estimations from the literature was obtained for the three liquids. Experimental results show large anomalies in water heat capacity. This is especially true as regards its temperature dependence, qualitatively different from that observed for other liquids. Heat capacity versus temperature curves show minima for most studied isobars, whose location decreases with the pressure up to around 100 MPa but increases at higher pressures.

  13. The role of iterative isobar processes in nuclear matter and the effective nucleon-nucleon interaction

    NASA Astrophysics Data System (ADS)

    Dey, J.; Samanta, B. C.; Dey, M.

    1980-09-01

    A calculation is performed using lowest order Brueckner theory in momentum space, with explicit isobar configurations included through the coupled channel mathod. The effective interaction for the1 S 0-5 D 0 channel is extracted from this calculation. Two different transition potentials are used — one due to Green and Niskanen (1976), the other, due to Green and co-workers (1978). The nucleon-nucleon (NN) interaction used is the Reid soft core potential, compensated for the inclusion of the explicit isobar channel. The effective interaction shows marked momentum dependence in the intermediate range. The loss of attraction depends on the transition potential one chooses. The correlation function involving the nucleon-isobar intermediate state is anti-correlated to the NN part.

  14. Isobaric expansion coefficient and isothermal compressibility for a finite-size ideal Fermi gas system

    NASA Astrophysics Data System (ADS)

    Su, Guozhen; Chen, Liwei; Chen, Jincan

    2014-06-01

    Due to quantum size effects (QSEs), the isobaric thermal expansion coefficient and isothermal compressibility well defined for macroscopic systems are invalid for finite-size systems. The two parameters are redefined and calculated for a finite-size ideal Fermi gas confined in a rectangular container. It is found that the isobaric thermal expansion coefficient and isothermal compressibility are generally anisotropic, i.e., they are generally different in different directions. Moreover, it is found the thermal expansion coefficient may be negative in some directions under the condition that the pressures in all directions are kept constant.

  15. A comparison of freezing-damage during isochoric and isobaric freezing of the potato

    PubMed Central

    Serban, Alexandru; Rubinsky, Boris

    2017-01-01

    Background Freezing is commonly used for food preservation. It is usually done under constant atmospheric pressure (isobaric). While extending the life of the produce, isobaric freezing has detrimental effects. It causes loss of food weight and changes in food quality. Using thermodynamic analysis, we have developed a theoretical model of the process of freezing in a constant volume system (isochoric). The mathematical model suggests that the detrimental effects associated with isobaric freezing may be reduced in an isochoric freezing system. To explore this hypothesis, we performed a preliminary study on the isochoric freezing of a produce with which our group has experience, the potato. Method Experiments were performed in an isochoric freezing device we designed. The device is robust and has no moving parts. For comparison, we used a geometrically identical isobaric freezing device. Following freezing and thawing, the samples were weighed, examined with colorimetry, and examined with microscopy. Results It was found that potatoes frozen to −5 °C in an isochoric system experienced no weight loss and limited enzymatic browning. In contrast the −5 °C isobaric frozen potato experienced substantial weight loss and substantial enzymatic browning. Microscopic analysis shows that the structural integrity of the potato is maintained after freezing in the isochoric system and impaired after freezing in the isobaric system. Discussion Tissue damage during isobaric freezing is caused by the increase in extracellular osmolality and the mechanical damage by ice crystals. Our thermodynamic analysis predicts that during isochoric freezing the intracellular osmolality remains comparable to the extracellular osmolality and that isochoric systems can be designed to eliminate the mechanical damage by ice. The results of this preliminary study seem to confirm the theoretical predictions. Conclusion This is a preliminary exploratory study on isochoric freezing of food. We have

  16. Gas-phase purification enables accurate, large-scale, multiplexed proteome quantification with isobaric tagging

    PubMed Central

    Wenger, Craig D; Lee, M Violet; Hebert, Alexander S; McAlister, Graeme C; Phanstiel, Douglas H; Westphall, Michael S; Coon, Joshua J

    2011-01-01

    We describe a mass spectrometry method, QuantMode, which improves the accuracy of isobaric tag–based quantification by alleviating the pervasive problem of precursor interference—co-isolation of impurities—through gas-phase purification. QuantMode analysis of a yeast sample ‘contaminated’ with interfering human peptides showed substantially improved quantitative accuracy compared to a standard scan, with a small loss of spectral identifications. This technique will allow large-scale, multiplexed quantitative proteomics analyses using isobaric tagging. PMID:21963608

  17. Quantitation of isobaric phosphatidylcholine species in human plasma using a hybrid quadrupole linear ion trap mass spectrometer

    USDA-ARS?s Scientific Manuscript database

    Phosphatidylcholine (PC) species in human plasma are used as biomarkers of disease. PC biomarkers are often limited by the inability to separate isobaric PC. In this work, we developed a targeted shotgun approach for analysis of isobaric and isomeric PC. This approach is comprised of two mass spectr...

  18. Strategies for differentiation of isobaric flavonoids using liquid chromatography coupled to electrospray ionization mass spectrometry.

    PubMed

    Fridén, Mikael E; Sjöberg, Per J R

    2014-07-01

    Flavonoids are a class of secondary plant metabolites existing in great variety in nature. Due to this variety, identification can be difficult, especially as overlapping compounds in both chromatographic separations and mass spectrometric detection are common. Methods for distinguishing isobaric flavonoids using MS(2) and MS(3) have been developed. Chromatographic separation of various plant extracts was done with RP-HPLC and detected with positive ESI-MS operated in information-dependent acquisition (IDA) mode. Two methods for the determination of flavonoid identity and substitution pattern, both featuring IDA criteria, were used together with the HPLC equipment. A third method where the collision energy was ramped utilized direct infusion. With the developed strategies, it is possible to differentiate between many isobaric flavonoids. Various classes of flavonoids were found in all of the plant extracts, in the red onion extract 45 components were detected and for 29 of them the aglycone was characterized, while the substituents were tentatively identified for 31 of them. For the strawberry extract, those numbers were 66, 30 and 60, and for the cherry extract 99, 56 and 71. The great variety of flavonoids, several of them isobaric, found in each of the extracts highlights the need for reliable methods for flavonoid characterization. Methods capable of differentiating between most of the isobars analyzed have been developed.

  19. Tandem mass spectrometric analysis of a mixture of isobars using the survival yield technique.

    PubMed

    Memboeuf, Antony; Jullien, Laure; Lartia, Rémy; Brasme, Bernard; Gimbert, Yves

    2011-10-01

    Collision induced dissociation tandem mass spectrometry experiments were performed to unequivocally separate compounds from an isobaric mixture of two products. The Survival Yield curve was obtained and is shown to consist in a linear combination of the curves corresponding to the two components separately. For such a mixture, a plateau appears on the diagram in lieu of the continuous decrease expected allowing for the structural study of the two components separately. The width of the plateau critically relates to the fragmentation parameters of the two molecular ions, which need to be sufficiently different structurally for the plateau to be observed. However, at constant fragmentation parameters, we have observed the width significantly increases at large m/z. This makes the separation more and more efficient as isobars have larger m/z and the technique complementary to those applicable at low m/z only. We have observed that the vertical position of the plateau relates linearly to the relative concentration of the two compounds that may be useful for quantification. Repeatability was estimated at 2% on a quadrupole ion trap. An advantage of using survival yield curves only, is that a priori knowledge of the respective fragmentation patterns of the two isobars becomes unnecessary. Consequently, similar performances are obtained if fragments are isobaric, which is also demonstrated in our study. The critical case of reverse peptides, at low m/z and similar fragmentation parameters, is also presented as a limitation of the method.

  20. Formation of isobaric discontinuities in large-scale flute drift motions

    SciTech Connect

    Dreizin, Y.A.; Sokolov, E.P.

    1982-05-01

    The flute drift motion in MHD-stable plasma configurations with closed lines of force is analyzed qualitatively. The onset of this motion can lead to isobaric discontinuities in experimentally observable quantitites: the electric potential and the electron and ion densities and temperatures.

  1. High-Resolution Enabled 12-Plex DiLeu Isobaric Tags for Quantitative Proteomics

    PubMed Central

    2015-01-01

    Multiplex isobaric tags (e.g., tandem mass tags (TMT) and isobaric tags for relative and absolute quantification (iTRAQ)) are a valuable tool for high-throughput mass spectrometry based quantitative proteomics. We have developed our own multiplex isobaric tags, DiLeu, that feature quantitative performance on par with commercial offerings but can be readily synthesized in-house as a cost-effective alternative. In this work, we achieve a 3-fold increase in the multiplexing capacity of the DiLeu reagent without increasing structural complexity by exploiting mass defects that arise from selective incorporation of 13C, 15N, and 2H stable isotopes in the reporter group. The inclusion of eight new reporter isotopologues that differ in mass from the existing four reporters by intervals of 6 mDa yields a 12-plex isobaric set that preserves the synthetic simplicity and quantitative performance of the original implementation. We show that the new reporter variants can be baseline-resolved in high-resolution higher-energy C-trap dissociation (HCD) spectra, and we demonstrate accurate 12-plex quantitation of a DiLeu-labeled Saccharomyces cerevisiae lysate digest via high-resolution nano liquid chromatography–tandem mass spectrometry (nanoLC–MS2) analysis on an Orbitrap Elite mass spectrometer. PMID:25405479

  2. Masses of proton-rich T/sub z/<0 nuclei via the isobaric mass equation

    SciTech Connect

    Pape, A.; Antony, M.S.

    1988-07-01

    Masses of T/sub z/<0 nuclei through the element Sm, corresponding to Aless than or equal to117, have been calculated with the isobaric multiplet mass equation using parameterizations of its constant b and T/sub z/>0 reference masses of Wapstra, Audi, and Hoekstra. copyright 1988 Academic Press, Inc.

  3. Residue Coulomb Interaction Among Isobars and Its Influence in Symmetry Energy of Neutron-Rich Fragment

    NASA Astrophysics Data System (ADS)

    Ma, Chun-Wang; Wang, Shan-Shan; Zhang, Yan-Li; Zhao, Yi-Long; Wei, Hui-Ling

    2015-09-01

    The residue Coulomb interaction (RCI), which affects the result of symmetry-energy coefficient of neutron-rich nucleus in isobaric yield ratio (IYR) method, is difficult to be determined. Four RCI approximations are investigated: (i) The M1-RCI adopting the ac/T (the ratio of Coulomb energy coefficient to temperature) determined from the IYR of mirror-nucleus fragments; (ii) The M2-RCI by fitting the difference between IYRs; (iii) The M3-RCI adopting the standard Coulomb energy at a temperature T = 2 MeV; and (iv) Neglecting the RCI among isobars. The M1-, M2- and M3-RCI are no larger than 0.4. In particular, the M2-RCI is very close to zero. The effects of RCI in asym/T of fragment are also studied. The M1- and M4-asym/T are found to be the lower and upper limitations of asym/T, respectively. The M2-asym/T overlaps the M4-asym/T, which indicates that the M2-RCI is negligible in the IYR method, and the RCI among the three isobars can be neglected. The relative consistent low values of M3-asym/T (7.5 ± 2.5) are found in very neutron-rich isobars. Supported by the Program for Science & Technology Innovation Talents in Universities of Henan Province (13HASTIT046), and Young Teacher Project in Henan Normal University (HNU), China

  4. MilQuant: a free, generic software tool for isobaric tagging-based quantitation.

    PubMed

    Zou, Xiao; Zhao, Minzhi; Shen, Hongyan; Zhao, Xuyang; Tong, Yuanpeng; Wang, Qingsong; Wei, Shicheng; Ji, Jianguo

    2012-09-18

    Isobaric tagging techniques such as iTRAQ and TMT are widely used in quantitative proteomics and especially useful for samples that demand in vitro labeling. Due to diversity in choices of MS acquisition approaches, identification algorithms, and relative abundance deduction strategies, researchers are faced with a plethora of possibilities when it comes to data analysis. However, the lack of generic and flexible software tool often makes it cumbersome for researchers to perform the analysis entirely as desired. In this paper, we present MilQuant, mzXML-based isobaric labeling quantitator, a pipeline of freely available programs that supports native acquisition files produced by all mass spectrometer types and collection approaches currently used in isobaric tagging based MS data collection. Moreover, aside from effective normalization and abundance ratio deduction algorithms, MilQuant exports various intermediate results along each step of the pipeline, making it easy for researchers to customize the analysis. The functionality of MilQuant was demonstrated by four distinct datasets from different laboratories. The compatibility and extendibility of MilQuant makes it a generic and flexible tool that can serve as a full solution to data analysis of isobaric tagging-based quantitation.

  5. Quantification by isobaric labeling (QUIBL) for the comparative glycomic study of O-linked glycans

    NASA Astrophysics Data System (ADS)

    Botelho, Julianne Cook; Atwood, James A., III; Cheng, Lei; Alvarez-Manilla, Gerardo; York, William S.; Orlando, Ron

    2008-12-01

    Quantification by isobaric labeling (QUIBL) has recently been described as a tool for the relative quantification of N-linked glycans in glycomic studies. In this paper we expand the application of QUIBL to the relative quantification of O-linked glycans. Fetuin, which contains two O-linked glycans, NeuAc-Hex-HexNAc and NeuAc2-Hex-HexNAc, was used to validate this studyE The glycans were released by [beta]-elimination and permethylated with the isobaric labeling reagents, 13CH3I and 12CH2DI. The exact mass difference between the isobaric labels is minimal (0.00292 Da), but since glycans contain multiple permethylation sites, the mass difference can be resolved with a high resolution mass spectrometer, such as an FTMS. Quantitative data were obtained by comparing the signal intensities from various mixtures of isobarically labeled O-linked glycans of fetuin. Five different ratios of 13CH3 to 12CH2D ranging from 10:1 to 1:10 were analyzed for linearity and reproducibility of the QUIBL method on the standard glycan. QUIBL was also evaluated using porcine mucin, a sample with a larger variety of more complex O-linked glycans. These results indicate that QUIBL allows for the relative quantification of O-linked glycans over a linear dynamic range of at least two orders of magnitude, validating QUIBL as an applicable quantitative glycomics approach for both N-linked and O-linked glycans.

  6. Conception of PIPERADE: A high-capacity Penning-trap mass separator for high isobaric contamination at DESIR

    NASA Astrophysics Data System (ADS)

    Minaya Ramirez, E.; Alfaurt, P.; Aouadi, M.; Ascher, P.; Blank, B.; Blaum, K.; Cam, J.-F.; Chauveau, P.; Daudin, L.; Delahaye, P.; Delalee, F.; Dupré, P.; El Abbeir, S.; Gerbaux, M.; Grévy, S.; Guérin, H.; Lunney, D.; Metz, F.; Naimi, S.; Perrot, L.; de Roubin, A.; Serani, L.; Thomas, B.; Thomas, J.-C.

    2016-06-01

    The DESIR (decay, excitation and storage of radioactive ions) facility at GANIL-SPIRAL2 will receive a large variety of exotic nuclei at low energy (up to 60 keV) with high intensities. However, the production methods of radioactive beams are non selective, limiting the purity of the beams of interest. Moreover, the high precision needed for nuclear structure and astrophysics studies using beta decay spectroscopy, laser spectroscopy and trap-based experiments at DESIR requires highly pure samples of exotic nuclei. The aim of the double-Pennig-trap mass separator PIPERADE is to deliver large and very pure samples of exotic nuclei to the different experiments in DESIR. New excitation schemes and a large inner diameter of the first trap will mitigate space charge effects to attempt trapping of up to 105 ions per pulse. The purification cycle will be performed in a few milliseconds so that short-lived nuclei can be purified. To extract the nuclides of interest from the large amount of isobaric contaminants, a resolving power of 105 is mandatory. Afterwards the ions of interest will be accumulated in the second trap until they constitute a sufficiently pure sample for the measurements. The status of the project is presented.

  7. When Gesture Becomes Analogy.

    PubMed

    Cooperrider, Kensy; Goldin-Meadow, Susan

    2017-07-01

    Analogy researchers do not often examine gesture, and gesture researchers do not often borrow ideas from the study of analogy. One borrowable idea from the world of analogy is the importance of distinguishing between attributes and relations. Gentner (, ) observed that some metaphors highlight attributes and others highlight relations, and called the latter analogies. Mirroring this logic, we observe that some metaphoric gestures represent attributes and others represent relations, and propose to call the latter analogical gestures. We provide examples of such analogical gestures and show how they relate to the categories of iconic and metaphoric gestures described previously. Analogical gestures represent different types of relations and different degrees of relational complexity, and sometimes cohere into larger analogical models. Treating analogical gestures as a distinct phenomenon prompts new questions and predictions, and illustrates one way that the study of gesture and the study of analogy can be mutually informative. Copyright © 2017 Cognitive Science Society, Inc.

  8. Analog current mode analog/digital converter

    NASA Technical Reports Server (NTRS)

    Hadidi, Khayrollah (Inventor)

    1996-01-01

    An improved subranging or comparator circuit is provided for an analog-to-digital converter. As a subranging circuit, the circuit produces a residual signal representing the difference between an analog input signal and an analog of a digital representation. This is achieved by subdividing the digital representation into two or more parts and subtracting from the analog input signal analogs of each of the individual digital portions. In another aspect of the present invention, the subranging circuit comprises two sets of differential input pairs in which the transconductance of one differential input pair is scaled relative to the transconductance of the other differential input pair. As a consequence, the same resistor string may be used for two different digital-to-analog converters of the subranging circuit.

  9. Isobar model analysis of {pi}{sup 0{eta}} photoproduction on protons

    SciTech Connect

    Fix, A.; Lee, A.; Kashevarov, V. L.; Ostrick, M.

    2010-09-15

    Photoproduction of {pi}{sup 0{eta}} on protons in the energy range from threshold to 1.4 GeV is discussed. The data for representative angular distributions recently obtained at MAMI C are analyzed using an isobar model. The isobars considered are {Delta}(1232) and S{sub 11}(1535) for {pi}{sup 0}p and {eta}p states, respectively. In accordance with the results of earlier works, the main features of the reaction are explained through the dominance of the D{sub 33} wave with a relatively small admixture of positive parity resonances. Comparison with recent experimental results for the photon beam asymmetry is carried out.

  10. Isobars of an ideal Bose gas within the grand canonical ensemble

    SciTech Connect

    Jeon, Imtak; Park, Jeong-Hyuck; Kim, Sang-Woo

    2011-08-15

    We investigate the isobar of an ideal Bose gas confined in a cubic box within the grand canonical ensemble for a large yet finite number of particles, N. After solving the equation of the spinodal curve, we derive precise formulas for the supercooling and the superheating temperatures that reveal an N{sup -1/3} or N{sup -1/4} power correction to the known Bose-Einstein condensation temperature in the thermodynamic limit. Numerical computations confirm the accuracy of our analytical approximation, and further show that the isobar zigzags on the temperature-volume plane if N{>=}14 393. In particular, for the Avogadro's number of particles, the volume expands discretely about 10{sup 5} times. Our results quantitatively agree with a previous study on the canonical ensemble within 0.1% error.

  11. Isobars of an ideal Bose gas within the grand canonical ensemble

    NASA Astrophysics Data System (ADS)

    Jeon, Imtak; Kim, Sang-Woo; Park, Jeong-Hyuck

    2011-08-01

    We investigate the isobar of an ideal Bose gas confined in a cubic box within the grand canonical ensemble for a large yet finite number of particles, N. After solving the equation of the spinodal curve, we derive precise formulas for the supercooling and the superheating temperatures that reveal an N-1/3 or N-1/4 power correction to the known Bose-Einstein condensation temperature in the thermodynamic limit. Numerical computations confirm the accuracy of our analytical approximation, and further show that the isobar zigzags on the temperature-volume plane if N≥14393. In particular, for the Avogadro’s number of particles, the volume expands discretely about 105 times. Our results quantitatively agree with a previous study on the canonical ensemble within 0.1% error.

  12. Quantitation of protein post-translational modifications using isobaric tandem mass tags.

    PubMed

    Liang, Hui-Chung; Lahert, Emma; Pike, Ian; Ward, Malcolm

    2015-01-01

    Post-translational modifications (PTMs) of proteins are known to modulate many cellular processes and their qualitative and quantitative evaluation is fundamental for understanding the mechanisms of biological events. Over the past decade, improvements in sample preparation techniques and enrichment strategies, the development of quantitative labeling strategies, the launch of a new generation of mass spectrometers and the creation of bioinformatics tools for the interrogation of ever larger datasets has established MS-based quantitative proteomics as a powerful workflow for global proteomics, PTM analysis and the elucidation of key biological mechanisms. With the advantage of their multiplexing capacity and the flexibility of an ever-growing family of different peptide-reactive groups, isobaric tandem mass tags facilitate quantitative proteomics and PTM experiments and enable higher sample throughput. In this review, we focus on the technical concept and utility of the isobaric tandem mass tag labeling approach to PTM analysis, including phosphorylation, glycosylation and S-nitrosylation.

  13. Revalidation of the isobaric multiplet mass equation for the A=20 quintet

    DOE PAGES

    Glassman, B. E.; Pérez-Loureiro, D.; Wrede, C.; ...

    2015-10-29

    An unexpected breakdown of the isobaric multiplet mass equation in the A = 20, T = 2 quintet was recently reported, presenting a challenge to modern theories of nuclear structure. In the present work, the excitation energy of the lowest T = 2 state in Na-20 has been measured to be 6498.4 +/- 0.2stat ± 0.4syst keV by using the superallowed 0+ → 0+ beta decay of Mg-20 to access it and an array of high-purity germanium detectors to detect its gamma-ray deexcitation. This value differs by 27 keV (1.9 standard deviations) from the recommended value of 6525 ± 14more » keV and is a factor of 28 more precise. The isobaric multiplet mass equation is shown to be revalidated when the new value is adopted.« less

  14. Isobaric Heat Capacity, Isothermal Compressibility and Fluctuational Properties of 1-Bromoalkanes

    NASA Astrophysics Data System (ADS)

    Korotkovskii, V. I.; Ryshkova, O. S.; Neruchev, Yu. A.; Goncharov, A. L.; Postnikov, E. B.

    2016-06-01

    We present results of the experimental measurements of the isobaric heat capacity for 1-bromohexane, 1-bromoheptane, 1-bromooctane, 1-bromononane, 1-bromodecane, 1-bromoundecane, 1-bromododecane and 1-bromotetradecane at normal pressure and the speed of sound and the density for 1-bromotetradecane within the temperature range 298.15-423.15 K. These data on the isobaric heat capacity and the literature-based reference data for the density and the speed of sound were used to calculate the isothermal compressibility and the inverse reduced fluctuations. Based on the comparison of the results for pure n-alkanes and α ,ω -dibromoalkanes, we discuss the influence of bromine atom on the volume fluctuations.

  15. [Clinical research of hyperbaric, isobaric, and hypobaric solutions of bupivacaine in continuous spinal anesthesia].

    PubMed

    Yang, Hong-wei; Bai, Nian-yue; Guo, Qu-lian

    2005-02-01

    To compare the anesthesia properities of hyperbaric bupivacaine with those of isobaric and hypobaric solutions when administered in the supine position undergoing hip surgery or lower limb surgery using continuous spinal anesthesia. Sixty patients( ASA I approximately III ) scheduled for hip or lower limb surgery were randomly divided into 3 groups with 20 patients in each group: Group A: 0. 375% hyperbaric bupivacaine solutions; Group B :0.375% isobaric bupivacaine solutions; and Group C: 0. 375% hypobaric bupivacaine solutions. The following variables were measured every 2 minutes during the first 30 minutes after the intrathecal injection : the onset time of sensation block, the highest plane of analgesia, the time to reach complete motor blockade, and the plane of analgesia and the extent of lower extremities' movement (modified bromage score, BMS) at different time after the administration. Meanwhile the changes of hemodynamics were recorded. There was no statistical difference among the basic conditions ( P > 0.05). The onset time of sensation block, and the time to reach complete motor blockade, and the time receiving the highest sharp pain sensory block in Group A were significantly shorter than those in Group B and Group C ( P < 0.01 ). The plane of analgesia obtained in the hyperbaric group was significantly higher than in both the isobaric and the hypobaric groups ( P < 0.01). The mean arterial pressure(MAP) , HR in the hyperbaric group decreased significantly after the intrathecal injection( P < 0.05 ). The 0.375% Isobaric bupivacaine used during contiuous spinal anesthesia in the supine position produces a suitable and a more "controllable" anesthesia, but a minimum dosage of 10 approximately 12.5 mg is required to obtain adequate anesthesic conditions with moderate hemodynamic changes and satisfying analgesia effects. Under similar conditions, 0. 375% hyperbaric bupivacaine produces major hemodynamic consequences with high cephalad spread and 0. 375

  16. Oxygen chemisorption on V/sub 2/O/sub 5/: isotherms and isobars of adsorption

    SciTech Connect

    Rey, L.; Gambaro, L.A.; Thomas, H.J.

    1984-06-01

    Experimental results of oxygen adsorption on V/sub 2/O/sub 5/ (isotherms and isobars) are reported. In its normal state V/sub 2/O/sub 5/ is a nonstoichiometric oxide that shows oxygen vacancies with the subsequent formation of V/sup 4 +/ ions. A model is developed for the interaction between oxygen (gaseous, adsorbed, and bulk) and the solid phase (V/sub 2/O/sub 5/). 12 references, 4 figures, 1 table.

  17. Isobaric vapor-liquid equilibria of methanol + 1-octanol and ethanol + 1-octanol mixtures

    SciTech Connect

    Arce, A.; Blanco, A.; Soto, A.; Tojo, J.

    1995-07-01

    Isobaric vapor-liquid equilibrium data for methanol + 1-octanol and ethanol + 1-octanol have been measured at 101.325 kPa. The results were checked for thermodynamic consistency using Fredenslund et al.`s test, correlated using Wilson, NRTL, and UNIQUAC equations for the liquid phase activity coefficients, and compared with the predictions of the ASOG, UNIFAC, and modified UNIFAC group contribution methods.

  18. A regression model for calculating the boiling point isobars of tetrachloromethane-based binary solutions

    NASA Astrophysics Data System (ADS)

    Preobrazhenskii, M. P.; Rudakov, O. B.

    2016-01-01

    A regression model for calculating the boiling point isobars of tetrachloromethane-organic solvent binary homogeneous systems is proposed. The parameters of the model proposed were calculated for a series of solutions. The correlation between the nonadditivity parameter of the regression model and the hydrophobicity criterion of the organic solvent is established. The parameter value of the proposed model is shown to allow prediction of the potential formation of azeotropic mixtures of solvents with tetrachloromethane.

  19. Resonance ionization mass spectrometric study of the promethium/samarium isobaric pair

    SciTech Connect

    Shaw, R.W.; Young, J.P.; Smith, D.H.

    1988-01-01

    Samarium daughters are problematic in isotope ratio measurements of promethium because they are isobaric. Resonance ionization mass spectrometry was utilized to circumvent this problem. An ionization selectivity factor of at least 1000:1 has been measured for promethium over samarium at 584.6 nm. Resonance ionization spectra have been recorded for both elements over the 528-560 and 580-614 nm wavelength ranges.

  20. Partially isobaric peptide termini labeling assisted proteome quantitation based on MS and MS/MS signals.

    PubMed

    Zhang, Shen; Wu, Qi; Shan, Yichu; Zhou, Yuan; Zhang, Lihua; Zhang, Yukui

    2015-01-30

    Isotopic labeling and isobaric labeling are two kinds of the typical quantification method that have been widely used in proteomics analysis. Herein, a novel quantitative strategy, partially isobaric peptide termini labeling (PITL), was developed to overcome the drawbacks of each above-mentioned labeling strategy, by simultaneously collecting the quantitative information from both MS and MS/MS spectrum. PITL is based on the site-selective N-terminus dimethylation labeling of peptide α-N-termini and the free ε-amino group of lysines, resulting in the partially isobaric labeling of peptides. The relative quantification can then be achieved by comparing the intensities of precursor ions in MS spectra and a, b and y ions in MS/MS spectra. The quantitative analysis of differently labeled yeast digests pooled with various ratios indicated the good quantitative accuracy, reproducibility, coverage and wide dynamic range of PITL strategy. Furthermore, PITL was applied to the quantitative proteome analysis of two mouse hepatocarcinoma ascites syngeneic cell lines with low and high lymph node metastasis rates (Hca-F and Hca-P). Given its low cost, simple operation and good accuracy, PITL might have great potential in the quantitative proteome analysis of biological samples. The partially isobaric peptide termini labeling (PITL) method enabled to simultaneously obtain the quantitative information from MS and MS/MS spectrum, which combined the advantages of these two strategies. Relative quantification could be achieved by comparing the intensities of parent ions in MS spectra and a, b, y ions in the MS/MS spectra. The quantitative analysis for differently labeled yeast digests mixed at various ratios indicated the good accuracy, reproducibility, quantitative coverage and wide dynamic range of the PITL strategy. Finally, we found 84 differentially expressed proteins in mouse hepatocarcinoma ascites syngeneic cell lines with low and high lymph node metastasis rates with PITL

  1. [Nursing Care of Lumbar Spine Fusion Surgery Using a Semi-Rigid Device (ISOBAR)].

    PubMed

    Wu, Meng-Shan; Su, Shu-Fen

    2016-04-01

    Aging frequently induces degenerative changes in the spine. Patients who suffer from lumbar degenerative disease tend to have lower back pain, neurological claudication, and neuropathy. Furthermore, incontinence may be an increasing issue as symptoms become severe. Lumbar spine fusion surgery is necessary if clinical symptoms continue to worsen or if the patient fails to respond to medication, physical therapy, or alternative treatments. However, this surgical procedure frequently induces adjacent segment disease (ASD), which is evidenced by the appearance of pathological changes in the upper and lower sections of the spinal surgical sites. In 1997, ISOBAR TTL dynamic rod stabilization was developed for application in spinal fusion surgery to prevent ASD-related complications. The device has proven effective in reducing pain in the lower back and legs, decreasing functional disability, improving quality of life, and retarding disc degeneration. However, the effectiveness of this intervention in decreasing the incidence of ASD requires further research investigation, and relevant literature and research in Taiwan is still lacking. This article discusses lumbar degenerative disease, its indications, the contraindications of lumbar spine fusion surgery using ISOBAR, and related postoperative nursing care. We hope this article provides proper and new knowledge to clinical nurses for the care of patients undergoing lumbar spine fusion surgery with ISOBAR.

  2. Increasing the multiplexing capacity of TMT using reporter ion isotopologues with isobaric masses

    PubMed Central

    McAlister, Graeme C.; Huttlin, Edward L.; Haas, Wilhelm; Ting, Lily; Jedrychowski, Mark P.; Rogers, John C.; Kuhn, Karsten; Pike, Ian; Grothe, Robert A.; Blethrow, Justin D.; Gygi, Steven P.

    2013-01-01

    Quantitative mass spectrometry methods offer near-comprehensive proteome coverage; however, these methods still suffer with regards to sample throughput. Multiplex quantitation via isobaric chemical tags (e.g., TMT and iTRAQ) provides an avenue for mass spectrometry based proteome quantitation experiments to move away from simple binary comparisons and towards greater parallelization. Herein, we demonstrate a straightforward method for immediately expanding the throughput of the TMT isobaric reagents from 6-plex to 8-plex. This method is based upon our ability to resolve the isotopic shift that results from substituting a 15N for a 13C. In an accommodation to the preferred fragmentation pathways of ETD, the TMT-127 and -129 reagents were recently modified such that a 13C was exchanged for a 15N. As a result of this substitution, the new TMT reporter ions are 6.32 mDa lighter. Even though the mass difference between these reporter ion isotopologues is incredibly small, modern high-resolution and mass accuracy analyzers can resolve these ions. Based on our ability to resolve and accurately measure the relative intensity of these isobaric reporter ions, we demonstrate that we are able to quantify across 8 samples simultaneously by combining the 13C and 15N containing reporter ions. Considering the structure of the TMT reporter ion, we believe this work serves as a blueprint for expanding the multiplexing capacity of the TMT reagents to at least 10-plex and possibly up to 18-plex. PMID:22880955

  3. Scaling phenomena of isobaric yields in projectile fragmentation, spallation, and fission reactions

    NASA Astrophysics Data System (ADS)

    Ma, Chun-Wang; Huang, Ling; Song, Yi-Dan

    2017-02-01

    Background: The isobaric ratio difference scaling phenomenon, which has been found for the fragments produced in projectile fragmentation reactions, is related to the nuclear density change in reaction systems. Purpose: To verify whether the isobaric ratio difference scaling exists in the fragments produced in the spallation and fission reactions. Methods: The isobaric ratio difference scaling, denoted by SΔ lnR21 , is in theory deduced within the framework of the canonical ensemble theory at the grand-canonical limitation. The fragments measured in a series of projectile fragmentation, spallation, and fission reactions have been analyzed. Results: A good SΔ lnR21 scaling phenomenon is shown for the fragments produced both in the projectile fragmentation reactions and in the spallation reactions, whereas the SΔ lnR21 scaling phenomenon for the fragments in the fission reaction is less obvious. Conclusions: The SΔ lnR21 scaling is used to probe the properties of the equilibrium system at the time of fragment formation. The good scaling of SΔ lnR21 suggests that the equilibrium state can be achieved in the projectile fragmentation and spallation reactions. Whereas in the fission reaction, the result of SΔ lnR21 indicates that the equilibrium of the system is hard to achieve.

  4. Learning by Analogy: Discriminating between Potential Analogs

    ERIC Educational Resources Information Center

    Richland, Lindsey E.; McDonough, Ian M.

    2010-01-01

    The ability to successfully discriminate between multiple potentially relevant source analogs when solving new problems is crucial to proficiency in a mathematics domain. Experimental findings in two different mathematical contexts demonstrate that providing cues to support comparative reasoning during an initial instructional analogy, relative to…

  5. Dialysate pressure isobars in a hollow-fiber dialyzer determined from magnetic resonance imaging and numerical simulation of dialysate flow.

    PubMed

    Osuga, T; Obata, T; Ikehira, H; Tanada, S; Sasaki, Y; Naito, H

    1998-10-01

    A procedure to determine dialysate pressure isobars by comparing the results of magnetic resonance imaging (MRI) and numerical simulation of the dialysate flow was established. The assumption used in the filtration analyses, that the dialysate pressure varies only in the central-axial direction, is supported by the finding that the determined isobars have no steep radial gradient. MRI of the contrast solution permeating the hollow fibers verifies the uniformity of the hollow fiber density in the dialyzer.

  6. Isobaric Molecular Dynamics Version of the Generalized Replica Exchange Method (gREM): Liquid-Vapor Equilibrium.

    PubMed

    Małolepsza, Edyta; Secor, Maxim; Keyes, Tom

    2015-10-22

    A prescription for sampling isobaric generalized ensembles with molecular dynamics is presented and applied to the generalized replica exchange method (gREM), which was designed to simulate first-order phase transitions. The properties of the isobaric gREM ensemble are discussed, and a study is presented for the liquid-vapor equilibrium of the guest molecules given for gas hydrate formation with the mW water model. Phase diagrams, critical parameters, and a law of corresponding states are obtained.

  7. Use of hyperbaric versus isobaric bupivacaine for spinal anaesthesia for caesarean section.

    PubMed

    Sia, Alex T; Tan, Kelvin H; Sng, Ban Leong; Lim, Yvonne; Chan, Edwin S Y; Siddiqui, Fahad Javaid

    2013-05-31

    Bupivacaine is an amide local anaesthetic used in hyperbaric and isobaric forms. These are administered intrathecally into the spine to provide regional anaesthesia for caesarean section. Several trials have compared hyperbaric and isobaric bupivacaine but none have conclusively shown benefit of either. This systematic review aimed to summarize the effectiveness and safety of hyperbaric versus isobaric bupivacaine in providing anaesthesia for caesarean section. We considered the adequacy of anaesthesia for completion of caesarean section and the need for interventions to treat complications. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 4), MEDLINE (January 1966 to May 2011) and EMBASE (January 1980 to May 2011). We handsearched journals. We imposed no language restriction. We reran our search in the above databases from January 2011 to January 2013; the studies are awaiting assessment and will be dealt with when we update the review. We included all randomized controlled trials involving parturients undergoing spinal anaesthesia for elective caesarean section that compared the use of hyperbaric with isobaric bupivacaine. Two authors independently extracted the data. The data that were extracted included the number of events and the sample sizes in both the intervention and control groups. For continuous outcomes, we extracted mean and standard deviation.We reported odds ratios and risk ratios (RR) for binary outcomes and mean differences (MD) for continuous outcomes. We included six studies with a total of 394 patients in this review. Anaesthesia performed with hyperbaric bupivacaine appeared to be less likely to need conversion to general anaesthesia (two studies, 158 patients included in meta-analysis; RR 0.17, 95% confidence interval (CI) 0.03 to 0.94). There was no difference in the need for supplemental analgesics. The time till sensory block to the T4 level was also shorter with hyperbaric

  8. Measurement of pion double charge exchange on carbon-13, carbon-14, magnesium-26, and iron-56

    SciTech Connect

    Seidl, P.A.

    1985-02-01

    Cross sections for the /sup 13,14/C,/sup 26/Mg,/sup 56/Fe(..pi../sup +/,..pi../sup -/)/sup 13,14/O,/sup 26/Si,/sup 56/Ni reactions were measured with the Energetic Pion Channel and Spectrometer at the Clinton P. Anderson Meson Physics Facility for 120 less than or equal to T/sub ..pi../ less than or equal to 292 MeV and 0 less than or equal to theta less than or equal to 50. The double isobaric analog states (DIAS) are of primary interest. In addition, cross sections for transitions to /sup 14/O(0/sup +/, 5.92 MeV), /sup 14/O(2/sup +/, 7.77 MeV), /sup 56/Ni(gs), /sup 13/O(gs), and /sup 13/O(4.21 MeV) are presented. The /sup 13/O(4.21 MeV) state is postulated to have J/sup ..pi../ = 1/2/sup -/. The data are compared to previously measured double-charge-exchange cross sections on other nuclei, and the systematics of double charge exchange on T greater than or equal to 1 target nuclei leading to the DIAS are studied. Near the ..delta../sub 33/ resonance, cross sections for the DIAS transitions are in disagreement with calculations in which the reaction is treated as sequential charge exchange through the free pion-nucleon amplitude, while for T/sub ..pi../ > 200 MeV the anomalous features of the 164 MeV data are not apparent. This is evidence for significant higher order contributions to the double-charge-exchange amplitude near the reasonable energy. Two theoretical approaches that include two nucleon processes are applied to the DIAS data. 64 references.

  9. Radioactive Decay - An Analog.

    ERIC Educational Resources Information Center

    McGeachy, Frank

    1988-01-01

    Presents an analog of radioactive decay that allows the student to grasp the concept of half life and the exponential nature of the decay process. The analog is devised to use small, colored, plastic poker chips or counters. Provides the typical data and a graph which supports the analog. (YP)

  10. Radioactive Decay - An Analog.

    ERIC Educational Resources Information Center

    McGeachy, Frank

    1988-01-01

    Presents an analog of radioactive decay that allows the student to grasp the concept of half life and the exponential nature of the decay process. The analog is devised to use small, colored, plastic poker chips or counters. Provides the typical data and a graph which supports the analog. (YP)

  11. The Analogical Mind.

    ERIC Educational Resources Information Center

    Holyoak, Keith J.; Thagard, Paul

    1997-01-01

    The use of analogy in human thinking is examined from the perspective of a multiconstraint theory that postulates similarity, structure, and purpose as three kinds of constraints. The theory has been implemented in computational simulations of the analogical human mind using the Analogical Mapping by Constraint Satisfaction (ACME) model. (SLD)

  12. Fragmentation in isotopic and isobaric systems as probe of density dependence of nuclear symmetry energy

    NASA Astrophysics Data System (ADS)

    Kaur, Mandeep; Gautam, Sakshi; Puri, Rajeev K.

    2016-11-01

    We probe the density-dependent behavior of symmetry energy using the yield of various fragments in central collisions of various isotopic and isobaric colliding pairs. We calculate the yields of free nucleons, light charged particles and intermediate mass fragments in neutron-rich colliding systems as well as the ratio of relative yields of above fragments and free nucleons. Our findings reveal that the ratio of relative yield of light charged particles poses better candidate to probe the density dependence of nuclear symmetry energy.

  13. Characterization of the vanadium-nitrogen system with nitrogen pressure isobars.

    SciTech Connect

    Wang, W.-E.; Kim, Y. S.; Hong, H. S.; Engineering Division; Univ. of California

    2000-01-01

    The partial thermodynamic functions of the V-N system from V to VN over the temperature range 1000 to 2100 K have been investigated. The discrepancies among the pressure-composition-temperature (p-C-T) relationships in the {delta}-VN single-phase region have been resolved. The p-C-T relationships for other phases, where no data were available from the literature, have been established by applying the appropriate thermodynamic constraints and a modified form of Sieverts law. The results are presented as the nitrogen isobars superimposed on the phase diagram.

  14. Effect of isospin dependence of radius on transverse flow and fragmentation in isobaric pairs

    NASA Astrophysics Data System (ADS)

    Gautam, Sakshi

    2013-11-01

    We study the role of nuclear structure effects through radius in reaction dynamics via transverse flow and multifragmentation of isobaric colliding pairs. Our study reveals that isospin-dependent radius [proposed by Royer and Rousseau [Eur. Phys. J. A10.1140/epja/i2008-10745-8 42, 541 (2009)] has significant effect towards isospin effects. The collective flow behavior and fragmentation pattern of neutron-rich system with respect to neutron-deficient system is found to get reversed with isospin-dependent radius compared to that with liquid drop radius.

  15. Isobaric vapor-liquid equilibria in the system methyl propanoate + n-butyl alcohol

    SciTech Connect

    Susial, P.; Ortega, J. . Lab. de Termodinamica y Fisicoquimica)

    1993-10-01

    Isobaric vapor-liquid equilibria were determined at 74.66, 101.32, and 127.99 kPa for binary mixtures containing methyl propanoate + n-butyl alcohol by using a dynamic still with vapor and liquid circulation. No azeotrope was detected. The data were found to be thermodynamically consistent according to the point to point test. Application of the group-contribution models ASOG, UNIFAC, and modified UNIFAC to the activity coefficients at the three pressures studied gives average errors of less than 10%, 11%, and 3%, respectively.

  16. Preprocessing Significantly Improves the Peptide/Protein Identification Sensitivity of High-resolution Isobarically Labeled Tandem Mass Spectrometry Data*

    PubMed Central

    Sheng, Quanhu; Li, Rongxia; Dai, Jie; Li, Qingrun; Su, Zhiduan; Guo, Yan; Li, Chen; Shyr, Yu; Zeng, Rong

    2015-01-01

    Isobaric labeling techniques coupled with high-resolution mass spectrometry have been widely employed in proteomic workflows requiring relative quantification. For each high-resolution tandem mass spectrum (MS/MS), isobaric labeling techniques can be used not only to quantify the peptide from different samples by reporter ions, but also to identify the peptide it is derived from. Because the ions related to isobaric labeling may act as noise in database searching, the MS/MS spectrum should be preprocessed before peptide or protein identification. In this article, we demonstrate that there are a lot of high-frequency, high-abundance isobaric related ions in the MS/MS spectrum, and removing isobaric related ions combined with deisotoping and deconvolution in MS/MS preprocessing procedures significantly improves the peptide/protein identification sensitivity. The user-friendly software package TurboRaw2MGF (v2.0) has been implemented for converting raw TIC data files to mascot generic format files and can be downloaded for free from https://github.com/shengqh/RCPA.Tools/releases as part of the software suite ProteomicsTools. The data have been deposited to the ProteomeXchange with identifier PXD000994. PMID:25435543

  17. Analog Frame Store Memory.

    DTIC Science & Technology

    1980-01-15

    information in analog form for periods up to ten (i0)seconds. The storage element is a state-of-the-art monolithic charge coupled device (CCD) which...Analog Field Storage Device The Analog Field Storage Device is a solid state monolithic array operating on the "charge coupled" principle. It consists...the implementation of the corrective action. A three-month slip in delivery of the full system will result with integration test taking place in June

  18. Isobaric Melt Productivity of Peridotite: Constraints from Simple and Complex Systems

    NASA Astrophysics Data System (ADS)

    Matzen, A.; Baker, M.; Stolper, E.

    2006-12-01

    Isobaric melt productivity, (dF/dT)P, is an important term in the expression for isentropic melt productivity, (dF/dP)S. Theoretical analysis [1] suggests that (dF/dT)P is low near the fertile peridotite solidus and increases with increasing melt fraction, F, but experimental studies on natural peridotite bulk compositions yield conflicting results; this ambiguity may reflect difficulty in achieving equilibrium, analyzing low-degree melts, and/or calculating F near the solidus. Five component systems based on CaO-MgO-Al2O3- SiO2 plus one of FeO, Na2O, or K2O capture much of the complexity of natural peridotites but are simple enough to allow detailed characterization of melting relations without resorting to rigorous thermodynamic modeling. We used parameterizations of solid and liquid compositions as functions of T and P in the systems CMASK [2], CMASNa [3], and CMASFe [4] to calculate F (by wt) of model peridotite compositions by mass balance. The selected bulk composition for each system maximized the range in F over which liquid coexists with ol+opx+cpx and either sp or pl (depending on P); F varied up to 0.2. For sp-lherzolite (lherz) at F=0.005, calculated (dF/dT)P for CMASK, CMASNa, and CMASFe are 0.00012, 0.00082, and 0.048/°C. In both CMASK and CMASNa, productivity increases dramatically with increasing F yielding strongly concave down curves (semi-log plot). CMASFe shows a limited increase in (dF/dT)P with increasing F. For pl- saturated melts, (dF/dT)P in CMASNa shows, like CMASFe, limited variation with increasing F and similar productivities. We also parameterized liquid and solid compositions in CMASCrK [5] and calculated F as a function of T. At F=0.005, productivity is nearly identical to that of CMASK but with increasing F, (dF/dT)P levels off and more closely tracks the variation shown by CMASNa (sp lherz); i.e., productivity does not reach the high values found in CMASK at high F. As discussed in [1], (dF/dT)P is inversely proportional to the

  19. Nonvolatile Analog Memory

    NASA Technical Reports Server (NTRS)

    MacLeod, Todd C. (Inventor)

    2007-01-01

    A nonvolatile analog memory uses pairs of ferroelectric field effect transistors (FFETs). Each pair is defined by a first FFET and a second FFET. When an analog value is to be stored in one of the pairs, the first FFET has a saturation voltage applied thereto, and the second FFET has a storage voltage applied thereto that is indicative of the analog value. The saturation and storage voltages decay over time in accordance with a known decay function that is used to recover the original analog value when the pair of FFETs is read.

  20. Analog synthetic biology.

    PubMed

    Sarpeshkar, R

    2014-03-28

    We analyse the pros and cons of analog versus digital computation in living cells. Our analysis is based on fundamental laws of noise in gene and protein expression, which set limits on the energy, time, space, molecular count and part-count resources needed to compute at a given level of precision. We conclude that analog computation is significantly more efficient in its use of resources than deterministic digital computation even at relatively high levels of precision in the cell. Based on this analysis, we conclude that synthetic biology must use analog, collective analog, probabilistic and hybrid analog-digital computational approaches; otherwise, even relatively simple synthetic computations in cells such as addition will exceed energy and molecular-count budgets. We present schematics for efficiently representing analog DNA-protein computation in cells. Analog electronic flow in subthreshold transistors and analog molecular flux in chemical reactions obey Boltzmann exponential laws of thermodynamics and are described by astoundingly similar logarithmic electrochemical potentials. Therefore, cytomorphic circuits can help to map circuit designs between electronic and biochemical domains. We review recent work that uses positive-feedback linearization circuits to architect wide-dynamic-range logarithmic analog computation in Escherichia coli using three transcription factors, nearly two orders of magnitude more efficient in parts than prior digital implementations.

  1. Analog without fear

    NASA Technical Reports Server (NTRS)

    Delagrange, A. D.

    1977-01-01

    Analog circuitry, also referred to as Linear, has been nearly run over by the digital/computer bandwagon. This is unfortunate because tremendous advances are being made in the field of analog integrated circuitry. Each year's progress raises the state-of-the-art, bringing achievements not possible even the year before. Many of the traditional prejudices against analog circuitry are no longer valid. This report attempts to summarize what is available now and what can (and can't) be done with analog integrated circuitry.

  2. Simultaneous quantitative analysis of isobars by tandem mass spectrometry from unresolved chromatographic peaks.

    PubMed

    Kushnir, Mark M; Rockwood, Alan L; Nelson, Gordon J

    2004-05-01

    A method was developed for the simultaneous quantitation of isobars from unresolved chromatographic peaks. The method is based on differences in branching ratios of ion abundances in their tandem mass spectra and an assumption that the product ion mass spectra of a mixture can be considered as a linear combination of the spectra of individual constituents. We present analytical equations and a matrix-based approach for deconvoluting the concentration of individual components from the total peak intensity for two and three isobars and also a matrix-based generalization to any number of compounds. The feasibility of the simultaneous analysis of mixtures containing two compounds was assessed. The approach was evaluated for the analysis of structural isomers of methylmalonic and succinic acids in human plasma and urine samples for a group of 270 samples. The linear regression equation, standard error and correlation coefficient for the agreement with a traditional method utilizing chromatographic separation of the isomers were y = 0.999x - 0.005, 0.024 micro mol l(-1), and 0.985, respectively. The utility of a spectral contrast angle as a predictor of analysis feasibility was evaluated.

  3. Isobaric yield ratios and the symmetry energy in heavy-ion reactions near the Fermi energy

    SciTech Connect

    Huang, M.; Chen, Z.; Kowalski, S.; Ma, Y. G.; Wada, R.; Hagel, K.; Barbui, M.; Bottosso, C.; Materna, T.; Natowitz, J. B.; Qin, L.; Rodrigues, M. R. D.; Sahu, P. K.; Keutgen, T.; Bonasera, A.; Wang, J.

    2010-04-15

    The relative isobaric yields of fragments produced in a series of heavy-ion-induced multifragmentation reactions have been analyzed in the framework of a modified Fisher model, primarily to determine the ratio of the symmetry energy coefficient to the temperature, a{sub sym}/T, as a function of fragment mass A. The extracted values increase from 5 to approx16 as A increases from 9 to 37. These values have been compared to the results of calculations using the antisymmetrized molecular dynamics (AMD) model together with the statistical decay code gemini. The calculated ratios are in good agreement with those extracted from the experiment. In contrast, the values extracted from the ratios of the primary isobars from the AMD model calculation are approx4 to 5 and show little variation with A. This observation indicates that the value of the symmetry energy coefficient derived from final fragment observables may be significantly different than the actual value at the time of fragment formation. The experimentally observed pairing effect is also studied within the same simulations. The Coulomb coefficient is also discussed.

  4. Isobaric vapor-liquid equilibrium for methyldichlorosilane-dimethyldichlorosilane-benzene system*

    PubMed Central

    Qiu, Zu-min; Xie, Xin-liang; Yu, Shu-xian; Chen, Wen-you; Xie, Feng-xia; Liu, Juan

    2005-01-01

    The elucidation of vapor-liquid equilibrium (VLE) of the halogenated silane was necessary for the production of silicon derivatives, especially for methylvinyldichlorosilane, due to the lack of the relevant reports. Isobaric VLE for the system methyldichlorosilane-dimethyldichlorosilane-benzene and isobaric VLE of the three binary systems were measured with a new pump-ebulliometer at the pressure of 101.325 kPa. These binary compositions of the equilibrium vapor were calculated according to the Q function of molar excess Gibbs energy by the indirect method and the resulted VLE data agreed well with the thermodynamic consistency. Moreover, the experimental data were correlated with the Wilson, NRTL, Margules and van Laar equations by means of the least-squares fit, the acquired optimal interaction parameters were fitted to experimental vapor-liquid equilibrium data for binary systems. The binary parameters of Wilson equation were also used to calculate the bubble point temperature and the vapor phase composition for the ternary mixtures without any additional adjustment. The predicted vapor-liquid equilibrium for the ternary system was in a good agreement with the experimental results. The VLE of binary and multilateral systems provided essential theory for the production of the halogenated silane. PMID:16187419

  5. Texture evolution during isothermal, isostrain, and isobaric loading of polycrystalline shape memory NiTi

    NASA Astrophysics Data System (ADS)

    Nicholson, D. E.; Padula, S. A.; Benafan, O.; Vaidyanathan, R.

    2017-06-01

    In situ neutron diffraction was used to provide insights into martensite variant microstructures during isothermal, isobaric, and isostrain loading in shape memory NiTi. The results show that variant microstructures were equivalent for the corresponding strain, and more importantly, the reversibility and equivalency were immediately evident in variant microstructures that were first formed isobarically but then reoriented to near random self-accommodated microstructures following isothermal deformation. Variant microstructures formed isothermally were not significantly affected by a subsequent thermal cycle under constant strain. In all loading cases considered, the resulting variant microstructure correlated with strain and did not correlate with stress. Based on the ability to select a variant microstructure for a given strain despite thermomechanical loading history, the results demonstrated here can be obtained by following any sequence of thermomechanical loading paths over multiple cycles. Thus, for training shape memory alloys (repeating thermomechanical cycling to obtain the desired variant microstructure), optimal paths can be selected so as to minimize the number of training cycles required, thereby increasing the overall stability and fatigue life of these alloys in actuator or medical applications.

  6. Zr/Nb isobar separation experiment for future 93Zr AMS measurement

    NASA Astrophysics Data System (ADS)

    Lu, W.; Anderson, T.; Bowers, M.; Bauder, W.; Collon, P.; Kutschera, W.; Kashiv, Y.; Lachner, J.; Martschini, M.; Ostdiek, K.; Robertson, D.; Schmitt, C.; Skulski, M.; Steier, P.

    2015-10-01

    93Zr (t1/2 = 1.6 Ma) is mostly produced by the main s-process in low-to-intermediate mass AGB stars. Large uncertainty exists in the current 92Zr(n,γ)93Zr Maxwellian Average cross section. This could have significant impact on nucleosynthesis calculations. Large amounts of 93Zr are also produced in nuclear reactors and pose long-term environmental radioactivity. Hence, measurement of 93Zr by the AMS is important for both fields above. We report here on progress in the development of AMS method to measure 93Zr. Compared with 98 MeV beam energy, Zr/Nb isobar position separation was improved using 155.2 MeV beam energy and Gas-Filled Magnet. Energy loss measurement with increased beam energy inside the detector indicates that higher beam energy can improve isobar energy loss separation. A chemical procedure to reduce the Nb content in Zr samples has been developed and tested. It reduces the 93Nb content by a factor of 1000.

  7. Isobaric yield ratios in heavy-ion reactions, and symmetry energy of neutron-rich nuclei at intermediate energies

    NASA Astrophysics Data System (ADS)

    Ma, Chun-Wang; Wang, Fang; Ma, Yu-Gang; Jin, Chan

    2011-06-01

    The isobaric yield ratios of the fragments produced in the neutron-rich Ca48 and Ni64 projectile fragmentation are analyzed in the framework of a modified Fisher model. The correlations between the isobaric yield ratios (R) and the energy coefficients in the Weiszäcker-Beth semiclassical mass formula (the symmetry-energy term asym, the Coulomb-energy term ac, and the pairing-energy term ap) and the difference between the chemical potentials of the neutron and proton (μn-μp) are investigated. Simple correlations between (μn-μp)/T, ac/T, asym/T, and ap/T (where T is the temperature), and lnR are obtained. It is suggested that (μn-μp)/T, ac/T, asym/T, and ap/T of neutron-rich nuclei can be extracted using isobaric yield ratios for heavy-ion collisions at intermediate energies.

  8. Polymorphs of 1,1-diamino-2,2-dinitroethene (FOX-7): Isothermal compression versus isobaric heating

    NASA Astrophysics Data System (ADS)

    Dreger, Z. A.; Tao, Y.; Gupta, Y. M.

    2013-10-01

    Raman spectroscopy was used to examine polymorphic changes in 1,1-diamino-2,2-dinitroethene (FOX-7) single crystals under: isothermal compression to 15 GPa and isobaric heating to 500 K. Changes in the Raman spectra were observed at ˜2.0 and ˜4.5 GPa, and at ˜390 K and ˜450 K. These onsets are in general accord with previously reported onsets from IR measurements under isothermal compression and from X-ray diffraction measurements under isobaric heating, respectively. In contrast to recent suggestions, we show that the high pressure polymorphs have different vibrational structures, and likely different crystal structures, than the high temperature polymorphs.

  9. Isobaric molecular dynamics version of the generalized replica exchange method (gREM): Liquid–vapor equilibrium

    SciTech Connect

    Malolepsza, Edyta; Secor, Maxim; Keyes, Tom

    2015-09-23

    A prescription for sampling isobaric generalized ensembles with molecular dynamics is presented and applied to the generalized replica exchange method (gREM), which was designed for simulating first-order phase transitions. The properties of the isobaric gREM ensemble are discussed and a study is presented of the liquid-vapor equilibrium of the guest molecules given for gas hydrate formation with the mW water model. As a result, phase diagrams, critical parameters, and a law of corresponding states are obtained.

  10. Isobaric molecular dynamics version of the generalized replica exchange method (gREM): Liquid–vapor equilibrium

    DOE PAGES

    Malolepsza, Edyta; Secor, Maxim; Keyes, Tom

    2015-09-23

    A prescription for sampling isobaric generalized ensembles with molecular dynamics is presented and applied to the generalized replica exchange method (gREM), which was designed for simulating first-order phase transitions. The properties of the isobaric gREM ensemble are discussed and a study is presented of the liquid-vapor equilibrium of the guest molecules given for gas hydrate formation with the mW water model. As a result, phase diagrams, critical parameters, and a law of corresponding states are obtained.

  11. Analogies for Avogadro's Number.

    ERIC Educational Resources Information Center

    Poskozim, Paul S.; And Others

    1986-01-01

    Reviews analogies used to try to capture the concept of the magnitude of Avogadro's number, including analogies related to small/tiny objects, counting, people, water, and money. Also presents several new ones which are based on modern computers and printers. (JN)

  12. Challenges in Using Analogies

    ERIC Educational Resources Information Center

    Lin, Shih-Yin; Singh, Chandralekha

    2011-01-01

    Learning physics requires understanding the applicability of fundamental principles in a variety of contexts that share deep features. One way to help students learn physics is via analogical reasoning. Students can be taught to make an analogy between situations that are more familiar or easier to understand and another situation where the same…

  13. Analog synthetic biology

    PubMed Central

    Sarpeshkar, R.

    2014-01-01

    We analyse the pros and cons of analog versus digital computation in living cells. Our analysis is based on fundamental laws of noise in gene and protein expression, which set limits on the energy, time, space, molecular count and part-count resources needed to compute at a given level of precision. We conclude that analog computation is significantly more efficient in its use of resources than deterministic digital computation even at relatively high levels of precision in the cell. Based on this analysis, we conclude that synthetic biology must use analog, collective analog, probabilistic and hybrid analog–digital computational approaches; otherwise, even relatively simple synthetic computations in cells such as addition will exceed energy and molecular-count budgets. We present schematics for efficiently representing analog DNA–protein computation in cells. Analog electronic flow in subthreshold transistors and analog molecular flux in chemical reactions obey Boltzmann exponential laws of thermodynamics and are described by astoundingly similar logarithmic electrochemical potentials. Therefore, cytomorphic circuits can help to map circuit designs between electronic and biochemical domains. We review recent work that uses positive-feedback linearization circuits to architect wide-dynamic-range logarithmic analog computation in Escherichia coli using three transcription factors, nearly two orders of magnitude more efficient in parts than prior digital implementations. PMID:24567476

  14. Challenges in Using Analogies

    ERIC Educational Resources Information Center

    Lin, Shih-Yin; Singh, Chandralekha

    2011-01-01

    Learning physics requires understanding the applicability of fundamental principles in a variety of contexts that share deep features. One way to help students learn physics is via analogical reasoning. Students can be taught to make an analogy between situations that are more familiar or easier to understand and another situation where the same…

  15. Hydraulic Capacitor Analogy

    ERIC Educational Resources Information Center

    Baser, Mustafa

    2007-01-01

    Students have difficulties in physics because of the abstract nature of concepts and principles. One of the effective methods for overcoming students' difficulties is the use of analogies to visualize abstract concepts to promote conceptual understanding. According to Iding, analogies are consistent with the tenets of constructivist learning…

  16. Training in Analogical Reasoning.

    ERIC Educational Resources Information Center

    Alexander, Patricia A.; And Others

    1987-01-01

    Experiments involving a componential approach to analogy training were conducted with 36 fourth, 34 eighth, and 96 tenth graders. Results indicate a significant positive effect on all students' verbal analogy skills and no significant effect on fourth graders' inferential skills. In-class training and reading/language arts instruction implications…

  17. Hydraulic Capacitor Analogy

    ERIC Educational Resources Information Center

    Baser, Mustafa

    2007-01-01

    Students have difficulties in physics because of the abstract nature of concepts and principles. One of the effective methods for overcoming students' difficulties is the use of analogies to visualize abstract concepts to promote conceptual understanding. According to Iding, analogies are consistent with the tenets of constructivist learning…

  18. Analog pulse processor

    DOEpatents

    Wessendorf, Kurt O.; Kemper, Dale A.

    2003-06-03

    A very low power analog pulse processing system implemented as an ASIC useful for processing signals from radiation detectors, among other things. The system incorporates the functions of a charge sensitive amplifier, a shaping amplifier, a peak sample and hold circuit, and, optionally, an analog to digital converter and associated drivers.

  19. Evaluating the Efficacy of Tramadol as an Adjuvant to Intrathecal Isobaric Levobupivacaine for Elective Infraumbilical Surgeries.

    PubMed

    Singh, Dewan Roshan; Mohamed, Hajer; Krishnaveni, N; Nag, Kusha

    2017-01-01

    Long-acting local anesthetics are used in subarachnoid block to increase the duration of anesthesia. Adjuvants are added to improve the duration of analgesia. Randomized controlled trial was conducted in the Department of Anesthesiology in a tertiary care hospital. The objective of this study was to evaluate the efficacy of low-dose tramadol as an intrathecal adjuvant to levobupivacaine in terms of duration of analgesia, onset of sensory blockade, onset of motor blockade, and duration of motor blockade. After obtaining the Institutional Ethics Committee approval and informed consent, sixty patients posted for infraumbilical surgeries were recruited. Randomization was done using a sealed envelope technique. Patients were divided into two groups: LT received 3 ml of 0.5% isobaric levobupivacaine with tramadol 10 mg (0.2 ml) and LS received 3 ml of 0.5% isobaric levobupivacaine with 0.2 ml of normal saline. Duration of analgesia, onset of sensory blockade, and onset and duration of motor blockade were recorded. There was no statistical difference in demographic data between the two groups. The mean onset time of sensory blockade in Group LS was 12.7 ± 9.81 min and for Group LT was 12.9 ± 0.81 min, which was not statistically significant between two groups (P = 0.93). The mean onset time of motor blockade in Group LS was 13.4 ± 10 min and for Group LT was 14.4 ± 10 min, which was no statistically significant between the two groups (P = 0.71). The mean time duration of analgesia in Group LS was 170.3 ± 59 min and for LT was 198.9 ± 57.33 min. There was mild prolongation of analgesia in Group LT, but it was not statistically significant (P = 0.0615). The mean duration of motor blockade in Group LS was 170.23 ± 58 min and Group LT was 190.76 ± 4 min, which was not statistically significant between the two groups (P = 0.14). Low-dose tramadol as an adjuvant to isobaric intrathecal levobupivacaine does not prolong analgesia significantly.

  20. Evaluating the Efficacy of Tramadol as an Adjuvant to Intrathecal Isobaric Levobupivacaine for Elective Infraumbilical Surgeries

    PubMed Central

    Singh, Dewan Roshan; Mohamed, Hajer; Krishnaveni, N.; Nag, Kusha

    2017-01-01

    Background: Long-acting local anesthetics are used in subarachnoid block to increase the duration of anesthesia. Adjuvants are added to improve the duration of analgesia. Settings: Randomized controlled trial was conducted in the Department of Anesthesiology in a tertiary care hospital. Aims and Objectives: The objective of this study was to evaluate the efficacy of low-dose tramadol as an intrathecal adjuvant to levobupivacaine in terms of duration of analgesia, onset of sensory blockade, onset of motor blockade, and duration of motor blockade. Methodology: After obtaining the Institutional Ethics Committee approval and informed consent, sixty patients posted for infraumbilical surgeries were recruited. Randomization was done using a sealed envelope technique. Patients were divided into two groups: LT received 3 ml of 0.5% isobaric levobupivacaine with tramadol 10 mg (0.2 ml) and LS received 3 ml of 0.5% isobaric levobupivacaine with 0.2 ml of normal saline. Duration of analgesia, onset of sensory blockade, and onset and duration of motor blockade were recorded. Results: There was no statistical difference in demographic data between the two groups. The mean onset time of sensory blockade in Group LS was 12.7 ± 9.81 min and for Group LT was 12.9 ± 0.81 min, which was not statistically significant between two groups (P = 0.93). The mean onset time of motor blockade in Group LS was 13.4 ± 10 min and for Group LT was 14.4 ± 10 min, which was no statistically significant between the two groups (P = 0.71). The mean time duration of analgesia in Group LS was 170.3 ± 59 min and for LT was 198.9 ± 57.33 min. There was mild prolongation of analgesia in Group LT, but it was not statistically significant (P = 0.0615). The mean duration of motor blockade in Group LS was 170.23 ± 58 min and Group LT was 190.76 ± 4 min, which was not statistically significant between the two groups (P = 0.14). Conclusion: Low-dose tramadol as an adjuvant to isobaric intrathecal

  1. Meat analog: a review.

    PubMed

    Malav, O P; Talukder, S; Gokulakrishnan, P; Chand, S

    2015-01-01

    The health-conscious consumers are in search of nutritious and convenient food item which can be best suited in their busy life. The vegetarianism is the key for the search of such food which resembles the meat in respect of nutrition and sensory characters, but not of animal origin and contains vegetable or its modified form, this is the point when meat analog evolved out and gets shape. The consumers gets full satisfaction by consumption of meat analog due to its typical meaty texture, appearance and the flavor which are being imparted during the skilled production of meat analog. The supplement of protein in vegetarian diet through meat alike food can be fulfilled by incorporating protein-rich vegetative food grade materials in meat analog and by adopting proper technological process which can promote the proper fabrication of meat analog with acceptable meat like texture, appearance, flavor, etc. The easily available vegetables, cereals, and pulses in India have great advantages and prospects to be used in food products and it can improve the nutritional and functional characters of the food items. The various form and functional characters of food items are available world over and attracts the meat technologists and the food processors to bring some innovativeness in meat analog and its presentation and marketability so that the acceptability of meat analog can be overgrown by the consumers.

  2. Thermodynamic Quantities of Redlich-Kwong Gases in Isobaric Processes of Coexistence of Two Phases

    NASA Astrophysics Data System (ADS)

    Matsumoto, Akira

    2005-12-01

    The coexistence of gaseous and liquid phases in an isobaric process are investigated by applying the thermodynamic functions of the Redlich-Kwong equation. The boiling temperatures and the enthalpy changes of vaporization of 45 substances are obtained by numerical calculations. The results agree with the experimental data within a few percent for the 45 considered substances. Some thermodynamic quantities for C3H6 at 1 atm are calculated numerically as a function of T and drawn graphically. The Gibbs free energy indicates a polygonal line; entropy, volume and enthalpy jump from the liquid to the gaseous phase at the boiling point. The heat capacity does not diverge to infinity but shows a finite jump at the boiling point. This suggests that a first-order phase transition may occur at the boiling point.

  3. An ion guide laser ion source for isobar-suppressed rare isotope beams

    SciTech Connect

    Raeder, Sebastian Ames, Friedhelm; Bishop, Daryl; Bricault, Pierre; Kunz, Peter; Mjøs, Anders; Heggen, Henning; Lassen, Jens Teigelhöfer, Andrea

    2014-03-15

    Modern experiments at isotope separator on-line (ISOL) facilities like ISAC at TRIUMF often depend critically on the purity of the delivered rare isotope beams. Therefore, highly selective ion sources are essential. This article presents the development and successful on-line operation of an ion guide laser ion source (IG-LIS) for the production of ion beams free of isobaric contamination. Thermionic ions from the hot ISOL target are suppressed by an electrostatic potential barrier, while neutral radio nuclides effusing out are resonantly ionized by laser radiation within a quadrupole ion guide behind this barrier. The IG-LIS was developed through detailed thermal and ion optics simulation studies and off-line tests with stable isotopes. In a first on-line run with a SiC target a suppression of surface-ionized Na contaminants in the ion beam of up to six orders of magnitude was demonstrated.

  4. η′ meson photoproduction off nucleon in the isobar model

    SciTech Connect

    Saipudin, Salam, A.

    2016-04-19

    The recent high-precision data for the reaction γ p → pη′ at center-of-mass energies from near threshold up to 2.84 GeV is obtained by the CLAS collaboration at the Jefferson Laboratory [1] have been analyzed within an isobar model. The η′ photoproduction can be described quite well over the entire energy range of available data by considering S {sub 11} and P{sub 11} resonances, in addition to the nucleon s- and u-channel resonance contribution, also t-channel mesonic currents. For the resonances considered, our analysis we use masses and widths advocated by the Particle Data Group. We emphasize, that cross-section data alone are able to reproduce the value of resonance parameters and hadronic coupling constant.

  5. NIPTL-Novo: Non-isobaric peptide termini labeling assisted peptide de novo sequencing.

    PubMed

    Zhang, Shen; Shan, Yichu; Zhang, Shurong; Sui, Zhigang; Zhang, Lihua; Liang, Zhen; Zhang, Yukui

    2017-02-10

    A simple and effective de novo sequencing strategy assisted by non-isobaric peptide termini labeling, NIPTL-Novo, was established. The y-series ions and b-series ions of peptides can be clearly distinguished according to the different mass tags incorporated in N-terminus and C-terminus. This is helpful for improving the accuracy of peptide sequencing and increasing the sequencing speed. For the spectra commonly identified by both de novo sequencing and database searching software (Mascot or Maxquant), NIPTL-Novo gave identical result to more than 85% of these spectra. Furthermore, the quantitative profiling of the sample can be performed simultaneously along with de novo sequencing. Finally, this strategy can be applied to discover the peptides with potential mutation sites by combining with mass-defect based isotopic labeling.

  6. A new gas lesion syndrome in man, induced by 'isobaric gas counterdiffusion'

    NASA Technical Reports Server (NTRS)

    Lambertsen, C. J.; Idicula, J.

    1975-01-01

    Normal men have been found to develop pruritis and gas bubble lesions in the skin, and disruption of vestibular function, when breathing nitrogen or neon with oxygen while surrounded by helium at increased ambient pressure. This phenomenon, which occurs at stable ambient pressures, at 1 or many ATA, has been designated the isobaric gas counterdiffusion syndrome. In a series of analyses and experiments in vivo and in vitro the cause of the syndrome has been established as due to gas accumulation and development of gas bubbles in tissues as a result of differences in selective diffusivities, for various respired and ambient gases, in the tissue substances between capillary blood and the surrounding atmosphere. The phenomenon described in man is an initial stage of a process shown later in animals to progress to continuous, massive, lethal, intravascular gas embolization.

  7. A new gas lesion syndrome in man, induced by "isobaric gas counterdiffusion".

    PubMed

    Lambertsen, C J; Idicula, J

    1975-09-01

    Normal men have been found to develop pruritus and gas bubble lesions in the skin, and disruption of vestibular function, when breathing nitrogen or neon with oxygen while surrounded by helium at increased ambient pressure. This phenomenon, which occurs at stable ambient pressures, at 1 or many ATA, has been designated the "isobaric gas counterdiffusion syndrome." In a series of analyses and experiments in vivo and in vitro the cause of the syndrome has been established as due to gas accumulation and development of gas bubbles in tissues as a result of differences in selective diffusivities, for various respired and ambient gases, in the tissue substances between capillary blood and the surrounding atmosphere. The phenomenon here described in man is an initial stage of a process shown later in animals to progress to continuous, massive, lethal, intravascular gas embolization.

  8. Weather maps classification over Greek domain based on isobaric line patterns. A pattern recognition approach

    NASA Astrophysics Data System (ADS)

    Zagouras, Athanassios; Argiriou, Athanassios A.; Economou, George; Fotopoulos, Spiros; Flocas, Helena A.

    2013-11-01

    The paper presents a semi-supervised weather classification method based on 850-hPa isobaric level maps. A preprocessing step is employed, where isolines of geopotential height are extracted from weather map images via an image processing procedure. Α feature extraction stage follows where two techniques are applied. The first technique implements phase space reconstruction, and yields multidimensional delay distributions. The second technique is based on chain code representation of signals, from which histogram features are derived. Similarity measures are used to compare multidimensional data and the k-means algorithm is applied in the final stage. The method is applied over the area of Greece, and the resulting catalogues are compared to a subjective classification for this area. Numerical experiments with datasets derived from the European Meteorological Bulletin archives exhibit an up to 91 % accurate agreement with the subjective weather patterns.

  9. Electron attachment studies to musk ketone and high mass resolution anionic isobaric fragment detection

    NASA Astrophysics Data System (ADS)

    Mauracher, A.; Sulzer, P.; Alizadeh, E.; Denifl, S.; Ferreira da Silva, F.; Probst, M.; Märk, T. D.; Limão-Vieira, P.; Scheier, P.

    2008-11-01

    Gas phase electron attachment studies have been performed for musk ketone by means of a crossed electron-molecular beams experiment in an energy range from 0 to 15 eV with a resolution of ~70 meV. Additional measurements, utilizing a two-sector-field instrument, have been used to distinguish between possible isobaric products. Anion efficiency curves for 19 anions have been measured including a long-lived (metastable) non-dissociated parent anion which is formed at energies near 0 eV. Many of the dissociative electron attachment products observed at low energy arise from surprisingly complex reactions associated with multiple bond cleavages and structural and electronic rearrangement. The present results are compared with previous aromatic nitrocompounds studied in our laboratory recently. Particularly the close similarity of musk ketone and the explosive trinitrotoluene is of special interest.

  10. Structural Relaxation of 3-Dimensionally Confined Polymer Glasses: Isobaric versus Isochoric Glass Formation

    NASA Astrophysics Data System (ADS)

    Guo, Yunlong; Zhang, Chuan; Priestley, Rodney

    2011-03-01

    We have measured the glassy-state structural relaxation of aqueous suspended polystyrene (PS) nanoparticles and the corresponding silica-capped PS nanoparticles via modulated differential scanning calorimetry. Suspended and capped-PS nanoparticles undergo glass formation and subsequent physical aging under isobaric and isochoric conditions, respectively. To account for glass transition temperature (Tg) changes with confinement, physical aging measurements were performed at a constant value of Tg minus Ta, where Ta is the aging temperature. With deceasing diameter, aqueous suspended PS nanoparticles exhibited enhanced physical aging rates in comparison to bulk PS. At all values of Tg minus Ta investigated, capped-PS nanoparticles aged at reduced rates compared to the corresponding aqueous suspended PS nanoparticles. Due to differences in paths to glass formation, suspended and capped-PS nanoparticles aged to different apparent equilibrium states. We captured the physical aging behavior of all nanoparticles via the Tool, Narayanaswamy, and Moynihan (TNM) model of structural relaxation.

  11. Intrathecal hyperbaric versus isobaric bupivacaine for adult non-caesarean-section surgery: systematic review protocol

    PubMed Central

    Uppal, Vishal; Shanthanna, Harsha; Prabhakar, Christopher; McKeen, Dolores M

    2016-01-01

    Introduction Bupivacaine is the most commonly used local anaesthetic for spinal anaesthesia (SA). There are two forms of commercially available bupivacaine; isobaric bupivacaine (IB): a formulation with a specific gravity or density equal to cerebrospinal fluid, and hyperbaric bupivacaine (HB): a formulation with density heavier than cerebrospinal fluid. The difference in densities of the two available preparations is believed to affect the diffusion pattern that determines the effectiveness, spread and side-effect profile of bupivacaine. This systematic review will summarise the best available evidence regarding the effectiveness and safety on the use of HB compared with IB, when used to provide SA for surgery. Primarily, we will analyse the need for conversion to general anaesthesia. As secondary outcomes, we will compare the incidence of hypotension, incidence of nausea/vomiting, the onset time and duration of anaesthesia. Methods and analysis We will search key electronic databases using search strategy (1) injections, spinal OR intrathecal OR subarachnoid; (2) bupivacaine OR levobupivacaine; (3) hypobaric OR isobaric OR plain; (4) baricity. We will search MEDLINE, EMBASE and Cochrane databases, from their inception for randomised controlled trials, with no restrictions on language. Caesarean section surgery will be excluded. 2 reviewers will independently extract the data using a standardised form. Extracted items will include study characteristics, risk of bias domains, as per modified Cochrane risk of bias, participant disposition and study outcomes. We will conduct a meta-analysis for variables that can be compared across the studies. We will evaluate clinical heterogeneity by qualitatively appraising differences in study characteristics in participants, interventions and the outcomes assessed. We will report our findings as relative risks (dichotomous), and weighted mean differences (continuous) for individual outcomes, along with their 95% CIs. Ethics and

  12. A hierarchical statistical modeling approach to analyze proteomic isobaric tag for relative and absolute quantitation data.

    PubMed

    Zhou, Cong; Walker, Michael J; Williamson, Andrew J K; Pierce, Andrew; Berzuini, Carlo; Dive, Caroline; Whetton, Anthony D

    2014-02-15

    Isobaric tag for relative and absolute quantitation (iTRAQ) is a widely used method in quantitative proteomics. A robust data analysis strategy is required to determine protein quantification reliability, i.e. changes due to biological regulation rather than technical variation, so that proteins that are differentially expressed can be identified. Samples were created by mixing 5, 10, 15 and 20 μg Escherichia coli cell lysate with 100 μg of cell lysate from mouse, corresponding to expected relative fold changes of one for mouse proteins and from 0.25 to 4 for E.coli proteins. Relative quantification was carried out using eight channel isobaric tagging with iTRAQ reagent, and proteins were identified using a TripleTOF 5600 mass spectrometer. Technical variation inherent in this iTRAQ dataset was systematically investigated. A hierarchical statistical model was developed to use quantitative information at peptide level and protein level simultaneously to estimate variation present in each individual peptide and protein. A novel data analysis strategy for iTRAQ, denoted in short as WHATraq, was subsequently proposed with its performance evaluated by the proportion of E.coli proteins that are successfully identified as differentially expressed. Compared with two benchmark data analysis strategies WHATraq was able to identify at least 62.8% more true positive proteins that are differentially expressed. Further validated using a biological iTRAQ dataset including multiple biological replicates from varied murine cell lines, WHATraq performed consistently and identified 375% more proteins as being differentially expressed among different cell lines than the other data analysis strategies.

  13. Geological, isothermal, and isobaric 3-D model construction in early stage of geothermal exploration

    NASA Astrophysics Data System (ADS)

    Saputra, M. P.; Suryantini; Catigtig, D.; Regandara, R.; Asnin, S. N.; Pratama, A. B.

    2016-09-01

    Construction of geology, thermal anomaly and pressure distribution of a geothermal system in the early stage of exploration where data is limited is described using a 3-D software, Leapfrog Geothermal. The geological 3-D model was developed from a topographic map (derived from DEM data), geological map and literature studies reported in an early geological survey. The isothermal 3-D model was constructed using reservoir temperature estimation from geothermometry calculated from chemical analyses on surface manifestations, available shallow gradient temperature hole data and the normal gradient temperature (3°C/100m) for a nonthermal area. The isobaric 3-D model was built using hydrostatic pressure where the hydrostatic pressure is determined by the product of the fluid density, acceleration due to gravity, and depth. Fluid density is given by saturated liquid density as a function of temperature. There are some constraints on the modelling result such as (1) within the predicted reservoir, the geothermal gradient is not constant but continues to increase, thus, creating an anomalously high temperature at depth, and (2) the lithology model is made by interpolating and extrapolating cross-sections whereas usually only two to three geology sections were available for this study. Hence, the modeller must understand the geology. An additional cross section was developed by the modeller which may not be as suitable as the geologist constructed sections. The results of this study can be combined with geophysical data such as gravity, geomagnetic, micro-tremor and resistivity data. The combination of geological, geochemical, isothermal, isobaric and geophysical data could be used in (1) estimating the geometry and size of the geothermal reservoir, (2) predicting the depth of top reservoir, and (3) creating well prognosis for exploration and production wells.

  14. Quantitation of isobaric phosphatidylcholine species in human plasma using a hybrid quadrupole linear ion-trap mass spectrometer.

    PubMed

    Zacek, Petr; Bukowski, Michael; Rosenberger, Thad A; Picklo, Matthew

    2016-12-01

    Phosphatidylcholine (PC) species in human plasma are used as biomarkers of disease. PC biomarkers are often limited by the inability to separate isobaric PCs. In this work, we developed a targeted shotgun approach for analysis of isobaric and isomeric PCs. This approach is comprised of two MS methods: a precursor ion scanning (PIS) of mass m/z 184 in positive mode (PIS m/z +184) and MS(3) fragmentation in negative mode, both performed on the same instrument, a hybrid triple quadrupole ion-trap mass spectrometer. The MS(3) experiment identified the FA composition and the relative abundance of isobaric and sn-1, sn-2 positional isomeric PC species, which were subsequently combined with absolute quantitative data obtained by PIS m/z +184 scan. This approach was applied to the analysis of a National Institute of Standards and Technology human blood plasma standard reference material (SRM 1950). We quantified more than 70 PCs and confirmed that a majority are present in isobaric and isomeric mixtures. The FA content determined by this method was comparable to that obtained using GC with flame ionization detection, supporting the quantitative nature of this MS method. This methodology will provide more in-depth biomarker information for clinical and mechanistic studies.

  15. Quantitation of isobaric phosphatidylcholine species in human plasma using a hybrid quadrupole linear ion-trap mass spectrometer[S

    PubMed Central

    Zacek, Petr; Bukowski, Michael; Rosenberger, Thad A.; Picklo, Matthew

    2016-01-01

    Phosphatidylcholine (PC) species in human plasma are used as biomarkers of disease. PC biomarkers are often limited by the inability to separate isobaric PCs. In this work, we developed a targeted shotgun approach for analysis of isobaric and isomeric PCs. This approach is comprised of two MS methods: a precursor ion scanning (PIS) of mass m/z 184 in positive mode (PIS m/z +184) and MS3 fragmentation in negative mode, both performed on the same instrument, a hybrid triple quadrupole ion-trap mass spectrometer. The MS3 experiment identified the FA composition and the relative abundance of isobaric and sn-1, sn-2 positional isomeric PC species, which were subsequently combined with absolute quantitative data obtained by PIS m/z +184 scan. This approach was applied to the analysis of a National Institute of Standards and Technology human blood plasma standard reference material (SRM 1950). We quantified more than 70 PCs and confirmed that a majority are present in isobaric and isomeric mixtures. The FA content determined by this method was comparable to that obtained using GC with flame ionization detection, supporting the quantitative nature of this MS method. This methodology will provide more in-depth biomarker information for clinical and mechanistic studies. PMID:27688258

  16. Isobaric protein-level labeling strategy for serum glycoprotein quantification analysis by liquid chromatography-tandem mass spectrometry.

    PubMed

    Nie, Song; Lo, Andy; Zhu, Jianhui; Wu, Jing; Ruffin, Mack T; Lubman, David M

    2013-06-04

    While peptide-level labeling using isobaric tag reagents has been widely applied for quantitative proteomics experiments, there are comparatively few reports of protein-level labeling. Intact protein labeling could be broadly applied to quantification experiments utilizing protein-level separations or enrichment schemes. Here, protein-level isobaric labeling was explored as an alternative strategy to peptide-level labeling for serum glycoprotein quantification. Labeling and digestion conditions were optimized by comparing different organic solvents and enzymes. Digestions with Asp-N and trypsin were found highly complementary; combining the results enabled quantification of 30% more proteins than either enzyme alone. Three commercial reagents were compared for protein-level labeling. Protein identification rates were highest with iTRAQ 4-plex when compared to TMT 6-plex and iTRAQ 8-plex using higher-energy collisional dissociation on an Orbitrap Elite mass spectrometer. The compatibility of isobaric protein-level labeling with lectin-based glycoprotein enrichment was also investigated. More than 74% of lectin-bound labeled proteins were known glycoproteins, which was similar to results from unlabeled and peptide-level labeled serum samples. Finally, protein-level and peptide-level labeling strategies were compared for serum glycoprotein quantification. Isobaric protein-level labeling gave comparable identification levels and quantitative precision to peptide-level labeling.

  17. Challenges in Using Analogies

    NASA Astrophysics Data System (ADS)

    Lin, Shih-Yin; Singh, Chandralekha

    2011-11-01

    Learning physics requires understanding the applicability of fundamental principles in a variety of contexts that share deep features.1-7 One way to help students learn physics is via analogical reasoning. Students can be taught to make an analogy between situations that are more familiar or easier to understand and another situation where the same physics principle is involved but that is more difficult to handle. Here, we examine introductory physics students' ability to use analogies in solving problems involving Newton's second law. Students enrolled in an algebra-based introductory physics course were given a solved problem involving tension in a rope and were then asked to solve another problem for which the physics is very similar but involved a frictional force. They were asked to point out the similarities between the two problems and then use the analogy to solve the friction problem.

  18. Fatty acid analogs

    DOEpatents

    Elmaleh, David R.; Livni, Eli

    1985-01-01

    In one aspect, a radioactively labeled analog of a fatty acid which is capable of being taken up by mammalian tissue and which exhibits an in vivo beta-oxidation rate below that with a corresponding radioactively labeled fatty acid.

  19. FGF growth factor analogs

    DOEpatents

    Zamora, Paul O [Gaithersburg, MD; Pena, Louis A [Poquott, NY; Lin, Xinhua [Plainview, NY; Takahashi, Kazuyuki [Germantown, MD

    2012-07-24

    The present invention provides a fibroblast growth factor heparin-binding analog of the formula: ##STR00001## where R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, X, Y and Z are as defined, pharmaceutical compositions, coating compositions and medical devices including the fibroblast growth factor heparin-binding analog of the foregoing formula, and methods and uses thereof.

  20. Comparison between intrathecal isobaric ropivacaine-fentanyl and bupivacaine-fentanyl in elective infraumbilical orthopedic surgery: A randomized controlled study

    PubMed Central

    Layek, Amitava; Maitra, Souvik; Gozi, Nitish K; Bhattacharjee, Sulagna; Pal, Sugata; Sen, Suvadeep; Hazra, Avijit

    2015-01-01

    Background and Aims: We aimed to evaluate and compare the block characteristics and duration of analgesia of intrathecal isobaric ropivacaine-fentanyl and bupivacaine-fentanyl combination in adult patients undergoing lower limb orthopedic surgery. Material and Methods: Seventy-four American Society of Anesthesiologists’ I and II adult patients undergoing lower limb orthopedic surgery under subarachnoid block were randomized to receive either 3 ml 0.5% isobaric ropivacaine and 25 mcg fentanyl (Group R) or 3 ml 0.5% isobaric bupivacaine and 25 mcg fentanyl (Group B). The hemodynamic profiles, maximum upper level of sensory block height, time to reach peak block height, two dermatome regression time, and duration of motor block were recorded. Results: There was no statistically significant difference regarding the hemodynamic parameters between the groups. The median (range) peak sensory block height was T7 (T4-T9) in Group R and T7 (T4-T10) in Group B. Time to reach peak block height (13.2 ± 2.3 min in Group R vs. 13.7 ± 2.2 min in Group B; P = 0.385) was similar between the groups. Two dermatome regression time in sensory block (median 120 min vs. 85 min; P < 0.001) and duration of motor block (median 245 min vs. 150 min; P < 0.001) was significantly higher in Group B. The duration of analgesia (median 360 min vs. 245 min; P < 0.001) was significantly higher in the bupivacaine group. Conclusion: Intrathecal isobaric bupivacaine-fentanyl combination produces a significantly longer duration of analgesia, sensory block and motor block than isobaric ropivacaine-fentanyl combination. As ropivacaine has a shorter duration of sensory and motor block, it may be preferred in day care surgery. PMID:26702216

  1. Electrical Circuits and Water Analogies

    ERIC Educational Resources Information Center

    Smith, Frederick A.; Wilson, Jerry D.

    1974-01-01

    Briefly describes water analogies for electrical circuits and presents plans for the construction of apparatus to demonstrate these analogies. Demonstrations include series circuits, parallel circuits, and capacitors. (GS)

  2. Electrical Circuits and Water Analogies

    ERIC Educational Resources Information Center

    Smith, Frederick A.; Wilson, Jerry D.

    1974-01-01

    Briefly describes water analogies for electrical circuits and presents plans for the construction of apparatus to demonstrate these analogies. Demonstrations include series circuits, parallel circuits, and capacitors. (GS)

  3. Flow cytomeric measurement of DNA and incorporated nucleoside analogs

    DOEpatents

    Dolbeare, Frank A.; Gray, Joe W.

    1989-01-01

    A method is provided for simultaneously measuring total cellular DNA and incorporated nucleoside analog. The method entails altering the cellular DNA of cells grown in the presence of a nucleoside analog so that single stranded and double stranded portions are present. Separate stains are used against the two portions. An immunochemical stain is used against the single stranded portion to provide a measure of incorporated nucleoside analog, and a double strand DNA-specific stain is used against the double stranded portion to simultaneously provide a measure of total cellular DNA. The method permits rapid flow cytometric analysis of cell populations, rapid identification of cycling and noncycling subpopulations, and determination of the efficacy of S phase cytotoxic anticancer agents.

  4. Digital and analog communication systems

    NASA Technical Reports Server (NTRS)

    Shanmugam, K. S.

    1979-01-01

    The book presents an introductory treatment of digital and analog communication systems with emphasis on digital systems. Attention is given to the following topics: systems and signal analysis, random signal theory, information and channel capacity, baseband data transmission, analog signal transmission, noise in analog communication systems, digital carrier modulation schemes, error control coding, and the digital transmission of analog signals.

  5. Analogical Reasoning in Geometry Education

    ERIC Educational Resources Information Center

    Magdas, Ioana

    2015-01-01

    The analogical reasoning isn't used only in mathematics but also in everyday life. In this article we approach the analogical reasoning in Geometry Education. The novelty of this article is a classification of geometrical analogies by reasoning type and their exemplification. Our classification includes: analogies for understanding and setting a…

  6. Electrical analogous in viscoelasticity

    NASA Astrophysics Data System (ADS)

    Ala, Guido; Di Paola, Mario; Francomano, Elisa; Li, Yan; Pinnola, Francesco P.

    2014-07-01

    In this paper, electrical analogous models of fractional hereditary materials are introduced. Based on recent works by the authors, mechanical models of materials viscoelasticity behavior are firstly approached by using fractional mathematical operators. Viscoelastic models have elastic and viscous components which are obtained by combining springs and dashpots. Various arrangements of these elements can be used, and all of these viscoelastic models can be equivalently modeled as electrical circuits, where the spring and dashpot are analogous to the capacitance and resistance, respectively. The proposed models are validated by using modal analysis. Moreover, a comparison with numerical experiments based on finite difference time domain method shows that, for long time simulations, the correct time behavior can be obtained only with modal analysis. The use of electrical analogous in viscoelasticity can better reveal the real behavior of fractional hereditary materials.

  7. Analog Optical Links

    NASA Astrophysics Data System (ADS)

    Cox, Charles H., III

    2004-05-01

    Unlike books that focus on the devices used in links, such as lasers and photodiodes, among others, this text focuses on the next level. It covers the collection of devices that form a link, how the individual device performance affects the link performance, or the reverse. Analog links are used for the distribution of cable TV signals, and in conveying the signals to and from antennas (so called antenna remoting). The design of analog links differs significantly from digital links which are primarily used in telecommunications.

  8. Caffeine analogs: biomedical impact.

    PubMed

    Daly, J W

    2007-08-01

    Caffeine, widely consumed in beverages, and many xanthine analogs have had a major impact on biomedical research. Caffeine and various analogs, the latter designed to enhance potency and selectivity toward specific biological targets, have played key roles in defining the nature and role of adenosine receptors, phosphodiesterases, and calcium release channels in physiological processes. Such xanthines and other caffeine-inspired heterocycles now provide important research tools and potential therapeutic agents for intervention in Alzheimer's disease, asthma, cancer, diabetes, and Parkinson's disease. Such compounds also have activity as analgesics, antiinflammatories, antitussives, behavioral stimulants, diuretics/natriuretics, and lipolytics. Adverse effects can include anxiety, hypertension, certain drug interactions, and withdrawal symptoms.

  9. Type II shell evolution in A = 70 isobars from the N ≥ 40 island of inversion

    NASA Astrophysics Data System (ADS)

    Morales, A. I.; Benzoni, G.; Watanabe, H.; Tsunoda, Y.; Otsuka, T.; Nishimura, S.; Browne, F.; Daido, R.; Doornenbal, P.; Fang, Y.; Lorusso, G.; Patel, Z.; Rice, S.; Sinclair, L.; Söderström, P.-A.; Sumikama, T.; Wu, J.; Xu, Z. Y.; Yagi, A.; Yokoyama, R.; Baba, H.; Avigo, R.; Bello Garrote, F. L.; Blasi, N.; Bracco, A.; Camera, F.; Ceruti, S.; Crespi, F. C. L.; de Angelis, G.; Delattre, M.-C.; Dombradi, Zs.; Gottardo, A.; Isobe, T.; Kojouharov, I.; Kurz, N.; Kuti, I.; Matsui, K.; Melon, B.; Mengoni, D.; Miyazaki, T.; Modamio-Hoybjor, V.; Momiyama, S.; Napoli, D. R.; Niikura, M.; Orlandi, R.; Sakurai, H.; Sahin, E.; Sohler, D.; Schaffner, H.; Taniuchi, R.; Taprogge, J.; Vajta, Zs.; Valiente-Dobón, J. J.; Wieland, O.; Yalcinkaya, M.

    2017-02-01

    The level structures of 70Co and 70Ni, populated from the β decay of 70Fe, have been investigated using β-delayed γ-ray spectroscopy following in-flight fission of a 238U beam. The experimental results are compared to Monte-Carlo Shell-Model calculations including the pf +g9/2 +d5/2 orbitals. The strong population of a (1+) state at 274 keV in 70Co is at variance with the expected excitation energy of ∼1 MeV from near spherical single-particle estimates. This observation indicates a dominance of prolate-deformed intruder configurations in the low-lying levels, which coexist with the normal near spherical states. It is shown that the β decay of the neutron-rich A = 70 isobars from the new island of inversion to the Z = 28 closed-shell regime progresses in accordance with a newly reported type of shell evolution, the so-called Type II, which involves many particle-hole excitations across energy gaps.

  10. Differentiation of hydroxyproline isomers and isobars in peptides by tandem mass spectrometry.

    PubMed

    Kassel, D B; Biemann, K

    1990-08-01

    The isomeric 3- and 4-hydroxyprolines are isobaric with the isomers leucine and isoleucine, and all four have, therefore, the same "residue mass" of 113. Secondary fragmentation processes were found that differentiate the hydroxyproline isomers from each other and from the leucines. Variants of synthetic bradykinin containing one or two hydroxyproline moieties were prepared by using manual Edman degradation and/or enzymatic methods. The tandem mass spectra of these peptides were recorded. The C-terminal wn fragment ions allow the differentiation of 4-hydroxyproline from the 3-isomer and isoleucine, while the N-terminal an ions containing 4-hydroxyproline undergo H2O elimination to differentiate this amino acid from the 3-isomer and leucine. Lys-C digestion of a mussel adhesive protein produced a set of decapeptides varying in the degree of hydroxylation of proline and tyrosine. Heterogeneity with respect to 3-hydroxyproline and 4-hydroxyproline at a certain position in these peptides was assessed by tandem mass spectrometry based on the wn ion series in the CID spectra of these Lys-C peptides. Some N-terminal ions further allow for the differentiation of these two isomeric species.

  11. Adsorption of water vapor by poly(styrenesulfonic acid), sodium salt: isothermal and isobaric adsorption equilibria.

    PubMed

    Toribio, F; Bellat, J P; Nguyen, P H; Dupont, M

    2004-12-15

    Air conditioning and dehumidifying systems based on sorption on solids are of great interest, especially in humid climates, because they allow reduction of thermal loads and use of chlorofluorocarbons. Previous studies have shown that hydrophilic polymers such as sulfonic polymers can have very high performance in water adsorption from air. The aim of this study was to characterize the water vapor adsorption properties of fully sulfonated and monosulfonated poly(styrenesulfonic acid), sodium salt, and to elucidate the mechanism of adsorption on these materials. Adsorption isotherms have been determined by TGA between 298 and 317 K for pressures ranging from 0.1 to 45 hPa. They have type II of the IUPAC classification and a small hysteresis loop between adsorption and desorption processes was observed only for the monosulfonated sample. Water content is up to 80% weight at 80% relative humidity. Adsorption isotherms have been well fitted with the FHH model. Adsorption-desorption isobars have been determined by TGA under 37 hPa in the temperature range 298-373 K. They show that these polymers can be completely regenerated by heating at 313 K under humidified air. No degradation of the adsorption properties has been observed after several regenerations. Adsorption enthalpies and entropies have been deduced from the Clapeyron equation and from DSC measurements. A good agreement was found. A mechanism of adsorption is proposed considering two kinds of adsorbate: bounded water in electrostatic interaction with functional groups and free water resulting from condensation.

  12. A novel method for molecular dynamics simulation in the isothermal-isobaric ensemble

    NASA Astrophysics Data System (ADS)

    Huang, Cunkui; Li, Chunli; Choi, Phillip Y. K.; Nandakumar, K.; Kostiuk, Larry W.

    2011-01-01

    A novel algorithm is proposed to study fluid properties in the isothermal-isobaric (NPT) ensemble. The major feature of this approach is that the constant pressure in the NPT ensemble is created by two auto-adjusting boundaries that allow the system volume to fluctuate. Relative to other methods used to create the NPT ensemble, this approach is simpler to perform since no additional variables are introduced into the simulation system. To test this method, two systems with the same constant target pressure and temperature but different thermostats (Nose-Hoover and Berendsen) were performed by using a commonly used cut-off distance (i.e. r c = 2.5σ). The simulation results show that the proposed method works well in terms of creating spatially uniform mean temperature, pressure and density while still allowing appropriate levels of instantaneous fluctuations for observable quantities. The fluctuations of the system volume produced by this method were compared with that calculated by the theoretical equation. To test the reliability of the proposed method, additional simulations were carried out at eight different thermodynamic states but with the use of a longer cut-off distance (r c = 4.5σ). The results were compared with those obtained using the Nose-Hoover barostat with an r c of 4.5σ, as well as with experiments. The comparison shows that the results using the algorithm proposed in this article agree well with those obtained using other methods.

  13. Proteomic analysis of astrocytic secretion that regulates neurogenesis using quantitative amine-specific isobaric tagging

    SciTech Connect

    Yan, Hu; Zhou, Wenhao; Wei, Liming; Zhong, Fan; Yang, Yi

    2010-01-08

    Astrocytes are essential components of neurogenic niches that affect neurogenesis through membrane association and/or the release of soluble factors. To identify factors released from astrocytes that could regulate neural stem cell differentiation and proliferation, we used mild oxygen-glucose deprivation (OGD) to inhibit the secretory capacity of astrocytes. Using the Transwell co-culture system, we found that OGD-treated astrocytes could not promote neural stem cell differentiation and proliferation. Next, isobaric tagging for the relative and absolute quantitation (iTRAQ) proteomics techniques was performed to identify the proteins in the supernatants of astrocytes (with or without OGD). Through a multi-step analysis and gene ontology classification, 130 extracellular proteins were identified, most of which were involved in neuronal development, the inflammatory response, extracellular matrix composition and supportive functions. Of these proteins, 44 had never been reported to be produced by astrocytes. Using ProteinPilot software analysis, we found that 60 extracellular proteins were significantly altered (27 upregulated and 33 downregulated) in the supernatant of OGD-treated astrocytes. Among these proteins, 7 have been reported to be able to regulate neurogenesis, while others may have the potential to regulate neurogenesis. This study profiles the major proteins released by astrocytes, which play important roles in the modulation of neurogenesis.

  14. Optimized proteomic analysis of a mouse model of cerebellar dysfunction using amine-specific isobaric tags

    PubMed Central

    Hu, Jun; Qian, Jin; Borisov, Oleg; Pan, Sanqiang; Li, Yan; Liu, Tong; Deng, Longwen; Wannemacher, Kenneth; Kurnellas, Michael; Patterson, Christa; Elkabes, Stella; Li, Hong

    2008-01-01

    Recent proteomic applications have demonstrated their potential for revealing the molecular mechanisms underlying neurodegeneration. The present study quantifies cerebellar protein changes in mice that are deficient in plasma membrane calcium ATPase 2 (PMCA2), an essential neuronal pump that extrudes calcium from cells and is abundantly expressed in Purkinje neurons. PMCA2-null mice display motor dyscoordination and unsteady gait deficits observed in neurological diseases such as multiple sclerosis and ataxia. We optimized an amine-specific isobaric tags (iTRAQ™)-based shotgun proteomics workflow for this study. This workflow took consideration of analytical variance as a function of ion signal intensity and employed biological repeats to aid noise reduction. Even with stringent protein identification criteria, we could reliably quantify nearly 1000 proteins, including many neuronal proteins that are important for synaptic function. We identified 21 proteins that were differentially expressed in PMCA2-null mice. These proteins are involved in calcium homeostasis, cell structure and chromosome organization. Our findings shed light on the molecular changes that underlie the neurological deficits observed in PMCA2-null mice. The optimized workflow presented here will be valuable for others who plan to implement the iTRAQ method. PMID:16800037

  15. Revalidation of the Isobaric Multiplet Mass Equation for the A =20 quintet

    NASA Astrophysics Data System (ADS)

    Glassman, Brent; Perez-Loureiro, D.; Wrede, C.; Allen, J.; Bardyan, D.; Bennett, M.; Brown, A.; Chipps, K.; Febbraro, M.; Fry, Cathleen; Hall, O.; Hall, M.; Liddick, S.; O'Malley, P.; Ong, W.; Pain, S.; Schwartz, S.; Shidling, P.; Sims, H.; Thompson, P.; Zhang, E.

    2016-03-01

    An unexpected breakdown of the Isobaric Multiplet Mass Equation (IMME) for the A =20, T =2 quintet was recently reported based on a precise measurement of the 20Mg mass and adopted data on the other members. The adopted value for 20Na presented the greatest deviation from the IMME fit and was based on relatively imprecise beta delayed proton decay measurements. We used the superallowed 0+ to 0+ beta decay of 20Mg to feed the lowest T =2 state in 20Na, and the high purity germanium detector array SeGA to detect its gamma-ray de-excitation for the first time. Using the gamma-ray energies, we were able to precisely measure the excitation energy to be 6498.4 +/-0 .2stat+/-0.4syst keV. By incorporating this newly measured value we find that the IMME is revalidated. We gratefully acknowledge the NSCL staff for technical assistance and for providing the 20Mg beam. This work was supported by the National Science Foundation (USA) under Grants No. PHY-1102511, No. PHY-1419765, and No. PHY-1404442.

  16. Improved Isobaric Tandem Mass Tag Quantification by Ion Mobility-Mass Spectrometry

    PubMed Central

    Li, Lingjun

    2014-01-01

    Isobaric tandem mass tags are an attractive alternative to mass difference tags and label free approaches for quantitative proteomics due to the high degree of multiplexing that can be performed with their implementation. A drawback of tandem mass tags are that the co-isolation and co-fragmentation of labeled peptide precursors can result in chimeric MS/MS spectra that can underestimate the fold-change expression of each peptide. Two methods (QuantMode and MS3) have addressed this concern for ion trap and orbitrap instruments, but there is still a need to solve this problem for quadrupole time-of-flight (Q-TOF) instruments. Ion mobility (IM) separations coupled to Q-TOF instruments have the potential to mitigate MS/MS spectra chimeracy since IM-MS has the ability to separate ions based on charge, m/z, and collision cross section (CCS). This work presents results that showcase the power of IM-MS to improve tandem mass tag peptide quantitation accuracy by resolving co-isolated differently charged and same charged peptides prior to MS/MS fragmentation. PMID:24677527

  17. Precision Test of the Isobaric Multiplet Mass Equation in the A = 32, T = 2 Quintet

    NASA Astrophysics Data System (ADS)

    Ferrer, R.; Kwiatkowski, A. A.; Bollen, G.; Campbell, C. M.; Folden, C. M., III; Lincoln, D.; Morrissey, D. J.; Pang, G. K.; Prinke, A.; Savory, J.; Schwarz, S.

    2008-10-01

    Masses of the radionuclides ^32,33Si and ^34P and of the stable nuclide ^32S have been measured with the Low Energy Beam and Ion Trap (LEBIT) Penning trap mass spectrometer. Relative mass uncertainties of 3 x 10-8 and better have been achieved. The measured mass value of ^32Si differs from the literature value [1,2] by four standard deviations. The precise mass determination of ^32Si and ^32S have been employed to test the isobaric multiplet mass equation for the A = 32, T= 2 isospin quintet. The experimental results indicate a significant deviation from the quadratic form. This work has been supported by Michigan State University, the NSF under contract number PHY- 0606007, and the DOE under the contract DE-FG02-00ER41144. References: 1. G. Audi, A.H. Wapstra, and C. Thibault, Nucl. Phys. A729 (2003) 337 2. A. Paul, S. R"ottger, A. Zimbal, and U. Keyser, Hyperfine Interact. 132 (2001) 189

  18. Isobar channels and nucleon resonances in pi+ pi- electroproduction on protons

    SciTech Connect

    Fedotov, Gleb; Burkert, Volker; Golovach, Evgeny; Elouadrhiri, Latifa; Isupov, Evgeny; Ishkhanov, Boris; Mokeev, Viktor; Shvedunov, Nikolay

    2008-07-01

    http://dx.doi.org/10.1134/S1063778808070272
    A comprehensive set of differential cross sections for the reaction y v p--> pi - pi + p at the square of the photon 4-momentum in the range 0.2 < Q 2 < 0.6 GeV2 and the invariant mass of final-state hadrons in the range 1.3 < W < 1.6 GeV was first obtained with the CLAS detector at the Thomas Jefferson Laboratory. An analysis of these data on the basis of the phenomenological model developed by physicists from the Institute of Nuclear Physics at Moscow State University (INP MSU) and Thomas Jefferson Laboratory (INP MSU-Hall B at Jefferson Lab Collaboration) made it possible to determine, for the first time, the contributions of all isobar channels to the differential cross sections in question. The possibility of extracting the Q 2 dependences of the electromagnetic form factors for the P 11(1440) and D 13(1520) resonances in a kinematical region that is the most sensitive to the contribution of the meson-baryon cloud to the str

  19. Microscopic analysis of complete 90Zr(p,n) spectra including the Δ isobar effect

    NASA Astrophysics Data System (ADS)

    Osterfeld, F.; Cha, D.; Speth, J.

    1985-02-01

    A microscopic analysis of the complete forward angle spectra of the 90Zr(p,n) reaction is presented for an incident energy of 200 MeV. It is shown that the whole spectra up to an excitation energy of Ex=70 MeV are the result of correlated one-particle-one-hole (1p1h) spin-isospin transitions only. The spectra reflect, therefore, the linear spin-isospin response of the target nucleus to the probing (p,n) field. Two different cross section calculations are performed: one with usual random phase approximation wave functions and one with generalized random phase approximation wave functions which include Δ isobar degrees of freedom explicitly. We find that the theoretical cross sections calculated with random phase approximation wave functions, which provide the lower limit of spin-isospin strength, describe the data rather well at all scattering angles, while the random phase approximation +Δ cross sections underestimate the data at forward angles. In this connection we discuss the quenching of the spin-isospin strength in detail.

  20. An Improved Method for Determining Absolute Phosphorylation Stoichiometry Using Bayesian Statistics and Isobaric Labeling.

    PubMed

    Lim, Matthew Y; O'Brien, Jonathon; Paulo, Joao A; Gygi, Steven P

    2017-10-06

    Phosphorylation stoichiometry, or occupancy, is one element of phosphoproteomics that can add useful biological context(1). We previously developed a method to assess phosphorylation stoichiometry on a proteome-wide scale(2). The stoichiometry calculation relies on identifying and measuring the levels of each nonphosphorylated counterpart peptide with and without phosphatase treatment. The method, however, is problematic in that low stoichiometry phosphopeptides can return negative stoichiometry values if measurement error is larger than the percent stoichiometry. Here, we have improved the stoichiometry method through the use of isobaric labeling with 10-plex TMT reagents. In this way, 5 phosphatase treated and 5 untreated samples are compared simultaneously so that each stoichiometry is represented by 5 ratio measurements with no missing values. We applied the method to determine basal stoichiometries of HCT116 cells growing in culture. With this method, we analyzed 5 biological replicates simultaneously with no need for phosphopeptide enrichment. Additionally, we developed a Bayesian model to estimate phosphorylation stoichiometry as a parameter confined to an interval between 0 and 1 implemented as an R/Stan script. Consequently, both point and interval estimates are consistent with the plausible range of values for stoichiometry. Finally, we report absolute stoichiometry measurements with credible intervals for 6,772 phosphopeptides containing at least a single phosphorylation site.

  1. Volume crossover in deeply supercooled water adiabatically freezing under isobaric conditions.

    PubMed

    Aliotta, Francesco; Giaquinta, Paolo V; Pochylski, Mikolaj; Ponterio, Rosina C; Prestipino, Santi; Saija, Franz; Vasi, Cirino

    2013-05-14

    The irreversible return of a supercooled liquid to stable thermodynamic equilibrium often begins as a fast process which adiabatically drives the system to solid-liquid coexistence. Only at a later stage will solidification proceed with the expected exchange of thermal energy with the external bath. In this paper we discuss some aspects of the adiabatic freezing of metastable water at constant pressure. In particular, we investigated the thermal behavior of the isobaric gap between the molar volume of supercooled water and that of the warmer ice-water mixture which eventually forms at equilibrium. The available experimental data at ambient pressure, extrapolated into the metastable region within the scheme provided by the reference IAPWS-95 formulation, show that water ordinarily expands upon (partially) freezing under isenthalpic conditions. However, the same scheme also suggests that, for increasing undercoolings, the volume gap is gradually reduced and eventually vanishes at a temperature close to the currently estimated homogeneous ice nucleation temperature. This behavior is contrasted with that of substances which do not display a volumetric anomaly. The effect of increasing pressures on the alleged volume crossover from an expanded to a contracted ice-water mixture is also discussed.

  2. Differentiating Isobaric Steroid Hormone Metabolites Using Multi-Stage Tandem Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Tedmon, Lauren; Barnes, Jeremy S.; Nguyen, Hien P.; Schug, Kevin A.

    2013-03-01

    Steroid hormones and their metabolites are currently undergoing clinical trials as potential therapeutics for traumatic brain injury (TBI). To support this work, it is necessary to develop improved procedures for differentiating isobaric species in this compound class. Equilin sulfate (E-S), estrone sulfate (E1-S), 17α-dihydroequilin sulfate (ADHE-S), and 17β-dihydroequilin sulfate (BDHE-S) are primary constituents in hormone replacement therapies, such as Premarin, which are among pharmaceuticals being investigated for TBI treatment. The latter three compounds are isomers and can be difficult to differentiate in trace analytical determinations. In this work, a systematic study of the fragmentation of ADHE-S, BDHE-S, E1-S, and E-S under different stages of higher order tandem mass spectrometry (MSn) and variation of collision energy, allowed optimization of conditions for distinguishing the isomeric structures. For epimeric variants (e.g., ADHE-S versus BDHE-S; α- versus β-stereoisomerization in the C-17 position), differentiation was achieved at MS4 and fragmentation was demonstrated through MS5. Computational analysis was performed to further explore differences in the fragmentation pathways due to changes in stereochemistry.

  3. Cross isobar angles of surface winds - application for downscaling from synoptic data at the Israeli coast

    NASA Astrophysics Data System (ADS)

    Berkovic, Sigalit; Alpert, Pinhas

    2017-04-01

    Study of future East Mediterranean coastal surface winds may require downscaling from global models low tropospheric data, since surface winds are often under predicted. Synoptic classification may be of assistance in statistical downscaling. This work considers the relevance of higher level winds to predict the surface winds. The relations between surface and 850 hPa winds are explored according to the cross isobar angle (CIA) of 1000 and 850 hPa levels calculated from radiosonde data at Beit-Dagan (BD), a station at the Israeli coastal plain. Two extreme categories were found. Under the first category, low tropospheric strong thermal inversion prevents efficient interaction between these two levels and the CIA values are as high as ±180°. In the second category, as expected, downscaling of surface winds from 850 hPa is efficient under cyclone activity due to strong vertical mixing. In this category CIA values are ±50°. An inter-comparison of the CIAs between ERA-INTERIM and radiosonde data shows good agreement in both categories for reanalysis data. Thus suggesting some ability to use even model data but at flat coastal areas.

  4. Quantifying the Chiral Magnetic Effect in Isobaric Heavy Ion Collisions Using Hydrodynamic Simulations

    NASA Astrophysics Data System (ADS)

    Lilleskov, Elias; Liao, Jinfeng; Jiang, Yin; Shi, Shuzhe

    2016-09-01

    The quark-gluon plasma created in heavy ion collisions is an exotic state of matter in which many unusual phenomena are manifested. One such phenomenon is the ``Chiral-Magnetic Effect'' (CME), wherein the powerful magnetic fields generated by colliding ions spin-polarize chiral quarks, causing a net transport effect in the direction of the fields. The CME predicts specific charge-dependent correlation observables, for which experimental evidence was reported, although the evidence is subject to background contamination. Isobaric collision experiments have been planned for 2018 at RHIC, which will study this effect by comparing 96Ru-96Ru and 96Zr-96Zr collisions. The two colliding systems are expected to have nearly identical bulk properties (including background contamination), yet about 10% difference in their magnetic fields due to different nuclear charges. This provides a unique opportunity to disentangle the CME observable and background effects. By simulating this effect using anomalous hydrodynamic simulations, we make a quantitative prediction for the CME-induced signal for several centralities in each of these two colliding systems. Our results suggest a significant enough difference in the signal to be experimentally detected- on the order of 15-20%. Thanks to the Indiana University REU program for their support.

  5. Facilitation of gastric compliance and cardiovascular reaction by repeated isobaric distension of the rat stomach

    PubMed Central

    Römer, Markus; Painsipp, Evelin; Schwetz, Ines; Holzer, Peter

    2015-01-01

    Gastric distension causes cardiovascular reactions and enhances gastric compliance. Here we investigated how these responses are related to each other, whether they change upon repeated distension and which neural mechanisms are involved. Mean arterial blood pressure (MAP) in phenobarbital-anaesthetized rats was recorded from a carotid artery and gastric compliance determined with an electronic barostat. Runs of intermittent gastric distension were generated by stepwise increments (5 mm Hg) of intragastric pressure. While gastric compliance peaked at intragastric pressures of 20 mm Hg, the change in MAP (predominantly hypotension) was largest at intragastric pressures beyond 30 mm Hg. Repeated distension enhanced the MAP response to intragastric pressures beyond 35 mm Hg, whereas gastric compliance was facilitated primarily at intragastric pressures below 20 mm Hg. This facilitation of gastric compliance depended on the magnitude of the preceding distension. The MAP response to distension was enhanced by nitric oxide synthase inhibition, inhibited by subdiaphragmatic vagotomy but hardly affected by coeliac ganglionectomy. The facilitation of gastric compliance was changed by vagotomy in a complex manner but left unaltered by the other interventions. These findings show that isobaric gastric distension elicits both MAP and gastric compliance responses whose characteristics, mechanisms and sensitization properties differ profoundly. PMID:15916627

  6. Acute Aortic Dissection Biomarkers Identified Using Isobaric Tags for Relative and Absolute Quantitation

    PubMed Central

    Xiao, Ziya; Xue, Yuan; Gu, Guorong; Zhang, Yaping; Zhang, Jin; Fan, Fan; Luan, Xiao; Deng, Zhi; Tao, Zhengang; Song, Zhen-ju; Tong, Chaoyang; Wang, Haojun

    2016-01-01

    The purpose of this study was to evaluate the utility of potential serum biomarkers for acute aortic dissection (AAD) that were identified by isobaric Tags for Relative and Absolute Quantitation (iTRAQ) approaches. Serum samples from 20 AAD patients and 20 healthy volunteers were analyzed using iTRAQ technology. Protein validation was performed using samples from 120 patients with chest pain. A total of 355 proteins were identified with the iTRAQ approach; 164 proteins reached the strict quantitative standard, and 125 proteins were increased or decreased more than 1.2-fold (64 and 61 proteins were up- and downregulated, resp.). Lumican, C-reactive protein (CRP), thrombospondin-1 (TSP-1), and D-dimer were selected as candidate biomarkers for the validation tests. Receiver operating characteristic (ROC) curves show that Lumican and D-dimer have diagnostic value (area under the curves [AUCs] 0.895 and 0.891, P < 0.05). For Lumican, the diagnostic sensitivity and specificity were 73.33% and 98.33%, while the corresponding values for D-dimer were 93.33% and 68.33%. For Lumican and D-dimer AAD combined diagnosis, the sensitivity and specificity were 88.33% and 95%, respectively. In conclusion, Lumican has good specificity and D-dimer has good sensitivity for the diagnosis of AAD, while the combined detection of D-dimer and Lumican has better diagnostic value. PMID:27403433

  7. A Triple Knockout (TKO) Proteomics Standard for Diagnosing Ion Interference in Isobaric Labeling Experiments

    NASA Astrophysics Data System (ADS)

    Paulo, Joao A.; O'Connell, Jeremy D.; Gygi, Steven P.

    2016-10-01

    Isobaric labeling is a powerful strategy for quantitative mass spectrometry-based proteomic investigations. A complication of such analyses has been the co-isolation of multiple analytes of similar mass-to-charge resulting in the distortion of relative protein abundance measurements across samples. When properly implemented, synchronous precursor selection and triple-stage mass spectrometry (SPS-MS3) can reduce the occurrence of this phenomenon, referred to as ion interference. However, no diagnostic tool is available currently to rapidly and accurately assess ion interference. To address this need, we developed a multiplexed tandem mass tag (TMT)-based standard, termed the triple knockout (TKO). This standard is comprised of three yeast proteomes in triplicate, each from a strain deficient in a highly abundant protein (Met6, Pfk2, or Ura2). The relative abundance patterns of these proteins, which can be inferred from dozens of peptide measurements can demonstrate ion interference in peptide quantification. We expect no signal in channels where the protein is knocked out, permitting maximum sensitivity for measurements of ion interference against a null background. Here, we emphasize the need to investigate further ion interference-generated ratio distortion and promote the TKO standard as a tool to investigate such issues.

  8. Neutron-skin thickness from the study of the anti-analog giant dipole resonance

    SciTech Connect

    Krasznahorkay, A.; Stuhl, L.; Csatlos, M.; Algora, A.; and others

    2012-10-20

    The {gamma}-decay of the anti-analog of the giant dipole resonance (AGDR) to the isobaric analog state has been measured following the p({sup 124}Sn,n) reaction at a beam energy of 600 MeV/nucleon. The energy of the transition was also calculated with state-of-the-art self-consistent relativistic random-phase approximation (RPA) and turned out to be very sensitive to the neutronskin thickness ({Delta}R{sub pn}). By comparing the theoretical results with the measured one, the {Delta}R{sub pn} value for {sup 124}Sn was deduced to be 0.21 {+-} 0.07 fm, which agrees well with the previous results. The present method offers new possibilities for measuring the neutron-skin thicknesses of very exotic isotopes.

  9. Large-Scale and Deep Quantitative Proteome Profiling Using Isobaric Labeling Coupled with Two-Dimensional LC-MS/MS.

    PubMed

    Gritsenko, Marina A; Xu, Zhe; Liu, Tao; Smith, Richard D

    2016-01-01

    Comprehensive, quantitative information on abundances of proteins and their posttranslational modifications (PTMs) can potentially provide novel biological insights into diseases pathogenesis and therapeutic intervention. Herein, we introduce a quantitative strategy utilizing isobaric stable isotope-labeling techniques combined with two-dimensional liquid chromatography-tandem mass spectrometry (2D-LC-MS/MS) for large-scale, deep quantitative proteome profiling of biological samples or clinical specimens such as tumor tissues. The workflow includes isobaric labeling of tryptic peptides for multiplexed and accurate quantitative analysis, basic reversed-phase LC fractionation and concatenation for reduced sample complexity, and nano-LC coupled to high resolution and high mass accuracy MS analysis for high confidence identification and quantification of proteins. This proteomic analysis strategy has been successfully applied for in-depth quantitative proteomic analysis of tumor samples and can also be used for integrated proteome and PTM characterization, as well as comprehensive quantitative proteomic analysis across samples from large clinical cohorts.

  10. Analogy, explanation, and proof

    PubMed Central

    Hummel, John E.; Licato, John; Bringsjord, Selmer

    2014-01-01

    People are habitual explanation generators. At its most mundane, our propensity to explain allows us to infer that we should not drink milk that smells sour; at the other extreme, it allows us to establish facts (e.g., theorems in mathematical logic) whose truth was not even known prior to the existence of the explanation (proof). What do the cognitive operations underlying the inference that the milk is sour have in common with the proof that, say, the square root of two is irrational? Our ability to generate explanations bears striking similarities to our ability to make analogies. Both reflect a capacity to generate inferences and generalizations that go beyond the featural similarities between a novel problem and familiar problems in terms of which the novel problem may be understood. However, a notable difference between analogy-making and explanation-generation is that the former is a process in which a single source situation is used to reason about a single target, whereas the latter often requires the reasoner to integrate multiple sources of knowledge. This seemingly small difference poses a challenge to the task of marshaling our understanding of analogical reasoning to understanding explanation. We describe a model of explanation, derived from a model of analogy, adapted to permit systematic violations of this one-to-one mapping constraint. Simulation results demonstrate that the resulting model can generate explanations for novel explananda and that, like the explanations generated by human reasoners, these explanations vary in their coherence. PMID:25414655

  11. Are Scientific Analogies Metaphors?

    DTIC Science & Technology

    1981-02-01

    psychospiritual processes. A more modern example of unclarified analogy is Freud’s (1973; reprinted from 1955) discussion of anal- eroticism , in which...299-304. Freud, S. On transformations of instinct as exemplified in anal eroticism . In J. Strachey (Ed.), The standard 37 edition of the complete

  12. Quantum Analog Computing

    NASA Technical Reports Server (NTRS)

    Zak, M.

    1998-01-01

    Quantum analog computing is based upon similarity between mathematical formalism of quantum mechanics and phenomena to be computed. It exploits a dynamical convergence of several competing phenomena to an attractor which can represent an externum of a function, an image, a solution to a system of ODE, or a stochastic process.

  13. Quantum Analog Computing

    NASA Technical Reports Server (NTRS)

    Zak, M.

    1998-01-01

    Quantum analog computing is based upon similarity between mathematical formalism of quantum mechanics and phenomena to be computed. It exploits a dynamical convergence of several competing phenomena to an attractor which can represent an externum of a function, an image, a solution to a system of ODE, or a stochastic process.

  14. An Interesting Analogy

    ERIC Educational Resources Information Center

    Pacheco, Jose M.; Fernandez, Isabel

    2002-01-01

    The aim of this note is to give some insight into the formal unity of a very applicable area of mathematics by showing an interesting analogy between the weak part of the Rouche-Frobenius theorem and the existence result for the initial value problem for the general first-order linear two-dimensional PDE.

  15. Analogy, explanation, and proof.

    PubMed

    Hummel, John E; Licato, John; Bringsjord, Selmer

    2014-01-01

    People are habitual explanation generators. At its most mundane, our propensity to explain allows us to infer that we should not drink milk that smells sour; at the other extreme, it allows us to establish facts (e.g., theorems in mathematical logic) whose truth was not even known prior to the existence of the explanation (proof). What do the cognitive operations underlying the inference that the milk is sour have in common with the proof that, say, the square root of two is irrational? Our ability to generate explanations bears striking similarities to our ability to make analogies. Both reflect a capacity to generate inferences and generalizations that go beyond the featural similarities between a novel problem and familiar problems in terms of which the novel problem may be understood. However, a notable difference between analogy-making and explanation-generation is that the former is a process in which a single source situation is used to reason about a single target, whereas the latter often requires the reasoner to integrate multiple sources of knowledge. This seemingly small difference poses a challenge to the task of marshaling our understanding of analogical reasoning to understanding explanation. We describe a model of explanation, derived from a model of analogy, adapted to permit systematic violations of this one-to-one mapping constraint. Simulation results demonstrate that the resulting model can generate explanations for novel explananda and that, like the explanations generated by human reasoners, these explanations vary in their coherence.

  16. Reasoning through Instructional Analogies

    ERIC Educational Resources Information Center

    Kapon, Shulamit; diSessa, Andrea A.

    2012-01-01

    This article aims to account for students' assessments of the plausibility and applicability of analogical explanations, and individual differences in these assessments, by analyzing properties of students' underlying knowledge systems. We developed a model of explanation and change in explanation focusing on knowledge elements that provide a…

  17. Arterial Pressure Analog.

    ERIC Educational Resources Information Center

    Heusner, A. A.; Tracy, M. L.

    1980-01-01

    Describes a simple hydraulic analog which allows students to explore some physical aspects of the cardiovascular system and provides them with a means to visualize and conceptualize these basic principles. Simulates the behavior of arterial pressure in response to changes in heart rate, stroke volume, arterial compliance, and peripheral…

  18. How Analogy Drives Physics

    SciTech Connect

    Hofstadter, Doug

    2004-05-05

    Many new ideas in theoretical physics come from analogies to older ideas in physics. For instance, the abstract notion of 'isospin' (or isotopic spin) originated in the prior concept of 'spin' (quantized angular momentum); likewise, the concept of 'phonon' (quantum of sound, or quantized collective excitation of a crystal) was based on the prior concept of 'photon' (quantum of light, or quantized element of the electromagnetic field). But these two examples, far from being exceptions, in fact represent the bread and butter of inventive thinking in physics. In a nutshell, intraphysics analogy-making -- borrowing by analogy with something already known in another area of physics -- is central to the progress of physics. The aim of this talk is to reveal the pervasiveness -- indeed, the indispensability -- of this kind of semi-irrational, wholly intuitive type of thinking (as opposed to more deductive mathematical inference) in the mental activity known as 'doing physics'. Speculations as to why wild analogical leaps are so crucial to the act of discovery in physics (as opposed to other disciplines) will be offered.

  19. Terrestrial analogs to Mars

    NASA Technical Reports Server (NTRS)

    Farr, T. G.; Arcone, S.; Arvidson, R.; Baker, V.; Barlow, N.; Beaty, D.; Bell, M.; Blankenship, D.; Bridges, N.; Briggs, G.; hide

    2002-01-01

    It is well recognized that interpretations of Mars must begin with the Earth as a reference. The most successful comparisons have focused on understanding geologic processes on the Earth well enough to extrapolate to Mars' environment. Several facets of terrestrial analog studies have been pursued and are continuing.

  20. Isobar-hole and two-particle-two-hole effects in the spin response of 90Zr and 208Pb

    NASA Astrophysics Data System (ADS)

    Cha, D.; Schwesinger, B.; Wambach, J.; Speth, J.

    1984-11-01

    We give a microscopic description of low-energy unnatural-parity excitations in 90Zr and 208Pb in a restricted Hilbert space spanned by one-particle-one-hole, two-particle-two-hole as well as one-isobar-one-hole excitations. In this model space it seems possible to reduce the effective two-body interaction to correlated one-pion and one-rho-meson exchange and yet get a good description of measured strength functions.

  1. Gas-phase ion-molecule reactions for resolution of atomic isobars: AMS and ICP-MS perspectives

    NASA Astrophysics Data System (ADS)

    Bandura, Dmitry R.; Baranov, Vladimir I.; Litherland, A. E.; Tanner, Scott D.

    2006-09-01

    Ion-molecule reactions that can be used for resolution of spectral overlaps of long-lived or stable (T1/2 > 100 years) atomic isobars on the long-lived radio-isotopes (100 < T1/2 < 1012 years) in mass spectrometry are considered. Results for the separations of isobaric overlaps via cation reactions with NO, N2O, O2, CO2, C2H2, CH3F studied with the Inductively Coupled Plasma Dynamic Reaction Cell(TM) Mass Spectrometer (ICP-DRC(TM)-MS) with use of stable isotopes are presented. Overview of potential and reported reactions for separation of 35 isobars is given. Potential for the following isobaric pairs separation is shown (reaction gas and the extent of separation achieved to date in parenthesis): 32Si+/32S+(NO, 5 x 104), 40K+/40Ar+(N2O, 1.9 x 103), 40K+/40Ca+(N2O, 50), 59Ni+/59Co+(N2O, 6), 79Se+/79Br+(O2, 7.2 x 103), 81Kr+/81Br+(C2H2, 1.5 x 104), 93Mo+/93Nb+(N2O, 100), 93Mo+/93Zr+(N2O, 150), 135Cs+/135Ba+(N2O, 8 x 104), 137,138La+/137,138Ba+(O2, 40), 146Sm+/146Nd+(CO2, 1.5 x 105), 176Lu+/176Hf+(NO, 2.8 x 103), 187Re+/187Os+(N2O, 2.8 x 104). Effect of instrumental parameters on reactivity is discussed. The relevance of this work to accelerator mass spectrometry is discussed briefly.

  2. Isobaric yield ratios in heavy-ion reactions, and symmetry energy of neutron-rich nuclei at intermediate energies

    SciTech Connect

    Ma Chunwang; Wang Fang; Ma Yugang; Jin Chan

    2011-06-15

    The isobaric yield ratios of the fragments produced in the neutron-rich {sup 48}Ca and {sup 64}Ni projectile fragmentation are analyzed in the framework of a modified Fisher model. The correlations between the isobaric yield ratios (R) and the energy coefficients in the Weiszaecker-Beth semiclassical mass formula (the symmetry-energy term a{sub sym}, the Coulomb-energy term a{sub c}, and the pairing-energy term a{sub p}) and the difference between the chemical potentials of the neutron and proton ({mu}{sub n}-{mu}{sub p}) are investigated. Simple correlations between ({mu}{sub n}-{mu}{sub p})/T, a{sub c}/T, a{sub sym}/T, and a{sub p}/T (where T is the temperature), and lnR are obtained. It is suggested that ({mu}{sub n}-{mu}{sub p})/T, a{sub c}/T, a{sub sym}/T, and a{sub p}/T of neutron-rich nuclei can be extracted using isobaric yield ratios for heavy-ion collisions at intermediate energies.

  3. Influence of multiple scattering and absorption on the full scattering profile and the isobaric point in tissue.

    PubMed

    Duadi, Hamootal; Fixler, Dror

    2015-05-01

    Light reflectance and transmission from soft tissue has been utilized in noninvasive clinical measurement devices such as the photoplethysmograph (PPG) and reflectance pulse oximeter. Incident light on the skin travels into the underlying layers and is in part reflected back to the surface, in part transferred and in part absorbed. Most methods of near infrared (NIR) spectroscopy focus on the volume reflectance from a semi-infinite sample, while very few measure transmission. We have previously shown that examining the full scattering profile (angular distribution of exiting photons) provides more comprehensive information when measuring from a cylindrical tissue. Furthermore, an isobaric point was found which is not dependent on changes in the reduced scattering coefficient. The angle corresponding to this isobaric point depends on the tissue diameter. We investigated the role of multiple scattering and absorption on the full scattering profile of a cylindrical tissue. First, we define the range in which multiple scattering occurs for different tissue diameters. Next, we examine the role of the absorption coefficient in the attenuation of the full scattering profile. We demonstrate that the absorption linearly influences the intensity at each angle of the full scattering profile and, more importantly, the absorption does not change the position of the isobaric point. The findings of this work demonstrate a realistic model for optical tissue measurements such as NIR spectroscopy, PPG, and pulse oximetery.

  4. Isobar Separation in a Multiple-Reflection Time-of-Flight Mass Spectrometer by Mass-Selective Re-Trapping

    NASA Astrophysics Data System (ADS)

    Dickel, Timo; Plaß, Wolfgang R.; Lippert, Wayne; Lang, Johannes; Yavor, Mikhail I.; Geissel, Hans; Scheidenberger, Christoph

    2017-03-01

    A novel method for (ultra-)high-resolution spatial mass separation in time-of-flight mass spectrometers is presented. Ions are injected into a time-of-flight analyzer from a radio frequency (rf) trap, dispersed in time-of-flight according to their mass-to-charge ratios and then re-trapped dynamically in the same rf trap. This re-trapping technique is highly mass-selective and after sufficiently long flight times can provide even isobaric separation. A theoretical treatment of the method is presented and the conditions for optimum performance of the method are derived. The method has been implemented in a multiple-reflection time-of-flight mass spectrometer and mass separation powers (FWHM) in excess of 70,000, and re-trapping efficiencies of up to 35% have been obtained for the protonated molecular ion of caffeine. The isobars glutamine and lysine (relative mass difference of 1/4000) have been separated after a flight time of 0.2 ms only. Higher mass separation powers can be achieved using longer flight times. The method will have important applications, including isobar separation in nuclear physics and (ultra-)high-resolution precursor ion selection in multiple-stage tandem mass spectrometry.

  5. Isobar Separation in a Multiple-Reflection Time-of-Flight Mass Spectrometer by Mass-Selective Re-Trapping

    NASA Astrophysics Data System (ADS)

    Dickel, Timo; Plaß, Wolfgang R.; Lippert, Wayne; Lang, Johannes; Yavor, Mikhail I.; Geissel, Hans; Scheidenberger, Christoph

    2017-06-01

    A novel method for (ultra-)high-resolution spatial mass separation in time-of-flight mass spectrometers is presented. Ions are injected into a time-of-flight analyzer from a radio frequency (rf) trap, dispersed in time-of-flight according to their mass-to-charge ratios and then re-trapped dynamically in the same rf trap. This re-trapping technique is highly mass-selective and after sufficiently long flight times can provide even isobaric separation. A theoretical treatment of the method is presented and the conditions for optimum performance of the method are derived. The method has been implemented in a multiple-reflection time-of-flight mass spectrometer and mass separation powers (FWHM) in excess of 70,000, and re-trapping efficiencies of up to 35% have been obtained for the protonated molecular ion of caffeine. The isobars glutamine and lysine (relative mass difference of 1/4000) have been separated after a flight time of 0.2 ms only. Higher mass separation powers can be achieved using longer flight times. The method will have important applications, including isobar separation in nuclear physics and (ultra-)high-resolution precursor ion selection in multiple-stage tandem mass spectrometry. [Figure not available: see fulltext.

  6. Isobar Separation in a Multiple-Reflection Time-of-Flight Mass Spectrometer by Mass-Selective Re-Trapping.

    PubMed

    Dickel, Timo; Plaß, Wolfgang R; Lippert, Wayne; Lang, Johannes; Yavor, Mikhail I; Geissel, Hans; Scheidenberger, Christoph

    2017-03-15

    A novel method for (ultra-)high-resolution spatial mass separation in time-of-flight mass spectrometers is presented. Ions are injected into a time-of-flight analyzer from a radio frequency (rf) trap, dispersed in time-of-flight according to their mass-to-charge ratios and then re-trapped dynamically in the same rf trap. This re-trapping technique is highly mass-selective and after sufficiently long flight times can provide even isobaric separation. A theoretical treatment of the method is presented and the conditions for optimum performance of the method are derived. The method has been implemented in a multiple-reflection time-of-flight mass spectrometer and mass separation powers (FWHM) in excess of 70,000, and re-trapping efficiencies of up to 35% have been obtained for the protonated molecular ion of caffeine. The isobars glutamine and lysine (relative mass difference of 1/4000) have been separated after a flight time of 0.2 ms only. Higher mass separation powers can be achieved using longer flight times. The method will have important applications, including isobar separation in nuclear physics and (ultra-)high-resolution precursor ion selection in multiple-stage tandem mass spectrometry. Graphical Abstract ᅟ.

  7. Quantification of Cell-Penetrating Peptide Associated with Polymeric Nanoparticles Using Isobaric-Tagging and MALDI-TOF MS/MS

    NASA Astrophysics Data System (ADS)

    Chiu, Jasper Z. S.; Tucker, Ian G.; McDowell, Arlene

    2016-11-01

    High sensitivity quantification of the putative cell-penetrating peptide di-arginine-histidine (RRH) associated with poly (ethyl-cyanoacrylate) (PECA) nanoparticles was achieved without analyte separation, using a novel application of isobaric-tagging and high matrix-assisted laser desorption/ionization coupled to time-of-flight (MALDI-TOF) mass spectrometry. Isobaric-tagging reaction equilibrium was reached after 5 min, with 90% or greater RRH peptide successfully isobaric-tagged after 60 min. The accuracy was greater than 90%, which indicates good reliability of using isobaric-tagged RRH as an internal standard for RRH quantification. The sample intra- and inter-spot coefficients of variations were less than 11%, which indicate good repeatability. The majority of RRH peptides in the nanoparticle formulation were physically associated with the nanoparticles (46.6%), whereas only a small fraction remained unassociated (13.7%). The unrecovered RRH peptide (~40%) was assumed to be covalently associated with PECA nanoparticles.

  8. O-H...O versus O-H...S hydrogen bonding. 3. IR-UV double resonance study of hydrogen bonded complexes of p-cresol with diethyl ether and its sulfur analog.

    PubMed

    Biswal, Himansu S; Wategaonkar, Sanjay

    2010-05-20

    In this work the hydrogen bonded complexes of diethyl ether (DEE) and diethyl sulfide (DES) with p-cresol (p-CR) were investigated. Only one conformer of the p-CR.DEE complex and three conformers of the p-CR.DES complex were found to be present under the supersonic jet expansion conditions. The conformational assignments were done with the help of IR-UV double resonance studies and ab initio calculations. The red shifts in the OH stretching frequency for the O-H...O and O-H...S hydrogen bonded complexes were quite close to each other. In fact, one of the p-CR.DES conformers showed a slightly larger red shift in the OH stretch than that in the p-CR.DEE conformer, which suggests that in this case sulfur is not a weak hydrogen bond acceptor as noted previously in case of the p-CR.H(2)O and p-CR.H(2)S complexes (Biswal et al. J. Phys. Chem. A 2009, 113, 5633). The natural bond orbital analysis also shows that the extent of overlap between sulfur lone pair orbitals (LP) and OH antibonding orbital (sigma*(OH)) was comparable to the oxygen (LP) and sigma*(OH) overlap, consistent with the similar magnitudes of the red shifts of OH stretch in the DES and DEE complexes. The computed binding energy of the p-CR.DES complex, however, was about 80% of the p-CR.DEE complex. The electron densities at the bond critical points indicated that the O-H...S interaction was weaker than the O-H...O interaction in this particular system also. The important finding of this study was that the IR red shifts in the H-bond donor X-H stretching frequency were not quite consistent with the computed binding energies and the atoms-in-molecules analysis contrary to the general understanding. Energy decomposition analysis suggests that O-H...S hydrogen bonding interaction is dispersive in nature and the dispersion contribution decreases with the increase in the length of the alkyl chain of the "S" hydrogen bond acceptor.

  9. MRI analysis of the ISOBAR TTL internal fixation system for the dynamic fixation of intervertebral discs: a comparison with rigid internal fixation

    PubMed Central

    2014-01-01

    Objectives Using magnetic resonance imaging (MRI), we analyzed the efficacy of the posterior approach lumbar ISOBAR TTL internal fixation system for the dynamic fixation of intervertebral discs, with particular emphasis on its effects on degenerative intervertebral disc disease. Methods We retrospectively compared the MRIs of 54 patients who had previously undergone either rigid internal fixation of the lumbar spine or ISOBAR TTL dynamic fixation for the treatment of lumbar spondylolisthesis. All patients had received preoperative and 6-, 12-, and 24-month postoperative MRI scans of the lumbar spine with acquisition of both routine and diffusion-weighted images (DWI). The upper-segment discs of the fusion were subjected to Pfirrmann grading, and the lumbar intervertebral discs in the DWI sagittal plane were manually drawn; the apparent diffusion coefficient (ADC) value was measured. Results ADC values in the ISOBAR TTL dynamic fixation group measured at the 6-, 12-, and 24-month postoperative MRI studies were increased compared to the preoperative ADC values. The ADC values in the ISOBAR TTL dynamic fixation group at 24 months postoperatively were significantly different from the preoperative values (P < 0.05). At 24 months, the postoperative ADC values were significantly different between the rigid fixation group and the ISOBAR TTL dynamic fixation group (P < 0.05). Conclusion MRI imaging findings indicated that the posterior approach lumbar ISOBAR TTL internal fixation system can prevent or delay the degeneration of intervertebral discs. PMID:24898377

  10. New analogs of trimethoprim.

    PubMed

    Then, R L; Böhni, E; Angehrn, P; Plozza-Nottebrock, H; Stoeckel, K

    1982-01-01

    Possible goals and recent developments in the field of antimicrobial 2,4-diamino-5-benzylpyrimidines are discussed. Three analogs of trimethoprim--all bearing different substituents at position 4 of the benzyl moiety and one also having the methoxy groups replaced by ethoxy substituents--are characterized in some detail. These analogs exhibit physicochemical properties different from those of trimethoprim and are potent inhibitors of several dihydrofolate reductases. Because they differ from trimethoprim in lipophilicity, their in vitro activity, spectrum of activity, and pharmacokinetic properties also differ from those of trimethoprim. These differences are judged to be the reason for enhanced in vivo efficacy against several experimental infections. Distinct pharmacokinetic differences observed in dogs include a longer elimination half-life and a larger volume of distribution. These favorable properties indicate the potential value of further studies in humans.

  11. Terrestrial Spaceflight Analogs: Antarctica

    NASA Technical Reports Server (NTRS)

    Crucian, Brian

    2013-01-01

    Alterations in immune cell distribution and function, circadian misalignment, stress and latent viral reactivation appear to persist during Antarctic winterover at Concordia Station. Some of these changes are similar to those observed in Astronauts, either during or immediately following spaceflight. Others are unique to the Concordia analog. Based on some initial immune data and environmental conditions, Concordia winterover may be an appropriate analog for some flight-associated immune system changes and mission stress effects. An ongoing smaller control study at Neumayer III will address the influence of the hypoxic variable. Changes were observed in the peripheral blood leukocyte distribution consistent with immune mobilization, and similar to those observed during spaceflight. Alterations in cytokine production profiles were observed during winterover that are distinct from those observed during spaceflight, but potentially consistent with those observed during persistent hypobaric hypoxia. The reactivation of latent herpesviruses was observed during overwinter/isolation, that is consistently associated with dysregulation in immune function.

  12. Analogy Construction versus Analogy Solution, and Their Influence on Transfer

    ERIC Educational Resources Information Center

    Harpaz-Itay, Yifat; Kaniel, Shlomo; Ben-Amram, Einat

    2006-01-01

    This study compares transfer performed by subjects trained to solve verbal analogies, with transfer by subjects trained to construct them. The first group (n = 57) received instruction in a strategy to solve verbal analogies and the second group (n = 66) was trained in strategies for constructing such analogies. Before and after intervention, all…

  13. Analogy Construction versus Analogy Solution, and Their Influence on Transfer

    ERIC Educational Resources Information Center

    Harpaz-Itay, Yifat; Kaniel, Shlomo; Ben-Amram, Einat

    2006-01-01

    This study compares transfer performed by subjects trained to solve verbal analogies, with transfer by subjects trained to construct them. The first group (n = 57) received instruction in a strategy to solve verbal analogies and the second group (n = 66) was trained in strategies for constructing such analogies. Before and after intervention, all…

  14. VIIP Bedrest Analog Roadmap

    NASA Technical Reports Server (NTRS)

    Villarreal, Jennifer D.

    2014-01-01

    The objective is to define successive bed rest campaigns leading to a potential VIIP (Vision Impairment and Intracranial Pressure) countermeasure. To determine if the analog is successful, changes need to occur in the following outcome measures (dependent variables): Intracranial pressure; Retinal nerve fiber layer; Choroidal engorgement; Globe flattening; Axial biometry; Optic nerve sheath diameter distention; Cycloplegic refraction; Visual acuity. Study parameters (independent variables) to include: CO2; Sodium; Exercise (resistive & aerobic); Strict tilt angle.

  15. Analog storage integrated circuit

    DOEpatents

    Walker, J. T.; Larsen, R. S.; Shapiro, S. L.

    1989-01-01

    A high speed data storage array is defined utilizing a unique cell design for high speed sampling of a rapidly changing signal. Each cell of the array includes two input gates between the signal input and a storage capacitor. The gates are controlled by a high speed row clock and low speed column clock so that the instantaneous analog value of the signal is only sampled and stored by each cell on coincidence of the two clocks.

  16. Antarctic analogs for Enceladus

    NASA Astrophysics Data System (ADS)

    Murray, A. E.; Andersen, D. T.; McKay, C. P.

    2014-12-01

    Enceladus is a new world for Astrobiology. The Cassini discovery of the icy plume emanating from the South Polar region indicates an active world, where detection of water, organics, sodium, and nano-particle silica in the plume strongly suggests that the source is a subsurface salty ocean reservoir. Recent gravity data from Cassini confirms the presence of a regional sea extending north to 50°S. An ocean habitat under a thick ice cover is perhaps a recurring theme in the Outer Solar System, but what makes Enceladus unique is that the plume jetting out into space is carrying samples of this ocean. Therefore, through the study of Enceladus' plumes we can gain new insights not only of a possible habitable world in the Solar Systems, but also about the formation and evolution of other icy-satellites. Cassini has been able to fly through this plume - effectively sampling the ocean. It is time to plan for future missions that do more detailed analyses, possibly return samples back to Earth and search for evidence of life. To help prepare for such missions, the need for earth-based analog environments is essential for logistical, methodological (life detection) and theoretical development. We have undertaken studies of two terrestrial environments that are close analogs to Enceladus' ocean: Lake Vida and Lake Untersee - two ice-sealed Antarctic lakes that represent physical, chemical and possibly biological analogs for Enceladus. By studying the diverse biology and physical and chemical constraints to life in these two unique lakes we will begin to understand the potential habitability of Enceladus and other icy moons, including possible sources of nutrients and energy, which together with liquid water are the key ingredients for life. Analog research such as this will also enable us to develop and test new strategies to search for evidence of life on Enceladus.

  17. Analog storage integrated circuit

    DOEpatents

    Walker, J.T.; Larsen, R.S.; Shapiro, S.L.

    1989-03-07

    A high speed data storage array is defined utilizing a unique cell design for high speed sampling of a rapidly changing signal. Each cell of the array includes two input gates between the signal input and a storage capacitor. The gates are controlled by a high speed row clock and low speed column clock so that the instantaneous analog value of the signal is only sampled and stored by each cell on coincidence of the two clocks. 6 figs.

  18. Light-front representation of chiral dynamics with Δ isobar and large-Nc relations

    DOE PAGES

    Granados, C.; Weiss, C.

    2016-06-13

    Transverse densities describe the spatial distribution of electromagnetic current in the nucleon at fixed light-front time. At peripheral distances b = O(Mπ–1) the densities are governed by chiral dynamics and can be calculated model-independently using chiral effective field theory (EFT). Recent work has shown that the EFT results can be represented in first-quantized form, as overlap integrals of chiral light-front wave functions describing the transition of the nucleon to soft-pion-nucleon intermediate states, resulting in a quantum-mechanical picture of the peripheral transverse densities. We now extend this representation to include intermediate states with Δ isobars and implement relations based on themore » large-Nc limit of QCD. We derive the wave function overlap formulas for the Δ contributions to the peripheral transverse densities by way of a three-dimensional reduction of relativistic chiral EFT expressions. Our procedure effectively maintains rotational invariance and avoids the ambiguities with higher-spin particles in the light-front time-ordered approach. We study the interplay of πN and πΔ intermediate states in the quantum-mechanical picture of the densities in a transversely polarized nucleon. We show that the correct Nc-scaling of the charge and magnetization densities emerges as the result of the particular combination of currents generated by intermediate states with degenerate N and Δ. The off-shell behavior of the chiral EFT is summarized in contact terms and can be studied easily. As a result, the methods developed here can be applied to other peripheral densities and to moments of the nucleon's generalized parton distributions.« less

  19. Amplitude, isobar and grey-scale imaging of ultrasonic shadows behind rigid, elastic and gaseous spheres.

    PubMed

    Filipczyński, L; Kujawska, T; Tymkiewicz, R; Wójcik, J

    1996-01-01

    The theory of wave reflection from spherical obstacles was applied for determination of the cause of the shadow created by plane wave pulses incident on rigid, steel, gaseous spheres and on spheres made of kidney stones. The spheres were immersed in water which was assumed to be a tissue-like medium. Acoustic pressure distributions behind the spheres with the radii of 1 mm, 2.5 mm and 3.5 mm were determined at the frequency of 5 MHz. The use of the exact wave theory enabled us to take into account the diffraction effects. The computed pressure distributions were verified experimentally at the frequency of 5 MHz for a steel sphere with a 2.5-mm radius. The experimental and theoretical pulses were composed of about three ultrasonic frequency periods. Acoustic pressure distributions in the shadow zone of all spheres were shown in the amplitude axonometric projection, in the grey scale and also as acoustic isobar patterns. Our analysis confirmed existing simpler descriptions of the shadow from the point of view of reflection and refraction effects; however, our approach is more general, also including diffraction effects and assuming the pulse mode. The analysis has shown that gaseous spherical inclusions caused shadows with very high dynamics of acoustic pressures that were about 15 dB higher in relation to all the other spheres. The shadow length, determined as the length at which one observes a 6-dB drop of the acoustic pressure, followed the relation r-6dB = 3.7a2/lambda with the accuracy of about 20% independent of the sphere type. lambda denotes the wavelength and a the sphere radius. Thus, a theoretical possibility of differentiating between gaseous and other inclusions and of estimation of the inclusion size in the millimeter range from the shadow was shown. The influence of the frequency-dependent attenuation on the shadow will be considered in the next study.

  20. Reaction chemistry and collisional processes in multiple devices for resolving isobaric interferences in ICP-MS.

    PubMed

    Bandura, D R; Baranov, V I; Tanner, S D

    2001-07-01

    A low-level review of the fundamentals of ion-molecule interactions is presented. These interactions are used to predict the efficiencies of collisional fragmentation, energy damping and reaction for a variety of neutral gases as a function of pressure in a rf-driven collision/reaction cell. It is shown that the number of collisions increases dramatically when the ion energies are reduced to near-thermal (< 0.1 eV), because of the ion-induced dipole and ion-dipole interaction. These considerations suggest that chemical reaction can be orders of magnitude more efficient at improving the analyte signal/background ratio than can collisional fragmentation. Considerations that lead to an appropriate selection of type of gas, operating pressure, and ion energies for efficient operation of the cell for the alleviation of spectral interferences are discussed. High efficiency (large differences between reaction efficiencies of the analyte and interference ions, and concomitant suppression of secondary chemistry) might be required to optimize the chemical resolution (determination of an analyte in the presence of an isobaric interference) when using ion-molecule chemistry to suppress the interfering ion. In many instances atom transfer to the analyte, which shifts the analytical m/z by the mass of the atom transferred, provides high chemical resolution, even when the efficiency of reaction is relatively low. Examples are given of oxidation, hydroxylation, and chlorination of analyte ions (V+, Fe+, As+, Se+, Sr+, Y+, and Zr+) to improve the capability of determination of complex samples. Preliminary results are given showing O-atom abstraction by CO from CaO+ to enable the determination of Fe in high-Ca samples.

  1. Light-front representation of chiral dynamics with Δ isobar and large- N c relations

    NASA Astrophysics Data System (ADS)

    Granados, C.; Weiss, C.

    2016-06-01

    Transverse densities describe the spatial distribution of electromagnetic current in the nucleon at fixed light-front time. At peripheral distances b = O( M π - 1 ) the densities are governed by chiral dynamics and can be calculated model-independently using chiral effective field theory (EFT). Recent work has shown that the EFT results can be represented in first-quantized form, as overlap integrals of chiral light-front wave functions describing the transition of the nucleon to soft-pion-nucleon intermediate states, resulting in a quantum-mechanical picture of the peripheral transverse densities. We now extend this representation to include intermediate states with Δ isobars and implement relations based on the large- N c limit of QCD. We derive the wave function overlap formulas for the Δ contributions to the peripheral transverse densities by way of a three-dimensional reduction of relativistic chiral EFT expressions. Our procedure effectively maintains rotational invariance and avoids the ambiguities with higher-spin particles in the light-front time-ordered approach. We study the interplay of π N and πΔ intermediate states in the quantum-mechanical picture of the densities in a transversely polarized nucleon. We show that the correct N c -scaling of the charge and magnetization densities emerges as the result of the particular combination of currents generated by intermediate states with degenerate N and Δ. The off-shell behavior of the chiral EFT is summarized in contact terms and can be studied easily. The methods developed here can be applied to other peripheral densities and to moments of the nucleon's generalized parton distributions.

  2. A Transiting Jupiter Analog

    NASA Astrophysics Data System (ADS)

    Kipping, D. M.; Torres, G.; Henze, C.; Teachey, A.; Isaacson, H.; Petigura, E.; Marcy, G. W.; Buchhave, L. A.; Chen, J.; Bryson, S. T.; Sandford, E.

    2016-04-01

    Decadal-long radial velocity surveys have recently started to discover analogs to the most influential planet of our solar system, Jupiter. Detecting and characterizing these worlds is expected to shape our understanding of our uniqueness in the cosmos. Despite the great successes of recent transit surveys, Jupiter analogs represent a terra incognita, owing to the strong intrinsic bias of this method against long orbital periods. We here report on the first validated transiting Jupiter analog, Kepler-167e (KOI-490.02), discovered using Kepler archival photometry orbiting the K4-dwarf KIC-3239945. With a radius of (0.91+/- 0.02) {R}{{J}}, a low orbital eccentricity ({0.06}-0.04+0.10), and an equilibrium temperature of (131+/- 3) K, Kepler-167e bears many of the basic hallmarks of Jupiter. Kepler-167e is accompanied by three Super-Earths on compact orbits, which we also validate, leaving a large cavity of transiting worlds around the habitable-zone. With two transits and continuous photometric coverage, we are able to uniquely and precisely measure the orbital period of this post snow-line planet (1071.2323 ± 0.0006d), paving the way for follow-up of this K = 11.8 mag target.

  3. The Analogy Theme in Geography.

    ERIC Educational Resources Information Center

    Andrews, Alice C.

    1987-01-01

    Describes ten types of analogies and the role they play in thinking and learning. Devotes specific attention to the use of analogies in geography instruction. Claims that the use of analogies in teaching physical, cultural, and regional geography helps students absorb knowledge quickly and integrate it into their existing frameworks. (JDH)

  4. Analogical scaffolding: Making meaning in physics through representation and analogy

    NASA Astrophysics Data System (ADS)

    Podolefsky, Noah Solomon

    This work reviews the literature on analogy, introduces a new model of analogy, and presents a series of experiments that test and confirm the utility of this model to describe and predict student learning in physics with analogy. Pilot studies demonstrate that representations (e.g., diagrams) can play a key role in students' use of analogy. A new model of analogy, Analogical Scaffolding, is developed to explain these initial empirical results. This model will be described in detail, and then applied to describe and predict the outcomes of further experiments. Two large-scale (N>100) studies will demonstrate that: (1) students taught with analogies, according to the Analogical Scaffolding model, outperform students taught without analogies on pre-post assessments focused on electromagnetic waves; (2) the representational forms used to teach with analogy can play a significant role in student learning, with students in one treatment group outperforming students in other treatment groups by factors of two or three. It will be demonstrated that Analogical Scaffolding can be used to predict these results, as well as finer-grained results such as the types of distracters students choose in different treatment groups, and to describe and analyze student reasoning in interviews. Abstraction in physics is reconsidered using Analogical Scaffolding. An operational definition of abstraction is developed within the Analogical Scaffolding framework and employed to explain (a) why physicists consider some ideas more abstract than others in physics, and (b) how students conceptions of these ideas can be modeled. This new approach to abstraction suggests novel approaches to curriculum design in physics using Analogical Scaffolding.

  5. Neural Analog Information Processing

    NASA Astrophysics Data System (ADS)

    Hecht-Nielsen, Robert

    1982-07-01

    Neural Analog Information Processing (NAIP) is an effort to develop general purpose pattern classification architectures based upon biological information processing principles. This paper gives an overview of NAIP and its relationship to the previous work in neural modeling from which its fundamental principles are derived. It also presents a theorem concerning the stability of response of a slab (a two dimensional array of identical simple processing units) to time-invariant (spatial) patterns. An experiment (via computer emulation) demonstrating classification of a spatial pattern by a simple, but complete NAIP architecture is described. A concept for hardware implementation of NAIP architectures is briefly discussed.

  6. A Biochemical Double Slit

    NASA Astrophysics Data System (ADS)

    Kominis, Iannis

    2011-03-01

    Radical-ion-pair reactions, fundamental in photosynthesis and at the basis of the avian magnetic compass mechanism, have been recently shown to offer a rich playground for applying methods and concepts from quantum measurement/quantum information science. We will demonstrate that radical-ion-pair reactions are almost the exact analog of the optical double slit experiment, i.e. Nature has already engineered biochemical reactions performing the act of quantum interference. We will further elaborate on the non-trivial quantum effects pertaining in these reactions and the recent debate on their fundamental theoretical description that these effects have sparked.

  7. Antarctic Space Analog Program

    NASA Technical Reports Server (NTRS)

    Palinkas, Lawrence A; Gunderson, E. K. Eric; Johnson, Jeffrey C.; Holland, Albert W.

    1998-01-01

    The primary aim of this project was to examine group dynamics and individual performance in extreme, isolated environments and identify human factors requirements for long-duration space missions using data collected in an analog environment. Specifically, we wished to determine: 1) the characteristics of social relations in small groups of individuals living and working together in extreme, isolated environments, and 2) the environmental, social and psychological determinants of performance effectiveness in such groups. These two issues were examined in six interrelated studies using data collected in small, isolated research stations in Antarctica from 1963 to the present. Results from these six studies indicated that behavior and performance on long-duration space flights is likely to be seasonal or cyclical, situational, social, and salutogenic in nature. The project responded to two NASA program emphases for FY 1997 as described in the NRA: 1) the primary emphasis of the Behavior and Performance Program on determining long-term individual and group performance responses to space, identifying critical factors affecting those responses and understanding underlying mechanisms involved in behavior and performance, and developing and using ground-based models and analogs for studying space-related behavior and performance; and 2) the emphasis of the Data Analysis Program on extended data analysis. Results from the study were used to develop recommendations for the design and development of pre-flight crew training and in-flight psychological countermeasures for long-duration manned space missions.

  8. Limits of the energy-spin phase space beyond the proton drip line : entry distributions fo Pt and Au isobars.

    SciTech Connect

    Smith, M. B.; Cizewski, J. A.; Carpenter, M. P.; Kondev, F. G.; Khoo, T. L.; Lauritsen, T.; Janssens, R. V. F.; Abu Saleem, K.; Ahmad, I.; Amro, H.; Danchev, M.; Davids, C. N.; Hartley, D. J.; Heinz, A.; Lister, C. J.; Ma, W. C.; Poli, G. L.; Ressler, J. J.; Reviol, W.; Riedinger, L. L.; Seweryniak, D.; Wiedenhoever, I.; Rutgers univ.; Illinois Inst. of Tech.; Mississippi State Univ.; Univ. of Tennessee; Univ. of Maryland; Washington Univ.

    2003-01-09

    Entry distributions in angular momentum and excitation energy have been measured for several very proton-rich isotopes of Pt and Au. This is the first systematic study of the energy-spin phase space for nuclei near and beyond the proton drip line. Comparisons are made between the distributions associated with proton-unbound Au nuclei and more stable Pt isobars. In {sup 173}Au the first evidence is seen for the limits of excitation energy and angular momentum which a nucleus beyond the proton drip line can sustain.

  9. Misleading measures in Vitamin D analysis: a novel LC-MS/MS assay to account for epimers and isobars.

    PubMed

    Shah, Iltaf; James, Ricky; Barker, James; Petroczi, Andrea; Naughton, Declan P

    2011-05-14

    Recently, the accuracies of many commercially available immunoassays for Vitamin D have been questioned. Liquid chromatography tandem mass spectrometry (LC- MS/MS) has been shown to facilitate accurate separation and quantification of the major circulating metabolite 25-hydroxyvitamin-D3 (25OHD3) and 25-hydroxyvitamin-D2 (25OHD2) collectively termed as 25OHD. However, among other interferents, this method may be compromised by overlapping peaks and identical masses of epimers and isobars, resulting in inaccuracies in circulating 25OHD measurements. The aim of this study was to develop a novel LC-MS/MS method that can accurately identify and quantitate 25OHD3 and 25OHD2 through chromatographic separation of 25OHD from its epimers and isobars. A positive ion electrospray ionisation (ESI) LC-MS/MS method was used in the Multiple Reaction Monitoring (MRM) mode for quantification. It involved i) liquid-liquid extraction, ii) tandem columns (a high resolution ZORBAX C18 coupled to an ULTRON chiral, with guard column and inlet filter), iii) Stanozolol-D3 as internal standard, and iv) identification via ESI and monitoring of three fragmentation transitions. To demonstrate the practical usefulness of our method, blood samples were collected from 5 healthy male Caucasian volunteers; age range 22 to 37 years and 25OHD2, 25OHD3 along with co-eluting epimers and analogues were quantified. The new method allowed chromatographic separation and quantification of 25OHD2, 25OHD3, along with 25OHD3 epimer 3-epi-25OHD3 and isobars 1-α-hydroxyvitamin-D3 (1αOHD3), and 7-α-hydroxy-4-cholesten-3-one (7αC4). The new assay was capable of detecting 0.25 ng/mL of all analytes in serum. To our knowledge, this is the first specific, reliable, reproducible and robust LC-MS/MS method developed for the accurate detection of 25OHD (Vitamin D). The method is capable of detecting low levels of 25OHD3 and 25OHD2 together with chromatographic separation from the co-eluting epimers and isobars and

  10. Mars inflatable greenhouse analog.

    PubMed

    Sadler, Philip D; Giacomelli, Gene A

    2002-01-01

    Light intensities on the Martian surface can possibly support a bioregenerative life support system (BLSS) utilizing natural sunlight for hydroponic crop production, if a suitable controlled environment can be provided. Inflatable clear membrane structures offer low mass, are more easily transported than a rigid structure, and are good candidates for providing a suitable controlled environment for crop production. Cable culture is one hydroponic growing system that can take advantage of the beneficial attributes of the inflatable structure. An analog of a Mars inflatable greenhouse can provide researchers data on issues such as crew time requirements for operation, productivity for BLSS, human factors, and much more at a reasonable cost. This is a description of one such design.

  11. Female analogies to perversion.

    PubMed

    Beier, K M

    2000-01-01

    Unlike the intrapsychic mechanism for self-esteem regulation in males as a basic component of perversion--extrapsychically (compensationally) culminating in an output of sexual impulses--a functional stabilization of the female self-concept seems more likely if conflict drives were to be focused on reproductional aspects and not on sexuality. It therefore seems more suitable to use a new expression in linguistic analogy to perversion: "reproversion." The case history gives an example of a clinical manifestation of "reproverse" symptom formation. The general survey describes the main points of view in regard to clinically oriented differentiation, i.e., intensity, ego-proximity in the personality structure, and one's own self-acceptance within "reproverse" symptom formation. Underlying personality disturbances are also discussed. The significance of reproversion is relevant to many different specialized medical fields. This is explained in conclusion, using the examples of denied pregnancy and infanticide at birth based on initial empirical results.

  12. Large-Scale and Deep Quantitative Proteome Profiling Using Isobaric Labeling Coupled with Two-Dimensional LC-MS/MS

    SciTech Connect

    Gritsenko, Marina A.; Xu, Zhe; Liu, Tao; Smith, Richard D.

    2016-02-12

    Comprehensive, quantitative information on abundances of proteins and their post-translational modifications (PTMs) can potentially provide novel biological insights into diseases pathogenesis and therapeutic intervention. Herein, we introduce a quantitative strategy utilizing isobaric stable isotope-labelling techniques combined with two-dimensional liquid chromatography-tandem mass spectrometry (2D-LC-MS/MS) for large-scale, deep quantitative proteome profiling of biological samples or clinical specimens such as tumor tissues. The workflow includes isobaric labeling of tryptic peptides for multiplexed and accurate quantitative analysis, basic reversed-phase LC fractionation and concatenation for reduced sample complexity, and nano-LC coupled to high resolution and high mass accuracy MS analysis for high confidence identification and quantification of proteins. This proteomic analysis strategy has been successfully applied for in-depth quantitative proteomic analysis of tumor samples, and can also be used for integrated proteome and PTM characterization, as well as comprehensive quantitative proteomic analysis across samples from large clinical cohorts.

  13. Thermodynamic properties of supercritical n-m Lennard-Jones fluids and isochoric and isobaric heat capacity maxima and minima

    NASA Astrophysics Data System (ADS)

    Mairhofer, Jonas; Sadus, Richard J.

    2013-10-01

    Molecular dynamics simulations are reported for the thermodynamic properties of n-m Lennard-Jones fluids, where n = 10 and 12, and m = 5 and 6. Results are reported for the thermal expansion coefficient, isothermal and adiabatic compressibilities, isobaric and isochoric heat capacities, Joule-Thomson coefficient, and speed of sound at supercritical conditions covering a wide range of fluid densities. The thermodynamic criteria for maxima/minima in the isochoric and isobaric heat capacities are identified and the simulation results are also compared with calculations from Lennard-Jones equations of state. The Johnson et al. [Mol. Phys. 78, 591 (1993)] equation of state can be used to reproduce all heat capacity phenomena reported [T. M. Yigzawe and R. J. Sadus, J. Chem. Phys. 138, 194502 (2013)] from molecular dynamics simulations for the 12-6 Lennard-Jones potential. Significantly, these calculations and molecular dynamics results for other n-m Lennard-Jones potentials support the existence of Cp minima at supercritical conditions. The values of n and m also have a significant influence on many other thermodynamic properties.

  14. Thermodynamic properties of supercritical n-m Lennard-Jones fluids and isochoric and isobaric heat capacity maxima and minima.

    PubMed

    Mairhofer, Jonas; Sadus, Richard J

    2013-10-21

    Molecular dynamics simulations are reported for the thermodynamic properties of n-m Lennard-Jones fluids, where n = 10 and 12, and m = 5 and 6. Results are reported for the thermal expansion coefficient, isothermal and adiabatic compressibilities, isobaric and isochoric heat capacities, Joule-Thomson coefficient, and speed of sound at supercritical conditions covering a wide range of fluid densities. The thermodynamic criteria for maxima∕minima in the isochoric and isobaric heat capacities are identified and the simulation results are also compared with calculations from Lennard-Jones equations of state. The Johnson et al. [Mol. Phys. 78, 591 (1993)] equation of state can be used to reproduce all heat capacity phenomena reported [T. M. Yigzawe and R. J. Sadus, J. Chem. Phys. 138, 194502 (2013)] from molecular dynamics simulations for the 12-6 Lennard-Jones potential. Significantly, these calculations and molecular dynamics results for other n-m Lennard-Jones potentials support the existence of Cp minima at supercritical conditions. The values of n and m also have a significant influence on many other thermodynamic properties.

  15. Mathematical problem solving by analogy.

    PubMed

    Novick, L R; Holyoak, K J

    1991-05-01

    We report the results of 2 experiments and a verbal protocol study examining the component processes of solving mathematical word problems by analogy. College students first studied a problem and its solution, which provided a potential source for analogical transfer. Then they attempted to solve several analogous problems. For some problems, subjects received one of a variety of hints designed to reduce or eliminate the difficulty of some of the major processes hypothesized to be involved in analogical transfer. Our studies yielded 4 major findings. First, the process of mapping the features of the source and target problems and the process of adapting the source solution procedure for use in solving the target problem were clearly distinguished: (a) Successful mapping was found to be insufficient for successful transfer and (b) adaptation was found to be a major source of transfer difficulty. Second, we obtained direct evidence that schema induction is a natural consequence of analogical transfer. The schema was found to co-exist with the problems from which it was induced, and both the schema and the individual problems facilitated later transfer. Third, for our multiple-solution problems, the relation between analogical transfer and solution accuracy was mediated by the degree of time pressure exerted for the test problems. Finally, mathematical expertise was a significant predictor of analogical transfer, but general analogical reasoning ability was not. The implications of the results for models of analogical transfer and for instruction were considered.

  16. [Analogies and analogy research in technical biology and bionics].

    PubMed

    Nachtigall, Werner

    2010-01-01

    The procedural approaches of Technical Biology and Bionics are characterized, and analogy research is identified as their common basis. The actual creative aspect in bionical research lies in recognizing and exploiting technically oriented analogies underlying a specific biological prototype to indicate a specific technical application.

  17. A randomized controlled study comparing intrathecal hyperbaric bupivacaine-fentanyl mixture and isobaric bupivacaine-fentanyl mixture in common urological procedures

    PubMed Central

    Upadya, Madhusudan; Neeta, S; Manissery, Jesni Joseph; Kuriakose, Nigel; Singh, Rakesh Raushan

    2016-01-01

    Background and Aims: Bupivacaine is available in isobaric and hyperbaric forms for intrathecal use and opioids are used as additives to modify their effects. The aim of this study was to compare the efficacy and haemodynamic effect of intrathecal isobaric bupivacaine-fentanyl mixture and hyperbaric bupivacaine-fentanyl mixture in common urological procedures. Methods: One hundred American Society of Anesthesiologists physical status 1 and 2 patients undergoing urological procedures were randomized into two groups. Group 1 received 3 ml of 0.5% isobaric bupivacaine with 25 μg fentanyl while Group 2 received 3 ml of 0.5% hyperbaric bupivacaine with 25 μg fentanyl. The parameters measured include heart rate, blood pressure, respiratory rate, onset and duration of motor and sensory blockade. Student's unpaired t-test and the χ2 test were used to analyse the results, using the SPSS version 11.5 software. Results: The haemodynamic stability was better with isobaric bupivacaine fentanyl mixture (Group 1) than with hyperbaric bupivacaine fentanyl mixture (Group 2). The mean onset time in Group 1 for both sensory block (4 min) and motor block (5 min) was longer compared with Group 2. The duration of sensory block (127.8 ± 38.64 min) and motor block (170.4 ± 27.8 min) was less with isobaric bupivacaine group compared with hyperbaric bupivacaine group (sensory blockade 185.4 ± 16.08 min and motor blockade 201.6 ± 14.28 min). Seventy percent of patients in Group 2 had maximum sensory block level of T6 whereas it was 53% in Group 1. More patients in Group 1 required sedation compared to Group 2. Conclusion: Isobaric bupivacaine fentanyl mixture was found to provide adequate anaesthesia with minimal incidence of haemodynamic instability. PMID:26962255

  18. Natural analog studies: Licensing perspective

    SciTech Connect

    Bradbury, J.W.

    1995-09-01

    This report describes the licensing perspective of the term {open_quotes}natural analog studies{close_quotes} as used in CFR Part 60. It describes the misunderstandings related to its definition which has become evident during discussions at the U.S Nuclear Regulatory Commission meetings and tries to clarify the appropriate applications of natural analog studies to aspects of repository site characterization.

  19. Drawing Analogies in Environmental Education

    ERIC Educational Resources Information Center

    Affifi, Ramsey

    2014-01-01

    Reconsidering the origin, process, and outcomes of analogy-making suggests practices for environmental educators who strive to disengage humans from the isolating illusions of dichotomizing frameworks. We can view analogies as outcomes of developmental processes within which human subjectivity is but an element, threading our sense of self back…

  20. Drawing Analogies in Environmental Education

    ERIC Educational Resources Information Center

    Affifi, Ramsey

    2014-01-01

    Reconsidering the origin, process, and outcomes of analogy-making suggests practices for environmental educators who strive to disengage humans from the isolating illusions of dichotomizing frameworks. We can view analogies as outcomes of developmental processes within which human subjectivity is but an element, threading our sense of self back…

  1. Conjecturing via Reconceived Classical Analogy

    ERIC Educational Resources Information Center

    Lee, Kyeong-Hwa; Sriraman, Bharath

    2011-01-01

    Analogical reasoning is believed to be an efficient means of problem solving and construction of knowledge during the search for and the analysis of new mathematical objects. However, there is growing concern that despite everyday usage, learners are unable to transfer analogical reasoning to learning situations. This study aims at facilitating…

  2. Conjecturing via Reconceived Classical Analogy

    ERIC Educational Resources Information Center

    Lee, Kyeong-Hwa; Sriraman, Bharath

    2011-01-01

    Analogical reasoning is believed to be an efficient means of problem solving and construction of knowledge during the search for and the analysis of new mathematical objects. However, there is growing concern that despite everyday usage, learners are unable to transfer analogical reasoning to learning situations. This study aims at facilitating…

  3. Analog pixel array detectors.

    PubMed

    Ercan, A; Tate, M W; Gruner, S M

    2006-03-01

    X-ray pixel array detectors (PADs) are generally thought of as either digital photon counters (DPADs) or X-ray analog-integrating pixel array detectors (APADs). Experiences with APADs, which are especially well suited for X-ray imaging experiments where transient or high instantaneous flux events must be recorded, are reported. The design, characterization and experimental applications of several APAD designs developed at Cornell University are discussed. The simplest design is a ;flash' architecture, wherein successive integrated X-ray images, as short as several hundred nanoseconds in duration, are stored in the detector chips for later off-chip digitization. Radiography experiments using a prototype flash APAD are summarized. Another design has been implemented that combines flash capability with the ability to continuously stream X-ray images at slower (e.g. milliseconds) rates. Progress is described towards radiation-hardened APADs that can be tiled to cover a large area. A mixed-mode PAD, design by combining many of the attractive features of both APADs and DPADs, is also described.

  4. The feasibility of isobaric suppression of 26Mg via post-accelerator foil stripping for the measurement of 26Al [The feasibility of isobaric suppression of 26Mg via post-accelerator foil stripping for the measurement of 26Al.

    DOE PAGES

    Tumey, Scott J.; Brown, Thomas A.; Finkel, Robert C.; ...

    2012-09-13

    Most accelerator mass spectrometry measurements of 26Al utilize the Al- ion despite lower source currents compared with AlO- since the stable isobar 26Mg does not form elemental negative ions. A gas-filled magnet allows sufficient suppression of 26Mg thus enabling the use of the more intense 26AlO- ion. However, most AMS systems do not include a gas-filled magnet. We therefore explored the feasibility of suppressing 26Mg by using a post-accelerator stripping foil. With this approach, combined with the use of alternative cathode matrices, we were able to suppress 26Mg by a factor of twenty. This suppression was insufficient to enable themore » use of 26AlO-, however further refinement of our system may permit its use in the future.« less

  5. Cannabinoid properties of methylfluorophosphonate analogs.

    PubMed

    Martin, B R; Beletskaya, I; Patrick, G; Jefferson, R; Winckler, R; Deutsch, D G; Di Marzo, V; Dasse, O; Mahadevan, A; Razdan, R K

    2000-09-01

    Methylarachidonylfluorophosphonate (MAFP) and related analogs have been shown to inhibit fatty acid amidohydrolase activity (FAAH), the enzyme responsible for hydrolysis of the endogenous cannabinoid ligand anandamide. To fully characterize this class of compounds, methylfluorophosphonate compounds with saturated alkyl chains ranging from C8 to C20 along with C20 unsaturated derivatives were synthesized and evaluated for their ability to interact with the CB1 receptor, inhibit FAAH, and produce in vivo pharmacological effects. These analogs demonstrated widely varying affinities for the CB1 receptor. Of the saturated compounds, C8:0 was incapable of displacing [(3)H]CP 55,940 binding, whereas C12:0 exhibited high affinity (2.5 nM). The C20:0 saturated analog had low affinity (900 nM), but the introduction of unsaturation into the C20 analogs restored receptor affinity. However, none of the analogs were capable of fully displacing [(3)H]CP 55,940 binding. On the other hand, all compounds were able to completely inhibit FAAH enzyme activity, with the C20:0 analog being the least potent. The most potent FAAH inhibitor was the short-chained saturated C12:0, whereas the other analogs were 15- to 30-fold less potent. In vivo, the C8:0 and C12:0 analogs were highly potent and fully efficacious in producing tetrahydrocannabinol (THC)-like effects, whereas the other analogs were either inactive or acted as partial agonists. None was capable of attenuating the agonist effects of THC. Conversely, the C20:0 analog potentiated the effects of anandamide but not those of 2-arachidonoyl-glycerol and THC. The high in vivo potency of the novel short-chain saturated MAFP derivatives (C8:0 and C12:0) underscores the complexity of manipulating the endogenous cannabinoid system.

  6. An Analog Earth Climate Model

    NASA Astrophysics Data System (ADS)

    Varekamp, J. C.

    2010-12-01

    The earth climate is broadly governed by the radiative power of the sun as well as the heat retention and convective cooling of the atmosphere. I have constructed an analog earth model for an undergraduate climate class that simulates mean climate using these three parameters. The ‘earth’ is a hollow, black, bronze sphere (4 cm diameter) mounted on a thin insulated rod, and illuminated by two opposite optic fibers, with light focused on the sphere by a set of lenses. The sphere is encased in a large double-walled aluminum cylinder (34 cm diameter by 26 cm high) with separate water cooling jackets at the top, bottom, and sides. The cylinder can be filled with a gas of choice at a variety of pressures or can be run in vacuum. The exterior is cladded with insulation, and the temperature of the sphere, atmosphere and walls is monitored with thermocouples. The temperature and waterflow of the three cooling jackets can be monitored to establish the energy output of the whole system; the energy input is the energy yield of the two optic fibers. A small IR transmissive lens at the top provides the opportunity to hook up the fiber of a hyper spectrometer to monitor the emission spectrum of the black ‘earth’ sphere. A pressure gauge and gas inlet-outlet system for flushing of the cell completes it. The heat yield of the cooling water at the top is the sum of the radiative and convective components, whereas the bottom jacket only carries off the radiative heat of the sphere. Undergraduate E&ES students at Wesleyan University have run experiments with dry air, pure CO2, N2 and Ar at 1 atmosphere, and a low vacuum run was accomplished to calibrate the energy input. For each experiment, the lights are flipped on, the temperature acquisition routine is activated, and the sphere starts to warm up until an equilibrium temperature has been reached. The lights are then flipped off and the cooling sequence towards ambient is registered. The energy input is constant for a given

  7. Spectroscopy of the neutron-deficient isobars {sup 163}Re and {sup 163}W using tagging techniques

    SciTech Connect

    Joss, D. T.; Thomson, J.; Page, R. D.; Bianco, L.; Darby, I. G.; Grahn, T.; Pakarinen, J.; Paul, E. S.; Scholey, C.; Eeckhaudt, S.; Greenlees, P. T.; Jones, P. M.; Julin, R.; Juutinen, S.; Ketelhut, S.; Leino, M.; Leppaennen, A.-P.; Nyman, M.; Rahkila, P.; Sorri, J.

    2008-11-11

    Selective tagging techniques have been used to establish new band structures in the transitional isobars {sup 163}Re and {sup 163}W. These nuclei were produced in the {sup 106}Cd({sup 60}Ni, xp yn {gamma}) reaction at a bombarding energy of 270 MeV. Prompt {gamma} rays were detected at the target position using the JUROGAM spectrometer while recoiling ions were separated by the RITU separator and implanted into the GREAT spectrometer. At low spin, the yrast band of {sup 163}Re is shown to be a strongly coupled collective band based on a proton h{sub 11/2} configuration. In {sup 163}W, the decay path of the 13/2{sup +} isomeric state to the ground state has been identified and negative parity structures based on the ground state established.

  8. Realistic calculations for c coefficients of the isobaric mass multiplet equation in 1 p 0 f shell nuclei

    NASA Astrophysics Data System (ADS)

    Ormand, W. E.; Brown, B. A.; Hjorth-Jensen, M.

    2017-08-01

    We present calculations for the c coefficients of the isobaric mass multiplet equation for nuclei from A =42 to A =54 based on input from three realistic nucleon-nucleon interactions. We demonstrate that there is a clear dependence on the short-range charge-symmetry-breaking (CSB) part of the strong interaction and that there is significant disagreement in the CSB part between the commonly used CD-Bonn, chiral effective field theory at next-to-next-to-next-to-leading-order, and Argonne V18 nucleon-nucleon interactions. In addition, we show that all three interactions give a CSB contribution to the c coefficient that is too large when compared to experiment.

  9. A vibrational spectroscopic study of structure evolution of water dissolved in supercritical carbon dioxide under isobaric heating.

    PubMed

    Oparin, R; Tassaing, T; Danten, Y; Besnard, M

    2004-06-08

    A combination of Raman scattering spectroscopy and infrared absorption was applied to investigate the structural evolution of water dissolved in supercritical carbon dioxide under isobaric heating (T=40-340 degrees C, P=250 bar). Quantitative analysis of experimental spectra allowed us to determine that at relatively moderate temperatures water dissolved in CO(2)-rich phase exists only under monomeric form (solitary water surrounding by CO(2) molecules), but hydrogen-bonded species, namely, dimers, begin to appear upon heating. At the same time, the ratio of dimers to monomers concentration increases with further temperature increase and at temperatures close to the temperature of total miscibility of the mixture (T=366 degrees C, P=250 bar), water dimers only are present in the CO(2)-rich phase. (c) 2004 American Institute of Physics.

  10. Structure- and isoform-specific glucuronidation of six curcumin analogs.

    PubMed

    Lu, Danyi; Liu, Hui; Ye, Wencai; Wang, Ying; Wu, Baojian

    2017-04-01

    1. In the present study, we aimed to characterize the glucuronidation of six curcumin analogs (i.e. RAO-3, RAO-8, RAO-9, RAO-18, RAO-19, and RAO-23) derived from galangal using human liver microsomes (HLM) and twelve expressed UGT enzymes. 2. Formation of glucuronide was confirmed using high-resolution mass spectrometry. Single glucuronide metabolite was generated from each of six curcumin analogs. The fragmentation patterns were analyzed and were found to differ significantly between alcoholic and phenolic glucuronides. 3. All six curcumin analogs except one (RAO-23) underwent significant glucuronidation in HLM and expressed UGT enzymes. In general, the methoxy group (close to the phenolic hydroxyl group) enhanced the glucuronidation liability of the curcumin analogs. 4. UGT1A9 and UGT2B7 were primarily responsible for the glucuronidation of two alcoholic analogs (RAO-3 and RAO-18). By contrast, UGT1A9 and four UGT2Bs (UGT2B4, 2B7, 2B15 and 2B17) played important roles in conjugating three phenolic analogs (RAO-8, RAO-9, and RAO-19). Interestingly, the conjugated double bonds system (in the aliphatic chain) was crucial to the substrate selectivity of gastrointestinal UGTs (i.e. UGT1A7, 1A8 and 1A10). 5. In conclusion, glucuronidation of six curcumin analogs from galangal were structure- and isoform-specific. The knowledge should be useful in identifying a curcumin analog with improved metabolic property.

  11. Orthographic analogies and developmental dyslexia.

    PubMed

    Hanley, J R; Reynolds, C J; Thornton, A

    1997-08-01

    Goswami (1986, 1988) has demonstrated that children can use orthographic analogies (particularly at the onset-rime level) between the spelling patterns in words to help to decode new words (e.g. using 'beak' to read 'peak'). This strategy has been shown in children as young as six years old. Since it is known that children with developmental dyslexia find it particularly difficult to read words that they have not been specifically taught (Lovett, Warren-Chaplin, Ransby & Borden, 1990), the present study investigated whether dyslexic children might be unable to use analogies. Employing a design similar to that used by Goswami (1988), it was hypothesized that dyslexics would find it difficult to transfer spontaneously knowledge of a 'clue' word to decode new words that could be read by analogy with the clue word. The results of Expt 1 indicated that the dyslexic readers read significantly fewer of the analogous words than a reading age-matched comparison group of younger children. Furthermore, none of the nine dyslexic children read as many of the analogous words as the lowest scoring control child. In a second experiment, a design similar to that of Muter, Snowling & Taylor (1994) was used with a new and larger sample of dyslexic children. In this experiment, all the children were brought to criterion in reading the clue words before the analogous words were presented. Once again, the dyslexic children read significantly fewer words that were analogous with the clue words than did a reading age-matched comparison group. The number of analogous words that the dyslexic children read was significantly correlated with their performance on a test that is sensitive to the ability to detect rhyme. It is argued that a failure to make analogies may be one of the main causes of the reading impairment experienced by children with developmental dyslexia.

  12. Development and characterization of novel 8-plex DiLeu isobaric labels for quantitative proteomics and peptidomics

    PubMed Central

    Frost, Dustin C.; Greer, Tyler; Xiang, Feng; Liang, Zhidan; Li, Lingjun

    2015-01-01

    Rationale Relative quantification of proteins via their enzymatically digested peptide products determines disease biomarker candidate lists in discovery studies. Isobaric label-based strategies using TMT and iTRAQ allow for up to 10 samples to be multiplexed in one experiment, but their expense limits their use. The demand for cost-effective tagging reagents capable of multiplexing many samples led us to develop an 8-plex version of our isobaric labeling reagent, DiLeu. Methods The original 4-plex DiLeu reagent was extended to an 8-plex set by coupling isotopic variants of dimethylated leucine to an alanine balance group designed to offset the increasing mass of the label’s reporter group. Tryptic peptides from a single protein digest, a protein mixture digest, and Saccharomyces cerevisiae lysate digest were labeled with 8-plex DiLeu and analyzed via nanoLC-MS2 on a Q-Exactive Orbitrap mass spectrometer. Characteristics of 8-plex DiLeu-labeled peptides, including quantitative accuracy and fragmentation, were examined. Results An 8-plex set of DiLeu reagents with 1 Da-spaced reporters was synthesized at a yield of 36%. The average cost to label eight 100 μg peptide samples was calculated to be approximately $15. Normalized collision energy tests on the Q-Exactive revealed that a higher-energy collisional dissociation value of 27 generated the optimum number of high-quality spectral matches. Relative quantification of DiLeu-labeled peptides yielded normalized median ratios accurate to within 12% of their expected values. Conclusions Cost-effective 8-plex DiLeu reagents can be synthesized and applied to relative peptide and protein quantification. These labels increase the multiplexing capacity of our previous 4-plex implementation without requiring high-resolution instrumentation to resolve reporter ion signals. PMID:25981542

  13. Proteomic Identification and Quantification of S-glutathionylation in Mouse Macrophages Using Resin-Assisted Enrichment and Isobaric Labeling

    SciTech Connect

    Su, Dian; Gaffrey, Matthew J.; Guo, Jia; Hatchell, Kayla E.; Chu, Rosalie K.; Clauss, Therese RW; Aldrich, Joshua T.; Wu, Si; Purvine, Samuel O.; Camp, David G.; Smith, Richard D.; Thrall, Brian D.; Qian, Weijun

    2014-02-11

    Protein S-glutathionylation (SSG) is an important regulatory posttranslational modification of protein cysteine (Cys) thiol redox switches, yet the role of specific cysteine residues as targets of modification is poorly understood. We report a novel quantitative mass spectrometry (MS)-based proteomic method for site-specific identification and quantification of S-glutathionylation across different conditions. Briefly, this approach consists of initial blocking of free thiols by alkylation, selective reduction of glutathionylated thiols and enrichment using thiol affinity resins, followed by on-resin tryptic digestion and isobaric labeling with iTRAQ (isobaric tags for relative and absolute quantitation) for MS-based identification and quantification. The overall approach was validated by application to RAW 264.7 mouse macrophages treated with different doses of diamide to induce glutathionylation. A total of 1071 Cys-sites from 690 proteins were identified in response to diamide treatment, with ~90% of the sites displaying >2-fold increases in SSG-modification compared to controls.. This approach was extended to identify potential SSG modified Cys-sites in response to H2O2, an endogenous oxidant produced by activated macrophages and many pathophysiological stimuli. The results revealed 364 Cys-sites from 265 proteins that were sensitive to S-glutathionylation in response to H2O2 treatment. These proteins covered a range of molecular types and molecular functions with free radical scavenging, and cell death and survival included as the most significantly enriched functional categories. Overall the results demonstrate that our approach is effective for site-specific identification and quantification of S-glutathionylated proteins. The analytical strategy also provides a unique approach to determining the major pathways and cell processes most susceptible to glutathionylation at a proteome-wide scale.

  14. Molecular dynamics in the isothermal-isobaric ensemble: the requirement of a "shell" molecule. III. Discontinuous potentials.

    PubMed

    Uline, Mark J; Corti, David S

    2008-07-07

    Based on the approach of Gruhn and Monson [Phys. Rev. E 63, 061106 (2001)], we present a new method for deriving the collisions dynamics for particles that interact via discontinuous potentials. By invoking the conservation of the extended Hamiltonian, we generate molecular dynamics (MD) algorithms for simulating the hard-sphere and square-well fluids within the isothermal-isobaric (NpT) ensemble. Consistent with the recent rigorous reformulation of the NpT ensemble partition function, the equations of motion impose a constant external pressure via the introduction of a shell particle of known mass [M. J. Uline and D. S. Corti, J. Chem. Phys. 123, 164101 (2005); 123, 164102 (2005)], which serves to define uniquely the volume of the system. The particles are also connected to a temperature reservoir through the use of a chain of Nose-Hoover thermostats, the properties of which are not affected by a hard-sphere or square-well collision. By using the Liouville operator formalism and the Trotter expansion theorem to integrate the equations of motion, the update of the thermostat variables can be decoupled from the update of the positions of the particles and the momentum changes upon a collision. Hence, once the appropriate collision dynamics for the isobaric-isenthalpic (NpH) equations of motion is known, the adaptation of the algorithm to the NpT ensemble is straightforward. Results of MD simulations for the pure component square-well fluid are presented and serve to validate our algorithm. Finally, since the mass of the shell particle is known, the system itself, and not a piston of arbitrary mass, controls the time scales for internal pressure and volume fluctuations. We therefore consider the influence of the shell particle algorithm on the dynamics of the square-well fluid.

  15. Proteomic Identification and Quantification of S-glutathionylation in Mouse Macrophages Using Resin-Assisted Enrichment and Isobaric Labeling

    PubMed Central

    Su, Dian; Gaffrey, Matthew J.; Guo, Jia; Hatchell, Kayla E.; Chu, Rosalie K.; Clauss, Therese R. W.; Aldrich, Joshua T.; Wu, Si; Purvine, Sam; Camp, David G.; Smith, Richard D.; Thrall, Brian D.; Qian, Wei-Jun

    2014-01-01

    S-glutathionylation (SSG) is an important regulatory posttranslational modification on protein cysteine (Cys) thiols, yet the role of specific cysteine residues as targets of modification is poorly understood. We report a novel quantitative mass spectrometry (MS)-based proteomic method for site-specific identification and quantification of S-glutathionylation across different conditions. Briefly, this approach consists of initial blocking of free thiols by alkylation, selective reduction of glutathionylated thiols and covalent capture of reduced thiols using thiol affinity resins, followed by on-resin tryptic digestion and isobaric labeling with iTRAQ (isobaric tags for relative and absolute quantitation) for MS-based identification and quantification. The overall approach was initially validated by application to RAW 264.7 mouse macrophages treated with different doses of diamide to induce glutathionylation. A total of 1071 Cys-sites from 690 proteins were identified in response to diamide treatment, with ~90% of the sites displaying >2-fold increases in SSG-modification compared to controls. This approach was extended to identify potential SSG- modified Cys-sites in response to H2O2, an endogenous oxidant produced by activated macrophages and many pathophysiological stimuli. The results revealed 364 Cys-sites from 265 proteins that were sensitive to S-glutathionylation in response to H2O2 treatment, thus providing a database of proteins and Cys-sites susceptible to this modification under oxidative stress. Functional analysis revealed that the most significantly enriched molecular function categories for proteins sensitive to SSG modifications were free radical scavenging and cell death/survival. Overall the results demonstrate that our approach is effective for site-specific identification and quantification of SSG-modified proteins. The analytical strategy also provides a unique approach to determining the major pathways and cellular processes most susceptible

  16. Delta. sub 33 -isobar contribution to the soft nucleon-nucleon potentials. I. 2. pi. -exchange potentials

    SciTech Connect

    Rijken, T.A.; Stoks, V.G.J. )

    1992-07-01

    Two-pion-exchange (TPE) nucleon-nucleon potentials are derived for one or two {Delta} isobars in the intermediate states. Strong dynamical pair suppression is assumed. At the {ital NN}{pi} and the {ital N}{Delta}{pi} vertices Gaussian form factors are incorporated into the relativistic two-body framework by using a dispersion representation for the one-pion-exchange amplitudes. The Fourier transformations are performed using factorization techniques for the energy denominators, taking into account the mass difference between the nucleon and the {Delta} isobar. Analytic expressions for the TPE potentials are obtained, which contain at most one-dimensional integrals. The TPE potentials are first calculated up to orders ({ital f}{sub {ital N}{ital N}{pi}} f{sub {ital N}{Delta}{pi}}){sup 2} and {ital f}{sub {ital N}{Delta}{pi}}{sup 4}. These come from the adiabatic contributions of all planar and crossed three-dimensional momentum-space TPE diagrams. We also give the contributions of the OPE iteration, which can be subtracted or not, depending on whether one performs a coupled-channel calculation for, e.g., the {ital NN}, {ital N}{Delta} system, or a single {ital NN}-channel calculation. Next, we calculate the ({ital m}{sub {pi}}/{ital M}) corrections. These are due to the 1/{ital M} terms in the pion-nucleon vertices, and the 1/{ital M} terms in the nonadiabatic expansion of the nucleon energies in the intermediate states.

  17. Phase noise performance of analog frequency dividers.

    PubMed

    Driscoll, M M

    1990-01-01

    The phase noise performance obtainable using silicon and GaAs-based TTL (transistor-transistor logic) and ECL (emitter-coupled logic) logic level digital frequency dividers is discussed. Measurement of the spectral performance of two types of analog dividers is reported: a parametric divider using varactor diodes and a regenerative-type divider incorporating a double-balanced mixer in the oscillator feedback circuit. Both dividers were configured for divide-by-two operation at VHF. Evaluation indicates the regenerative divider is capable of providing much lower phase noise than conventional digital logic level devices. The regenerative divider can be successfully operated over bandwidths in excess of an octave, and the design lends itself to small (i.e. TO-8) modular package implementation. Operating frequencies are bounded only by the range of the mixer and RF amplifier utilized and, as such, should extend from HF through microwave.

  18. Quantification of Cell-Penetrating Peptide Associated with Polymeric Nanoparticles Using Isobaric-Tagging and MALDI-TOF MS/MS.

    PubMed

    Chiu, Jasper Z S; Tucker, Ian G; McDowell, Arlene

    2016-11-01

    High sensitivity quantification of the putative cell-penetrating peptide di-arginine-histidine (RRH) associated with poly (ethyl-cyanoacrylate) (PECA) nanoparticles was achieved without analyte separation, using a novel application of isobaric-tagging and high matrix-assisted laser desorption/ionization coupled to time-of-flight (MALDI-TOF) mass spectrometry. Isobaric-tagging reaction equilibrium was reached after 5 min, with 90% or greater RRH peptide successfully isobaric-tagged after 60 min. The accuracy was greater than 90%, which indicates good reliability of using isobaric-tagged RRH as an internal standard for RRH quantification. The sample intra- and inter-spot coefficients of variations were less than 11%, which indicate good repeatability. The majority of RRH peptides in the nanoparticle formulation were physically associated with the nanoparticles (46.6%), whereas only a small fraction remained unassociated (13.7%). The unrecovered RRH peptide (~40%) was assumed to be covalently associated with PECA nanoparticles. Graphical Abstract ᅟ.

  19. Double helicenes

    NASA Astrophysics Data System (ADS)

    Bachrach, Steven M.

    2016-12-01

    The even double helicenes with 4-12 phenyl groups in each helix were examined at B3LYP-D3/6-311G(d). The double helicenes with 4-10 phenyl rings are less than twice as strained as their component helicenes; the strain results from twisting about the shared naphthyl moiety, with accompanying loss of aromaticity. These compounds should be reasonable synthetic targets, and computed NMR shifts are provided to aid in their characterization.

  20. Factors Affecting the Difficulty of Verbal Analogies.

    ERIC Educational Resources Information Center

    Roccas, Sonia; Moshinsky, Avital

    2003-01-01

    Examined factors affecting the difficulty of verbal analogies in a psychometric examination by characterizing 104 analogies using 5 defined attributes. Both knowledge and process attributes were found to contribute to the difficulty of verbal analogies assessed by 10 judges. (SLD)

  1. Analog actuator-piston memory

    NASA Technical Reports Server (NTRS)

    Sable, B. A.

    1980-01-01

    Simple analog control system of digitally controlled acuator uses 'stopped' position of actuator as 'memory' and potentiometer as sensing element during power failure to reload drive circuit to value equal to its last position preceding power loss.

  2. Flight Analogs (Bed Rest Research)

    NASA Image and Video Library

    Flight Analogs / Bed Rest Research Projects provide NASA with a ground based research platform to complement space research. By mimicking the conditions of weightlessness in the human body here on ...

  3. Analog device simulates physiological waveforms

    NASA Technical Reports Server (NTRS)

    Hickman, D. M.

    1964-01-01

    An analog physiological simulator generates representative waveforms for a wide range of physiological conditions. Direct comparison of these waveforms with those from telemetric inputs permits quick detection of signal parameter degradation.

  4. Introduction to Analog Field Testing

    NASA Image and Video Library

    NASA tests systems and operational concepts in analog environments, which include locations underwater, in the arctic, on terrestrial impact craters, in the desert, and on the International Space S...

  5. Solving a problem by analogy

    NASA Astrophysics Data System (ADS)

    Easton, Don

    1999-03-01

    This note is a description of a student solution to a problem. I found the solution exciting because it exemplifies the kind of solution by analogy that Feynman describes in The Feynman Lectures on Physics.

  6. Verbal Analogies in the ITPA

    ERIC Educational Resources Information Center

    Levinson, Philip J.; Kunze, Luvern H.

    1973-01-01

    This study examined the extent to which the Auditory Association subtest of the revised Illinois Test of Psycholinguistic Abilities (ITPA) measures the ability of children to complete verbal analogies. (Author)

  7. The Robustness of Acoustic Analogies

    NASA Technical Reports Server (NTRS)

    Freund, J. B.; Lele, S. K.; Wei, M.

    2004-01-01

    Acoustic analogies for the prediction of flow noise are exact rearrangements of the flow equations N(right arrow q) = 0 into a nominal sound source S(right arrow q) and sound propagation operator L such that L(right arrow q) = S(right arrow q). In practice, the sound source is typically modeled and the propagation operator inverted to make predictions. Since the rearrangement is exact, any sufficiently accurate model of the source will yield the correct sound, so other factors must determine the merits of any particular formulation. Using data from a two-dimensional mixing layer direct numerical simulation (DNS), we evaluate the robustness of two analogy formulations to different errors intentionally introduced into the source. The motivation is that since S can not be perfectly modeled, analogies that are less sensitive to errors in S are preferable. Our assessment is made within the framework of Goldstein's generalized acoustic analogy, in which different choices of a base flow used in constructing L give different sources S and thus different analogies. A uniform base flow yields a Lighthill-like analogy, which we evaluate against a formulation in which the base flow is the actual mean flow of the DNS. The more complex mean flow formulation is found to be significantly more robust to errors in the energetic turbulent fluctuations, but its advantage is less pronounced when errors are made in the smaller scales.

  8. New double soft emission theorems

    NASA Astrophysics Data System (ADS)

    Cachazo, Freddy; He, Song; Yuan, Ellis Ye

    2015-09-01

    We study the behavior of the tree-level S-matrix of a variety of theories as two particles become soft. By analogy with the recently found subleading soft theorems for gravitons and gluons, we explore subleading terms in double soft emissions. We first consider double soft scalar emissions and find subleading terms that are controlled by the angular momentum operator acting on hard particles. The order of the subleading theorems depends on the presence or not of color structures. Next we obtain a compact formula for the leading term in a double soft photon emission. The theories studied are a special Galileon, Dirac-Born-Infeld, Einstein-Maxwell-Scalar, nonlinear sigma model and Yang-Mills-Scalar. We use the recently found Cachazo-He-Yuan representation of these theories in order to give a simple proof of the leading order part of all these theorems.

  9. Analog approach to mixed analog-digital circuit simulation

    NASA Astrophysics Data System (ADS)

    Ogrodzki, Jan

    2013-10-01

    Logic simulation of digital circuits is a well explored research area. Most up-to-date CAD tools for digital circuits simulation use an event driven, selective trace algorithm and Hardware Description Languages (HDL), e.g. the VHDL. This techniques enable simulation of mixed circuits, as well, where an analog part is connected to the digital one through D/A and A/D converters. The event-driven mixed simulation applies a unified, digital-circuits dedicated method to both digital and analog subsystems. In recent years HDL techniques have been also applied to mixed domains, as e.g. in the VHDL-AMS. This paper presents an approach dual to the event-driven one, where an analog part together with a digital one and with converters is treated as the analog subsystem and is simulated by means of circuit simulation techniques. In our problem an analog solver used yields some numerical problems caused by nonlinearities of digital elements. Efficient methods for overriding these difficulties have been proposed.

  10. Fuzzy classifier for fault diagnosis in analog electronic circuits.

    PubMed

    Kumar, Ashwani; Singh, A P

    2013-11-01

    Many studies have presented different approaches for the fault diagnosis with fault models having ± 50% variation in the component values in analog electronic circuits. There is still a need of the approaches which provide the fault diagnosis with the variation in the component value below ± 50%. A new single and multiple fault diagnosis technique for soft faults in analog electronic circuit using fuzzy classifier has been proposed in this paper. This technique uses the simulation before test (SBT) approach by analyzing the frequency response of the analog circuit under faulty and fault free conditions. Three signature parameters peak gain, frequency and phase associated with peak gain, of the frequency response of the analog circuit are observed and extracted such that they give unique values for faulty and fault free configuration of the circuit. The single and double fault models with the component variations from ± 10% to ± 50% are considered. The fuzzy classifier along the classification of faults gives the estimated component value under faulty and faultfree conditions. The proposed method is validated using simulated data and the real time data for a benchmark analog circuit. The comparative analysis is also presented for both the validations.

  11. Producing and Recognizing Analogical Relations

    PubMed Central

    Lipkens, Regina; Hayes, Steven C

    2009-01-01

    Analogical reasoning is an important component of intelligent behavior, and a key test of any approach to human language and cognition. Only a limited amount of empirical work has been conducted from a behavior analytic point of view, most of that within Relational Frame Theory (RFT), which views analogy as a matter of deriving relations among relations. The present series of four studies expands previous work by exploring the applicability of this model of analogy to topography-based rather than merely selection-based responses and by extending the work into additional relations, including nonsymmetrical ones. In each of the four studies participants pretrained in contextual control over nonarbitrary stimulus relations of sameness and opposition, or of sameness, smaller than, and larger than, learned arbitrary stimulus relations in the presence of these relational cues and derived analogies involving directly trained relations and derived relations of mutual and combinatorial entailment, measured using a variety of productive and selection-based measures. In Experiment 1 participants successfully recognized analogies among stimulus networks containing same and opposite relations; in Experiment 2 analogy was successfully used to extend derived relations to pairs of novel stimuli; in Experiment 3 the procedure used in Experiment 1 was extended to nonsymmetrical comparative relations; in Experiment 4 the procedure used in Experiment 2 was extended to nonsymmetrical comparative relations. Although not every participant showed the effects predicted, overall the procedures occasioned relational responses consistent with an RFT account that have not yet been demonstrated in a behavior-analytic laboratory setting, including productive responding on the basis of analogies. PMID:19230515

  12. [Double responses].

    PubMed

    Motté, G; Dinanian, S; Sebag, C; Drieu, L; Slama, M

    1995-12-01

    Double response is a rare electrocardiographic phenomenon requiring two atrioventricular conduction pathways with very different electrophysiological properties. Double ventricular responses are the usual manifestation: an atrial depolarisation (spontaneous or provoked, anticipated or not) is followed by a first ventricular response dependent on an accessory pathway or a rapid nodal pathway and then a second response resulting from sufficiently delayed transmission through a nodal pathway for the ventricles to have recovered their excitability when the second wave of activation reaches them. A simple curiosity when isolated and occurring under unusual conditions, particularly during electrophysiological investigation of the Wolff-Parkinson-White syndrome, the double response may initiate symptomatic non-reentrant junctional tachycardia when associated with nodal duality and repeating from atria in sinus rhythm. The functional incapacity and resistance to antiarrhythmic therapy may require referral for ablation of the slow pathway.

  13. Neutron-skin effects in isobaric yield ratios for mirror nuclei in a statistical abrasion-ablation model

    NASA Astrophysics Data System (ADS)

    Ma, Chun-Wang; Wei, Hui-Ling; Ma, Yu-Gang

    2013-10-01

    Background: The isobaric yield ratio for mirror nuclei [IYR(m)] in heavy-ion collisions, which is assumed to depend linearly on x=2(Z-1)/A1/3 of a fragment, is applied to study some coefficients of the energy terms in the binding energy, as well as the difference between the chemical potentials of a neutron and proton. It is found that the IYR(m) has a systematic dependence on the reaction, which has been explained as the volume and/or the isospin effects in previous studies. However, neither the volume nor the isospin effects can fully interpret the data.Purpose: We suppose that the IYR(m) depends on the neutron-skin thickness (δnp) of the projectile, and check the idea of whether the neutron-skin thickness effects can fully explain the systematic dependence of the IYR(m).Methods: A modified statistical abrasion-ablation model is used to calculate the reactions induced by projectiles of three series: (1) the calcium isotopes from 36Ca to 56Ca as projectiles with different limitations on the impact parameters (bmax) to show the volume effects according to bmax; (2) the A=45 isobars as the projectiles having different isospins and δnp; and (3) projectiles having similar δnp to show whether the IYR(m) depends on the volume or the isospin of the projectile.Results: The IYR(m) shows a distribution of a linear part in the small-x fragments, and a nonlinear part in the large-x fragments. The linear part of IYR(m) is fitted. (1) In the calcium isotopic reactions, the IYR(m) depends on the isospin or the volume of the projectile, but δnp greatly influences the nonlinear part of the IYR(m). The IYR(m) does not depend on the colliding source in reactions of small bmax for the nonneutron-rich projectiles, and does not depend on the collision sources in reactions by the neutron-rich projectiles. (2) In reactions of the A=45 isobars, though IYR(m) depends on the isospin of projectile, IYR(m) shows small dependence on isospin if δnp>0. (3) In the reactions of projectiles

  14. All-optical analog comparator

    PubMed Central

    Li, Pu; Yi, Xiaogang; Liu, Xianglian; Zhao, Dongliang; Zhao, Yongpeng; Wang, Yuncai

    2016-01-01

    An analog comparator is one of the core units in all-optical analog-to-digital conversion (AO-ADC) systems, which digitizes different amplitude levels into two levels of logical ‘1’ or ‘0’ by comparing with a defined decision threshold. Although various outstanding photonic ADC approaches have been reported, almost all of them necessitate an electrical comparator to carry out this binarization. The use of an electrical comparator is in contradiction to the aim of developing all-optical devices. In this work, we propose a new concept of an all-optical analog comparator and numerically demonstrate an implementation based on a quarter-wavelength-shifted distributed feedback laser diode (QWS DFB-LD) with multiple quantum well (MQW) structures. Our results show that the all-optical comparator is very well suited for true AO-ADCs, enabling the whole digital conversion from an analog optical signal (continuous-time signal or discrete pulse signal) to a binary representation totally in the optical domain. In particular, this all-optical analog comparator possesses a low threshold power (several mW), high extinction ratio (up to 40 dB), fast operation rate (of the order of tens of Gb/s) and a step-like transfer function. PMID:27550874

  15. Biomimetic Analogs for Collagen Biomineralization

    PubMed Central

    Gu, L.; Kim, Y.K.; Liu, Y.; Ryou, H.; Wimmer, C.E.; Dai, L.; Arola, D.D.; Looney, S.W.; Pashley, D.H.; Tay, F.R.

    2011-01-01

    Inability of chemical phosphorylation of sodium trimetaphosphate to induce intrafibrillar mineralization of type I collagen may be due to the failure to incorporate a biomimetic analog to stabilize amorphous calcium phosphates (ACP) as nanoprecursors. This study investigated adsorption/desorption characteristics of hydrolyzed and pH-adjusted sodium trimetaphosphate (HPA-Na3P3O9) to collagen. Based on those results, a 5-minute treatment time with 2.8 wt% HPA-Na3P3O9 was used in a single-layer reconstituted collagen model to confirm that both the ACP-stabilization analog and matrix phosphoprotein analog must be present for intrafibrillar mineralization. The results of that model were further validated by complete remineralization of phosphoric-acid-etched dentin treated with the matrix phosphoprotein analog and lined with a remineralizing lining composite, and with the ACP-stabilization analog supplied in simulated body fluid. An understanding of the basic processes involved in intrafibrillar mineralization of reconstituted collagen fibrils facilitates the design of novel tissue engineering materials for hard tissue repair and regeneration. PMID:20940362

  16. All-optical analog comparator.

    PubMed

    Li, Pu; Yi, Xiaogang; Liu, Xianglian; Zhao, Dongliang; Zhao, Yongpeng; Wang, Yuncai

    2016-08-23

    An analog comparator is one of the core units in all-optical analog-to-digital conversion (AO-ADC) systems, which digitizes different amplitude levels into two levels of logical '1' or '0' by comparing with a defined decision threshold. Although various outstanding photonic ADC approaches have been reported, almost all of them necessitate an electrical comparator to carry out this binarization. The use of an electrical comparator is in contradiction to the aim of developing all-optical devices. In this work, we propose a new concept of an all-optical analog comparator and numerically demonstrate an implementation based on a quarter-wavelength-shifted distributed feedback laser diode (QWS DFB-LD) with multiple quantum well (MQW) structures. Our results show that the all-optical comparator is very well suited for true AO-ADCs, enabling the whole digital conversion from an analog optical signal (continuous-time signal or discrete pulse signal) to a binary representation totally in the optical domain. In particular, this all-optical analog comparator possesses a low threshold power (several mW), high extinction ratio (up to 40 dB), fast operation rate (of the order of tens of Gb/s) and a step-like transfer function.

  17. All-optical analog comparator

    NASA Astrophysics Data System (ADS)

    Li, Pu; Yi, Xiaogang; Liu, Xianglian; Zhao, Dongliang; Zhao, Yongpeng; Wang, Yuncai

    2016-08-01

    An analog comparator is one of the core units in all-optical analog-to-digital conversion (AO-ADC) systems, which digitizes different amplitude levels into two levels of logical ‘1’ or ‘0’ by comparing with a defined decision threshold. Although various outstanding photonic ADC approaches have been reported, almost all of them necessitate an electrical comparator to carry out this binarization. The use of an electrical comparator is in contradiction to the aim of developing all-optical devices. In this work, we propose a new concept of an all-optical analog comparator and numerically demonstrate an implementation based on a quarter-wavelength-shifted distributed feedback laser diode (QWS DFB-LD) with multiple quantum well (MQW) structures. Our results show that the all-optical comparator is very well suited for true AO-ADCs, enabling the whole digital conversion from an analog optical signal (continuous-time signal or discrete pulse signal) to a binary representation totally in the optical domain. In particular, this all-optical analog comparator possesses a low threshold power (several mW), high extinction ratio (up to 40 dB), fast operation rate (of the order of tens of Gb/s) and a step-like transfer function.

  18. Analogies in Science and Science Teaching

    ERIC Educational Resources Information Center

    Brown, Simon; Salter, Susan

    2010-01-01

    Analogies are often used in science, but students may not appreciate their significance, and so the analogies can be misunderstood or discounted. For this reason, educationalists often express concern about the use of analogies in teaching. Given the important place of analogies in the discourse of science, it is necessary that students are…

  19. Analogies in Science and Science Teaching

    ERIC Educational Resources Information Center

    Brown, Simon; Salter, Susan

    2010-01-01

    Analogies are often used in science, but students may not appreciate their significance, and so the analogies can be misunderstood or discounted. For this reason, educationalists often express concern about the use of analogies in teaching. Given the important place of analogies in the discourse of science, it is necessary that students are…

  20. Teaching Scientific Analogies: A Proposed Model.

    ERIC Educational Resources Information Center

    Zeitoun, Hassan Hussein

    Cognitive psychologists have recently alluded to the role analogies might play in learning unfamiliar topics. However, since the use of analogies in science teaching has not been adequately addressed, analogies mean different things to different people. Therefore, a model for the teaching of scientific analogies is proposed. A theoretical…

  1. Double Crater

    NASA Image and Video Library

    2012-03-23

    A double crater, called a crater doublet, is seen in the bottom right part of this image from NASA Dawn spacecraft of asteroid Vesta. This crater doublet was likely formed by the simultaneous impact of two fragments of a split projectile.

  2. Natural analogs for Yucca Mountain

    SciTech Connect

    Murphy, W.M.

    1995-11-01

    High-level radioactive waste in the US, spent fuels from commercial reactors and nuclear materials generated by defense activities, will remain potentially hazardous for thousands of years. Demonstrable long-term stability of certain geologic and geochemical systems motivates and sustains the concept that high-level waste can be safely isolated in geologic repositories for requisite periods of time. Each geologic repository is unique in its properties and performance with reguard to isolation of nuclear wastes. Studies of processes analogous to waste-form alteration and radioelement transport in environments analogous to Yucca Mountain are being conducted at two sites, described in this article to illustrate uses of natural analog data: the Nopal I uranium deposit in the Sierra Pena Blanca, Mexico, and the Akrotiri archaeological site on the island of Santorini, Greece.

  3. Analog enhancement of radiographic images

    NASA Technical Reports Server (NTRS)

    Baily, N. A.; Nachazel, R. J.

    1976-01-01

    The paper shows how analog methods for edge sharpening, contrast enhancement, and expansion of the range of gray levels of particular interest are effective for easy on-line application to video viewing of X-ray roentgenograms or to fluoroscopy. The technique for analog enhancement of radiographic images is a modified version of the system designed by Fuchs et al. (1972), whereby an all directional second derivative signal called detail signal is used to produce both vertical and horizontal enhancement of the image. Particular attention is given to noise filtration and contrast enhancement. Numerous radiographs supplement the text.

  4. Analog circuits for relaxation networks.

    PubMed

    Card, H

    1993-12-01

    Selected examples are presented of recent advances, primarily from the U.S. and Canada, in analog circuits for relaxation networks. Relaxation networks having feedback connections exhibit potentially greater computational power per neuron than feedforward networks. They are also more poorly understood especially with respect to learning algorithms. Examples are described of analog circuits for (i) supervised learning in deterministic Boltzmann machines, (ii) unsupervised competitive learning and feature maps and (iii) networks with resistive grids for vision and audition tasks. We also discuss recent progress on in-circuit learning and synaptic weight storage mechanisms.

  5. Metabolomic Discovery of Novel Urinary Galabiosylceramide Analogs as Fabry Disease Biomarkers

    NASA Astrophysics Data System (ADS)

    Boutin, Michel; Auray-Blais, Christiane

    2015-03-01

    Fabry disease is an X-linked, complex, multisystemic lysosomal storage disorder presenting marked phenotypic and genotypic variability among affected male and female patients. Glycosphingolipids, mainly globotriaosylceramide (Gb3) isoforms/analogs, globotriaosylsphingosine (lyso-Gb3) and analogs, as well as galabiosylceramide (Ga2) isoforms/analogs accumulate in the vascular endothelium, nerves, cardiomyocytes, renal glomerular and tubular epithelial cells, and biological fluids. The search for biomarkers reflecting disease severity and progression is still on-going. A metabolomic study using quadrupole time-of-flight mass spectrometry has revealed 22 galabiosylceramide isoforms/analogs in urine of untreated Fabry patients classified in seven groups according to their chemical structure: (1) Saturated fatty acid; (2) one extra double bond; (3) two extra double bonds; (4) hydroxylated saturated fatty acid; (5) hydroxylated fatty acid and one extra double bond; (6) hydrated sphingosine and hydroxylated fatty acid; (7) methylated amide linkage. Relative quantification of both Ga2 and Gb3 isoforms/analogs was performed. All these biomarkers are significantly more abundant in urine samples from untreated Fabry males compared with healthy male controls. A significant amount of Ga2 isoforms/analogs, accounting for 18% of all glycosphingolipids analyzed (Ga2 + Gb3 and respective isoforms/analogs), were present in urine of Fabry patients. Gb3 isoforms containing saturated fatty acids are the most abundant (60.9%) compared with 26.3% for Ga2. A comparison between Ga2 isoforms/analogs and their Gb3 counterparts also showed that the proportion of analogs with hydroxylated fatty acids is significantly greater for Ga2 (35.8%) compared with Gb3 (1.9%). These results suggest different biological pathways involved in the synthesis and/or degradation of Gb3 and Ga2 metabolites.

  6. Terrestrial analogs for space exploration habitation systems

    NASA Technical Reports Server (NTRS)

    Campbell, Paul D.; Brown, Jeri W.

    1992-01-01

    The Space Exploration Initiative (SEI) can use early earth-based analogs to simulate many aspects of space flight missions and system operation. These analogs can thus provide information supporting future missions to the moon and to Mars. A study was performed to investigate the potential of terrestrial analogs in simulating human space exploration missions. The study resulted in preliminary requirements and concepts for analog habitation systems, and further study in this area is necessary for SEI terrestrial analog development.

  7. Quantitative Analysis of Single Amino Acid Variant Peptides Associated with Pancreatic Cancer in Serum by an Isobaric Labeling Quantitative Method

    PubMed Central

    2015-01-01

    Single amino acid variations are highly associated with many human diseases. The direct detection of peptides containing single amino acid variants (SAAVs) derived from nonsynonymous single nucleotide polymorphisms (SNPs) in serum can provide unique opportunities for SAAV associated biomarker discovery. In the present study, an isobaric labeling quantitative strategy was applied to identify and quantify variant peptides in serum samples of pancreatic cancer patients and other benign controls. The largest number of SAAV peptides to date in serum including 96 unique variant peptides were quantified in this quantitative analysis, of which five variant peptides showed a statistically significant difference between pancreatic cancer and other controls (p-value < 0.05). Significant differences in the variant peptide SDNCEDTPEAGYFAVAVVK from serotransferrin were detected between pancreatic cancer and controls, which was further validated by selected reaction monitoring (SRM) analysis. The novel biomarker panel obtained by combining α-1-antichymotrypsin (AACT), Thrombospondin-1 (THBS1) and this variant peptide showed an excellent diagnostic performance in discriminating pancreatic cancer from healthy controls (AUC = 0.98) and chronic pancreatitis (AUC = 0.90). These results suggest that large-scale analysis of SAAV peptides in serum may provide a new direction for biomarker discovery research. PMID:25393578

  8. Precision mass measurements of magnesium isotopes and implications for the validity of the isobaric mass multiplet equation

    NASA Astrophysics Data System (ADS)

    Brodeur, M.; Kwiatkowski, A. A.; Drozdowski, O. M.; Andreoiu, C.; Burdette, D.; Chaudhuri, A.; Chowdhury, U.; Gallant, A. T.; Grossheim, A.; Gwinner, G.; Heggen, H.; Holt, J. D.; Klawitter, R.; Lassen, J.; Leach, K. G.; Lennarz, A.; Nicoloff, C.; Raeder, S.; Schultz, B. E.; Stroberg, S. R.; Teigelhöfer, A.; Thompson, R.; Wieser, M.; Dilling, J.

    2017-09-01

    If the mass excess of neutron-deficient nuclei and their neutron-rich mirror partners are both known, it can be shown that deviations of the isobaric mass multiplet equation (IMME) in the form of a cubic term can be probed. Such a cubic term was probed by using the atomic mass of neutron-rich magnesium isotopes measured using the TITAN Penning trap and the recently measured proton-separation energies of 29Cl and 30Ar. The atomic mass of 27Mg was found to be within 1.6 σ of the value stated in the Atomic Mass Evaluation. The atomic masses of Mg,2928 were measured to be both within 1 σ , while being 7 and 33 times more precise, respectively. Using the 29Mg mass excess and previous measurements of 29Cl, we uncovered a cubic coefficient of d =28 (7 )keV , which is the largest known cubic coefficient of the IMME. This departure, however, could also be caused by experimental data with unknown systematic errors. Hence there is a need to confirm the mass excess of 28S and the one-neutron separation energy of 29Cl, which have both come from a single measurement. Finally, our results were compared with ab initio calculations from the valence-space in-medium similarity renormalization group, resulting in a good agreement.

  9. Isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomic analysis of Cryptococcus humicola response to aluminum stress.

    PubMed

    Zhang, Jingjing; Zhang, Lei; Qiu, Jinkui; Nian, Hongjuan

    2015-10-01

    Cryptococcus humicola is a highly aluminum (Al) tolerant yeast strain isolated from a tea field. Here the relative changes of protein expression in C. humicola undergoing aluminum stress were analyzed to understand the genetic basis of aluminum tolerance. In this work, iTRAQ-based (isobaric tags for relative and absolute quantification) quantitative proteomic technology was used to detect statistically significant proteins associated with the response to aluminum stress. A total of 625 proteins were identified and were mainly involved in translation/ribosomal structure and biogenesis, posttranslational modification/protein turnover/chaperones, energy production and conversion, and amino acid transport and metabolism. Of these proteins, 59 exhibited differential expression during aluminum stress. Twenty-nine proteins up-regulated by aluminum were mainly involved in translation/ribosomal structure and biogenesis, posttranslational modification/protein turnover and chaperones, and lipid transport and metabolism. Thirty proteins down-regulated by aluminum were mainly associated with energy transport and metabolism, translation/ribosomal structure and biogenesis, posttranslational modification/protein turnover/chaperones, and lipid transport and metabolism. The potential functions of some proteins in aluminum tolerance are discussed. These functional changes may be beneficial for cells to protect themselves from aluminum toxic conditions. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

  10. Proteomic Quantification and Site-Mapping of S-Nitrosylated Proteins Using Isobaric iodoTMT Reagents

    PubMed Central

    2015-01-01

    S-Nitrosylation is a redox-based protein post-translational modification in response to nitric oxide signaling and is involved in a wide range of biological processes. Detection and quantification of protein S-nitrosylation have been challenging tasks due to instability and low abundance of the modification. Many studies have used mass spectrometry (MS)-based methods with different thiol-reactive reagents to label and identify proteins with S-nitrosylated cysteine (SNO-Cys). In this study, we developed a novel iodoTMT switch assay (ISA) using an isobaric set of thiol-reactive iodoTMTsixplex reagents to specifically detect and quantify protein S-nitrosylation. Irreversible labeling of SNO-Cys with the iodoTMTsixplex reagents enables immune-affinity detection of S-nitrosylated proteins, enrichment of iodoTMT-labeled peptides by anti-TMT resin, and importantly, unambiguous modification site-mapping and multiplex quantification by liquid chromatography–tandem MS. Additionally, we significantly improved anti-TMT peptide enrichment efficiency by competitive elution. Using ISA, we identified a set of SNO-Cys sites responding to lipopolysaccharide (LPS) stimulation in murine BV-2 microglial cells and revealed effects of S-allyl cysteine from garlic on LPS-induced protein S-nitrosylation in antioxidative signaling and mitochondrial metabolic pathways. ISA proved to be an effective proteomic approach for quantitative analysis of S-nitrosylation in complex samples and will facilitate the elucidation of molecular mechanisms of nitrosative stress in disease. PMID:24926564

  11. Extracting survival parameters from isothermal, isobaric, and "iso-concentration" inactivation experiments by the "3 end points method".

    PubMed

    Corradini, M G; Normand, M D; Newcomer, C; Schaffner, D W; Peleg, M

    2009-01-01

    Theoretically, if an organism's resistance can be characterized by 3 survival parameters, they can be found by solving 3 simultaneous equations that relate the final survival ratio to the lethal agent's intensity. (For 2 resistance parameters, 2 equations will suffice.) In practice, the inevitable experimental scatter would distort the results of such a calculation or render the method unworkable. Averaging the results obtained with more than 3 final survival ratio triplet combinations, determined in four or more treatments, can remove this impediment. This can be confirmed by the ability of a kinetic inactivation model derived from the averaged parameters to predict survival patterns under conditions not employed in their determination, as demonstrated with published isothermal survival data of Clostridium botulinum spores, isobaric data of Escherichia coli under HPP, and Pseudomonas exposed to hydrogen peroxide. Both the method and the underlying assumption that the inactivation followed a Weibull-Log logistic (WeLL) kinetics were confirmed in this way, indicating that when an appropriate survival model is available, it is possible to predict the entire inactivation curves from several experimental final survival ratios alone. Where applicable, the method could simplify the experimental procedure and lower the cost of microbial resistance determinations. In principle, the methodology can be extended to deteriorative chemical reactions if they too can be characterized by 2 or 3 kinetic parameters.

  12. Spectroscopy of {sup 20}Mg: The isobaric mass multiplet equation for the 2{sup +} states of the A=20, T=2 quintet and distant mirror nuclei

    SciTech Connect

    Gade, A.; Bowen, M. D.; Brown, B. A.; Campbell, C. M.; Cook, J. M.; Glasmacher, T.; McDaniel, S.; Siwek, K.; Adrich, P.; Bazin, D.; Obertelli, A.; Weisshaar, D.; Hosier, K.; McGlinchery, D.; Riley, L. A.

    2007-08-15

    We report on the first determination of the 2{sub 1}{sup +} energy of {sup 20}Mg, the most neutron-deficient Mg isotope known to exist. The result, E(2{sub 1}{sup +})=1598(10) keV, obtained from in-beam {gamma}-ray spectroscopy following the two-neutron removal from a {sup 22}Mg secondary beam, is discussed in the framework of the isobaric mass multiplet equation (IMME). Resulting predictions for the excitation energies of the T=2,2{sup +} states in the {sup 20}F and {sup 20}Na isobars are presented. The mirror energy difference, E(2{sub 1}{sup +},{sup 20}Mg)-E(2{sub 1}{sup +},{sup 20}O)=-77(10) keV, is compared to a recent prediction within the nuclear shell model based on the 'USD'm - gap Z14<'' modification of the universal sd (USD) effective interaction.

  13. Revalidation of the isobaric multiplet mass equation for the A=20 quintet

    SciTech Connect

    Glassman, B. E.; Pérez-Loureiro, D.; Wrede, C.; Allen, J.; Bardayan, D. W.; Bennett, M. B.; Brown, B. A.; Chipps, K. A.; Febbraro, M.; Fry, C.; Hall, M. R.; Hall, O.; Liddick, S. N.; O'Malley, P.; Ong, W.; Pain, S. D.; Schwartz, S. B.; Shidling, P.; Sims, H.; Thompson, P.; Zhang, H.

    2015-10-29

    An unexpected breakdown of the isobaric multiplet mass equation in the A = 20, T = 2 quintet was recently reported, presenting a challenge to modern theories of nuclear structure. In the present work, the excitation energy of the lowest T = 2 state in Na-20 has been measured to be 6498.4 +/- 0.2stat ± 0.4syst keV by using the superallowed 0+ → 0+ beta decay of Mg-20 to access it and an array of high-purity germanium detectors to detect its gamma-ray deexcitation. This value differs by 27 keV (1.9 standard deviations) from the recommended value of 6525 ± 14 keV and is a factor of 28 more precise. The isobaric multiplet mass equation is shown to be revalidated when the new value is adopted.

  14. Analogies and "Modeling Analogies" in Teaching: Some Examples in Basic Electricity.

    ERIC Educational Resources Information Center

    Dupin, J. J.; Johsua, S.

    1989-01-01

    Investigates the effect of modeling analogy on learning of the concepts of electricity in grade 6, 8, and 10. Describes 2 analogies (train analogy and thermal analogy) with diagrams and examples. Discusses the accessibility, transferability, and difficulty of each analogy. Reports treatment effect and some further implications. (YP)

  15. Double Layers in Astrophysics

    NASA Technical Reports Server (NTRS)

    Williams, Alton C. (Editor); Moorehead, Tauna W. (Editor)

    1987-01-01

    Topics addressed include: laboratory double layers; ion-acoustic double layers; pumping potential wells; ion phase-space vortices; weak double layers; electric fields and double layers in plasmas; auroral double layers; double layer formation in a plasma; beamed emission from gamma-ray burst source; double layers and extragalactic jets; and electric potential between plasma sheet clouds.

  16. High-sensitivity isobar-free AMS measurements and reference materials for 55Fe, 68Ge and 202gPb

    NASA Astrophysics Data System (ADS)

    Wallner, A.; Bichler, M.; Buczak, K.; Fink, D.; Forstner, O.; Golser, R.; Hotchkis, M. A. C.; Klix, A.; Krasa, A.; Kutschera, W.; Lederer, C.; Plompen, A.; Priller, A.; Schumann, D.; Semkova, V.; Steier, P.

    2013-01-01

    Isobaric interference represents one of the major limitations in mass spectrometry. For a few cases in AMS with tandem accelerators, isobaric interference is completely excluded like the well-known major isotopes 14C, 26Al, 129I. Additional isotopes are 55Fe (t1/2 = 2.74 years), 68Ge (t1/2 = 270.9 days) and 202Pb (t1/2 = 52.5 kyr), with 68Ge and 202Pb never been used in AMS so far. Their respective stable isobars, 55Mn, 68Zn and 202Hg do not form stable negative ions. The exceptional sensitivity of AMS for 55Fe, 68Ge and 202gPb offers important insights into such different fields like nuclear astrophysics, fundamental nuclear physics and technological applications. VERA, a dedicated AMS facility is well suited for developing procedures for new and non-standard isotopes. AMS measurements at the VERA facility established low backgrounds for these radionuclides in natural samples. Limits for isotope ratios of <10-15, <10-16 and ⩽2 × 10-14 were measured for 55Fe/56Fe, 68Ge/70Ge and 202Pb/Pb, respectively. In order to generate accurate isotope ratios of sample materials, AMS relies on the parallel measurement of reference materials with well-known ratios. A new and highly accurate reference material for 55Fe measurements with an uncertainty of ±1.6% was produced from a certified reference solution. In case of 68Ge dedicated neutron activations produced a sufficiently large number of 68Ge atoms that allowed quantifying them through the activity of its decay product 68Ga. Finally, for 202Pb, the short-lived isobar 202Tl was produced via neutron activation and served as a proxy for 202Pb AMS measurements.

  17. Effect of isobaric breathing gas shifts from air to heliox mixtures on resolution of air bubbles in lipid and aqueous tissues of recompressed rats.

    PubMed

    Hyldegaard, O; Kerem, D; Melamed, Y

    2011-09-01

    Deep tissue isobaric counterdiffusion that may cause unwanted bubble formation or transient bubble growth has been referred to in theoretical models and demonstrated by intravascular gas formation in animals, when changing inert breathing gas from nitrogen to helium after hyperbaric air breathing. We visually followed the in vivo resolution of extravascular air bubbles injected at 101 kPa into nitrogen supersaturated rat tissues: adipose, spinal white matter, skeletal muscle or tail tendon. Bubbles were observed during isobaric breathing-gas shifts from air to normoxic (80:20) heliox mixture while at 285 kPa or following immediate recompression to either 285 or 405 kPa, breathing 80:20 and 50:50 heliox mixtures. During the isobaric shifts, some bubbles in adipose tissue grew marginally for 10-30 min, subsequently they shrank and disappeared at a rate similar to or faster than during air breathing. No such bubble growth was observed in spinal white matter, skeletal muscle or tendon. In spinal white matter, an immediate breathing gas shift after the hyperbaric air exposure from air to both (80:20) and (50:50) heliox, coincident with recompression to either 285 or 405 kPa, caused consistent shrinkage of all air bubbles, until they disappeared from view. Deep tissue isobaric counterdiffusion may cause some air bubbles to grow transiently in adipose tissue. The effect is marginal and of no clinical consequence. Bubble disappearance rate is faster with heliox breathing mixtures as compared to air. We see no reason for reservations in the use of heliox breathing during treatment of air-diving-induced decompression sickness.

  18. Improving data quality and preserving HCD-generated reporter ions with EThcD for isobaric tag-based quantitative proteomics and proteome-wide PTM studies.

    PubMed

    Yu, Qing; Shi, Xudong; Feng, Yu; Kent, K Craig; Li, Lingjun

    2017-05-22

    Mass spectrometry (MS)-based isobaric labeling has undergone rapid development in recent years due to its capability for high throughput quantitation. Apart from its originally designed use with collision-induced dissociation (CID) and higher-energy collisional dissociation (HCD), isobaric tagging technique could also work with electron-transfer dissociation (ETD), which provides complementarity to CID and is preferred in sequencing peptides with post-translational modifications (PTMs). However, ETD suffers from long reaction time, reduced duty cycle and bias against peptides with lower charge states. In addition, common fragmentation mechanism in ETD results in altered reporter ion production, decreased multiplexing capability, and even loss of quantitation capability for some of the isobaric tags, including custom-designed dimethyl leucine (DiLeu) tags. Here, we demonstrate a novel electron-transfer/higher-energy collision dissociation (EThcD) approach that preserves original reporter ion channels, mitigates bias against lower charge states, improves sensitivity, and significantly improves data quality for quantitative proteomics and proteome-wide PTM studies. Systematic optimization was performed to achieve a balance between data quality and sensitivity. We provide direct comparison of EThcD with ETD and HCD for DiLeu- and TMT-labeled HEK cell lysate and IMAC enriched phosphopeptides. Results demonstrate improved data quality and phosphorylation localization accuracy while preserving sufficient reporter ion production. Biological studies were performed to investigate phosphorylation changes in a mouse vascular smooth muscle cell line treated with four different conditions. Overall, EThcD exhibits superior performance compared to conventional ETD and offers distinct advantages compared to HCD in isobaric labeling based quantitative proteomics and quantitative PTM studies. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Algicidal Activity of Stilbene Analogs

    USDA-ARS?s Scientific Manuscript database

    As part of our continuing search for natural product and natural product-based compounds for the control of off-flavor in catfish, a total of twenty nine stilbene analogs were synthesized and evaluated for algicidal activity against the 2-methylisoborneol (MIB)-producing cyanobacterium Oscillatoria ...

  20. Paper Analogies Enhance Biology Teaching.

    ERIC Educational Resources Information Center

    Stencel, John E.

    1997-01-01

    Describes how to use paper analogies as models to illustrate various concepts in biology, human anatomy, and physiology classes. Models include biochemical paper models, protein papergrams, a paper model of early brain development, and a 3-D paper model of a eukaryotic cell. (AIM)

  1. Understanding & Teaching Genetics Using Analogies

    ERIC Educational Resources Information Center

    Woody, Scott; Himelblau, Ed

    2013-01-01

    We present a collection of analogies that are intended to help students better understand the foreign and often nuanced vocabulary of the genetics curriculum. Why is it called the "wild type"? What is the difference between a locus, a gene, and an allele? What is the functional (versus a rule-based) distinction between dominant and…

  2. Electrical analog to projectile motion

    NASA Astrophysics Data System (ADS)

    Vondracek, Mark

    1998-04-01

    This article describes an electrical analog to traditional projectile problems given in high school and introductory college classes. It also discusses the importance of stressing the understanding of physical laws and principles to students, and that the physics behind a problem is more important than being able to memorize and use various equations.

  3. Analog Input Data Acquisition Software

    NASA Technical Reports Server (NTRS)

    Arens, Ellen

    2009-01-01

    DAQ Master Software allows users to easily set up a system to monitor up to five analog input channels and save the data after acquisition. This program was written in LabVIEW 8.0, and requires the LabVIEW runtime engine 8.0 to run the executable.

  4. Analogy of the Cell Project

    ERIC Educational Resources Information Center

    Science Scope, 2005

    2005-01-01

    In this project, students compare the makeup of a cell to an everyday working unit or system. They create a three-dimensional object that represents their analogy. For example, students could create a car motor or manufacturing plant. (Of course, this is totally hand-created by them, so it can be a homemade re-creation of a system, not an actual…

  5. Analogy of the Cell Project

    ERIC Educational Resources Information Center

    Science Scope, 2005

    2005-01-01

    In this project, students compare the makeup of a cell to an everyday working unit or system. They create a three-dimensional object that represents their analogy. For example, students could create a car motor or manufacturing plant. (Of course, this is totally hand-created by them, so it can be a homemade re-creation of a system, not an actual…

  6. Analog Simulation of a Laser.

    ERIC Educational Resources Information Center

    Kessler, Gary

    1982-01-01

    Presents an analog simulation of laser properties (finding time evolution of the intensity of a ruby laser pulse) which serves as the basis of a three-four hour laboratory experiment. Includes programs for solution to rate equations of a three-level laser and production of a giant pulse in a ruby laser. (Author/SK)

  7. Bayesian Analogy with Relational Transformations

    ERIC Educational Resources Information Center

    Lu, Hongjing; Chen, Dawn; Holyoak, Keith J.

    2012-01-01

    How can humans acquire relational representations that enable analogical inference and other forms of high-level reasoning? Using comparative relations as a model domain, we explore the possibility that bottom-up learning mechanisms applied to objects coded as feature vectors can yield representations of relations sufficient to solve analogy…

  8. Geometrical Analogies in Mathematics Lessons

    ERIC Educational Resources Information Center

    Eid, Wolfram

    2007-01-01

    A typical form of thinking to approach problem solutions humanly is thinking in analogous structures. Therefore school, especially mathematical lessons should help to form and to develop corresponding heuristic abilities of the pupils. In the contribution, a summary of possibilities of mathematics lessons regarding this shall particularly be…

  9. Mathematical Analogy and Metaphorical Insight

    ERIC Educational Resources Information Center

    Zwicky, Jan

    2010-01-01

    How are we to understand the power of certain literary metaphors? The author argues that the apprehension of good metaphors is importantly similar to the apprehension of fruitful mathematical analogies: both involve a structural realignment of vision. The author then explores consequences of this claim, drawing conceptually significant parallels…

  10. Analogy between Thermodynamics and Mechanics.

    ERIC Educational Resources Information Center

    Peterson, Mark A.

    1979-01-01

    Establishes and illustrates a formal analogy between the motion of a particle and the "motion" of the equilibrium state of a homogeneous system in a quasistatic process. The purpose is to show that there is a much larger set of natural coordinate transformations in thermodynamics. (GA)

  11. Understanding & Teaching Genetics Using Analogies

    ERIC Educational Resources Information Center

    Woody, Scott; Himelblau, Ed

    2013-01-01

    We present a collection of analogies that are intended to help students better understand the foreign and often nuanced vocabulary of the genetics curriculum. Why is it called the "wild type"? What is the difference between a locus, a gene, and an allele? What is the functional (versus a rule-based) distinction between dominant and…

  12. Analog Simulation of a Laser.

    ERIC Educational Resources Information Center

    Kessler, Gary

    1982-01-01

    Presents an analog simulation of laser properties (finding time evolution of the intensity of a ruby laser pulse) which serves as the basis of a three-four hour laboratory experiment. Includes programs for solution to rate equations of a three-level laser and production of a giant pulse in a ruby laser. (Author/SK)

  13. Schema Training in Analogical Reasoning.

    ERIC Educational Resources Information Center

    Robins, Shani; Mayer, Richard E.

    1993-01-01

    In 3 experiments, 93, 97, and 86 college students, respectively, learned how to solve 20 verbal analogy problems and took transfer and memory tests. Results are inconsistent with active responding theory and further indicate that schema induction is maximized when the schemas are made salient and the cognitive system is not overloaded. (SLD)

  14. Processes in Verbal Analogy Solution.

    ERIC Educational Resources Information Center

    Grudin, Jonathan

    1980-01-01

    Verbal analogy solution is more flexible than is suggested by either the standard process theory or Sternberg's theory. It was determined that subjects initially examine terms A and B; if this strategy is not successful, they examine the relationship between A and C. (Author/CP)

  15. Bayesian Analogy with Relational Transformations

    ERIC Educational Resources Information Center

    Lu, Hongjing; Chen, Dawn; Holyoak, Keith J.

    2012-01-01

    How can humans acquire relational representations that enable analogical inference and other forms of high-level reasoning? Using comparative relations as a model domain, we explore the possibility that bottom-up learning mechanisms applied to objects coded as feature vectors can yield representations of relations sufficient to solve analogy…

  16. International Alligator Rivers Analog Project

    SciTech Connect

    Bichard, G.F.

    1988-01-01

    The Australian Nuclear Science and Technology Organization (ANSTO), the Japan Atomic Energy Research Institute, the Swedish Nuclear Power Inspectorate, the U.K. Department of the Environment, the US Nuclear Regulatory Commission (NRC), and the Power Reactor and Nuclear Fuel Development Corporation of Japan are participating under the aegis of the Nuclear Energy Agency in the International Alligator Rivers Analog Project. The project has a duration of 3 yr, starting in 1988. The project has grown out of a research program on uranium ore bodies as analogs of high-level waste (HLW) repositories undertaken by ANSTO supported by the NRC. A primary objective of the project is to develop an approach to radionuclide transport model validation that may be used by the participants to support assessments of the safety of radioactive waste repositories. The approach involves integrating mathematical and physical modeling with hydrological and geochemical field and laboratory investigations of the analog site. The Koongarra uranium ore body has been chosen as the analog site because it has a secondary ore body that has formed over the past million years as a result of leaching by groundwater flowing through fractures in the primary ore body.

  17. Schema Training in Analogical Reasoning.

    ERIC Educational Resources Information Center

    Robins, Shani; Mayer, Richard E.

    1993-01-01

    In 3 experiments, 93, 97, and 86 college students, respectively, learned how to solve 20 verbal analogy problems and took transfer and memory tests. Results are inconsistent with active responding theory and further indicate that schema induction is maximized when the schemas are made salient and the cognitive system is not overloaded. (SLD)

  18. Mathematical Analogy and Metaphorical Insight

    ERIC Educational Resources Information Center

    Zwicky, Jan

    2010-01-01

    How are we to understand the power of certain literary metaphors? The author argues that the apprehension of good metaphors is importantly similar to the apprehension of fruitful mathematical analogies: both involve a structural realignment of vision. The author then explores consequences of this claim, drawing conceptually significant parallels…

  19. Double screening

    SciTech Connect

    Gratia, Pierre; Hu, Wayne; Joyce, Austin; Ribeiro, Raquel H.

    2016-06-15

    Attempts to modify gravity in the infrared typically require a screening mechanism to ensure consistency with local tests of gravity. These screening mechanisms fit into three broad classes; we investigate theories which are capable of exhibiting more than one type of screening. Specifically, we focus on a simple model which exhibits both Vainshtein and kinetic screening. We point out that due to the two characteristic length scales in the problem, the type of screening that dominates depends on the mass of the sourcing object, allowing for different phenomenology at different scales. We consider embedding this double screening phenomenology in a broader cosmological scenario and show that the simplest examples that exhibit double screening are radiatively stable.

  20. NMR Structural Studies of Antimicrobial Peptides: LPcin Analogs

    PubMed Central

    Jeong, Ji-Ho; Kim, Ji-Sun; Choi, Sung-Sub; Kim, Yongae

    2016-01-01

    Lactophoricin (LPcin), a component of proteose peptone (113–135) isolated from bovine milk, is a cationic amphipathic antimicrobial peptide consisting of 23 amino acids. We designed a series of N- or C-terminal truncated variants, mutated analogs, and truncated mutated analogs using peptide-engineering techniques. Then, we selected three LPcin analogs of LPcin-C8 (LPcin-YK1), LPcin-T2WT6W (LPcin-YK2), and LPcin-T2WT6W-C8 (LPcin-YK3), which may have better antimicrobial activities than LPcin, and successfully expressed them in E. coli with high yield. We elucidated the 3D structures and topologies of the three LPcin analogs in membrane environments by conducting NMR structural studies. We investigated the purity of the LPcin analogs and the α-helical secondary structures by performing 1H-15N 2D HSQC and HMQC-NOESY liquid-state NMR spectroscopy using protein-containing micelle samples. We measured the 3D structures and tilt angles in membranes by conducting 15N 1D and 2D 1H-15N SAMMY type solid-state NMR spectroscopy with an 800 MHz in-house-built 1H-15N double-resonance solid-state NMR probe with a strip-shield coil, using protein-containing large bicelle samples aligned and confirmed by molecular-dynamics simulations. The three LPcin analogs were found to be curved α-helical structures, with tilt angles of 55–75° for normal membrane bilayers, and their enhanced activities may be correlated with these topologies. PMID:26789765

  1. The significance of monoisotopic and carbon-13 isobars for the identification of a 19-component dodecapeptide library by positive ion electrospray Fourier transform ion cyclotron resonance mass spectrometry.

    PubMed

    Ramjit, H G; Kruppa, G H; Spier, J P; Ross, C W; Garsky, V M

    2000-01-01

    Harnessing the ultra high resolution capabilities of Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) and positive ion electrospray, we have demonstrated the significance and utility of cumulative mass defect high resolution mass separation stable isotope distribution, exact mass measurement and elemental formula as a means of simultaneously identifying 19 components of the dodecapeptide library Ac-ANKISYQS[X]STE-NH(2). With an instrument resolution of 275 000 (average), isobaric multiplets attributed to monoisotopic and carbon-13 components of peptides: Ac approximately SLS approximately NH(2); Ac approximately SNS approximately NH(2); Ac approximately SOS approximately NH(2); Ac approximately SDS approximately NH(2); within the mass window of 1380-1385 Da, and Ac approximately SQS approximately NH(2); Ac approximately SKS approximately NH(2); Ac approximately SES approximately NH(2); Ac approximately SMS approximately NH(2), within the mass window 1395-1400 Da, were mass resolved, accurately mass measured and identified from the computed molecular formulas. This experimental procedure enabled the separation of monoisotopic and carbon-13 isobars yielding enhanced selectivity and specificity and serves to illustrate the significance of monoisotopic and carbon-13 isobars in final product analysis. Chromatographic separation (HPLC) was of limited utility except for monitoring the overall extent of reaction and apparent product distribution. Positive ion electrospray-FTICR-MS and fast atom bombardment (FAB) MS were used to assess final product quality and apparent component distribution.

  2. Crows spontaneously exhibit analogical reasoning.

    PubMed

    Smirnova, Anna; Zorina, Zoya; Obozova, Tanya; Wasserman, Edward

    2015-01-19

    Analogical reasoning is vital to advanced cognition and behavioral adaptation. Many theorists deem analogical thinking to be uniquely human and to be foundational to categorization, creative problem solving, and scientific discovery. Comparative psychologists have long been interested in the species generality of analogical reasoning, but they initially found it difficult to obtain empirical support for such thinking in nonhuman animals (for pioneering efforts, see [2, 3]). Researchers have since mustered considerable evidence and argument that relational matching-to-sample (RMTS) effectively captures the essence of analogy, in which the relevant logical arguments are presented visually. In RMTS, choice of test pair BB would be correct if the sample pair were AA, whereas choice of test pair EF would be correct if the sample pair were CD. Critically, no items in the correct test pair physically match items in the sample pair, thus demanding that only relational sameness or differentness is available to support accurate choice responding. Initial evidence suggested that only humans and apes can successfully learn RMTS with pairs of sample and test items; however, monkeys have subsequently done so. Here, we report that crows too exhibit relational matching behavior. Even more importantly, crows spontaneously display relational responding without ever having been trained on RMTS; they had only been trained on identity matching-to-sample (IMTS). Such robust and uninstructed relational matching behavior represents the most convincing evidence yet of analogical reasoning in a nonprimate species, as apes alone have spontaneously exhibited RMTS behavior after only IMTS training. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Bayesian analogy with relational transformations.

    PubMed

    Lu, Hongjing; Chen, Dawn; Holyoak, Keith J

    2012-07-01

    How can humans acquire relational representations that enable analogical inference and other forms of high-level reasoning? Using comparative relations as a model domain, we explore the possibility that bottom-up learning mechanisms applied to objects coded as feature vectors can yield representations of relations sufficient to solve analogy problems. We introduce Bayesian analogy with relational transformations (BART) and apply the model to the task of learning first-order comparative relations (e.g., larger, smaller, fiercer, meeker) from a set of animal pairs. Inputs are coded by vectors of continuous-valued features, based either on human magnitude ratings, normed feature ratings (De Deyne et al., 2008), or outputs of the topics model (Griffiths, Steyvers, & Tenenbaum, 2007). Bootstrapping from empirical priors, the model is able to induce first-order relations represented as probabilistic weight distributions, even when given positive examples only. These learned representations allow classification of novel instantiations of the relations and yield a symbolic distance effect of the sort obtained with both humans and other primates. BART then transforms its learned weight distributions by importance-guided mapping, thereby placing distinct dimensions into correspondence. These transformed representations allow BART to reliably solve 4-term analogies (e.g., larger:smaller::fiercer:meeker), a type of reasoning that is arguably specific to humans. Our results provide a proof-of-concept that structured analogies can be solved with representations induced from unstructured feature vectors by mechanisms that operate in a largely bottom-up fashion. We discuss potential implications for algorithmic and neural models of relational thinking, as well as for the evolution of abstract thought. Copyright 2012 APA, all rights reserved.

  4. A CMOS field-programmable analog array

    NASA Astrophysics Data System (ADS)

    Lee, Edward K. F.; Gulak, P. G.

    1991-12-01

    The design details and test results of a field-programmable analog array (FPAA) prototype chip in 1.2-micron CMOS are presented. The analog array is based on subthreshold circuit techniques and consists of a collection of a homogeneous configurable analog blocks (CABs) and an interconnection network. Interconnections between CABs and the analog functions to be implemented in each block are defined by a set of configuration bits loaded serially into an onboard shift register by the user. Macromodels are developed for the analog functions in order to simulate various neural network applications on the field-programmable analog array.

  5. A comparison of the effects of preanesthetic administration of crystalloid versus colloid on intrathecal spread of isobaric spinal anesthetics and cerebrospinal fluid movement.

    PubMed

    Shin, Byung Seop; Kim, Chung Su; Sim, Woo Seok; Lee, Chul Joong; Kim, Sung Tae; Kim, Gunn Hee; Bang, Si Ra; Lee, Sang Hyun; Hyun, Sun Ji; Kim, Gaab Soo

    2011-04-01

    Movement of the cerebrospinal fluid (CSF) is one of the most important factors in determining the intrathecal spread of isobaric spinal anesthetics. Preanesthetic administration of either crystalloid or colloid immediately before spinal anesthesia (preload) may result in different CSF pulsatile movement because of their different physical properties. We examined whether preload of crystalloid versus colloid may have different effects on the intrathecal spread of isobaric spinal anesthetics as a result of their different CSF dynamics regarding its pulsatile movement. In a clinical study of isobaric spinal anesthesia, patients were allocated into 1 of 2 groups according to preload with either crystalloid (n = 30) or colloid (n = 30) before spinal anesthesia with 0.5 isobaric tetracaine. The pulsatile movements of CSF at the L2-3 intervertebral space and midportion of the aqueduct of Sylvius were also examined by magnetic resonance images in healthy volunteers (n = 23) at 0, 30, and 60 minutes after administering either crystalloid or colloid. In the clinical study, the time to reach the peak sensory block level was delayed significantly in the crystalloid preload group (27.2 ± 17.8 minutes; P < 0.01) compared with the colloid preload group (13.9 ± 7.0 minutes). The median sensory block levels of the crystalloid preload group at 15 minutes (T10, P < 0.05) and 20 minutes (T9.5, P < 0.05) were significantly lower than those (T8, T7, respectively) of the colloid preload group. In the magnetic resonance imaging study, cranially directed CSF pulsatile movement decreased significantly at the L2-3 intervertebral intrathecal space at 30 minutes after crystalloid administration, but not after colloid administration. The CSF production rate significantly increased at 30 minutes (637 μL/min, P < 0.05) after crystalloid preload compared with the baseline measurement (448 μL/min), and then slightly decreased (609 μL/min) at 60 minutes. In the colloid preload group, the CSF

  6. Light-front representation of chiral dynamics with Δ isobar and large-Nc relations

    SciTech Connect

    Granados, C.; Weiss, C.

    2016-06-13

    Transverse densities describe the spatial distribution of electromagnetic current in the nucleon at fixed light-front time. At peripheral distances b = O(Mπ–1) the densities are governed by chiral dynamics and can be calculated model-independently using chiral effective field theory (EFT). Recent work has shown that the EFT results can be represented in first-quantized form, as overlap integrals of chiral light-front wave functions describing the transition of the nucleon to soft-pion-nucleon intermediate states, resulting in a quantum-mechanical picture of the peripheral transverse densities. We now extend this representation to include intermediate states with Δ isobars and implement relations based on the large-Nc limit of QCD. We derive the wave function overlap formulas for the Δ contributions to the peripheral transverse densities by way of a three-dimensional reduction of relativistic chiral EFT expressions. Our procedure effectively maintains rotational invariance and avoids the ambiguities with higher-spin particles in the light-front time-ordered approach. We study the interplay of πN and πΔ intermediate states in the quantum-mechanical picture of the densities in a transversely polarized nucleon. We show that the correct Nc-scaling of the charge and magnetization densities emerges as the result of the particular combination of currents generated by intermediate states with degenerate N and Δ. The off-shell behavior of the chiral EFT is summarized in contact terms and can be studied easily. As a result, the methods developed here can be applied to other peripheral densities and to moments of the nucleon's generalized parton distributions.

  7. X-ray continuum as a measure of pressure and fuel-shell mix in compressed isobaric hydrogen implosion cores

    NASA Astrophysics Data System (ADS)

    Epstein, R.; Goncharov, V. N.; Marshall, F. J.; Betti, R.; Nora, R.; Christopherson, A. R.; Golovkin, I. E.; MacFarlane, J. J.

    2015-02-01

    Pressure, by definition, characterizes the conditions within an isobaric implosion core at peak compression [Gus'kov et al., Nucl. Fusion 16, 957 (1976); Betti et al., Phys. Plasmas 8, 5257 (2001)] and is a key parameter in quantifying its near-ignition performance [Lawson, Proc. Phys. Soc. London, B 70, 6 (1957); Betti et al., Phys. Plasmas 17, 058102 (2010); Goncharov et al., Phys. Plasmas 21, 056315 (2014); and Glenzer et al., Phys. Plasmas 19, 056318 (2012)]. At high spectral energy, where the x-ray emission from an imploded hydrogen core is optically thin, the emissivity profile can be inferred from the spatially resolved core emission. This emissivity, which can be modeled accurately under hot-core conditions, is dependent almost entirely on the pressure when measured within a restricted spectral range matched to the temperature range anticipated for the emitting volume. In this way, the hot core pressure at the time of peak emission can be inferred from the measured free-free emissivity profile. The pressure and temperature dependences of the x-ray emissivity and the neutron-production rate explain a simple scaling of the total filtered x-ray emission as a constant power of the total neutron yield for implosions of targets of similar design over a broad range of shell implosion isentropes. This scaling behavior has been seen in implosion simulations and is confirmed by measurements of high-isentrope implosions [Sangster et al., Phys. Plasmas 20, 056317 (2013)] on the OMEGA laser system [Boehly et al., Opt. Commun. 133, 495 (1997)]. Attributing the excess emission from less-stable, low-isentrope implosions, above the level expected from this neutron-yield scaling, to the higher emissivity of shell carbon mixed into the implosion's central hot spot, the hot-spot "fuel-shell" mix mass can be inferred.

  8. X-ray continuum as a measure of pressure and fuel–shell mix in compressed isobaric hydrogen implosion cores

    SciTech Connect

    Epstein, R.; Goncharov, V. N.; Marshall, F. J.; Betti, R.; Nora, R.; Christopherson, A. R.; Golovkin, I. E.; MacFarlane, J. J.

    2015-02-01

    Pressure, by definition, characterizes the conditions within an isobaric implosion core at peak compression [Gus’kov et al., Nucl. Fusion 16, 957 (1976); Betti et al., Phys. Plasmas 8, 5257 (2001)] and is a key parameter in quantifying its near-ignition performance [Lawson, Proc. Phys. Soc. London, B 70, 6 (1957); Betti et al., Phys. Plasmas 17, 058102 (2010); Goncharov et al., Phys. Plasmas 21, 056315 (2014); and Glenzer et al., Phys. Plasmas 19, 056318 (2012)]. At high spectral energy, where the x-ray emission from an imploded hydrogen core is optically thin, the emissivity profile can be inferred from the spatially resolved core emission. This emissivity, which can be modeled accurately under hot-core conditions, is dependent almost entirely on the pressure when measured within a restricted spectral range matched to the temperature range anticipated for the emitting volume. In this way, the hot core pressure at the time of peak emission can be inferred from the measured free-free emissivity profile. The pressure and temperature dependences of the x-ray emissivity and the neutron-production rate explain a simple scaling of the total filtered x-ray emission as a constant power of the total neutron yield for implosions of targets of similar design over a broad range of shell implosion isentropes. This scaling behavior has been seen in implosion simulations and is confirmed by measurements of high-isentrope implosions [Sangster et al., Phys. Plasmas 20, 056317 (2013)] on the OMEGA laser system [Boehly et al., Opt. Commun. 133, 495 (1997)]. Attributing the excess emission from less-stable, low-isentrope implosions, above the level expected from this neutron-yield scaling, to the higher emissivity of shell carbon mixed into the implosion’s central hot spot, the hot-spot “fuel–shell” mix mass can be inferred.

  9. X-ray continuum as a measure of pressure and fuel–shell mix in compressed isobaric hydrogen implosion cores

    SciTech Connect

    Epstein, R.; Goncharov, V. N.; Marshall, F. J.; Betti, R.; Nora, R.; Christopherson, A. R.; Golovkin, I. E.; MacFarlane, J. J.

    2015-02-15

    Pressure, by definition, characterizes the conditions within an isobaric implosion core at peak compression [Gus'kov et al., Nucl. Fusion 16, 957 (1976); Betti et al., Phys. Plasmas 8, 5257 (2001)] and is a key parameter in quantifying its near-ignition performance [Lawson, Proc. Phys. Soc. London, B 70, 6 (1957); Betti et al., Phys. Plasmas 17, 058102 (2010); Goncharov et al., Phys. Plasmas 21, 056315 (2014); and Glenzer et al., Phys. Plasmas 19, 056318 (2012)]. At high spectral energy, where the x-ray emission from an imploded hydrogen core is optically thin, the emissivity profile can be inferred from the spatially resolved core emission. This emissivity, which can be modeled accurately under hot-core conditions, is dependent almost entirely on the pressure when measured within a restricted spectral range matched to the temperature range anticipated for the emitting volume. In this way, the hot core pressure at the time of peak emission can be inferred from the measured free-free emissivity profile. The pressure and temperature dependences of the x-ray emissivity and the neutron-production rate explain a simple scaling of the total filtered x-ray emission as a constant power of the total neutron yield for implosions of targets of similar design over a broad range of shell implosion isentropes. This scaling behavior has been seen in implosion simulations and is confirmed by measurements of high-isentrope implosions [Sangster et al., Phys. Plasmas 20, 056317 (2013)] on the OMEGA laser system [Boehly et al., Opt. Commun. 133, 495 (1997)]. Attributing the excess emission from less-stable, low-isentrope implosions, above the level expected from this neutron-yield scaling, to the higher emissivity of shell carbon mixed into the implosion's central hot spot, the hot-spot “fuel–shell” mix mass can be inferred.

  10. Differential proteomics analysis of liver failure in peripheral blood mononuclear cells using isobaric tags for relative and absolute quantitation

    PubMed Central

    Lin, Hua; Tan, Qiu-Pei; Sui, Wei-Guo; Chen, Wen-Biao; Peng, Wu-Jian; Liu, Xing-Chao; Dai, Yong

    2017-01-01

    The aim of the present study was to examine differentially expressed proteome profiles for candidate biomarkers in peripheral blood mononuclear cells (PBMCs) of liver failure (LF) patients. Ten patients were diagnosed as LF and 10 age- and gender-matched subjects were recruited as healthy controls. Isobaric tags for relative and absolute quantitation (iTRAQ)-based quantitative proteomic technology is efficiently applicable for identification and relative quantitation of the proteomes of PBMCs. Eight-plex iTRAQ coupled with strong cation exchange chromatography, and liquid chromatography coupled with tandem mass spectrometry were used to analyze total proteins in LF patients and healthy control subjects. Molecular variations were detected using the iTRAQ method, and western blotting was used to verify the results. LF is a complex type of medical emergency that evolves following a catastrophic insult to the liver, and its outcome remains the most ominous of all gastroenterologic diseases. Serious complications tend to occur during the course of the disease and further exacerbate the problems. Using the iTRAQ method, differentially expressed proteome profiles of LF patients were determined. In the present study, 627 proteins with different expression levels were identified in LF patients compared with the control subjects; with 409 proteins upregulated and 218 proteins downregulated. Among them, four proteins were significantly differentially expressed; acylaminoacyl-peptide hydrolase and WW domain binding protein 2 were upregulated, and resistin and tubulin β 2A class IIa were downregulated. These proteins demonstrated differences in their expression levels compared with other proteins with normal expression levels and the significant positive correlation with LF. The western blot results were consistent with the results from iTRAQ. Thus, investigation of the molecular mechanism of the proteins involved in LF may facilitate an improved understanding of the

  11. High-Field Asymmetric-Waveform Ion Mobility Spectrometry and Electron Detachment Dissociation of Isobaric Mixtures of Glycosaminoglycans

    NASA Astrophysics Data System (ADS)

    Kailemia, Muchena J.; Park, Melvin; Kaplan, Desmond A.; Venot, Andre; Boons, Geert-Jan; Li, Lingyun; Linhardt, Robert J.; Amster, I. Jonathan

    2013-11-01

    High-field asymmetric waveform ion mobility spectrometry (FAIMS) is shown to be capable of resolving isomeric and isobaric glycosaminoglycan negative ions and to have great utility for the analysis of this class of molecules when combined with Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) and tandem mass spectrometry. Electron detachment dissociation (EDD) and other ion activation methods for tandem mass spectrometry can be used to determine the sites of labile sulfate modifications and for assigning the stereochemistry of hexuronic acid residues of glycosaminoglycans (GAGs). However, mixtures with overlapping mass-to-charge values present a challenge, as their precursor species cannot be resolved by a mass analyzer prior to ion activation. FAIMS is shown to resolve two types of mass-to-charge overlaps. A mixture of chondroitin sulfate A (CSA) oligomers with 4-10 saccharides units produces ions of a single mass-to-charge by electrospray ionization, as the charge state increases in direct proportion to the degree of polymerization for these sulfated carbohydrates. FAIMS is shown to resolve the overlapping charge. A more challenging type of mass-to-charge overlap occurs for mixtures of diastereomers. FAIMS is shown to separate two sets of epimeric GAG tetramers. For the epimer pairs, the complexity of the separation is reduced when the reducing end is alkylated, suggesting that anomers are also resolved by FAIMS. The resolved components were activated by EDD and the fragment ions were analyzed by FTICR-MS. The resulting tandem mass spectra were able to distinguish the two epimers from each other.

  12. A Quantitative Tool to Distinguish Isobaric Leucine and Isoleucine Residues for Mass Spectrometry-Based De Novo Monoclonal Antibody Sequencing

    NASA Astrophysics Data System (ADS)

    Poston, Chloe N.; Higgs, Richard E.; You, Jinsam; Gelfanova, Valentina; Hale, John E.; Knierman, Michael D.; Siegel, Robert; Gutierrez, Jesus A.

    2014-07-01

    De novo sequencing by mass spectrometry (MS) allows for the determination of the complete amino acid (AA) sequence of a given protein based on the mass difference of detected ions from MS/MS fragmentation spectra. The technique relies on obtaining specific masses that can be attributed to characteristic theoretical masses of AAs. A major limitation of de novo sequencing by MS is the inability to distinguish between the isobaric residues leucine (Leu) and isoleucine (Ile). Incorrect identification of Ile as Leu or vice versa often results in loss of activity in recombinant antibodies. This functional ambiguity is commonly resolved with costly and time-consuming AA mutation and peptide sequencing experiments. Here, we describe a set of orthogonal biochemical protocols, which experimentally determine the identity of Ile or Leu residues in monoclonal antibodies (mAb) based on the selectivity that leucine aminopeptidase shows for n-terminal Leu residues and the cleavage preference for Leu by chymotrypsin. The resulting observations are combined with germline frequencies and incorporated into a logistic regression model, called Predictor for Xle Sites (PXleS) to provide a statistical likelihood for the identity of Leu at an ambiguous site. We demonstrate that PXleS can generate a probability for an Xle site in mAbs with 96% accuracy. The implementation of PXleS precludes the expression of several possible sequences and, therefore, reduces the overall time and resources required to go from spectra generation to a biologically active sequence for a mAb when an Ile or Leu residue is in question.

  13. High-Field Asymmetric-Waveform Ion Mobility Spectrometry and Electron Detachment Dissociation of Isobaric Mixtures of Glycosaminoglycans

    PubMed Central

    Kailemia, Muchena J.; Park, Melvin; Kaplan, Desmond A.; Venot, Andre; Boons, Geert-Jan; Li, Lingyun; Linhardt, Robert J.; Amster, I. Jonathan

    2014-01-01

    High-field asymmetric waveform ion mobility spectrometry (FAIMS) is shown to be capable of resolving isomeric and isobaric glycosaminoglycan negative ions, and to have great utility for the analysis of this class of molecules when combined with Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) and tandem mass spectrometry. Electron detachment dissociation (EDD) and other ion activation methods for tandem mass spectrometry can be used to determine the sites of labile sulfate modifications and for assigning the stereochemistry of hexuronic acid residues of GAGs. However, mixtures with overlapping mass-to-charge values present a challenge, as their precursor species cannot be resolved by a mass analyzer prior to ion activation. FAIMS is shown to resolve two types of mass-to-charge overlaps. A mixture of chondroitin sulfate A (CSA) oligomers with 4–10 saccharides units produces ions of a single mass-to-charge by electrospray ionization, as the charge state increases in direct proportion to the degree of polymerization for these sulfated carbohydrates. FAIMS is shown to resolve the overlapping charge. A more challenging type of mass-to-charge overlap occurs for mixtures of diastereomers. FAIMS is shown to separate two sets of epimeric GAG tetramers. For the epimer pairs, the complexity of the separation is reduced when the reducing end is alkylated, suggesting that anomers are also resolved by FAIMS. The resolved components were activated by EDD and the fragment ions were analyzed by FTICR-MS. The resulting tandem mass spectra were able to distinguish the two epimers from each other. PMID:24254578

  14. Molecular dynamics in the isothermal-isobaric ensemble: the requirement of a "shell" molecule. II. Simulation results.

    PubMed

    Uline, Mark J; Corti, David S

    2005-10-22

    The results of a series of constant pressure and temperature molecular-dynamics (MD) simulation studies based on the rigorous shell particle formulation of the isothermal-isobaric (NpT) ensemble are presented. These MD simulations validate the newly proposed constant pressure equations of motion in which a "shell" particle is used to define uniquely the volume of the system [M. J. Uline and D. S. Corti, J. Chem. Phys. (to be published), preceding paper]. Ensemble averages obtained with the new MD NpT algorithm match the ensemble averages obtained using the previously derived shell particle Monte Carlo NpT method [D. S. Corti, Mol. Phys. 100, 1887 (2002)]. In addition, we also verify that the Hoover NpT MD algorithm [W. G. Hoover, Phys. Rev. A 31, 1695 (1985); 34, 2499 (1986)] generates the correct ensemble averages, though only when periodic boundary conditions are employed. The extension of the shell particle MD algorithm to multicomponent systems is also discussed, in which we show for equilibrium properties that the identity of the shell particle is completely arbitrary when periodic boundary conditions are applied. Self-diffusion coefficients determined with the shell particle equations of motion are also identical to those obtained in other ensembles. Finally, since the mass of the shell particle is known, the system itself, and not a piston of arbitrary mass, controls the time scales for internal pressure and volume fluctuations. We therefore consider the effects of the shell particle on the dynamics of the system. Overall, the shell particle MD algorithm is an effective simulation method for studying systems exposed to a constant external pressure and may provide an advantage over other existing constant pressure approaches when developing nonequilibrium MD methods.

  15. Two-mica and tourmaline leucogranites from the Everest Makalu region (Nepal Tibet). Himalayan leucogranite genesis by isobaric heating?

    NASA Astrophysics Data System (ADS)

    Visonà, Dario; Lombardo, Bruno

    2002-06-01

    In the Higher Himalaya of the region from Cho Oyu to the Arun valley northeast of Makalu, the Miocene leucogranites are not hosted only in the upper High Himalayan Crystallines (HHC); a network of dykes also cuts the lower HHC and the Lesser Himalayan Crystallines (LHC). The plutons and dykes are mainly composed of two-mica (muscovite+biotite±tourmaline±cordierite±andalusite±sillimanite) leucogranite, with tourmaline≤2.6% and biotite>1.5% modal, and tourmaline (muscovite+tourmaline±biotite±sillimanite ±garnet±kyanite±andalusite±spinel±corundum) leucogranite, with tourmaline>2.2% and biotite<1.5% modal. Both leucogranite types were produced by partial melting in the andalusite-sillimanite facies series, under LP/HT conditions constrained by the occurrence of peritectic andalusite and cordierite. The geochemical features of the leucogranites suggest that tourmaline leucogranite was produced by muscovite dehydration melting in muscovite-rich metapelites at P˜350 MPa and T≥640°C, whereas two-mica leucogranite was produced by biotite dehydration melting in biotite-rich metapelites at P˜300 MPa and T≥660-710 °C. Melting in fertile muscovite-rich metapelites of the top of both the HHC and LHC produced magmas which were emplaced at the same structural level in which they had been generated. Melting in the biotite-rich gneiss of both the HHC and LHC produced hotter magmas which were transported upwards by dyking and eventually coalesced in the plutons of the upper HHC. A similar process also produced a network of two-mica granite at the top of the LHC in the Ama Drime-Nyönno Ri Range northeast of Makalu. The prograde character of leucogranite melt-producing reactions in the Everest-Makalu area suggests that, here, the generation of Miocene leucogranites took place in a regime of nearly isobaric heating following nearly adiabatic decompression.

  16. Quantitative analysis of human cerebrospinal fluid proteins using a combination of cysteine tagging and amine-reactive isobaric labeling.

    PubMed

    Giron, Priscille; Dayon, Loïc; Turck, Natacha; Hoogland, Christine; Sanchez, Jean-Charles

    2011-01-07

    Highly complex and dynamic protein mixtures are hardly comprehensively resolved by direct shotgun proteomic analysis. As many proteins of biological interest are of low abundance, numerous analytical methodologies have been developed to reduce sample complexity and go deeper into proteomes. The present work describes an analytical strategy to perform cysteinyl-peptide subset enrichment and relative quantification through successive cysteine and amine-isobaric tagging. A cysteine-reactive covalent capture tag (C³T) allowed derivatization of cysteines and specific isolation on a covalent capture (CC) resin. The 6-plex amine-reactive tandem mass tags (TMT) served for relative quantification of the targeted peptides. The strategy was first evaluated on a model protein mixture with increasing concentrations to assess the specificity of the enrichment and the quantitative performances of the workflow. It was then applied to human cerebrospinal fluid (CSF) from post-mortem and ante-mortem samples. These studies confirmed the specificity of the C³T and the CC technique to cysteine-containing peptides. The model protein mixture analysis showed high precision and accuracy of the quantification with coefficients of variation and mean absolute errors of less than 10% on average. The CSF experiments demonstrated the potential of the strategy to study complex biological samples and identify differential brain-related proteins. In addition, the quantification data were highly correlated with a classical TMT experiment (i.e., without C³T cysteine-tagging and enrichment steps). Altogether, these results legitimate the use of this quantitative C³T strategy to enrich and relatively quantify cysteine-containing peptides in complex mixtures.

  17. Battery hydrometer with analog output

    SciTech Connect

    Patis, B.L.

    1982-09-21

    There is disclosed a battery hydrometer for providing an analog electrical signal having a magnitude related to the specific gravity of a battery electrolyte. The hydrometer includes a source of radiation for providing a detectable beam of radiation and a piston member arranged to be submerged within the electrolyte and to intercept and modulate the beam of radiation in response to the specific gravity of the electrolyte. The piston member is suspended within the electrolyte by a spring which exerts a compressive force upon the piston member against which the electrolyte must act. The hydrometer further includes a radiation detector aligned with the radiation source for providing an analog electrical signal having a magnitude responsive to the modulated beam of radiation.

  18. Synaptic dynamics in analog VLSI.

    PubMed

    Bartolozzi, Chiara; Indiveri, Giacomo

    2007-10-01

    Synapses are crucial elements for computation and information transfer in both real and artificial neural systems. Recent experimental findings and theoretical models of pulse-based neural networks suggest that synaptic dynamics can play a crucial role for learning neural codes and encoding spatiotemporal spike patterns. Within the context of hardware implementations of pulse-based neural networks, several analog VLSI circuits modeling synaptic functionality have been proposed. We present an overview of previously proposed circuits and describe a novel analog VLSI synaptic circuit suitable for integration in large VLSI spike-based neural systems. The circuit proposed is based on a computational model that fits the real postsynaptic currents with exponentials. We present experimental data showing how the circuit exhibits realistic dynamics and show how it can be connected to additional modules for implementing a wide range of synaptic properties.

  19. Analog Nonvolatile Computer Memory Circuits

    NASA Technical Reports Server (NTRS)

    MacLeod, Todd

    2007-01-01

    In nonvolatile random-access memory (RAM) circuits of a proposed type, digital data would be stored in analog form in ferroelectric field-effect transistors (FFETs). This type of memory circuit would offer advantages over prior volatile and nonvolatile types: In a conventional complementary metal oxide/semiconductor static RAM, six transistors must be used to store one bit, and storage is volatile in that data are lost when power is turned off. In a conventional dynamic RAM, three transistors must be used to store one bit, and the stored bit must be refreshed every few milliseconds. In contrast, in a RAM according to the proposal, data would be retained when power was turned off, each memory cell would contain only two FFETs, and the cell could store multiple bits (the exact number of bits depending on the specific design). Conventional flash memory circuits afford nonvolatile storage, but they operate at reading and writing times of the order of thousands of conventional computer memory reading and writing times and, hence, are suitable for use only as off-line storage devices. In addition, flash memories cease to function after limited numbers of writing cycles. The proposed memory circuits would not be subject to either of these limitations. Prior developmental nonvolatile ferroelectric memories are limited to one bit per cell, whereas, as stated above, the proposed memories would not be so limited. The design of a memory circuit according to the proposal must reflect the fact that FFET storage is only partly nonvolatile, in that the signal stored in an FFET decays gradually over time. (Retention times of some advanced FFETs exceed ten years.) Instead of storing a single bit of data as either a positively or negatively saturated state in a ferroelectric device, each memory cell according to the proposal would store two values. The two FFETs in each cell would be denoted the storage FFET and the control FFET. The storage FFET would store an analog signal value

  20. Classical Analog to Entanglement Reversibility

    NASA Astrophysics Data System (ADS)

    Chitambar, Eric; Fortescue, Ben; Hsieh, Min-Hsiu

    2015-08-01

    In this Letter we study the problem of secrecy reversibility. This asks when two honest parties can distill secret bits from some tripartite distribution pX Y Z and transform secret bits back into pX Y Z at equal rates using local operation and public communication. This is the classical analog to the well-studied problem of reversibly concentrating and diluting entanglement in a quantum state. We identify the structure of distributions possessing reversible secrecy when one of the honest parties holds a binary distribution, and it is possible that all reversible distributions have this form. These distributions are more general than what is obtained by simply constructing a classical analog to the family of quantum states known to have reversible entanglement. An indispensable tool used in our analysis is a conditional form of the Gács-Körner common information.

  1. Superconducting Analog to Digital Converters

    DTIC Science & Technology

    1991-09-01

    superconductivity, Josephson junctions, and superconducting quantum interference devices ( SQUIDs ) are briefly described. Various techniques to perform analog-to...deployment in the 1990s may require a dynamic range in excess of 90 dB (15- bit precision) [3]. However, at the present time, A/D conversion with 16-bit...Interference Devices ( SQUIDs ). JOSEPHSON EFFECTS AND JUNCTIONS Consider a very thin, non-superconducting region separating two superconductors. In 1962

  2. Neurotoxicology of Synthetic Cathinone Analogs.

    PubMed

    Angoa-Pérez, Mariana; Anneken, John H; Kuhn, Donald M

    The present review briefly explores the neurotoxic properties of methcathinone, mephedrone, methylone, and methylenedioxypyrovalerone (MDPV), four synthetic cathinones most commonly found in "bath salts." Cathinones are β-keto analogs of the commonly abused amphetamines and display pharmacological effects resembling cocaine and amphetamines, but despite their commonalities in chemical structures, synthetic cathinones possess distinct neuropharmacological profiles and produce unique effects. Among the similarities of synthetic cathinones with their non-keto analogs are their targeting of monoamine systems, the release of neurotransmitters, and their stimulant properties. Most of the literature on synthetic cathinones has focused on describing their properties as psychostimulants, their behavioral effects on locomotion, memory, and potential for abuse, whereas descriptions of their neurotoxic properties are not abundant. The biochemical gauges of neurotoxicity induced by non-keto analogs are well studied in humans and experimental animals and include their ability to induce neuroinflammation, oxidative stress, excitotoxicity, temperature alterations as well as dysregulation of neurotransmitter systems and induce changes in monoamine transporters and receptors. These neurotoxicity gauges will serve as parameters to discuss the effects of the four previously mentioned synthetic cathinones alone or in combination with either another cathinone or with some of their non-keto analogs. Bath salts are not a defined combination of drugs and may consist of one synthetic cathinone compound or combinations of more cathinones. Furthermore, this review also presents some of the mechanisms that are thought to underlie this toxicity. A better understanding of the cellular and molecular mechanisms involved in the synthetic cathinones-induced neurotoxicity should contribute to generate modern therapeutic approaches to prevent or attenuate the adverse consequences of use of these

  3. Health as an analogical concept.

    PubMed

    Mordacci, R

    1995-10-01

    This article examines the normative structure of the concept of health and tries to suggest an account of it in a phenomenological-hermeneutic framework. It is argued that the concept of health has a logical priority to illness, though the latter has an experiential priority. The fundamental feature of the concept of health as discussed in the literature is initially recognized in the notion of 'norm', in both the bio-statistical and normative-ideal sense. An analysis of this body of literature reveals some weaknesses in bio-statistical definitions of health as well as in those normative ones which endorse a value-relativity thesis. An approach based on the analogical structure of language is then advanced. In this framework, the notion of biological normativeness proposed by G. Canguilhem is connected with an analysis of the language of health through etymologies. It is argued that health can be characterized as an analogy of 'plenitude', which is the common ideal reference of the various health-concepts. The analogical structuring of language allows the recognition of different levels of meaning, and therefore of different kinds of normativeness (biological, mental, social, moral). Some hints of a theory of health deriving from this framework are then given.

  4. Simple Electronic Analog of a Josephson Junction.

    ERIC Educational Resources Information Center

    Henry, R. W.; And Others

    1981-01-01

    Demonstrates that an electronic Josephson junction analog constructed from three integrated circuits plus an external reference oscillator can exhibit many of the circuit phenomena of a real Josephson junction. Includes computer and other applications of the analog. (Author/SK)

  5. Thermal analog device reduces machining errors

    NASA Technical Reports Server (NTRS)

    Mcclure, E. R.

    1972-01-01

    Thermal analog devices predict thermal expansion and contraction of machine structures subjected to various heat inputs. Analog devices correct positioning of machine tools to compensate for distortion of machine frame.

  6. Basic Electricity--a Novel Analogy.

    ERIC Educational Resources Information Center

    Grant, Richard

    1996-01-01

    Uses the analogy of water flow to introduce concepts in basic electricity. Presents a demonstration that uses this analogy to help students grasp the relationship between current, voltage, and resistance. (JRH)

  7. Simple Electronic Analog of a Josephson Junction.

    ERIC Educational Resources Information Center

    Henry, R. W.; And Others

    1981-01-01

    Demonstrates that an electronic Josephson junction analog constructed from three integrated circuits plus an external reference oscillator can exhibit many of the circuit phenomena of a real Josephson junction. Includes computer and other applications of the analog. (Author/SK)

  8. Program Documentation for the Analog Digitization Program,

    DTIC Science & Technology

    COMPUTER PROGRAM DOCUMENTATION, *ANALOG TO DIGITAL CONVERTERS, REAL TIME, COMPUTER LOGIC, INPUT OUTPUT PROCESSING, SAMPLING, INPUT OUTPUT DEVICES...FLOW CHARTING, ANALOG SIGNALS, DISK RECORDING SYSTEMS, DIGITAL RECORDING SYSTEMS, ASSEMBLY LANGUAGES.

  9. Third order digital-to-analog converter

    NASA Technical Reports Server (NTRS)

    Dotson, W. P.

    1972-01-01

    System, consisting of sample and hold digital-to-analog converter, clock circuit, sample delay circuit, initial condition circuit and interpolator circuit, improves accuracy of reconstructed analog signal without increasing sample rates.

  10. Double-beta-decay Q values of {sup 74}Se and {sup 76}Ge

    SciTech Connect

    Mount, Brianna J.; Redshaw, Matthew; Myers, Edmund G.

    2010-03-15

    The atomic masses of {sup 74}Ge, {sup 74}Se, {sup 76}Ge, and {sup 76}Se have been determined from cyclotron frequency ratios of pairs of ions simultaneously trapped in a cryogenic Penning trap. Allowing for cancellation of systematic errors in the mass differences between isobars, we determine the Q value for double-electron capture of {sup 74}Se to be 1209.240(7) keV, and the Q value for double-electron emission of {sup 76}Ge to be 2039.061(7) keV. The new Q{sub 2EC} value for {sup 74}Se precludes a large resonant enhancement for neutrinoless double-electron capture.

  11. Hegel, Analogy, and Extraterrestrial Life

    NASA Astrophysics Data System (ADS)

    Ross, Joseph T.

    Georg Wilhelm Friedrich Hegel rejected the possibility of life outside of the Earth, according to several scholars of extraterrestrial life. Their position is that the solar system and specifically the planet Earth is the unique place in the cosmos where life, intelligence, and rationality can be. The present study offers a very different interpretation of Hegel's statements about the place of life on Earth by suggesting that, although Hegel did not believe that there were other solar systems where rationality is present, he did in fact suggest that planets in general, not the Earth exclusively, have life and possibly also intelligent inhabitants. Analogical syllogisms are superficial, according to Hegel, insofar as they try to conclude that there is life on the Moon even though there is no evidence of water or air on that body. Similar analogical arguments for life on the Sun made by Johann Elert Bode and William Herschel were considered by Hegel to be equally superficial. Analogical arguments were also used by astronomers and philosophers to suggest that life could be found on other planets in our solar system. Hegel offers no critique of analogical arguments for life on other planets, and in fact Hegel believed that life would be found on other planets. Planets, after all, have meteorological processes and therefore are "living" according to his philosophical account, unlike the Moon, Sun, and comets. Whereas William Herschel was already finding great similarities between the Sun and the stars and had extended these similarities to the property of having planets or being themselves inhabitable worlds, Hegel rejected this analogy. The Sun and stars have some properties in common, but for Hegel one cannot conclude from these similarities to the necessity that stars have planets. Hegel's arguments against the presence of life in the solar system were not directed against other planets, but rather against the Sun and Moon, both of which he said have a different

  12. Stacked-Gate FET's For Analog Memory Elements

    NASA Technical Reports Server (NTRS)

    Thakoor, Anilkumar P.; Moopenn, Alexander W.

    1991-01-01

    Three-terminal, double-stacked-gate field-effect transistor (FET), developed as analog memory element. Particularly suited for use as synapse with variable connection strength in electronic neural network. Provides programmable, nonvolatile resistive connection, somewhat in manner of porous-gate FET described in "Porous-Floating-Gate Field-Effect Transistor" (NPO-17532). Resembles commercial erasable programmable read-only memory (EPROM) device, except for thickness of layers of silicon dioxide electrically isolating gates. Either p-channel or n-channel device.

  13. Stacked-Gate FET's For Analog Memory Elements

    NASA Technical Reports Server (NTRS)

    Thakoor, Anilkumar P.; Moopenn, Alexander W.

    1991-01-01

    Three-terminal, double-stacked-gate field-effect transistor (FET), developed as analog memory element. Particularly suited for use as synapse with variable connection strength in electronic neural network. Provides programmable, nonvolatile resistive connection, somewhat in manner of porous-gate FET described in "Porous-Floating-Gate Field-Effect Transistor" (NPO-17532). Resembles commercial erasable programmable read-only memory (EPROM) device, except for thickness of layers of silicon dioxide electrically isolating gates. Either p-channel or n-channel device.

  14. The Micro-Category Account of Analogy

    ERIC Educational Resources Information Center

    Green, Adam E.; Fugelsang, Jonathan A.; Kraemer, David J. M.; Dunbar, Kevin N.

    2008-01-01

    Here, we investigate how activation of mental representations of categories during analogical reasoning influences subsequent cognitive processing. Specifically, we present and test the central predictions of the "Micro-Category" account of analogy. This account emphasizes the role of categories in aligning terms for analogical mapping. In a…

  15. Analogical Reasoning: A Review of the Literature.

    ERIC Educational Resources Information Center

    Dawis, Rene V.; Siojo, Luis T.

    The mathematical and philosophical origins of "analogy" are described and their influence on the thinking of intelligence theorists is traced. Theories of intelligence and cognition bearing on analogical reasoning are examined, specifically those of Spearman, Thorndike, Guilford and Piaget. The analogy test item is shown to be a paradigm…

  16. Reasoning by Analogy in Constructing Mathematical Ideas.

    ERIC Educational Resources Information Center

    English, Lyn D.

    A powerful way of understanding something new is by analogy with something already known. An analogy is defined as a mapping from one structure, which is already known (the base or source), to another structure that is to be inferred or discovered (the target). The research community has given considerable attention to analogical reasoning in the…

  17. Are all analogies created equal? Prefrontal cortical functioning may predict types of analogical reasoning.

    PubMed

    Chrysikou, Evangelia G; Thompson-Schill, Sharon L

    2010-06-01

    Abstract The proposed theory can account for analogies based on learned relationships between elements in the source and target domains. However, its explanatory power regarding the discovery of new relationships during analogical reasoning is limited. We offer an alternative perspective for the role of PFC in analogical thought that may better address different types of analogical mappings.

  18. Isobaric Inert Gas Counterdiffusion,

    DTIC Science & Technology

    1982-11-01

    20 minutes. A second group of animals pretreated with 10 milligrams of valium, intramuscularly, showed a time lag of 248 minutes with an SE of 24...low z 20 - T x Pf Is. Cc) tPo L Q" TIME - 15- . N 200 w X N= a30 _. Dr O N=aIO " H 1 0 z1 0-- , / a- . 0 05 1- 20 CRUSHING PRESSURE PCRUSH Pm-Po

  19. Vadose zone isobaric well

    DOEpatents

    Hubbell, Joel M.; Sisson, James B.

    2001-01-01

    A deep tensiometer is configured with an outer guide tube having a vented interval along a perforate section at its lower end, which is isolated from atmospheric pressure at or above grade. A transducer having a monitoring port and a reference port is located within a coaxial inner guide tube. The reference port of the transducer is open to the vented interval of the outer guide tube, which has the same gas pressure as in the sediment surrounding the tensiometer. The reference side of the pressure transducer is thus isolated from the effects of atmospheric pressure changes and relative to pressure changes in the material surrounding the tensiometer measurement location and so it is automatically compensated for such pressure changes.

  20. Otto Stern and the double bank shot

    NASA Astrophysics Data System (ADS)

    Zare, R. N.

    1988-06-01

    In analogy to a double surface scattering study of Estermann, Frisch and Stern for selecting and detecting the velocity of a beam of particles, it is proposed to use double surface scattering to investigate the collision dynamics of a beam of polarized particles with a known surface. In this proposed experiment, the first surface scattering event prepares a polarized (aligned/oriented) beam of particles, and the second surface scattering event permits the measurement of how the polarized beam interacts with the surface under study.

  1. Parametric study and characterization of the isobaric thermomechanical transformation fatigue of nickel-rich NiTi SMA actuators

    NASA Astrophysics Data System (ADS)

    Bertacchini, Olivier W.; Schick, Justin; Lagoudas, Dimitris C.

    2009-03-01

    The recent development of various aerospace applications utilizing Ni-rich NiTi Shape memory Alloys (SMAs) as actuators motivated the need to characterize the cyclic response and the transformation fatigue behavior of such alloys. The fatigue life validation and certification of new designs is required in order to be implemented and used in future applications. For that purpose, a custom built fatigue test frame was designed to perform isobaric thermally induced transformation cycles on small dogbones SMA actuators (test gauge cross-section up to: 1.270 x 0.508 mm2). A parametric study on the cyclic response and transformation fatigue behavior of Ni-rich NiTi SMAs led to the optimization of several material/process and test parameters, namely: the applied stress range, the heat treatment, the heat treatment environment and the specimen thickness. However, fatigue testing was performed in a chilled waterless glycol environment maintained at a temperature of 5°C that showed evidence of corrosion-assisted transformation fatigue failure. Therefore, it was necessary to build a fatigue test frame that would employ a dry and inert cooling methodology to get away from any detrimental interactions between the specimens and the cooling medium (corrosion). The selected cooling method was gaseous nitrogen, sprayed into a thermally insulated chamber, maintaining a temperature of -20°C. The design of the gaseous nitrogen cooling was done in such a way that the actuation frequency is similar to the one obtained using the original design (~ 0.1 Hz). For both cooling methods, Joule resistive heating was used to heat the specimens. In addition and motivated by the difference in surface quality resulting from different material processing such as EDM wire cutting and heat treatments, EDM recast layer and oxide layer were removed. The removal was followed by an ultra-fine polish (0.05 μm) that was performed on a subset of the fatigue specimens. Experimental results are presented

  2. Quantitative Proteomic Analysis of Wheat Seeds during Artificial Ageing and Priming Using the Isobaric Tandem Mass Tag Labeling

    PubMed Central

    Lv, Yangyong; Zhang, Shuaibing; Wang, Jinshui; Hu, Yuansen

    2016-01-01

    Wheat (Triticum aestivum L.) is an important crop worldwide. The physiological deterioration of seeds during storage and seed priming is closely associated with germination, and thus contributes to plant growth and subsequent grain yields. In this study, wheat seeds during different stages of artificial ageing (45°C; 50% relative humidity; 98%, 50%, 20%, and 1% Germination rates) and priming (hydro-priming treatment) were subjected to proteomics analysis through a proteomic approach based on the isobaric tandem mass tag labeling. A total of 162 differentially expressed proteins (DEPs) mainly involved in metabolism, energy supply, and defense/stress responses, were identified during artificial ageing and thus validated previous physiological and biochemical studies. These DEPs indicated that the inability to protect against ageing leads to the incremental decomposition of the stored substance, impairment of metabolism and energy supply, and ultimately resulted in seed deterioration. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that the up-regulated proteins involved in seed ageing were mainly enriched in ribosome, whereas the down-regulated proteins were mainly accumulated in energy supply (starch and sucrose metabolism) and stress defense (ascorbate and aldarate metabolism). Proteins, including hemoglobin 1, oleosin, agglutinin, and non-specific lipid-transfer proteins, were first identified in aged seeds and might be regarded as new markers of seed deterioration. Of the identified proteins, 531 DEPs were recognized during seed priming compared with unprimed seeds. In contrast to the up-regulated DEPs in seed ageing, several up-regulated DEPs in priming were involved in energy supply (tricarboxylic acid cycle, glycolysis, and fatty acid oxidation), anabolism (amino acids, and fatty acid synthesis), and cell growth/division. KEGG and protein-protein interaction analysis indicated that the up-regulated proteins in seed priming were mainly

  3. Quantitative Proteomic Analysis of Wheat Seeds during Artificial Ageing and Priming Using the Isobaric Tandem Mass Tag Labeling.

    PubMed

    Lv, Yangyong; Zhang, Shuaibing; Wang, Jinshui; Hu, Yuansen

    2016-01-01

    Wheat (Triticum aestivum L.) is an important crop worldwide. The physiological deterioration of seeds during storage and seed priming is closely associated with germination, and thus contributes to plant growth and subsequent grain yields. In this study, wheat seeds during different stages of artificial ageing (45°C; 50% relative humidity; 98%, 50%, 20%, and 1% Germination rates) and priming (hydro-priming treatment) were subjected to proteomics analysis through a proteomic approach based on the isobaric tandem mass tag labeling. A total of 162 differentially expressed proteins (DEPs) mainly involved in metabolism, energy supply, and defense/stress responses, were identified during artificial ageing and thus validated previous physiological and biochemical studies. These DEPs indicated that the inability to protect against ageing leads to the incremental decomposition of the stored substance, impairment of metabolism and energy supply, and ultimately resulted in seed deterioration. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that the up-regulated proteins involved in seed ageing were mainly enriched in ribosome, whereas the down-regulated proteins were mainly accumulated in energy supply (starch and sucrose metabolism) and stress defense (ascorbate and aldarate metabolism). Proteins, including hemoglobin 1, oleosin, agglutinin, and non-specific lipid-transfer proteins, were first identified in aged seeds and might be regarded as new markers of seed deterioration. Of the identified proteins, 531 DEPs were recognized during seed priming compared with unprimed seeds. In contrast to the up-regulated DEPs in seed ageing, several up-regulated DEPs in priming were involved in energy supply (tricarboxylic acid cycle, glycolysis, and fatty acid oxidation), anabolism (amino acids, and fatty acid synthesis), and cell growth/division. KEGG and protein-protein interaction analysis indicated that the up-regulated proteins in seed priming were mainly

  4. Simultaneous quantification of protein phosphorylation sites using liquid chromatography-tandem mass spectrometry-based targeted proteomics: a linear algebra approach for isobaric phosphopeptides.

    PubMed

    Xu, Feifei; Yang, Ting; Sheng, Yuan; Zhong, Ting; Yang, Mi; Chen, Yun

    2014-12-05

    As one of the most studied post-translational modifications (PTM), protein phosphorylation plays an essential role in almost all cellular processes. Current methods are able to predict and determine thousands of phosphorylation sites, whereas stoichiometric quantification of these sites is still challenging. Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS)-based targeted proteomics is emerging as a promising technique for site-specific quantification of protein phosphorylation using proteolytic peptides as surrogates of proteins. However, several issues may limit its application, one of which relates to the phosphopeptides with different phosphorylation sites and the same mass (i.e., isobaric phosphopeptides). While employment of site-specific product ions allows for these isobaric phosphopeptides to be distinguished and quantified, site-specific product ions are often absent or weak in tandem mass spectra. In this study, linear algebra algorithms were employed as an add-on to targeted proteomics to retrieve information on individual phosphopeptides from their common spectra. To achieve this simultaneous quantification, a LC-MS/MS-based targeted proteomics assay was first developed and validated for each phosphopeptide. Given the slope and intercept of calibration curves of phosphopeptides in each transition, linear algebraic equations were developed. Using a series of mock mixtures prepared with varying concentrations of each phosphopeptide, the reliability of the approach to quantify isobaric phosphopeptides containing multiple phosphorylation sites (≥ 2) was discussed. Finally, we applied this approach to determine the phosphorylation stoichiometry of heat shock protein 27 (HSP27) at Ser78 and Ser82 in breast cancer cells and tissue samples.

  5. Rare evidence for formation of garnet + corundum during isobaric cooling of ultrahigh temperature metapelites: New insights for retrograde P-T trajectory of the Highland Complex, Sri Lanka

    NASA Astrophysics Data System (ADS)

    Dharmapriya, P. L.; Malaviarachchi, Sanjeeva P. K.; Galli, Andrea; Su, Ben-Xun; Subasinghe, N. D.; Dissanayake, C. B.

    2015-04-01

    We report the occurrence of coexisting garnet + corundum in spinel- and corundum-bearing, garnet-sillimanite-biotite-graphite gneiss (pelitic granulites) from the Highland Complex (HC), Sri Lanka. In the investigated pelitic granulites, two domains such as quartz-saturated and quartz-undersaturated are distinguishable. The quartz-saturated domains consist of porphyroblastic garnet, quartz, plagioclase, alkali-feldspar and biotite flakes rimming garnet. The quartz-undersaturated domains are constituted of two generations of garnet (Grt1 and Grt2), sillimanite, plagioclase, alkali-feldspar, corundum, spinel and biotite. Grt1 encloses rare Ti-rich biotite and numerous rutile needles and apatite rods. Grt2 contains rare sillimanite and/or spinel inclusions. Corundum occurs in mutual contact with Grt2, partially embedded at the rim or as an inclusions in Grt2. Thermobarometry on inclusion phases in Grt1 indicates that during the prograde history pelitic granulites attained a P of 10.5-11 kbar at T of ~ 850 °C. Textural observations coupled with both pseudosections calculated in the NCKFMASHTMnO system and Ti-in-Garnet geothermobarometry suggest that peak metamorphism occurred at ultrahigh temperature (UHT) conditions of 950-975 °C and pressures of 9-9.5 kbar. Peak T was followed by a period of isobaric cooling that formed corundum and Grt2 at approx. 930 °C along with exsolution of rutile needles and apatite rods in Grt1. Thermodynamic modelling confirms that corundum appears along an isobaric cooling path at about 920-930 °C and 9-9.5 kbar. Therefore, the investigated granulites provide a rare example of post-peak crystallization of garnet + corundum along a retrograde metamorphic trajectory under UHT conditions. Thus, isobaric cooling at the base of the crust could be regarded as an alternative process to form coexisting garnet + corundum.

  6. A comparison of thoracic spinal anesthesia with low-dose isobaric and low-dose hyperbaric bupivacaine for orthopedic surgery: A randomized controlled trial

    PubMed Central

    Imbelloni, Luiz Eduardo; Gouveia, Marildo A.

    2014-01-01

    Background: The thoracic spinal anesthesia was first described in 1909 and recently revised for various surgical procedures. This is a prospective study aims to evaluate the parameters of the thoracic spinal anesthesia (latency, motor block and paresthesia), the incidence of cardiovascular changes and complications comparing low doses of isobaric and hyperbaric bupivacaine. Materials and Methods: A total of 200 orthopedic patients operated under spinal anesthesia were included in this study. Spinal anesthesia was between T9-T10, with a 27G cutting point or pencil tip in lateral or sitting. Spinal anesthesia was performed with 0.5% bupivacaine isobaric or hyperbaric. Patients remained in cephalad or head down position 10-20° for 10 minutes. We evaluated the demographics, analgesia, and degree of motor block, incidence of paresthesia, bradycardia, hypotension, anesthesia success and neurological complications. Results: All patients developed spinal and there was no failure. The solution did not affect the onset of the blockade. The duration of motor block was greater than the sensitive with isobaric. The duration of sensory block was greater than the motor block with hyperbaric solution. The incidence of paresthesia was 4%, with no difference between the needles. The incidence of hypotension was 12.5% with no difference between the solutions. There was no neurological damage in all patients. Conclusion: The beginning of the block is fast regardless of the solution used. By providing a sensory block of longer duration than the motor block hyperbaric bupivacaine is reflected in a better indication. Thoracic spinal anesthesia provides excellent anesthesia for lower limb orthopedic surgery PMID:25886099

  7. Measurement and isobar-model analysis of the doubly differential cross section for the. pi. /sup +/ produced in. pi. /sup -/p. -->. pi. /sup +/. pi. /sup -/n

    SciTech Connect

    Manley, D.M.

    1981-11-01

    The doubly differential cross section d/sup 2/sigma/d..cap omega..dT for ..pi../sup +/ mesons produced in the reaction ..pi../sup -/p ..-->.. ..pi../sup +/..pi../sup -/n was measured at 203, 230, 256, and 358 MeV with a single-arm magnetic spectrometer. A set of five previous measurements at 254, 280, 292, 331, and 356 MeV was reanalyzed with the new measurements. Integrated cross sections were calculated for the combined data set with unprecedented accuracy for this energy range. The chiral-symmetry-breaking parameter was determined to be epsilon = -0.03 +- 0.26 by extrapolating the mean square modulus of the matrix element to threshold and comparing the threshold matrix element with the prediction of soft-pion theory. This value of epsilon is consistent with zero as required by the Weinberg Lagrangian. Measurements at the three highest energies were compared with the results of an isobar-model analysis of bubble-chamber events by an LBL-SLAC collaboration. After allowing for an overall normalization difference, the measurements at 331 and 358 MeV were in excellent agreement with the results of their analysis. The measurement at 292 MeV required variation of the PS11(epsilonN) amplitude, as well as the overall normalization, which could be due to the limited number of bubble-chamber events available for the LBL-SLAC analysis at this energy. A partial-wave analysis of the measurements was also carried out with the VPI isobar model. Within this model, the matrix element contains a background term calculated from a phenomenological ..pi..N Lagrangian that is consistent with the hypotheses of current algebra and PCAC. The reaction was found to be dominated by the initial P11 wave. Production of the ..delta.. isobar from initial D waves was found to be significant at the two highest energies.

  8. Evidence for a breakdown of the isobaric multiplet mass equation: A study of the A=35,T=3/2 isospin quartet

    SciTech Connect

    Yazidjian, C.; Beck, D.; Herfurth, F.; Audi, G.; Guenaut, C.; Lunney, D.; Blaum, K.; George, S.; Herlert, A.; Schweikhard, L.; Kellerbauer, A.; Kluge, H.-J.

    2007-08-15

    Mass measurements on radionuclides along the potassium isotope chain have been performed with the ISOLTRAP Penning trap mass spectrometer. For {sup 35}K (T{sub 1/2}=178 ms) to {sup 46}K (T{sub 1/2}=105 s) relative mass uncertainties of 2x10{sup -8} and better have been achieved. The accurate mass determination of {sup 35}K ({delta}m=0.54 keV) has been exploited to test the isobaric multiplet mass equation for the A=35,T=3/2 isospin quartet. The experimental results indicate a deviation from the generally adopted quadratic form.

  9. On the divergence of triangular and eccentric spherical sums of double Fourier series

    SciTech Connect

    Karagulyan, G A

    2016-01-31

    We construct a continuous function on the torus with almost everywhere divergent triangular sums of double Fourier series. We also prove an analogous theorem for eccentric spherical sums. Bibliography: 14 titles.

  10. Reliability of analog quantum simulation

    DOE PAGES

    Sarovar, Mohan; Zhang, Jun; Zeng, Lishan

    2017-01-03

    Analog quantum simulators (AQS) will likely be the first nontrivial application of quantum technology for predictive simulation. However, there remain questions regarding the degree of confidence that can be placed in the results of AQS since they do not naturally incorporate error correction. Specifically, how do we know whether an analog simulation of a quantum model will produce predictions that agree with the ideal model in the presence of inevitable imperfections? At the same time there is a widely held expectation that certain quantum simulation questions will be robust to errors and perturbations in the underlying hardware. Resolving these twomore » points of view is a critical step in making the most of this promising technology. In this paper we formalize the notion of AQS reliability by determining sensitivity of AQS outputs to underlying parameters, and formulate conditions for robust simulation. Our approach naturally reveals the importance of model symmetries in dictating the robust properties. Finally, to demonstrate the approach, we characterize the robust features of a variety of quantum many-body models.« less

  11. A precondition prover for analogy.

    PubMed

    Bledsoe, W W

    1995-01-01

    We describe here a prover PC (precondition) that normally acts as an ordinary theorem prover, but which returns a 'precondition' when it is unable to prove the given formula. If F is the formula attempted to be proved and PC returns the precondition Q, then (Q-->F) is a theorem (that PC can prove). This prover, PC, uses a proof-plan. In its simplest mode, when there is no proof-plan, it acts like ordinary abduction. We show here how this method can be used to derive certain proofs by analogy. To do this, it uses a proof-plan from a given guiding proof to help construct the proof of a similar theorem, by 'debugging' (automatically) that proof-plan. We show here the analogy proofs of a few simple example theorems and one hard pair, Ex4 and Ex4L. The given proof-plan for Ex4 is used by the system to prove automatically Ex4; and that same proof-plan is then used to prove Ex4L, during which the proof-plan is 'debugged' (automatically). These two examples are similar to two other, more difficult, theorems from the theory of resolution, namely GCR (the ground completeness of resolution) and GCLR (the ground completeness of lock resolution). GCR and GCLR have also been handled, in essence, by this system but not completed in all their details.

  12. Prostacyclin analogs inhibit fibroblast migration.

    PubMed

    Kohyama, Tadashi; Liu, Xiangde; Kim, Hui Jung; Kobayashi, Tetsu; Ertl, Ronald F; Wen, Fu-Qiang; Takizawa, Hajime; Rennard, Stephen I

    2002-08-01

    The controlled accumulation of fibroblasts to sites of inflammation is crucial to effective tissue repair after injury. Either inadequate or excessive accumulation of fibroblasts could result in abnormal tissue function. Prostacyclin (PGI(2)) is a potent mediator in the coagulation and inflammatory processes. The aim of this study was to investigate the effect of PGI(2) on chemotaxis of human fetal lung fibroblasts (HFL-1). Using the blind well chamber technique, we found that the PGI(2) analog carbaprostacyclin (10(-6) M) inhibited HFL-1 chemotaxis to human plasma fibronectin (20 microg/ml) 58.0 +/- 13.2% (P < 0.05) and to platelet-derived growth factor (PDGF)-BB (10 ng/ml) 48.7 +/- 4.6% (P < 0.05). Checkerboard analysis demonstrated that carbaprostacyclin inhibits both directed and undirected migration. The inhibitory effect of the carbaprostacyclin was concentration dependent and blocked by the cAMP-dependent protein kinase (PKA) inhibitor KT-5720, suggesting that a cAMP-PKA pathway may be involved in the process. Two other PGI(2) analogs, ciprostene and dehydro-15-cyclohexyl carbaprostacyclin (both 10(-6) M), significantly inhibited fibroblast migration to fibronectin. In summary, PGI(2) appears to inhibit fibroblast chemotaxis to fibronectin and PDGF-BB. Such an effect may contribute to the regulation of fibroblasts in wound healing and could contribute to the pathogenesis of diseases characterized by abnormal tissue repair remodeling.

  13. Double inflation

    SciTech Connect

    Silk, J.; Turner, M.S.

    1986-04-01

    The Zel'dovich spectrum of adiabatic density perturbations is a generic prediction of inflation. There is increasing evidence that when the spectrum is normalized by observational data on small scales, there is not enough power on large scales to account for the observed large-scale structure in the Universe. Decoupling the spectrum on large and small scales could solve this problem. As a means of decoupling the large and small scales we propose double inflation (i.e., two episodes of inflation). In this scenario the spectrum on large scales is determined by the first episode of inflation and those on small scales by a second episode of inflation. We present three models for such a scenario. By nearly saturating the large angular-scale cosmic microwave anisotropy bound, we can easily account for the observed large-scale structure. We take the perturbations on small scales to be very large, deltarho/rho approx. = 0.1 to 0.01, which results in the production of primordial black holes (PBHs), early formation of structure, reionization of the Universe, and a rich array of astrophysical events. The ..cap omega..-problem is also addressed by our scenario. Allowing the density perturbations produced by the second episode of inflation to be large also lessens the fine-tuning required in the scalar potential and makes reheating much easier. We briefly speculate on the possibility that the second episode of inflation proceeds through the nucleation of bubbles, which today manifest themselves as empty bubbles whose surfaces are covered with galaxies. 37 refs., 1 fig.

  14. Seeing Double

    NASA Astrophysics Data System (ADS)

    Pesic, Peter

    2003-10-01

    The separateness and connection of individuals is perhaps the central question of human life: What, exactly, is my individuality? To what degree is it unique? To what degree can it be shared, and how? To the many philosophical and literary speculations about these topics over time, modern science has added the curious twist of quantum theory, which requires that the elementary particles of which everything consists have no individuality at all. All aspects of chemistry depend on this lack of individuality, as do many branches of physics. From where, then, does our individuality come? In Seeing Double, Peter Pesic invites readers to explore this intriguing set of questions. He draws on literary and historical examples that open the mind (from Homer to Martin Guerre to Kafka), philosophical analyses that have helped to make our thinking and speech more precise, and scientific work that has enabled us to characterize the phenomena of nature. Though he does not try to be all-inclusive, Pesic presents a broad range of ideas, building toward a specific point of view: that the crux of modern quantum theory is its clash with our ordinary concept of individuality. This represents a departure from the usual understanding of quantum theory. Pesic argues that what is bizarre about quantum theory becomes more intelligible as we reconsider what we mean by individuality and identity in ordinary experience. In turn, quantum identity opens a new perspective on us. Peter Pesic is a Tutor and Musician-in-Residence at St. John's College, Santa Fe, New Mexico. He has a Ph.D. in physics from Stanford University.

  15. Double Your Major, Double Your Return?

    ERIC Educational Resources Information Center

    Del Rossi, Alison F.; Hersch, Joni

    2008-01-01

    We use the 2003 National Survey of College Graduates to provide the first estimates of the effect on earnings of having a double major. Overall, double majoring increases earnings by 2.3% relative to having a single major among college graduates without graduate degrees. Most of the gains from having a double major come from choosing fields across…

  16. Fault diagnosis of analog circuits

    NASA Astrophysics Data System (ADS)

    Bandler, J. W.; Salama, A. E.

    1985-08-01

    Theory and algorithms associated with four main categories of modern techniques used to locate faults in analog circuits are presented. These four general approaches are: the fault dictionary (FDA), the parameter identification (PIA), the fault verification (FVA), and the approximation (AA) approaches. The preliminaries and problems associated with the FDA, such as fault dictionary construction, the methods of optimum measurement selection, fault isolation criteria, and efficient methods of fault simulation, are discussed. The PIA techniques that utilize either linear or nonlinear systems of equations for identification of network elements are examined. Description of the FVA includes node-fault diagnosis, branch-fault diagnosis, subnetwork testability conditions, as well as combinatorial techniques, the failure-bound technique, and the network decomposition technique. In the AA, probabilistic methods and optimization-based methods are considered. In addition, the artificial intelligence technique and the different measures of testability are presented. A series of block diagrams is included.

  17. The Young Solar Analogs Project

    NASA Astrophysics Data System (ADS)

    Gray, Richard O.; Saken, J. M.; Corbally, C. J.; Fuller, V.; Kahvaz, Y.; Lambert, R.; Newsome, I.; Seeds, M.

    2013-01-01

    We are carrying out a long-term project of measuring chromospheric activity and brightness variations in 31 young solar analogs (YSAs) using facilities at the Dark Sky Observatory (DSO - Appalachian State University) and the Vatican Advanced Technology Telescope (VATT). These YSAs are solar-type (spectral types F8 - K2) stars with ages ranging from 0.3 - 1.5 Gyr. The goal of this project is to gain better understanding of the magnetic activity of the early Sun, and especially how that activity may have impacted the development of life on the Earth. This project will also yield insights into the space environments experienced by young Earth analogs. We are currently in the 6th year of spectroscopic measurements of these stars: these data include Ca II H & K chromospheric flux measurements, and narrow-band measurements in the photospheric G-band, both obtained with the G/M spectrograph on the DSO 32-inch telescope. We will present evidence of activity cycles in a number of our stars, as well as periods determined from rotational modulation of the spectroscopic indices. The relationship between the Ca II activity index and the G-band index will be explored. NSF support for our project has provided funds for the construction of a robotic photometric telescope to monitor the program stars in a 5-passband system (Strömgren-v, Johnson-Cousins B, V, and R, and a 3-nm wide Hα filter). The robotic telescope has been functional since April 2012 and observes the program stars on every clear night; combined with the Piggy-back telescope attached to the DSO 32-inch, we now have photometric observations on over 130 nights stretching over nearly 2 years. We will examine the relationships between variations in the Ca II H & K index, the G-band index and the photometric bands. This project is supported by the National Science Foundation, grant AST-1109158.

  18. The Young Solar Analogs Project

    NASA Astrophysics Data System (ADS)

    Gray, Richard O.; Saken, J. M.; Corbally, C. J.; Seeds, M. F.; Morrison, S. S.

    2012-01-01

    We are carrying out a long-term project of measuring chromospheric activity and brightness variations in 31 young solar analogs (YSAs) using the Dark Sky Observatory (DSO -- Appalachian State University) 32-inch telescope and the G/M spectrograph. These YSAs are solar-type (spectral types F8 - K2) stars with ages ranging from 0.3 - 1.5 Gyr. The goal of this project is to gain better understanding of the magnetic activity of the early Sun, and especially how that activity may have impacted the development of life on the Earth. This project will also yield insights into the space environments experienced by young Earth analogs. We are currently in our 5th year of obtaining Ca II K & H chromospheric flux measurements, and are beginning to see signs of long-term activity cycles in a number of our stars. In addition, rotational modulation of the chromospheric fluxes is detectable in our data, and we have determined rotational periods for many of our stars. Short timescale increases in the K & H fluxes have been observed in a number of our stars; these events may be related to stellar flares. VATTSpec, a new moderate-resolution spectrograph on the 1.8-m Vatican Telescope in Arizona, has recently become involved with the project. This spectrograph will increase our ability to detect short-term changes in stellar activity on timescales of hours to minutes. We have been monitoring the program stars for one year in a multi-band photometric system consisting of Stromgren-v, and Johnson B, V, and R filters. We will soon add a narrow-band H-alpha filter to the system. Photometry is being carried out with a small piggy-back telescope on the 32-inch, but a robotic photometric telescope is currently being installed at DSO for this purpose. This project is supported by the National Science Foundation.

  19. Priming analogical reasoning with false memories.

    PubMed

    Howe, Mark L; Garner, Sarah R; Threadgold, Emma; Ball, Linden J

    2015-08-01

    Like true memories, false memories are capable of priming answers to insight-based problems. Recent research has attempted to extend this paradigm to more advanced problem-solving tasks, including those involving verbal analogical reasoning. However, these experiments are constrained inasmuch as problem solutions could be generated via spreading activation mechanisms (much like false memories themselves) rather than using complex reasoning processes. In three experiments we examined false memory priming of complex analogical reasoning tasks in the absence of simple semantic associations. In Experiment 1, we demonstrated the robustness of false memory priming in analogical reasoning when backward associative strength among the problem terms was eliminated. In Experiments 2a and 2b, we extended these findings by demonstrating priming on newly created homonym analogies that can only be solved by inhibiting semantic associations within the analogy. Overall, the findings of the present experiments provide evidence that the efficacy of false memory priming extends to complex analogical reasoning problems.

  20. Children's use of analogy during collaborative reasoning.

    PubMed

    Lin, Tzu-Jung; Anderson, Richard C; Hummel, John E; Jadallah, May; Miller, Brian W; Nguyen-Jahiel, Kim; Morris, Joshua A; Kuo, Li-Jen; Kim, Il-Hee; Wu, Xiaoying; Dong, Ting

    2012-01-01

    This microgenetic study examined social influences on children's development of analogical reasoning during peer-led small-group discussions of stories about controversial issues. A total of 277 analogies were identified among 7,215 child turns for speaking during 54 discussions from 18 discussion groups in 6 fourth-grade classrooms (N = 120; age M=10.0, SD=0.6). Use of analogy was found to spread among the children in discussion groups and occur at an accelerating rate, primarily because of the increasing use of novel analogies. Relational analogies with shared surface features triggered purely relational analogies during the next 2 speaking turns, showing a trend of relational shift. These results provide distinctive new evidence for the importance of social interaction in an aspect of cognitive development.

  1. Collective-coupling analysis of spectra of mass-7 isobars: {sup 7}He, {sup 7}Li, {sup 7}Be, and {sup 7}B

    SciTech Connect

    Canton, L.; Pisent, G.; Amos, K.; Karataglidis, S.; Svenne, J. P.; Knijff, D. van der

    2006-12-15

    A nucleon-nucleus interaction model has been applied to ascertain the underlying character of the negative-parity spectra of four isobars of mass-7, from neutron- to proton-emitter drip lines. With a single nuclear potential defined by a simple coupled-channel model, a multichannel algebraic scattering approach (MCAS) has been used to determine the bound and resonant spectra of the four nuclides, of which {sup 7}He and {sup 7}B are particle unstable. Incorporation of Pauli blocking into the model enables a description of all known spin-parity states of the mass-7 isobars. We have also obtained spectra of similar quality by using a large space no-core shell model. Additionally, we have studied {sup 7}Li and {sup 7}Be using a dicluster model. We have found a dicluster-model potential that can reproduce the lowest four states of the two nuclei, as well as the relevant low-energy elastic scattering cross sections. But, with this model, the rest of the energy spectra cannot be obtained.

  2. Extensive Peptide Fractionation and y1 Ion-Based Interference Detection Method for Enabling Accurate Quantification by Isobaric Labeling and Mass Spectrometry.

    PubMed

    Niu, Mingming; Cho, Ji-Hoon; Kodali, Kiran; Pagala, Vishwajeeth; High, Anthony A; Wang, Hong; Wu, Zhiping; Li, Yuxin; Bi, Wenjian; Zhang, Hui; Wang, Xusheng; Zou, Wei; Peng, Junmin

    2017-02-22

    Isobaric labeling quantification by mass spectrometry (MS) has emerged as a powerful technology for multiplexed large-scale protein profiling, but measurement accuracy in complex mixtures is confounded by the interference from coisolated ions, resulting in ratio compression. Here we report that the ratio compression can be essentially resolved by the combination of pre-MS peptide fractionation, MS2-based interference detection, and post-MS computational interference correction. To recapitulate the complexity of biological samples, we pooled tandem mass tag (TMT)-labeled Escherichia coli peptides at 1:3:10 ratios and added in ∼20-fold more rat peptides as background, followed by the analysis of two-dimensional liquid chromatography (LC)-MS/MS. Systematic investigation shows that quantitative interference was impacted by LC fractionation depth, MS isolation window, and peptide loading amount. Exhaustive fractionation (320 × 4 h) can nearly eliminate the interference and achieve results comparable to the MS3-based method. Importantly, the interference in MS2 scans can be estimated by the intensity of contaminated y1 product ions, and we thus developed an algorithm to correct reporter ion ratios of tryptic peptides. Our data indicate that intermediate fractionation (40 × 2 h) and y1 ion-based correction allow accurate and deep TMT profiling of more than 10 000 proteins, which represents a straightforward and affordable strategy in isobaric labeling proteomics.

  3. Microstructural Response During Isothermal and Isobaric Loading of a Precipitation-Strengthened Ni-29.7Ti-20Hf High-Temperature Shape Memory Alloy

    NASA Astrophysics Data System (ADS)

    Benafan, O.; Noebe, R. D.; Padula, S. A.; Vaidyanathan, R.

    2012-12-01

    A stable Ni-rich Ni-29.7Ti-20Hf (at. pct) shape memory alloy, with relatively high transformation temperatures, was shown to exhibit promising properties at lower raw material cost when compared to typical NiTi-X (X = Pt, Pd, Au) high-temperature shape memory alloys (HTSMAs). The excellent dimensional stability and high work output for this alloy were attributed to a coherent, nanometer size precipitate phase observed using transmission electron microscopy. To establish an understanding of the role of these precipitates on the microstructure and ensuing stability of the NiTiHf alloy, a detailed study of the micromechanical and microstructural behaviors was performed. In-situ neutron diffraction at stress and temperature was used to obtain quantitative information on phase-specific internal strain, texture, and phase volume fractions during both isothermal and isobaric testing of the alloy. During isothermal testing, the alloy exhibited low isothermal strains due to limited detwinning, consistent with direct measurements of the bulk texture through neutron diffraction. This limited detwinning was attributed to the pinning of twin and variant boundaries by the dispersion of fine precipitates. During isobaric thermal cycling at 400 MPa, the high work output and near-perfect dimensional stability was attributed to the presence of the precipitates that act as homogeneous sources for the nucleation of martensite throughout the material, while providing resistance to irrecoverable processes such as plastic deformation.

  4. Custom 4-Plex DiLeu Isobaric Labels Enable Relative Quantification of Urinary Proteins in Men with Lower Urinary Tract Symptoms (LUTS).

    PubMed

    Greer, Tyler; Hao, Ling; Nechyporenko, Anatoliy; Lee, Sanghee; Vezina, Chad M; Ricke, Will A; Marker, Paul C; Bjorling, Dale E; Bushman, Wade; Li, Lingjun

    2015-01-01

    The relative quantification of proteins using liquid chromatography mass spectrometry (LC-MS) has allowed researchers to compile lists of potential disease markers. These complex quantitative workflows often include isobaric labeling of enzymatically-produced peptides to analyze their relative abundances across multiple samples in a single LC-MS run. Recent efforts by our lab have provided scientists with cost-effective alternatives to expensive commercial labels. Although the quantitative performance of these dimethyl leucine (DiLeu) labels has been reported using known ratios of complex protein and peptide standards, their potential in large-scale proteomics studies using a clinically relevant system has never been investigated. Our work rectifies this oversight by implementing 4-plex DiLeu to quantify proteins in the urine of aging human males who suffer from lower urinary tract symptoms (LUTS). Protein abundances in 25 LUTS and 15 control patients were compared, revealing that of the 836 proteins quantified, 50 were found to be differentially expressed (>20% change) and statistically significant (p-value <0.05). Gene ontology (GO) analysis of the differentiated proteins showed that many were involved in inflammatory responses and implicated in fibrosis. While confirmation of individual protein abundance changes would be required to verify protein expression, this study represents the first report using the custom isobaric label, 4-plex DiLeu, to quantify protein abundances in a clinically relevant system.

  5. Isobaric Quantification of Cerebrospinal Fluid Amyloid-β Peptides in Alzheimer's Disease: C-Terminal Truncation Relates to Early Measures of Neurodegeneration.

    PubMed

    Rogeberg, Magnus; Almdahl, Ina Selseth; Wettergreen, Marianne; Nilsson, Lars N G; Fladby, Tormod

    2015-11-06

    The amyloid beta (Aβ) peptide is the main constituent of the plaques characteristic of Alzheimer's disease (AD). Measurement of Aβ1-42 in cerebrospinal fluid (CSF) is a valuable marker in AD research, where low levels indicate AD. Although the use of immunoassays measuring Aβ1-38 and Aβ1-40 in addition to Aβ1-42 has increased, quantitative assays of other Aβ peptides remain rarely explored. We recently discovered novel Aβ peptides in CSF using antibodies recognizing the Aβ mid-domain region. Here we have developed a method using both Aβ N-terminal and mid-domain antibodies for immunoprecipitation in combination with isobaric labeling and liquid chromatography-tandem mass spectrometry (LC-MS/MS) for relative quantification of endogenous Aβ peptides in CSF. The developed method was used in a pilot study to produce Aβ peptide profiles from 38 CSF samples. Statistical comparison between CSF samples from 19 AD patients and 19 cognitively healthy controls revealed no significant differences at group level. A significant correlation was found between several larger C-terminally truncated Aβ peptides and protein biomarkers for neuronal damage, particularly prominent in the control group. Comparison of the isobaric quantification with immunoassays measuring Aβ1-38 or Aβ1-40 showed good correlation (r(2) = 0.84 and 0.85, respectively) between the two analysis methods. The developed method could be used to assess disease-modifying therapies directed at Aβ production or degradation.

  6. AnalogExplorer2 – Stereochemistry sensitive graphical analysis of large analog series

    PubMed Central

    Hu, Ye; Zhang, Bijun; Vogt, Martin; Bajorath, Jürgen

    2015-01-01

    AnalogExplorer is a computational methodology for the extraction and organization of series of structural analogs from compound data sets and their graphical analysis. The method is suitable for the analysis of large analog series originating from lead optimization programs. Herein we report AnalogExplorer2 designed to explicitly take stereochemical information during graphical analysis into account and describe a freely available deposition of the original AnalogExplorer program, AnalogExplorer2, and exemplary compound sets to illustrate their use. PMID:26913194

  7. AnalogExplorer2 - Stereochemistry sensitive graphical analysis of large analog series.

    PubMed

    Hu, Ye; Zhang, Bijun; Vogt, Martin; Bajorath, Jürgen

    2015-01-01

    AnalogExplorer is a computational methodology for the extraction and organization of series of structural analogs from compound data sets and their graphical analysis. The method is suitable for the analysis of large analog series originating from lead optimization programs. Herein we report AnalogExplorer2 designed to explicitly take stereochemical information during graphical analysis into account and describe a freely available deposition of the original AnalogExplorer program, AnalogExplorer2, and exemplary compound sets to illustrate their use.

  8. Design and Analysis of Reconfigurable Analog System

    DTIC Science & Technology

    2011-02-01

    34010010" �" �" �" �" �" �" �±" N3 N2 N± P1 P2 P3 * Current sources $RR = 1; *Ramp Rate (slope of the...2008/12/12/31e83bac-500f-4182- acca -4d360295fd9c.pdf, Analog Devices, Analog Dialogue 39-06, June 2005. [15] D. A. Johns, K. Martin "Analog Integrated

  9. Classical Analogs of a Diatomic Chain

    SciTech Connect

    Gutierrez, L.; Diaz-de-Anda, A.; Mendez-Sanchez, R. A.; Morales, A.; Flores, J.; Monsivais, G.

    2010-12-21

    Using one dimensional rods with different configurations classical analogs of quantum mechanical systems frequently used in solid state physics can be obtained. Among this analogs we have recently discussed locally periodic rods which lead to band spectra; the effect of a topological defect, and the Wannier Stark ladders. In this paper, we present an elastic analog of the diatomic chain and show how the acoustical and optical bands emerge, as well of the nature of the wave amplitudes.

  10. Fermilab accelerator control system: Analog monitoring facilities

    SciTech Connect

    Seino, K.; Anderson, L.; Smedinghoff, J.

    1987-10-01

    Thousands of analog signals are monitored in different areas of the Fermilab accelerator complex. For general purposes, analog signals are sent over coaxial or twinaxial cables with varying lengths, collected at fan-in boxes and digitized with 12 bit multiplexed ADCs. For higher resolution requirements, analog signals are digitized at sources and are serially sent to the control system. This paper surveys ADC subsystems that are used with the accelerator control systems and discusses practical problems and solutions, and it describes how analog data are presented on the console system.

  11. Properties of compressible elastica from relativistic analogy.

    PubMed

    Oshri, Oz; Diamant, Haim

    2016-01-21

    Kirchhoff's kinetic analogy relates the deformation of an incompressible elastic rod to the classical dynamics of rigid body rotation. We extend the analogy to compressible filaments and find that the extension is similar to the introduction of relativistic effects into the dynamical system. The extended analogy reveals a surprising symmetry in the deformations of compressible elastica. In addition, we use known results for the buckling of compressible elastica to derive the explicit solution for the motion of a relativistic nonlinear pendulum. We discuss cases where the extended Kirchhoff analogy may be useful for the study of other soft matter systems.

  12. Robust hyperchaotic synchronization via analog transmission line

    NASA Astrophysics Data System (ADS)

    Sadoudi, S.; Tanougast, C.

    2016-02-01

    In this paper, a novel experimental chaotic synchronization technique via analog transmission is discussed. We demonstrate through Field-Programmable Gate Array (FPGA) implementation design the robust synchronization of two embedded hyperchaotic Lorenz generators interconnected with an analog transmission line. The basic idea of this work consists in combining a numerical generation of chaos and transmitting it with an analog signal. The numerical chaos allows to overcome the callback parameter mismatch problem and the analog transmission offers robust data security. As application, this technique can be applied to all families of chaotic systems including time-delayed chaotic systems.

  13. Real World: Analog Testing in Extreme Environments

    NASA Image and Video Library

    See how NASA uses analog testing to simulate space exploration. Explore extreme environments like the Aquarius underwater laboratory in Key Largo, Florida. Find out how scientists use mathematical ...

  14. Effect of a bispidinone analog on mitochondria‑mediated apoptosis in HeLa cells.

    PubMed

    Yi, Myeongjin; Parthiban, Paramasivam; Hwang, Jiyoung; Zhang, Xin; Jeong, Hyunjin; Park, Dong Ho; Kim, Dong-Kyoo

    2014-01-01

    The present study was carried out to investigate the effect of 2,4,6,8-tetraaryl-3,7-diazabicyclo[3.3.1]nonan-9-one (bispidinone) analogs on the in vitro growth of human cervical carcinoma (HeLa) cells. A series of 11 bispidinone analogs was synthesized with substituents, e.g., fluoro/methyl/ethyl/isopropyl/thiomethyl/methoxy groups, at various positions. These compounds were synthesized to identify which substituent and position induced the strongest cytotoxic effect in cancer cells. Among these synthetics, analog 9, which contains methoxy groups, had the most significant cytotoxic effect on HeLa cells, and its IC50 value was less than 13 µM. A WST-8 assay also showed that analog 9 inhibited the proliferation of HeLa cells. By using DNA content analysis, we found that analog 9 induced sub-G1 and G1 phase arrest in a time-dependent manner. A [3H]-thymidine incorporation assay suggested that analog 9 inhibited DNA replication in HeLa cells. On performing light microscopy, morphological changes such as cellular shrinkage and disruption, which are apoptotic features, were observed in HeLa cells. Annexin V/propidium iodide double staining and rhodamine-123 staining showed that analog 9 induced apoptosis and disrupted the intracellular mitochondrial membrane potential in HeLa cells. The western blot analysis results suggested that analog 9 induced mitochondria-mediated apoptosis. In addition, we have shown that analog 9 may play a role in the Fas signaling apoptotic pathway.

  15. Expert analogy use in a naturalistic setting

    PubMed Central

    Kretz, Donald R.; Krawczyk, Daniel C.

    2014-01-01

    The use of analogy is an important component of human cognition. The type of analogy we produce and communicate depends heavily on a number of factors, such as the setting, the level of domain expertise present, and the speaker's goal or intent. In this observational study, we recorded economics experts during scientific discussion and examined the categorical distance and structural depth of the analogies they produced. We also sought to characterize the purpose of the analogies that were generated. Our results supported previous conclusions about the infrequency of superficial similarity in subject-generated analogs, but also showed that distance and depth characteristics were more evenly balanced than in previous observational studies. This finding was likely due to the nature of the goals of the participants, as well as the broader nature of their expertise. An analysis of analogical purpose indicated that the generation of concrete source examples of more general target concepts was most prevalent. We also noted frequent instances of analogies intended to form visual images of source concepts. Other common purposes for analogies were the addition of colorful speech, inclusion (i.e., subsumption) of a target into a source concept, or differentiation between source and target concepts. We found no association between depth and either of the other two characteristics, but our findings suggest a relationship between purpose and distance; i.e., that visual imagery typically entailed an outside-domain source whereas exemplification was most frequently accomplished using within-domain analogies. Overall, we observed a rich and diverse set of spontaneously produced analogical comparisons. The high degree of expertise within the observed group along with the richly comparative nature of the economics discipline likely contributed to this analogical abundance. PMID:25505437

  16. Extensions of the concept of suction analogy to prediction of vortex lift effect

    NASA Technical Reports Server (NTRS)

    Lan, C. E.

    1986-01-01

    Flow field data for a double delta wing at low speed were used to determine the location of a vortex action point. The result was found to be consistent with what was determined for a delta wing. In supersonic flow, the action point location was determined empirically. For a wing with rounded leading edges, an assumption for initial vortex separation was shown to be equivalent to initial leading edge bubble separation for airfoils. A theoretical formulation by the section analogy to determine the delayed vortex separation on a cambered wing with rounded leading edges was presented. The method of suction analogy was further shown to be applicable to predicting the body vortex lift.

  17. Digital and analog chemical evolution.

    PubMed

    Goodwin, Jay T; Mehta, Anil K; Lynn, David G

    2012-12-18

    Living matter is the most elaborate, elegant, and complex hierarchical material known and is consequently the natural target for an ever-expanding scientific and technological effort to unlock and deconvolute its marvelous forms and functions. Our current understanding suggests that biological materials are derived from a bottom-up process, a spontaneous emergence of molecular networks in the course of chemical evolution. Polymer cooperation, so beautifully manifested in the ribosome, appeared in these dynamic networks, and the special physicochemical properties of the nucleic and amino acid polymers made possible the critical threshold for the emergence of extant cellular life. These properties include the precise and geometrically discrete hydrogen bonding patterns that dominate the complementary interactions of nucleic acid base-pairing that guide replication and ensure replication fidelity. In contrast, complex and highly context-dependent sets of intra- and intermolecular interactions guide protein folding. These diverse interactions allow the more analog environmental chemical potential fluctuations to dictate conformational template-directed propagation. When these two different strategies converged in the remarkable synergistic ribonucleoprotein that is the ribosome, this resulting molecular digital-to-analog converter achieved the capacity for both persistent information storage and adaptive responses to an ever-changing environment. The ancestral chemical networks that preceded the Central Dogma of Earth's biology must reflect the dynamic chemical evolutionary landscapes that allowed for selection, propagation, and diversification and ultimately the demarcation and specialization of function that modern biopolymers manifest. Not only should modern biopolymers contain molecular fossils of this earlier age, but it should be possible to use this information to reinvent these dynamic functional networks. In this Account, we review the first dynamic network

  18. Children's Use of Analogy during Collaborative Reasoning

    ERIC Educational Resources Information Center

    Lin, Tzu-Jung; Anderson, Richard C.; Hummel, John E.; Jadallah, May; Miller, Brian W.; Nguyen-Jahiel, Kim; Morris, Joshua A.; Kuo, Li-Jen; Kim, Il-Hee; Wu, Xiaoying; Dong, Ting

    2012-01-01

    This microgenetic study examined social influences on children's development of analogical reasoning during peer-led small-group discussions of stories about controversial issues. A total of 277 analogies were identified among 7,215 child turns for speaking during 54 discussions from 18 discussion groups in 6 fourth-grade classrooms (N = 120; age…

  19. The Pennies-as-Electrons Analogy

    ERIC Educational Resources Information Center

    Ashmann, Scott

    2009-01-01

    Everyday experiences familiarize students with the ways in which electricity is used, but often the underlying concepts remain a mystery. Teachers often use analogies to help students relate the flow of electrons to other common systems, but many times these analogies are incomplete and lead to more student misconceptions. However, the "pass the…

  20. Piperazine-based nucleic acid analogs

    DOEpatents

    Schmidt, Jurgen; Silks, Louis A.; Michalczyk, Ryszard

    2005-01-11

    A novel nucleoside analog is disclosed which comprises a piperazine ring in the place of the ring ribose or deoxyribose sugar. Monomers utilizing a broad variety of nucleobases are disclosed, as well as oligomers comprising the monomers disclosed herein linked by a variety of linkages, including amide, phosphonamide, and sulfonamide linkages. A method of synthesizing the nucleoside analogs is also disclosed.

  1. Analogical Processes and College Developmental Reading

    ERIC Educational Resources Information Center

    Paulson, Eric J.

    2014-01-01

    Although a solid body of research concerning the role of analogies in reading processes has emerged at a variety of age groups and reading proficiencies, few of those studies have focused on analogy use by readers enrolled in college developmental reading courses. The current study explores whether 232 students enrolled in mandatory (by placement…

  2. Mathematical Analogs and the Teaching of Fractions.

    ERIC Educational Resources Information Center

    Charles, Kathy; Nason, Rod; Cooper, Tom

    The literature has noted that some mathematical analogs are more effective than others for the teaching of fractions. This study aimed to evaluate the efficacy of seven mathematical analogs commonly used in the teaching of the partitive quotient fraction construct. A sample of twelve purposively selected Year Three children were presented with…

  3. Understanding the Development of Analogical Reasoning Ability.

    ERIC Educational Resources Information Center

    Goldman, Susan R.; Bisanz, Jeffrey

    This paper takes the position that theories about individual differences in childhood and theories about cognitive development both would be enhanced if the two lines of research were integrated. The heuristic value of this position is illustrated in the context of analogical reasoning tasks. A general model of analogy solution and potential…

  4. Rotanone analogs: method of preparation and use

    DOEpatents

    VanBrocklin, Henry F; O& #x27; Neil, James P; Gibbs, Andrew R; Erathodiyil, Nandanan

    2013-10-08

    The present invention provides rotenone analogs and methods of making and using them. Labeled with single photon and positron emitting isotopes, the rotenone analogs of the present invention are useful in, for example, clinical imaging applications as tracers to measure cardiac blood flow and detect regions of ischemia.

  5. A Mechanical Analogy for the Photoelectric Effect

    ERIC Educational Resources Information Center

    Kovacevic, Milan S.; Djordjevich, Alexandar

    2006-01-01

    Analogy is a potent tool in the teacher's repertoire. It has been particularly well recognized in the teaching of science. However, careful planning is required for its effective application to prevent documented drawbacks when analogies are stretched too far. Befitting the occasion of the World Year of Physics commemorating Albert Einstein's 1905…

  6. 38 CFR 4.20 - Analogous ratings.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Analogous ratings. 4.20 Section 4.20 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS SCHEDULE FOR RATING DISABILITIES General Policy in Rating § 4.20 Analogous ratings. When an unlisted condition is encountered it...

  7. A Mechanical Analogy for the Photoelectric Effect

    ERIC Educational Resources Information Center

    Kovacevic, Milan S.; Djordjevich, Alexandar

    2006-01-01

    Analogy is a potent tool in the teacher's repertoire. It has been particularly well recognized in the teaching of science. However, careful planning is required for its effective application to prevent documented drawbacks when analogies are stretched too far. Befitting the occasion of the World Year of Physics commemorating Albert Einstein's 1905…

  8. Analogical Reasoning in Restructuring Scientific Knowledge.

    ERIC Educational Resources Information Center

    Mason, Lucia; Sorzio, Paolo

    1996-01-01

    Presents the results of an experiment that evaluated the efficiency of analogy in the conceptual restructuring of a science topic. The experiment involved a fifth-grade class studying water and heat flow. Discovered that analogy can act as an effective trigger for restructuring knowledge. (MJP)

  9. Structure Mapping in Analogy and Similarity.

    ERIC Educational Resources Information Center

    Gentner, Dedre; Markman, Arthur B.

    1997-01-01

    It is suggested that both similarity and analogy involve a process of structural alignment and mapping. The structure mapping process is described as it has been worked out for analogy, and this view is then extended to similarity and used to generate new predictions. (SLD)

  10. The Multidimensionality of Verbal Analogy Items

    ERIC Educational Resources Information Center

    Ullstadius, Eva; Carlstedt, Berit; Gustafsson, Jan-Eric

    2008-01-01

    The influence of general and verbal ability on each of 72 verbal analogy test items were investigated with new factor analytical techniques. The analogy items together with the Computerized Swedish Enlistment Battery (CAT-SEB) were given randomly to two samples of 18-year-old male conscripts (n = 8566 and n = 5289). Thirty-two of the 72 items had…

  11. The Pennies-as-Electrons Analogy

    ERIC Educational Resources Information Center

    Ashmann, Scott

    2009-01-01

    Everyday experiences familiarize students with the ways in which electricity is used, but often the underlying concepts remain a mystery. Teachers often use analogies to help students relate the flow of electrons to other common systems, but many times these analogies are incomplete and lead to more student misconceptions. However, the "pass the…

  12. Antibacterial and Antibiofilm Activities of Makaluvamine Analogs

    PubMed Central

    Nijampatnam, Bhavitavya; Nadkarni, Dwayaja H.; Wu, Hui; Velu, Sadanandan E.

    2014-01-01

    Streptococcus mutans is a key etiological agent in the formation of dental caries. The major virulence factor is its ability to form biofilms. Inhibition of S. mutans biofilms offers therapeutic prospects for the treatment and the prevention of dental caries. In this study, 14 analogs of makaluvamine, a marine alkaloid, were evaluated for their antibacterial activity against S. mutans and for their ability to inhibit S. mutans biofilm formation. All analogs contained the tricyclic pyrroloiminoquinone core of makaluvamines. The structural variations of the analogs are on the amino substituents at the 7-position of the ring and the inclusion of a tosyl group on the pyrrole ring N of the makaluvamine core. The makaluvamine analogs displayed biofilm inhibition with IC50 values ranging from 0.4 μM to 88 μM. Further, the observed bactericidal activity of the majority of the analogs was found to be consistent with the anti-biofilm activity, leading to the conclusion that the anti-biofilm activity of these analogs stems from their ability to kill S. mutans. However, three of the most potent N-tosyl analogs showed biofilm IC50 values at least an order of magnitude lower than that of bactericidal activity, indicating that the biofilm activity of these analogs is more selective and perhaps independent of bactericidal activity. PMID:25767719

  13. Use of Analogy in Computer Language Acquisition.

    ERIC Educational Resources Information Center

    Pohl, Heidi L.; Nutter, Jane Terry

    1985-01-01

    Subjects in a study of analogic reasoning use in learning a computer language read text describing an invented LISP dialect and then solved problems and described language constructs. Five of six factors studied indicating use of analogy with a familiar computer language showed statistically significant results, supporting the hypothesis.…

  14. The Multidimensionality of Verbal Analogy Items

    ERIC Educational Resources Information Center

    Ullstadius, Eva; Carlstedt, Berit; Gustafsson, Jan-Eric

    2008-01-01

    The influence of general and verbal ability on each of 72 verbal analogy test items were investigated with new factor analytical techniques. The analogy items together with the Computerized Swedish Enlistment Battery (CAT-SEB) were given randomly to two samples of 18-year-old male conscripts (n = 8566 and n = 5289). Thirty-two of the 72 items had…

  15. Verbal Analogical Reasoning in Children and Adolescents.

    ERIC Educational Resources Information Center

    Nippold, Marilyn A.

    1986-01-01

    Verbal analogical reasoning tasks are described as potentially valuable in the assessment and management of subtle linguistic defects less easily detected by standardized language tests. Semantic and structural factors that should be considered in the development of verbal analogies as test items are cited, as well as adaptations for nonreaders.…

  16. Understanding the Development of Analogical Reasoning Ability.

    ERIC Educational Resources Information Center

    Goldman, Susan R.; Bisanz, Jeffrey

    This paper takes the position that theories about individual differences in childhood and theories about cognitive development both would be enhanced if the two lines of research were integrated. The heuristic value of this position is illustrated in the context of analogical reasoning tasks. A general model of analogy solution and potential…

  17. Response Generation Norms for Verbal Analogies.

    ERIC Educational Resources Information Center

    Ingram, Albert; Pellegrino, James W.

    Normative data were collected for the generation of responses to 150 incomplete verbal analogies. Two types of normative data are provided: (a) the probabilities associated with each response produced for each analogy base and (b) the probabilities that initial responses represented the appropriate semantic relationship, with a division of…

  18. Student-Generated Analogies in Biology.

    ERIC Educational Resources Information Center

    Middleton, James L.

    1991-01-01

    Discusses the advantages of and strategies in having students create analogies to facilitate learning biology. Presents a vocabulary worksheet to facilitate analogy creation and describes its use. The author discusses the use of instructional strategies including forced associations, metaphorical sketches, mnemonics, and association memorization.…

  19. Young Children's Analogical Reasoning in Science Domains

    ERIC Educational Resources Information Center

    Haglund, Jesper; Jeppsson, Fredrik; Andersson, Johanna

    2012-01-01

    This exploratory study in a classroom setting investigates first graders' (age 7-8 years, N = 25) ability to perform analogical reasoning and create their own analogies for two irreversible natural phenomena: mixing and heat transfer. We found that the children who contributed actively to a full-class discussion were consistently successful at…

  20. An Analog Computer for Electronic Engineering Education

    ERIC Educational Resources Information Center

    Fitch, A. L.; Iu, H. H. C.; Lu, D. D. C.

    2011-01-01

    This paper describes a compact analog computer and proposes its use in electronic engineering teaching laboratories to develop student understanding of applications in analog electronics, electronic components, engineering mathematics, control engineering, safe laboratory and workshop practices, circuit construction, testing, and maintenance. The…

  1. Young Children's Analogical Reasoning in Science Domains

    ERIC Educational Resources Information Center

    Haglund, Jesper; Jeppsson, Fredrik; Andersson, Johanna

    2012-01-01

    This exploratory study in a classroom setting investigates first graders' (age 7-8 years, N = 25) ability to perform analogical reasoning and create their own analogies for two irreversible natural phenomena: mixing and heat transfer. We found that the children who contributed actively to a full-class discussion were consistently successful at…

  2. An Analog Computer for Electronic Engineering Education

    ERIC Educational Resources Information Center

    Fitch, A. L.; Iu, H. H. C.; Lu, D. D. C.

    2011-01-01

    This paper describes a compact analog computer and proposes its use in electronic engineering teaching laboratories to develop student understanding of applications in analog electronics, electronic components, engineering mathematics, control engineering, safe laboratory and workshop practices, circuit construction, testing, and maintenance. The…

  3. Novel Analog For Muscle Deconditioning

    NASA Technical Reports Server (NTRS)

    Ploutz-Snyder, Lori; Ryder, Jeff; Buxton, Roxanne; Redd. Elizabeth; Scott-Pandorf, Melissa; Hackney, Kyle; Fiedler, James; Ploutz-Snyder, Robert; Bloomberg, Jacob

    2011-01-01

    Existing models (such as bed rest) of muscle deconditioning are cumbersome and expensive. We propose a new model utilizing a weighted suit to manipulate strength, power, or endurance (function) relative to body weight (BW). Methods: 20 subjects performed 7 occupational astronaut tasks while wearing a suit weighted with 0-120% of BW. Models of the full relationship between muscle function/BW and task completion time were developed using fractional polynomial regression and verified by the addition of pre-and postflightastronaut performance data for the same tasks. Splineregression was used to identify muscle function thresholds below which task performance was impaired. Results: Thresholds of performance decline were identified for each task. Seated egress & walk (most difficult task) showed thresholds of leg press (LP) isometric peak force/BW of 18 N/kg, LP power/BW of 18 W/kg, LP work/BW of 79 J/kg, isokineticknee extension (KE)/BW of 6 Nm/kg, and KE torque/BW of 1.9 Nm/kg.Conclusions: Laboratory manipulation of relative strength has promise as an appropriate analog for spaceflight-induced loss of muscle function, for predicting occupational task performance and establishing operationally relevant strength thresholds.

  4. Novel Analog For Muscle Deconditioning

    NASA Technical Reports Server (NTRS)

    Ploutz-Snyder, Lori; Ryder, Jeff; Buxton, Roxanne; Redd, Elizabeth; Scott-Pandorf, Melissa; Hackney, Kyle; Fiedler, James; Bloomberg, Jacob

    2010-01-01

    Existing models of muscle deconditioning are cumbersome and expensive (ex: bedrest). We propose a new model utilizing a weighted suit to manipulate strength, power or endurance (function) relative to body weight (BW). Methods: 20 subjects performed 7 occupational astronaut tasks while wearing a suit weighted with 0-120% of BW. Models of the full relationship between muscle function/BW and task completion time were developed using fractional polynomial regression and verified by the addition of pre- and post-flight astronaut performance data using the same tasks. Spline regression was used to identify muscle function thresholds below which task performance was impaired. Results: Thresholds of performance decline were identified for each task. Seated egress & walk (most difficult task) showed thresholds of: leg press (LP) isometric peak force/BW of 18 N/kg, LP power/BW of 18 W/kg, LP work/ BW of 79 J/kg, knee extension (KE) isokinetic/BW of 6 Nm/Kg and KE torque/BW of 1.9 Nm/kg. Conclusions: Laboratory manipulation of strength / BW has promise as an appropriate analog for spaceflight-induced loss of muscle function for predicting occupational task performance and establishing operationally relevant exercise targets.

  5. Solar System Analog; WMO Statement

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    Scientists searching for extra-solar planets have discovered the closest known analog to our own Solar System. A planet with a mass about twice that of Jupiter is in a near-circular orbit of the star HD70642, a team of astronomers from Australia, the United Kingdom, and the United States announced on 3 July at a conference in Paris on extra-solar planets.The planet measures about three-fifths the size of Jupiter, circles its star about every six years, and is in an orbit equivalent to being about halfway between Mars and Jupiter if it were located in our Solar System, according to the astronomers. The star is about 90 light years away from Earth in the constellation Puppis.Public concern about a spate of well-publicized, extreme weather events around the world this year has prompted the World Meteorological Organization to issue a statement that, as global temperatures continues to rise due to climate change, the number and intensity of extreme events might increase. The July 2 statement is based on scientific assessments by the Intergovernmental Panel on Climate Change and others, rather than on any new studies, according to Ken Davidson, director orf WMO's World Climate Program Department. The statement cites record high termperatures so far this summer in southern France and in Switzerland, an abnormally high number of tornadoes in the U.S. in May, and particularly heavy rains from tropical cyclones in Sri Lanka.

  6. Investigation of Celestial Solid Analogs

    NASA Technical Reports Server (NTRS)

    Sievers, A. J.

    2003-01-01

    Our far infrared studies of both hydrophobic and hydrophilic aerogel grains have demonstrated that the mm and sub-mm wave absorption produced by the fundamental two level systems (TLS) mechanism represents a more significant contribution for these open grain structures than for bulk amorphous silicate grains. We found that the region with the anomalous temperature dependence of the spectral index due to the TLS excitations can extend in a fluffy material up to 80 per cm, which is well beyond its typical upper limit for bulk glasses. Currently there is no theoretical explanation for this surprising result. The effects of reduced dimensionality on the optical properties of carbonaceous grains have been studied with a systematic investigation of carbon aerogels. This spectroscopic approach has permitted a more reliable determination of the single grain mass normalized absorption coefficient based on the experimentally determined characteristics of the fluffy material rather than on first principles calculations involving the bulk properties of the substance. Our finding is that the electrical connectivity of the material is the main factor affecting its far infrared absorption coefficient. Another one of the main constituents of the interstellar dust, amorphous ice, has been investigated in the mm-wave region both in the high (HDA) and low (LDA) density amorphous phases and as a function of impurities. We found that doping either phase with ionic (LiCl) or molecular (methanol) impurities decreases the difference in the mm-wave absorption coefficient between the HDA and LDA ice phases so that the HDA spectrum can be used as an analog for impure ice absorption in the far infrared spectral region.

  7. Analog regulation of metabolic demand

    PubMed Central

    2011-01-01

    Background The 3D structure of the chromosome of the model organism Escherichia coli is one key component of its gene regulatory machinery. This type of regulation mediated by topological transitions of the chromosomal DNA can be thought of as an analog control, complementing the digital control, i.e. the network of regulation mediated by dedicated transcription factors. It is known that alterations in the superhelical density of chromosomal DNA lead to a rich pattern of differential expressed genes. Using a network approach, we analyze these expression changes for wild type E. coli and mutants lacking nucleoid associated proteins (NAPs) from a metabolic and transcriptional regulatory network perspective. Results We find a significantly higher correspondence between gene expression and metabolism for the wild type expression changes compared to mutants in NAPs, indicating that supercoiling induces meaningful metabolic adjustments. As soon as the underlying regulatory machinery is impeded (as for the NAP mutants), this coherence between expression changes and the metabolic network is substantially reduced. This effect is even more pronounced, when we compute a wild type metabolic flux distribution using flux balance analysis and restrict our analysis to active reactions. Furthermore, we are able to show that the regulatory control exhibited by DNA supercoiling is not mediated by the transcriptional regulatory network (TRN), as the consistency of the expression changes with the TRN logic of activation and suppression is strongly reduced in the wild type in comparison to the mutants. Conclusions So far, the rich patterns of gene expression changes induced by alterations of the superhelical density of chromosomal DNA have been difficult to interpret. Here we characterize the effective networks formed by supercoiling-induced gene expression changes mapped onto reconstructions of E. coli's metabolic and transcriptional regulatory network. Our results show that DNA

  8. Namibian Analogs To Titan Dunes

    NASA Astrophysics Data System (ADS)

    Wall, Stephen D.; Lopes, R.; Kirk, R.; Stofan, E.; Farr, T.; Van der Ploeg, P.; Lorenz, R.; Radebaugh, J.

    2009-09-01

    Titan's equatorial dunes, observed in Cassini SAR, have been described as longitudinal, similar to longitudinal dunes in the Namib sand sea in southern Africa. Their "Y” junctions and the way they divert around topography are used as evidence of equatorial wind flow direction. In two instances of such diversion they exhibit overlying or crosshatched patterns in two distinct directions that have been interpreted as a transition to transverse dunes. Here we describe field observations of the Namibian dunes and these comparisons, we present images of the dunes from terrestrial SAR missions, and we discuss implications to both the Titan dunes and the wind regime that created them. Selected portions of the Namibian dunes resemble Titan's dunes in peak-to-peak distance and length. They are morphologically similar to Titan, and specific superficial analogs are common, but they also differ. For example, when Titan dunes encounter topography they either terminate abruptly, "climb” the upslope, or divert around; only the latter behavior is seen in remote sensing images of Namibia. Namib linear dunes do transition to transverse as they divert, but at considerably smaller wavelength, while at Titan the wavelengths are of the same scale. Crosshatching of similar-wavelength dunes does occur in Namibia, but not near obstacles. Many additional aeolian features that are seen at Namibia such as star dunes, serpentine ridges and scours have not been detected on Titan, although they might be below the Cassini SAR's 300-m resolution. These similarities and differences allow us to explore mechanisms of Titan dune formation, in some cases giving us clues as to what larger scale evidence to look for in SAR images. Viewed at similar resolution, they provide interesting comparisons with the Titan dunes, both in likeness and differences. A part of this work was carried out at JPL under contract with NASA.

  9. Mechatronics by Analogy and Application to Legged Locomotion

    NASA Astrophysics Data System (ADS)

    Ragusila, Victor

    A new design methodology for mechatronic systems, dubbed as Mechatronics by Analogy (MbA), is introduced and applied to designing a leg mechanism. The new methodology argues that by establishing a similarity relation between a complex system and a number of simpler models it is possible to design the former using the analysis and synthesis means developed for the latter. The methodology provides a framework for concurrent engineering of complex systems while maintaining the transparency of the system behaviour through making formal analogies between the system and those with more tractable dynamics. The application of the MbA methodology to the design of a monopod robot leg, called the Linkage Leg, is also studied. A series of simulations show that the dynamic behaviour of the Linkage Leg is similar to that of a combination of a double pendulum and a spring-loaded inverted pendulum, based on which the system kinematic, dynamic, and control parameters can be designed concurrently. The first stage of Mechatronics by Analogy is a method of extracting significant features of system dynamics through simpler models. The goal is to determine a set of simpler mechanisms with similar dynamic behaviour to that of the original system in various phases of its motion. A modular bond-graph representation of the system is determined, and subsequently simplified using two simplification algorithms. The first algorithm determines the relevant dynamic elements of the system for each phase of motion, and the second algorithm finds the simple mechanism described by the remaining dynamic elements. In addition to greatly simplifying the controller for the system, using simpler mechanisms with similar behaviour provides a greater insight into the dynamics of the system. This is seen in the second stage of the new methodology, which concurrently optimizes the simpler mechanisms together with a control system based on their dynamics. Once the optimal configuration of the simpler system is

  10. First online multireflection time-of-flight mass measurements of isobar chains produced by fusion-evaporation reactions: Toward identification of superheavy elements via mass spectroscopy

    NASA Astrophysics Data System (ADS)

    Schury, P.; Wada, M.; Ito, Y.; Kaji, D.; Arai, F.; MacCormick, M.; Murray, I.; Haba, H.; Jeong, S.; Kimura, S.; Koura, H.; Miyatake, H.; Morimoto, K.; Morita, K.; Ozawa, A.; Rosenbusch, M.; Reponen, M.; Söderström, P.-A.; Takamine, A.; Tanaka, T.; Wollnik, H.

    2017-01-01

    Using a multireflection time-of-flight mass spectrograph located after a gas cell coupled with the gas-filled recoil ion separator GARIS-II, the masses of several α -decaying heavy nuclei were directly and precisely measured. The nuclei were produced via fusion-evaporation reactions and separated from projectilelike and targetlike particles using GARIS-II before being stopped in a helium-filled gas cell. Time-of-flight spectra for three isobar chains, 204Fr-204Rn-204At-204Po , 205Fr-205Rn-205At-205Po-205Bi , and 206Fr-206Rn-206At , were observed. Precision atomic mass values were determined for Fr-206204, Rn,205204, and At,205204. Identifications of 205Bi, Po,205204, 206Rn, and 206At were made with N ≲10 detected ions, representing the next step toward use of mass spectrometry to identify exceedingly low-yield species such as superheavy element ions.

  11. Structure of even-even A=138 isobars and the yrast spectra of semi-magic Sn isotopes above the {sup 132}Sn core

    SciTech Connect

    Sarkar, S.; Sarkar, M. Saha

    2008-08-15

    Large basis untruncated shell model (SM) calculations have been done for the A=138 neutron-rich nuclei in the {pi}(gdsh)+{nu}(hfpi) valence space above the {sup 132}Sn core using two (1+2) -body nuclear Hamiltonians, viz., realistic CWG and empirical SMPN. Calculated binding energies, excitation spectra, and wave function structures are compared for even-even A=138 isobars for which experimental data are available. The nearly vibrational states in {sup 138}Te, Xe, and the B(E2;2{sup +}{yields}0{sup +}) value in {sup 138}Xe are excellently reproduced by both the interactions. For {sup 138}Ba, the calculated spectra and the B(E2;2{sup +}{yields}0{sup +}) value also agree very well with the experimental results. But the two theoretical results differ dramatically for {sup 138}Sn, a nucleus on the r-process path. CWG predicts nearly constant energies of 2{sub 1}{sup +} states for the even-even Sn isotopes above the {sup 132}Sn core, normally expected for semi-magic nuclei. But SMPN predicts a remarkable new feature: decreasing E(2{sub 1}{sup +}) energies with increasing neutron number. The predicted energies for the Sn isotopes fit in the systematics for the E(2{sub 1}{sup +}) energies of their isotones with Z>50. Despite their differences, both interactions predict the 6{sub 1}{sup +} state to be a {approx_equal}0.3 {mu}s isomer in {sup 138}Sn. Calculated magnetic dipole moments and electric quadrupole moments of the states in these isobars are compared with the experimental data wherever available. The appearance of deformation and evolution of collectivity in nuclei in this valence space are discussed.

  12. Novel and cost-effective 6-plex isobaric tagging reagent, DiART, is effective for identification and relative quantification of complex protein mixtures using PQD fragmentation.

    PubMed

    Ramsubramaniam, Nikhil; Tao, Feng; Li, Shuwei; Marten, Mark R

    2013-09-01

    Deuterium isobaric Amine Reactive Tag (DiART) reagents facilitate relative quantification during proteomic analysis in a functionally similar manner to commercially available isobaric tag for relative and absolute quantitation (iTRAQ) and tandem mass tag (TMT) reagents. In contrast to iTRAQ and TMT, DiART reagents incorporate deuterium isotopes which significantly reduce the number of required synthesis steps and hence have potential to significantly reduce reagent production cost. We examined the capability of DiART for performing quantitative proteomic experiments using a linear ion-trap mass spectrometer with Pulsed Q Dissociation (PQD) fragmentation. Using a synthetic peptide tagged with DiART reagent, we observed a precise mass shift of 144.79 Da on the triply charged precursor ion, which shows complete derivatization of the N-terminus and ε-amino group of lysine. A DiART tagged tryptic digest of bovine serum albumin showed a sequence coverage of 57.99% which was very comparable to that showed by iTRAQ, 54.77%. Furthermore, a ten protein mixture tagged with DiART reagents and mixed in 1:1:1:1:1:1 exhibited < 15% error, whereas a linear trend (slope of 1.085) was observed when tagged proteins were mixed in the ratio 2:1:2:4:10:14 and plotted against theoretical ratios. Finally, when complex cell-wall protein mixtures from the model fungus A. nidulans were tagged with DiART reagents and mixed in different ratios, they exhibited similar trends. We conclude that DiART reagents are capable of performing quantitative proteomic experiments using PQD on a linear ion trap mass spectrometer. Copyright © 2013 John Wiley & Sons, Ltd.

  13. Analysis of the isobaric compounds propanol, acetic acid and methyl formate in humid air and breath by selected ion flow tube mass spectrometry, SIFT-MS

    NASA Astrophysics Data System (ADS)

    Pysanenko, Andriy; Spanel, Patrik; Smith, David

    2009-08-01

    Numerous analyses of exhaled breath using selected ion flow tube mass spectrometry, SIFT-MS, over the last few years have revealed the presence of volatile compounds with molecular weight 60 and the concern has been to identify which of the isobaric compounds from the set of 1-propanol, 2-propanol, acetic acid and methyl formate are present in human breath. The problem is compounded by the formation of hydrates of the characteristic primary product ions of the reactions of the H3O+ and NO+ precursor ions with these compounds, this being particularly efficient for humid samples such as exhaled breath. Thus, the resulting product ion spectra are complex and choices have to be made as to which of the characteristic product ions and their hydrates can best be used for the quantitative analyses. To facilitate this choice for the particular problem of identifying and quantifying the four aforementioned isobaric compounds, a study has been made of the ion chemistry of H3O+ and NO+ with the two propanol isomers, acetic acid and methyl formate for increasing sample humidity up to that of exhaled breath, which is about 6% by volume. The problems involved in the separate analysis of propanol have been met and solved by previous SIFT-MS studies and now the present study has revealed how acetic acid and methyl formate can be separately identified in a humid mixture using NO+ precursor ions only. Following this work, the kinetics database entries for the SIFT-MS analyses of these compounds in breath have been constructed and the analysis of the exhaled breath of five healthy volunteers showed that, in addition to the propanol isomers, acetic acid was present at levels typically within the range from 30 to 60 parts-per-billion by volume and that methyl formate was not present above the limit of detection.

  14. Sulfonium Ion Derivatization, Isobaric Stable Isotope Labeling and Data Dependent CID- and ETD-MS/MS for Enhanced Phosphopeptide Quantitation, Identification and Phosphorylation Site Characterization

    PubMed Central

    Lu, Yali; Zhou, Xiao; Stemmer, Paul M.; Reid, Gavin E.

    2014-01-01

    An amine specific peptide derivatization strategy involving the use of novel isobaric stable isotope encoded ‘fixed charge’ sulfonium ion reagents, coupled with an analysis strategy employing capillary HPLC, ESI-MS, and automated data dependent ion trap CID-MS/MS, -MS3, and/or ETD-MS/MS, has been developed for the improved quantitative analysis of protein phosphorylation, and for identification and characterization of their site(s) of modification. Derivatization of 50 synthetic phosphopeptides with S,S′-dimethylthiobutanoylhydroxysuccinimide ester iodide (DMBNHS), followed by analysis using capillary HPLC-ESI-MS, yielded an average 2.5-fold increase in ionization efficiencies and a significant increase in the presence and/or abundance of higher charge state precursor ions compared to the non-derivatized phosphopeptides. Notably, 44% of the phosphopeptides (22 of 50) in their underivatized states yielded precursor ions whose maximum charge states corresponded to +2, while only 8% (4 of 50) remained at this maximum charge state following DMBNHS derivatization. Quantitative analysis was achieved by measuring the abundances of the diagnostic product ions corresponding to the neutral losses of ‘light’ (S(CH3)2) and ‘heavy’ (S(CD3)2) dimethylsulfide exclusively formed upon CID-MS/MS of isobaric stable isotope labeled forms of the DMBNHS derivatized phosphopeptides. Under these conditions, the phosphate group stayed intact. Access for a greater number of peptides to provide enhanced phosphopeptide sequence identification and phosphorylation site characterization was achieved via automated data-dependent CID-MS3 or ETD-MS/MS analysis due to the formation of the higher charge state precursor ions. Importantly, improved sequence coverage was observed using ETD-MS/MS following introduction of the sulfonium ion fixed charge, but with no detrimental effects on ETD fragmentation efficiency. PMID:21952753

  15. Isobaric Tags for Relative and Absolute Quantitation (iTRAQ)-Based Comparative Proteome Analysis of the Response of Ramie under Drought Stress

    PubMed Central

    An, Xia; Zhang, Jingyu; Dai, Lunjin; Deng, Gang; Liao, Yiwen; Liu, Lijun; Wang, Bo; Peng, Dingxiang

    2016-01-01

    In this study, we conducted the first isobaric tags for relative and absolute quantitation (isobaric tags for relative and absolute quantitation (iTRAQ))-based comparative proteomic analysis of ramie plantlets after 0 (minor drought stress), 24 (moderate drought stress), and 72 h (severe drought stress) of treatment with 15% (w/v) poly (ethylene glycol)6000 (PEG6000) to simulate drought stress. In our study, the association analysis of proteins and transcript expression revealed 1244 and 968 associated proteins identified in leaves and roots, respectively. L1, L2, and L3 are leaf samples which were harvested at 0, 24, and 72 h after being treated with 15% PEG6000, respectively. Among those treatment groups, a total of 118, 216, and 433 unique proteins were identified as differentially expressed during L1 vs. L2, L2 vs. L3, and L1 vs. L3, respectively. R1, R2, and R3 are root samples which were harvested at 0, 24, and 72 h after being treated with 15% PEG6000, respectively. Among those treatment groups,a total of 124, 27, and 240 unique proteins were identified as differentially expressed during R1 vs. R2, R2 vs. R3, and R1 vs. R3, respectively. Bioinformatics analysis indicated that glycolysis/gluconeogenesis was significantly upregulated in roots in response to drought stress. This enhancement may result in more glycolytically generated adenosine triphosphate (ATP) in roots to adapt to adverse environmental conditions. To obtain complementary information related to iTRAQ data, the mRNA levels of 12 proteins related to glycolysis/gluconeogenesis in leaves and 7 in roots were further analyzed by qPCR. Most of their expression levels were higher in R3 than R1 and R2, suggesting that these compounds may promote drought tolerance by modulating the production of available energy. PMID:27689998

  16. Fostering Multilateral Involvement in Analog Research

    NASA Technical Reports Server (NTRS)

    Cromwell, Ronita L.

    2015-01-01

    International collaboration in space flight research is an effective means for conducting investigations and utilizing limited resources to the fullest extent. Through these multilateral collaborations mutual research questions can be investigated and resources contributed by each international partner to maximize the scientific benefits to all parties. Recently the international partners embraced this approach to initiate collaborations in ground-based space flight analog environments. In 2011, the International Analog Research Working Group was established, and later named the International Human Space Flight Analog Research Coordination Group (HANA). Among the goals of this working group are to 1) establish a framework to coordinate research campaigns, as appropriate, to minimize duplication of effort and enhance synergy; 2) define what analogs are best to use for collaborative interests; and 3) facilitate interaction between discipline experts in order to have the full benefit of international expertise. To accomplish these goals, HANA is currently engaged in developing international research campaigns in ground-based analogs. Plans are being made for an international solicitation for proposals to address research of common interest to all international partners. This solicitation with identify an analog environment that will best accommodate the types of investigations requested. Once selected, studies will be integrated into a campaign and implemented at the analog site. Through these combined efforts, research beneficial to all partners will be conducted efficiently to further address human risks of space exploration.

  17. Observed Methods for Generating Analogies in Scientific Problem Solving. Revised.

    ERIC Educational Resources Information Center

    Clement, John

    Evidence from video tapes of experts thinking aloud and using analogies in scientific problem solving is presented. Four processes appear to be important in using an analogy: (1) generating the analogy; (2) establishing confidence in the validity of the analogy relation; (3) understanding the analogous case; and (4) applying findings to the…

  18. Analogies: Explanatory Tools in Web-Based Science Instruction

    ERIC Educational Resources Information Center

    Glynn, Shawn M.; Taasoobshirazi, Gita; Fowler, Shawn

    2007-01-01

    This article helps designers of Web-based science instruction construct analogies that are as effective as those used in classrooms by exemplary science teachers. First, the authors explain what analogies are, how analogies foster learning, and what form analogies should take. Second, they discuss science teachers' use of analogies. Third, they…

  19. Analogies: Explanatory Tools in Web-Based Science Instruction

    ERIC Educational Resources Information Center

    Glynn, Shawn M.; Taasoobshirazi, Gita; Fowler, Shawn

    2007-01-01

    This article helps designers of Web-based science instruction construct analogies that are as effective as those used in classrooms by exemplary science teachers. First, the authors explain what analogies are, how analogies foster learning, and what form analogies should take. Second, they discuss science teachers' use of analogies. Third, they…

  20. Analog detection for cavity lifetime spectroscopy

    DOEpatents

    Zare, Richard N.; Harb, Charles C.; Paldus, Barbara A.; Spence, Thomas G.

    2001-05-15

    An analog detection system for determining a ring-down rate or decay rate 1/.tau. of an exponentially decaying ring-down beam issuing from a lifetime or ring-down cavity during a ring-down phase. Alternatively, the analog detection system determines a build-up rate of an exponentially growing beam issuing from the cavity during a ring-up phase. The analog system can be employed in continuous wave cavity ring-down spectroscopy (CW CRDS) and pulsed CRDS (P CRDS) arrangements utilizing any type of ring-down cavity including ring-cavities and linear cavities.

  1. Analog detection for cavity lifetime spectroscopy

    DOEpatents

    Zare, Richard N.; Harb, Charles C.; Paldus, Barbara A.; Spence, Thomas G.

    2003-01-01

    An analog detection system for determining a ring-down rate or decay rate 1/.tau. of an exponentially decaying ring-down beam issuing from a lifetime or ring-down cavity during a ring-down phase. Alternatively, the analog detection system determines a build-up rate of an exponentially growing beam issuing from the cavity during a ring-up phase. The analog system can be employed in continuous wave cavity ring-down spectroscopy (CW CRDS) and pulsed CRDS (P CRDS) arrangements utilizing any type of ring-down cavity including ring-cavities and linear cavities.

  2. Programmable Analog-To-Digital Converter

    NASA Technical Reports Server (NTRS)

    Kist, Edward H., Jr.

    1993-01-01

    High-speed analog-to-digital converter with programmable voltage steps that can be changed during operation. Allows concentration of converter resolution over specific portion of waveform. Particularly useful in digitizing wind-shear radar and lidar return signals, in digital oscilloscopes, and other applications in which desirable to increase digital resolution over specific area of waveform while accepting lower resolution over rest of waveform. Effective increase in dynamic range achieved without increase in number of analog-to-digital converter bits. Enabling faster analog-to-digital conversion.

  3. A CMOS analog front-end chip for amperometric electrochemical sensors

    NASA Astrophysics Data System (ADS)

    Zhichao, Li; Yuntao, Liu; Min, Chen; Jingbo, Xiao; Jie, Chen

    2015-07-01

    This paper reports a complimentary metal-oxide-semiconductor (CMOS) analog front-end chip for amperometric electrochemical sensors. The chip includes a digital configuration circuit, which can communicate with an external microcontroller by employing an I2C interface bus, and thus is highly programmable. Digital correlative double samples technique and an incremental sigma-delta analog to digital converter (Σ-Δ ADC) are employed to achieve a new proposed system architecture with double samples. The chip has been fabricated in a standard 0.18-μm CMOS process with high-precision and high-linearity performance occupying an area of 1.3 × 1.9 mm2. Sample solutions with various phosphate concentrations have been detected with a step concentration of 0.01 mg/L. Project supported by the National Key Basic Research and Development Project (No. 2015CB352103).

  4. A MEMS-Based Power-Scalable Hearing Aid Analog Front End.

    PubMed

    Deligoz, I; Naqvi, S R; Copani, T; Kiaei, S; Bakkaloglu, B; Sang-Soo Je; Junseok Chae

    2011-06-01

    A dual-channel directional digital hearing aid front end using microelectromechanical-systems microphones, and an adaptive-power analog processing signal chain are presented. The analog front end consists of a double differential amplifier-based capacitance-to-voltage conversion circuit, 40-dB variable gain amplifier (VGA) and a power-scalable continuous time sigma delta analog-to-digital converter (ADC), with 68-dB signal-to-noise ratio dissipating 67 μ W from a 1.2-V supply. The MEMS microphones are fabricated using a standard surface micromachining technology. The VGA and power-scalable ADC are fabricated on a 0.25-μ m complementary metal-oxide semciconductor TSMC process.

  5. A double-double/double-single computation package

    SciTech Connect

    Bailey, David H.

    2004-12-01

    The DDFUNIDSFUN software permits a new or existing Fortran-90 program to utilize double-double precision (approx. 31 digits) or double-single precision (approx. 14 digits) arithmetic. Double-double precision is required by a rapidly expandirtg body of scientific computations in physics and mathematics, for which the conventional 64-bit IEEE computer arithmetic (about 16 decimal digit accuracy) is not sufficient. Double-single precision permits users of systems that do not have hardware 64-bit IEEE arithmetic (such as some game systems) to perform arithmetic at a precision nearly as high as that of systems that do. Both packages run significantly faster Than using multiple precision or arbitrary precision software for this purpose. The package includes an extensive set of low-level routines to perform high-precision arithmetic, including routines to calculate various algebraic and transcendental functions, such as square roots, sin, ccc, exp, log and others. In addition, the package includes high-level translation facilities, so that Fortran programs can utilize these facilities by making only a few changes to conventional Fortran programs. In most cases, the only changes that are required are to change the type statements of variables that one wishes to be treated as multiple precision, plus a few other minor changes. The DDFUN package is similar in functionality to the double-double part of the GD package, which was previously written at LBNL. However, the DDFUN package is written exclusively in Fortran-90, thus avoidIng difficulties that some users experience when using GD, which includes both Fortran-90 and C++ code.

  6. High Resolution Double-Focusing Isotope Ratio Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Radke, J.; Deerberg, M.; Hilkert, A.; Schlüter, H.-J.; Schwieters, J.

    2012-04-01

    In recent years isotope ratio mass spectrometry has extended to the capability of quantifying very small isotope signatures related with low abundances and simultaneously detecting molecular masses such as isotopomers and isotopologues containing clumped isotopes. Some of those applications are limited by molecular interferences like different gas molecules with the same nominal mass, e.g. Ar/O2, adducts of the same molecule or of different molecules, and very small isotope abundances. The Thermo Scientific MAT 253 ULTRA is the next generation of high precision gas isotope ratio mass spectrometry, which combines a 10 KV gas ionization source (Thermo Scientific MAT 253) with a double focusing multi-collector mass analyzer (Thermo Scientific Neptune) and reduces those limitations by measuring isotope ratios on a larger dynamic range with high precision. Small ion beam requirements and high sensitivity are achieved by signal-to-noise improvements through enhanced ion beam amplification in faraday cups and ion counters. Interfering backgrounds, e.g. interfering isotopologues or isobaric ions of contaminants, are dramatically decreased by a dynamic range increase combined with high evacuation leading to undisturbed ion transmission through the double-focusing analyser. Furthermore, automated gain calibration for mathematical baseline corrections, switchable detector arrays, ion source control, analyser focusing and full data export is controlled under Isodat data control. New reference/sample strategies are under investigation besides incorporation of the continuous-flow technique and its versatile inlet devices. We are presenting first results and applications of the MAT 253 Ultra.

  7. Analogy between language and biology: a functional approach.

    PubMed

    Victorri, Bernard

    2007-03-01

    We adopt here a functional approach to the classical comparison between language and biology. We first parallel events which have a functional signification in each domain, by matching the utterance of a sentence with the release of a protein. The meaning of a protein is then defined by analogy as "the constant contribution of the biochemical material composing the protein to the effects produced by any release of the protein". The proteome of an organism corresponds to an I-language (the idiolect of an individual), and the proteome of a species is equivalent to an E-language (a language in the common sense). Proteins and sentences are both characterized by a complex hierarchical structure, but the language property of 'double articulation' has no equivalent in the biological domain in this analogy, contrary to previous proposals centered on the genetic code. Besides, the same intimate relation between structure and meaning holds in both cases (syntactic structure for sentences and three-dimensional conformation for proteins). An important disanalogy comes from the combinatorial power of language which is not shared by the proteome as a whole, but it must be noted that the immune system possesses interesting properties in this respect. Regarding evolutionary aspects, the analogy still works to a certain extent. Languages and proteomes can be both considered as belonging to a general class of systems, that we call "productive self-reproductive systems", characterized by the presence of two dynamics: a fast dynamics in an external domain where functional events occur (productive aspect), and a slow dynamics responsible for the evolution of the system itself, driven by the feed-back of events related to the reproduction process.

  8. A CMOS APS arrays with TDI in analog voltage domain

    NASA Astrophysics Data System (ADS)

    Ji, Cheng; Chen, Yongping

    2016-01-01

    CMOS APS sensors suffer from the SNR reduction caused by the decrease in integration time, especially under the case of low light condition and high relative velocity between objects and sensors. In this paper, a new APS circuits architecture by which TDI function is implemented in the analog voltage domain is proposed to overcome this problem. Time delay integration operation is a straightforward method comes from good old CCD sensors in which signals are added in charge packages with low noise. In this design TDI is mainly achieved by the switch capacitor accumulators and corresponding timing sequences implemented by digital logic on chip. The main noise source especially come from analog sample hold capacitors and OPA are analyzed. The offsets and FPNs are reduced by auto-zero operation and double difference sampling. A 16x128 3T TDI pixel arrays has been taped out by CSMC 0.5 um technology. And finally from the simulation results, a 10dB/dec SNR increase in terms of TDI level has been achieved under low light condition.

  9. VHDL Implementation of Sigma-Delta Analog To Digital Converter

    NASA Astrophysics Data System (ADS)

    Chavan, R. N.; Chougule, D. G.

    2010-11-01

    Sigma-Delta modulation techniques provide a range of opportunities in a signal processing system for both increasing performance and data path optimization along the silicon area axis in the design space. One of the most challenging tasks in Analog to Digital Converter (ADC) design is to adapt the circuitry to ever new CMOS process technology. For digital circuits the number of gates per square mm app. doubles per chip generation. Integration of analog parts in newer deep submicron technologies is much more tough and additionally complicated because the usable voltage ranges are decreasing with every new integration step. This paper shows an approach which only uses 2 resistors and 1 capacitor which are located outside a pure digital chip. So all integration advantages of pure digital chips are preserved, there is no design effort for a new chip generation and the ADC also can be used for FPGAs. Resolutions of up to 16 bit are achievable. Sample rates in the 1 MHz region are feasible so that the approach is also useful for ADCs for xDSL technologies.

  10. It never dies: assessing the Nazi analogy in bioethics.

    PubMed

    Campbell, Courtney S

    1992-01-01

    ... As should be evident from the foregoing analysis, I have significant reservations about the moral utility of the Nazi analogy in debates over bioethics issues. Nevertheless, I am unable to dismiss its force entirely. I want to suggest that the real threat to the moral and human values expressed by the analogy will come not from responsibly formulated and clearly articulated proposals that undergo debate and scrutiny in the public forum, and whose practical impact in a democratic society is limited by institutional review and procedural safeguards. My concern instead is with the psychology of moral distancing, in which moral conscience is compartmentalized from vocational interests, such as the pursuit of scientific knowledge through biomedical research. It is the kind of psychology that Robert Jay Lifton has referrred to as "doubling: the division of the self into two functioning wholes, so that a part-self acts as an entire self," and which Lifton believes enabled the transformation of physicians from healers to killers in Nazi Germany....

  11. Inhibition studies of sulfonamide-containing folate analogs in yeast.

    PubMed

    Patel, Onisha; Satchell, Jacqueline; Baell, Jonathan; Fernley, Ross; Coloe, Peter; Macreadie, Ian

    2003-01-01

    In the folate biosynthetic pathway, sulfa drugs (sulfonamides and sulfones) compete with the natural substrate, para-aminobenzoate (pABA) causing depletion of dihydrofolate (DHF) and subsequent growth inhibition. The sulfa drugs condense with 2-amino-4-hydroxy-6-hydroxymethyl-7,8 dihydropteridine pyrophosphate (DHPPP) forming sulfa-dihydropteroate (sulfa-DHP). Here evidence is presented using yeast that such dihydropteroate (DHP) analogs are inhibitory through competition with DHF. Two folate synthesis mutants, with respective dihydrofolate synthase (DHFS) and dihydropteroate synthase (DHPS) deletions and requiring DHF for growth were exposed to sulfa drugs. The DHFS knockout mutant was inhibited, but the DHPS knockout mutant that was incapable of forming sulfa-DHP was insensitive. Such sulfa-DHP compounds were chemically synthesized and shown to be inhibitory in vivo by competing with DHF, but in vitro assays with double the concentration of the sulfa-DHP to DHF showed no inhibition of dihydrofolate reductase (DHFR). Sequence analysis of resistant mutants obtained in the presence of sulfa drugs showed no changes in DHFR, or DHPS, unlike previously found antifolate-resistant mutants. The diamino derivatives, which are precursors of the sulfa-DHP, were found to be DHFR inhibitors. These results suggest that a new class of drugs, based on DHP analogs, could be investigated.

  12. High-performance transmission in analog photonic links

    NASA Astrophysics Data System (ADS)

    Chen, Zhiyu; Yan, Lianshan; Jiang, Hengyun; Ye, Jia; Pan, Wei; Luo, Bin; Zou, Xihua

    2013-12-01

    Analog photonic link (APL) has been considered to be a promising technique due to the low insertion loss, broad bandwidth and immunity to electromagnetic interference. It is essential for many microwave systems, such as avionics, modern electronic warfare, and wireless communication systems. However, polarization effect, chromatic dispersion (CD), fiber Kerr effect and RF nonlinearity are four main problems in APL. All of them degrade the performance of the link. Therefore, APL needs to be optimized according to the different requirements in various applications. In this paper, we firstly establish a propagation model and provide the general expressions for the analog signal in photonic link based on coupled-mode theory and the small-signal analysis. Such model can describe the interaction of polarization effect, CD and nonlinearity. We also investigate the noise figure (NF) and spurious-free dynamic range (SFDR) in dispersive nonlinear link based on the proposed model. Subsequently, we review and introduce different compensation schemes for these impairments, such as CD compensation based on double sideband (DSB) modulation, and simultaneous compensation for CD and nonlinearity by employing a phase modulator (PM). After compensations, the SFDR of the link can be improved greatly. In addition, recent experimental results show that APL might be a supporting technique for the 4G or higher speed optical-wireless communication systems in near future.

  13. Computer Analogies: Teaching Molecular Biology and Ecology.

    ERIC Educational Resources Information Center

    Rice, Stanley; McArthur, John

    2002-01-01

    Suggests that computer science analogies can aid the understanding of gene expression, including the storage of genetic information on chromosomes. Presents a matrix of biology and computer science concepts. (DDR)

  14. Analog Computer Laboratory with Biological Examples.

    ERIC Educational Resources Information Center

    Strebel, Donald E.

    1979-01-01

    The use of biological examples in teaching applications of the analog computer is discussed and several examples from mathematical ecology, enzyme kinetics, and tracer dynamics are described. (Author/GA)

  15. Review of field-programmable analog arrays

    NASA Astrophysics Data System (ADS)

    Gulak, Glen; D'Mello, Dean R.

    1996-10-01

    The drive towards shorter design cycles for analog integrated circuits has given impetus to several developments in the area of field-programmable analog arrays (FPAAs). Various approaches have been taken in implementing topological and parametric programmability of analog circuits. Recent extensions of this work have married FPAAs to their digital counterparts (FPGAs) along with data conversion interfaces, to form field-programmable mixed signal arrays (FPMAs). This survey paper reviews work to data in the area of programmable analog and mixed signal circuits. The body of work reviewed includes university and industrial research, commercial products and patents. A time-line of important achievements in the area is drawn and the status of various activities is summarized.

  16. An Earth Analog to Mars Yellowknife Bay

    NASA Image and Video Library

    2013-03-12

    A sampling pit exposing clay-bearing lake sediments, deposited in a basaltic basin in southern Australia -- a modern terrestrial analog to the Yellowknife Bay area that NASA Curiosity rover is exploring.

  17. Analog Computer Laboratory with Biological Examples.

    ERIC Educational Resources Information Center

    Strebel, Donald E.

    1979-01-01

    The use of biological examples in teaching applications of the analog computer is discussed and several examples from mathematical ecology, enzyme kinetics, and tracer dynamics are described. (Author/GA)

  18. CMOS analog switches for adaptive filters

    NASA Technical Reports Server (NTRS)

    Dixon, C. E.

    1980-01-01

    Adaptive active low-pass filters incorporate CMOS (Complimentary Metal-Oxide Semiconductor) analog switches (such as 4066 switch) that reduce variation in switch resistance when filter is switched to any selected transfer function.

  19. An Electrical Analog Computer for Poets

    ERIC Educational Resources Information Center

    Bruels, Mark C.

    1972-01-01

    Nonphysics majors are presented with a direct current experiment beyond Ohms law and series and parallel laws. This involves construction of an analog computer from common rheostats and student-assembled voltmeters. (Author/TS)

  20. The Analog (Computer) As a Physiology Adjunct.

    ERIC Educational Resources Information Center

    Stewart, Peter A.

    1979-01-01

    Defines and discusses the analog computer and its use in a physiology laboratory. Includes two examples: (1) The Respiratory Control Function and (2) CO-Two Control in the Respiratory System. Presents diagrams and mathematical models. (MA)