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Sample records for gamow-teller strength function

  1. Gamow-Teller strength distributions for neutron-rich nitrogen, oxygen and fluorine isotopes

    NASA Astrophysics Data System (ADS)

    Zhang, Yu-Mei

    2016-08-01

    Gamow-Teller transition properties for neutron-rich nitrogen, oxygen and fluorine isotopes are studied in integrated energy. The structures of these nuclei are described by means of nuclear shell model with the WBT interaction in the p-sd shell space. Calculations of the Gamow-Teller strength distribution reproduce the experimental data reasonably in the low-energy region. For the dripline nucleus 24O, a super Gamow-Teller transition to a single state at excitation energy of 14.72 MeV in 24F is predicted. β-decay half-lives for these nuclei are calculated and compared with the available experimental data.

  2. β+ Gamow-Teller Transition Strengths from Ti46 and Stellar Electron-Capture Rates

    NASA Astrophysics Data System (ADS)

    Noji, S.; Zegers, R. G. T.; Austin, Sam M.; Baugher, T.; Bazin, D.; Brown, B. A.; Campbell, C. M.; Cole, A. L.; Doster, H. J.; Gade, A.; Guess, C. J.; Gupta, S.; Hitt, G. W.; Langer, C.; Lipschutz, S.; Lunderberg, E.; Meharchand, R.; Meisel, Z.; Perdikakis, G.; Pereira, J.; Recchia, F.; Schatz, H.; Scott, M.; Stroberg, S. R.; Sullivan, C.; Valdez, L.; Walz, C.; Weisshaar, D.; Williams, S. J.; Wimmer, K.

    2014-06-01

    The Gamow-Teller strength in the β+ direction to Sc46 was extracted via the Ti46(t ,He3+γ) reaction at 115 MeV /u. The γ-ray coincidences served to precisely measure the very weak Gamow-Teller transition to a final state at 991 keV. Although this transition is weak, it is crucial for accurately estimating electron-capture rates in astrophysical scenarios with relatively low stellar densities and temperatures, such as presupernova stellar evolution. Shell-model calculations with different effective interactions in the pf shell-model space do not reproduce the experimental Gamow-Teller strengths, which is likely due to sd-shell admixtures. Calculations in the quasiparticle random phase approximation that are often used in astrophysical simulations also fail to reproduce the experimental Gamow-Teller strength distribution, leading to strongly overestimated electron-capture rates. Because reliable theoretical predictions of Gamow-Teller strengths are important for providing astrophysical electron-capture reaction rates for a broad set of nuclei in the lower pf shell, we conclude that further theoretical improvements are required to match astrophysical needs.

  3. β+ Gamow-Teller transition strengths from 46Ti and stellar electron-capture rates.

    PubMed

    Noji, S; Zegers, R G T; Austin, Sam M; Baugher, T; Bazin, D; Brown, B A; Campbell, C M; Cole, A L; Doster, H J; Gade, A; Guess, C J; Gupta, S; Hitt, G W; Langer, C; Lipschutz, S; Lunderberg, E; Meharchand, R; Meisel, Z; Perdikakis, G; Pereira, J; Recchia, F; Schatz, H; Scott, M; Stroberg, S R; Sullivan, C; Valdez, L; Walz, C; Weisshaar, D; Williams, S J; Wimmer, K

    2014-06-27

    The Gamow-Teller strength in the β(+) direction to (46)Sc was extracted via the (46)Ti(t,(3)He + γ) reaction at 115  MeV/u. The γ-ray coincidences served to precisely measure the very weak Gamow-Teller transition to a final state at 991 keV. Although this transition is weak, it is crucial for accurately estimating electron-capture rates in astrophysical scenarios with relatively low stellar densities and temperatures, such as presupernova stellar evolution. Shell-model calculations with different effective interactions in the pf shell-model space do not reproduce the experimental Gamow-Teller strengths, which is likely due to sd-shell admixtures. Calculations in the quasiparticle random phase approximation that are often used in astrophysical simulations also fail to reproduce the experimental Gamow-Teller strength distribution, leading to strongly overestimated electron-capture rates. Because reliable theoretical predictions of Gamow-Teller strengths are important for providing astrophysical electron-capture reaction rates for a broad set of nuclei in the lower pf shell, we conclude that further theoretical improvements are required to match astrophysical needs. PMID:25014806

  4. β+ Gamow-Teller transition strengths from 46Ti and stellar electron-capture rates.

    PubMed

    Noji, S; Zegers, R G T; Austin, Sam M; Baugher, T; Bazin, D; Brown, B A; Campbell, C M; Cole, A L; Doster, H J; Gade, A; Guess, C J; Gupta, S; Hitt, G W; Langer, C; Lipschutz, S; Lunderberg, E; Meharchand, R; Meisel, Z; Perdikakis, G; Pereira, J; Recchia, F; Schatz, H; Scott, M; Stroberg, S R; Sullivan, C; Valdez, L; Walz, C; Weisshaar, D; Williams, S J; Wimmer, K

    2014-06-27

    The Gamow-Teller strength in the β(+) direction to (46)Sc was extracted via the (46)Ti(t,(3)He + γ) reaction at 115  MeV/u. The γ-ray coincidences served to precisely measure the very weak Gamow-Teller transition to a final state at 991 keV. Although this transition is weak, it is crucial for accurately estimating electron-capture rates in astrophysical scenarios with relatively low stellar densities and temperatures, such as presupernova stellar evolution. Shell-model calculations with different effective interactions in the pf shell-model space do not reproduce the experimental Gamow-Teller strengths, which is likely due to sd-shell admixtures. Calculations in the quasiparticle random phase approximation that are often used in astrophysical simulations also fail to reproduce the experimental Gamow-Teller strength distribution, leading to strongly overestimated electron-capture rates. Because reliable theoretical predictions of Gamow-Teller strengths are important for providing astrophysical electron-capture reaction rates for a broad set of nuclei in the lower pf shell, we conclude that further theoretical improvements are required to match astrophysical needs.

  5. Gamow-Teller Strength in the A=14 Multiplet: A Challenge to the Shell Model

    SciTech Connect

    Negret, A; Adachi, T; Barrett, B R; Baumer, C; den Berg, A v; Berg, G; von Brentano, P; Frekers, D; De Frenne, D; Fujita, H; Fujita, K; Fujita, Y; Grewe, E; Haefner, P; Harakeh, M; Hatanaka, K; Heyde, K; Hunyadi, M; Jacobs, E; Kalmykov, Y; Korff, A; Nakanishi, K; Navratil, P; von Neumann-Cosel, P; Popescu, L; Rakers, S; Richter, A; Ryezayeva, N; Sakemi, Y; Schevchenko, A; Shimbara, Y; Shimizu, Y; Tameshige, Y; Tamii, A; Uchida, M; Vary, J; Wortche, H; Yosoi, M; Zamick, L

    2006-08-07

    A new experimental approach to the famous problem of the anomalously slow Gamow-Teller (GT) transitions in the {beta} decay of the A = 14 multiplet is presented. The GT strength distributions to excited states in {sup 14}C and {sup 14}O was studied in high-resolution (d,{sup 2}He) and ({sup 3}He,t) charge-exchange reactions on {sup 14}N. No-core shell-model (NCSM) calculations capable of reproducing the suppression of the {beta} decays predict a selective excitation of J{sup {pi}} = 2{sup +} states. The experimental confirmation represents a validation of the assumptions about the underlying structure of the {sup 14}N ground state wave function. However, the fragmentation of the GT strength over three 2{sup +} final states remains a fundamental issue not explained by the present NCSM using a 6 {h_bar}{omega} model space, suggesting possibly the need to include cluster structure in these light nuclei in a consistent way.

  6. Role of momentum transfer in the quenching of the Gamow-Teller strength

    SciTech Connect

    Marketin, T.; Martinez-Pinedo, G.; Paar, N.; Vretenar, D.

    2012-10-20

    A recent analysis of (p,n) and (n,p) reaction data from {sup 90}Zr was performed recently, where a significant amount of Gamow-Teller strength was found above the resonance, an energy region previously unreachable by experimental setups. The extracted strengths in the {beta}{sub -} and the {beta}{sub +} channel indicate that approximately 10% of the total strength necessary to satisfy the model independent Ikeda sum rule is missing. One possible source of this discrepancy is the treatment of the isovector spin monopole (IVSM) mode of excitation which has been found to occurr at high excitation energies. Employing the relativistic Hartree-Bogoliubov (RHB) model and the protonneutron relativistic quasiparticle random phase approximation (pn-RQRPA) to calculate the nuclear response, we explore the contribution of the IVSM mode to the total L= 0 strength and apply our results to the available data.

  7. Gamow-Teller and dipole strength in the 208Pb(n,p) reaction

    NASA Astrophysics Data System (ADS)

    Raywood, K. J.; Long, S. A.; Spicer, B. M.

    1997-02-01

    Earlier data on the 208Pb(n,p) 208Ti reaction at 198 MeV has been analysed using the multipole decomposition technique, and the contributions to the spectra from L = 0 and 1 transitions determined. The L = 0 cross section has been found to be smaller than values given by the calculations of MacFarlane [3] for Gamow-Teller transitions, using three different forms for the population of single particle states about the Fermi energy. Comparison is made with GT-strength values obtained from a more recent mean field calculation of these populations, and with an older nuclear structure calculation of properties of the lead nuclei. The L = 1 strength distribution is also reported.

  8. Gamow-Teller strength distributions and neutrino energy loss rates due to chromium isotopes in stellar matter

    NASA Astrophysics Data System (ADS)

    Nabi, Jameel-Un; Shehzadi, Ramoona; Fayaz, Muhammad

    2016-03-01

    Gamow-Teller transitions in isotopes of chromium play a consequential role in the presupernova evolution of massive stars. β-decay and electron capture rates on chromium isotopes significantly affect the time rate of change of lepton fraction (dot{Ye}). Fine-tuning of this parameter is one of the key for simulating a successful supernova explosion. The (anti)neutrinos produced as a result of electron capture and β-decay are transparent to stellar matter during presupernova phases. They carry away energy and this result in cooling the stellar core. In this paper we present the calculations of Gamow-Teller strength distributions and (anti)neutrino energy loss rates due to weak interactions on chromium isotopes of astrophysical importance. We compare our results with measured data and previous calculations wherever available.

  9. Gamow-Teller strength distributions and stellar weak-interaction rates for ^{76}Ge and ^{82}Se using the deformed pn-QRPA model

    NASA Astrophysics Data System (ADS)

    Nabi, Jameel-Un; Ishfaq, Mavra

    2016-07-01

    We calculate Gamow-Teller strength distributions for β β-decay nuclei ^{76}Ge and ^{82}Se using the deformed pn-QRPA model. We use a deformed Nilsson basis and consider pairing correlations within the deformed BCS theory. Ground state correlations and two-particle and two-hole mixing states were included in our pn-QRPA model. Our calculated strength distributions were compared with experimental data and previous calculation. The total Gamow-Teller strength and centroid placement calculated in our model compares well with the measured value. We calculate β-decay and positron capture rates on ^{76}Ge and ^{82}Se in supernovae environments and compare them to those obtained from experimental data and previous calculation. Our study shows that positron capture rates command the total weak rates at high stellar temperatures. We also calculate energy rates of β-delayed neutrons and their emission probabilities.

  10. Gamow-Teller strengths in {sup 24}Na using the {sup 24}Mg(t,{sup 3}He) reaction at 115A MeV

    SciTech Connect

    Howard, M. E.; Smith, E. E.; Zegers, R. G. T.; Brown, B. A.; Gade, A.; Hitt, G. W.; Austin, Sam M.; Cole, A. L.; Galaviz, D.; Bazin, D.; Famiano, M.; Matos, M.; Shimbara, Y.; Davids, B.; Fujita, Y.; Reitzner, S. D.; Schradin, L. J.; Samanta, C.; Simenel, C.

    2008-10-15

    Gamow-Teller transitions from {sup 24}Mg to {sup 24}Na were studied via the (t,{sup 3}He) reaction at 115A MeV using a secondary triton beam produced via fast fragmentation of 150A MeV {sup 16}O ions. Compared to previous (t,{sup 3}He) experiments at this energy that employed a primary {alpha} beam, the secondary beam intensity is improved by about a factor of five. Despite the large emittance of the secondary beam, an excitation-energy resolution of {approx}200 keV is achieved. A good correspondence is found between the extracted Gamow-Teller strength distribution and those available from other charge-exchange probes. Theoretical calculations using the newly developed USDA and USDB sd-shell model interactions reproduce the data well.

  11. Gamow-Teller Strength in the Exotic Odd-Odd Nuclei {sup 138}La and {sup 180}Ta and Its Relevance for Neutrino Nucleosynthesis

    SciTech Connect

    Byelikov, A.; Kalmykov, Y.; Neumann-Cosel, P. von; Richter, A.; Shevchenko, A.; Adachi, T.; Fujita, Y.; Shimbara, Y.; Fujita, H.; Fujita, K.; Hatanaka, K.; Kawase, K.; Nakanishi, K.; Sakamoto, N.; Sakemi, Y.; Shimizu, Y.; Tameshige, Y.; Tamii, A.; Yosoi, M.; Heger, A.

    2007-02-23

    The Gamow-Teller strength distributions below the particle threshold in {sup 138}La and {sup 180}Ta, deduced from high-resolution measurements of the ({sup 3}He,t) reaction at 0 deg., allow us to evaluate the role of charged-current reactions for the production of these extremely rare nuclides in neutrino-nucleosynthesis models. The analysis suggests that essentially all {sup 138}La in the Universe can be made that way. Neutrino nucleosynthesis also contributes significantly to the abundance of {sup 180}Ta but the magnitude depends on the unknown branching ratio for population of the long-lived isomer.

  12. Ground and excited states Gamow-Teller strength distributions of iron isotopes and associated capture rates for core-collapse simulations

    NASA Astrophysics Data System (ADS)

    Nabi, Jameel-Un

    2011-02-01

    This paper reports on the microscopic calculation of ground and excited states Gamow-Teller (GT) strength distributions, both in the electron capture and electron decay direction, for 54,55,56Fe. The associated electron and positron capture rates for these isotopes of iron are also calculated in stellar matter. These calculations were recently introduced and this paper is a follow-up which discusses in detail the GT strength distributions and stellar capture rates of key iron isotopes. The calculations are performed within the framework of the proton-neutron quasiparticle random phase approximation (pn-QRPA) theory. The pn-QRPA theory allows a microscopic state-by-state calculation of GT strength functions and stellar capture rates which greatly increases the reliability of the results. For the first time experimental deformation of nuclei are taken into account. In the core of massive stars isotopes of iron, 54,55,56Fe, are considered to be key players in decreasing the electron-to-baryon ratio ( Y e ) mainly via electron capture on these nuclide. The structure of the presupernova star is altered both by the changes in Y e and the entropy of the core material. Results are encouraging and are compared against measurements (where possible) and other calculations. The calculated electron capture rates are in overall good agreement with the shell model results. During the presupernova evolution of massive stars, from oxygen shell burning stages till around end of convective core silicon burning, the calculated electron capture rates on 54Fe are around three times bigger than the corresponding shell model rates. The calculated positron capture rates, however, are suppressed by two to five orders of magnitude.

  13. Configuration splitting of the Gamow-Teller resonance in antimony isotopes: Is this a real or a virtual effect?

    SciTech Connect

    Igashov, S. Yu.; Rodin, V. A.; Urin, M. H.

    2013-04-15

    The Gamow-Teller strength functions for a number of antimony isotopes were calculated within a semimicroscopic approach based on the continuum version of the charge-exchange quasiparticle random-phase approximation and on phenomenologically taking into account the fragmentation effect. The structural effect of splitting of the main maximum of the Gamow-Teller resonance in these isotopes was confirmed. Experimental data on the excitation of this resonance in a direct and a resonance reaction for the {sup 118}Sn parent nucleus were analyzed with allowance for this effect.

  14. Gamow-Teller strengths in A=34 isobars: Comparison of the mirror transitions T{sub z}=+1{yields}0 and T{sub z}=-1{yields}0

    SciTech Connect

    Fujita, Y.; Neveling, R.; Smit, F. D.; Fujita, H.; Adachi, T.; Hatanaka, K.; Kaneda, T.; Matsubara, H.; Nakanishi, K.; Sakemi, Y.; Shimizu, Y.; Tamii, A.; Yosoi, M.; Botha, N. T.

    2007-05-15

    With a high energy-resolution of {delta}E=21 keV in the {sup 34}S({sup 3}He,t){sup 34}Cl measurement at 0 degree sign and at 140 MeV/nucleon, strengths of Fermi and Gamow-Teller (GT) transitions between T{sub z}=+1 and T{sub z}=0 states were studied, where T{sub z} is the z component of isospin T. The corresponding isospin-symmetric transitions connecting T{sub z}=-1 and T{sub z}=0 states can be studied in the {sup 34}Ar {beta}{sup +} decay. The strengths of corresponding GT transitions were compared up to the excitation energy (E{sub x}) of 3.1 MeV. A good agreement was observed for the two strong transitions to states around E{sub x}=3 MeV, while a disagreement of 40% was observed for a weaker transition to a low-lying state.

  15. Specificity of /sup 71/Ga(p,n)/sup 71/Ge at 35 MeV for Gamow-Teller strength

    SciTech Connect

    Baltz, A.J.; Weneser, J.; Brown, B.A.; Rapaport, J.

    1985-01-01

    The motivation for considering the /sup 71/Ga(p,n)/sup 71/Ge reaction is to help determine the properties of /sup 71/Ga as a detector of solar neutrinos. The proposed solar neutrino experiment, /sup 71/Ga(nu,e/sup -/)/sup 71/Ge, has a threshold of only .236 MeV, and is thus sensitive to neutrinos produced in the basic burning process in the sun p + p ..-->.. /sup 2/H + e/sup +/ + nu, which has a .420 MeV endpoint. The excitation of the (5/2)/sup -/ state at .175 MeV in /sup 71/Ge could be important, however. Were the Gamow-Teller (G-T) transition to the 175 keV state equal in strength to the ground state transition there would be approx. 25% added to the detector signal, the greater part of this coming from the /sup 7/Be neutrinos; the desired sensitivity to the p-p neutrinos would then be less.

  16. Comparative study of Gamow-Teller strength distributions in the odd-odd nucleus {sup 50}V and its impact on electron capture rates in astrophysical environments

    SciTech Connect

    Nabi, Jameel-Un; Sajjad, Muhammad

    2007-11-15

    Gamow-Teller (GT) strength transitions are an ideal probe for testing nuclear structure models. In addition to nuclear structure, GT transitions in nuclei directly affect the early phases of Type Ia and Type-II supernovae core collapse since the electron capture rates are partly determined by these GT transitions. In astrophysics, GT transitions provide an important input for model calculations and element formation during the explosive phase of a massive star at the end of its life-time. Recent nucleosynthesis calculations show that odd-odd and odd-A nuclei cause the largest contribution in the rate of change of lepton-to-baryon ratio. In the present manuscript, we have calculated the GT strength distributions and electron capture rates for odd-odd nucleus {sup 50}V by using the pn-QRPA theory. At present {sup 50}V is the first experimentally available odd-odd nucleus in fp-shell nuclei. We also compare our GT strength distribution with the recently measured results of a {sup 50}V(d, {sup 2}He){sup 50}Ti experiment, with the earlier work of Fuller, Fowler, and Newman (referred to as FFN) and subsequently with the large-scale shell model calculations. One curious finding of the paper is that the Brink's hypothesis, usually employed in large-scale shell model calculations, is not a good approximation to use at least in the case of {sup 50}V. SNe Ia model calculations performed using FFN rates result in overproduction of {sup 50}Ti, and were brought to a much acceptable value by employing shell model results. It might be interesting to study how the composition of the ejecta using presently reported QRPA rates compare with the observed abundances.

  17. Comparative study of Gamow-Teller strength distributions in the odd-odd nucleus V50 and its impact on electron capture rates in astrophysical environments

    NASA Astrophysics Data System (ADS)

    Nabi, Jameel-Un; Sajjad, Muhammad

    2007-11-01

    Gamow-Teller (GT) strength transitions are an ideal probe for testing nuclear structure models. In addition to nuclear structure, GT transitions in nuclei directly affect the early phases of Type Ia and Type-II supernovae core collapse since the electron capture rates are partly determined by these GT transitions. In astrophysics, GT transitions provide an important input for model calculations and element formation during the explosive phase of a massive star at the end of its life-time. Recent nucleosynthesis calculations show that odd-odd and odd-A nuclei cause the largest contribution in the rate of change of lepton-to-baryon ratio. In the present manuscript, we have calculated the GT strength distributions and electron capture rates for odd-odd nucleus V50 by using the pn-QRPA theory. At present V50 is the first experimentally available odd-odd nucleus in fp-shell nuclei. We also compare our GT strength distribution with the recently measured results of a V50(d, He2)Ti50 experiment, with the earlier work of Fuller, Fowler, and Newman (referred to as FFN) and subsequently with the large-scale shell model calculations. One curious finding of the paper is that the Brink's hypothesis, usually employed in large-scale shell model calculations, is not a good approximation to use at least in the case of V50. SNe Ia model calculations performed using FFN rates result in overproduction of Ti50, and were brought to a much acceptable value by employing shell model results. It might be interesting to study how the composition of the ejecta using presently reported QRPA rates compare with the observed abundances.

  18. Ratio of Gamow-Teller to Fermi strength observed in /sup 13,14/C(p,n) at 492 and 590 MeV

    SciTech Connect

    Ullmann, J.L.; Rapaport, J.; Lisowski, P.W.; Byrd, R.C.; Carey, T.; Taddeucci, T.N.; McClelland, J.; Rybarcyk, L.; Haight, R.C.; King, N.S.P.

    1988-01-01

    It has been recognized for a number of years that certain spin-isospin components of the nucleon-nucleus effective interaction can be inferred from (p,n) reactions to states of known nuclear structure. For L = 0, S = 0 and L = 0, S = 1 transitions, the 0-degree (p,n) cross section can be related respectively to Fermi and Gamow-Teller beta decay matrix elements. If these transitions occur in the same nucleus, the ratio of isovector spin-flip to non-spin-flip effective interactions can be measured without regard for absolute normalization. The best reaction to measure this is /sup 14/C(p,n) which goes by a pure Gamow-Teller transition to the 1/sup /plus// state at 3.95 MeV in /sup 14/N, and Fermi transition to the 2.31 MeV 0/sup /plus// state. This work extends the ratio measurements made at lower energies (ref. 1, 2, 3) to 492 and 590 MeV. We also report on the /sup 13/C(p,n) reaction which goes by a pure GT transition to the 3.51 MeV 3/2/sup /minus// state in /sup 13/N, but by a mixed Fermi plus Gamow-Teller transition to the 1/2/sup /minus// ground state. 11 refs., 4 figs., 2 tabs.

  19. Gamow-Teller Strength Distributions in {sup 48}Sc by the {sup 48}Ca(p,n) and {sup 48}Ti(n,p) Reactions and Two-Neutrino Double-beta Decay Nuclear Matrix Elements

    SciTech Connect

    Yako, K.; Sasano, M.; Miki, K.; Sakai, H.; Noji, S.; Dozono, M.; Ihara, E.; Wakasa, T.; Frekers, D.; Greenfield, M. B.; Hatanaka, K.; Kato, M.; Matsubara, H.; Okamura, H.; Sakemi, Y.; Tamii, A.; Kawabata, T.; Sakaguchi, S.; Sasamoto, Y.; Shimizu, Y.

    2009-07-03

    The double-differential cross sections for the {sup 48}Ca(p,n) and {sup 48}Ti(n,p) reactions were measured at 300 MeV. A multipole decomposition technique was applied to the spectra to extract the Gamow-Teller (GT) components. The integrated GT strengths up to an excitation energy of 30 MeV in {sup 48}Sc are 15.3+-2.2 and 2.8+-0.3 in the (p,n) and (n,p) spectra, respectively. In the (n,p) spectra additional GT strengths were found above 8 MeV where shell models within the fp shell-model space predict almost no GT strengths, suggesting that the present shell-model description of the nuclear matrix element of the two-neutrino double-beta decay is incomplete.

  20. Gamow-Teller 1{sup +} states in {sup 208}Bi

    SciTech Connect

    Babacan, T.; Salamov, D. I.; Kuecuekbursa, A.

    2005-03-01

    The properties of the Gamow-Teller (GT) 1{sup +} states in {sup 208}Bi have been investigated by using the Pyatov-Salamov method. The GT resonance (GTR) energy, the contribution of the GTR {beta} transition strength to the Ikeda sum rule, and the differential cross sections for the {sup 208}Pb(p,n){sup 208}Bi and {sup 208}Pb({sup 3}He,t){sup 208}Bi charge exchange reactions at different energies have been calculated. Our results show good agreement with experimental values.

  1. Nuclear shape dependence of Gamow-Teller distributions in neutron-deficient Pb isotopes

    SciTech Connect

    Sarriguren, P.; Moreno, O.; Alvarez-Rodriguez, R.; Moya de Guerra, E.

    2005-11-01

    We study Gamow-Teller strength distributions in the neutron-deficient even isotopes {sup 184-194}Pb in a search for signatures of deformation. The microscopic formalism used is based on a deformed quasiparticle random-phase approximation (QRPA) approach, which involves a self-consistent quasiparticle deformed Skyrme Hartree-Fock (HF) basis and residual spin-isospin forces in both the particle-hole and particle-particle channels. By analyzing the sensitivity of the Gamow-Teller strength distributions to the various ingredients in the formalism, we conclude that the {beta} decay of these isotopes could be a useful tool to look for fingerprints of nuclear deformation.

  2. Measurements of the {sup 116}Cd(p,n) and {sup 116}Sn(n,p) reactions at 300 MeV for studying Gamow-Teller transition strengths in the intermediate nucleus of the {sup 116}Cd double-{beta} decay

    SciTech Connect

    Sasano, M.; Kuboki, H.; Sekiguchi, K.; Sakai, H.; Yako, K.; Miki, K.; Noji, S.; Wakasa, T.; Dozono, M.; Fujita, K.; Greenfield, M. B.; Hatanaka, K.; Okamura, H.; Tamii, A.; Kawabata, T.; Maeda, Y.; Sakemi, Y.; Shimizu, Y.; Uesaka, T.; Sasamoto, Y.

    2009-11-09

    The double differential cross sections for the {sup 116}Cd(p,n) and {sup 116}Sn(n,p) reactions at 300 MeV have been measured over a wide excitation-energy region including Gamow-Teller (GT) giant resonance (GTGR) for studying GT transition strengths in the intermediate nucleus of the {sup 116}Cd double-{beta} decay, namely {sup 116}In. A large amount of the strengths in the {beta}{sup +} direction has been newly found in the energy region up to 30 MeV, which may imply that the GT strengths in the GTGR region contribute to the nuclear matrix element of the two-neutrino double-{beta} decay.

  3. Gamow-Teller Transitions Starting from Tz = +3/2 Nucleus 45Sc

    NASA Astrophysics Data System (ADS)

    Susoy, G.; Fujita, H.; Fujita, Y.; Adachi, T.; Algora, A.; Csatlos, M.; Deaven, J.; Estevez, E.; Ganioǧlu, E.; Guess, C.; Gulyás, J.; Hatanaka, K.; Hirota, K.; Ishikawa, D.; Krasznahorkay, A.; Matsubara, H.; Meharchand, R.; Molina, F.; Okamura, H.; Oktem, Y.; Ong, H. J.; Perdikakis, G.; Rubio, B.; Scholl, C.; Suzuki, T.; Tamii, A.; Thies, J.; Zegers, R. G. T.; Zenihiro, J.

    2011-10-01

    Owing to its simplicity and also its nature of spin-isospin (στ) excitation, Gamow-Teller (GT) transitions play key roles in the studies of nuclear structure as well as astro-nuclear processes. We studied GT transitions starting from 45Sc in a high-resolution (3He,t) charge-exchange reactions at 0° and at an intermediate incoming energy of 140 MeV/nucleon. Individual GT transitions were observed up to high excitation energy of 10 MeV and a concentration of GT strength, a resonance-like structure, was observed at 6.5 MeV.

  4. Magnetic Dipole and Gamow-Teller Modes in Neutrino-Nucleus Reactions: Impact on Supernova Dynamics and Nucleosynthesis

    SciTech Connect

    Neumann-Cosel, P. von; Byelikov, A.; Richter, A.; Shevchenko, A.; Adachi, T.; Fujita, Y.; Shimbara, Y.; Fujita, H.; Heger, A.; Kolbe, E.; Langanke, K.; Martinez-Pinedo, G.

    2006-03-13

    Some aspects of the importance of neutrino-induced reactions on nuclei within supernova physics are discussed. It is argued that important constraints on the experimentally unknown cross sections can be obtained from experimental studies of the nuclear response in selected cases. Examples are neutral-current induced reactions on fp-shell nuclei extracted from high-resolution inelastic electron scattering data providing the M1 strength distributions and the production of the exotic heavy, odd-odd nuclei 138La and 180Ta through charged-current reactions dominated by Gamow-Teller transitions. The Gamow-Teller strength can deduced from the (3He,t) charge-exchange reaction at zero degree.

  5. Gamow-Teller Transitions Starting from Tz = +3/2 Nucleus 47Ti

    NASA Astrophysics Data System (ADS)

    Ganioǧlu, E.; Fujita, H.; Fujita, Y.; Adachi, T.; Algora, A.; Csatlos, M.; Deaven, J.; Estevez, E.; Guess, C.; Gulyás, J.; Hatanaka, K.; Hirota, K.; Ishikawa, D.; Krasznahorkay, A.; Matsubara, H.; Meharchand, R.; Molina, F.; Okamura, H.; Ong, H. J.; Perdikakis, G.; Rubio, B.; Scholl, C.; Susoy, G.; Suzuki, T.; Tamii, A.; Thies, J.; Zegers, R. G. T.; Zenihiro, J.

    2011-10-01

    Gamow-Teller (GT) transitions are mediated by the στ operator. Owing to its simplicity and also its spin-isospin nature, GT transitions play key roles in the studies of nuclear structure as well as astro-nuclear processes. In violent neutrino-induced reactions at the core-collapse stage of type II supernovae, Gamow-Teller (GT) transitions starting from stable as well as unstable pf-shell nuclei play important roles. We study GT transitions starting from 47Ti in a high-resolution (3He,t) charge-exchange reactions at 0° and at an intermediate incident energy of 140 MeV/nucleon at Research Center for Nuclear Physics (RCNP), Osaka. Individual GT transitions up to high excitations were observed. Assuming the isospin symmetry for the strengths of Tz = ±3/2→±1/2 analogous GT transitions, we can deduce the detailed strength distribution starting from mirror unstable nucleus 47Mn.

  6. Gamow-Teller {beta}{sup +} decay of deformed nuclei near the proton drip line

    SciTech Connect

    Frisk, F.; Hamamoto, I.; Zhang, X.Z. |

    1995-11-01

    Using a quasiparticle Tamm-Dancoff approximation (TDA) based on deformed Hartree-Fock (HF) calculations with Skyrme interactions, the distribution of the Gamow-Teller (GT) {beta}{sup +} decay strength is estimated for the HF local minima of even-even deformed nuclei near the proton drip line in the region of 28{lt}{ital Z}{lt}66. The distribution often depends sensitively on the nuclear shape (namely, oblate or prolate). In the region of {ital Z}{lt}50 the possibility of observing {beta}-delayed proton emission depends sensitively on the excess of {ital Z} over {ital Z}={ital N}. In the region of {ital Z}{gt}50 almost the entire estimated GT strength is found to lie below the ground states of the even-even mother nuclei, and the observation of the total GT strength by {beta}-delayed charged-particle(s) emission will be of essential importance.

  7. Deformation signature from the Gamow-Teller decay of N=Z nuclei

    SciTech Connect

    Miehe, Ch.; Dessagne, Ph.; Huck, A.; Knipper, A.; Marguier, G.; Longour, C.; Rauch, V.; Giovinazzo, J.; Borge, M. J. G.; Piqueras, I.; Tengblad, O.; Jokinen, A.; Ramdhane, M.

    1998-12-21

    The {sup 76}Sr (N=Z=38) and the {sup 72}Kr (N=Z=36) {beta}{sup +} EC decay have been studied at the CERN/ISOLDE PSB facility where their beta-gamma and delayed particle decay modes have been investigated. The established decay schemes yield new information on the Gamow-Teller (GT) strength spread over the J{sup {pi}}=1{sup +} states in the daughter nuclei. The delayed proton emission of an N=Z nucleus is observed for the first time in the case of {sup 76}Sr. The experimental GT strength intensities and distributions are discussed in the light of the theoretical estimates for oblate and prolate deformations.

  8. Gamow-Teller unit cross sections for (t,{sup 3}He) and ({sup 3}He,t) reactions

    SciTech Connect

    Perdikakis, G.; Austin, Sam M.; Galaviz, D.; Tur, C.; Zegers, R. G. T.; Deaven, J. M.; Guess, C. J.; Hitt, G. W.; Meharchand, R.; Bazin, D.; Grinyer, G. F.; Caesar, C.; Herlitzius, C.; Gade, A.; Howard, M. E.; Smith, E. E.; Noji, S.; Sakai, H.; Shimbara, Y.

    2011-05-15

    The proportionality between differential cross sections at vanishing linear momentum transfer and Gamow-Teller transition strength, expressed in terms of the unit cross section ({sigma}{sub GT}), was studied as a function of target mass number for (t,{sup 3}He) and ({sup 3}He,t) reactions at 115A MeV and 140A MeV, respectively. Existing ({sup 3}He,t) and (t,{sup 3}He) data on targets with mass number 12{<=}A{<=}120 were complemented with new and reevaluated (t,{sup 3}He) data on proton, deuteron, {sup 6}Li, and {sup 12}C targets. It was found that in spite of the small difference in beam energies between the two probes, the unit cross sections have a nearly identical and simple dependence on target mass number A, for A{>=}12: {sigma}{sub GT}=109/A{sup 0.65}. The factorization of the unit cross sections in terms of a kinematical factor, a distortion factor, and the strength of the effective spin-isospin transfer nucleus-nucleus interaction was investigated. Simple phenomenological functions depending on mass number A were extracted for the latter two. By comparison with plane and distorted-wave Born approximation calculations, it was found that the use of a short-range approximation for knock-on exchange contributions to the transition amplitude results in overestimated cross sections for reactions involving the composite ({sup 3}He,t) and (t,{sup 3}He) probes.

  9. Gamow-Teller Transitions in Stable and Unstable pf-shell Nuclei

    SciTech Connect

    Fujita, Y.; Rubio, B.; Gelletly, W.

    2008-11-11

    Gamow-Teller (GT) transitions starting from stable as well as unstable pf-shell nuclei are of interest not only in nuclear physics, but also in astrophysics, e.g. in violent neutrino-induced reactions at the core-collapse stage of type II supernovae. In the {beta}-decay study of these pf-shell nuclei, half-lives can be measured rather accurately. On the other hand, in high-resolution ({sup 3}He,t) charge-exchange reactions at 0 deg., individual GT transitions up to high excitations can be studied. Assuming the isospin symmetry for the strengths of T{sub z} = {+-}1{yields}0 analogous GT transitions, we present a unique 'merged analysis' for the determination of absolute B(GT) values. This method can be applied not only to T = 1 systems, but also to higher T systems.

  10. Reexamining Gamow-Teller decays near 78Ni

    NASA Astrophysics Data System (ADS)

    Alshudifat, M. F.; Grzywacz, R.; Madurga, M.; Gross, C. J.; Rykaczewski, K. P.; Batchelder, J. C.; Bingham, C.; Borzov, I. N.; Brewer, N. T.; Cartegni, L.; Fijałkowska, A.; Hamilton, J. H.; Hwang, J. K.; Ilyushkin, S. V.; Jost, C.; Karny, M.; Korgul, A.; Królas, W.; Liu, S. H.; Mazzocchi, C.; Mendez, A. J.; Miernik, K.; Miller, D.; Padgett, S. W.; Paulauskas, S. V.; Ramayya, A. V.; Stracener, D. W.; Surman, R.; Winger, J. A.; Wolińska-Cichocka, M.; Zganjar, E. F.

    2016-04-01

    Decays of neutron-rich nuclei Zn,8382 and Ga,8382 produced in proton-induced fission of 238U were studied at the Holifield Radioactive Ion Beam Facility using on-line mass separation and β -γ spectroscopy techniques. New γ -ray transitions were identified and level schemes, which include states at high excitation energies in the range between 3-7 MeV were constructed. These high-energy levels were identified to be populated through allowed Gamow-Teller β transitions, and their structure was interpreted with new shell-model calculations. A β -delayed neutron branching ratio of 69 ±7 % was deduced for 82Zn and revised β -decay half-life values of 82Zn [155(17)(20) ms] and 83Zn [122(28) ms] were determined.

  11. Gamow-Teller Transitions Starting from T{sub z} = +3/2 Nucleus {sup 45}Sc

    SciTech Connect

    Susoy, G.; Ganioglu, E.; Oktem, Y.; Fujita, H.; Fujita, Y.; Adachi, T.; Hatanaka, K.; Hirota, K.; Ishikawa, D.; Matsubara, H.; Okamura, H.; Ong, H. J.; Suzuki, T.; Tamii, A.; Zenihiro, J.; Algora, A.; Estevez, E.; Molina, F.; Rubio, B.; Csatlos, M.

    2011-10-28

    Owing to its simplicity and also its nature of spin-isospin ({sigma}{tau}) excitation, Gamow-Teller (GT) transitions play key roles in the studies of nuclear structure as well as astro-nuclear processes. We studied GT transitions starting from {sup 45}Sc in a high-resolution ({sup 3}He,t) charge-exchange reactions at 0 deg. and at an intermediate incoming energy of 140 MeV/nucleon. Individual GT transitions were observed up to high excitation energy of 10 MeV and a concentration of GT strength, a resonance-like structure, was observed at 6.5 MeV.

  12. Gamow-Teller transitions to {sup 64}Cu measured with the {sup 64}Zn(t,{sup 3}He) reaction

    SciTech Connect

    Hitt, G. W.; Zegers, R. G. T.; Guess, C. J.; Austin, Sam M.; Galaviz, D.; Shimbara, Y.; Tur, C.; Bazin, D.; Gade, A.; Horoi, M.; Howard, M. E.; Smith, E. E.; Rae, W. D. M.

    2009-07-15

    The {sup 64}Zn(t,{sup 3}He) reaction has been studied by using a secondary triton beam of 115 MeV/nucleon to extract the Gamow-Teller transition-strength distribution to {sup 64}Cu. The results were compared with shell-model calculations with the pf-shell effective interactions KB3G and GXPF1A and with existing data from the {sup 64}Zn(d,{sup 2}He) reaction. Whereas the experimental results exhibited good consistency, neither of the theoretical predictions managed to reproduce the data. The implications for electron-capture rates during late stellar evolution were investigated. The rates based on the theoretical strength distributions are lower by factors of 3.5-5 compared to the rates based on experimental strength distributions.

  13. Observations of the Gamow-Teller resonance in the rare-earth nuclei above 146Gd populated in β decay

    NASA Astrophysics Data System (ADS)

    Nácher, E.; Rubio, B.; Algora, A.; Cano-Ott, D.; Taín, J. L.; Gadea, A.; Agramunt, J.; Gierlik, M.; Karny, M.; Janas, Z.; Roeckl, E.; Blazhev, A.; Collatz, R.; Döring, J.; Hellström, M.; Hu, Z.; Kirchner, R.; Mukha, I.; Plettner, C.; Shibata, M.; Rykaczewski, K.; Batist, L.; Moroz, F.; Wittmann, V.; Valiente-Dobón, J. J.

    2016-01-01

    The rare-earth region of the nuclear table around the quasi-doubly magic nucleus 146Gd is one of the very few places in which the Gamow-Teller (GT) resonance can be populated in β decay. The appropriate technique to study such a phenomenon is total absorption spectroscopy, thanks to which one can measure the B (GT) distribution in β -decay experiments even when it is very fragmented and lies at high excitation energy in the daughter nucleus. Results on the GT resonance measured in the β decay of the odd-Z , N =83 nuclei 148Tb 150Ho, and 152Tm are presented in this work and compared with shell-model calculations. The tail of the resonance is clearly observed up to the limit imposed by the Q value. This observation is important in the context of the understanding of the "quenching" of the GT strength.

  14. Semimicroscopic description of basic modes of relaxation of the Gamow-Teller resonance

    SciTech Connect

    Safonov, I. V. Urin, M. H.

    2012-12-15

    Semimicroscopic approach based on the continuum version of the random-phase approximation and on a phenomenological method for taking into account the fragmentation effect is used to describe quantitatively basic relaxation parameters of the Gamow-Teller resonance in magic and nearmagic nuclei. For the {sup 208}Bi nucleus, the results obtained by calculating the resonance parameters in question are compared with respective experimental data.

  15. Gamow-Teller transitions to 45Ca via the 45Sc(t ,3He+γ ) reaction at 115 MeV/u and its application to stellar electron-capture rates

    NASA Astrophysics Data System (ADS)

    Noji, S.; Zegers, R. G. T.; Austin, Sam M.; Baugher, T.; Bazin, D.; Brown, B. A.; Campbell, C. M.; Cole, A. L.; Doster, H. J.; Gade, A.; Guess, C. J.; Gupta, S.; Hitt, G. W.; Langer, C.; Lipschutz, S.; Lunderberg, E.; Meharchand, R.; Meisel, Z.; Perdikakis, G.; Pereira, J.; Recchia, F.; Schatz, H.; Scott, M.; Stroberg, S. R.; Sullivan, C.; Valdez, L.; Walz, C.; Weisshaar, D.; Williams, S. J.; Wimmer, K.

    2015-08-01

    Background: Stellar electron-capture reactions on medium-heavy nuclei are important for many astrophysical phenomena, including core-collapse and thermonuclear supernovæ and neutron stars. Estimates of electron-capture rates rely on accurate estimates of Gamow-Teller strength distributions, which can be extracted from charge-exchange reactions at intermediate beam energies. Measured Gamow-Teller transition strength distributions for stable pf-shell nuclei are reasonably well reproduced by theoretical calculations in the shell model, except for lower mass nuclei where admixtures from the sd shell can become important. Purpose: This paper presents a β+ charge-exchange experiment on 45Sc , one of the lightest pf-shell nuclei. The focus was on Gamow-Teller transitions to final states at low excitation energies, which are particularly important for accurate estimations of electron-capture rates at relatively low stellar densities. The experimental results are compared with various theoretical models. Method: The double-differential cross section for the 45Sc(t ,3He+γ ) reaction was measured using the NSCL Coupled-Cyclotron Facility at 115 MeV /u . Gamow-Teller contributions to the excitation-energy spectra were extracted by means of a multipole-decomposition analysis. γ rays emitted due to the deexcitation of 45Ca were measured using GRETINA to allow for the extraction of Gamow-Teller strengths from very weak transitions at low excitation energies. Results: Gamow-Teller transition strengths to 45Ca were extracted up to an excitation energy of 20 MeV, and that to the first excited state in 45Ca at 174 keV was extracted from the γ -ray measurement, which, even though weak, is important for the astrophysical applications and dominates under certain stellar conditions. Shell-model calculations performed in the pf shell-model space with the GXPF1A, KB3G, and FPD6 interactions did not reproduce the experimental Gamow-Teller strength distribution, and a calculation using

  16. Gamow-Teller transitions studied in the high-resolution Ni64(He3,t)Cu64 reaction

    NASA Astrophysics Data System (ADS)

    Popescu, L.; Adachi, T.; Berg, G. P. A.; Brentano, P. Von; Frekers, D.; Frenne, D. De; Fujita, K.; Fujita, Y.; Grewe, E.-W.; Harakeh, M. N.; Hatanaka, K.; Jacobs, E.; Nakanishi, K.; Negret, A.; Sakemi, Y.; Shimbara, Y.; Shimizu, Y.; Tameshige, Y.; Tamii, A.; Uchida, M.; Wörtche, H. J.; Yosoi, M.

    2009-06-01

    To study the Gamow-Teller (GT) transitions to the pf-shell nucleus Cu64, the Ni64(He3,t)Cu64 experiment was performed at the Research Center for Nuclear Physics (RCNP) Ring Cyclotron, Osaka, using a He3 beam of 140 MeV/nucleon. The outgoing tritons were momentum analyzed by the Grand Raiden spectrometer at 0°. A high energy resolution of 32 keV (full width at half-maximum) allowed the separation of individual levels in the excitation-energy region from 0 to 3.5 MeV. In addition to the ground state (gs), known to be a Jπ=1+ GT state, many low-lying states showed L=0 nature, suggesting that they are candidates for GT states. Because the GT strength B(GT) for the gs transition is known from the β-decay measurement, the strengths for the excited states could be determined using the proportionality between the B(GT) and the reaction cross section extrapolated to q=0 momentum transfer. At higher excitation energies, the level density becomes high and the so-called GT giant resonance dominates the spectrum. The lower and the upper limits of the strength contained in this energy region were estimated. Our results show that less than 55% of the strength predicted by the Ikeda sum rule is located in the excitation-energy region from 0 to 17 MeV.

  17. Evidence for Gamow-Teller Decay of ^{78}Ni Core from Beta-Delayed Neutron Emission Studies.

    PubMed

    Madurga, M; Paulauskas, S V; Grzywacz, R; Miller, D; Bardayan, D W; Batchelder, J C; Brewer, N T; Cizewski, J A; Fijałkowska, A; Gross, C J; Howard, M E; Ilyushkin, S V; Manning, B; Matoš, M; Mendez, A J; Miernik, K; Padgett, S W; Peters, W A; Rasco, B C; Ratkiewicz, A; Rykaczewski, K P; Stracener, D W; Wang, E H; Wolińska-Cichocka, M; Zganjar, E F

    2016-08-26

    The β-delayed neutron emission of ^{83,84}Ga isotopes was studied using the neutron time-of-flight technique. The measured neutron energy spectra showed emission from states at excitation energies high above the neutron separation energy and previously not observed in the β decay of midmass nuclei. The large decay strength deduced from the observed intense neutron emission is a signature of Gamow-Teller transformation. This observation was interpreted as evidence for allowed β decay to ^{78}Ni core-excited states in ^{83,84}Ge favored by shell effects. We developed shell model calculations in the proton fpg_{9/2} and neutron extended fpg_{9/2}+d_{5/2} valence space using realistic interactions that were used to understand measured β-decay lifetimes. We conclude that enhanced, concentrated β-decay strength for neutron-unbound states may be common for very neutron-rich nuclei. This leads to intense β-delayed high-energy neutron and strong multineutron emission probabilities that in turn affect astrophysical nucleosynthesis models. PMID:27610848

  18. Evidence for Gamow-Teller Decay of 78Ni Core from Beta-Delayed Neutron Emission Studies

    NASA Astrophysics Data System (ADS)

    Madurga, M.; Paulauskas, S. V.; Grzywacz, R.; Miller, D.; Bardayan, D. W.; Batchelder, J. C.; Brewer, N. T.; Cizewski, J. A.; Fijałkowska, A.; Gross, C. J.; Howard, M. E.; Ilyushkin, S. V.; Manning, B.; Matoš, M.; Mendez, A. J.; Miernik, K.; Padgett, S. W.; Peters, W. A.; Rasco, B. C.; Ratkiewicz, A.; Rykaczewski, K. P.; Stracener, D. W.; Wang, E. H.; Wolińska-Cichocka, M.; Zganjar, E. F.

    2016-08-01

    The β -delayed neutron emission of Ga,8483 isotopes was studied using the neutron time-of-flight technique. The measured neutron energy spectra showed emission from states at excitation energies high above the neutron separation energy and previously not observed in the β decay of midmass nuclei. The large decay strength deduced from the observed intense neutron emission is a signature of Gamow-Teller transformation. This observation was interpreted as evidence for allowed β decay to 78Ni core-excited states in Ge,8483 favored by shell effects. We developed shell model calculations in the proton f p g9 /2 and neutron extended f p g9 /2+d5 /2 valence space using realistic interactions that were used to understand measured β -decay lifetimes. We conclude that enhanced, concentrated β -decay strength for neutron-unbound states may be common for very neutron-rich nuclei. This leads to intense β -delayed high-energy neutron and strong multineutron emission probabilities that in turn affect astrophysical nucleosynthesis models.

  19. Gamow-Teller and first-forbidden decays near the r-process paths at N=50, 82, and 126

    NASA Astrophysics Data System (ADS)

    Borzov, I. N.

    2003-02-01

    The β-decay rates of neutron-rich nuclei relevant to the r-process nucleosynthesis are mostly beyond experimental reach. Their predictions demand a self-consistent extrapolation of various nuclear properties away from the experimentally known regions. The allowed transitions approximation commonly used in large-scale microscopic calculations also needs to be revised in different mass regions. The density functional+continuum QRPA approximation to self-consistent calculations of the ground state properties, Gamow-Teller and first-forbidden β-decay transitions of nuclei far from stability is developed. Systematic calculations are performed of the allowed and first-forbidden β-decay rates for the r-process relevant nuclides near the closed neutron shells at N=50,82,126. The importance of first-forbidden decays near Z⩾50, N≈82 and near N=126 is shown. The total β-decay half-lives in the region “east” of the 208Pb are estimated. A comparison with recent experimental data, global calculations, and self-consistent microscopic predictions is presented.

  20. Projected shell model for Gamow-Teller transitions in heavy, deformed nuclei

    NASA Astrophysics Data System (ADS)

    Wang, Long-Jun; Sun, Yang; Gao, Zao-Chun; Kiran Ghorui, Surja

    2016-02-01

    Calculations of Gamow-Teller (GT) transition rates for heavy, deformed nuclei, which are useful input for nuclear astrophysics studies, are usually done with the quasiparticle random-phase approximation. We propose a shell-model method by applying the Projected Shell Model (PSM) based on deformed bases. With this method, it is possible to perform a state-by-state calculation for nuclear matrix elements for β-decay and electron-capture in heavy nuclei. Taking β- decay from 168Dy to 168Ho as an example, we show that the known experimental B(GT) from the ground state of the mother nucleus to the low-lying states of the daughter nucleus could be well described. Moreover, strong transitions to high-lying states are predicted to occur, which may considerably enhance the total decay rates once these nuclei are exposed to hot stellar environments.

  1. Study of Gamow-Teller transitions with J = 0 and Jmax pairing

    NASA Astrophysics Data System (ADS)

    Garcia, Ricardo; Zamick, Larry

    2015-10-01

    Allowed Gamow-Teller transitions are sensitive to the interactions which are used. In this single j shell study, we consider the 2 extremes J = 0 pairing and Jmax pairing as well as ``half.'' Also, for comparison, a realistic interaction, MBZE. For 43Sc decay J = 0 pairing yields a maximum B(GT) for I = 7/2 to 7/2 but is zero for 7/2 to 9/2 and 7/2 to 5/2. This is tied to a selection rule that one cannot simultaneously change reduced isospin and seniority. For 46Ti I = 1 to I = 0 there is not monotonic behavior as one goes from Jmax to J = 0 pairing, explained by the fact that that there is an isospin crossover of J = 1 T = 2 as one goes to the J=0 pairing limit. Comparison with experiment is made. RG has received support via the Research Undergraduate Experience program (REU) from the U.S. National Science Foundation through grant PHY-1263280, and thanks the REU Physics program at Rutgers University for their support.

  2. Direct proton decay from the Gamow-Teller resonance in {sup 208}Bi

    SciTech Connect

    Akimune, H.; Daito, I.; Fujita, Y.; Fujiwara, M.; Greenfield, M.B.; Harakeh, M.N.; Inomata, T.; Jaenecke, J.; Katori, K.; Nakayama, S.; Sakai, H.; Sakemi, Y.; Tanaka, M.; Yosoi, M. ||||||||

    1995-08-01

    Spin-isospin excitations in {sup 208}Bi have been investigated using the {sup 208}Pb ({sup 3}He,{ital t}){sup 208}Bi reaction at near {theta}{approx}0{degree} at {ital E}({sup 3}He)=450 MeV. The microscopic structure of the Gamow-Teller resonance (GTR), the isobaric analog state (IAS), and the spin-flip dipole ({Delta}{ital L}=1) resonance (SDR) in {sup 208}Bi has been studied by observing their direct proton decays to the low-lying neutron-hole states in {sup 207}Pb. Decay protons were measured at backward angles in coincidence with tritons detected at and near 0{degree}. The total branching ratio for proton decay from the GTR is determined to be only 4.9{plus_minus}1.3%. The total branching ratio for proton decay from the SDR amounts to 14.1{plus_minus}4.2%. The deduced total widths as well as the total and partial proton escape widths of the GRR and IAS are found to be in reasonable agreement with recent theoretical estimates obtained in the framework of the continuum Tamm-Dancoff approximation.

  3. High-resolution study of Gamow-Teller transitions from the Tz=1 nucleus 46Ti to the Tz=0 nucleus 46V

    NASA Astrophysics Data System (ADS)

    Adachi, T.; Fujita, Y.; Brentano, P. Von; Lisetskiy, A. F.; Berg, G. P.; Fransen, C.; Frenne, D. De; Fujita, H.; Fujita, K.; Hatanaka, K.; Honma, M.; Jacobs, E.; Kamiya, J.; Kawase, K.; Mizusaki, T.; Nakanishi, K.; Negret, A.; Otsuka, T.; Pietralla, N.; Popescu, L.; Sakemi, Y.; Shimbara, Y.; Shimizu, Y.; Tameshige, Y.; Tamii, A.; Uchida, M.; Wakasa, T.; Yosoi, M.; Zell, K. O.

    2006-02-01

    The Gamow-Teller (GT) transition strengths in fp-shell nuclei are important parameters in presupernova models. A high-energy-resolution (3He,t) experiment was performed on the Tz=1 nucleus 46Ti at 0° and at an intermediate incident energy of 140 MeV/nucleon for the study of precise GT transition strengths to the final Tz=0 nucleus 46V. With an energy resolution of 33 keV, individual GT transitions were observed and GT strengths were derived for them up to the excitation energy of 4.5 MeV. The GT strengths were compared with shell-model calculations using various effective interactions. In this low-lying region, most GT states have isospin T=0. A few GT states with isospin T=1 were identified from the existence of the corresponding (analog) M1 states in 46Ti. By comparing the GT strength with the corresponding (analogous) M1 transition strength studied in 46Ti(e,e') or (γ,γ') measurements, a large constructive interference of orbital and spin terms was suggested for one of these M1 transitions.

  4. Fine Structure of the Gamow-Teller Resonance in {sup 90}Nb and Level Density of 1{sup +} States

    SciTech Connect

    Kalmykov, Y.; Neumann-Cosel, P. von; Ponomarev, V.Yu.; Richter, A.; Shevchenko, A.; Wambach, J.; Adachi, T.; Fujita, Y.; Shimbara, Y.; Berg, G.P.A.; Fujita, K.; Hatanaka, K.; Kamiya, J.; Nakanishi, K.; Sakamoto, N.; Sakemi, Y.; Shimizu, Y.; Wakasa, T.; Fujita, H.; Smit, F.D.

    2006-01-13

    The fine structure of the Gamow-Teller resonance in a medium-heavy nucleus is observed for the first time in a high-resolution {sup 90}Zr({sup 3}He,t){sup 90}Nb experiment at the Research Center for Nuclear Physics, Osaka. Using a novel wavelet analysis technique, it is possible to extract characteristic energy scales and to quantify their relative importance for the generation of the fine structure. This method combined with the selectivity of the reaction permits an extraction of the level density of 1{sup +} states in {sup 90}Nb.

  5. Chiral two-body currents in nuclei: Gamow-Teller transitions and neutrinoless double-beta decay.

    PubMed

    Menéndez, J; Gazit, D; Schwenk, A

    2011-08-01

    We show that chiral effective field theory (EFT) two-body currents provide important contributions to the quenching of low-momentum-transfer Gamow-Teller transitions, and use chiral EFT to predict the momentum-transfer dependence that is probed in neutrinoless double-beta (0νββ) decay. We then calculate for the first time the 0νββ decay operator based on chiral EFT currents and study the nuclear matrix elements at successive orders. The contributions from chiral two-body currents are significant and should be included in all calculations. PMID:21902315

  6. Fermi to Gamow-Teller Mixing Ratios in the Nuclear Beta Decays of COBALT-58 and COBALT-56.

    NASA Astrophysics Data System (ADS)

    Lee, Wen-Piao

    1981-06-01

    The Fermi to Gamow-Teller mixing ratios, y = C(,V)M(,F)/C(,A)M(,GT), in the isospin-hindered beta decays ((DELTA)J=0, T=('(+OR -))1) of ('58)Co and ('56)Co have been accurately determined from extensive and detailed studies of the directional distributions of beta rays and gamma rays emitted from oriented ('58)Co and ('56)Co nuclei. The cobalt nuclei were oriented in a thin foil of permendur (49%Co, 49%Fe, and 2%V) magnetically saturated at ultralow temperatures (10('-2o)K). The nuclear orientation system employed has the distinguished features of excellent long-term temperature stability and of allowing beta rays be measured at almost any desired angle with respect to the nuclear orientation axis with very little deflections from their original trajectories by the applied magnetizing fields. Beta-ray and gamma-ray spectra were measured, with a Si(Li) detector and a Ge(Li) detector respectively, at four different angles with respect to the nuclear orientation axis. The gamma-ray background in the beta-ray spectra is removed by means of a mechanical shutter. The beta -ray asymmetries and the gamma-ray anisotropies were determined independently at each angle by normalizing the cold ((TURNEQ)10(' -2o)K) spectra by the corresponding warm (4.2(DEGREES)K) spectra taken at the same angle. Necessary corrections made on the beta-ray spectra due to the various experimental effects are described in detail. The experimental beta -ray asymmetries after the proper corrections were found to be in very good agreement with the theoretical expectations over a wide energy region. Including all estimated systematic errors, the beta-ray asymmetry parameters, A(,(beta)), were determined to be A(,(beta))('58) = 0.341 (+OR-) 0.020 for ('58)Co and A('56) = 0.352 (+OR-) 0.015 for ('56)Co. The Fermi to Gamov-Teller mixing ratios y corresponding to these A(,(beta))'s are y('58) = -0.005 (+OR-) 0.012 for ('58)Co and y('56) = -0.086 (+OR-) 0.008 for ('56)Co. The obtained result of y('56) is in

  7. Extraction of Weak Transition Strengths via the (He3, t) Reaction at 420MeV

    NASA Astrophysics Data System (ADS)

    Zegers, R. G. T.; Adachi, T.; Akimune, H.; Austin, Sam M.; van den Berg, A. M.; Brown, B. A.; Fujita, Y.; Fujiwara, M.; Galès, S.; Guess, C. J.; Harakeh, M. N.; Hashimoto, H.; Hatanaka, K.; Hayami, R.; Hitt, G. W.; Howard, M. E.; Itoh, M.; Kawabata, T.; Kawase, K.; Kinoshita, M.; Matsubara, M.; Nakanishi, K.; Nakayama, S.; Okumura, S.; Ohta, T.; Sakemi, Y.; Shimbara, Y.; Shimizu, Y.; Scholl, C.; Simenel, C.; Tameshige, Y.; Tamii, A.; Uchida, M.; Yamagata, T.; Yosoi, M.

    2007-11-01

    Differential cross sections for transitions of known weak strength were measured with the (He3, t) reaction at 420 MeV on targets of C12, C13, O18, Mg26, Ni58, Ni60, Zr90, Sn118, Sn120, and Pb208. Using these data, it is shown that the proportionalities between strengths and cross sections for this probe follow simple trends as a function of mass number. These trends can be used to confidently determine Gamow-Teller strength distributions in nuclei for which the proportionality cannot be calibrated via β-decay strengths. Although theoretical calculations in the distorted-wave Born approximation overestimate the data, they allow one to understand the main experimental features and to predict deviations from the simple trends observed in some of the transitions.

  8. Extraction of weak transition strengths via the (3He, t) reaction at 420 MeV.

    PubMed

    Zegers, R G T; Adachi, T; Akimune, H; Austin, Sam M; van den Berg, A M; Brown, B A; Fujita, Y; Fujiwara, M; Galès, S; Guess, C J; Harakeh, M N; Hashimoto, H; Hatanaka, K; Hayami, R; Hitt, G W; Howard, M E; Itoh, M; Kawabata, T; Kawase, K; Kinoshita, M; Matsubara, M; Nakanishi, K; Nakayama, S; Okumura, S; Ohta, T; Sakemi, Y; Shimbara, Y; Shimizu, Y; Scholl, C; Simenel, C; Tameshige, Y; Tamii, A; Uchida, M; Yamagata, T; Yosoi, M

    2007-11-16

    Differential cross sections for transitions of known weak strength were measured with the (3He, t) reaction at 420 MeV on targets of 12C, 13C, 18O, 26Mg, 58Ni, 60Ni, 90Zr, 118Sn, 120Sn, and 208Pb. Using these data, it is shown that the proportionalities between strengths and cross sections for this probe follow simple trends as a function of mass number. These trends can be used to confidently determine Gamow-Teller strength distributions in nuclei for which the proportionality cannot be calibrated via beta-decay strengths. Although theoretical calculations in the distorted-wave Born approximation overestimate the data, they allow one to understand the main experimental features and to predict deviations from the simple trends observed in some of the transitions.

  9. The N=83 nucleus149Dy from Gamow-Teller decay of its 11/2- and 1/2+ 149Ho parents

    NASA Astrophysics Data System (ADS)

    Menegazzo, R.; Kleinheinz, P.; Collatz, R.; Güven, H.; Styczen, J.; Schardt, D.; Keller, H.; Klepper, O.; Walter, G.; Huck, A.; Marguier, G.; Blomqvist, J.

    1994-03-01

    A high-sensitivity γ-spectroscopic study of the149Ho πh 11/2 and πs 1/2 β-decays using mass separated sources has located dominant 0+ → 1+ GT decay strength associated with decay of paired h 11/2 protons, leading to 3 п-states in the149Dy daughter nucleus. In their γ-decay low-lying149Dy levels characteristic of an N=83 nucleus are excited. They include the νf 7/2, νp 3/2, νh 9/2 and νp 1/2 single particle- and the νs {1/2/-1} and νd {3/2/-1} two-particle one-hole states, as well as the ν f 7/2 × 3- and νf 7/2 × 2+ particle-phonon multiplets. A synopsis is given of these excitations in the N=83 isotones from149Nd to153Yb. The149Dy GT decay strength is discussed in terms of the147Tb82 and148Dy82 decays. The strength function results are also compared with independent149Ho 11/2- decay data from the literature based on total γ-ray absorption measurements.

  10. Systematics of photon strength functions

    NASA Astrophysics Data System (ADS)

    Firestone, Richard

    2015-10-01

    The photon strength of high energy E1 transitions is well described by Brink-Axel theory based on the contribution of the Giant Dipole Resonance. No adequate theory is available for M1 and E2 transitions which do not generally compete strongly with high energy E1 transitions. Measurements with the 57Fe(3He,3He') reaction at the Oslo cyclotron have revealed that the photon strength below 2 MeV greatly exceeds BA predictions. Similar results have been found for numerous other nuclides. In this paper I will discuss my analysis of the 56Fe(n,γ)57Fe reaction which we investigated with both cold neutrons from the Budapest Reactor and thermal neutrons from the Rez Reactor (Prague). A >99% complete 57Fe capture γ-ray decay scheme containing 449 γ-rays deexciting 100 levels has been constructed on the basis of γ-ray singles and γγ -coincidence data. The photon strengths for 90 primary γ-rays with energies ranging from 92-7646 keV were calculated and compared with the predictions of Brink-Axel (BA) theory. Excellent agreement has been attained for the high energy transitions while the strength below 2 MeV exceeds BA predictions confirming the earlier Oslo (3He,3He' γ) results. Photon strengths for another 95 secondary M1, E1, and E2 γ-rays were also determined to also exceed BA predictions for transitions below 4 MeV. The dependence of photon strength on level energy and the statistical distribution of photon strengths will also be discussed in this talk.

  11. Correlated Strength in the Nuclear Spectral Function

    SciTech Connect

    D. Rohe; C. S. Armstrong; R. Asaturyan; O. K. Baker; S. Bueltmann; C. Carasco; D. Day; R. Ent; H. C. Fenker; K. Garrow; A. Gasparian; P. Gueye; M. Hauger; A. Honegger; J. Jourdan; C. E. Keppel; G. Kubon; R. Lindgren; A. Lung; D. J. Mack; J. H. Mitchell; H. Mkrtchyan; D. Mocelj; K. Normand; T. Petitjean; O. Rondon; E. Segbefia; I. Sick; S. Stepanyan; L. Tang; F. Tiefenbacher; W. F. Vulcan; G. Warren; S. A. Wood; L. Yuan; M. Zeier; H. Zhu; B. Zihlmann

    2004-10-01

    We have carried out an (e,ep) experiment at high momentum transfer and in parallel kinematics to measure the strength of the nuclear spectral function S(k,E) at high nucleon momenta k and large removal energies E. This strength is related to the presence of short-range and tensor correlations, and was known hitherto only indirectly and with considerable uncertainty from the lack of strength in the independent-particle region. This experiment locates by direct measurement the correlated strength predicted by theory.

  12. Monopole strength function of deformed superfluid nuclei

    NASA Astrophysics Data System (ADS)

    Stoitsov, M.; Kortelainen, M.; Nakatsukasa, T.; Losa, C.; Nazarewicz, W.

    2011-10-01

    We present an efficient method for calculating strength functions using the finite-amplitude method (FAM) for deformed superfluid heavy nuclei within the framework of the nuclear density functional theory. We demonstrate that FAM reproduces strength functions obtained with the fully self-consistent quasiparticle random-phase approximation (QRPA) at a fraction of the computational cost. As a demonstration, we compute the isoscalar and isovector monopole strengths for strongly deformed configurations in 100Zr and 240Pu by considering huge quasiparticle QRPA spaces. Our approach to FAM, based on Broyden's iterative procedure, opens the possibility for large-scale calculations of strength distributions in well-deformed superfluid nuclei across the nuclear landscape.

  13. Monopole Strength Function of Deformed Superfluid Nuclei

    SciTech Connect

    Stoitsov, M. V.; Kortelainen, E. M.; Nakatsukasa, T.; Losa, C.; Nazarewicz, Witold

    2011-01-01

    We present an efficient method for calculating strength functions using the finite amplitude method (FAM) for deformed superfluid heavy nuclei within the framework of the nuclear density functional theory. We demonstrate that FAM reproduces strength functions obtained with the fully self-consistent quasi-particle random-phase approximation (QRPA) at a fraction of computational cost. As a demonstration, we compute the isoscalar and isovector monopole strength for strongly deformed configurations in ^{240}Pu by considering huge quasi-particle QRPA spaces. Our approach to FAM, based on Broyden's iterative procedure, opens the possibility for large-scale calculations of strength distributions in well-bound and weakly bound nuclei across the nuclear landscape.

  14. β -decay study within multireference density functional theory and beyond

    NASA Astrophysics Data System (ADS)

    Konieczka, M.; Bączyk, P.; Satuła, W.

    2016-04-01

    A pioneering study of Gamow-Teller (GT) and Fermi matrix elements (MEs) using no-core-configuration-interaction formalism rooted in multireference density functional theory is presented. After a successful test performed for 6He→6Liβ decay, the model is applied to compute MEs in the s d - and p f -shell T =1 /2 mirror nuclei. The calculated GT MEs and the isospin-symmetry-breaking corrections to the Fermi branch are found to be in very good agreement with shell-model predictions in spite of fundamental differences between these models concerning model space, treatment of correlations, or inclusion of a core. This result indirectly supports the two-body-current-based scenarios behind the quenching of the axial-vector coupling constant.

  15. Study of gamma-ray strength functions

    SciTech Connect

    Gardner, D.G.; Gardner, M.A.; Dietrich, F.S.

    1980-08-07

    The use of gamma-ray strength function systematics to calculate neutron capture cross sections and capture gamma-ray spectra is discussed. The ratio of the average capture width, GAMMA/sub ..gamma../-bar, to the average level spacing, D/sub obs/, both at the neutron separation energy, can be derived from such systematics with much less uncertainty than from separate systematics for values of GAMMA/sub ..gamma../-bar and D/sub obs/. In particular, the E1 gamma-ray strength function is defined in terms of the giant dipole resonance (GDR). The GDR line shape is modeled with the usual Lorentzian function and also with a new energy-dependent, Breit-Wigner (EDBW) function. This latter form is further parameterized in terms of two overlapping resonances, even for nuclei where photonuclear measurements do not resolve two peaks. In the mass ranges studied, such modeling is successful for all nuclei away from the N = 50 closed neutron shell. Near the N = 50 shell, a one-peak EDBW appears to be more appropriate. Examples of calculated neutron capture excitation functions and capture gamma-ray spectra using the EDBW form are given for target nuclei in the mass-90 region and also in the Ta-Au mass region. 20 figures.

  16. Particle-vibration coupling effect on the β decay of magic nuclei.

    PubMed

    Niu, Y F; Niu, Z M; Colò, G; Vigezzi, E

    2015-04-10

    Nuclear β decay in magic nuclei is investigated, taking into account the coupling between particles and collective vibrations, on top of self-consistent random phase approximation calculations based on Skyrme density functionals. The low-lying Gamow-Teller strength is shifted downwards and at times becomes fragmented; as a consequence, the β-decay half-lives are reduced due to the increase of the phase space available for the decay. In some cases, this leads to a very good agreement between theoretical and experimental lifetimes: this happens, in particular, in the case of the Skyrme force SkM* that can also reproduce the line shape of the high-energy Gamow-Teller resonance as was previously shown.

  17. Particle-Vibration Coupling Effect on the β Decay of Magic Nuclei

    NASA Astrophysics Data System (ADS)

    Niu, Y. F.; Niu, Z. M.; Colò, G.; Vigezzi, E.

    2015-04-01

    Nuclear β decay in magic nuclei is investigated, taking into account the coupling between particles and collective vibrations, on top of self-consistent random phase approximation calculations based on Skyrme density functionals. The low-lying Gamow-Teller strength is shifted downwards and at times becomes fragmented; as a consequence, the β -decay half-lives are reduced due to the increase of the phase space available for the decay. In some cases, this leads to a very good agreement between theoretical and experimental lifetimes: this happens, in particular, in the case of the Skyrme force SkM* that can also reproduce the line shape of the high-energy Gamow-Teller resonance as was previously shown.

  18. Photon strength function of 97Zr

    NASA Astrophysics Data System (ADS)

    Mosby, Shea; Couture, Aaron; Lee, Hye Young

    2015-10-01

    Some of the major questions in stockpile stewardship require nuclear reaction rates on fission fragments where there are few or no experimental constraints. Theoretical calculations are an alternative, but their reliability is ultimately limited by our incomplete understanding of such physics inputs as the photon strength function. 96Zr lies near the light mass peak for 239Pu fission, and neutron capture on and near this nucleus is of great importance for applications. The DANCE array at LANSCE and the Apollo array coupled to HELIOS at Argonne National Laboratory offer complementary probes into the neutron capture reaction, and an experimental campaign is underway to study 96Zr(n, γ) and 96Zr(d , p) with these instruments. The status of these reaction studies will be presented.

  19. Systematics of strength function sum rules

    SciTech Connect

    Johnson, Calvin W.

    2015-08-28

    Sum rules provide useful insights into transition strength functions and are often expressed as expectation values of an operator. In this letter I demonstrate that non-energy-weighted transition sum rules have strong secular dependences on the energy of the initial state. Such non-trivial systematics have consequences: the simplification suggested by the generalized Brink–Axel hypothesis, for example, does not hold for most cases, though it weakly holds in at least some cases for electric dipole transitions. Furthermore, I show the systematics can be understood through spectral distribution theory, calculated via traces of operators and of products of operators. Seen through this lens, violation of the generalized Brink–Axel hypothesis is unsurprising: one expectssum rules to evolve with excitation energy. Moreover, to lowest order the slope of the secular evolution can be traced to a component of the Hamiltonian being positive (repulsive) or negative (attractive).

  20. Systematics of strength function sum rules

    DOE PAGES

    Johnson, Calvin W.

    2015-08-28

    Sum rules provide useful insights into transition strength functions and are often expressed as expectation values of an operator. In this letter I demonstrate that non-energy-weighted transition sum rules have strong secular dependences on the energy of the initial state. Such non-trivial systematics have consequences: the simplification suggested by the generalized Brink–Axel hypothesis, for example, does not hold for most cases, though it weakly holds in at least some cases for electric dipole transitions. Furthermore, I show the systematics can be understood through spectral distribution theory, calculated via traces of operators and of products of operators. Seen through this lens,more » violation of the generalized Brink–Axel hypothesis is unsurprising: one expectssum rules to evolve with excitation energy. Moreover, to lowest order the slope of the secular evolution can be traced to a component of the Hamiltonian being positive (repulsive) or negative (attractive).« less

  1. Gamow-Teller decay population of 64Ni levels in the decay of 1+ 64Co

    NASA Astrophysics Data System (ADS)

    Pauwels, D.; Radulov, D.; Walters, W. B.; Darby, I. G.; De Witte, H.; Diriken, J.; Fedorov, D. V.; Fedosseev, V. N.; Fraile, L. M.; Huyse, M.; Köster, U.; Marsh, B. A.; Popescu, L.; Seliverstov, M. D.; Sjödin, A. M.; Van den Bergh, P.; Van de Walle, J.; Van Duppen, P.; Venhart, M.; Wimmer, K.

    2012-12-01

    The 64Co β-decay feeding levels in the well-studied 64Ni nucleus were investigated. Whereas the previously known 64Co decay scheme merely contained 2 γ rays, the decay scheme established in this work contains 18, of which 5 are observed in this work and 6 were previously observed in an (n,γ) study but not placed in the 64Ni level scheme. Surprisingly, one additional level—placed at an excitation energy of 3578.7 keV—could be determined. The observed β-decay paths involve allowed νf5/2→πf7/2 and νp1/2→πp3/2 transitions. Three strongly fed levels around 4 MeV are interpreted to possess possible proton-intruder character.

  2. Updated Photonuclear Data Library and Database for Photon Strength Functions

    NASA Astrophysics Data System (ADS)

    Dimitriou, Paraskevi; Firestone, Richard B.; Siem, Sunniva; Bečvár, František; Krtička, Milan; Varlamov, Vladimir V.; Wiedeking, Mathis

    2015-05-01

    Photonuclear cross sections and gamma-ray data used to extract Photon Strength Functions are important for a large range of applications including basic sciences. The recommendations of an IAEA Consultant's Meeting to update the IAEA Photonuclear Data Library and create a Reference Database for Photon Strength Functions are presented.

  3. Photon Strength Function at Low Energies in 95Mo

    NASA Astrophysics Data System (ADS)

    Wiedeking, M.; Bernstein, L. A.; Allmond, J. M.; Basunia, M. S.; Bleuel, D. L.; Burke, J. T.; Fallon, P.; Firestone, R. B.; Goldblum, B. L.; Hatarik, R.; Krtička, M.; Lake, P. T.; Larsen, A. C.; Lee, I.-Y.; Lesher, S. R.; Paschalis, S.; Petri, M.; Phair, L.; Scielzo, N. D.

    2014-05-01

    A new and model-independent experimental method has been developed to determine the energy dependence of the photon strength function. It is designed to study statistical feeding from the quasi continuum to individual low-lying discrete levels. This new technique is presented and results for 95Mo are compared to data from the University of Oslo. In particular, questions regarding the existence of the low-energy enhancement in the photon strength function are addressed.

  4. Calculation Of Two Neutrino Double Beta Decay Nuclear Matrix Elements For 128,130Te

    SciTech Connect

    Uenlue, S.; Salamov, D. I.; Babacan, T.; Kuecuekbursa, A.

    2006-04-26

    Based on Pyatov-Salamov method, spin-isospin (Gamow-Teller) effective interaction strength parameter has been found self-consistently. Then, the problem has been solved within the framework of QRPA. Gamow-Teller matrix elements for both {beta}- and {beta}+ transitions and two neutrino double beta decay nuclear matrix elements have been calculated for 128,130Te{yields}128,130Xe transitions. The obtained results have been compared with the corresponding experimental data and other theoretical results.

  5. Functionalization enhancement on interfacial shear strength between graphene and polyethylene

    NASA Astrophysics Data System (ADS)

    Jin, Yikuang; Duan, Fangli; Mu, Xiaojing

    2016-11-01

    Pull-out processes were simulated to investigate the interfacial mechanical properties between the functionalized graphene sheet (FGS) and polyethylene (PE) matrix by using molecular dynamics simulation with ReaxFF reactive force field. The interfacial structure of polymer and the interfacial interaction in the equilibrium FGS/PE systems were also analyzed to reveal the enhancement mechanism of interfacial shear strength. We observed the insertion of functional groups into polymer layer in the equilibrium FGS/PE systems. During the pull-out process, some interfacial chains were attached on the FGS and pulled out from the polymer matrix. The behavior of these pulled out chains was further analyzed to clarify the different traction action of functional groups applied on them. The results show that the traction effect of functional groups on the pulled-out chains is agreement with their enhancement influence on the interfacial shear strength of the FGS/PE systems. They both are basically dominated by the size of functional groups, suggesting the enhancement mechanism of mechanical interlocking. However, interfacial binding strength also exhibits an obvious influence on the interfacial shear properties of the hybrid system. Our simulation show that geometric constrains at the interface is the principal contributor to the enhancement of interfacial shear strength in the FGS/PE systems, which could be further strengthened by the wrinkled morphology of graphene in experiments.

  6. Effects of hyperthyroidism on hand grip strength and function.

    PubMed

    Erkol İnal, Esra; Çarlı, Alparslan Bayram; Çanak, Sultan; Aksu, Oğuzhan; Köroğlu, Banu Kale; Savaş, Serpil

    2015-01-01

    Hyperthyroidism is a pathologic condition in which the body is exposed to excessive amounts of circulating thyroid hormones. Skeletal muscle is one of the major target organs of thyroid hormones. We evaluated hand grip strength and function in patients with overt hyperthyroidism. Fifty-one patients newly diagnosed with hyperthyroidism and 44 healthy controls participated in this study. Age, height, weight, and dominant hand of all participants were recorded. The diagnosis of hyperthyroidism was confirmed by clinical examination and laboratory tests. Hand grip strength was tested at the dominant hand with a Jamar hand dynamometer. The grooved pegboard test (PGT) was used to evaluate hand dexterity. The Duruöz Hand Index (DHI) was used to assess hand function. No significant differences were found in terms of clinical and demographic findings between the patients with hyperthyroidism and healthy controls (p > 0.05). Significant differences were found between the patients with hyperthyroidism and healthy controls regarding PGT and DHI scores (p < 0.05). Hyperthyroidism seemed to affect hand dexterity and function more than hand grip strength and seemed to be associated with reduced physical function more than muscle strength. This may also indicate that patients with hyperthyroidism should be evaluated by multidisplinary modalities.

  7. Effects of hyperthyroidism on hand grip strength and function.

    PubMed

    Erkol İnal, Esra; Çarlı, Alparslan Bayram; Çanak, Sultan; Aksu, Oğuzhan; Köroğlu, Banu Kale; Savaş, Serpil

    2015-01-01

    Hyperthyroidism is a pathologic condition in which the body is exposed to excessive amounts of circulating thyroid hormones. Skeletal muscle is one of the major target organs of thyroid hormones. We evaluated hand grip strength and function in patients with overt hyperthyroidism. Fifty-one patients newly diagnosed with hyperthyroidism and 44 healthy controls participated in this study. Age, height, weight, and dominant hand of all participants were recorded. The diagnosis of hyperthyroidism was confirmed by clinical examination and laboratory tests. Hand grip strength was tested at the dominant hand with a Jamar hand dynamometer. The grooved pegboard test (PGT) was used to evaluate hand dexterity. The Duruöz Hand Index (DHI) was used to assess hand function. No significant differences were found in terms of clinical and demographic findings between the patients with hyperthyroidism and healthy controls (p > 0.05). Significant differences were found between the patients with hyperthyroidism and healthy controls regarding PGT and DHI scores (p < 0.05). Hyperthyroidism seemed to affect hand dexterity and function more than hand grip strength and seemed to be associated with reduced physical function more than muscle strength. This may also indicate that patients with hyperthyroidism should be evaluated by multidisplinary modalities. PMID:26562373

  8. Stiffness and strength of oxygen-functionalized graphene with vacancies

    SciTech Connect

    Zandiatashbar, A.; Ban, E.; Picu, R. C.

    2014-11-14

    The 2D elastic modulus (E{sup 2D}) and strength (σ{sup 2D}) of defective graphene sheets containing vacancies, epoxide, and hydroxyl functional groups are evaluated at 300 K by atomistic simulations. The fraction of vacancies is controlled in the range 0% to 5%, while the density of functional groups corresponds to O:C ratios in the range 0% to 25%. In-plane modulus and strength diagrams as functions of vacancy and functional group densities are generated using models with a single type of defect and with combinations of two types of defects (vacancies and functional groups). It is observed that in models containing only vacancies, the rate at which strength decreases with increasing the concentration of defects is largest, followed by models containing only epoxide groups and those with only hydroxyl groups. The effect on modulus of vacancies and epoxides present alone in the model is similar, and much stronger than that of hydroxyl groups. When the concentration of defects is large, the combined effect of the functional groups and vacancies cannot be obtained as the superposition of individual effects of the two types of defects. The elastic modulus deteriorates faster (slower) than predicted by superposition in systems containing vacancies and hydroxyl groups (vacancies and epoxide groups)

  9. A NEW CLINICAL MUSCLE FUNCTION TEST FOR ASSESSMENT OF HIP EXTERNAL ROTATION STRENGTH: AUGUSTSSON STRENGTH TEST

    PubMed Central

    2016-01-01

    ABSTRACT Introduction Dynamic clinical tests of hip strength applicable on patients, non–athletes and athletes alike, are lacking. The aim of this study was therefore to develop and evaluate the reliability of a dynamic muscle function test of hip external rotation strength, using a novel device. A second aim was to determine if gender differences exist in absolute and relative hip strength using the new test. Methods Fifty–three healthy sport science students (34 women and 19 men) were tested for hip external rotation strength using a device that consisted of a strap connected in series with an elastic resistance band loop, and a measuring tape connected in parallel with the elastic resistance band. The test was carried out with the subject side lying, positioned in 45 ° of hip flexion and the knees flexed to 90 ° with the device firmly fastened proximally across the knees. The subject then exerted maximal concentric hip external rotation force against the device thereby extending the elastic resistance band. The displacement achieved by the subject was documented by the tape measure and the corresponding force production was calculated. Both right and left hip strength was measured. Fifteen of the subjects were tested on repeated occasions to evaluate test–retest reliability. Results No significant test–retest differences were observed. Intra–class correlation coefficients ranged 0.93–0.94 and coefficients of variation 2.76–4.60%. In absolute values, men were significantly stronger in hip external rotation than women (right side 13.2 vs 11.0 kg, p = 0.001, left side 13.2 vs 11.5 kg, p = 0.002). There were no significant differences in hip external rotation strength normalized for body weight (BW) between men and women (right side 0.17 kg/BW vs 0.17 kg/BW, p = 0.675, left side 0.17 kg/BW vs 0.18 kg/BW, p = 0.156). Conclusions The new muscle function test showed high reliability and thus could be useful for measuring dynamic hip

  10. Functional organization of excitatory synaptic strength in primary visual cortex

    PubMed Central

    Muir, Dylan R.; Houlton, Rachael; Sader, Elie N.; Ko, Ho; Hofer, Sonja B.; Mrsic-Flogel, Thomas D.

    2016-01-01

    The strength of synaptic connections fundamentally determines how neurons influence each other’s firing. Excitatory connection amplitudes between pairs of cortical neurons vary over two orders of magnitude, comprising only very few strong connections among many weaker ones1–9. Although this highly skewed distribution of connection strengths is observed in diverse cortical areas1–9, its functional significance remains unknown: it is not clear how connection strength relates to neuronal response properties, nor how strong and weak inputs contribute to information processing in local microcircuits. Here we reveal that the strength of connections between layer 2/3 (L2/3) pyramidal neurons in mouse primary visual cortex (V1) obeys a simple rule—the few strong connections occur between neurons with most correlated responses, while only weak connections link neurons with uncorrelated responses. Moreover, we show that strong and reciprocal connections occur between cells with similar spatial receptive field structure. Although weak connections far outnumber strong connections, each neuron receives the majority of its local excitation from a small number of strong inputs provided by the few neurons with similar responses to visual features. By dominating recurrent excitation, these infrequent yet powerful inputs disproportionately contribute to feature preference and selectivity. Therefore, our results show that the apparently complex organization of excitatory connection strength reflects the similarity of neuronal responses, and suggest that rare, strong connections mediate stimulus-specific response amplification in cortical microcircuits. PMID:25652823

  11. Evaluation of prosodic juncture strength using functional data analysis

    PubMed Central

    Parrell, Benjamin; Lee, Sungbok; Byrd, Dani

    2013-01-01

    Prosodic structure has large effects on the temporal realization of speech via the shaping of articulatory events. It is important for speech scientists to be able to systematically quantify these prosodic effects on articulation in a way that is capable both of differentiating between the degree of prosodic lengthening associated with varying linguistic contexts and that is generalizable across speakers. The current paper presents a novel method to automatically quantify boundary strength from articulatory speech data based on functional data analysis (FDA). In particular, a new derived variable—the Deformation Index—is proposed, which is the area under FDA time-deformation functions. First using synthetic speech produced with the TaDA task dynamics computational model, the Deformation Index is shown to be able to capture a priori known differences in boundary strengths instantiated in the π-gesture framework. Additionally, this method accurately distinguishes between types of boundaries in non-synthetic speech produced by four speakers. PMID:24244056

  12. Effect of expiratory muscle strength training on elderly cough function.

    PubMed

    Kim, Jaeock; Davenport, Paul; Sapienza, Christine

    2009-01-01

    Age-related loss of muscle strength, known as sarcopenia, in the expiratory muscles, along with reductions in lung elastic recoil and chest wall compliance decreases the intrathoacic airway pressure as well as expiratory flow rates and velocity, greatly impacting an elderly person's ability to generate the forces essential for cough. This study examined the effects of a 4-week expiratory muscle strength training (EMST) program on maximum expiratory pressure (MEP) and cough function in 18 healthy but sedentary elderly adults. MEP significantly increased after the EMST program from 77.14+/-20.20 to 110.83+/-26.11cmH(2)O. Parameters measured during reflexive coughs produced by capsaicin challenge, indicated that compression phase duration significantly decreased (from 0.35+/-0.19 to 0.16+/-0.17s), peak expiratory flow rate decreased (from 4.98+/-2.18 to 8.00+/-3.05l/s) and post-peak plateau integral amplitude significantly increased (from 3.49+/-2.46 to 6.83+/-4.16l/ss) with the EMST program. EMST seems to be an effective program to increase the expiratory muscle strength in the sedentary elderly, which contribute to an enhanced cough function. PMID:18457885

  13. Assessment of grip strength with the modified sphygmomanometer test: association between upper limb global strength and motor function

    PubMed Central

    Martins, Júlia C.; Aguiar, Larissa T.; Lara, Eliza M.; Teixeira-Salmela, Luci F.; Faria, Christina D. C. M.

    2015-01-01

    ABSTRACT Background: Grip strength, commonly evaluated with the handgrip dynamometer, is a good indicator of upper limb (UL) function in stroke subjects and may reflect the global strength deficits of the whole paretic UL. The Modified Sphygmomanometer Test (MST) also provides objective and adequate measures at low-cost. Objective: To assess whether grip strength values obtained by using the MST and those obtained by using a handgrip dynamometer would present similar correlations with the global strength and motor function of the paretic UL in subjects with stroke, both in the subacute and chronic phases. Method: Measures of grip strength (MST and handgrip dynamometer), UL global strength (MST and hand-held dynamometer), and UL motor function (Fugl-Meyer motor assessment scale) were obtained with 33 subacute and 44 chronic stroke subjects. Pearson and Spearman correlation coefficients were calculated and Stepwise multiple regression analyses were performed to investigate predictor variables of grip strength (α=0.05). Results: Significant correlations of similar magnitude were found between measures of global strength of the paretic UL and grip strength assessed with both the MST (0.66≤r≤0.78) and handgrip dynamometer (0.66≤r≤0.78) and between UL motor function and grip strength assessed with both the MST (0.50≤rs≤0.51) and hand-held dynamometer (0.50≤rs≤0.63) in subacute and chronic stroke subjects. Only global strength remained as a significant predictor variable of grip strength for the MST (0.43≤R2≤0.61) and for the handgrip dynamometer (0.44≤R2≤0.61) for both stroke subgroups. Conclusion: Grip strength assessed with the MST could be used to report paretic UL global strength. PMID:26647752

  14. Investigating the Photon Strength Function to Discrete Levels

    NASA Astrophysics Data System (ADS)

    Wiedeking, M.; Bernstein, L. A.; Bleuel, D. L.; Burke, J. T.; Hatarik, R.; Lesher, S. R.; Scielzo, N. D.; Krtička, M.; Allmond, J. M.; Basunia, M. S.; Fallon, P.; Firestone, R. B.; Goldblum, B. L.; Lake, P. T.; Lee, I.-Y.; Paschalis, S.; Petri, M.; Phair, L.

    2015-11-01

    Over the last decade several measurements in medium mass nuclei have reported a low-energy enhancement in the photon strength function. Although, much effort has been invested in unravelling the mysteries of this effect, its physical origin is still not understood. Here, a completely model-independent experimental approach to investigate the possible existence of this enhancement is presented. The experiment was designed to study statistical feeding from the quasi-continuum (below the neutron separation energy) to individual low-lying discrete levels in 95Mo produced in the (d,p) reaction. A key aspect to successfully study gamma decay from the region of high level-density is the detection and extraction of correlated particle-gamma-gamma events which was accomplished using an array of Clover HPGe detectors and large area annular silicon detectors. The entrance channel excitation energy into the residual nucleus produced in the reaction was inferred from the detected proton energies in the silicon detectors. Gating on gamma-transitions originating from low-lying discrete levels specifies the state fed by statistical gamma-rays. Any particle-gamma-gamma event in combination with specific energy sum requirements ensures a clean and unambiguous determination of the initial and final state of the observed gamma rays. With these requirements the statistical feeding to individual discrete levels is extracted on an event-by-event basis. The latest results are presented and compared to 95Mo photon strength function data measured at the University of Oslo by Guttormsen et al. In particular, questions regarding the existence of the low-energy enhancement in the photon strength function are addressed.

  15. Radiative strength functions in {sup 163,164}Dy

    SciTech Connect

    Nyhus, H. T.; Siem, S.; Guttormsen, M.; Larsen, A. C.; Buerger, A.; Syed, N. U. H.; Tveten, G. M.; Voinov, A.

    2010-02-15

    The nuclei {sup 163,164}Dy have been investigated using the Oslo method on data from the pickup reaction {sup 164}Dy({sup 3}He,{alpha}{gamma}){sup 163}Dy and the inelastic scattering {sup 164}Dy({sup 3}He,{sup 3}He{sup '}{gamma}){sup 164}Dy, respectively. The radiative strength functions for both nuclei have been extracted, and a small resonance centered around E{sub {gamma}}approx =3 MeV is observed in both cases. The parameters of this so-called pygmy M1 resonance (the scissors mode) are compared with previous results on {sup 160,161,162}Dy using the Oslo method, and with data on {sup 163}Dy measured by the Prague group using the two-step cascade method. In particular, the integrated reduced transition probability B(M1arrow up) of the pygmy resonance is compared with neighboring dysprosium isotopes. We also observe an enhanced strength in the region above E{sub {gamma}}approx =5 MeV in {sup 164}Dy. Possible origins of this feature are discussed.

  16. Dielectronic recombination as a function of electric field strength

    NASA Technical Reports Server (NTRS)

    Reisenfeld, Daniel B.

    1992-01-01

    Dielectronic recombination (DR) is the dominant recombination mechanism at coronal temperatures and densities. We present a procedure for calculating DR rate coefficients as a function of electric field strength and apply this method to carbon ions. We focus on the competing effects of enhancement by plasma microfields and rate decrease through collisional excitation and ionization. We find that, in the case of C(3+), a significant rate enhancement results, leading to a reinterpretation of C IV emission-line intensities in the sun and late-type stars. We further consider how macroscopic electric fields, in particular motional electric fields, can affect DR rate coefficients, demonstrating dramatic rate increases for a number of the carbon ions.

  17. Is there a low-energy enhancement in the photon strength function in molybdenum?

    NASA Astrophysics Data System (ADS)

    Sheets, S. A.

    2008-04-01

    Recent claims of a low-energy enhancement in the photon strength function of 96Mo are investigated. Using the DANCE detector the gamma-ray spectra following resonance neutron capture was measured. The spectrum fitting method was used to indirectly extract a photon strength function from the gamma-ray spectra. No strong low energy enhancement in the photon strength function was found.

  18. Is there a low energy enhancement in the photon strength function in molybdenum?

    SciTech Connect

    Sheets, S A

    2008-01-30

    Recent claims of a low energy enhancement in the photon strength function of {sup 96}Mo are investigated. Using the DANCE detector the gamma-ray spectra following resonance neutron capture was measured. The spectrum fitting method was used to indirectly extract a photon strength function from the gamma-ray spectra. No strong low energy enhancement in the photon strength function was found.

  19. Photon Strength Functions below GDER Maximum: Present Status and Outlook

    SciTech Connect

    Krticka, Milan

    2009-01-28

    Existing experimental data on {gamma} decay of energy levels in medium-weight and heavy nuclei at excitation energies well above the pairing gap indicate that the role of nuclear structure effects is small and that this decay is largely governed by the extreme statistical model. Specifically, in line with the validity of Brink hypothesis and the paradigm of photon strength, the average properties of the {gamma} decay can be described by a set of photon strength functions (PSFs) for individual multipolarities and by the level density function. PSFs are directly related to the photoabsorption cross sections {sigma}{sub {gamma}}{sub abs}. It is well known that in the case of E1 radiation this cross section is dominated by the giant dipole electric resonance. However the size of {sigma}{sub {gamma}}{sub abs.} and its {gamma}-ray energy dependence at energies below the neutron threshold are known rather poorly. In the case of higher multipolarities (M1, E2,...) the present knowledge about their roles is much worse. Available information on E1 and M1 PSFs obtained from various kinds of experiments in the {gamma}-ray energy region of interest will be discussed within the widely used models. It will be shown that none of them seems to be able to describe PSFs reasonably for a broad range of nuclei. Emphasis will be also laid on the properties of the scissors mode and other possible resonance-like structures in PSFs at energies below about 10 MeV. Perspectives of further studies of PSFs will be outlined.

  20. A new Skyrme energy density functional for a better description of spin-isospin resonances

    NASA Astrophysics Data System (ADS)

    Roca-Maza, X.; Colò, G.; Cao, Li-Gang; Sagawa, H.

    2015-10-01

    A correct determination of the isospin and spin-isospin properties of the nuclear effective interaction should lead to an accurate description of the Gamow-Teller resonance (GT), the Spin Dipole Resonance (SDR), the Giant Dipole Resonance (GDR) or the Antianalog Giant Dipole Resonance (AGDR), among others. A new Skyrme energy density functional named SAMi is introduced with the aim of going a step forward in setting the bases for a more precise description of spin-isospin resonances [1, 2]. In addition, we will discuss some new features of our analysis on the AGDR in 208Pb [3] as compared with available experimental data on this resonance [4, 5, 6], and on the GDR [7]. Such study, guided by a simple yet physical pocket formula, has been developed by employing the so called SAMi-J family of systematically varied interactions. This set of interactions is compatible with experimental data for values of the symmetry energy at saturation J and slope parameter L falling in the ranges 31-33 MeV and 75-95 MeV, respectively.

  1. A new Skyrme energy density functional for a better description of spin-isospin resonances

    SciTech Connect

    Roca-Maza, X.; Colò, G.; Cao, Li-Gang; Sagawa, H.

    2015-10-15

    A correct determination of the isospin and spin-isospin properties of the nuclear effective interaction should lead to an accurate description of the Gamow-Teller resonance (GT), the Spin Dipole Resonance (SDR), the Giant Dipole Resonance (GDR) or the Antianalog Giant Dipole Resonance (AGDR), among others. A new Skyrme energy density functional named SAMi is introduced with the aim of going a step forward in setting the bases for a more precise description of spin-isospin resonances [1, 2]. In addition, we will discuss some new features of our analysis on the AGDR in {sup 208}Pb [3] as compared with available experimental data on this resonance [4, 5, 6], and on the GDR [7]. Such study, guided by a simple yet physical pocket formula, has been developed by employing the so called SAMi-J family of systematically varied interactions. This set of interactions is compatible with experimental data for values of the symmetry energy at saturation J and slope parameter L falling in the ranges 31−33 MeV and 75−95 MeV, respectively.

  2. {beta}-decay in neutron-deficient Hg, Pb, and Po isotopes

    SciTech Connect

    Moreno, O.; Sarriguren, P.; Alvarez-Rodriguez, R.; Guerra, E. Moya de

    2006-05-15

    The effect of nuclear deformation on the energy distributions of the Gamow-Teller strength is studied in neutron-deficient Hg, Pb, and Po even isotopes. The theoretical framework is based on a self-consistent deformed Skyrme Hartree-Fock mean field with pairing correlations between like nucleons in BCS approximation and residual spin-isospin interactions treated in the proton-neutron quasiparticle random-phase approximation. After a systematic study of the Gamow-Teller strength distributions in the low-excitation-energy region, relevant for {beta}{sup +} decay, we have identified the best candidates to look for deformation signatures in their {beta}{sup +}-decay patterns. {beta}{sup +} half-lives and total Gamow-Teller strengths B(GT{sup {+-}}) are analyzed as well.

  3. Is there a low-energy enhancement in the photon strength function in molybdenum?

    SciTech Connect

    Sheets, S. A.

    2008-04-17

    Recent claims of a low-energy enhancement in the photon strength function of {sup 96}Mo are investigated. Using the DANCE detector the gamma-ray spectra following resonance neutron capture was measured. The spectrum fitting method was used to indirectly extract a photon strength function from the gamma-ray spectra. No strong low energy enhancement in the photon strength function was found.

  4. Determination of functional strength imbalance of the lower extremities.

    PubMed

    Newton, Robert U; Gerber, Aimee; Nimphius, Sophia; Shim, Jae K; Doan, Brandon K; Robertson, Mike; Pearson, David R; Craig, Bruce W; Häkkinen, Keijo; Kraemer, William J

    2006-11-01

    The purposes of this study were (a) to determine whether a significant strength imbalance existed between the left and right or dominant (D) and nondominant (ND) legs and (b) to investigate possible correlations among various unilateral and bilateral closed kinetic chain tests, including a field test, and traditional isokinetic dynamometry used to determine strength imbalance. Fourteen Division I collegiate women softball players (20.2 +/- 1.4 years) volunteered to undergo measures of average peak torque for isokinetic flexion and extension at 60 degrees .s(-1) and 240 degrees .s(-1); in addition, measures of peak and average force of each leg during parallel back squat, 2-legged vertical jump, and single-leg vertical jump and performance in a 5-hop test were examined. Significant differences of between 4.2% and 16.0% were evident for all measures except for average force during single-leg vertical jump between the D and ND limbs, thus revealing a significant strength imbalance. The 5-hop test revealed a significant difference between D and ND limbs and showed a moderate correlation with more sophisticated laboratory tests, suggesting a potential use as a field test for the identification of strength imbalance. The results of this study indicate that a significant strength imbalance can exist even in collegiate level athletes, and future research should be conducted to determine how detrimental these imbalances could be in terms of peak performance for athletes, as well as the implications for injury risk.

  5. Metamaterial magnetoinductive lens performance as a function of field strength.

    PubMed

    Algarín, José M; Freire, Manuel J; Breuer, Felix; Behr, Volker C

    2014-10-01

    Metamaterials are artificial composites that exhibit exotic electromagnetic properties, as the ability of metamaterial slabs to behave like lenses with sub-wavelength resolution for the electric or the magnetic field. In previous works, the authors investigated magnetic resonance imaging (MRI) applications of metamaterial slabs that behave like lenses for the radiofrequency magnetic field. In particular, the authors investigated the ability of MRI metamaterial lenses to increase the signal-to-noise ratio (SNR) of surface coils, and to localize the field of view (FOV) of the coils, which is of interest for parallel MRI (pMRI) applications. A metamaterial lens placed between a surface coil and the tissue enhances the sensitivity of the coil. Although the metamaterial lens introduces losses which add to the losses of the tissue, the enhancement of the sensitivity can compensate these additional losses and the SNR of the coil is increased. In a previous work, an optimization procedure was followed to find a metamaterial structure with minimum losses that will maximize the SNR. This structure was termed magnetoinductive (MI) lens by the authors. The properties of surface coils in the presence of MI lenses were investigated in previous works at the proton frequency of 1.5 T systems. The different frequency dependence of the losses in both the MI lenses and the tissue encouraged us to investigate the performance of MI lenses at different frequencies. Thus, in the present work, the SNR and the pMRI ability of MI lenses are investigated as a function of field strength. A numerical analysis is carried out with an algorithm developed by the authors to predict the SNR behavior of a surface coil loaded with a MI lens at the proton frequencies of 0.5 T, 1.5 T and 3 T systems. The results show that, at 0.5 T, there is a gain in the SNR for short distances, but the SNR is highly degraded at deeper distances. However, at 1.5 T and 3T, the MI lenses provide a gain in the SNR up to a

  6. The Spectroscopic study of {sup 33}Ar

    SciTech Connect

    Adimi, N.; Dominguez-Reyes, R.; Alcorta, M.; Borge, M. J. G.; Perea, A.; Tengblad, O.; Bey, A.; Blank, B.; Dossat, C.; Giovinazzo, J.; Matea, I.; Fynbo, H. O. U.; Knudsen, H. H.; Suemmerer, K.

    2011-10-28

    The proton-rich nucleus {sup 33}Ar has been produced at the low-energy facility SPIRAL at GANIL. Spectroscopic studies of gamma and p emission of this nucleus were performed with the 'Silicon Cube' detection system. The analysis of proton and gamma singles and coincidence spectra allowed us to establish a complete decay scheme of this nucleus. The comparison of the Gamow-Teller strength distribution deduced from our experiment and the theoretical one obtained with the Shell Model permitted the determination of a quenching factor for the Gamow-Teller strength.

  7. The relationship between knee strength and functional stability before and after anterior cruciate ligament reconstruction.

    PubMed

    Keays, S L; Bullock-Saxton, J E; Newcombe, P; Keays, A C

    2003-03-01

    Functional stability of the knee is dependent on an intact ligamentous system and the timely and efficient contraction of supporting musculature. The aim of this study was to assess the relationship between muscle strength and functional stability in 31 patients pre- and post-operatively, following a unilateral anterior cruciate ligament rupture. All subjects underwent reconstructive surgery using semitendonosis and gracilis tendons. Isokinetic strength assessment of quadriceps and hamstring muscles was performed at a rate of movement of 60 degrees /s and 120 degrees /s. Functional stability was determined by performance during five functional stability tests that included the shuttle run, side step, carioca, single and triple hop tests. Pearson's correlation coefficient statistics were applied to pre-operative and post-operative data respectively. These analyses demonstrated a significant positive correlation between quadriceps strength indices at both testing speeds and the two hop tests pre-operatively (p's<0.007) and between quadriceps strength indices at both speeds and all five functional tests post-operatively (p's<0.01). Assessed using Steiger's formula, there was a significant increase in the correlation between quadriceps strength indices and three functional tests post-operatively compared to pre-operatively (p<0.05). No significant correlation between hamstring strength indices and functional scores existed pre- or post-operatively. This study has shown a significant correlation exists between quadriceps strength indices and functional stability both before and after surgery, this relationship does not reach significance between hamstring strength indices and functional stability.

  8. Properties of Shell-Model Wavefunctions at High Excitation Energies

    NASA Astrophysics Data System (ADS)

    Frazier, Njema Jioni

    Within the framework of the nuclear shell model with a realistic residual hamiltonian one can obtain the exact solution of the many-body problem. This makes it possible to study the interrelation between regular and chaotic features of dynamics in a generic many-body system with strong interaction. As an important application, we analyse the fragmentation of simple configurations as a function of excitation energy and interaction strength and examine the transition strengths induced by simple operators as a function of excitation energy. The analysis is performed for two systems; that of 12 valence particles in the sd-shell, or 28Si, and that of 8 valence particles in the sd-shell, or 24Mg. For the system of 12 valence particles in the sd-shell, we examine the fragmentation of shell-model basis states. For the system of 8 valence nucleons in the sd-shell, we examine the fragmentation associated with single-nucleon transfer and Gamow-Teller transitions. For the fragmentation of basis states, we use our statistics to establish the generic shape of the strength function distribution in the region of strong mixing. For the realistic interaction, the strength function distribution is close to Gaussian in the central part of the energy spectra. The width of the distribution is larger than predicted by Fermi's golden rule (4). We then take this one step further and examine the strength distributions associated with the one-nucleon transfer operator, aλ†, and the Gamow-Teller (GT) operator, Σλλ'(σμ τ±) λλ'aλ†a λ'. The spectroscopic factor, which is proportional to the square of the matrix element for the aλ† operator, is the simplest quantity used in predicting experimental observables. In our discussion of Gamow-Teller transitions, we examine both the GT strength function distribution and the values of total strength B(GT). For all the cases we examine, we take advantage of the reliability of our model for low-lying levels and our statistics to explore

  9. Do changes in hand grip strength correlate with shoulder rotator cuff function?

    PubMed Central

    Herrington, Lee; Hoyle, Rebecca; Prescott, Evie; Bellamy, Nathan

    2016-01-01

    Background Shoulder pain as a result of rotator cuff pathology is one of the most common musculoskeletal complaints presenting within primary care. Assessment of hand grip strength has been proposed as an indicator of rotator cuff function. This experimental study assessed the relationship between grip strength and shoulder lateral rotator muscle strength in a number of different shoulder positions, aiming to investigate whether such a relationship existed and whether grip strength could be used as a functional assessment tool for the posterior cuff. Methods Twenty-seven healthy, physically active, volunteers (19 males, eight females) with no history of shoulder, upper limb or neck injury comprised the study group. The mean (SD) age was 19.8 (5.7) years (range 18 years to 23 years). Grip strength (measured with hand grip dynamometer) and lateral rotator strength (measured with a hand held dynamometer) was measured at neutral, 90° abduction, and 90° abduction with 90° external rotation. Results The correlation between grip strength and shoulder lateral rotation strength ranged between r = 0.91 (r2 = 0.84) and r = 0.72 (r2 = 0.52) across all positions. Conclusions A strong correlation between grip strength and lateral rotator strength was shown at all positions for both left and right hands, suggesting that assessment of grip strength could be used as a rotator cuff monitor of recruitment function. PMID:27583010

  10. Radiative strength functions for dipole transitions in {sup 90}Zr

    SciTech Connect

    Fedorets, I. D. Ratkevich, S. S.

    2013-01-15

    Partial cross sections for the (p, {gamma}) reaction on the {sup 89}Y nucleus that were measured previously at proton energies between 2.17 and 5.00 MeV and which were averaged over resonances were used to determine the absolute values and the energy distribution of the strength of dipole transitions from compound-nucleus states to low-lying levels of the {sup 90}Zr nucleus. The data obtained in this way were compared with the predictions of various models.

  11. Handgrip Strength Predicts Functional Decline at Discharge in Hospitalized Male Elderly: A Hospital Cohort Study

    PubMed Central

    García-Peña, Carmen; García-Fabela, Luis C.; Gutiérrez-Robledo, Luis M.; García-González, Jose J.; Arango-Lopera, Victoria E.; Pérez-Zepeda, Mario U.

    2013-01-01

    Functional decline after hospitalization is a common adverse outcome in elderly. An easy to use, reproducible and accurate tool to identify those at risk would aid focusing interventions in those at higher risk. Handgrip strength has been shown to predict adverse outcomes in other settings. The aim of this study was to determine if handgrip strength measured upon admission to an acute care facility would predict functional decline (either incident or worsening of preexisting) at discharge among older Mexican, stratified by gender. In addition, cutoff points as a function of specificity would be determined. A cohort study was conducted in two hospitals in Mexico City. The primary endpoint was functional decline on discharge, defined as a 30-point reduction in the Barthel Index score from that of the baseline score. Handgrip strength along with other variables was measured at initial assessment, including: instrumental activities of daily living, cognition, depressive symptoms, delirium, hospitalization length and quality of life. All analyses were stratified by gender. Logistic regression to test independent association between handgrip strength and functional decline was performed, along with estimation of handgrip strength test values (specificity, sensitivity, area under the curve, etc.). A total of 223 patients admitted to an acute care facility between 2007 and 2009 were recruited. A total of 55 patients (24.7%) had functional decline, 23.46% in male and 25.6% in women. Multivariate analysis showed that only males with low handgrip strength had an increased risk of functional decline at discharge (OR 0.88, 95% CI 0.79–0.98, p = 0.01), with a specificity of 91.3% and a cutoff point of 20.65 kg for handgrip strength. Females had not a significant association between handgrip strength and functional decline. Measurement of handgrip strength on admission to acute care facilities may identify male elderly patients at risk of having functional decline, and

  12. Interfacial Strength and Physical Properties of Functionalized Graphene - Epoxy Nanocomposites

    NASA Technical Reports Server (NTRS)

    Miller, Sandi G.; Heimann, Paula; Scheiman, Daniel; Adamson, Douglas H.; Aksay, Iihan A.; Prud'homme, Robert K.

    2006-01-01

    The toughness and coefficient of thermal expansion of a series of functionalized graphene sheet - epoxy nanocomposites are investigated. Functionalized graphene sheets are produced by splitting graphite oxide into single graphene sheets through a rapid thermal expansion process. These graphene sheets contain approx. 10% oxygen due to the presence of hydroxide, epoxide, and carboxyl functional groups which assist in chemical bond formation with the epoxy matrix. Intrinsic surface functionality is used to graft alkyl amine chains on the graphene sheets, and the addition of excess hardener insures covalent bonding between the epoxide matrix and graphene sheets. Considerable improvement in the epoxy dimensional stability is obtained. An increase in nanocomposite toughness is observed in some cases.

  13. Comparitive Assessment of Isokinetic and Pneumatic Lower Limb Strength in Functionally-Limited Elderly Subjects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of this study was to investigate the relationship between isokinetic and pneumatic knee extensor strength in functionally-limited elders and to compare the respective changes in knee extensor peak torque and one repetition maximum strength (1RM) after a randomized controlled progressive ...

  14. The Resilience Function of Character Strengths in the Face of War and Protracted Conflict

    PubMed Central

    Shoshani, Anat; Slone, Michelle

    2016-01-01

    This study investigated the role of character strengths and virtues in moderating relations between conflict exposure and psychiatric symptoms among 1078 adolescents aged 13–15 living in southern Israel, who were exposed to lengthy periods of war, terrorism and political conflict. Adolescents were assessed for character strengths and virtues, political violence exposure using the Political Life Events (PLE) scale, and psychiatric symptoms using the Brief Symptom Inventory and the UCLA PTSD Index. Results confirmed that political violence exposure was positively correlated with psychiatric symptoms. Interpersonal, temperance and transcendence strengths were negatively associated with psychiatric symptoms. Moderating effects of the interpersonal strengths on the relation between political violence exposure and the psychiatric and PTSD indices were confirmed. The findings extend existing knowledge about the resilience function of character strengths in exposure to protracted conflict and have important practical implications for applying strength-building practices for adolescents who grow up in war-affected environments. PMID:26793139

  15. Effects of acute physical exercise on executive functions: a comparison between aerobic and strength exercise.

    PubMed

    Alves, Christiano Rodrigues; Gualano, Bruno; Takao, Pollyana Pereira; Avakian, Paula; Fernandes, Rafael Mistura; Morine, Diego; Takito, Monica Yuri

    2012-08-01

    The aim of this study was to compare the effects of acute aerobic and strength exercises on selected executive functions. A counterbalanced, crossover, randomized trial was performed. Forty-two healthy women were randomly submitted to three different conditions: (1) aerobic exercise, (2) strength exercise, and (3) control condition. Before and after each condition, executive functions were measured by the Stroop Test and the Trail Making Test. Following the aerobic and strength sessions, the time to complete the Stroop "non-color word" and "color word" condition was lower when compared with that of the control session. The performance in the Trail Making Test was unchanged. In conclusion, both acute aerobic and strength exercises improve the executive functions. Nevertheless, this positive effect seems to be task and executive function dependent. PMID:22889693

  16. Upper extremity muscle volumes and functional strength after resistance training in older adults.

    PubMed

    Daly, Melissa; Vidt, Meghan E; Eggebeen, Joel D; Simpson, W Greg; Miller, Michael E; Marsh, Anthony P; Saul, Katherine R

    2013-04-01

    Aging leads to a decline in strength and an associated loss of independence. The authors examined changes in muscle volume, maximum isometric joint moment, functional strength, and 1-repetition maximum (1RM) after resistance training (RT) in the upper extremity of older adults. They evaluated isometric joint moment and muscle volume as predictors of functional strength. Sixteen healthy older adults (average age 75 ± 4.3 yr) were randomized to a 6-wk upper extremity RT program or control group. The RT group increased 1RM significantly (p < .01 for all exercises). Compared with controls, randomization to RT led to greater functional pulling strength (p = .003), isometric shoulder-adduction moment (p = .041), elbow-flexor volume (p = .017), and shoulder-adductor volume (p = .009). Shoulder-muscle volumes and isometric moments were good predictors of functional strength. The authors conclude that shoulder strength is an important factor for performing functional reaching and pulling tasks and a key target for upper extremity RT interventions. PMID:22952203

  17. Upper extremity muscle volumes and functional strength after resistance training in older adults.

    PubMed

    Daly, Melissa; Vidt, Meghan E; Eggebeen, Joel D; Simpson, W Greg; Miller, Michael E; Marsh, Anthony P; Saul, Katherine R

    2013-04-01

    Aging leads to a decline in strength and an associated loss of independence. The authors examined changes in muscle volume, maximum isometric joint moment, functional strength, and 1-repetition maximum (1RM) after resistance training (RT) in the upper extremity of older adults. They evaluated isometric joint moment and muscle volume as predictors of functional strength. Sixteen healthy older adults (average age 75 ± 4.3 yr) were randomized to a 6-wk upper extremity RT program or control group. The RT group increased 1RM significantly (p < .01 for all exercises). Compared with controls, randomization to RT led to greater functional pulling strength (p = .003), isometric shoulder-adduction moment (p = .041), elbow-flexor volume (p = .017), and shoulder-adductor volume (p = .009). Shoulder-muscle volumes and isometric moments were good predictors of functional strength. The authors conclude that shoulder strength is an important factor for performing functional reaching and pulling tasks and a key target for upper extremity RT interventions.

  18. E1 and M1 γ-strength functions in 144Nd

    DOE PAGES

    Voinov, A. V.; Grimes, S. M.

    2015-12-14

    Both E1 and M1 γ-strength functions below the neutron separation energy were analyzed based on experimental data from 143Nd(n,γ)144Nd and 143Nd(n,γα)140Ce reactions. It is confirmed that the commonly adopted E1 model based on the temperature dependence of the width of the giant dipole resonance works well. The popular M1 strength function due to the spin-flip magnetic resonance located near the neutron binding energy is not capable of reproducing experimental data. As a result, the low-energy enhancement of the M1 strength or the energy-independent model of Weisskopf, both leading to the low-energy strength sizable to E1 one, fit experimental data best.

  19. E1 and M1 γ-strength functions in 144Nd

    SciTech Connect

    Voinov, A. V.; Grimes, S. M.

    2015-12-14

    Both E1 and M1 γ-strength functions below the neutron separation energy were analyzed based on experimental data from 143Nd(n,γ)144Nd and 143Nd(n,γα)140Ce reactions. It is confirmed that the commonly adopted E1 model based on the temperature dependence of the width of the giant dipole resonance works well. The popular M1 strength function due to the spin-flip magnetic resonance located near the neutron binding energy is not capable of reproducing experimental data. As a result, the low-energy enhancement of the M1 strength or the energy-independent model of Weisskopf, both leading to the low-energy strength sizable to E1 one, fit experimental data best.

  20. Muscle strength and function before and after anterior cruciate ligament reconstruction using semitendonosus and gracilis.

    PubMed

    Keays, S L; Bullock-Saxton, J; Keays, A C; Newcombe, P

    2001-10-01

    This study assessed the quadriceps and hamstring strength before and 6 months after anterior cruciate ligament (ACL) reconstructive surgery using the hamstrings and related the findings to functional performance. Six months after surgery is a critical time for assessment as this is when players are returning to sport. Maximum isokinetic strength of 31 patients with complete unilateral ACL ruptures was measured at speeds of 60 degrees and 120 degrees per second. Functional assessment included the single hop, the triple hop, the shuttle run, side-step and carioca tests. All patients underwent a controlled quadriceps emphasized home-based physiotherapy program both before and after surgery. Results show that before surgery there was a 7.3% quadriceps strength deficit at 60 degrees per second compared to the uninjured leg but no hamstring strength deficit. After surgery there was a statistically significant but relatively small loss of muscle strength. The quadriceps strength deficit had increased to 12% and there was a 10% hamstring deficit. Post-operatively there was an 11% and 6.3% improvement in the hop tests, a 9% (P < 0.01) improvement in the shuttle run, a 15% (P < 0.001) improvement in the side step and a 24% (P < 0.001) improvement in the carioca tests (P < 0.001) despite the loss of muscle strength.

  1. Impact of backpack type on respiratory muscle strength and lung function in children.

    PubMed

    Vieira, Ana Christina; Ribeiro, Fernando

    2015-01-01

    We examine the influence of backpack type on lung function and respiratory muscle strength in children. Thirty-seven children were assessed for lung function and inspiratory and expiratory muscle strength under four randomly determined conditions: unloaded erect standing and three conditions carrying 15% of the child's body weight. In these three conditions, children carried the weight on a backpack with bilateral shoulder straps carried over both shoulders, on a backpack with bilateral shoulder straps carried over one shoulder and on a backpack with a mono shoulder strap. Significantly lower forced vital capacity, forced expiratory volume in one second and maximal expiratory pressure were observed when children carried a backpack with a mono shoulder strap compared to the unloaded standing position. In conclusion, the restrictive effect and the decrease in expiratory muscle strength were more pronounced for the backpack with a mono shoulder strap, suggesting that a double strap backpack is preferable to a mono shoulder strap backpack. Practitioner summary: There is little known about the effect of schoolbags on respiratory muscle function. We investigated the influence of backpack type on lung function and respiratory muscle strength. A backpack with a mono shoulder strap created a restrictive effect and a decrease in strength, suggesting that a double strap backpack is preferable to a mono shoulder strap backpack. PMID:25584722

  2. Fluctuation properties of the strength function associated with the giant quadrupole resonance in {sup 208}Pb

    SciTech Connect

    Aiba, Hirokazu; Matsuo, Masayuki; Nishizaki, Shigeru; Suzuki, Toru

    2011-02-15

    We performed fluctuation analysis by means of the local scaling dimension for the strength function of the isoscalar (IS) giant quadrupole resonance (GQR) in {sup 208}Pb where the strength function is obtained by the shell model calculation including 1p1h and 2p2h configurations. It is found that at almost all energy scales, fluctuation of the strength function obeys the Gaussian orthogonal ensemble (GOE) random matrix theory limit. This is contrasted with the results for the GQR in {sup 40}Ca, where at the intermediate energy scale of about 1.7 MeV, a deviation from the GOE limit was detected. It is found that the physical origin for this different behavior of the local scaling dimension is ascribed to the difference in the properties of the damping process.

  3. Charge-exchange modes of excitation in deformed neutron-rich nuclei

    SciTech Connect

    Yoshida, Kenichi

    2015-10-15

    Gamow-Teller (GT) mode of excitation and β-decay properties of deformed neutron-rich even-N Zr isotopes are investigated in a self-consistent Skyrme energy-density-functional approach, in which the Hartree-Fock-Bogoliubov equation is solved in the coordinate space and the proton-neutron Quasiparticle-RPA equation is solved in the quasiparticle basis. It is found that a stronger collectivity is generated for the GT giant resonance as an increase in the neutron number. Furthermore, we find that the T = 0 pairing enhances the low-lying GT strengths cooperatively with the T = 1 pairing correlation depending on the microscopic structure of the low-lying mode and the shell structure around the Fermi levels, and that the enhanced strength shortens the β-decay half-lives by at most an order of magnitude.

  4. The Radiative Strength Function Using the Neutron-Capture Reaction on 151,153Eu

    NASA Astrophysics Data System (ADS)

    Agvaanluvsan, U.; Alpizar-Vicente, A.; Becker, J. A.; Bečvář, F.; Bredeweg, T. A.; Clement, R.; Esch, E.; Folden, C. M.; Hatarik, R.; Haight, R. C.; Hoffman, D. C.; Krtička, M.; Macri, R. A.; Mitchell, G. E.; Nitsche, H.; O'Donnell, J. M.; Parker, W.; Reifarth, R.; Rundberg, R. S.; Schwantes, J. M.; Sheets, S. A.; Ullmann, J. L.; Vieira, D. J.; Wilhelmy, J. B.; Wilk, P.; Wouters, J. M.; Wu, C. Y.

    2006-03-01

    Radiative strength functions in 152,154Eu nuclei for γ-ray energies below 6 MeV have been investigated. Neutron capture for incident neutron energies <1eV up to 100 keV has been measured for 151,153Eu targets. Properties of γ decay of neutron resonances in 152,154Eu nuclei are examined. The results of measurements are compared to outcome of simulation of γ cascades based on various models for the radiative strength function. Comparison between experimental data and simulation suggests existence of the low-energy resonance in these two nuclei.

  5. The Radiative Strength Function Using the Neutron-Capture Reaction on 151,153Eu

    SciTech Connect

    Agvaanluvsan, U; Alpizar-Vicente, A; Becker, J A; Becvar, F; Bredeweg, T A; Clement, R; Esch, E; Folden, C M; Hatarik, R; Haight, R C; Hoffman, D C; Krticka, M; Macri, R A; Mitchell, G E; Nitsche, H; O'Donnell, J M; Parker, W; Reifarth, R; Rundberg, R S; Schwantes, J M; Sheets, S A; Ullmann, J L; Vieira, D J; Wilhelmy, J B; Wilk, P; Wouters, J M; Wu, C Y

    2005-10-04

    Radiative strength functions in {sup 152,154}Eu nuclei for {gamma}-ray energies below 6 MeV have been investigated. Neutron capture for incident neutron energies <1eV up to 100 keV has been measured for {sup 151,153}Eu targets. Properties of resonances in these two nuclei are examined. The measurements are compared to simulation of cascades performed with various models for the radiative strength function. Comparison between experimental data and simulation suggests an existence of the low-energy resonance in these two nuclei.

  6. Influence of Body Composition on Lung Function and Respiratory Muscle Strength in Children With Obesity

    PubMed Central

    Costa Junior, Dirceu; Peixoto-Souza, Fabiana S.; Araujo, Poliane N.; Barbalho-Moulin, Marcela C.; Alves, Viviane C.; Gomes, Evelim L. F. D.; Costa, Dirceu

    2016-01-01

    Background Obesity affects lung function and respiratory muscle strength. The aim of the present study was to assess lung function and respiratory muscle strength in children with obesity and determine the influence of body composition on these variables. Methods A cross-sectional study was conducted involving 75 children (40 with obesity and 35 within the ideal weight range) aged 6 - 10 years. Body mass index, z score, waist circumference, body composition (tetrapolar bioimpedance), respiratory muscle strength and lung function (spirometry) were evaluated. Results Children with obesity exhibited larger quantities of both lean and fat mass in comparison to those in the ideal weight range. No significant differences were found between groups regarding the respective reference values for respiratory muscle strength. Male children with obesity demonstrated significantly lower lung function values (forced expiratory volume in the first second % (FEV1%) and FEV1/forced vital capacity % (FVC%) : 93.76 ± 9.78 and 92.29 ± 3.8, respectively) in comparison to males in the ideal weight range (99.87 ± 9.72 and 96.31 ± 4.82, respectively). The regression models demonstrated that the spirometric variables were influenced by all body composition variables. Conclusion Children with obesity demonstrated a reduction in lung volume and capacity. Thus, anthropometric and body composition characteristics may be predictive factors for altered lung function. PMID:26767078

  7. Effects of supervised resistance training on fitness and functional strength in patients succeeding bariatric surgery.

    PubMed

    Huck, Corey J

    2015-03-01

    Evidence to support exercise training guidelines for patients who have undergone bariatric surgery is exceedingly limited. The purpose of this preliminary study was to evaluate the feasibility of a 12-week supervised, resistance training (RT) program and its short-term effects on physical fitness and functional strength for this population. A total of 15 patients with morbid obesity who underwent bariatric surgery participated in this quasi-experimental study. Patients were divided into 2 groups: 7 patients (age: 53.6 ± 8.2 years, body mass index [BMI]: 37.7 ± 6.3 kg·m) in an RT program and 8 patients (age: 44.0 ± 9.7 years, BMI: 32.7 ± 4.2 kg·m) following usual care; no group characteristics were significantly different at baseline. Changes in body weight, body composition, (Equation is included in full-text article.)(estimated, Ebbeling), flexibility (Sit-and-Reach Test), hand grip strength, and functional strength (sit-to-stand test [STS]) were assessed at baseline and after 12 weeks of follow-up. Adherence to RT was 84%, and no adverse events were reported. Both groups lost a significant amount of total body and fat mass; fat-free mass did not significantly change for either group. Flexibility and hand grip strength significantly improved in both groups; however, the improvements in flexibility for the RT group were significantly greater (p = 0.040). Only the RT group exhibited significant improvements in (Equation is included in full-text article.)(p = 0.025) and functional strength, STS (p = 0.002). In conclusion, supervised RT safely facilitates improvements in strength and physical functioning, increasing the patient's capacity to perform activities of daily living after bariatric surgery.

  8. Handgrip Strength, Positive Affect, and Perceived Health Are Prospectively Associated with Fewer Functional Limitations among Centenarians

    ERIC Educational Resources Information Center

    Franke, Warren D.; Margrett, Jennifer A.; Heinz, Melinda; Martin, Peter

    2012-01-01

    This study assessed the association between perceived health, fatigue, positive and negative affect, handgrip strength, objectively measured physical activity, body mass index, and self-reported functional limitations, assessed 6 months later, among 11 centenarians (age = 102 plus or minus 1). Activities of daily living, assessed 6 months prior to…

  9. Muscle Strength, Physical Activity, and Functional Limitations in Older Adults with Central Obesity

    PubMed Central

    Germain, Cassandra M.; Batsis, John A.; Vasquez, Elizabeth; McQuoid, Douglas R.

    2016-01-01

    Background. Obesity and muscle weakness are independently associated with increased risk of physical and functional impairment in older adults. It is unknown whether physical activity (PA) and muscle strength combined provide added protection against functional impairment. This study examines the association between muscle strength, PA, and functional outcomes in older adults with central obesity. Methods. Prevalence and odds of physical (PL), ADL, and IADL limitation were calculated for 6,388 community dwelling adults aged ≥ 60 with central obesity. Individuals were stratified by sex-specific hand grip tertiles and PA. Logistic models were adjusted for age, education, comorbidities, and body-mass index and weighted. Results. Overall prevalence of PL and ADL and IADL limitations were progressively lower by grip category. Within grip categories, prevalence was lower for individuals who were active than those who were inactive. Adjusted models showed significantly lower odds of PL OR 0.42 [0.31, 0.56]; ADL OR 0.60 [0.43, 0.84], and IADL OR 0.46 [0.35, 0.61] for those in the highest grip strength category as compared to those in the lowest grip category. Conclusion. Improving grip strength in obese elders who are not able to engage in traditional exercise is important for reducing odds of physical and functional impairment. PMID:27034833

  10. Relationships between Respiratory Muscle Strength and Daily Living Function in Children with Cerebral Palsy

    ERIC Educational Resources Information Center

    Wang, Hui-Yi; Chen, Chien-Chih; Hsiao, Shih-Fen

    2012-01-01

    Cerebral palsy (CP) is a common childhood disorder characterized by motor disability. Children with CP are at risk of developing significant respiratory problems associated with insufficient respiratory muscle strength. It is crucial to identify important factors which are associated with the limitations in daily living function in such children.…

  11. Thermal quasiparticle random-phase approximation with Skyrme interactions and supernova neutral-current neutrino-nucleus reactions

    NASA Astrophysics Data System (ADS)

    Dzhioev, Alan A.; Vdovin, A. I.; Martínez-Pinedo, G.; Wambach, J.; Stoyanov, Ch.

    2016-07-01

    The thermal quasiparticle random-phase approximation is combined with the Skyrme energy density functional method (Skyrme-TQRPA) to study the response of a hot nucleus to an external perturbation. For the sample nuclei 56Fe and 82Ge, the Skyrme-TQRPA is applied to analyze thermal effects on the strength function of charge-neutral Gamow-Teller transitions, which dominate neutrino-nucleus reactions at Eν≲20 MeV. For the relevant supernova temperatures we calculate the cross sections for inelastic neutrino scattering. We also apply the method to examine the rate of neutrino-antineutrino pair emission by hot nuclei. The cross sections and rates are compared with those obtained earlier from the TQRPA calculations based on the phenomenological quasiparticle-phonon model Hamiltonian. For inelastic neutrino scattering on 56Fe we also compare the Skyrme-TQRPA results to those obtained earlier from a hybrid approach that combines shell-model and RPA calculations.

  12. Microcanonical entropies and radiative strength functions of V50,51

    NASA Astrophysics Data System (ADS)

    Larsen, A. C.; Chankova, R.; Guttormsen, M.; Ingebretsen, F.; Messelt, S.; Rekstad, J.; Siem, S.; Syed, N. U. H.; Ødegård, S. W.; Lönnroth, T.; Schiller, A.; Voinov, A.

    2006-06-01

    The level densities and radiative strength functions (RSFs) of V50,51 have been extracted using the (He3,αγ) and (He3,He3'γ) reactions, respectively. From the level densities, microcanonical entropies are deduced. The high γ-energy part of the measured RSF fits well with the tail of the giant electric dipole resonance. A significant enhancement over the predicted strength in the region of Eγ≲3 MeV is seen, which at present has no theoretical explanation.

  13. Effects of Nintendo Wii Fit Plus training on ankle strength with functional ankle instability

    PubMed Central

    Kim, Ki-Jong; Jun, Hyun-Ju; Heo, Myoung

    2015-01-01

    [Purpose] The objective of this study was to examine the effects of a training program using the Nintendo Wii Fit Plus on the ankle muscle strengths of subjects with functional ankle instability. [Subjects and Methods] This study was conducted using subjects in their 20s who had functional ankle instability. They were randomized to a strengthening training group and a balance training group with 10 subjects in each, and they performed an exercise using Nintendo Wii Fit Plus for 20 minutes. In addition, every participant completed preparation and finishing exercises for 5 minutes, respectively. [Results] The muscle strengths after conducting plantar flexion and dorsiflexion significantly increased at the angular velocities of 60° and 120° in the strengthening training group. Furthermore, the muscle strengths after conducting plantar flexion, dorsiflexion, eversion, and inversion significantly increased at the angular velocities of 60° and 120° in the balance training group. [Conclusion] The balance training group using Nintendo Wii Fit Plus showed better results than the strengthening training group. Consequently, it is recommended to add the balance training program of the Nintendo Wii Fit Plus to conventional exercise programs to improve ankle muscle strength in functional ankle instability at a low cost. PMID:26696703

  14. Effects of Nintendo Wii Fit Plus training on ankle strength with functional ankle instability.

    PubMed

    Kim, Ki-Jong; Jun, Hyun-Ju; Heo, Myoung

    2015-11-01

    [Purpose] The objective of this study was to examine the effects of a training program using the Nintendo Wii Fit Plus on the ankle muscle strengths of subjects with functional ankle instability. [Subjects and Methods] This study was conducted using subjects in their 20s who had functional ankle instability. They were randomized to a strengthening training group and a balance training group with 10 subjects in each, and they performed an exercise using Nintendo Wii Fit Plus for 20 minutes. In addition, every participant completed preparation and finishing exercises for 5 minutes, respectively. [Results] The muscle strengths after conducting plantar flexion and dorsiflexion significantly increased at the angular velocities of 60° and 120° in the strengthening training group. Furthermore, the muscle strengths after conducting plantar flexion, dorsiflexion, eversion, and inversion significantly increased at the angular velocities of 60° and 120° in the balance training group. [Conclusion] The balance training group using Nintendo Wii Fit Plus showed better results than the strengthening training group. Consequently, it is recommended to add the balance training program of the Nintendo Wii Fit Plus to conventional exercise programs to improve ankle muscle strength in functional ankle instability at a low cost.

  15. Rapamycin nanoparticles target defective autophagy in muscular dystrophy to enhance both strength and cardiac function

    PubMed Central

    Bibee, Kristin P.; Cheng, Ya-Jian; Ching, James K.; Marsh, Jon N.; Li, Allison J.; Keeling, Richard M.; Connolly, Anne M.; Golumbek, Paul T.; Myerson, Jacob W.; Hu, Grace; Chen, Junjie; Shannon, William D.; Lanza, Gregory M.; Weihl, Conrad C.; Wickline, Samuel A.

    2014-01-01

    Duchenne muscular dystrophy in boys progresses rapidly to severe impairment of muscle function and death in the second or third decade of life. Current supportive therapy with corticosteroids results in a modest increase in strength as a consequence of a general reduction in inflammation, albeit with potential untoward long-term side effects and ultimate failure of the agent to maintain strength. Here, we demonstrate that alternative approaches that rescue defective autophagy in mdx mice, a model of Duchenne muscular dystrophy, with the use of rapamycin-loaded nanoparticles induce a reproducible increase in both skeletal muscle strength and cardiac contractile performance that is not achievable with conventional oral rapamycin, even in pharmacological doses. This increase in physical performance occurs in both young and adult mice, and, surprisingly, even in aged wild-type mice, which sets the stage for consideration of systemic therapies to facilitate improved cell function by autophagic disposal of toxic byproducts of cell death and regeneration.—Bibee, K. P., Cheng, Y.-J., Ching, J. K., Marsh, J. N., Li, A. J., Keeling, R. M., Connolly, A. M., Golumbek, P. T., Myerson, J. W., Hu, G., Chen, J., Shannon, W. D., Lanza, G. M., Weihl, C. C., Wickline, S. A. Rapamycin nanoparticles target defective autophagy in muscular dystrophy to enhance both strength and cardiac function. PMID:24500923

  16. Effects of Nintendo Wii Fit Plus training on ankle strength with functional ankle instability.

    PubMed

    Kim, Ki-Jong; Jun, Hyun-Ju; Heo, Myoung

    2015-11-01

    [Purpose] The objective of this study was to examine the effects of a training program using the Nintendo Wii Fit Plus on the ankle muscle strengths of subjects with functional ankle instability. [Subjects and Methods] This study was conducted using subjects in their 20s who had functional ankle instability. They were randomized to a strengthening training group and a balance training group with 10 subjects in each, and they performed an exercise using Nintendo Wii Fit Plus for 20 minutes. In addition, every participant completed preparation and finishing exercises for 5 minutes, respectively. [Results] The muscle strengths after conducting plantar flexion and dorsiflexion significantly increased at the angular velocities of 60° and 120° in the strengthening training group. Furthermore, the muscle strengths after conducting plantar flexion, dorsiflexion, eversion, and inversion significantly increased at the angular velocities of 60° and 120° in the balance training group. [Conclusion] The balance training group using Nintendo Wii Fit Plus showed better results than the strengthening training group. Consequently, it is recommended to add the balance training program of the Nintendo Wii Fit Plus to conventional exercise programs to improve ankle muscle strength in functional ankle instability at a low cost. PMID:26696703

  17. Relationships Among Lower Body Strength, Power and Performance of Functional Tasks

    NASA Technical Reports Server (NTRS)

    Ploutz-Snyder, Lori

    2010-01-01

    There is a large degree of variability among crewmembers with respect to decrements in muscle strength and power following long duration spaceflight, ranging from 0 to approx.30% reductions. The purpose of this study was to investigate the influence of varying decrements in lower body muscle strength and power (relative to body weight) on the performance of 2 occupationally relevant tasks (ladder climb and supine egress & walk). Seventeen participants with leg strength similar to US crewmembers performed a leg press power test, an isokinetic knee extension strength test and they were asked to complete the 2 functional tasks as quickly as possible. On additional test days the participants were asked to repeat the functional tasks under 3 conditions where a different external load was applied each time using a weighted suit in order to experimentally manipulate participants strength/body weight and power/body weight ratios. The weight in the suit ranged from 20-120% of body weight and was distributed in proportion to limb segment weights to minimize changes in center of gravity. The ladder task consisted of climbing 40 rungs on a ladder treadmill as fast as possible. The supine egress & walk task consisted of rising from a supine position and walking through an obstacle course. Results show a relatively linear relationship between strength/body weight and task time and power/body weight with task time such that the fastest performance times are associated with higher strength and power with about half the variance in task time is accounted for by a single variable (either strength or power). For the average person, a 20% reduction in power/body weight (from 18 to 14.4 W/kg) induces an increase (slowing) of about 10 seconds in the ladder climb task from 14 to 24 seconds (approx.70%) and a slowing of the supine egress & walk task from 14 to 21 seconds (approx.50%). Similar relationships were observed with strength/body weight and task performance. For the average

  18. Fracture strength of GaAs solar cells as a function of manufacturing process steps

    NASA Technical Reports Server (NTRS)

    Chen, C. P.; Leipold, M. H.

    1985-01-01

    Fracture of single crystal GaAs substrate during the solar cell processing is an important factor in solar cell yield and cost. Fracture mechanics technique was utilized to evaluate cell cracking characteristics and changes in fracture strength of GaAs solar cells in a present state-of-the-art of manufacturing process for GaAs solar cells from wafer to complete cell of a typical production line. Considerable change in the fracture strength of GaAs solar cells as a function of cell processing was found. The strength data were described by Weibull statistical analysis and can be interpreted with the change of flaw distribution of each of the manufacturing process steps.

  19. Total absorption spectroscopy of N = 51 nucleus 85Se

    NASA Astrophysics Data System (ADS)

    Goetz, K. C.; Grzywacz, R. K.; Rykaczewski, K. P.; Karny, M.; Fialkowska, A.; Wolinska-Cichocka, M.; Rasco, B. C.; Zganjar, E. F.; Johnson, J. W.; Gross, C. J.

    2014-09-01

    An experimental campaign utilizing the Modular Total Absorption Spectrometer (MTAS) was conducted at the HRIBF facility in January of 2012. The campaign studied 22 isotopes, many of which were identified as the highest priority for decay heat analysis during a nuclear fuel cycle, see the report by the OECD-IAEA Nuclear Energy Agency in 2007. The case of 85Se will be discussed. 85Se is a Z = 34, N = 51 nucleus with the valence neutron located in the positive parity sd single particle state. Therefore, its decay properties are determined by interplay between first forbidden decays of the valence neutron and Gamow-Teller decay of a 78Ni core. Analysis of the data obtained during the January 2012 run indicates a significant increase of the beta strength function when compared with previous measurements, see Ref..

  20. Commissioning a Tape Transport System for Decay Studies and Beam Diagnostics at CARIBU

    NASA Astrophysics Data System (ADS)

    Bertone, P. F.; Digiovine, B.; Lister, C. J.; Teh, K.; Kondev, F. G.; Nair, C.; Chowdhury, P.; Deo, A. Y.; Lakshmi, S.

    2011-10-01

    The CAlifornium Rare Isotope Breeder Upgrade (CARIBU) to the ATLAS facility at Argonne utilizes the spontaneous fission of 252 Cf for producing neutron-rich radioactive nuclei. CARIBU will be used for a wide variety of experiments, involving both reaccelerated and stopped beams, in nuclear structure, nuclear astrophysics and applications. Many of these experiments will require a means of transporting radioactivity to and from detector counting stations for the purpose of assaying beam content, measuring half-lives, β- γ spectroscopy and determining Gamow-Teller strength distributions. We have commissioned the first of several tape transport systems that will perform these functions. An overview of the design and deployment of the system will be given along with preliminary test results. Supported by the U.S. DOE Office of Nuclear Physics DE-AC02-06CH11357.

  1. Photon strength functions in Gd isotopes studied from radiative capture of resonance neutrons

    NASA Astrophysics Data System (ADS)

    Kroll, J.; Baramsai, B.; Mitchell, G. E.; Agvaanluvsan, U.; Bečvář, F.; Bredeweg, T. A.; Chyzh, A.; Couture, A.; Dashdorj, D.; Haight, R. C.; Jandel, M.; Keksis, A. L.; Krtička, M.; O'Donnell, J. M.; Parker, W.; Rundberg, R. S.; Ullmann, J. L.; Valenta, S.; Vieira, D. J.; Walker, C.; Wu, C. Y.

    2014-04-01

    The experimental spectra of γ rays following radiative neutron capture on isolated resonances of stable 152,154-158Gd targets were measured by the DANCE calorimeter installed at the Los Alamos Neutron Scattering Center in New Mexico, USA. These spectra were analyzed within the extreme statistical model to get new information on the photon strength functions. Special emphasis was put on study of the scissors vibrational mode present in these isotopes. Our data show that the scissors-mode resonances are built not only on the ground states but also on the excited levels of all studied Gd isotopes. The scissors mode strength observed in 157,159Gd products is significantly higher than in neighboring even-even nuclei 156,158Gd. Such a difference indicates the existence of an odd-even effect in the scissors mode strength. Moreover, there exists no universal parameter-free model of the electric dipole photon strength function describing the experimental data in all of the Gd isotopes studied. The results for the scissors mode are compared with the (γ, γ') data for the ground-state transitions and with the results from 3He-induced reactions.

  2. Predicting the biomechanical strength of proximal femur specimens with Minkowski functionals and support vector regression

    NASA Astrophysics Data System (ADS)

    Yang, Chien-Chun; Nagarajan, Mahesh B.; Huber, Markus B.; Carballido-Gamio, Julio; Bauer, Jan S.; Baum, Thomas; Eckstein, Felix; Lochmüller, Eva-Maria; Link, Thomas M.; Wismüller, Axel

    2014-03-01

    Regional trabecular bone quality estimation for purposes of femoral bone strength prediction is important for improving the clinical assessment of osteoporotic fracture risk. In this study, we explore the ability of 3D Minkowski Functionals derived from multi-detector computed tomography (MDCT) images of proximal femur specimens in predicting their corresponding biomechanical strength. MDCT scans were acquired for 50 proximal femur specimens harvested from human cadavers. An automated volume of interest (VOI)-fitting algorithm was used to define a consistent volume in the femoral head of each specimen. In these VOIs, the trabecular bone micro-architecture was characterized by statistical moments of its BMD distribution and by topological features derived from Minkowski Functionals. A linear multiregression analysis and a support vector regression (SVR) algorithm with a linear kernel were used to predict the failure load (FL) from the feature sets; the predicted FL was compared to the true FL determined through biomechanical testing. The prediction performance was measured by the root mean square error (RMSE) for each feature set. The best prediction result was obtained from the Minkowski Functional surface used in combination with SVR, which had the lowest prediction error (RMSE = 0.939 ± 0.345) and which was significantly lower than mean BMD (RMSE = 1.075 ± 0.279, p<0.005). Our results indicate that the biomechanical strength prediction can be significantly improved in proximal femur specimens with Minkowski Functionals extracted from on MDCT images used in conjunction with support vector regression.

  3. Muscle activity during functional coordination training: implications for strength gain and rehabilitation.

    PubMed

    Jørgensen, Marie B; Andersen, Lars L; Kirk, Niels; Pedersen, Mogens T; Søgaard, Karen; Holtermann, Andreas

    2010-07-01

    The purpose of this study was to evaluate if different types, body positions, and levels of progression of functional coordination exercises can provide sufficiently high levels of muscle activity to improve strength of the neck, shoulder, and trunk muscles. Nine untrained women were familiarized with 7 functional coordination exercises 12 times during 4 weeks before testing. Surface electromyographic (EMG) activity was obtained from rectus abdominus, erector spinae, obliquus externus, and trapezius during the exercises with 2-4 levels of progression. Electromyography was normalized to the maximal EMG activity during maximal voluntary contractions, and a p value < 0.05 was considered significant. All recorded muscles reached sufficiently high levels of activity during the coordination exercises for strength gain (>60% of maximal EMG activity). Type of exercise played a significant role for the attained muscle activity. Body position during the exercises was important for the activity of the erector spinae, and level of progression was important for the activity of the trapezius. The findings indicate that depending on type, body position, and level of progression, functional coordination training can be performed with a muscle activity sufficient for strength gain. Functional coordination training may therefore be a good choice for prevention or rehabilitation of musculoskeletal pain or injury in the neck, shoulder, or trunk muscles.

  4. Lower limb strength training in children with cerebral palsy – a randomized controlled trial protocol for functional strength training based on progressive resistance exercise principles

    PubMed Central

    Scholtes, Vanessa A; Dallmeijer, Annet J; Rameckers, Eugene A; Verschuren, Olaf; Tempelaars, Els; Hensen, Maartje; Becher, Jules G

    2008-01-01

    Background Until recently, strength training in children with cerebral palsy (CP) was considered to be inappropriate, because it could lead to increased spasticity or abnormal movement patterns. However, the results of recent studies suggest that progressive strength training can lead to increased strength and improved function, but low methodological quality and incomplete reporting on the training protocols hampers adequate interpretation of the results. This paper describes the design and training protocol of a randomized controlled trial to assess the effects of a school-based progressive functional strength training program for children with CP. Methods/Results Fifty-one children with Gross Motor Function Classification Systems levels I to III, aged of 6 to 13 years, were recruited. Using stratified randomization, each child was assigned to an intervention group (strength training) or a control group (usual care). The strength training was given in groups of 4–5 children, 3 times a week, for a period of 12 weeks. Each training session focussed on four exercises out of a 5-exercise circuit. The training load was gradually increased based on the child's maximum level of strength, as determined by the 8 Repetition Maximum (8 RM). To evaluate the effectiveness of the training, all children were evaluated before, during, directly after, and 6 weeks after the intervention period. Primary outcomes in this study were gross motor function (measured with the Gross Motor Function Measure and functional muscle strength tests) and walking ability (measured with the 10-meter, the 1-minute and the timed stair test). Secondary outcomes were lower limb muscle strength (measured with a 6 RM test, isometric strength tests, and a sprint capacity test), mobility (measured with a mobility questionnaire), and sport activities (measured with the Children's Assessment of Participation and Enjoyment). Spasticity and range of motion were assessed to evaluate any adverse events

  5. New method to study the photon strength function using the beta-decay of unstable nuclei

    NASA Astrophysics Data System (ADS)

    Liddick, Sean

    2015-10-01

    The photon strength function is a fundamental property of the atomic nucleus that can be linked with many different areas of nuclear science. In particular, a knowledge of the photon strength function can be applied in statistical-model reaction calculations to constrain neutron capture rates useful for nuclear astrophysics and other applications. A new method has been developed which takes advantage of beta-decay to populate high-energy states in a daughter nucleus. This preparation is combined with a total absorption spectrometer to record the subsequent gamma-ray cascade and the overall technique is the so-called beta-Oslo method. The technique is applicable to very low production rates (~1 pps) and, thus, can be used to look at trends across a wide range of neutron and proton numbers. A description of the technique, and preliminary results on neutron-rich nuclei near Z = 28 and N = 40 will be presented.

  6. Prehabilitation before total knee arthroplasty increases strength and function in older adults with severe osteoarthritis.

    PubMed

    Swank, Ann M; Kachelman, Joseph B; Bibeau, Wendy; Quesada, Peter M; Nyland, John; Malkani, Arthur; Topp, Robert V

    2011-02-01

    Preparing for the stress of total knee arthroplasty (TKA) surgery by exercise training (prehabilitation) may improve strength and function before surgery and, if effective, has the potential to contribute to postoperative recovery. Subjects with severe osteoarthritis (OA), pain intractable to medicine and scheduled for TKA were randomized into a usual care (UC) group (n = 36) or usual care and exercise (UC + EX) group (n = 35). The UC group maintained normal daily activities before their TKA. The UC + EX group performed a comprehensive prehabilitation program that included resistance training using bands, flexibility, and step training at least 3 times per week for 4-8 weeks before their TKA in addition to UC. Leg strength (isokinetic peak torque for knee extension and flexion) and ability to perform functional tasks (6-minute walk, 30 second sit-to-stand repetitions, and the time to ascend and descend 2 flights of stairs) were assessed before randomization at baseline (T1) and 1 week before the subject's TKA (T2). Repeated-measures analysis of variance indicated a significant group by time interaction (p < 0.05) for the 30-second sit-to-stand repetitions, time to ascend the first flight of stairs, and peak torque for knee extension in the surgical knee. Prehabilitation increased leg strength and the ability to perform functional tasks for UC + EX when compared to UC before TKA. Short term (4-8 weeks) of prehabilitation was effective for increasing strength and function for individuals with severe OA. The program studied is easily transferred to a home environment, and clinicians working with this population should consider prehabilitation before TKA.

  7. Level densities and gamma-ray strength functions in 170,171,172-Yb

    SciTech Connect

    Agvaanluvsan, U; Schiller, A; Becker, J; Bernstein, L; Garrett, P; Guttormsen, M; Mitchell, G; Rekstad, J; Siem, S; Voinov, A; Younes, W

    2004-07-28

    Level densities and radiative strength functions in {sup 171}Yb and {sup 170}Yb nuclei have been measured using the {sup 171}Yb({sup 3}He{sup 3}He{gamma}){sup 171}Yb and {sup 171}Yb({sup 3}He,{alpha}{gamma}){sup 170}Yb reactions. New data on {sup 171}Yb are compared to a previous measurement for {sup 171}Yb from the {sup 172}Yb({sup 3}He,{alpha}{gamma}){sup 171}Yb reaction. Systematics of level densities and radiative strength functions in {sup 170,171,172}Yb are established. The entropy excess in {sup 171}Yb relative to the even-even nuclei {sup 170,172}Yb due to the unpaired neutron quasiparticle is found to be approximately 2k{sub B}. Results for the radiative strength function from the two reactions lead to consistent parameters characterizing the ''pygmy'' resonances. Pygmy resonances in the {sup 170,172}Yb populated by the ({sup 3}He,{alpha}) reaction appear to be split into two components for both of which a complete set of resonance parameters are obtained.

  8. Effect of caffeine on respiratory muscle strength and lung function in prematurely born, ventilated infants.

    PubMed

    Kassim, Zainab; Greenough, Anne; Rafferty, Gerrard F

    2009-12-01

    The aims of this study were to determine whether caffeine administration increased respiratory muscle function and if this was associated with lung function improvement in prematurely born infants being weaned from mechanical ventilation. Respiratory muscle function was assessed by measurement of the maximum pressures generated during occlusions at end inspiration (Pemax) and end expiration (Pimax) and lung function by measurement of lung volume (functional residual capacity (FRC)) and respiratory system compliance (CRS) and resistance (RRS) in 18 infants with a median gestational age of 28 (range 24-36) weeks. Measurements were made immediately prior to caffeine administration (baseline) and 6 h later. Six hours after caffeine administration compared to baseline, the median Pemax (p = 0.017), Pimax (p = 0.004), FRC (p < 0.001), CRS (p = 0.002) and RRS (p = 0.004) had significantly improved. Our results suggest that caffeine administration facilitates weaning of prematurely born infants from mechanical ventilation by improving respiratory muscle strength.

  9. Size dependence of yield strength simulated by a dislocation-density function dynamics approach

    NASA Astrophysics Data System (ADS)

    Leung, P. S. S.; Leung, H. S.; Cheng, B.; Ngan, A. H. W.

    2015-04-01

    The size dependence of the strength of nano- and micron-sized crystals is studied using a new simulation approach in which the dynamics of the density functions of dislocations are modeled. Since any quantity of dislocations can be represented by a density, this approach can handle large systems containing large quantities of dislocations, which may handicap discrete dislocation dynamics schemes due to the excessive computation time involved. For this reason, pillar sizes spanning a large range, from the sub-micron to micron regimes, can be simulated. The simulation results reveal the power-law relationship between strength and specimen size up to a certain size, beyond which the strength varies much more slowly with size. For specimens smaller than ∼4000b, their strength is found to be controlled by the dislocation depletion condition, in which the total dislocation density remains almost constant throughout the loading process. In specimens larger than ∼4000b, the initial dislocation distribution is of critical importance since the presence of dislocation entanglements is found to obstruct deformation in the neighboring regions within a distance of ∼2000b. This length scale suggests that the effects of dense dislocation clusters are greater in intermediate-sized specimens (e.g. 4000b and 8000b) than in larger specimens (e.g. 16 000b), according to the weakest-link concept.

  10. Evaluation of Suited and Unsuited Human Functional Strength Using Multipurpose, Multiaxial Isokinetic Dynamometer

    NASA Technical Reports Server (NTRS)

    Aghazadeh, Fred

    2005-01-01

    The objective of the planned summer research was to develop a procedure to determine the isokinetic functional strength of suited and unsuited participants in order to estimate the coefficient of micro-gravity suit on human strength. To accomplish this objective, the Anthropometry and Biomechanics Facility's Multipurpose, Multiaxial Isokinetic dynamometer (MMID) was used. Development of procedure involved selection and testing of seven routines to be tested on MMID. We conducted the related experiments and collected the data for 12 participants. In addition to the above objective, we developed a procedure to assess the fatiguing characteristics of suited and unsuited participants using EMG technique. We collected EMG data on 10 participants while performing a programmed routing on MMID. EMG data along with information on the exerted forces, effector speed, number of repetitions, and duration of each routine were recorded for further analysis. Finally, gathering and tabulation Of data for various human strengths for updating of MSIS (HSIS) strength requirement, which started in summer 2003, also continued.

  11. Gonadal Steroids and Body Composition, Strength, and Sexual Function in Men

    PubMed Central

    Finkelstein, Joel S.; Lee, Hang; Burnett-Bowie, Sherri-Ann M.; Pallais, J. Carl; Yu, Elaine W.; Borges, Lawrence F.; Jones, Brent F.; Barry, Christopher V.; Wulczyn, Kendra E.; Thomas, Bijoy J.; Leder, Benjamin Z.

    2014-01-01

    BACKGROUND Current approaches to diagnosing testosterone deficiency do not consider the physiological consequences of various testosterone levels or whether deficiencies of testosterone, estradiol, or both account for clinical manifestations. METHODS We provided 198 healthy men 20 to 50 years of age with goserelin acetate (to suppress endogenous testosterone and estradiol) and randomly assigned them to receive a placebo gel or 1.25 g, 2.5 g, 5 g, or 10 g of testosterone gel daily for 16 weeks. Another 202 healthy men received goserelin acetate, placebo gel or testosterone gel, and anastrozole (to suppress the conversion of testosterone to estradiol). Changes in the percentage of body fat and in lean mass were the primary outcomes. Subcutaneous- and intraabdominal-fat areas, thigh-muscle area and strength, and sexual function were also assessed. RESULTS The percentage of body fat increased in groups receiving placebo or 1.25 g or 2.5 g of testosterone daily without anastrozole (mean testosterone level, 44±13 ng per deciliter, 191±78 ng per deciliter, and 337±173 ng per deciliter, respectively). Lean mass and thigh-muscle area decreased in men receiving placebo and in those receiving 1.25 g of testosterone daily without anastrozole. Leg-press strength fell only with placebo administration. In general, sexual desire declined as the testosterone dose was reduced. CONCLUSIONS The amount of testosterone required to maintain lean mass, fat mass, strength, and sexual function varied widely in men. Androgen deficiency accounted for decreases in lean mass, muscle size, and strength; estrogen deficiency primarily accounted for increases in body fat; and both contributed to the decline in sexual function. Our findings support changes in the approach to evaluation and management of hypogonadism in men. PMID:24024838

  12. Measures of Functional Performance and Their Association With Hip and Thigh Strength

    PubMed Central

    Kollock, Roger; Van Lunen, Bonnie L.; Ringleb, Stacie I.; Oñate, James A.

    2015-01-01

    Context: Insufficient hip and thigh strength may increase an athlete's susceptibility to injury. However, screening for strength deficits using isometric and isokinetic instrumentation may not be practical in all clinical scenarios. Objective: To determine if functional performance tests are valid indicators of hip and thigh strength. Design: Descriptive laboratory study. Setting: Research laboratory. Patients or Other Participants: Sixty-two recreationally athletic men (n = 30, age = 21.07 years, height = 173.84 cm, mass = 81.47 kg) and women (n = 32, age = 21.03 years, height = 168.77 cm, mass = 68.22 kg) participants were recruited. Intervention(s): During session 1, we measured isometric peak force and rate of force development for 8 lower extremity muscle groups, followed by an isometric endurance test. During session 2, participants performed functional performance tests. Main Outcome Measure(s): Peak force, rate of force development, fatigue index, hop distance (or height), work (joules), and number of hops performed during the 30-second lateral-hop test were assessed. The r values were squared to calculate r 2. We used Pearson correlations to evaluate the associations between functional performance and strength. Results: In men, the strongest relationship was observed between triple-hop work and hip-adductor peak force (r2 = 50, P ≤ .001). Triple-hop work also was related to hip-adductor (r2 = 38, P ≤ .01) and hip-flexor (r2 = 37, P ≤ .01) rate of force development. For women, the strongest relationships were between single-legged vertical-jump work and knee-flexor peak force (r2 = 0.44, P ≤ .01) and single-legged vertical-jump height and knee-flexor peak force (r2 = 0.42, P ≤ .01). Single-legged vertical-jump height also was related to knee-flexor rate of force development (r2 = 0.49, P ≤ .001). The 30-second lateral-hop test did not account for a significant portion of the variance in strength endurance. Conclusions: Hop tests alone did not

  13. Gamma-Ray Strength Function Method:. Away from Photoneutron Emission to Radiative Neutron Capture

    NASA Astrophysics Data System (ADS)

    Utsunomiya, H.; Akimune, H.; Yamagata, T.; Iwamoto, C.; Goriely, S.; Daoutidis, I.; Toyokawa, H.; Harada, H.; Kitatani, F.; Iwamoto, N.; Lui, Y. W.; Arteaga, D. P.; Hilaire, S.; Koning, A. J.

    2013-03-01

    Radiative neutron capture cross sections are of direct relevance for the synthesis of heavy elements referred to as the s-process and the r-process in nuclear astrophysics and constitute basic data in the field of nuclear engineering. The surrogate reaction technique is in active use to indirectly determine radiative neutron capture cross sections for unstable nuclei. We have devised an indirect method alternative to the surrogate reaction technique on the basis of the γ-ray strength function (γSF), a nuclear statistical quantity that interconnects photoneutron emission and radiative neutron capture in the Hauser-Feshbach model calculation. We outline the γSF method and show applications of the method to tin, palladium, and zirconium isotopes. In the application of the γSF method, it is important to use γSF's that incorporate extra strengths of PDR and/or M1 resonance emerging around neutron threshold.

  14. Radial basis function network learns ceramic processing and predicts related strength and density

    NASA Technical Reports Server (NTRS)

    Cios, Krzysztof J.; Baaklini, George Y.; Vary, Alex; Tjia, Robert E.

    1993-01-01

    Radial basis function (RBF) neural networks were trained using the data from 273 Si3N4 modulus of rupture (MOR) bars which were tested at room temperature and 135 MOR bars which were tested at 1370 C. Milling time, sintering time, and sintering gas pressure were the processing parameters used as the input features. Flexural strength and density were the outputs by which the RBF networks were assessed. The 'nodes-at-data-points' method was used to set the hidden layer centers and output layer training used the gradient descent method. The RBF network predicted strength with an average error of less than 12 percent and density with an average error of less than 2 percent. Further, the RBF network demonstrated a potential for optimizing and accelerating the development and processing of ceramic materials.

  15. Efficiency of muscle strength training on motor function in patients with coronary artery disease: a meta-analysis

    PubMed Central

    Yang, Yu-Jie; He, Xiao-Hua; Guo, Hai-Ying; Wang, Xue-Qiang; Zhu, Yi

    2015-01-01

    Background: Existing literature has shown that patients with coronary artery disease (CAD) can benefit greatly from the strength training; therefore, the strength training should play a more important role in cardiac rehabilitation. However, the medical community may still have conservation to apply the strength training owing to no comprehensive study so far to compare the effectiveness of the strength training to the other trainings, such as aerobic training. Objective: To evaluate the effect of strength training on motor function in patients with CAD. Methods: Published articles from the earliest date available to July 2015 were identified using electronic searches. Two reviewers selected independently relevant randomized controlled trials (RCTs) investigating exercise program with strength training versus control interventions (exercise without strength training, including aerobic training and no exercise group) for the treatment of CAD patients. We examined effects of exercise with strength training versus control interventions on peak oxygen uptake (VO2peak), duration of exercise test and muscle strength. Two reviewers extracted data independently. Results: Twenty seven trials that represented 1151 participants passed the selection criteria and were evaluated for the effects of strength training in CAD patients. For improving VO2peak [SMD (95%CI) = 0.58 (0.11, 1.06)] and muscle strength [upper limb, SMD (95% CI) =0.44 (0.34, 0.55); lower limb, SMD (95% CI) =0.33 (0.16, 0.50)], exercise program with strength training were significantly more effective than one without it. But there is no significantly difference on duration of exercise test [SMD (95%CI) = 0.17 (-0.04, 0.39)] in strength training group than in control group. Conclusions: We conclude strength training is effective in improving muscle strength and VO2peak, in CAD patients, when compared to patients with control group. Furthermore, our evaluations suggest that strength training does not compromise

  16. Adverse effect of femoral nerve blockade on quadriceps strength and function after ACL reconstruction.

    PubMed

    Krych, Aaron; Arutyunyan, Grigoriy; Kuzma, Scott; Levy, Bruce; Dahm, Diane; Stuart, Michael

    2015-02-01

    The purpose of this study was to determine if quadriceps strength and functional outcomes were similar at 6 months following anterior cruciate ligament [ACL] reconstruction in patients receiving a continuous 48-hour femoral nerve blockade for postoperative analgesia (FNB group) versus patients with no FNB (control group). A retrospective cohort was designed including athletes who underwent primary ACL reconstruction with patellar tendon autograft between 2005 and 2010 at our institution with identical rehabilitation protocols. The FNB group included 96 patients with an average age of 21 years and the control group included 100 patients with an average age of 20 years. At 6 months following ACL reconstruction, isokinetic strength (slow and fast activation) and functional tests including vertical jump, single hop, triple hop, and return to sport were analyzed with an α value < 0.05 as significant. Multivariate regression models were used to compare these outcomes between the FNB and control groups after adjusting for gender and competitive athlete status. At 6 months, fast extension isokinetic strength was inferior in the FNB group (78 vs. 85%; p < 0.01). After adjusting for gender and competitive athlete status, fast (p = 0.002) and slow extension strength (p = 0.01), vertical jump (p = 0.03) and single jump (p = 0.02) were also inferior in the FNB group. There were no significant differences in full return to sport between the two groups (86% at 7.5 months in the FNB group vs. 93% at 7.3 months in the control group). In this retrospective comparative study, the hypothesis that patients treated with continuous FNB for postoperative analgesia following ACL reconstruction with patellar tendon autograft will have inferior knee extension (quadriceps) strength and function at 6 months follow-up was affirmed. However, no differences were observed in return to sport, bringing into question whether these statistical differences translate into

  17. Immediate effect of manual therapy on respiratory functions and inspiratory muscle strength in patients with COPD

    PubMed Central

    Yilmaz Yelvar, Gul Deniz; Çirak, Yasemin; Demir, Yasemin Parlak; Dalkilinç, Murat; Bozkurt, Bülent

    2016-01-01

    Objective The objective of this study was to investigate the immediate effect of manual therapy (MT) on respiratory functions and inspiratory muscle strength in patients with COPD. Participants and methods Thirty patients with severe COPD (eight females and 22 males; mean age 62.4±6.8 years) referred to pulmonary physiotherapy were included in this study. The patients participated in a single session of MT to measure the short-term effects. The lung function was measured using a portable spirometer. An electronic pressure transducer was used to measure respiratory muscle strength. Heart rate, breathing frequency, and oxygen saturation were measured with a pulse oximeter. For fatigue and dyspnea perception, the modified Borg rating of perceived exertion scale was used. All measurements were taken before and immediately after the first MT session. The ease-of-breathing visual analog scale was used for rating patients’ symptoms subjectively during the MT session. Results There was a significant improvement in the forced expiratory volume in the first second, forced vital capacity, and vital capacity values (P<0.05). The maximal inspiratory pressure and maximal expiratory pressure values increased significantly after MT, compared to the pre-MT session (P<0.05). There was a significant decrease in heart rate, respiratory rate (P<0.05), and dyspnea and fatigue perception (P<0.05). Conclusion A single MT session immediately improved pulmonary function, inspiratory muscle strength, and oxygen saturation and reduced dyspnea, fatigue, and heart and respiratory rates in patients with severe COPD. MT should be added to pulmonary rehabilitation treatment as a new alternative that is fast acting and motivating in patients with COPD. PMID:27382271

  18. A comparison of the strength of biodiversity effects across multiple functions.

    PubMed

    Allan, Eric; Weisser, Wolfgang W; Fischer, Markus; Schulze, Ernst-Detlef; Weigelt, Alexandra; Roscher, Christiane; Baade, Jussi; Barnard, Romain L; Beßler, Holger; Buchmann, Nina; Ebeling, Anne; Eisenhauer, Nico; Engels, Christof; Fergus, Alexander J F; Gleixner, Gerd; Gubsch, Marlén; Halle, Stefan; Klein, Alexandra M; Kertscher, Ilona; Kuu, Annely; Lange, Markus; Le Roux, Xavier; Meyer, Sebastian T; Migunova, Varvara D; Milcu, Alexandru; Niklaus, Pascal A; Oelmann, Yvonne; Pašalić, Esther; Petermann, Jana S; Poly, Franck; Rottstock, Tanja; Sabais, Alexander C W; Scherber, Christoph; Scherer-Lorenzen, Michael; Scheu, Stefan; Steinbeiss, Sibylle; Schwichtenberg, Guido; Temperton, Vicky; Tscharntke, Teja; Voigt, Winfried; Wilcke, Wolfgang; Wirth, Christian; Schmid, Bernhard

    2013-09-01

    In order to predict which ecosystem functions are most at risk from biodiversity loss, meta-analyses have generalised results from biodiversity experiments over different sites and ecosystem types. In contrast, comparing the strength of biodiversity effects across a large number of ecosystem processes measured in a single experiment permits more direct comparisons. Here, we present an analysis of 418 separate measures of 38 ecosystem processes. Overall, 45 % of processes were significantly affected by plant species richness, suggesting that, while diversity affects a large number of processes not all respond to biodiversity. We therefore compared the strength of plant diversity effects between different categories of ecosystem processes, grouping processes according to the year of measurement, their biogeochemical cycle, trophic level and compartment (above- or belowground) and according to whether they were measures of biodiversity or other ecosystem processes, biotic or abiotic and static or dynamic. Overall, and for several individual processes, we found that biodiversity effects became stronger over time. Measures of the carbon cycle were also affected more strongly by plant species richness than were the measures associated with the nitrogen cycle. Further, we found greater plant species richness effects on measures of biodiversity than on other processes. The differential effects of plant diversity on the various types of ecosystem processes indicate that future research and political effort should shift from a general debate about whether biodiversity loss impairs ecosystem functions to focussing on the specific functions of interest and ways to preserve them individually or in combination.

  19. Effect of neuromuscular electrical stimulation on facial muscle strength and oral function in stroke patients with facial palsy

    PubMed Central

    Choi, Jong-Bae

    2016-01-01

    [Purpose] The aim of this study was to investigate the effect of neuromuscular electrical stimulation on facial muscle strength and oral function in stroke patients with facial palsy. [Subjects and Methods] Nine subjects received the electrical stimulation and traditional dysphagia therapy. Electrical stimulation was applied to stimulate each subject’s facial muscles 30 minutes a day, 5 days a week, for 4 weeks. [Results] Subjects showed significant improvement in cheek and lip strength and oral function after the intervention. [Conclusion] This study demonstrates that electrical stimulation improves facial muscle strength and oral function in stroke patients with dysphagia. PMID:27799689

  20. Training-specific functional, neural, and hypertrophic adaptations to explosive- vs. sustained-contraction strength training.

    PubMed

    Balshaw, Thomas G; Massey, Garry J; Maden-Wilkinson, Thomas M; Tillin, Neale A; Folland, Jonathan P

    2016-06-01

    Training specificity is considered important for strength training, although the functional and underpinning physiological adaptations to different types of training, including brief explosive contractions, are poorly understood. This study compared the effects of 12 wk of explosive-contraction (ECT, n = 13) vs. sustained-contraction (SCT, n = 16) strength training vs. control (n = 14) on the functional, neural, hypertrophic, and intrinsic contractile characteristics of healthy young men. Training involved 40 isometric knee extension repetitions (3 times/wk): contracting as fast and hard as possible for ∼1 s (ECT) or gradually increasing to 75% of maximum voluntary torque (MVT) before holding for 3 s (SCT). Torque and electromyography during maximum and explosive contractions, torque during evoked octet contractions, and total quadriceps muscle volume (QUADSVOL) were quantified pre and post training. MVT increased more after SCT than ECT [23 vs. 17%; effect size (ES) = 0.69], with similar increases in neural drive, but greater QUADSVOL changes after SCT (8.1 vs. 2.6%; ES = 0.74). ECT improved explosive torque at all time points (17-34%; 0.54 ≤ ES ≤ 0.76) because of increased neural drive (17-28%), whereas only late-phase explosive torque (150 ms, 12%; ES = 1.48) and corresponding neural drive (18%) increased after SCT. Changes in evoked torque indicated slowing of the contractile properties of the muscle-tendon unit after both training interventions. These results showed training-specific functional changes that appeared to be due to distinct neural and hypertrophic adaptations. ECT produced a wider range of functional adaptations than SCT, and given the lesser demands of ECT, this type of training provides a highly efficient means of increasing function.

  1. Progressive resistance strength training for improving physical function in older adults

    PubMed Central

    Liu, Chiung-ju; Latham, Nancy K

    2014-01-01

    Background Muscle weakness in old age is associated with physical function decline. Progressive resistance strength training (PRT) exercises are designed to increase strength. Objectives To assess the effects of PRT on older people and identify adverse events. Search methods We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialized Register (to March 2007), the Cochrane Central Register of Controlled Trials (The Cochrane Library 2007, Issue 2), MEDLINE (1966 to May 01, 2008), EMBASE (1980 to February 06 2007), CINAHL (1982 to July 01 2007) and two other electronic databases. We also searched reference lists of articles, reviewed conference abstracts and contacted authors. Selection criteria Randomised controlled trials reporting physical outcomes of PRT for older people were included. Data collection and analysis Two review authors independently selected trials, assessed trial quality and extracted data. Data were pooled where appropriate. Main results One hundred and twenty one trials with 6700 participants were included. In most trials, PRT was performed two to three times per week and at a high intensity. PRT resulted in a small but significant improvement in physical ability (33 trials, 2172 participants; SMD 0.14, 95% CI 0.05 to 0.22). Functional limitation measures also showed improvements: e.g. there was a modest improvement in gait speed (24 trials, 1179 participants, MD 0.08 m/s, 95% CI 0.04 to 0.12); and a moderate to large effect for getting out of a chair (11 trials, 384 participants, SMD -0.94, 95% CI -1.49 to -0.38). PRT had a large positive effect on muscle strength (73 trials, 3059 participants, SMD 0.84, 95% CI 0.67 to 1.00). Participants with osteoarthritis reported a reduction in pain following PRT (6 trials, 503 participants, SMD -0.30, 95% CI -0.48 to -0.13). There was no evidence from 10 other trials (587 participants) that PRT had an effect on bodily pain. Adverse events were poorly recorded but adverse events related to

  2. Functional mobility and balance in community-dwelling elderly submitted to multisensory versus strength exercises

    PubMed Central

    Alfieri, Fábio Marcon; Riberto, Marcelo; Gatz, Lucila Silveira; Ribeiro, Carla Paschoal Corsi; Lopes, José Augusto Fernandes; Santarém, José Maria; Battistella, Linamara Rizzo

    2010-01-01

    It is well documented that aging impairs balance and functional mobility. The objective of this study was to compare the efficacy of multisensory versus strength exercises on these parameters. We performed a simple blinded randomized controlled trial with 46 community-dwelling elderly allocated to strength ([GST], N = 23, 70.2-years-old ± 4.8 years) or multisensory ([GMS], N = 23, 68.8-years-old ± 5.9 years) exercises twice a week for 12 weeks. Subjects were evaluated by blinded raters using the timed ‘up and go’ test (TUG), the Guralnik test battery, and a force platform. By the end of the treatment, the GMS group showed a significant improvement in TUG (9.1 ± 1.9 seconds (s) to 8.0 ± 1.0 s, P = 0.002); Guralnik test battery (10.6 ± 1.2 to 11.3 ± 0.8 P = 0.009); lateromedial (6.1 ± 11.7 cm to 3.1 ± 1.6 cm, P = 0.02) and anteroposterior displacement (4.7 ± 4.2 cm to 3.4 ± 1.0 cm, P = 0.03), which were not observed in the GST group. These results reproduce previous findings in the literature and mean that the stimulus to sensibility results in better achievements for the control of balance and dynamic activities. Multisensory exercises were shown to be more efficacious than strength exercises to improve functional mobility. PMID:20711437

  3. Assessment of neuromuscular function after different strength training protocols using tensiomyography.

    PubMed

    de Paula Simola, Rauno Á; Harms, Nico; Raeder, Christian; Kellmann, Michael; Meyer, Tim; Pfeiffer, Mark; Ferrauti, Alexander

    2015-05-01

    The purpose of the study was to analyze tensiomyography (TMG) sensitivity to changes in muscle force and neuromuscular function of the muscle rectus femoris (RF) using TMG muscle properties after 5 different lower-limb strength training protocols (multiple sets; DS = drop sets; eccentric overload; FW = flywheel; PL = plyometrics). After baseline measurements, 14 male strength trained athletes completed 1 squat training protocol per week over a 5-week period in a randomized controlled order. Maximal voluntary isometric contraction (MVIC), TMG measurements of maximal radial displacement of the muscle belly (Dm), contraction time between 10 and 90% of Dm (Tc), and mean muscle contraction velocities from the beginning until 10% (V10) and 90% of Dm (V90) were analyzed up to 0.5 (post-train), 24 (post-24), and 48 hours (post-48) after the training interventions. Significant analysis of variance main effects for measurement points were found for all TMG contractile properties and MVIC (p < 0.01). Dm and V10 post-train values were significantly lower after protocols DS and FW compared with protocol PL (p = 0.032 and 0.012, respectively). Dm, V10, and V90 decrements correlated significantly to the decreases in MVIC (r = 0.64-0.67, p ≤ 0.05). Some TMG muscle properties are sensitive to changes in muscle force, and different lower-limb strength training protocols lead to changes in neuromuscular function of RF. In addition, those protocols involving high and eccentric load and a high total time under tension may induce higher changes in TMG muscle properties. PMID:25474337

  4. Balance Exercises Circuit improves muscle strength, balance, and functional performance in older women.

    PubMed

    Avelar, Bruna Pereira; Costa, Juliana Nunes de Almeida; Safons, Marisete Peralta; Dutra, Maurílio Tiradentes; Bottaro, Martim; Gobbi, Sebastião; Tiedemann, Anne; de David, Ana Cristina; Lima, Ricardo Moreno

    2016-02-01

    This study introduces the Balance Exercises Circuit (BEC) and examines its effects on muscle strength and power, balance, and functional performance in older women. Thirty-five women aged 60+ (mean age = 69.31, SD = 7.35) were assigned to either a balance exercises group (BG, n = 14) that underwent 50-min sessions twice weekly, of a 12-week BEC program, or a wait-list control group (CG, n = 21). Outcome measures were knee extensor peak torque (PT), rate of force development (RFD), balance, Timed Up & Go (TUG), 30-s chair stand, and 6-min walk tests, assessed at baseline and 12 weeks. Twenty-three participants completed follow-up assessments. Mixed analysis of variance models examined differences in outcomes. The BG displayed improvements in all measures at follow-up and significantly improved compared with CG on, isokinetic PT60, PT180 (p = 0.02), RFD (p < 0.05), balance with eyes closed (p values range .02 to <.01) and TUG (p = 0.03), all with medium effect sizes. No changes in outcome measures were observed in the CG. BEC improved strength, power, balance, and functionality in older women. The BEC warrants further investigation as a fall prevention intervention.

  5. In vivo assessment of contractile strength distinguishes differential gene function in skeletal muscle of zebrafish larvae.

    PubMed

    Martin, Brit L; Gallagher, Thomas L; Rastogi, Neha; Davis, Jonathan P; Beattie, Christine E; Amacher, Sharon L; Janssen, Paul M L

    2015-10-01

    The accessible genetics and extensive skeletal musculature of the zebrafish make it a versatile and increasingly used model for studying muscle contraction. We here describe the development of an in vivo assay for measuring the contractile force of intact zebrafish at the larval stage. In addition, as proof of applicability, we have used this assay to quantify contractile strength of zebrafish larvae in a morphant model of deranged rbfox function. Average maximum tetanic (180 Hz) whole body forces produced by wild-type larvae at 2, 3, 4, and 5 days postfertilization amounted to 3.0, 7.2, 9.1, and 10.8 mN, respectively. To compare at potentially different stages of muscle development, we developed an immunohistological assay for empirically determining the cross-sectional area of larval trunk skeletal muscle to quantify muscle-specific force per cross-sectional area. At 4-5 days postfertilization, specific force amounts to ∼ 300 mN/mm(2), which is similar to fully developed adult mammalian skeletal muscle. We used these assays to measure contractile strength in zebrafish singly or doubly deficient for two rbfox paralogs, rbfox1l and rbfox2, which encode RNA-binding factors shown previously to modulate muscle function and muscle-specific splicing. We found rbfox2 morphants produce maximal tetanic forces similar to wild-type larvae, whereas rbfox1l morphants demonstrate significantly impaired function. rbfox1l/rbfox2 morphants are paralyzed, and their lack of contractile force production in our assay suggests that paralysis is a muscle-autonomous defect. These quantitative functional results allow measurement of muscle-specific phenotypes independent of neural input.

  6. Quadriceps Strength Asymmetry Following ACL Reconstruction Alters Knee Joint Biomechanics and Functional Performance at Time of Return to Activity

    PubMed Central

    Palmieri-Smith, RM; Lepley, LK

    2016-01-01

    Background Quadriceps strength deficits are observed clinically following anterior cruciate injury and reconstruction and are often not overcome despite rehabilitation. Given that quadriceps strength may be important for achieving symmetrical joint biomechanics and promoting long-term joint health, determining the magnitude of strength deficits that lead to altered mechanics is critical. Purpose To determine if the magnitude of quadriceps strength asymmetry alters knee and hip biomechanical symmetry, as well as functional performance and self-reported function. Study Design Cross-Sectional study. Methods Seventy-three patients were tested at the time they were cleared for return to activity following ACL reconstruction. Quadriceps strength and activation, scores on the International Knee Documentation Committee form, the hop for distance test, and sagittal plane lower extremity biomechanics were recorded while patients completed a single-legged hop. Results Patients with high and moderate quadriceps strength symmetry had larger central activation ratios as well as greater limb symmetry indices on the hop for distance compared to patients with low quadriceps strength symmetry (P<0.05). Similarly, knee flexion angle and external moment symmetry was higher in the patients with high and moderate quadriceps symmetry compared to those with low symmetry (P<0.05). Quadriceps strength was found to be associated with sagittal plane knee angle and moment symmetry (P<0.05). Conclusion Patients with low quadriceps strength displayed greater movement asymmetries at the knee in the sagittal plane. Quadriceps strength was related to movement asymmetries and functional performance. Rehabilitation following ACL reconstruction needs to focus on maximizing quadriceps strength, which likely will lead to more symmetrical knee biomechanics. PMID:25883169

  7. Large-scale deformed QRPA calculations of the gamma-ray strength function based on a Gogny force

    NASA Astrophysics Data System (ADS)

    Martini, M.; Goriely, S.; Hilaire, S.; Péru, S.; Minato, F.

    2016-01-01

    The dipole excitations of nuclei play an important role in nuclear astrophysics processes in connection with the photoabsorption and the radiative neutron capture that take place in stellar environment. We present here the results of a large-scale axially-symmetric deformed QRPA calculation of the γ-ray strength function based on the finite-range Gogny force. The newly determined γ-ray strength is compared with experimental photoabsorption data for spherical as well as deformed nuclei. Predictions of γ-ray strength functions and Maxwellian-averaged neutron capture rates for Sn isotopes are also discussed.

  8. Effects of smoking on chest expansion, lung function, and respiratory muscle strength of youths.

    PubMed

    Tantisuwat, Anong; Thaveeratitham, Premtip

    2014-02-01

    [Purpose] Smoking has a direct effect on the respiratory system. The rate of cigarette smoking among young people has continued to increase steadily. The present study quantified and compared the respiratory function of smoking and non-smoking youths. [Subjects] Smoking and non-smoking male participants aged between 15 to 18 years were recruited (n=34 per group). [Methods] Participants were asked to complete a questionnaire relating to smoking habits and the Fagerström test for nicotine dependence questionnaire, and their respiratory function was tested (measurement of chest expansion, lung function test with a spirometer, and assessment of respiratory muscle strength). [Results] All respiratory function tests demonstrated significant differences between the smoking and non-smoking groups. Smokers initiated cigarette smoking between the ages of 15 to 18 years. The most common duration of cigarette smoking was 1-3 years and the degree of nicotine dependence among the youths was at a low level. [Conclusion] This study's findings show that the early effects of cigarette smoking found in youths can lead to problems with the respiratory system. Such information can be used to illustrate the harm of smoking and should be used to encourage young people to quit or avoid cigarette smoking. PMID:24648624

  9. Effects of Smoking on Chest Expansion, Lung Function, and Respiratory Muscle Strength of Youths

    PubMed Central

    Tantisuwat, Anong; Thaveeratitham, Premtip

    2014-01-01

    [Purpose] Smoking has a direct effect on the respiratory system. The rate of cigarette smoking among young people has continued to increase steadily. The present study quantified and compared the respiratory function of smoking and non-smoking youths. [Subjects] Smoking and non-smoking male participants aged between 15 to 18 years were recruited (n=34 per group). [Methods] Participants were asked to complete a questionnaire relating to smoking habits and the Fagerström test for nicotine dependence questionnaire, and their respiratory function was tested (measurement of chest expansion, lung function test with a spirometer, and assessment of respiratory muscle strength). [Results] All respiratory function tests demonstrated significant differences between the smoking and non-smoking groups. Smokers initiated cigarette smoking between the ages of 15 to 18 years. The most common duration of cigarette smoking was 1-3 years and the degree of nicotine dependence among the youths was at a low level. [Conclusion] This study’s findings show that the early effects of cigarette smoking found in youths can lead to problems with the respiratory system. Such information can be used to illustrate the harm of smoking and should be used to encourage young people to quit or avoid cigarette smoking. PMID:24648624

  10. Photon Strength Functions from Two-Step γ Cascades Experiment on 155,157Gd

    NASA Astrophysics Data System (ADS)

    Kroll, J.; Valenta, S.; Krtička, M.; Bečvář, F.; Tomandl, I.; Mitchell, G. E.

    2015-05-01

    Spectra of two-step γ cascades following neutron capture in 155,157Gd were measured using the two- HPGe-detector facility installed at a pure subthermal neutron beam of the LVR-15 reactor in ˇež near Prague. The main objective of this experiment was to get new information on photon strength functions with the emphasis put on the role of M1 scissors mode vibration. An analysis of accumulated γ-ray spectra, made within the statistical model, leads to the conclusion that the scissors mode significantly affects γ decay of all states of studied nuclei. The obtained results for energy, damping width and summed B(M1) ↑ strength of the scissors mode are compared with what has been deduced from neutron capture experiments performed at DANCE detector installed in Los Alamos National Laboratory, NRF data for the ground state scissors mode and from the data on 3He-induced reactions using the so-called Oslo method.

  11. Photon strength functions of 156Gd from radiative capture of resonance neutrons

    NASA Astrophysics Data System (ADS)

    Baramsai, B.; Kroll, J.; Mitchell, G. E.; Agvaanluvsan, U.; Bečvář, F.; Bredeweg, T. A.; Chyzh, A.; Couture, A.; Dashdorj, D.; Haight, R. C.; Jandel, M.; Keksis, A. L.; Krtička, M.; O'Donnell, J. M.; Rundberg, R. S.; Ullmann, J. L.; Vieira, D. J.; Walker, C. L.

    2013-04-01

    The 155Gd(n,γ) reaction was measured with the DANCE γ-ray calorimeter (consisting of 160 BaF2 scintillation detectors) at the Los Alamos Neutron Science Center. The γ-ray energy spectra for different multiplicities were obtained for the s-wave resonances. The shapes of these spectra were compared with simulations based on the use of the dicebox statistical model code. Simulations showed that the photon strength functions (PSFs) successfully describing the decay of 156Gd are very similar to the PSFs describing the decay of previously published 158Gd results. It was demonstrated that the scissors mode is required not only for the ground-state transitions, but also for transitions between excited states.

  12. Influence of finger amputation on grip strength and objectively measured hand function: a descriptive cross-sectional study.

    PubMed

    Kuret, Zala; Burger, Helena; Vidmar, Gaj

    2015-06-01

    Finger amputations are common and hands are essential for functioning, but studies on factors influencing functioning after finger amputation are lacking. Therefore, we aimed to explore the influence of the number and level of amputated fingers on hand function and grip strength. A prospective descriptive cross-sectional study involving 69 patients with partial or complete amputation of one or more fingers of one hand was carried out. The function of both hands was assessed using the Southampton Hand Assessment Procedure test; grip strength was measured in 42 patients. We confirmed that finger amputation worsens hand function (especially tripod and tip pinch) and reduces grip strength, whereby the extent of the worsening depends on amputation type - it is the smallest after thumb amputation and the largest after amputation of the index finger and fingers III-V. However, because of the variety of amputation types, we recommend that future studies either involve very large samples or focus on specific amputations.

  13. Knee extension strength and post-operative functional prediction in quadriceps resection for soft-tissue sarcoma of the thigh

    PubMed Central

    Tanaka, A.; Aoki, K.; Kito, M.; Okamoto, M.; Suzuki, S.; Momose, T.; Kato, H.

    2016-01-01

    Objectives Our objective was to predict the knee extension strength and post-operative function in quadriceps resection for soft-tissue sarcoma of the thigh. Methods A total of 18 patients (14 men, four women) underwent total or partial quadriceps resection for soft-tissue sarcoma of the thigh between 2002 and 2014. The number of resected quadriceps was surveyed, knee extension strength was measured with the Biodex isokinetic dynamometer system (affected side/unaffected side) and relationships between these were examined. The Musculoskeletal Tumor Society (MSTS) score, Toronto Extremity Salvage Score (TESS), European Quality of Life-5 Dimensions (EQ-5D) score and the Short Form 8 were used to evaluate post-operative function and examine correlations with extension strength. The cutoff value for extension strength to expect good post-operative function was also calculated using a receiver operating characteristic (ROC) curve and Fisher’s exact test. Results Extension strength decreased when the number of resected quadriceps increased (p < 0.001), and was associated with lower MSTS score, TESS and EQ-5D (p = 0.004, p = 0.005, p = 0.006, respectively). Based on the functional evaluation scales, the cutoff value of extension strength was 56.2%, the equivalent to muscle strength with resection of up to two muscles. Conclusion Good post-operative results can be expected if at least two quadriceps muscles are preserved. Cite this article: A. Tanaka, Y. Yoshimura, K. Aoki, M. Kito, M. Okamoto, S. Suzuki, T. Momose, H. Kato. Knee extension strength and post-operative functional prediction in quadriceps resection for soft-tissue sarcoma of the thigh. Bone Joint Res 2016;5:232–238. DOI: 10.1302/2046-3758.56.2000631. PMID:27317788

  14. The effects of a strategic strength resistance exercise program on the isokinetic muscular function of the ankle

    PubMed Central

    Jeon, Kyoung-Kyu; Kim, Tae-Young; Lee, Sang-Ho

    2015-01-01

    [Purpose] The purpose of this study was to investigate the effects of a strategic strength resistance exercise program on the isokinetic muscular function of the ankle joint. [Subjects] This study included 22 males in their twenties who were diagnosed with functional injury of the ankle joint. [Methods] To strengthen plantar flexion and dorsiflexion of the ankle joint, 8 weeks of weight, resistance band, and plyometric training, and training using props were performed. [Results] A medical examination by interview indicated that pain, swelling, instability, running, and support capacity of the ankle joint significantly improved with the strategic strength resistance exercise program. For the isokinetic peak torque of the ankles, significant differences were observed in right plantar flexion and bilateral dorsiflexion. [Conclusion] The strategic strength resistance exercise program is highly recommended for the functional stability of the ankle joint. Efficient exercise therapy is useful for muscle damage prevention, muscle strengthening, and functional interventions. PMID:26644696

  15. Relationships between Isometric Muscle Strength, Gait Parameters, and Gross Motor Function Measure in Patients with Cerebral Palsy

    PubMed Central

    Shin, Hyung-Ik; Sung, Ki Hyuk; Chung, Chin Youb; Lee, Kyoung Min; Lee, Seung Yeol; Lee, In Hyeok

    2016-01-01

    Purpose This study investigated the correlation between isometric muscle strength, gross motor function, and gait parameters in patients with spastic cerebral palsy and to find which muscle groups play an important role for gait pattern in a flexed knee gait. Materials and Methods Twenty-four ambulatory patients (mean age, 10.0 years) with spastic cerebral palsy who were scheduled for single event multilevel surgery, including distal hamstring lengthening, were included. Preoperatively, peak isometric muscle strength was measured for the hip flexor, hip extensor, knee flexor, and knee extensor muscle groups using a handheld dynamometer, and three-dimensional (3D) gait analysis and gross motor function measure (GMFM) scoring were also performed. Correlations between peak isometric strength and GMFM, gait kinematics, and gait kinetics were analyzed. Results Peak isometric muscle strength of all muscle groups was not related to the GMFM score and the gross motor function classification system level. Peak isometric strength of the hip extensor and knee extensor was significantly correlated with the mean pelvic tilt (r=-0.588, p=0.003 and r=-0.436, p=0.033) and maximum pelvic obliquity (r=-0.450, p=0.031 and r=-0.419, p=0.041). There were significant correlations between peak isometric strength of the knee extensor and peak knee extensor moment in early stance (r=0.467, p=0.021) and in terminal stance (r=0.416, p=0.043). Conclusion There is no correlation between muscle strength and gross motor function. However, this study showed that muscle strength, especially of the extensor muscle group of the hip and knee joints, might play a critical role in gait by stabilizing pelvic motion and decreasing energy consumption in a flexed knee gait. PMID:26632404

  16. Evaluation of electron capture reaction rates in Ni isotopes in stellar environments

    SciTech Connect

    Suzuki, Toshio; Honma, Michio; Mao, Helene; Otsuka, Takaharu; Kajino, Toshitaka

    2011-04-15

    Electron capture rates in Ni isotopes are studied in stellar environments, that is, at high densities and high temperatures during the core-collapse and postbounce explosive nucleosynthesis in supernovae. Reaction rates in {sup 58}Ni and {sup 60}Ni, as well as in {sup 56}Ni, {sup 62}Ni, and {sup 64}Ni, are evaluated by shell-model calculations with the use of a new shell-model Hamiltonian in the fp shell, GXPF1J. While the previous shell-model calculations failed to reproduce the measured peaks of Gamow-Teller strength in {sup 58}Ni and {sup 60}Ni, the present new Hamiltonian is found to reproduce them very well, as well as the capture rates obtained from the observed strengths. Strengths and energies of the Gamow-Teller transitions in {sup 56}Ni, {sup 62}Ni, and {sup 64}Ni are also found to be consistent with the observations.

  17. The strength of the HIV-1 3' splice sites affects Rev function

    PubMed Central

    Kammler, Susanne; Otte, Marianne; Hauber, Ilona; Kjems, Jørgen; Hauber, Joachim; Schaal, Heiner

    2006-01-01

    Background The HIV-1 Rev protein is a key component in the early to late switch in HIV-1 splicing from early intronless (e.g. tat, rev) to late intron-containing Rev-dependent (e.g. gag, vif, env) transcripts. Previous results suggested that cis-acting sequences and inefficient 5' and 3' splice sites are a prerequisite for Rev function. However, we and other groups have shown that two of the HIV-1 5' splice sites, D1 and D4, are efficiently used in vitro and in vivo. Here, we focus on the efficiency of the HIV-1 3' splice sites taking into consideration to what extent their intrinsic efficiencies are modulated by their downstream cis-acting exonic sequences. Furthermore, we delineate their role in RNA stabilization and Rev function. Results In the presence of an efficient upstream 5' splice site the integrity of the 3' splice site is not essential for Rev function whereas an efficient 3' splice site impairs Rev function. The detrimental effect of a strong 3' splice site on the amount of Rev-dependent intron-containing HIV-1 glycoprotein coding (env) mRNA is not compensatable by weakening the strength of the upstream 5' splice site. Swapping the HIV-1 3' splice sites in an RRE-containing minigene, we found a 3' splice site usage which was variably dependent on the presence of the usual downstream exonic sequence. The most evident activation of 3' splice site usage by its usual downstream exonic sequence was observed for 3' splice site A1 which was turned from an intrinsic very weak 3' splice site into the most active 3' splice site, even abolishing Rev activity. Performing pull-down experiments with nuclear extracts of HeLa cells we identified a novel ASF/SF2-dependent exonic splicing enhancer (ESE) within HIV-1 exon 2 consisting of a heptameric sequence motif occurring twice (M1 and M2) within this short non-coding leader exon. Single point mutation of M1 within an infectious molecular clone is detrimental for HIV-1 exon 2 recognition without affecting Rev

  18. Effect of traditional resistance and power training using rated perceived exertion for enhancement of muscle strength, power, and functional performance.

    PubMed

    Tiggemann, Carlos Leandro; Dias, Caroline Pieta; Radaelli, Regis; Massa, Jéssica Cassales; Bortoluzzi, Rafael; Schoenell, Maira Cristina Wolf; Noll, Matias; Alberton, Cristine Lima; Kruel, Luiz Fernando Martins

    2016-04-01

    The present study compared the effects of 12 weeks of traditional resistance training and power training using rated perceived exertion (RPE) to determine training intensity on improvements in strength, muscle power, and ability to perform functional task in older women. Thirty healthy elderly women (60-75 years) were randomly assigned to traditional resistance training group (TRT; n = 15) or power training group (PT; n = 15). Participants trained twice a week for 12 weeks using six exercises. The training protocol was designed to ascertain that participants exercised at an RPE of 13-18 (on a 6-20 scale). Maximal dynamic strength, muscle power, and functional performance of lower limb muscles were assessed. Maximal dynamic strength muscle strength leg press (≈58 %) and knee extension (≈20 %) increased significantly (p < 0.001) and similarly in both groups after training. Muscle power also increased with training (≈27 %; p < 0.05), with no difference between groups. Both groups also improved their functional performance after training period (≈13 %; p < 0.001), with no difference between groups. The present study showed that TRT and PT using RPE scale to control intensity were significantly and similarly effective in improving maximal strength, muscle power, and functional performance of lower limbs in elderly women.

  19. Effect of Isometric Quadriceps Exercise on Muscle Strength, Pain, and Function in Patients with Knee Osteoarthritis: A Randomized Controlled Study

    PubMed Central

    Anwer, Shahnawaz; Alghadir, Ahmad

    2014-01-01

    [Purpose] The aim of present study was to investigate the effects of isometric quadriceps exercise on muscle strength, pain, and function in knee osteoarthritis. [Subjects and Methods] Outpatients (N=42, 21 per group; age range 40–65 years; 13 men and 29 women) with osteoarthritis of the knee participated in the study. The experimental group performed isometric exercises including isometric quadriceps, straight leg raising, and isometric hip adduction exercise 5 days a week for 5 weeks, whereas the control group did not performed any exercise program. The outcome measures or dependent variables selected for this study were pain intensity, isometric quadriceps strength, and knee function. These variables were measured using the Numerical Rating Scale (NRS), strength gauge device, and reduced WOMAC index, respectively. All the measurements were taken at baseline (week 0) and at the end of the trial at week 5. [Results] In between-group comparisons, the maximum isometric quadriceps strength, reduction in pain intensity, and improvement in function in the isometric exercise group at the end of the 5th week were significantly greater than those of the control group (p<0.05). [Conclusion] The 5-week isometric quadriceps exercise program showed beneficial effects on quadriceps muscle strength, pain, and functional disability in patients with osteoarthritis of the knee. PMID:24926143

  20. Giant dipole resonance in 88Mo from phonon damping model strength functions averaged over temperature and angular momentum distributions

    NASA Astrophysics Data System (ADS)

    Dinh Dang, N.; Ciemala, M.; Kmiecik, M.; Maj, A.

    2013-05-01

    The line shapes of giant dipole resonance (GDR) in the decay of the compound nucleus 88Mo, which is formed after the fusion-evaporation reaction 48Ti + 40Ca at various excitation energies E* from 58 to 308 MeV, are generated by averaging the GDR strength functions predicted within the phonon damping model (PDM) using the empirical probabilities for temperature and angular momentum. The average strength functions are compared with the PDM strength functions calculated at the mean temperature and mean angular momentum, which are obtained by averaging the values of temperature and angular momentum using the same temperature and angular momentum probability distributions, respectively. It is seen that these two ways of generating the GDR linear line shape yield very similar results. It is also shown that the GDR width approaches a saturation at angular momentum J≥ 50 ℏ at T=4 MeV and at J≥ 70 ℏ at any T.

  1. The effects of strength exercise and walking on lumbar function, pain level, and body composition in chronic back pain patients

    PubMed Central

    Lee, Jung-Seok; Kang, Suh-Jung

    2016-01-01

    The beneficial effects of a strength exercise program and a combined exercise program of strength training plus walking were examined in overweight with chronic back pain patients. The participants were randomly placed in the strength exercise group (SEG, n=15), combined exercise group (CEG, n=15), and control group (CG, n=6). All subjects performed exercise twice per week, 50 min per session with a professional instructors for 12 weeks. In order to evaluate exercise intervention effects, lumbar function was measured by back strength and flexibility. Roland-Morris disability questionnaire (RMDQ) and visual analogue scale (VAS) were used to evaluate pain level. Fat and muscle mass were measured to compare body composition changes. All measurements were performed before and after 12 weeks of exercise program. Lumbar function: Back strength was significantly different over time, and significant time×group differences were found between SEG and CG and, CEG and CG. Pain disorder degree: VAS showed a significant group difference, and significant time×group differences were shown between SEG and CG, and CEG and CG. Also, RMDG showed a significant difference between CEG and CG. Body composition: Fat mass was significantly different over time×group between SEG and CG. In conclusion, participating in strength and walking exercises were beneficial to improve lumbar function. Also, the combined exercise program was more effective for reducing pain levels than the strength exercise. Finally, fat mass was reduced in this study and this may play a possible role in the improvement of lumbar function and reduction in low back pain. PMID:27807526

  2. Calmodulin Methyltransferase Is Required for Growth, Muscle Strength, Somatosensory Development and Brain Function.

    PubMed

    Haziza, Sitvanit; Magnani, Roberta; Lan, Dima; Keinan, Omer; Saada, Ann; Hershkovitz, Eli; Yanay, Nurit; Cohen, Yoram; Nevo, Yoram; Houtz, Robert L; Sheffield, Val C; Golan, Hava; Parvari, Ruti

    2015-08-01

    Calmodulin lysine methyl transferase (CaM KMT) is ubiquitously expressed and highly conserved from plants to vertebrates. CaM is frequently trimethylated at Lys-115, however, the role of CaM methylation in vertebrates has not been studied. CaM KMT was found to be homozygously deleted in the 2P21 deletion syndrome that includes 4 genes. These patients present with cystinuria, severe intellectual disabilities, hypotonia, mitochondrial disease and facial dysmorphism. Two siblings with deletion of three of the genes included in the 2P21 deletion syndrome presented with cystinuria, hypotonia, a mild/moderate mental retardation and a respiratory chain complex IV deficiency. To be able to attribute the functional significance of the methylation of CaM in the mouse and the contribution of CaM KMT to the clinical presentation of the 2p21deletion patients, we produced a mouse model lacking only CaM KMT with deletion borders as in the human 2p21deletion syndrome. No compensatory activity for CaM methylation was found. Impairment of complexes I and IV, and less significantly III, of the mitochondrial respiratory chain was more pronounced in the brain than in muscle. CaM KMT is essential for normal body growth and somatosensory development, as well as for the proper functioning of the adult mouse brain. Developmental delay was demonstrated for somatosensory function and for complex behavior, which involved both basal motor function and motivation. The mutant mice also had deficits in motor learning, complex coordination and learning of aversive stimuli. The mouse model contributes to the evaluation of the role of methylated CaM. CaM methylation appears to have a role in growth, muscle strength, somatosensory development and brain function. The current study has clinical implications for human patients. Patients presenting slow growth and muscle weakness that could result from a mitochondrial impairment and mental retardation should be considered for sequence analysis of the Ca

  3. Calmodulin Methyltransferase Is Required for Growth, Muscle Strength, Somatosensory Development and Brain Function

    PubMed Central

    Haziza, Sitvanit; Magnani, Roberta; Lan, Dima; Keinan, Omer; Saada, Ann; Hershkovitz, Eli; Yanay, Nurit; Cohen, Yoram; Nevo, Yoram; Houtz, Robert L.; Sheffield, Val C.; Golan, Hava; Parvari, Ruti

    2015-01-01

    Calmodulin lysine methyl transferase (CaM KMT) is ubiquitously expressed and highly conserved from plants to vertebrates. CaM is frequently trimethylated at Lys-115, however, the role of CaM methylation in vertebrates has not been studied. CaM KMT was found to be homozygously deleted in the 2P21 deletion syndrome that includes 4 genes. These patients present with cystinuria, severe intellectual disabilities, hypotonia, mitochondrial disease and facial dysmorphism. Two siblings with deletion of three of the genes included in the 2P21 deletion syndrome presented with cystinuria, hypotonia, a mild/moderate mental retardation and a respiratory chain complex IV deficiency. To be able to attribute the functional significance of the methylation of CaM in the mouse and the contribution of CaM KMT to the clinical presentation of the 2p21deletion patients, we produced a mouse model lacking only CaM KMT with deletion borders as in the human 2p21deletion syndrome. No compensatory activity for CaM methylation was found. Impairment of complexes I and IV, and less significantly III, of the mitochondrial respiratory chain was more pronounced in the brain than in muscle. CaM KMT is essential for normal body growth and somatosensory development, as well as for the proper functioning of the adult mouse brain. Developmental delay was demonstrated for somatosensory function and for complex behavior, which involved both basal motor function and motivation. The mutant mice also had deficits in motor learning, complex coordination and learning of aversive stimuli. The mouse model contributes to the evaluation of the role of methylated CaM. CaM methylation appears to have a role in growth, muscle strength, somatosensory development and brain function. The current study has clinical implications for human patients. Patients presenting slow growth and muscle weakness that could result from a mitochondrial impairment and mental retardation should be considered for sequence analysis of the Ca

  4. Is better preservation of eccentric strength after stroke due to altered prefrontal function?

    PubMed

    Hedlund, Mattias; Lindström, Britta; Sojka, Peter; Lundström, Ronnie; Boraxbekk, Carl-Johan

    2016-01-01

    Ventrolateral prefrontal cortex (VLPFC) is part of a network that exerts inhibitory control over the motor cortex (MC). Recently, we demonstrated that VLPFC was more activated during imagined maximum eccentric than during imagined concentric contractions in healthy participants. This was accompanied with lower activation levels within motor regions during imagined eccentric contractions. The aim was to test a novel hypothesis of an involvement of VLPFC in contraction mode-specific modulation of force. Functional magnetic resonance imaging was used to examine differences in VLPFC and motor regions during the concentric and the eccentric phases of imagined maximum contractions in a selected sample of subjects with stroke (n = 4). The subjects were included as they exhibited disturbed modulation of force. The previously demonstrated pattern within VLPFC was evident only on the contralesional hemisphere. On the ipsilesional hemisphere, the recruitment in VLPFC was similar for both modes of contractions. The findings support a hypothesis of the involvement of VLPFC in contraction mode-specific modulation of maximum force production. A disturbance of this system might underlie the lack of contraction mode-specific modulation commonly found among stroke subjects, often expressed as an increased ratio between eccentric and concentric strength.

  5. Mortality displacement as a function of heat event strength in 7 US cities.

    PubMed

    Saha, Michael V; Davis, Robert E; Hondula, David M

    2014-02-15

    Mortality rates increase immediately after periods of high air temperature. In the days and weeks after heat events, time series may exhibit mortality displacement-periods of lower than expected mortality. We examined all-cause mortality and meteorological data from 1980 to 2009 in the cities of Atlanta, Georgia; Boston, Massachusetts; Minneapolis-St. Paul, Minnesota; Philadelphia, Pennsylvania; Phoenix, Arizona; Seattle, Washington; and St. Louis, Missouri. We modeled baseline mortality using a generalized additive model. Heat waves were defined as periods of 3 or more consecutive days in which the apparent temperature exceeded a variable percentile. For each heat wave, we calculated the sum of excess and deficit mortality. Mortality displacement, which is the ratio of grand sum deficit to grand sum excess mortality, decreased as a function of event strength in all cities. Displacement was close to 1.00 for the weakest events. At the highest temperatures, displacement varied from 0.35 (95% confidence interval: 0.21, 0.55) to 0.75 (95% confidence interval: 0.54, 0.97). We found strong evidence of acclimatization across cities. Without consideration of displacement effects, the net impacts of heat-wave mortality are likely to be significant overestimations. A statistically significant positive relationship between the onset temperature of nondisplaced heat mortality and mean warm-season temperature (R(2) = 0.78, P < 0.01) suggests that heat mortality thresholds may be predictable across cities.

  6. Study of the Photon Strength Functions for Gadolinium Isotopes with the DANCE Array

    SciTech Connect

    Dashdorj, D.; Mitchell, G. E.; Baramsai, B.; Chankova, R.; Chyzh, A.; Walker, C.; Agvaanluvsan, U.; Becker, J. A.; Parker, W.; Sleaford, B.; Wu, C. Y.; Bredeweg, T. A.; Couture, A.; Haight, R. C.; Jandel, M.; Rundberg, R. S.; Ullmann, J. L.; Vieira, D. J.; Wouters, J. M.; Krticka, M.

    2009-03-10

    The gadolinium isotopes are interesting for reactor applications as well as for medicine and astrophysics. The gadolinium isotopes have some of the largest neutron capture cross sections. As a consequence they are used in the control rod in reactor fuel assembly. From the basic science point of view, there are seven stable isotopes of gadolinium with varying degrees of deformation. Therefore they provide a good testing ground for the study of deformation dependent structure such as the scissors mode. Decay gamma rays following neutron capture on Gd isotopes are detected by the DANCE array, which is located at flight path 14 at the Lujan Neutron Scattering Center at Los Alamos National Laboratory. The high segmentation and close packing of the detector array enable gamma-ray multiplicity measurements. The calorimetric properties of the DANCE array coupled with the neutron time-of-flight technique enables one to gate on a specific resonance of a specific isotope in the time-of-flight spectrum and obtain the summed energy spectrum for that isotope. The singles gamma-ray spectrum for each multiplicity can be separated by their DANCE cluster multiplicity. Various photon strength function models are used for comparison with experimentally measured DANCE data and provide insight for understanding the statistical decay properties of deformed nuclei.

  7. Measuring the strength of dermal fibroblast attachment to functionalized titanium alloys in vitro.

    PubMed

    Pendegrass, Catherine J; Middleton, Claire A; Gordon, David; Jacob, Josh; Blunn, Gordon W

    2010-03-01

    The success of intraosseous transcutaneous amputation prostheses (ITAP) relies on soft tissue attachment to prevent infection which leads to implant failure. Fibronectin (Fn) has been shown to enhance dermal fibroblast attachment in vitro, however measurement of cell attachment strength has been indirect; using cell area and immunolocalization of focal adhesion components. In this study, we have developed a flow apparatus to assess the biophysical strength of cell attachment to biomaterials used in ITAP. We have demonstrated that dermal fibroblast attachment strength increases significantly up to 96 h and that data from direct and indirect methods of assessing cell attachment strength have a significant positive correlation. Additionally, we have used direct and indirect assessment methods to demonstrate that dermal fibroblast attachment strength is significantly greater on fibronectin-coated titanium alloy compared with uncoated controls at 1, 4, and 24 hours.

  8. Comparison of pulmonary function and back muscle strength according to the degree of spinal curvature of healthy adults.

    PubMed

    You, Jae Eung; Lee, Hye Young; Kim, Kyoung

    2015-06-01

    [Purpose] Degree of curvature on the spine is known to affect respiratory function and back muscle activation. We compared pulmonary function and back muscle strength according to the degree of curvature of the spine of healthy adults. [Subjects and Methods] Twenty-three healthy volunteers were enrolled. They were divided into two groups according to the degree of curvature of the spine: the below 2° group, and the above 2° group. The degree of curvature was assessed using the Adams forward bending test and a scoliometer. A pulmonary function test (PFT) was conducted, and back muscle strength was measured. [Results] No significant differences in PFT were found between the below 2° group and the above 2° group, in terms of forced vital capacity (FVC), forced expiratory volume in one second (FEV1), ratio of forced expiratory volume in one second to forced vital capacity (FEV1/FVC), or peak expiratory flow (PEF). However, back muscle strength in the below 2 group was significantly higher than that of the above 2 group. [Conclusion] Our findings indicate that the degree of curvature of the spine is associated with back muscle strength in subjects who have spinal curvature within the normal range. Therefore, evaluation and treatment of back muscle strength might be helpful for preventing the progress of curvature of the spine in adolescents with potential scoliosis. PMID:26180321

  9. Strength of bed nets as function of denier, knitting pattern, texturizing and polymer

    PubMed Central

    2011-01-01

    Background Bursting strength is a standard method for evaluating mosquito net strength. This article suggests that tension strength with one grab and one hook better represent how holes are generated in bed nets in real life. Methods Measurements of bursting strength and tension strengths in the two directions are analysed for eight model nets created for the study. The nets were made in the most commonly used denier (75 and 100 D) and mesh (156 holes/inch2) for multifilament polyester yarns, texturized or not, and with 4 or 6 sided holes. All were made from one polyester quality. Data was arranged in a randomized, complete block design and analysed for significant variables and their interactions. Data was then subjected to regression analyses using net square metre weight as a weighting factor with stepwise removal of variables. This revealed how the four textile variables interacted and allowed for making predictions for the strength of commercial nets in polyester or polyethylene. Results For the model nets, higher denier provided higher bursting strength and tension strengths, texturizing weakened nets and four-sided holes were stronger than six-sided holes. Even when compensating for square metre weight, 100 D nets are stronger than 75 D nets. Results for the commercial polyester net nets are less clear, probably because of different qualities of polyester. Tensile strength: a 75 denier net knitted tightly to provide the same square metre weight as a standard 100 denier net therefore does not obtain the same strength. Polyethylene nets are made of mono-fibre yarns and, therefore, have higher tension strength in both directions than multifilament polyester nets. For bursting strength results overlap for 100 denier yarns of both yarn types. As a class, commercial polyethylene nets are stronger than commercial polyester net whatever method is used for evaluation. Conclusion Tension strength measured in the length and width directions of the net using one hook

  10. Lower limb muscle strength is associated with functional performance and quality of life in patients with systemic sclerosis

    PubMed Central

    Lima, Tatiana R. L.; Guimarães, Fernando S.; Carvalho, Mara N.; Sousa, Thaís L. M.; Menezes, Sara L. S.; Lopes, Agnaldo J.

    2015-01-01

    Background: Complaints of peripheral muscle weakness are quite common in patients with systemic sclerosis (SSc). It is likely that the muscle impairments may reduce the patients' exercise performance, which in turn may decrease their functional capacity and exert a direct impact on their quality of life. Objectives: To assess the peripheral and respiratory muscle strength in individuals with SSc and to investigate their correlation with the 6-min walk distance (6MWD) and quality of life measurements. Moreover, we aimed to characterize their nutritional status, pulmonary function, functional capacity, and quality of life compared to the controls. Method: The present cross-sectional study included 20 patients with SSc and 20 control subjects. All of the participants were subjected to isometric dynamometry, surface electromyography, bioelectrical impedance analysis, pulmonary function testing, and the 6-min walk test. Patients with SSc also responded to the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) and the Health Assessment Questionnaire Disability Index (HAQ-DI). Results: The individuals with SSc exhibited a reduction in quadriceps strength (p=0.0001), increased quadriceps fatigability (p=0.034), impaired pulmonary function, and a reduced 6MWD (p=0.0001) compared to the controls. Quadriceps strength was significantly correlated with the 6MWD (Rho=0.719; p=0.0004) and the HAQ-DI (Rho=-0.622; p=0.003). We also found significant correlations between quadriceps fatigability and maximal inspiratory (Rho=0.684; p=0.0009) and maximal expiratory (Rho=0.472; p=0.035) pressure. Conclusions: Patients with SSc exhibited reduced respiratory muscle and quadriceps strength and an increase in its fatigability. In these individuals, there was a relationship between quadriceps strength, functional capacity, and quality of life. PMID:25789555

  11. Prognostic value of physical function tests: hand grip strength and six-minute walking test in elderly hospitalized patients.

    PubMed

    Martín-Ponce, Esther; Hernández-Betancor, Iván; González-Reimers, Emilio; Hernández-Luis, Rubén; Martínez-Riera, Antonio; Santolaria, Francisco

    2014-01-01

    To discern if physical function test are better mortality predictors than muscle mass in elderly hospitalized patients, we analyzed the prognostic value of muscle mass malnutrition and compared it with physical muscle function tests, including the six-minute walking test (6 MWT) and hand grip strength. We included the ankle brachial index (ABI) to assess arterial disease, related to muscle atrophy due to hypoperfusion. We also analyzed the relationship of ABI with malnutrition, physical function tests and survival. We studied 310 hospitalized patients older than 60 years. To assess nutritional status, we determined BMI, triceps skinfold and mid-arm muscle area; we performed a subjective nutritional assessment; and evaluated the degree of inflammatory stress. We assessed physical function by hand grip strength and 6 MWT. We evaluated arterial disease by ABI. Forty-one patients died during hospitalization; 269 were discharged and followed for a mean 808 days, reaching a mortality of 49%. Muscle malnutrition was frequent and was related to mortality, but the best predictors were physical function tests: inability to perform the 6 MWT and low handgrip strength. Function tests were closely related to each other and correlated with nutritional data. Reduced ABI was related to impaired nutritional status, physical function tests and mortality.

  12. Knee Muscle Strength at Varying Angular Velocities and Associations with Gross Motor Function in Ambulatory Children with Cerebral Palsy

    ERIC Educational Resources Information Center

    Hong, Wei-Hsien; Chen, Hseih-Ching; Shen, I-Hsuan; Chen, Chung-Yao; Chen, Chia-Ling; Chung, Chia-Ying

    2012-01-01

    The aim of this study was to evaluate the relationships of muscle strength at different angular velocities and gross motor functions in ambulatory children with cerebral palsy (CP). This study included 33 ambulatory children with spastic CP aged 6-15 years and 15 children with normal development. Children with CP were categorized into level I (n =…

  13. To What Extent Is Mean EMG Frequency during Gait a Reflection of Functional Muscle Strength in Children with Cerebral Palsy?

    ERIC Educational Resources Information Center

    Van Gestel, L.; Wambacq, H.; Aertbelien, E.; Meyns, P.; Bruyninckx, H.; Bar-On, L.; Molenaers, G.; De Cock, P.; Desloovere, K.

    2012-01-01

    The aim of the current paper was to analyze the potential of the mean EMG frequency, recorded during 3D gait analysis (3DGA), for the evaluation of functional muscle strength in children with cerebral palsy (CP). As walking velocity is known to also influence EMG frequency, it was investigated to which extent the mean EMG frequency is a reflection…

  14. Effects of 16-week functional movement screen training program on strength and flexibility of elite high school baseball players.

    PubMed

    Song, Hong-Sun; Woo, Seung-Seok; So, Wi-Young; Kim, Kwang-Jun; Lee, Joohyung; Kim, Joo-Young

    2014-04-01

    Functional Movement Screen (FMS) is a way to pretest functional movement. This study examined the effects of the FMS training program on the strength and flexibility of 62 elite male high school baseball players (31 in the training group, 31 in the control group). All players who received less than two points on each FMS test item had to join the 16-week, three times weekly FMS training program. To analyze results among the FMS participants, measures including intraclass correlation coefficient (ICC) and repeated measure ANOVA were utilized. The Kappa coefficient was 0.805 when the intraclass correlation coefficient of the three participants was inspected. Strength showed a significant interaction depending on time and group (hand grip strength: P=0.011, bench press and squat both for one-repetition maximum (1RM): P=0.001 and P=0.008, respectively). Back muscle strength did not show a significant difference (P=0.660). Trunk forward flexion showed no interaction depending on time and groups (P=0.983) but trunk extension backward showed significant differences depending on groups (P=0.004) and time (P=0.001). Splits showed a significant difference depending on time and groups (P=0.004). The FMS training program improved the strength and flexibility of elite high school baseball players.

  15. Effects of 16-week functional movement screen training program on strength and flexibility of elite high school baseball players

    PubMed Central

    Song, Hong-Sun; Woo, Seung-Seok; So, Wi-Young; Kim, Kwang-Jun; Lee, Joohyung; Kim, Joo-Young

    2014-01-01

    Functional Movement Screen (FMS) is a way to pretest functional movement. This study examined the effects of the FMS training program on the strength and flexibility of 62 elite male high school baseball players (31 in the training group, 31 in the control group). All players who received less than two points on each FMS test item had to join the 16-week, three times weekly FMS training program. To analyze results among the FMS participants, measures including intraclass correlation coefficient (ICC) and repeated measure ANOVA were utilized. The Kappa coefficient was 0.805 when the intraclass correlation coefficient of the three participants was inspected. Strength showed a significant interaction depending on time and group (hand grip strength: P=0.011, bench press and squat both for one-repetition maximum (1RM): P=0.001 and P=0.008, respectively). Back muscle strength did not show a significant difference (P=0.660). Trunk forward flexion showed no interaction depending on time and groups (P=0.983) but trunk extension backward showed significant differences depending on groups (P=0.004) and time (P=0.001). Splits showed a significant difference depending on time and groups (P=0.004). The FMS training program improved the strength and flexibility of elite high school baseball players. PMID:24877049

  16. In situ nanomechanical measurements of interfacial strength in membrane-embedded chemically functionalized Si microwires for flexible solar cells.

    PubMed

    Cho, Clara J; O'Leary, Leslie; Lewis, Nathan S; Greer, Julia R

    2012-06-13

    Arrays of vertically aligned Si microwires embedded in polydimethylsiloxane (PDMS) have emerged as a promising candidate for use in solar energy conversion devices. Such structures are lightweight and concurrently demonstrate competitive efficiency and mechanical flexibility. To ensure reliable functioning under bending and flexing, strong interfacial adhesion between the nanowire and the matrix is needed. In situ uniaxial tensile tests of individual, chemically functionalized, Si microwires embedded in a compliant PDMS matrix reveal that chemical functionality on Si microwire surfaces is directly correlated with interfacial adhesion strength. Chemical functionalization can therefore serve as an effective methodology for accessing a wide range of interfacial adhesion between the rigid constituents and the soft polymer matrix; the adhesion can be quantified by measuring the mechanical strength of such systems.

  17. Carboxyl functionalization of carbon fibers via aryl diazonium reaction in molten urea to enhance interfacial shear strength

    NASA Astrophysics Data System (ADS)

    Wang, Yuwei; Meng, Linghui; Fan, Liquan; Wu, Guangshun; Ma, Lichun; Zhao, Min; Huang, Yudong

    2016-01-01

    Using molten urea as the solvent, carbon fibers were functionalized with carboxylic acid groups via aryl diazonium reaction in 15 min to improve their interfacial bonding with epoxy resin. The surface functionalization was quantified by X-ray photoelectron spectroscopy, which showed that the relative surface coverage of carboxylic acid groups increased from an initial percentage of 3.17-10.41%. Mechanical property test results indicated that the aryl diazonium reaction in this paper could improve the interfacial shear strength by 66%. Meanwhile, the technique did not adopt any pre-oxidation step to produce functional groups prior to grafting and was shown to maintain the tensile strength of the fibers. This methodology provided a rapid, facile and economically viable route to produce covalently functionalized carbon fibers in large quantities with an eco-friendly method.

  18. Dietary protein intake is associated with better physical function and muscle strength among elderly women.

    PubMed

    Isanejad, Masoud; Mursu, Jaakko; Sirola, Joonas; Kröger, Heikki; Rikkonen, Toni; Tuppurainen, Marjo; Erkkilä, Arja T

    2016-04-14

    Dietary protein intake might be beneficial to physical function (PF) in the elderly. We examined the cross-sectional and prospective associations of protein intake of g/kg body weight (BW), fat mass (FM) and lean mass (LM) with PF in 554 women aged 65·3-71·6 years belonging to the Osteoporosis Risk Factor and Prevention Fracture Prevention Study. Participants filled a questionnaire on lifestyle factors and 3-d food record in 2002. Body composition was measured by dual-energy X-ray absorptiometry, and PF measures were performed at baseline and at 3-year follow-up. Sarcopaenia was defined using European Working Group on Sarcopenia in Older People criteria. At the baseline, women with higher protein intake (≥ 1·2 g/kg BW) had better performance in hand-grip strength/body mass (GS/BM) (P=0·001), knee extension/BM (P=0·003), one-leg stance (P=0·047), chair rise (P=0·043), squat (P=0·019), squat to the ground (P=0·001), faster walking speed for 10 m (P=0·005) and higher short physical performance battery score (P=0·004) compared with those with moderate and lower intakes (0·81-1·19 and ≤ 0·8 g/kg BW, respectively). In follow-up results, higher protein intake was associated with less decline in GS/BM, one-leg stance and tandem walk for 6 m over 3 years. Overall, results were no longer significant after controlling for FM. Associations were detected between protein intake and PF in non-sarcopaenic women but not in sarcopaenic women, except for change of GS (P=0·037). Further, FM but not LM was negatively associated with PF measures (P<0·050). This study suggests that higher protein intake and lower FM might be positively associated with PF in elderly women.

  19. Enhanced aqueous dissolution of a DNAPL source to characterize the source strength function

    NASA Astrophysics Data System (ADS)

    Wang, Fang; Annable, Michael D.; Schaefer, Charles E.; Ault, Timothy D.; Cho, Jaehyun; Jawitz, James W.

    2014-11-01

    Simplified analytical solutions, developed as source strength functions (SSFs), are capable of describing the temporal dissolution of nonaqueous phase liquids in groundwater, which is useful for predicting source longevity and can serve as a guide for remedial activities. Here, SSF parameters were estimated by fitting enhanced aqueous dissolution data from a flow cell consisting of three injection and four extraction wells to analytical dissolution models (power law model (PLM) and equilibrium streamtube model (EST)) at a trichloroethene (TCE) contaminated site, Alameda Point, California. Both the PLM and the EST model were able to characterize the observed aqueous TCE dissolution during enhanced water flooding. Additional field activities conducted at the site included soil core collection, a recirculated partitioning tracer test, passive flux meter transects, and push-pull tracer tests. The additional site characterization data were used to independently estimate the observed SSF parameters using information such as the TCE mass, distribution and porous media heterogeneity. The exponential decay model (a subset of the PLM) accurately predicted the enhanced dissolution, likely because the site was significantly aged (most of the mass in the plume rather than in the source zone) or middle stage, and the mass in the source zone could be approximately estimated. The EST tracer-based model, when combined with data from the recirculated partitioning tracer test, soil cores, and the push-pull tracer test, was capable of accurately predicting the observed aqueous dissolution. The mass in the source zone and the fraction of contaminated flowpaths were the most important site characteristics, requiring the greatest accuracy to predict aqueous dissolution. Establishing steady state dissolution was essential to provide a more accurate estimate of the fraction contaminated and high resolution data from soil cores in the source zone were needed to estimate the mass present.

  20. Solar cell contact pull strength as a function of pull-test temperature

    NASA Technical Reports Server (NTRS)

    Yasui, R. K.; Berman, P. A.

    1972-01-01

    Four types of solar cell contacts were given pull-strength tests at temperatures between -173 and +165 C. Contacts tested were: (1) solder-coated titanium-silver contacts on n-p cells, (2) palladium-containing titanium-silver contacts on n-p cells, (3) titanium-silver contacts on 0.2-mm-thick n-p cells, and (4) solder-coated electroless-nickel-plated contacts on p-n cells. Maximum pull strength was demonstrated at temperatures significantly below the air mass zero cell equilibrium temperature of +60 C. At the lowest temperatures, the chief failure mechanism was silicon fracture along crystallographic planes; at the highest temperatures, it was loss of solder strength. In the intermediate temperatures, many failure mechanisms operated. Pull-strength tests give a good indication of the suitability of solar cell contact systems for space use. Procedures used to maximize the validity of the results are described.

  1. Blood flow-restricted strength training displays high functional and biological efficacy in women: a within-subject comparison with high-load strength training.

    PubMed

    Ellefsen, Stian; Hammarström, Daniel; Strand, Tor A; Zacharoff, Erika; Whist, Jon E; Rauk, Irene; Nygaard, Håvard; Vegge, Geir; Hanestadhaugen, Marita; Wernbom, Mathias; Cumming, Kristoffer T; Rønning, Roar; Raastad, Truls; Rønnestad, Bent R

    2015-10-01

    Limited data exist on the efficacy of low-load blood flow-restricted strength training (BFR), as compared directly to heavy-load strength training (HST). Here, we show that 12 wk of twice-a-week unilateral BFR [30% of one repetition maximum (1RM) to exhaustion] and HST (6-10RM) of knee extensors provide similar increases in 1RM knee extension and cross-sectional area of distal parts of musculus quadriceps femoris in nine untrained women (age 22 ± 1 yr). The two protocols resulted in similar acute increases in serum levels of human growth hormone. On the cellular level, 12 wk of BFR and HST resulted in similar shifts in muscle fiber composition in musculus vastus lateralis, evident as increased MyHC2A proportions and decreased MyHC2X proportions. They also resulted in similar changes of the expression of 29 genes involved in skeletal muscle function, measured both in a rested state following 12 wk of training and subsequent to singular training sessions. Training had no effect on myonuclei proportions. Of particular interest, 1) gross adaptations to BFR and HST were greater in individuals with higher proportions of type 2 fibers, 2) both BFR and HST resulted in approximately four-fold increases in the expression of the novel exercise-responsive gene Syndecan-4, and 3) BFR provided lesser hypertrophy than HST in the proximal half of musculus quadriceps femoris and also in CSApeak, potentially being a consequence of pressure from the tourniquet utilized to achieve blood flow restriction. In conclusion, BFR and HST of knee extensors resulted in similar adaptations in functional, physiological, and cell biological parameters in untrained women.

  2. Blood flow-restricted strength training displays high functional and biological efficacy in women: a within-subject comparison with high-load strength training

    PubMed Central

    Hammarström, Daniel; Strand, Tor A.; Zacharoff, Erika; Whist, Jon E.; Rauk, Irene; Nygaard, Håvard; Vegge, Geir; Hanestadhaugen, Marita; Wernbom, Mathias; Cumming, Kristoffer T.; Rønning, Roar; Raastad, Truls; Rønnestad, Bent R.

    2015-01-01

    Limited data exist on the efficacy of low-load blood flow-restricted strength training (BFR), as compared directly to heavy-load strength training (HST). Here, we show that 12 wk of twice-a-week unilateral BFR [30% of one repetition maximum (1RM) to exhaustion] and HST (6-10RM) of knee extensors provide similar increases in 1RM knee extension and cross-sectional area of distal parts of musculus quadriceps femoris in nine untrained women (age 22 ± 1 yr). The two protocols resulted in similar acute increases in serum levels of human growth hormone. On the cellular level, 12 wk of BFR and HST resulted in similar shifts in muscle fiber composition in musculus vastus lateralis, evident as increased MyHC2A proportions and decreased MyHC2X proportions. They also resulted in similar changes of the expression of 29 genes involved in skeletal muscle function, measured both in a rested state following 12 wk of training and subsequent to singular training sessions. Training had no effect on myonuclei proportions. Of particular interest, 1) gross adaptations to BFR and HST were greater in individuals with higher proportions of type 2 fibers, 2) both BFR and HST resulted in approximately four-fold increases in the expression of the novel exercise-responsive gene Syndecan-4, and 3) BFR provided lesser hypertrophy than HST in the proximal half of musculus quadriceps femoris and also in CSApeak, potentially being a consequence of pressure from the tourniquet utilized to achieve blood flow restriction. In conclusion, BFR and HST of knee extensors resulted in similar adaptations in functional, physiological, and cell biological parameters in untrained women. PMID:26202071

  3. The Nd150(He3,t) and Sm150(t,He3) reactions with applications to ββ decay of Nd150

    NASA Astrophysics Data System (ADS)

    Guess, C. J.; Adachi, T.; Akimune, H.; Algora, A.; Austin, Sam M.; Bazin, D.; Brown, B. A.; Caesar, C.; Deaven, J. M.; Ejiri, H.; Estevez, E.; Fang, D.; Faessler, A.; Frekers, D.; Fujita, H.; Fujita, Y.; Fujiwara, M.; Grinyer, G. F.; Harakeh, M. N.; Hatanaka, K.; Herlitzius, C.; Hirota, K.; Hitt, G. W.; Ishikawa, D.; Matsubara, H.; Meharchand, R.; Molina, F.; Okamura, H.; Ong, H. J.; Perdikakis, G.; Rodin, V.; Rubio, B.; Shimbara, Y.; Süsoy, G.; Suzuki, T.; Tamii, A.; Thies, J. H.; Tur, C.; Verhanovitz, N.; Yosoi, M.; Yurkon, J.; Zegers, R. G. T.; Zenihiro, J.

    2011-06-01

    The Nd150(He3,t) reaction at 140 MeV/u and Sm150(t,He3) reaction at 115 MeV/u were measured, populating excited states in Pm150. The transitions studied populate intermediate states of importance for the (neutrinoless) ββ decay of Nd150 to Sm150. Monopole and dipole contributions to the measured excitation-energy spectra were extracted by using multipole decomposition analyses. The experimental results were compared with theoretical calculations obtained within the framework of the quasiparticle random-phase approximation, which is one of the main methods employed for estimating the half-life of the neutrinoless ββ decay (0νββ) of Nd150. The present results thus provide useful information on the neutrino responses for evaluating the 0νββ and 2νββ matrix elements. The 2νββ matrix element calculated from the Gamow-Teller transitions through the lowest 1+ state in the intermediate nucleus is maximally about half that deduced from the half-life measured in 2νββ direct counting experiments, and at least several transitions through 1+ intermediate states in Pm150 are required to explain the 2νββ half-life. Because Gamow-Teller transitions in the Sm150(t,He3) experiment are strongly Pauli blocked, the extraction of Gamow-Teller strengths was complicated by the excitation of the 2ℏω, ΔL=0, ΔS=1 isovector spin-flip giant monopole resonance (IVSGMR). However, the near absence of Gamow-Teller transition strength made it possible to cleanly identify this resonance, and the strength observed is consistent with the full exhaustion of the non-energy-weighted sum rule for the IVSGMR.

  4. The {sup 150}Nd({sup 3}He,t) and {sup 150}Sm(t,{sup 3}He) reactions with applications to {beta}{beta} decay of {sup 150}Nd

    SciTech Connect

    Guess, C. J.; Brown, B. A.; Deaven, J. M.; Hitt, G. W.; Meharchand, R.; Zegers, R. G. T.; Adachi, T.; Fujita, H.; Hatanaka, K.; Hirota, K.; Ishikawa, D.; Matsubara, H.; Okamura, H.; Ong, H. J.; Suzuki, T.; Tamii, A.; Yosoi, M.; Zenihiro, J.; Akimune, H.; Algora, A.

    2011-06-15

    The {sup 150}Nd({sup 3}He,t) reaction at 140 MeV/u and {sup 150}Sm(t,{sup 3}He) reaction at 115 MeV/u were measured, populating excited states in {sup 150}Pm. The transitions studied populate intermediate states of importance for the (neutrinoless) {beta}{beta} decay of {sup 150}Nd to {sup 150}Sm. Monopole and dipole contributions to the measured excitation-energy spectra were extracted by using multipole decomposition analyses. The experimental results were compared with theoretical calculations obtained within the framework of the quasiparticle random-phase approximation, which is one of the main methods employed for estimating the half-life of the neutrinoless {beta}{beta} decay (0{nu}{beta}{beta}) of {sup 150}Nd. The present results thus provide useful information on the neutrino responses for evaluating the 0{nu}{beta}{beta} and 2{nu}{beta}{beta} matrix elements. The 2{nu}{beta}{beta} matrix element calculated from the Gamow-Teller transitions through the lowest 1{sup +} state in the intermediate nucleus is maximally about half that deduced from the half-life measured in 2{nu}{beta}{beta} direct counting experiments, and at least several transitions through 1{sup +} intermediate states in {sup 150}Pm are required to explain the 2{nu}{beta}{beta} half-life. Because Gamow-Teller transitions in the {sup 150}Sm(t,{sup 3}He) experiment are strongly Pauli blocked, the extraction of Gamow-Teller strengths was complicated by the excitation of the 2({h_bar}/2{pi}){omega}, {Delta}L=0, {Delta}S=1 isovector spin-flip giant monopole resonance (IVSGMR). However, the near absence of Gamow-Teller transition strength made it possible to cleanly identify this resonance, and the strength observed is consistent with the full exhaustion of the non-energy-weighted sum rule for the IVSGMR.

  5. Beta-Decay Studies near 100Sn

    SciTech Connect

    Karny, M.; Batist, L.; Banu, A.; Becker, F.; Blazhev, A.; Burkard, K.; Bruchle, W.; Doring, J.; Faestermann, T.; Gorska, M.; Grawe, H.; Janas, Z.; Jungclaus, A.; Kavatsyuk, M.; Kavatsyuk, O.; Kirchner, R.; La Commara, M.; Mandal, S.; Mazzocchi, C.; Miernik, K.; Mukha, I.; Muralithar, S.; Plettner, C.; Plochocki, A.; Roeckl, E.; Romoli, M.; Rykaczewski, Krzysztof Piotr; Schadel, M.; Schmidt, K.; Schwengner, R.; Zylicz, J.

    2005-01-01

    The {beta}-decay of {sup 102}Sn was studied by using high-resolution germanium detectors as well as a Total Absorption Spectrometer (TAS). A decay scheme has been constructed based on the {gamma}-{gamma} coincidence data. The total experimental Gamow-Teller strength B{sub GT}{sup exp} of {sup 102}Sn was deduced from the TAS data to be 4.2(9). A search for {beta}-delayed {gamma}-rays of {sup 100}Sn decay remained unsuccessful. However, a Gamow-Teller hindrance factor h = 2.2(3), and a cross-section of about 3nb for the production of {sup 100}Sn in fusion-evaporation reaction between {sup 58}Ni beam and {sup 50}Cr target have been estimated from the data on heavier tin isotopes. The estimated hindrance factor is similar to the values derived for lower shell nuclei.

  6. Ultimate Tensile Strength as a Function of Test Rate for Various Ceramic Matrix Composites at Elevated Temperatures

    NASA Technical Reports Server (NTRS)

    Choi, Sung R.; Bansal, Narottam P.; Gyekenyesi, John P.

    2002-01-01

    Ultimate tensile strength of five different continuous fiber-reinforced ceramic composites, including SiC/BSAS (2D 2 types), SiC/MAS-5 (2D), SiC/SiC (2D enhanced), and C/SiC(2D) was determined as a function of test rate at I 100 to 1200 'C in air. All five composite materials exhibited a significant dependency of ultimate strength on test rate such that the ultimate strength decreased with decreasing test rate, similar to the behavior observed in many advanced monolithic ceramics at elevated temperatures. The application of the preloading technique as well as the prediction of life from one loading configuration (constant stress rate) to another (constant stress loading) for SiC/BSAS suggested that the overall macroscopic failure mechanism of the composites would be the one governed by a power-law type of damage evolution/accumulation, analogous to slow crack growth commonly observed in advanced monolithic ceramics.

  7. Neutron-proton correlations in an exactly solvable model

    SciTech Connect

    Engel, J.; Pittel, S.; Stoitsov, M.; Vogel, P.; Dukelsky, J.

    1997-04-01

    We examine isovector and isoscalar neutron-proton correlations in an exactly solvable model based on the algebra SO(8). We look particularly closely at Gamow-Teller strength and double {beta} decay, both to isolate the effects of the two kinds of pairing and to test two approximation schemes: the renormalized neutron-proton quasiparticle random phase approximation (QRPA) and generalized BCS theory. When isoscalar pairing correlations become strong enough a phase transition occurs and the dependence of the Gamow-Teller {beta}{sup +} strength on isospin changes in a dramatic and unfamiliar way, actually increasing as neutrons are added to an N=Z core. Renormalization eliminates the well-known instabilities that plague the QRPA as the phase transition is approached, but only by unnaturally suppressing the isoscalar correlations. Generalized BCS theory, on the other hand, reproduces the Gamow-Teller strength more accurately in the isoscalar phase than in the usual isovector phase, even though its predictions for energies are equally good everywhere. It also mixes T=0 and T=1 pairing, but only on the isoscalar side of the phase transition. {copyright} {ital 1997} {ital The American Physical Society}

  8. Strength Training Induces Muscle Hypertrophy and Functional Gains in Black Prostate Cancer Patients Despite Androgen Deprivation Therapy

    PubMed Central

    Hurley, Ben F.

    2013-01-01

    Background. Androgen deprivation therapy (ADT) for prostate cancer (PCa) is associated with weakness, fatigue, sarcopenia, and reduced quality of life (QoL). Black men have a higher incidence and mortality from PCa than Caucasians. We hypothesized that despite ADT, strength training (ST) would increase muscle power and size, thereby improving body composition, physical function, fatigue levels, and QoL in older black men with PCa. Methods. Muscle mass, power, strength, endurance, physical function, fatigue perception, and QoL were measured in 17 black men with PCa on ADT before and after 12 weeks of ST. Within-group differences were determined using t tests and regression models. Results. ST significantly increased total body muscle mass (2.7%), thigh muscle volume (6.4%), power (17%), and strength (28%). There were significant increases in functional performance (20%), muscle endurance (110%), and QoL scores (7%) and decreases in fatigue perception (38%). Improved muscle function was associated with higher functional performance (R 2 = 0.54) and lower fatigue perception (R 2 = 0.37), and both were associated with improved QoL (R 2 = 0.45), whereas fatigue perception tended to be associated with muscle endurance (R 2 = 0.37). Conclusions. ST elicits muscle hypertrophy even in the absence of testosterone and is effective in counteracting the adverse functional consequences of ADT in older black men with PCa. These improvements are associated with reduced fatigue perception, enhanced physical performance, and improved QoL. Thus, ST may be a safe and well-tolerated therapy to prevent the loss of muscle mass, strength, and power commonly observed during ADT. PMID:23089339

  9. Large-scale deformed quasiparticle random-phase approximation calculations of the γ -ray strength function using the Gogny force

    NASA Astrophysics Data System (ADS)

    Martini, M.; Péru, S.; Hilaire, S.; Goriely, S.; Lechaftois, F.

    2016-07-01

    Valuable theoretical predictions of nuclear dipole excitations in the whole chart are of great interest for different nuclear applications, including in particular nuclear astrophysics. Here we present large-scale calculations of the E 1 γ -ray strength function obtained in the framework of the axially symmetric deformed quasiparticle random-phase approximation based on the finite-range Gogny force. This approach is applied to even-even nuclei, the strength function for odd nuclei being derived by interpolation. The convergence with respect to the adopted number of harmonic oscillator shells and the cutoff energy introduced in the 2-quasiparticle (2 -q p ) excitation space is analyzed. The calculations performed with two different Gogny interactions, namely D1S and D1M, are compared. A systematic energy shift of the E 1 strength is found for D1M relative to D1S, leading to a lower energy centroid and a smaller energy-weighted sum rule for D1M. When comparing with experimental photoabsorption data, the Gogny-QRPA predictions are found to overestimate the giant dipole energy by typically ˜2 MeV. Despite the microscopic nature of our self-consistent Hartree-Fock-Bogoliubov plus QRPA calculation, some phenomenological corrections need to be included to take into account the effects beyond the standard 2 -q p QRPA excitations and the coupling between the single-particle and low-lying collective phonon degrees of freedom. For this purpose, three prescriptions of folding procedure are considered and adjusted to reproduce experimental photoabsorption data at best. All of them are shown to lead to somewhat similar predictions of the E 1 strength, both at low energies and for exotic neutron-rich nuclei. Predictions of γ -ray strength functions and Maxwellian-averaged neutron capture rates for the whole Sn isotopic chain are also discussed and compared with previous theoretical calculations.

  10. EFFECTS OF RESISTANCE EXERCISES AND COMPLEX DECONGESTIVE THERAPY ON ARM FUNCTION AND MUSCULAR STRENGTH IN BREAST CANCER RELATED LYMPHEDEMA.

    PubMed

    Do, J H; Kim, W; Cho, Y K; Lee, J; Song, E J; Chun, Y M; Jeon, J Y

    2015-12-01

    The incorporation of resistance exercises into the lifestyle of patients with lymphedema is understudied and an emerging interest. We investigated the effectiveness and results of adding a moderate intensity resistance exercise program for 8 weeks in conjunction with intensive CDT for 1 or 2 weeks (depending on severity) on arm volume, arm function, QOL, and muscular strength in patients with breast cancer-related lymphedema. This prospective, pilot trial included forty-four patients with a history of breast cancer who were beginning complex decongestive therapy for lymphedema. They were assigned to either the intervention (n = 22) or control (n = 22). groups. The intervention comprised of resis- tance band exercises 5 times a week for 8 weeks. These were initially supervised during the intensive lymphedema treatment, but performed independently during the study period. Limb volume, muscular strength, and the European Organization for Research and Treatment of Cancer QOL Questionnaire C30 (EORTC QLQ-C30), EORTC-Breast Cancer-Specific QOL Questionnaire (EORTC QLQ-BR23), and Disabilities of Arm, Shoulder, and Hand (DASH) questionnaires were assessed at baseline and at 8 weeks. After 8 weeks, the intervention group demonstrated statistically significant differences (p < 0.05) in the DASH score and muscular strength compared to the control group. Our results indicate that upper body resistance exercise demonstrates a positive effect on arm function and muscular strength without increasing arm volume in breast cancer related lymphedema during and shortly post intensive CDT lymphedema treatment. PMID:27164764

  11. β -delayed γ-decay of 26 P

    NASA Astrophysics Data System (ADS)

    Perez-Loureiro, David; Wrede, C.; Bennett, M. B.; Liddick, S. N.; E10034 Collaboration

    2016-03-01

    The β-decay of proton-rich nuclei is a powerful tool in nuclear science; it can be used to probe quenching of the Gamow-Teller strength, isospin asymmetries, and nuclear astrophysics. 26P β-delayed γ-decay has been recently measured at the National Superconducting Cyclotron Laboratory at MSU with much higher sensitivity than the previous experiment. A fast 26P beam produced using nuclear fragmentation was implanted into a planar germaninum detector. This detector was surrounded by the SeGA germanium array in order to detect the γ rays emitted in coincidence with β-decays with high resolution. Absolute γ-ray intensities were measured and a complete decay scheme was built for the allowed transitions to bound excited states of 26Si. Log ft values and Gamow-Teller strengths were determined for each transition and compared to shell model calculations and the β-decay of its mirror nucleus 26Na. Results of this study, including a larger Gamow-Teller quenching than the sd shell average and a substantial mirror asymmetry between the β+ and β- transitions to the first excited states of 26Si and 26Mg, respectively, will be presented and interpreted. This work is supported by the U.S. NSF under Grants PHY-1102511 and PHY-0822648, the U.S. DOE under contract DE-FG02-97ER41020 and the US NNSA under contract NA0000979.

  12. Study of Photon Strength Function of Actinides: the Case of (235)U, (238)Np and (241)Pu

    SciTech Connect

    Guerrero, C.; Koehler, Paul Edward; N_TOF collaboration,

    2011-01-01

    The decay from excited levels in medium and heavy nuclei can be described in a statistical approach by means of Photon Strength Functions and Level Density distributions. The study of electromagnetic cascades following neutron capture based on the use of high efficiency detectors has been shown to be well suited for probing the properties of the Photon Strength Function of heavy (high level density) and/or radioactive (high background) nuclei. In this work we have investigated for the first time the validity of the recommended PSF of actinides, in particular {sup 235}U, {sup 238}Np and {sup 241}Pu. Our study includes the search for resonance structures in the PSF below Sn and draws conclusions regarding their existence and their characteristics in terms of energy, width and electromagnetic nature.

  13. Relationship between functional movement screen scores, core strength, posture, and body mass index in school children in Moldova.

    PubMed

    Mitchell, Ulrike H; Johnson, A Wayne; Adamson, Brynn

    2015-05-01

    The assessment of functionality should include parameters that consider postural control, limb asymmetries, range of motion limitations, proprioceptive deficits, and pain. An increasingly popular battery of tests, the Functional Movement Screen (FMS), is purported to assess the above named parameters. The purpose of our study was twofold: (a) to report differences in total FMS scores in children, provide preliminary normative reference values of each of the 7 individual FMS scores for both genders and report on asymmetries and (b) to evaluate the relationship between total FMS scores, age, body mass index (BMI), core strength/stability, and postural angles to explore the possibility of using the FMS in the assessment of children's functional fitness. Descriptive data on 77 children aged 8-11 years were collected. The children performed core strength/stability exercises. Photographs were taken from a lateral view for later calculation of postural angles. The children performed the FMS while being videotaped for later review. The average total FMS score (of 21) was 14.9 (+1.9), and BMI was 16.4 (+2.2). Static posture is not related to results of the FMS. Core strength was positively correlated to the total FMS score (r = 0.31; p = 0.006). Over 60% demonstrated at least 1 asymmetry. The individual test scores indicate that none of the test items is too difficult for the children. Based on the screen's correlation to core strength, and the fact that it identifies areas of asymmetry, we suggest to further investigate its possible use in the assessment of children's functional fitness.

  14. Strengthening exercises to improve hand strength and functionality in rheumatoid arthritis with hand deformities: a randomized, controlled trial.

    PubMed

    Cima, Stephanie Robinson; Barone, Adriana; Porto, Jaqueline Mello; de Abreu, Daniela Cristina Carvalho

    2013-03-01

    Rheumatoid arthritis (RA) is a systemic inflammatory and chronic disease of joints, which may result in irreversible deformities. To evaluate the effects of an exercise programme aimed at improving the hand strength in individuals with hand deformities resulting from RA and to analyse the impact these exercises have on functionality. Twenty women with RA hand deformities participated in the study. They were randomly divided into two groups as follows: Group 1 (n = 13) had women participating in the exercise programme aimed at improving handgrip (HS) and pinch strengths (PS) as well as the motor coordination of the hand; Group 2 (n = 7) had women with RA who received no treatment for their hands (control). The treatment programme for hands consisted of 20 sessions, twice a week and at-home exercises. Both groups were submitted to Health Assessment Questionnaire (HAQ) and evaluation of HS and PS by means of dynamometry. Re-evaluations were performed after 10 and 20 sessions in Group 1 and after 2 months in Group 2. After 20 sessions of physiotherapy, Group 1 had a significant gain in HS and PS (p < 0.05) in addition to the improvement of functionality as assessed by HAQ (p = 0.016). For Group 2, no difference was found between the variables analysed (p > 0.05). The strengthening exercises for individuals with RA hand deformity are beneficial to improve handgrip and pinch strengths as well as functionality.

  15. The Effectiveness of Basic Military Training To Improve Functional Lifting Strength in New Recruits.

    PubMed

    Drain, Jace R; Sampson, John A; Billing, Daniel C; Burley, Simon D; Linnane, Denise M; Groeller, Herbert

    2015-11-01

    Australian Army recruits are required to meet the incumbent baseline physical employment standards (PES) during basic military training. A box lift and place (BLP) assessment is included in the PES, and it assesses the ability to perform essential muscular strength tasks. Therefore, basic military training must provide sufficient training stimulus to enable recruits to achieve the baseline BLP standard. A study was undertaken to investigate changes in the performance of 1-repetition maximum BLP in male (n = 154; age, 21.4 years) and female (n = 20; age, 23.1 years) recruits over the first 8 weeks of a 12-week basic military training course. Both male and female recruits showed modest improvements (2.2 ± 5.9 kg and 3.0 ± 3.1 kg, respectively; p ≤ 0.05) in maximal BLP performance, and there were no differences between genders. The female recruits showed greater relative improvements compared with the male recruits (14.7 ± 7.8% vs. 6.5 ± 2.3%). Despite the modest improvements in BLP performance, 70% of female and 100% of male recruits achieved the baseline BLP standard (25 kg) during week 8. The 30% failure rate for female recruits, however, suggests that the basic training program should be improved. A training program that yields greater gains in muscular strength would likely increase female recruit BLP pass rates. Augmented muscular strength would also likely increase the number of recruits capable of achieving higher BLP standards for more physically demanding employment categories. A training program that yields greater improvements in muscular strength may also enable lower entry standards, thereby increasing the recruit pool.

  16. The Effectiveness of Basic Military Training To Improve Functional Lifting Strength in New Recruits.

    PubMed

    Drain, Jace R; Sampson, John A; Billing, Daniel C; Burley, Simon D; Linnane, Denise M; Groeller, Herbert

    2015-11-01

    Australian Army recruits are required to meet the incumbent baseline physical employment standards (PES) during basic military training. A box lift and place (BLP) assessment is included in the PES, and it assesses the ability to perform essential muscular strength tasks. Therefore, basic military training must provide sufficient training stimulus to enable recruits to achieve the baseline BLP standard. A study was undertaken to investigate changes in the performance of 1-repetition maximum BLP in male (n = 154; age, 21.4 years) and female (n = 20; age, 23.1 years) recruits over the first 8 weeks of a 12-week basic military training course. Both male and female recruits showed modest improvements (2.2 ± 5.9 kg and 3.0 ± 3.1 kg, respectively; p ≤ 0.05) in maximal BLP performance, and there were no differences between genders. The female recruits showed greater relative improvements compared with the male recruits (14.7 ± 7.8% vs. 6.5 ± 2.3%). Despite the modest improvements in BLP performance, 70% of female and 100% of male recruits achieved the baseline BLP standard (25 kg) during week 8. The 30% failure rate for female recruits, however, suggests that the basic training program should be improved. A training program that yields greater gains in muscular strength would likely increase female recruit BLP pass rates. Augmented muscular strength would also likely increase the number of recruits capable of achieving higher BLP standards for more physically demanding employment categories. A training program that yields greater improvements in muscular strength may also enable lower entry standards, thereby increasing the recruit pool. PMID:26506184

  17. Tensile strength of thin resin composite layers as a function of layer thickness.

    PubMed

    Alster, D; Feilzer, A J; De Gee, A J; Davidson, C L

    1995-11-01

    As a rule, cast restorations do not allow for free curing contraction of the resin composite luting cement. In a rigid situation, the resulting contraction stress is inversely proportional to the resin layer thickness. Adhesive technology has demonstrated, however, that thin joints may be considerably stronger than thicker ones. To investigate the effects of layer thickness and contraction stress on the tensile strength of resin composite joints, we cured cylindrical samples of a chemically initiated resin composite (Clearfil F2) in restrained conditions and subsequently loaded them in tension. The samples had a diameter of 5.35 mm and thicknesses of 50, 100, 200, 300, 400, 500, 600, and 700 microns, 1.4 mm, or 2.7 mm. None of the samples fractured due to contraction stress prior to tensile loading. Tensile strength decreased gradually from 62 +/- 2 MPa for the 50-microns layer to 31 +/- 4 MPa for the 2.7-mm layer. The failures were exclusively cohesive in resin for layers between 50 and 400 microns thick. Between 500 and 700 microns, the failures were cohesive or mixed adhesive/cohesive, while the 1.4- and 2.7-mm layers always failed in a mixed adhesive/cohesive mode. For the resin composite tested, the contraction stress did not endanger the cohesive strength. It was concluded that if adhesion to tooth structure were improved, thinner adhesive joints might enhance the clinical success of luted restorations.

  18. High-Intensity Strength Training Improves Function of Chronically Painful Muscles: Case-Control and RCT Studies

    PubMed Central

    Andersen, Christoffer H.; Skotte, Jørgen H.; Suetta, Charlotte; Søgaard, Karen; Saltin, Bengt; Sjøgaard, Gisela

    2014-01-01

    Aim. This study investigates consequences of chronic neck pain on muscle function and the rehabilitating effects of contrasting interventions. Methods. Women with trapezius myalgia (MYA, n = 42) and healthy controls (CON, n = 20) participated in a case-control study. Subsequently MYA were randomized to 10 weeks of specific strength training (SST, n = 18), general fitness training (GFT, n = 16), or a reference group without physical training (REF, n = 8). Participants performed tests of 100 consecutive cycles of 2 s isometric maximal voluntary contractions (MVC) of shoulder elevation followed by 2 s relaxation at baseline and 10-week follow-up. Results. In the case-control study, peak force, rate of force development, and rate of force relaxation as well as EMG amplitude were lower in MYA than CON throughout all 100 MVC. Muscle fiber capillarization was not significantly different between MYA and CON. In the intervention study, SST improved all force parameters significantly more than the two other groups, to levels comparable to that of CON. This was seen along with muscle fiber hypertrophy and increased capillarization. Conclusion. Women with trapezius myalgia have lower strength capacity during repetitive MVC of the trapezius muscle than healthy controls. High-intensity strength training effectively improves strength capacity during repetitive MVC of the painful trapezius muscle. PMID:24707475

  19. Verification of the Correlation between Cognitive Function and Lower Limb Muscle Strength for the Community-dwelling Elderly.

    PubMed

    Ohsugi, Hironori; Murata, Shin; Kubo, Atsuko; Hachiya, Mizuki; Hirao, Aya; Fujiwara, Kazuhiko; Kamijou, Kenji

    2014-12-01

    [Purpose] The purpose of this study was to evaluate the lower limb muscle strength of the community-dwelling elderly, with or without cognitive decline, using isometric knee extension strength (IKES) and the 30-second chair stand test (CS-30). [Subjects] A total of 306 community-dwelling elderly participated in this study. Assessment items were the CS-30, IKES, Mini-Mental State Examination (MMSE), and Trail-Making Test Part A (TMT-A). [Methods] Participants were divided into three groups according to their MMSE score: cognitive impairment (MMSE ≤ 24), cognitive decline (MMSE 25 to 27), and normal (MMSE ≥ 28). We compared IKES and CS-30 among the three groups. [Results] IKES was not significantly different among the three groups. However, the CS-30 was significantly different among the three groups. Upon further analysis the CS-30 score of each group, when adjusted for age and TMT-A, did not indicate a significant difference. [Conclusion] These results suggest that the lower limb muscle strength of the elderly does not differ with cognitive decline. Moreover, we suggest that when using the CS-30 score as an indicator of lower limb muscle strength attentional function should be taken into account.

  20. Structure and function of emergency care research networks: strengths, weaknesses, and challenges.

    PubMed

    Papa, Linda; Kuppermann, Nathan; Lamond, Katherine; Barsan, William G; Camargo, Carlos A; Ornato, Joseph P; Stiell, Ian G; Talan, David A

    2009-10-01

    The ability of emergency care research (ECR) to produce meaningful improvements in the outcomes of acutely ill or injured patients depends on the optimal configuration, infrastructure, organization, and support of emergency care research networks (ECRNs). Through the experiences of existing ECRNs, we can learn how to best accomplish this. A meeting was organized in Washington, DC, on May 28, 2008, to discuss the present state and future directions of clinical research networks as they relate to emergency care. Prior to the conference, at the time of online registration, participants responded to a series of preconference questions addressing the relevant issues that would form the basis of the breakout session discussions. During the conference, representatives from a number of existing ECRNs participated in discussions with the attendees and provided a description of their respective networks, infrastructure, and challenges. Breakout sessions provided the opportunity to further discuss the strengths and weaknesses of these networks and patterns of success with respect to their formation, management, funding, best practices, and pitfalls. Discussions centered on identifying characteristics that promote or inhibit successful networks and their interactivity, productivity, and expansion. Here the authors describe the current state of ECRNs and identify the strengths, weaknesses, and potential pitfalls of research networks. The most commonly cited strengths of population- or disease-based research networks identified in the preconference survey were access to larger numbers of patients; involvement of physician experts in the field, contributing to high-level study content; and the collaboration among investigators. The most commonly cited weaknesses were studies with too narrow a focus and restrictive inclusion criteria, a vast organizational structure with a risk of either too much or too little central organization or control, and heterogeneity of institutional

  1. Association of muscle strength, power, and optimal shortening velocity with functional abilities of women with chronic osteoarthritis participating in a multi-modal exercise program.

    PubMed

    Kostka, Joanna S; Czernicki, Jan W; Kostka, Tomasz J

    2014-10-01

    We assessed the relative association of quadriceps muscle strength and power as well as optimal shortening velocity (υ(opt)) to physical functioning in 28 women aged 50-87 years with chronic osteoarthritis participating in a three-week multimodal exercise program. Quadriceps muscle strength, power, υ(opt), and functional performance using the Activities of Daily Living (ADL) scale, Timed Up & Go (TUG) test, Tinetti test, and 6-Minute Walking Test (6-MWT) were assessed pre- and postrehabilitation. With rehabilitation, patients improved the values of strength, power, and the results of all functional tests. Both at baseline and postrehabilitation, functional status was more strongly related to power and υ(opt) than to strength. Functional gains obtained with rehabilitation were not related to changes in power or υ(opt), and only very modestly related to changes in strength. Future studies should assess the benefits and feasibility of power- and velocity-oriented training in patients with osteoarthritis.

  2. Silver oxide-containing hydroxyapatite coating supports osteoblast function and enhances implant anchorage strength in rat femur.

    PubMed

    Eto, Shuichi; Miyamoto, Hiroshi; Shobuike, Takeo; Noda, Iwao; Akiyama, Takayuki; Tsukamoto, Masatsugu; Ueno, Masaya; Someya, Shinsuke; Kawano, Shunsuke; Sonohata, Motoki; Mawatari, Masaaki

    2015-09-01

    Antibacterial silver with hydroxyapatite (Ag-HA) is a promising coating material for imparting antibacterial properties to implants. We previously reported that 3% (w/w) silver with HA (3% Ag-HA) has both antibacterial activity and osteoconductivity. In this study, we investigated the effects of Ag-HA on the in vitro osteoblast function and the in vivo anchorage strength and osteoconductivity of implants. Production of the osteoblast marker alkaline phosphatase, but not cytotoxicity, was observed in cells of the osteoblast cell line MC3T3-E1 cultured on the 3% Ag-HA-coated surface. These results were similar to those observed with silver-free HA coating. In contrast, a significant high level of cytotoxicity was observed when the cells were cultured on a 50% Ag-HA-coated surface. The anchorage strength of implants inserted into the femur of Sprague-Dawley (SD) rats was enhanced by coating the implants with 3% Ag-HA. On the 3% Ag-HA-coated surface, both metaphyseal and diaphyseal areas were largely covered with new bone and had adequate osteoconductivity. These results suggest that 3% Ag-HA, like conventional HA, promotes osteogenesis by supporting osteoblast viability and function and thereby contributes to sufficient anchorage strength of implants. Application of 3% Ag-HA, which combines the osteoconductivity of HA and the antibacterial activity of silver, to prosthetic joints will help prevent postoperative infections. PMID:25808232

  3. Spectroscopy of {sup 13}B via the {sup 13}C(t,{sup 3}He) reaction at 115A MeV

    SciTech Connect

    Guess, C. J.; Zegers, R. G. T.; Brown, B. A.; Deaven, J. M.; Hitt, G. W.; Meharchand, R.; Austin, Sam M.; Perdikakis, G.; Tur, C.; Bazin, D.; Grinyer, G. F.; Caesar, C.; Herlitzius, C.; Noji, S.; Sakai, H.; Shimbara, Y.

    2009-08-15

    Gamow-Teller and dipole transitions to final states in {sup 13}B were studied via the {sup 13}C(t,{sup 3}He) reaction at E{sub t}=115A MeV. In addition to the strong Gamow-Teller transition to the {sup 13}B ground state, a weaker Gamow-Teller transition to a state at 3.6 MeV was found. This state was assigned a spin-parity of 3/2{sup -} by comparison with shell-model calculations using the WBP and WBT interactions which were modified to allow for mixing between n({Dirac_h}/2{pi}){omega} and (n+2)({Dirac_h}/2{pi}){omega} configurations. This assignment agrees with a recent result from a lifetime measurement of excited states in {sup 13}B. The shell-model calculations also explained the relatively large spectroscopic strength measured for a low-lying 1/2{sup +} state at 4.83 MeV in {sup 13}B. The cross sections for dipole transitions up to E{sub x}({sup 13}B)=20 MeV excited via the {sup 13}C(t,{sup 3}He) reaction were also compared with the shell-model calculations. The theoretical cross sections exceeded the data by a factor of about 1.8, which might indicate that the dipole excitations are ''quenched''. Uncertainties in the reaction calculations complicate that interpretation.

  4. Prospective echocardiographic assessment of androgenic-anabolic steroids effects on cardiac structure and function in strength athletes.

    PubMed

    Hartgens, F; Cheriex, E C; Kuipers, H

    2003-07-01

    Since the abuse of androgenic-anabolic steroids (AAS) has been associated with the occurrence of serious cardiovascular disease in young athletes, we performed two studies to investigate the effects of short-term AAS administration on heart structure and function in experienced male strength athletes, with special reference to dose and duration of drug abuse. In Study 1 the effects of AAS were assessed in 17 experienced male strength athletes (age 31 +/- 7 y) who self-administered AAS for 8 or 12 - 16 weeks and in 15 non-using strength athletes (age 33 +/- 5 y) in a non-blinded design. In Study 2 the effects of administration of nandrolone decanoate (200 mg/wk i. m.) for eight weeks were investigated in 16 bodybuilders in a randomised double blind, placebo controlled design. In all subjects M-mode and two-dimensional Doppler-echocardiography were performed at baseline and after 8 weeks AAS administration. In the athletes of Study 1 who used AAS for 12 - 16 weeks a third echocardiogram was also made at the end of the AAS administration period. Echocardiographic examinations included the determination of the aortic diameter (AD), left atrium diameter (LA), left ventricular end diastolic diameter (LVEDD), interventricular septum thickness (IVS), posterior wall end diastolic wall thickness (PWEDWT), left ventricular mass (LVM), left ventricular mass index (LVMI), ejection fraction (EF) and right ventricular diameter (RVD). For assessment of the diastolic function measurements of E and A peak velocities and calculation of E/A ratio were used. In addition, acceleration and deceleration times of the E-top (ATM and DT, respectively) were determined. For evaluation of factors associated with stroke volume the aorta peak flow (AV) and left ventricular ejection times (LVET) were determined. In Study 1 eight weeks AAS self-administration did not result in changes of blood pressure or cardiac size and function. Additionally, duration of AAS self-administration did not have any

  5. Near-infrared line-strengths in elliptical galaxies: evidence for initial mass function variations?

    NASA Astrophysics Data System (ADS)

    Cenarro, A. J.; Gorgas, J.; Vazdekis, A.; Cardiel, N.; Peletier, R. F.

    2003-02-01

    We present new relations between recently defined line-strength indices in the near-infrared (CaT*, CaT, PaT, MgI and sTiO) and central velocity dispersion (σ0) for a sample of 35 early-type galaxies, showing evidence for significant anti-correlations between CaII triplet indices (CaT* and CaT) and log σ0. These relations are interpreted in the light of our recent evolutionary synthesis model predictions, suggesting the existence of important Ca underabundances with respect to Fe and/or an increase of the dwarf to giant stars ratio along the mass sequence of elliptical galaxies.

  6. Gogny-Hartree-Fock-Bogolyubov plus quasiparticle random-phase approximation predictions of the M 1 strength function and its impact on radiative neutron capture cross section

    NASA Astrophysics Data System (ADS)

    Goriely, S.; Hilaire, S.; Péru, S.; Martini, M.; Deloncle, I.; Lechaftois, F.

    2016-10-01

    Valuable theoretical predictions of nuclear dipole excitations in the whole chart are of great interest for different nuclear applications, including in particular nuclear astrophysics. Here we extend our large-scale calculations of the E 1 γ -ray strength function, obtained in the framework of the axially- symmetric-deformed quasiparticle random phase approximation (QRPA) based on the finite-range D1M Gogny force, to the calculation of the M 1 strength function. We compare our QRPA prediction of the M 1 strength with available experimental data and show that a relatively good agreement is obtained provided the strength is shifted globally by about 2 MeV and increased by an empirical factor of 2. Predictions of the M 1 strength function for spherical and deformed nuclei within the valley of β stability as well as in the neutron-rich region are discussed. Its impact on the radiative neutron capture cross section is also analyzed.

  7. Abnormal Resting-State Functional Connectivity Strength in Mild Cognitive Impairment and Its Conversion to Alzheimer's Disease

    PubMed Central

    Li, Yuxia; Wang, Xiaoni; Li, Yongqiu; Sun, Yu; Sheng, Can; Li, Hongyan; Li, Xuanyu; Yu, Yang; Chen, Guanqun; Hu, Xiaochen; Jing, Bin; Wang, Defeng; Li, Kuncheng; Jessen, Frank; Han, Ying

    2016-01-01

    Individuals diagnosed with mild cognitive impairment (MCI) are at high risk of transition to Alzheimer's disease (AD). However, little is known about functional characteristics of the conversion from MCI to AD. Resting-state functional magnetic resonance imaging was performed in 25 AD patients, 31 MCI patients, and 42 well-matched normal controls at baseline. Twenty-one of the 31 MCI patients converted to AD at approximately 24 months of follow-up. Functional connectivity strength (FCS) and seed-based functional connectivity analyses were used to assess the functional differences among the groups. Compared to controls, subjects with MCI and AD showed decreased FCS in the default-mode network and the occipital cortex. Importantly, the FCS of the left angular gyrus and middle occipital gyrus was significantly lower in MCI-converters as compared with MCI-nonconverters. Significantly decreased functional connectivity was found in MCI-converters compared to nonconverters between the left angular gyrus and bilateral inferior parietal lobules, dorsolateral prefrontal and lateral temporal cortices, and the left middle occipital gyrus and right middle occipital gyri. We demonstrated gradual but progressive functional changes during a median 2-year interval in patients converting from MCI to AD, which might serve as early indicators for the dysfunction and progression in the early stage of AD. PMID:26843991

  8. The effects of hand strength on upper extremity function and activities of daily living in stroke patients, with a focus on right hemiplegia

    PubMed Central

    Kim, DeokJu

    2016-01-01

    [Purpose] The purpose of this study was to investigate the effects of hand strength on upper extremity function and activities of daily living in patients with right hemiplegia, as well as to provide important fundamental data for rehabilitation after stroke. [Subjects and Methods] This study was conducted from May 1 to December 30, 2013, at the Department of Rehabilitation of P Hospital in Seoul and included subjects hospitalized with a diagnosis of stroke. Patients with right hemiplegia were selected, and their hand strength, upper extremity function, and activities of daily living were evaluated. Hand strength was measured by grip, lateral pinch, and three-point pinch strength. [Results] The effects of hand strength on upper extremity function were evaluated. The results showed that all types of hand strength significantly influenced upper extremity function. However, only grip strength influenced activities of daily living. [Conclusion] In rehabilitation of stroke patients, it is necessary to first improve their general physical condition and basic activities of daily living, and then improve hand movement and hand muscle strength for instrumental activities of daily living training, which requires detailed hand movements. PMID:27799695

  9. Development, Strength and Functional Evaluation of Plastic Microneedle Array Fabricated by Injection Molding

    NASA Astrophysics Data System (ADS)

    Yoshimura, Chisato; Ishikawa, Hiroyuki; Furuta, Shinji; Aoki, Hikoharu; Sugiyama, Susumu

    We hereby fabricated the microneedle arrays whose dimensions of 300 μm in height, 100 and 150 μm in diagonal lengths of bottom surface and with densities of 900 and 4,400 needles/ cm2 by injection molding. The resist patterns were pre-formed by three-dimensional fine manufacturing with movable resist during the exposure in LIGA process. Polylactic acid was used for microneedle arrays in consideration of the prospective medical use in transdermal methods and the like. Our study was to evaluate the material filling of the needle tips and dermal penetrability. The flexibility of the needle tips was also tested by the force added to the tips, and its result was compared with the analysis of flexibility by CAE; computer aided experiment. The resin filling did not reach to the deepest point of the Ni stamper, and the filling remained within the range of 12 to 17 μm in diameter. However, the penetration rate on pig skin with the density of 900 needles / cm2 resulted in the range of 60 to 80%, and this result represented the satisfactory capability of dermal penetration in spite of the previously described needle tip dimensions of microneedle array. Closely resembling needle flexibility to its analysis proved that CAE analysis on the strength of microstructures was well effective.

  10. An Empirical Investigation of Defense Interpretation Depth, Defensive Functioning, and Alliance Strength in Psychodynamic Psychotherapy.

    PubMed

    Petraglia, Jonathan; Bhatia, Maneet; De Roten, Yves; Despland, Jean-Nicolas; Drapeau, Martin

    2015-01-01

    The present study examined the relationship between depth of defense interpretations by therapists, and patient defensive functioning, on the therapeutic alliance in a sample of 36 patients undergoing short-term dynamic psychotherapy. Defense interpretation depth was defined as the degree to which therapist interpretations contained information regarding the motivation for patient defenses and historical origins of the defensive processes (Greensen, 1967). Mean depth of interpretation was compared between sessions that were identified beforehand as either high-alliance or low-alliance sessions using the Helping Alliance Questionnaire (HAq-II: Luborsky et al., 1996). Results indicated that defensive functioning was correlated to defense interpretation depth in low-alliance sessions. Moreover, mean depth of interpretation was also higher in low-alliance sessions, pointing to the possible "destabilizing" effects that these interpretations may have on both defensive functioning and the therapeutic alliance. These results are discussed within the context of previous studies of therapeutic technique in dynamic psychotherapy.

  11. Acetabular shell deformation as a function of shell stiffness and bone strength.

    PubMed

    Dold, Philipp; Pandorf, Thomas; Flohr, Markus; Preuss, Roman; Bone, Martin C; Joyce, Tom J; Holland, James; Deehan, David

    2016-04-01

    Press-fit acetabular shells used for hip replacement rely upon an interference fit with the bone to provide initial stability. This process may result in deformation of the shell. This study aimed to model shell deformation as a process of shell stiffness and bone strength. A cohort of 32 shells with two different wall thicknesses (3 and 4 mm) and 10 different shell sizes (44- to 62-mm outer diameter) were implanted into eight cadavers. Shell deformation was then measured in the cadavers using a previously validated ATOS Triple Scan III optical system. The shell-bone interface was then considered as a spring system according to Hooke's law and from this the force exerted on the shell by the bone was calculated using a combined stiffness consisting of the measured shell stiffness and a calculated bone stiffness. The median radial stiffness for the 3-mm wall thickness was 4192 N/mm (range, 2920-6257 N/mm), while for the 4-mm wall thickness the median was 9633 N/mm (range, 6875-14,341 N/mm). The median deformation was 48 µm (range, 3-187 µm), while the median force was 256 N (range, 26-916 N). No statistically significant correlation was found between shell stiffness and deformation. Deformation was also found to be not fully symmetric (centres 180° apart), with a median angle discrepancy of 11.5° between the two maximum positive points of deformation. Further work is still required to understand how the bone influences acetabular shell deformation.

  12. Fracture strength and elastic modulus as a function of porosity for hydroxyapatite and other brittle materials, Part II

    SciTech Connect

    Fan, Xiaofeng; Case, Eldon D; Ren, Fei; Shu, Yutian; Baumann, Melissa

    2012-01-01

    Part I of this paper discussed the Weibull modulus m, versus porosity P behavior of brittle materials, including HA. While the Weibull modulus m deals with the scatter in fracture strength data, this paper (Part II) focuses on two additional key mechanical properties of porous materials, namely the average fracture strength f , and Young s modulus E, for P in the interval from P zero to P PG (the porosity of the unfired compacts). The f versus P data for HA from this study and the literature data for alumina, yttria stabilized zirconia (YSZ) and silicon nitride are describedwell by functions of , where = 1 P/PG = the degree of densification. A similar function of applies to the E versus P behavior of HA from this study and data from the literature for alumina, titanium and YSZ. All of the data analyzed in this study (Part II) are based on partially and fully sintered powder compacts (excluding green powder compacts), thus the f / 0 versus and E /E0 versus relationships may apply only to such specimens.

  13. Using anisotropic 3D Minkowski functionals for trabecular bone characterization and biomechanical strength prediction in proximal femur specimens

    NASA Astrophysics Data System (ADS)

    Nagarajan, Mahesh B.; De, Titas; Lochmüller, Eva-Maria; Eckstein, Felix; Wismüller, Axel

    2014-04-01

    The ability of Anisotropic Minkowski Functionals (AMFs) to capture local anisotropy while evaluating topological properties of the underlying gray-level structures has been previously demonstrated. We evaluate the ability of this approach to characterize local structure properties of trabecular bone micro-architecture in ex vivo proximal femur specimens, as visualized on multi-detector CT, for purposes of biomechanical bone strength prediction. To this end, volumetric AMFs were computed locally for each voxel of volumes of interest (VOI) extracted from the femoral head of 146 specimens. The local anisotropy captured by such AMFs was quantified using a fractional anisotropy measure; the magnitude and direction of anisotropy at every pixel was stored in histograms that served as a feature vectors that characterized the VOIs. A linear multi-regression analysis algorithm was used to predict the failure load (FL) from the feature sets; the predicted FL was compared to the true FL determined through biomechanical testing. The prediction performance was measured by the root mean square error (RMSE) for each feature set. The best prediction performance was obtained from the fractional anisotropy histogram of AMF Euler Characteristic (RMSE = 1.01 ± 0.13), which was significantly better than MDCT-derived mean BMD (RMSE = 1.12 ± 0.16, p<0.05). We conclude that such anisotropic Minkowski Functionals can capture valuable information regarding regional trabecular bone quality and contribute to improved bone strength prediction, which is important for improving the clinical assessment of osteoporotic fracture risk.

  14. Strengths and Weaknesses in Executive Functioning in Children with Intellectual Disability

    ERIC Educational Resources Information Center

    Danielsson, Henrik; Henry, Lucy; Messer, David; Ronnberg, Jerker

    2012-01-01

    Children with intellectual disability (ID) were given a comprehensive range of executive functioning measures, which systematically varied in terms of verbal and non-verbal demands. Their performance was compared to the performance of groups matched on mental age (MA) and chronological age (CA), respectively. Twenty-two children were included in…

  15. Topology of Protein Interaction Network Shapes Protein Abundances and Strengths of Their Functional and Nonspecific Interactions

    SciTech Connect

    Maslov, S.; Heo, M.; Shakhnovich, E.

    2011-03-08

    How do living cells achieve sufficient abundances of functional protein complexes while minimizing promiscuous nonfunctional interactions? Here we study this problem using a first-principle model of the cell whose phenotypic traits are directly determined from its genome through biophysical properties of protein structures and binding interactions in a crowded cellular environment. The model cell includes three independent prototypical pathways, whose topologies of protein-protein interaction (PPI) subnetworks are different, but whose contributions to the cell fitness are equal. Model cells evolve through genotypic mutations and phenotypic protein copy number variations. We found a strong relationship between evolved physical-chemical properties of protein interactions and their abundances due to a 'frustration' effect: Strengthening of functional interactions brings about hydrophobic interfaces, which make proteins prone to promiscuous binding. The balancing act is achieved by lowering concentrations of hub proteins while raising solubilities and abundances of functional monomers. On the basis of these principles we generated and analyzed a possible realization of the proteome-wide PPI network in yeast. In this simulation we found that high-throughput affinity capture-mass spectroscopy experiments can detect functional interactions with high fidelity only for high-abundance proteins while missing most interactions for low-abundance proteins.

  16. Trade-off between the Mechanical Strength and Microwave Electrical Properties of Functionalized and Irradiated Carbon Nanotube Sheets.

    PubMed

    Williams, Tiffany S; Orloff, Nathan D; Baker, James S; Miller, Sandi G; Natarajan, Bharath; Obrzut, Jan; McCorkle, Linda S; Lebron-Colón, Marisabel; Gaier, James; Meador, Michael A; Liddle, J Alexander

    2016-04-13

    Carbon nanotube (CNT) sheets represent a novel implementation of CNTs that enable the tailoring of electrical and mechanical properties for applications in the automotive and aerospace industries. Small molecule functionalization and postprocessing techniques, such as irradiation with high-energy particles, are methods that can enhance the mechanical properties of CNTs. However, the effect that these modifications have on the electrical conduction mechanisms has not been extensively explored. By characterizing the mechanical and electrical properties of multiwalled carbon nanotube (MWCNT) sheets with different functional groups and irradiation doses, we can expand our insights into the extent of the trade-off that exists between mechanical strength and electrical conductivity for commercially available CNT sheets. Such insights allow for the optimization of design pathways for engineering applications that require a balance of material property enhancements. PMID:27044063

  17. The strength of EPR and ENDOR techniques in revealing structure-function relationships in metalloproteins.

    PubMed

    Van Doorslaer, Sabine; Vinck, Evi

    2007-09-01

    Recent technological and methodological advances have strongly increased the potential of electron paramagnetic resonance (EPR) and electron nuclear double resonance (ENDOR) techniques to characterize the structure and dynamics of metalloproteins. These developments include the introduction of powerful pulsed EPR/ENDOR methodologies and the development of spectrometers operating at very high microwave frequencies and high magnetic fields. This overview focuses on how valuable information about metalloprotein structure-function relations can be obtained using a combination of EPR and ENDOR techniques. After an overview of the historical development and a limited theoretical description of some of the key EPR and ENDOR techniques, their potential will be highlighted using selected examples of applications to iron-, nickel-, cobalt-, and copper-containing proteins. We will end with an outlook of future developments.

  18. Effect of simultaneous application of postural techniques and expiratory muscle strength training on the enhancement of the swallowing function of patients with dysphagia caused by parkinson's disease.

    PubMed

    Byeon, Haewon

    2016-06-01

    [Purpose] This study aimed to investigate the effect of simultaneous application of postural techniques and expiratory muscle strength training on the enhancement of the swallowing function of patients with dysphagia caused by Parkinson's disease. [Subjects and Methods] The subjects of this study were 18 patients who received simultaneous application of postural techniques and expiratory muscle strength training and 15 patients who received expiratory muscle strength training only. Postural techniques were conducted in the order of chin tucking, head rotation, head tilting, bending head back, and lying down, while expiratory muscle strength training was conducted at a resistance level of about 70% of the maximal expiratory pressure. Swallowing recovery was assessed by using the Functional Dysphagia Scale based on videofluoroscopic studies. [Results] The mean value obtained in the videofluoroscopic studies for both groups decreased after the treatment. In the postural techniques plus expiratory muscle strength training group, the decrease was significantly greater than that in the expiratory muscle strength training-only group. [Conclusion] The results imply that simultaneous performance of postural techniques and expiratory muscle strength training is more effective than expiratory muscle strength training alone when applied in the swallowing rehabilitation for patients with dysphagia caused by Parkinson's disease.

  19. Reproducibility of laser Doppler fluximetry and the process of iontophoresis in assessing microvascular endothelial function using low current strength.

    PubMed

    Al-Tahami, B A; Yvonne-Tee, G B; Halim, A S; Ismail, A A; Rasool, A H G

    2010-04-01

    Iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNP) combined with laser Doppler fluximetry (LDF) is a tool used to determine microvascular endothelial function. Our aim was to study the reproducibility of different parameters of this technique using iontophoresis with low current strength on the forearm skin of healthy subjects. Baseline skin perfusion was done before application of five current pulses with 1 min of current-free interval. Current strength of 0.007 mA, current density of 0.01 mA/cm(2) and charge density of 6 mC/cm(2) were used, along with 1% ACh and 1% SNP. The absolute maximum change in perfusion (max), percent change in perfusion (% change), peak change in perfusion (peak) and area under the curve during iontophoresis (AUC) at the anodal and cathodal leads were recorded. Measurements were performed in three sessions for 2 days. The coefficient of variation (CV) was calculated for each parameter. Among the parameters studied, maximum change in perfusion and peak flux were the most reproducible parameters.

  20. Functional Capacity, Respiratory Muscle Strength, and Oxygen Consumption Predict Mortality in Patients with Cirrhosis

    PubMed Central

    Telles da Rosa, Luis Henrique; Garcia, Eduardo; Marroni, Cláudio Augusto

    2016-01-01

    Introduction. Liver diseases influence musculoskeletal functions and may negatively affect the exercise capacity of patients with cirrhosis. Aim. To test the relationship between the six-minute walk test (6MWT), maximal inspiratory pressure (MIP), and exercise capacity (VO2peak) measures and the survival rate of patients with cirrhosis. Methods. This prospective cohort study consisted of 86 patients diagnosed with cirrhosis with the following aetiology: hepatitis C virus (HCV), hepatitis B virus (HBV), and/or alcoholic cirrhosis (AC). All patients were followed up for three years and submitted to the 6MWT, pressure measurements with a compound gauge, and an exercise test (VO2peak). Results. The survival analysis showed that the individuals who covered a distance shorter than 410 m during the 6MWT had a survival rate of 55% compared with a rate of 97% for the individuals who walked more than 410 m (p = 0.0001). Individuals with MIPs below −70 cmH2O had a survival rate of 62% compared with a rate of 93% for those with MIPs above −70 cmH2O (p = 0.0001). The patients with values below 17 mL/kg had a survival rate of 55% compared with a rate of 94% for those with values above 17 mL/kg (p = 0.0001). Conclusion. The 6MWT distance, MIP, and oxygen consumption are predictors of mortality in patients with cirrhosis. PMID:27559536

  1. Functional Capacity, Respiratory Muscle Strength, and Oxygen Consumption Predict Mortality in Patients with Cirrhosis.

    PubMed

    Faustini Pereira, José Leonardo; Galant, Lucas Homercher; Rossi, Danusa; Telles da Rosa, Luis Henrique; Garcia, Eduardo; de Mello Brandão, Ajácio Bandeira; Marroni, Cláudio Augusto

    2016-01-01

    Introduction. Liver diseases influence musculoskeletal functions and may negatively affect the exercise capacity of patients with cirrhosis. Aim. To test the relationship between the six-minute walk test (6MWT), maximal inspiratory pressure (MIP), and exercise capacity (VO2peak) measures and the survival rate of patients with cirrhosis. Methods. This prospective cohort study consisted of 86 patients diagnosed with cirrhosis with the following aetiology: hepatitis C virus (HCV), hepatitis B virus (HBV), and/or alcoholic cirrhosis (AC). All patients were followed up for three years and submitted to the 6MWT, pressure measurements with a compound gauge, and an exercise test (VO2peak). Results. The survival analysis showed that the individuals who covered a distance shorter than 410 m during the 6MWT had a survival rate of 55% compared with a rate of 97% for the individuals who walked more than 410 m (p = 0.0001). Individuals with MIPs below -70 cmH2O had a survival rate of 62% compared with a rate of 93% for those with MIPs above -70 cmH2O (p = 0.0001). The patients with values below 17 mL/kg had a survival rate of 55% compared with a rate of 94% for those with values above 17 mL/kg (p = 0.0001). Conclusion. The 6MWT distance, MIP, and oxygen consumption are predictors of mortality in patients with cirrhosis. PMID:27559536

  2. Assessment of time-dependent density functional schemes for computing the oscillator strengths of benzene, phenol, aniline, and fluorobenzene

    NASA Astrophysics Data System (ADS)

    Miura, Masanori; Aoki, Yuriko; Champagne, Benoît

    2007-08-01

    In present study the relevance of using the time-dependent density functional theory (DFT) within the adiabatic approximation for computing oscillator strengths (f) is assessed using different LDA, GGA, and hybrid exchange-correlation (XC) functionals. In particular, we focus on the lowest-energy valence excitations, dominating the UV/visible absorption spectra and originating from benzenelike HOMO (π)→LUMO(π*) transitions, of several aromatic molecules: benzene, phenol, aniline, and fluorobenzene. The TDDFT values are compared to both experimental results obtained from gas phase measurements and to results determined using several ab initio schemes: random phase approximation (RPA), configuration interaction single (CIS), and a series of linear response coupled-cluster calculations, CCS, CC2, and CCSD. In particular, the effect of the amount of Hartree-Fock (HF) exchange in the functional is highlighted, whereas a basis set investigation demonstrates the need of including diffuse functions. So, the hybrid XC functionals—and particularly BHandHLYP—provide f values in good agreement with the highly correlated CCSD scheme while these can be strongly underestimated using pure DFT functionals. These results also display systematic behaviors: (i) larger f and squares of the transition dipole moments (∣μ∣2) are associated with larger excitation energies (ΔE); (ii) these relationships present generally a linear character with R >0.9 in least-squares fit procedures; (iii) larger amounts of HF exchange in the XC functional lead to larger f, ∣μ∣2, as well as ΔE values; (iv) these increases in f, ∣μ ∣2, and ΔE are related to increased HOMO-LUMO character; and (v) these relationships are, however, not universal since the linear regression parameters (the slopes and the intercepts at the origin) depend on the system under investigation as well as on the nature of the excited state.

  3. An in vitro method to manipulate the direction and functional strength between neural populations

    PubMed Central

    Pan, Liangbin; Alagapan, Sankaraleengam; Franca, Eric; Leondopulos, Stathis S.; DeMarse, Thomas B.; Brewer, Gregory J.; Wheeler, Bruce C.

    2015-01-01

    We report the design and application of a Micro Electro Mechanical Systems (MEMs) device that permits investigators to create arbitrary network topologies. With this device investigators can manipulate the degree of functional connectivity among distinct neural populations by systematically altering their geometric connectivity in vitro. Each polydimethylsilxane (PDMS) device was cast from molds and consisted of two wells each containing a small neural population of dissociated rat cortical neurons. Wells were separated by a series of parallel micrometer scale tunnels that permitted passage of axonal processes but not somata; with the device placed over an 8 × 8 microelectrode array, action potentials from somata in wells and axons in microtunnels can be recorded and stimulated. In our earlier report we showed that a one week delay in plating of neurons from one well to the other led to a filling and blocking of the microtunnels by axons from the older well resulting in strong directionality (older to younger) of both axon action potentials in tunnels and longer duration and more slowly propagating bursts of action potentials between wells. Here we show that changing the number of tunnels, and hence the number of axons, connecting the two wells leads to changes in connectivity and propagation of bursting activity. More specifically, the greater the number of tunnels the stronger the connectivity, the greater the probability of bursting propagating between wells, and shorter peak-to-peak delays between bursts and time to first spike measured in the opposing well. We estimate that a minimum of 100 axons are needed to reliably initiate a burst in the opposing well. This device provides a tool for researchers interested in understanding network dynamics who will profit from having the ability to design both the degree and directionality connectivity among multiple small neural populations. PMID:26236198

  4. Toe Flexor Strength, Flexibility and Function and Flexor Hallucis Longus Tendon Morphology in Dancers and Non-Dancers.

    PubMed

    Rowley, K Michael; Jarvis, Danielle N; Kurihara, Toshiyuki; Chang, Yu-Jen; Fietzer, Abbigail L; Kulig, Kornelia

    2015-09-01

    Tendinopathy of the flexor hallucis longus (FHL), colloquially referred to as "dancer's tendinitis," is a common condition in dancers and attributed to high demand on this muscle in positions of extreme ankle plantarflexion and metatarsophalangeal (MTP)) flexion and extension. Despite such a high prevalence, there has been little research into preventative or nonsurgical interventions. As a means to identify potential targets for prevention and intervention, this study aimed to characterize toe flexors in dancers by measuring strength, flexibility, function, and FHL tendon morphology. Dancers (n=25) were compared to non-dancers (n=25) in toe flexor isometric strength, first MTP joint range of motion, foot longitudinal arch flexibility, balance ability, endurance during modified heel raises without use of the toes, and FHL tendon thickness, cross-sectional area, and peak spatial frequency. Significant differences were found in functional first MTP joint extension (dancers 101.95°, non-dancers 91.15°, p<0.001), balance ability during single-leg stance on the toes (dancers 11.43 s, non-dancers 5.90 s, p=0.013), and during modified heel raises (dancers 22.20 reps, non-dancers 28.80 reps, p=0.001). Findings indicate that dancers rely on toe flexors more than non-dancers to complete balance and heel raise tasks. Efficacy of using this modified heel raise task with the toes off the edge of a block as a means to train larger plantarflexors and as a nonsurgical intervention should be studied in the future. Improving interventions for FHL tendinopathy will be impactful for dancers, in whom this condition is highly prevalent.

  5. A third L-proline permease in Salmonella typhimurium which functions in media of elevated osmotic strength.

    PubMed Central

    Csonka, L N

    1982-01-01

    Exogenous proline specifically stimulates the growth rate of enteric bacteria in media of inhibitory osmotic strength (J. H. B. Christian, Aust. J. Biol. Sci. 8:490-497, 1955). I observed that Salmonella typhimurium mutants which lack both of the previously known proline permeases (putP proP) are stimulated by proline in media of inhibitory osmolarity. I propose that there is a third proline permease which functions only in media of elevated osmolarity. This conclusion is based on the observations that, in media of elevated osmolarity, (i) the sensitivity of putP proP mutants to toxic proline analogs increases, (ii) proline requirements for maximal growth of proline auxotrophic putP proP mutants decreases, and (iii) the specific rate of incorporation of radioactive proline into protein of growing cells increases. I obtained a Tn10-induced mutation in a gene (proU) required for the functioning of the third proline permease and determined the map location to be at 59 map units of the chromosome, between srlA and tct, 66% linked to nalB in P22 transduction. My results suggest that the function of the third, osmotically stimulated permease might be to accumulate high intracellular proline levels during osmotic stress. Possible mechanisms by which proline might cause growth stimulation are discussed. PMID:7050090

  6. Reduction in Torsional Stiffness and Strength at the Proximal Tibia as a Function of Time Since Spinal Cord Injury.

    PubMed

    Edwards, W Brent; Simonian, Narina; Troy, Karen L; Schnitzer, Thomas J

    2015-08-01

    Spinal cord injury (SCI) is characterized by marked bone loss and a high rate of low-energy fracture around regions of the knee. Changes in the mechanical integrity of bone after SCI are poorly defined, and a better understanding may inform approaches to prevent fractures. The purpose of this study was to quantify reductions in torsional stiffness and strength at the proximal tibia as a function of time since SCI. Sixty adults with SCI ranging from 0 to 50 years of duration and a reference group of 10 able-bodied controls received a CT scan of the proximal tibia. Measures of integral bone mineral were calculated for the total proximal tibia, and localized measures of cortical and trabecular bone mineral were calculated for the epiphysis, metaphysis, and diaphysis. Torsional stiffness (K) and strength (T(ult)) for the total proximal tibia were quantified using validated subject-specific finite element models. Total proximal tibia measures of integral bone mineral, K, and T(ult) decreased exponentially (r(2)  = 0.52 to 0.70) and reached a new steady state within 2.1 to 2.7 years after SCI. Whereas new steady-state values for integral bone mineral and K were 52% to 56% (p < 0.001) lower than the reference group, the new steady state for T(ult) was 69% (p < 0.001) lower than the reference group. Reductions in total proximal tibia measures occurred through a combination of trabecular and endocortical resorption, leaving a bone comprised primarily of marrow fat rather than hydroxyapatite. These findings illustrate that a short therapeutic window exists early (ie, 2 years) after SCI, during which bone-specific intervention may attenuate reductions in mechanical integrity and ultimately prevent SCI-related fragility fracture. PMID:25656743

  7. Effects of Kinesio Tape application to quadriceps muscles on isokinetic muscle strength, gait, and functional parameters in patients with stroke.

    PubMed

    Ekiz, Timur; Aslan, Meryem Doğan; Özgirgin, Neşe

    2015-01-01

    The aim of this study was to evaluate the effects of Kinesio Tape (KT) application to quadriceps muscles on isokinetic muscle strength, gait, and functional parameters in patients with stroke. Twenty-four patients were allocated into KT and control groups. All patients participated in the same conventional rehabilitation program 5 times/wk for 4 wk. In addition, KT was applied to quadriceps muscles bilaterally to the patients in the KT group. Compared with baseline, peak torque levels increased significantly in both groups (all p < 0.05). However, change levels were significantly higher in the KT group than the control group at 60 degrees/second angular velocity (AV) in extension (p = 0.04) and 60 and 180 degrees/second AV in flexion (both p = 0.02) on the paretic side. Moreover, the change levels were more prominent in the KT group at 60 and 180 degrees/second AV in extension (p = 0.03 and p = 0.04, respectively) on the nonparetic side. Gait, balance, mobility, and quality of life values improved significantly in both groups (all p < 0.05), yet the change levels between the groups did not reach significance (p > 0.05). KT application to quadriceps muscles in addition to conventional exercises for 4 wk is effective on isokinetic but not functional parameters.

  8. Effect of Tai-chi exercise on lower limb muscle strength, bone mineral density and balance function of elderly women

    PubMed Central

    Song, Qing-Hua; Zhang, Quan-Hai; Xu, Rong-Mei; Ma, Ming; Zhao, Xin-Ping; Shen, Guo-Qing; Guo, Yan-Hua; Wang, Yi

    2014-01-01

    Abstract: To study the effect of Tai-chi exercise on lower limb muscle strength, bone mineral density and balance function of elderly female, 105 urban elderly women, who do insufficient exercise in daily life, are selected as the subject and randomly divided into an observation group (Tai Chi Group), a control group I (Dance Group) and a control group II (Walking Group). Each group is consists of 35 women. Among them, the women in the observation group do Tai-chi exercise once a day, while the women in the control group I dance once a day and in the control group II stick to brisk walking once a day. All women in the three groups do the above said exercises for 40 minutes and the exercise intensity is controlled to be medium. At the time of selection and after 4, 8 and 12 months upon their exercises, respectively detect and compare the lower limb skeletal muscle mass, lower limb muscle strength, bone mineral density and balance function of the subject. Results: At the time of selection, the general information of the subjects in the three groups show no significant difference (P > 0.05); however, after 4 months’ exercise, most of the study indexes in the control group I and group II are improved significantly (P < 0.05), while most of the study indexes in the observation group show no significant difference (P > 0.05) in comparison with those at the time of selection and their general improvement effect is slightly lower than that in the control group; after 8 months, relevant study indexes of the subjects in the three groups are significantly improved (P < 0.05) in comparison with those at the time of selection, especially, the effect in the observation group is more obvious and is better than that of the control group II (P < 0.05). 12 months later, the effect of the observation group is improved significantly from day to day when comparing to theose in the control group I and group II (P < 0.05 or P < 0.01). Conclusion: Compared with the senile dance and

  9. A comparison of respiratory and peripheral muscle strength, functional exercise capacity, activities of daily living and physical fitness in patients with cystic fibrosis and healthy subjects.

    PubMed

    Arikan, Hulya; Yatar, İlker; Calik-Kutukcu, Ebru; Aribas, Zeynep; Saglam, Melda; Vardar-Yagli, Naciye; Savci, Sema; Inal-Ince, Deniz; Ozcelik, Ugur; Kiper, Nural

    2015-01-01

    There are limited reports that compare muscle strength, functional exercise capacity, activities of daily living (ADL) and parameters of physical fitness of cystic fibrosis (CF) patients with healthy peers in the literature. The purpose of this study was to assess and compare respiratory and peripheral muscle strength, functional exercise capacity, ADL and physical fitness in patients with CF and healthy subjects. Nineteen patients with CF (mean forced expiratory volume in one second-FEV1: 86.56±18.36%) and 20 healthy subjects were included in this study. Respiratory (maximal inspiratory pressure-MIP and maximal expiratory pressure-MEP) and peripheral muscle strength (quadriceps, shoulder abductors and hand grip strength) were evaluated. Functional exercise capacity was determined with 6min walk test (6MWT). ADL was assessed with Glittre ADL test and physical fitness was assessed with Munich fitness test (MFT). There were not any statistically significant difference in MIP, %MIP, MEP and %MEP values between two groups (p>0.05). %Peripheral muscle strength (% quadriceps and shoulder abductors strength), 6MWT distance and %6MWT distance were significantly lower in patients with CF than those of healthy subjects (p<0.05). Glittre ADL-test time was significantly longer in patients with CF than healthy subjects (p<0.05). According to Munich fitness test, the number of bouncing a ball, hanging score, distance of standing vertical jumping and standing vertical jumping score were significantly lower in patients with CF than those of healthy subjects (p<0.05). Peripheral muscle strength, functional exercise capacity, ADL performance and speed, coordination, endurance and power components of physical fitness are adversely affected in mild-severe patients with CF compared to healthy peers. Evaluations must be done in comprehensive manner in patients with CF with all stages. PMID:26241869

  10. A comparison of respiratory and peripheral muscle strength, functional exercise capacity, activities of daily living and physical fitness in patients with cystic fibrosis and healthy subjects.

    PubMed

    Arikan, Hulya; Yatar, İlker; Calik-Kutukcu, Ebru; Aribas, Zeynep; Saglam, Melda; Vardar-Yagli, Naciye; Savci, Sema; Inal-Ince, Deniz; Ozcelik, Ugur; Kiper, Nural

    2015-01-01

    There are limited reports that compare muscle strength, functional exercise capacity, activities of daily living (ADL) and parameters of physical fitness of cystic fibrosis (CF) patients with healthy peers in the literature. The purpose of this study was to assess and compare respiratory and peripheral muscle strength, functional exercise capacity, ADL and physical fitness in patients with CF and healthy subjects. Nineteen patients with CF (mean forced expiratory volume in one second-FEV1: 86.56±18.36%) and 20 healthy subjects were included in this study. Respiratory (maximal inspiratory pressure-MIP and maximal expiratory pressure-MEP) and peripheral muscle strength (quadriceps, shoulder abductors and hand grip strength) were evaluated. Functional exercise capacity was determined with 6min walk test (6MWT). ADL was assessed with Glittre ADL test and physical fitness was assessed with Munich fitness test (MFT). There were not any statistically significant difference in MIP, %MIP, MEP and %MEP values between two groups (p>0.05). %Peripheral muscle strength (% quadriceps and shoulder abductors strength), 6MWT distance and %6MWT distance were significantly lower in patients with CF than those of healthy subjects (p<0.05). Glittre ADL-test time was significantly longer in patients with CF than healthy subjects (p<0.05). According to Munich fitness test, the number of bouncing a ball, hanging score, distance of standing vertical jumping and standing vertical jumping score were significantly lower in patients with CF than those of healthy subjects (p<0.05). Peripheral muscle strength, functional exercise capacity, ADL performance and speed, coordination, endurance and power components of physical fitness are adversely affected in mild-severe patients with CF compared to healthy peers. Evaluations must be done in comprehensive manner in patients with CF with all stages.

  11. [Physical activity can influence the course of early arthritis. Both strength training and aerobic exercise provide pain relief and functional improvement].

    PubMed

    Roos, Ewa

    2002-11-01

    There is no causal treatment for osteoarthritis. Instead treatment is aimed at decreasing pain and improving function. The base of osteoarthritis treatment is education and exercise. Exercise, both aerobic exercise and muscular strength training, have positive effects on pain and function. The minimum recommendations of exercise are equivalent to the recommendations of physical activity to obtain or maintain a good general health. Acupuncture is a safe and effective treatment for osteoarthritis pain. However, function is not automatically improved when pain is relieved.

  12. Fracture strength and elastic modulus as a function of porosity for hydroxyapatite and other brittle materials Part I

    SciTech Connect

    Fan, Xiaofeng; Case, Eldon D; Ren, Fei; Shu, Yutian; Baumann, Melissa

    2012-01-01

    Porous brittle materials are used as filters, catalyst supports, solid oxide fuel cells and biomedical materials. However the literature on the Weibull modulus, m, versus volume fraction porosity, P, is extremely limited despite the importance of m as a gauge of mechanical reliability. In Part I of this study, m is determined for 441 sintered hydroxyapatite (HA) specimens fractured in biaxial flexure for 0.08 P 0.62. In this study, we analyze a combined data set collected from the literature that represents work from a total of 17 different research groups (including the present authors), eight different materials and more than 1560 oxide and non-oxide specimens, the m versus P plot is Ushaped with a wide band of m values for P < 0.1 (Region I) and P > 0.55 (Region III), and a narrower band of m values in the intermediate porosity region of 0.1 < P < 0.55 (Region II). The limited range of m ( 4 < m < 11) in Region II has important implications since Region II includes the P range for the majority of the applications of porous brittle materials. Part II of this study focuses on the P dependence of the mean fracture strength,< f >, and the Young s modulus E for the HA specimens tested in Part I along with literature data for other brittle materials. Both < f > and E are power law functions of the degree of densification, , where = 1 P/PG and PG is the green (unfired) porosity.

  13. Effects of therapeutic ultrasound and exercise on pain, function, and isokinetic shoulder rotator strength of patients with rotator cuff disease

    PubMed Central

    Analan, Pınar Doruk; Leblebici, Berrin; Adam, Mehmet

    2015-01-01

    [Purpose] The aim of this prospective, double-blind, randomized, placebo-controlled study was to evaluate the effects of therapeutic continuous ultrasound (US) on patients with rotator cuff disease. [Subjects and Methods] Twenty-two patients were treated with a standard physiotherapy program consisting of a hot-pack, transcutaneous electrical nerve stimulation (TENS), exercises, and US that was supervised by the same physiotherapist. The patients were randomly assigned to either a group that received true US (n=11) or one that received sham US (n=11). [Results] There were significant differences between the pre- and post-intervention UCLA Shoulder Rating Scale and Constant-Murley Shoulder Outcome scores, VAS, and external rotation (ER) peak torque 60°/second values for both the true and sham US groups. However, the between-group differences were not statistically significant. [Conclusion] In patients with rotator cuff disease, physiotherapy interventions effectively treat the pain, improve the clinical status, and increase the muscle strength of the shoulder ER at a low constant angular velocity, with functional improvement being seen immediately after treatment. However, at the end of the intervention, the US had yielded no additional efficacy to the physiotherapy treatment regimen of the patients with rotator cuff disease. PMID:26644656

  14. Effects of therapeutic ultrasound and exercise on pain, function, and isokinetic shoulder rotator strength of patients with rotator cuff disease.

    PubMed

    Analan, Pınar Doruk; Leblebici, Berrin; Adam, Mehmet

    2015-10-01

    [Purpose] The aim of this prospective, double-blind, randomized, placebo-controlled study was to evaluate the effects of therapeutic continuous ultrasound (US) on patients with rotator cuff disease. [Subjects and Methods] Twenty-two patients were treated with a standard physiotherapy program consisting of a hot-pack, transcutaneous electrical nerve stimulation (TENS), exercises, and US that was supervised by the same physiotherapist. The patients were randomly assigned to either a group that received true US (n=11) or one that received sham US (n=11). [Results] There were significant differences between the pre- and post-intervention UCLA Shoulder Rating Scale and Constant-Murley Shoulder Outcome scores, VAS, and external rotation (ER) peak torque 60°/second values for both the true and sham US groups. However, the between-group differences were not statistically significant. [Conclusion] In patients with rotator cuff disease, physiotherapy interventions effectively treat the pain, improve the clinical status, and increase the muscle strength of the shoulder ER at a low constant angular velocity, with functional improvement being seen immediately after treatment. However, at the end of the intervention, the US had yielded no additional efficacy to the physiotherapy treatment regimen of the patients with rotator cuff disease. PMID:26644656

  15. Effects of high volume upper extremity plyometric training on throwing velocity and functional strength ratios of the shoulder rotators in collegiate baseball players.

    PubMed

    Carter, Andrew B; Kaminski, Thomas W; Douex, Al T; Knight, Christopher A; Richards, James G

    2007-02-01

    To achieve maximal force output, clinicians and coaches have been experimenting with upper extremity plyometric exercises for years, without sufficient scientific validation of this training method. The goal of this study was to examine the effects of an 8-week course of high volume upper extremity plyometric training on the isokinetic strength and throwing velocity of a group of intercollegiate baseball players. Twenty-four Division I collegiate baseball players (age: 19.7 +/- 1.3 years; height: 183.9 +/- 5.9 cm; mass: 90.7 +/- 10.5 kg) were recruited to participate in this study. Throwing velocity, isokinetic peak torque, isokinetic functional strength ratios, and time to peak torque were measured pre- and posttraining. Subjects were rank-ordered according to concentric internal rotation (IR) strength and were assigned randomly to either the plyometric training group (PLY) or the control group (CON). Training consisted of 6 upper extremity plyometric exercises ("Ballistic Six") performed twice per week for 8 weeks. Subjects assigned to CON performed regular off-season strength and conditioning activities, but did not perform plyometric activities. PLY demonstrated significant increases (p < 0.05) in throwing velocity following 8 weeks of training when compared with CON (83.15 mph [pre] vs. 85.15 mph [post]). There were no statistically significant differences in any of the isokinetic strength measurements between PLY and CON groups pre- to posttraining. Statistically significant differences were seen within PLY for concentric IR and eccentric external rotation (ER) isokinetic strength at 180 degrees x s(-1) and 300 degrees x s(-1); and within CON for eccentric ER isokinetic strength at 300 degrees x s(-1) and concentric IR isokinetic strength at 180 degrees x s(-1). The Ballistic Six training protocol can be a beneficial supplement to a baseball athlete's off-season conditioning by improving functional performance and strengthening the rotator cuff musculature.

  16. POSTOPERATIVE EFFECT OF PHYSICAL THERAPY RELATED TO FUNCTIONAL CAPACITY AND RESPIRATORY MUSCLE STRENGTH IN PATIENTS SUBMITTED TO BARIATRIC SURGERY

    PubMed Central

    de OLIVEIRA, Josélia Jucirema Jarschel; de FREITAS, Alexandre Coutinho Teixeira; de ALMEIDA, Andréa Adriana

    2016-01-01

    ABSTRACT Background: Respiratory physiotherapy plays an important role preventing complications in bariatric surgery. Aim: To assess the effects of out-patient physiotherapy during post-operative period through respiratory pressures and functional capacity in individuals submitted to bariatric surgery. Method: A prospective longitudinal and controlled study was done in adults with body mass index (BMI) equal or greater than 40 kg/m², who have been submitted to bariatric surgery. They were divided into two groups: intervention-group, who performed out-patient physiotherapy twice a week, from thirty to sixty days after surgery; and the control-group, who only followed home instructions. Both groups were evaluated before surgery and sixty days after surgery through manovacuometry, six-minute walk test and the Borg Scale of perceived exertion. Results: Twenty participants were included the intervention-group and twenty-three in the control-group. Both groups had significant and similar weight loss after surgery. The manovacuometry presented no differences comparing pre- and post-surgery and in the comparison between the groups. The result of the six-minute walk test for the intervention-group increased by 10.1% in the post-operative period in relation to pre-. The Borg scale of perceived exertion in the intervention-group in pre-surgery decreased by 13.5% in the post-surgery compared to pre-surgery. In the control-group there was no difference comparing pre- and post-operative values, as in the comparison with the intervention-group. Conclusion: The low-intensity exercise program, carried out between the 30th and the 60th day after bariatric surgery provided better functional capacity; did not change respiratory muscle strength; and improved the perceived exertion rate. PMID:27683775

  17. Increasing CRTC1 function in the dentate gyrus during memory formation or reactivation increases memory strength without compromising memory quality.

    PubMed

    Sekeres, Melanie J; Mercaldo, Valentina; Richards, Blake; Sargin, Derya; Mahadevan, Vivek; Woodin, Melanie A; Frankland, Paul W; Josselyn, Sheena A

    2012-12-01

    Memory stabilization following encoding (synaptic consolidation) or memory reactivation (reconsolidation) requires gene expression and protein synthesis (Dudai and Eisenberg, 2004; Tronson and Taylor, 2007; Nader and Einarsson, 2010; Alberini, 2011). Although consolidation and reconsolidation may be mediated by distinct molecular mechanisms (Lee et al., 2004), disrupting the function of the transcription factor CREB impairs both processes (Kida et al., 2002; Mamiya et al., 2009). Phosphorylation of CREB at Ser133 recruits CREB binding protein (CBP)/p300 coactivators to activate transcription (Chrivia et al., 1993; Parker et al., 1996). In addition to this well known mechanism, CREB regulated transcription coactivators (CRTCs), previously called transducers of regulated CREB (TORC) activity, stimulate CREB-mediated transcription, even in the absence of CREB phosphorylation. Recently, CRTC1 has been shown to undergo activity-dependent trafficking from synapses and dendrites to the nucleus in excitatory hippocampal neurons (Ch'ng et al., 2012). Despite being a powerful and specific coactivator of CREB, the role of CRTC in memory is virtually unexplored. To examine the effects of increasing CRTC levels, we used viral vectors to locally and acutely increase CRTC1 in the dorsal hippocampus dentate gyrus region of mice before training or memory reactivation in context fear conditioning. Overexpressing CRTC1 enhanced both memory consolidation and reconsolidation; CRTC1-mediated memory facilitation was context specific (did not generalize to nontrained context) and long lasting (observed after virally expressed CRTC1 dissipated). CREB overexpression produced strikingly similar effects. Therefore, increasing CRTC1 or CREB function is sufficient to enhance the strength of new, as well as established reactivated, memories without compromising memory quality.

  18. Global description of β- decay in even-even nuclei with the axially-deformed Skyrme finite-amplitude method

    NASA Astrophysics Data System (ADS)

    Mustonen, M. T.; Engel, J.

    2016-01-01

    We use the finite-amplitude method for computing charge-changing Skyrme-quasiparticle random-phase approximation (QRPA) transition strengths in axially-deformed nuclei together with a modern Skyrme energy-density functional to fit several previously unconstrained parameters in the charge-changing time-odd part of the functional. With the modified functional we then calculate rates of β- decay for all medium-mass and heavy even-even nuclei between the valley of stability and the neutron drip line. We fit the Skyrme parameters to a limited set of β -decay rates, a set of Gamow-Teller resonance energies, and a set of spin-dipole resonance energies, in both spherical and deformed nuclei. Comparison to available experimental β -decay rates shows agreement at roughly the same level as in other global QRPA calculations. We estimate the uncertainty in our rates all the way to the neutron drip line through a construction that extrapolates the errors of known β -decay rates in nuclei with intermediate Q values to less stable isotopes with higher Q values.

  19. Poor physical function in elderly women in low-level aged care is related to muscle strength rather than to measures of sarcopenia

    PubMed Central

    Woods, Julie L; Iuliano-Burns, Sandra; King, Susannah J; Strauss, Boyd J; Walker, Karen Z

    2011-01-01

    Purpose: To determine the prevalence of sarcopenia and investigate relationships among body composition, muscle strength, and physical function in elderly women in low-level aged care. Subjects and methods: Sixty-three ambulatory women (mean age 86 years) participated in this cross-sectional study where body composition was determined by dual energy X-ray absorptiometry (DXA); ankle, knee, and hip strength by the Nicholas Manual Muscle Tester; and physical function by ‘timed up and go’ (TUG) and walking speed (WS) over 6 meters. Body composition data from a female reference group (n = 62, mean age 29 years) provided cut-off values for defining sarcopenia. Results: Elderly women had higher body mass index (P < 0.001), lower lean mass (P < 0.001), and higher fat mass (P < 0.01) than the young reference group. Only a small proportion (3.2%) had absolute sarcopenia (defined by appendicular skeletal muscle mass/height squared) whereas 37% had relative sarcopenia class II (defined by percentage skeletal muscle mass). Scores for TUG and WS indicated relatively poor physical function, yet these measures were not associated with muscle mass or indices of sarcopenia. In multivariate analysis, only hip abductor strength predicted both TUG and WS (both P = 0.01). Conclusion: Hip strength is a more important indicator of physical functioning than lean mass. Measurement of hip strength may therefore be a useful screening tool to detect those at risk of functional decline and requirement for additional care. Further longitudinal studies with a range of other strength measures are warranted. PMID:21472094

  20. Report to the DOE Nuclear Data Committee, 1985

    SciTech Connect

    White, R.M.; Lanier, R.G.

    1985-02-01

    Progress is reported on the following measurements: the leakage multiplication from hollow beryllium spheres; /sup 6/Li and /sup 7/Li neutron-induced tritium production cross sections at 15 MeV; fast neutron fission yields; /sup 238/U(t,X) cross sections; neutron capture cross sections for /sup 86/ /sup 87/Sr at stellar temperatures; influence of realistic single particle spacings on precompound decay spectra; spontaneous fissions from a source of /sup 260/Md; and excitation functions from proton and deutron bombardment of natural Ti. Progress on the following calculations are reported: using modeled discrete levels; modeling level structures of odd-odd deformed nuclei; test of a phenomenological model of odd-odd deformed nuclei (an ARC study of /sup 176/Lu); absolute dipole gamma-ray strength functions for /sup 176/Lu; Gamow-Teller matrix elements for the /sup 11/B(p,n)/sup 11/C reaction at Ep = 26 MeV; K-distribution for neutron fission of /sup 232/Th; shell model study of the /sup 71/Ga(nu, anti e)/sup 71/Ge neutrino detector; and extension of microscopic models for neutron and proton scattering to inelastic scattering and charge-exchange reactions. Also, the status of the re-evaluation of the /sup 9/Be(n, 2n) reaction is given. (WHK)

  1. Efficacy of whey protein supplementation on resistance exercise-induced changes in muscle strength, lean mass, and function in mobility-limited older adults

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Whey protein supplementation may augment resistance exercise-induced increases in muscle strength and mass. Further studies are required to determine whether this effect extends to functionally compromised older adults. The objectives of the study were to compare the effects of whey protein concent...

  2. Parent Reports of Mental Health Concerns and Functional Impairment on Routine Screening with the Strengths and Difficulties Questionnaire

    PubMed Central

    Biel, Matthew G.; Kahn, Nicole F.; Srivastava, Anjuli; Mete, Mihriye; Banh, My K.; Wissow, Lawrence S.; Anthony, Bruno J.

    2015-01-01

    Objective This study used the Strengths and Difficulties Questionnaire (SDQ) to describe the prevalence of parent-reported mental health (MH) concerns in youth presenting for primary care appointments and to examine relationships between children’s MH issues and functional impairment. We hypothesized that increased MH symptomology would be associated with increased impairment and family burden. Methods Parents of 4–17 years old children were approached at routine visits in 13 primary care sites. Chi-square tests, independent samples t-tests, and a one-way analysis of variance (ANOVA) were used to make comparisons between demographic groups. Age-, sex-, and race-adjusted ordered logistic regression models and ANOVAs examined relationships between impact and SDQ scales. Results Boys had higher total Hyperactivity and Peer Problems. Adolescents showed higher Emotional Symptoms, while younger children showed more Hyperactivity. Latinos reported more Conduct Problems, Hyperactivity, and Peer Problems. Latinos also indicated less distress on the child, impairment at home and school, and family burden. Regression analyses indicated increased odds of impairment with higher scale scores. MH symptoms identified with the SDQ in pediatric primary care settings were associated with parent-reported impairment affecting youth and their families. Conclusions The presence of significant impairment suggests that parents’ concerns identified by screening are likely to be clinically important and worthy of practice strategies designed to promote assessment, treatment, and referral for these common problems. Identifying and exploring parents’ concerns with strategic use of screening tools may allow PCPs to directly engage families around the MH issues that affect them most. PMID:25922333

  3. The effects of water-based exercise in combination with blood flow restriction on strength and functional capacity in post-menopausal women.

    PubMed

    Araújo, Joamira P; Neto, Gabriel R; Loenneke, Jeremy P; Bemben, Michael G; Laurentino, Gilberto C; Batista, Gilmário; Silva, Júlio C G; Freitas, Eduardo D S; Sousa, Maria S C

    2015-12-01

    Water-based exercise and low-intensity exercise in combination with blood flow restriction (BFR) are two methods that have independently been shown to improve muscle strength in those of advancing age. The objective of this study was to assess the long-term effect of water-based exercise in combination with BFR on maximum dynamic strength and functional capacity in post-menopausal women. Twenty-eight women underwent an 8-week water-based exercise program. The participants were randomly allocated to one of the three groups: (a) water exercise only, (b) water exercise + BFR, or (c) a non-exercise control group. Functional capacity (chair stand test, timed up and go test, gait speed, and dynamic balance) and strength testing were tested before and after the 8-week aquatic exercise program. The main findings were as follows: (1) water-based exercise in combination with BFR significantly increased the lower limb maximum strength which was not observed with water-based exercise alone and (2) water-based exercise, regardless of the application of BFR, increased functional performance measured by the timed up and go test over a control group. Although we used a healthy population in the current study, these findings may have important implications for those who may be contraindicated to using traditional resistance exercise. Future research should explore this promising modality in these clinical populations.

  4. Effects of free leucine supplementation and resistance training on muscle strength and functional status in older adults: a randomized controlled trial

    PubMed Central

    Trabal, Joan; Forga, Maria; Leyes, Pere; Torres, Ferran; Rubio, Jordi; Prieto, Esther; Farran-Codina, Andreu

    2015-01-01

    Objective To assess the effect of free leucine supplementation combined with resistance training versus resistance training only on muscle strength and functional status in older adults. Methods This was a randomized, double-blind, placebo-controlled, parallel study with two intervention groups. Thirty older adults were randomly assigned to receive either 10 g leucine/day (leucine group [LG], n=15) or a placebo (control group [CG], n=15), plus resistance training over a 12-week period. Maximal overcoming isometric leg strength, functional status, nutritional status, body composition, health-related quality of life, depression, and dietary intake were assessed at 4 and 12 weeks. Missing data at 12 weeks were handled using mixed models for repeated measurements for data imputation. Results Twenty-four subjects completed the 4-week assessment and eleven completed the 12-week intervention. Clinically significant gains were found in isometric leg strength at both assessment time points. Analysis of the effect size also showed how participants in LG outperformed those in CG for chair stands and the timed up and go test. No significant changes were observed for the rest of the outcomes. Conclusion Our combined analysis showed moderate changes in isometric leg muscle strength and certain components of functional status. The magnitude of changes found on these outcomes should be qualified as a positive effect of the concomitant intervention. PMID:25926725

  5. Electron capture on iron group nuclei

    SciTech Connect

    Dean, D.J.; Chatterjee, L.; Strayer, M.R.; Dean, D.J.; Chatterjee, L.; Langanke, K.; Chatterjee, L.; Radha, P.B.

    1998-07-01

    We present Gamow-Teller strength distributions from shell model Monte Carlo studies of fp-shell nuclei that may play an important role in the precollapse evolution of supernovas. We then use these strength distributions to calculate the electron-capture cross sections and rates in the zero-momentum transfer limit. We also discuss the thermal behavior of the cross sections. We find large differences in these cross sections and rates when compared to the naive single-particle estimates. These differences need to be taken into account for improved modeling of the early stages of type-II supernova evolution. thinsp {copyright} {ital 1998} {ital The American Physical Society}

  6. Effect of an herbal/botanical supplement on strength, balance, and muscle function following 12-weeks of resistance training: a placebo controlled study

    PubMed Central

    2014-01-01

    Background StemSport (SS; StemTech International, Inc. San Clemente, CA) contains a proprietary blend of the botanical Aphanizomenon flos-aquae and several herbal antioxidant and anti-inflammatory substances. SS has been purported to accelerate tissue repair and restore muscle function following resistance exercise. Here, we examine the effects of SS supplementation on strength adaptations resulting from a 12-week resistance training program in healthy young adults. Methods Twenty-four young adults (16 males, 8 females, mean age = 20.5 ± 1.9 years, mass = 70.9 ± 11.9 kg, stature = 176.6 ± 9.9 cm) completed the twelve week training program. The study design was a double-blind, placebo controlled parallel group trial. Subjects either received placebo or StemSport supplement (SS; mg/day) during the training. 1-RM bench press, 1-RM leg press, vertical jump height, balance (star excursion and center of mass excursion), isokinetic strength (elbow and knee flexion/extension) and perception of recovery were measured at baseline and following the 12-week training intervention. Results Resistance training increased 1-RM strength (p < 0.008), vertical jump height (p < 0.03), and isokinetic strength (p < 0.05) in both SS and placebo groups. No significant group-by-time interactions were observed (all p-values >0.10). Conclusions These data suggest that compared to placebo, the SS herbal/botanical supplement did not enhance training induced adaptations to strength, balance, and muscle function above strength training alone. PMID:24910543

  7. Stability constants for the formation of lead chloride complexes as a function of temperature and ionic strength

    PubMed Central

    Luo, Yanxin; Millero, Frank J.

    2015-01-01

    The stability constants for the formation of lead (Pb2+) with chloride Pb2+=nCl−↔PbCln2−nβn(n=1,2,3) have been determined using a spectrophotometric method in NaClO4 solutions as a function of ionic strength (0–6 m) and temperature (15–45 °C). The results have been fitted to the equations: logβ1∗=logβ1+0.21I−8.61I0.5∕(1+1.2I0.5)+1927.40[I0.5∕(1+1.2I0.5)]∕Tlogβ2∗=logβ2+0.32I−4.67I0.5(1+1.2I0.5)+594.54[I0.5∕(1+1.2I0.5)]∕Tlogβ3∗=logβ3+0.40I−2.68I0.5(1+1.2I0.5)−43.98[I0.5∕(1+1.2I0.5)]∕T with standard errors of 0.05, 0.04 and 0.06, respectively. The thermodynamic values of log β1, logβ2 and logβ3 at 25.0 °C and the enthalpies of formation of PbCl+, PbCl20 and PbCl3− are in good agreement with literature values. We have combined our results with the earlier work of Seward (1984) to yield thermodynamic constants that are valid from 15 to 300 °C: logβ1=44.82+0.031T−21.21logTlogβ2=61.42+0.046T−29.51logTlogβ3=107.97+0.071T−51.46logT with standard errors of 0.05, 0.08 and 0.10, respectively. PMID:26937043

  8. Handgrip strength is an independent predictor of functional outcome in hip-fracture women: a prospective study with 6-month follow-up.

    PubMed

    Di Monaco, Marco; Castiglioni, Carlotta; De Toma, Elena; Gardin, Luisa; Giordano, Silvia; Tappero, Rosa

    2015-02-01

    The objective of this study was to investigate the contribution of handgrip strength in predicting the functional outcome after hip fracture in women.We prospectively investigated white women (N = 193 of 207) who were consecutively admitted to a rehabilitation hospital after a hip fracture. We measured handgrip strength with a Jamar dynamometer (Lafayette Instrument Co, Lafayette, IN), on admission to rehabilitation. Ability to function in activities of daily living was assessed by the Barthel index both on discharge from rehabilitation and at a 6-month follow-up.We found significant correlations between handgrip strength measured before rehabilitation and Barthel index scores assessed both on discharge from rehabilitation (ρ = 0.52, P < 0.001) and after 6 months (ρ = 0.49, P < 0.001). Significant associations between handgrip strength and Barthel index scores persisted after adjustment for age, comorbidities, pressure ulcers, medications in use, concomitant infections, body mass index, hip-fracture type, and Barthel index scores assessed both preinjury and on admission to rehabilitation (P = 0.001). Further adjustments for both Barthel index scores and Timed Up-and-Go test assessed at rehabilitation ending did not erase the significant association between handgrip strength and the Barthel index scores at the 6-month evaluation (P = 0.007). To define successful rehabilitation, we categorized the Barthel index scores as either high (85 or higher) or low (<85). The adjusted odds ratio for 1 SD increase in grip strength was 1.73 (95% confidence interval [CI] 1.05-2.84, P = 0.032) for having a high Barthel index score at the end of inpatient rehabilitation and 2.24 (95% CI 1.06-5.18) for having a high Barthel index score at the 6-month follow-up.Handgrip strength assessed before rehabilitation independently predicted the functional outcome both after inpatient rehabilitation and at a 6-month follow-up in hip-fracture women.

  9. 2004 Progress Report for Grant No. DE-FG03-03NA00076 Nuclear Level Densities and Gamma-ray Strength Functions: Stewardship Sciences Academic Alliances Program

    SciTech Connect

    G. E. Mitchell

    2004-10-18

    To verify the apparent large enhancement of the radiative strength function in light and medium nuclei, the 56Fe(n,2gamma)57Fe reaction was measured. The two-step cascade intensities with soft primary intensities confirm the enhancement. The combined results have been published in Physical Review Letters and featured in the Physics News Update. Data for the Yb isotopes have been combined to examine the systematics of level densities and strength function in three Yb isotopes. A paper on these results have been accepted for publication in Physical Review C. Analysis of the gamma rays from neutron induced reactions on 48Ti have been measured and analyzed for neturon energies from 1 to 250 MeV.

  10. The effects of an exercise training program on hand and wrist strength, and function, and activities of daily living, in adults with severe cerebral palsy.

    PubMed

    Hutzler, Yeshayahu; Lamela Rodríguez, Beatriz; Mendoza Laiz, Nuria; Díez, Isabel; Barak, Sharon

    2013-12-01

    The purpose of the current study was to establish measurement reliability in adults with Cerebral Palsy (CP), and to examine the feasibility and outcomes of an upper extremity strength training program (three times per week for 90 min each time). A control group design mixed with a prospective time series design for the intervention group was completed, including a pre-test, a post-test after a 12-week intervention period, and a follow-up in the intervention group after an additional 10-week period. Seventeen adults with CP with severe motor impairment took part in the study (10 in the intervention and seven in the control group). The test battery was comprised of wrist and hand dynamometry; dominant hand upper-extremity function measures (Jebsen Hand Function Test=JHFT, Minnesota Manual Dexterity Test=MMDT, and the Nine Hole Peg Test=NHPT); and activity of daily living with the Barthel Index. The results indicated that in both the control and the intervention groups, the strength tests exhibited good-to-excellent reliability during pre-test and post-test. The group comparison revealed that while in the pre-test no between-group differences existed, in the post-test the strength training group demonstrated significantly higher values in five out of eight strength measures, as well as in the MMDT. Discontinuing the program for eight weeks reversed the effects almost to baseline. In conclusion, the outcomes demonstrated the reliability of the assessments utilized in this study, as well as the feasibility of the strength training program, in adults with severe motor impairment due to CP.

  11. Does hydrotherapy improve strength and physical function in patients with osteoarthritis—a randomised controlled trial comparing a gym based and a hydrotherapy based strengthening programme

    PubMed Central

    Foley, A; Halbert, J; Hewitt, T; Crotty, M

    2003-01-01

    Objective: To compare the effects of a hydrotherapy resistance exercise programme with a gym based resistance exercise programme on strength and function in the treatment of osteoarthritis (OA). Design: Single blind, three arm, randomised controlled trial. Subjects: 105 community living participants aged 50 years and over with clinical OA of the hip or knee. Methods: Participants were randomised into one of three groups: hydrotherapy (n = 35), gym (n = 35), or control (n = 35). The two exercising groups had three exercise sessions a week for six weeks. At six weeks an independent physiotherapist unaware of the treatment allocation performed all outcome assessments (muscle strength dynamometry, six minute walk test, WOMAC OA Index, total drugs, SF-12 quality of life, Adelaide Activities Profile, and the Arthritis Self-Efficacy Scale). Results: In the gym group both left and right quadriceps significantly increased in strength compared with the control group, and right quadriceps strength was also significantly better than in the hydrotherapy group. The hydrotherapy group increased left quadriceps strength only at follow up, and this was significantly different from the control group. The hydrotherapy group was significantly different from the control group for distance walked and the physical component of the SF-12. The gym group was significantly different from the control group for walk speed and self efficacy satisfaction. Compliance rates were similar for both exercise groups, with 84% of hydrotherapy and 75% of gym sessions attended. There were no differences in drug use between groups over the study period. Conclusion: Functional gains were achieved with both exercise programmes compared with the control group. PMID:14644853

  12. Silicone foul release coatings: effect of the interaction of oil and coating functionalities on the magnitude of macrofouling attachment strengths.

    PubMed

    Stein, Judith; Truby, Kathryn; Wood, Christina Darkangelo; Stein, Jeff; Gardner, Martha; Swain, Geoffrey; Kavanagh, Christopher; Kovach, Brett; Schultz, Michael; Wiebe, Deborah; Holm, Eric; Montemarano, Jean; Wendt, Dean; Smith, Celia; Meyer, Anne

    2003-04-01

    Silicone biofouling release coatings have been shown to be an effective method of combating fouling. Nearly all silicone foul release coatings are augmented with an oil additive to decrease macrofouling attachment strength. This paper addresses the effect of the type of oil that is incorporated into the silicone coating and the type of silicone coating itself (silica vs calcium carbonate filled) on macrofouling adhesion strengths to the coating. It was found that not only are the main effects of oil type and silicone coating type important in determining the magnitude of the attachment strength of the organism, but the interaction term (oil type crossed with coating type) is highly significant for all organisms studied, except oysters at the University of Hawaii test site (Oahu, Hawaii) which has a significance level of alpha = 0.1. Each of the organisms exhibited a unique response to the various silicone fouling release coatings. Thus, in order to predict the effectives of foul release coatings, the composition variables of the coatings and the type of target organisms must be considered.

  13. Double-β decay nuclear structure via electron capture on ^116In

    NASA Astrophysics Data System (ADS)

    Wrede, C.; Sjue, S. K. L.; García, A. A.; Swanson, H. E.; Ahmad, I.; Algora, A.; Elomaa, V.-V.; Eronen, T.; Hakala, J.; Jokinen, A.; Kolhinen, V. S.; Moore, I. D.; Penttilä, H.; Reponen, M.; Rissanen, J.; Saastamoinen, A.; Äystö, J.

    2013-04-01

    The small electron-capture decay branch of ^116In has been measured using Penning trap assisted decay spectroscopy. The deduced Gamow-Teller transition strength helps to resolve longstanding differences between scattered charge-exchange reaction values and a previous electron-capture decay value that was less statistically significant than the present one. We argue that this transition can now be used as a reliable benchmark for nuclear-structure calculations of the matrix element for the neutrinoless double-β decay of ^116Cd and other nuclides.

  14. Conversion coefficients of the isomeric state in {sup 72}Br

    SciTech Connect

    Briz, J. A.; Borge, M. J. G.; Maira, A.; Perea, A.; Tengblad, O.; Agramunt, J.; Algora, A.; Estevez, E.; Nacher, E.; Rubio, B.; Fraile, L. M.; Deo, A.; Farrelly, G.; Gelletly, W.; Podolyak, Z.

    2010-04-26

    In order to determine the Gamow-Teller strength distribution for the N Z nucleus {sup 72}Kr an experiment was performed with a Total Absorption Gamma Spectrometer. To fully accomplish this task it is crucial to determine the multipolarity of the low energy transitions as the spin-parity of the daughter ground state has been debated. This is done by experimental determination of the conversion coefficients. Preliminary results for the multipolarity and conversion coefficients of the transition connecting the isomeric state at 101 keV with the {sup 72}Br ground state are presented.

  15. Calculation of delayed-neutron energy spectra in a QRPA-Hauser-Feshbach model

    SciTech Connect

    Kawano, Toshihiko; Moller, Peter; Wilson, William B

    2008-01-01

    Theoretical {beta}-delayed-neutron spectra are calculated based on the Quasiparticle Random-Phase Approximation (QRPA) and the Hauser-Feshbach statistical model. Neutron emissions from an excited daughter nucleus after {beta} decay to the granddaughter residual are more accurately calculated than in previous evaluations, including all the microscopic nuclear structure information, such as a Gamow-Teller strength distribution and discrete states in the granddaughter. The calculated delayed-neutron spectra agree reasonably well with those evaluations in the ENDF decay library, which are based on experimental data. The model was adopted to generate the delayed-neutron spectra for all 271 precursors.

  16. Detailed {beta}-decay study of {sup 33}Ar

    SciTech Connect

    Adimi, N.; Dominguez-Reyes, R.; Alcorta, M.; Borge, M. J. G.; Madurga, M.; Perea, A.; Tengblad, O.; Bey, A.; Blank, B.; Dossat, C.; Giovinazzo, J.; Matea, I.; Fynbo, H. O. U.; Knudsen, H. H.; Suemmerer, K.

    2010-02-15

    The proton-rich nucleus {sup 33}Ar has been studied by detailed proton and {gamma}-ray spectroscopy at the low-energy facility of SPIRAL at GANIL. Proton and {gamma}-ray singles and coincidence measurements allowed to establish a quasicomplete decay scheme of this nucleus. By comparing the proton intensity to different daughter states, tentative spin assignments have been made for some of the states of {sup 33}Cl. The Gamow-Teller strength distribution is deduced and compared to shell-model calculations and a quenching factor is determined. States close to the isobaric analog state are searched for with respect to isospin mixing.

  17. Strength Testing.

    ERIC Educational Resources Information Center

    Londeree, Ben R.

    1981-01-01

    Postural deviations resulting from strength and flexibility imbalances include swayback, scoliosis, and rounded shoulders. Screening tests are one method for identifying strength problems. Tests for the evaluation of postural problems are described, and exercises are presented for the strengthening of muscles. (JN)

  18. Effects of Pilates mat exercises on muscle strength and on pulmonary function in patients with cystic fibrosis*

    PubMed Central

    Franco, Caroline Buarque; Ribeiro, Antonio Fernando; Morcillo, André Moreno; Zambon, Mariana Porto; Almeida, Marina Buarque; Rozov, Tatiana

    2014-01-01

    OBJECTIVE: To analyze the effects of Pilates mat exercises in patients with cystic fibrosis (CF). METHODS: This was a clinical trial involving 19 CF patients recruited from either the CF Outpatient Clinic of the State University at Campinas Hospital de Clínicas or the Children's Institute of the University of São Paulo School of Medicine Hospital das Clínicas. All of the patients performed Pilates mat exercises for four months (one 60-min session per week). The variables studied (before and after the intervention) were respiratory muscle strength, MIP, MEP, FVC, and FEV1. RESULTS: After the intervention, MIP was significantly higher in the male patients (p = 0.017), as were MIP and MEP in the female patients (p = 0.005 and p = 0.007, respectively). There were no significant differences between the pre- and post-intervention values of FVC or FEV1, neither in the sample as a whole nor among the patients of either gender. CONCLUSIONS: Our results show that Pilates mat exercises have beneficial effects on respiratory muscle strength in CF patients. PMID:25410840

  19. Intermediate filament–membrane attachments function synergistically with actin-dependent contacts to regulate intercellular adhesive strength

    PubMed Central

    Huen, Arthur C.; Park, Jung K.; Godsel, Lisa M.; Chen, Xuejun; Bannon, Leslie J.; Amargo, Evangeline V.; Hudson, Tracie Y.; Mongiu, Anne K.; Leigh, Irene M.; Kelsell, David P.; Gumbiner, Barry M.; Green, Kathleen J.

    2002-01-01

    By tethering intermediate filaments (IFs) to sites of intercellular adhesion, desmosomes facilitate formation of a supercellular scaffold that imparts mechanical strength to a tissue. However, the role IF–membrane attachments play in strengthening adhesion has not been directly examined. To address this question, we generated Tet-On A431 cells inducibly expressing a desmoplakin (DP) mutant lacking the rod and IF-binding domains (DPNTP). DPNTP localized to the plasma membrane and led to dissociation of IFs from the junctional plaque, without altering total or cell surface distribution of adherens junction or desmosomal proteins. However, a specific decrease in the detergent-insoluble pool of desmoglein suggested a reduced association with the IF cytoskeleton. DPNTP-expressing cell aggregates in suspension or substrate-released cell sheets readily dissociated when subjected to mechanical stress whereas controls remained largely intact. Dissociation occurred without lactate dehydrogenase release, suggesting that loss of tissue integrity was due to reduced adhesion rather than increased cytolysis. JD-1 cells from a patient with a DP COOH-terminal truncation were also more weakly adherent compared with normal keratinocytes. When used in combination with DPNTP, latrunculin A, which disassembles actin filaments and disrupts adherens junctions, led to dissociation up to an order of magnitude greater than either treatment alone. These data provide direct in vitro evidence that IF–membrane attachments regulate adhesive strength and suggest furthermore that actin- and IF-based junctions act synergistically to strengthen adhesion. PMID:12499357

  20. Effects of creatine supplementation and three days of resistance training on muscle strength, power output, and neuromuscular function.

    PubMed

    Cramer, Joel T; Stout, Jeffrey R; Culbertson, Julie Y; Egan, Alison D

    2007-08-01

    Previous studies have demonstrated increases in peak torque (PT) and decreases in acceleration time (ACC) after only 2 days of resistance training, and other studies have reported improvements in isokinetic performance after 5 days of creatine supplementation. Consequently, there may be a combined benefit of creatine supplementation and short-term resistance training for eliciting rapid increases in muscle strength, which may be important for short-term rehabilitation and return-to-play for previously injured athletes. The purpose of this study, therefore, was to examine the effects of 3 days of isokinetic resistance training combined with 8 days of creatine monohydrate supplementation on PT, mean power output (MP), ACC, surface electromyography (EMG), and mechanomyography (MMG) of the vastus lateralis muscle during maximal concentric isokinetic leg extension muscle actions. Twenty-five men (mean age +/- SD = 21 +/- 3 years, stature = 177 +/- 6 cm, and body mass = 80 +/- 12 kg) volunteered to participate in this 9-day, double-blind, placebo-controlled study and were randomly assigned to either the creatine (CRE; n = 13) or placebo (PLA; n = 12) group. The CRE group ingested the treatment drink (280 kcal; 68 g carbohydrate; 10.5 g creatine), whereas the PLA group received an isocaloric placebo (70 g carbohydrate). Two servings per day (morning and afternoon) were administered in the laboratory on days 1-6, with only 1 serving on days 7-8. Before (pre; day 1) and after (post; day 9) the resistance training, maximal voluntary concentric isokinetic leg extensions at 30, 150, and 270 degrees x s(-1) were performed on a calibrated Biodex System 3 dynamometer. Three sets of 10 repetitions at 150 degrees x s(-1) were performed on days 3, 5, and 7. Peak torque increased (p = 0.005; eta(2) = 0.296), whereas ACC decreased (p < 0.001; eta(2) = 0.620), from pretraining to posttraining for both the CRE and PLA groups at each velocity (30, 150, and 270 degrees x s(-1)). Peak

  1. Stability constants for the formation of rare earth-inorganic complexes as a function of ionic strength

    NASA Astrophysics Data System (ADS)

    Millero, Frank J.

    1992-08-01

    Recent studies have been made on the distribution of the rare earths (La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) in natural waters relative to their concentration in shales. These metals have also been used as models for the behavior of the trivalent actinides. The speciation of the rare earths in natural waters is modelled by using ionic interaction models which require reliable stability constants. In this paper the stability constants for the formation of lanthanide complexes ( k mx∗) with Cl -, NO 3-, SO 42-, OH -, HCO 3-, H 2PO 4-, HPO 42-, and CO 32- determined in NaClO 44 at various ionic strengths have been extrapolated to infinite dilution using the Pitzer interaction model. The activity coefficients for free ions ( γM, γx) needed for this extrapolation have been estimated from the Pitzer equations. The thermodynamic stability constants ( KMX) and activity coefficients of the various ion pairs ( γMX) were determined from In ( solK MX∗/γ Mγ x) = In K mx+ In (γ MX). The activity coefficients of the ion pairs have been used to determine Pitzer parameters ( BMX) for the rare earth complexes. The values of BMX were found to be the same for complexes of the same charge. These results make it possible to estimate the stability constants for the formation of rare earth complexes over a wide range of ionic strengths. The stability constants have been used to determine the speciation of the lanthanides in seawater and in brines. The carbonate complexes dominate for all natural waters where the carbonate alkalinity is greater than 0.001 eq/L at a pH near 8.

  2. Upper Limb Strength and Function Changes during a One-Year Follow-Up in Non-Ambulant Patients with Duchenne Muscular Dystrophy: An Observational Multicenter Trial

    PubMed Central

    Seferian, Andreea Mihaela; Moraux, Amélie; Annoussamy, Mélanie; Canal, Aurélie; Decostre, Valérie; Diebate, Oumar; Le Moing, Anne-Gaëlle; Gidaro, Teresa; Deconinck, Nicolas; Van Parys, Frauke; Vereecke, Wendy; Wittevrongel, Sylvia; Mayer, Michèle; Maincent, Kim; Desguerre, Isabelle; Thémar-Noël, Christine; Cuisset, Jean-Marie; Tiffreau, Vincent; Denis, Severine; Jousten, Virginie; Quijano-Roy, Susana; Voit, Thomas; Hogrel, Jean-Yves; Servais, Laurent

    2015-01-01

    Introduction Upper limb evaluation of patients with Duchenne Muscular Dystrophy is crucially important to evaluations of efficacy of new treatments in non-ambulant patients. In patients who have lost ambulation, there are few validated and informative outcome measures. In addition, longitudinal data demonstrating sensitivity to clinical evolution of outcome measures over short-term periods are lacking. Patients and Methods We report here the results of a one-year multicenter study using specifically designed tools to assess grip, pinch strength, and hand function in wheelchair-bound patients. Our study assessed 53 non-ambulant patients with Duchenne muscular dystrophy aged 17.1 ± 4.8 years (range: 9 – 28.1 years). The average Brooke functional score of these patients was 4.6 ± 1.1. The average forced vital capacity was 44.5% predicted and 19 patients used non-invasive ventilation. Patients were assessed at baseline, 6 months, and one year using the Motor Function Measure and innovative devices (namely the MyoSet composed of MyoGrip, MyoPinch, and MoviPlate). Results Our study confirmed preliminary data previously reported regarding feasibility of use and of reliability of the MyoSet and the correlation at baseline between distal strength and clinical outcomes such as FVC, Brooke score, age, and duration since loss of ambulation. A significant correlation was observed between the distal upper limb strength and clinical variables. The sensitive dynamometers (MyoGrip and MyoPinch) and MoviPlate captured a 12-month change in non-ambulant Duchenne muscular dystrophy patients of all ages. Trial Registration ClinicalTrials.gov NCT00993161 NCT00993161 PMID:25643053

  3. Hindlimb Skeletal Muscle Function and Skeletal Quality and Strength in +/G610C Mice With and Without Weight-Bearing Exercise.

    PubMed

    Jeong, Youngjae; Carleton, Stephanie M; Gentry, Bettina A; Yao, Xiaomei; Ferreira, J Andries; Salamango, Daniel J; Weis, MaryAnn; Oestreich, Arin K; Williams, Ashlee M; McCray, Marcus G; Eyre, David R; Brown, Marybeth; Wang, Yong; Phillips, Charlotte L

    2015-10-01

    Osteogenesis imperfecta (OI) is a heterogeneous heritable connective tissue disorder associated with reduced bone mineral density and skeletal fragility. Bone is inherently mechanosensitive, with bone strength being proportional to muscle mass and strength. Physically active healthy children accrue more bone than inactive children. Children with type I OI exhibit decreased exercise capacity and muscle strength compared with healthy peers. It is unknown whether this muscle weakness reflects decreased physical activity or a muscle pathology. In this study, we used heterozygous G610C OI model mice (+/G610C), which model both the genotype and phenotype of a large Amish OI kindred, to evaluate hindlimb muscle function and physical activity levels before evaluating the ability of +/G610C mice to undergo a treadmill exercise regimen. We found +/G610C mice hindlimb muscles do not exhibit compromised muscle function, and their activity levels were not reduced relative to wild-type mice. The +/G610C mice were also able to complete an 8-week treadmill regimen. Biomechanical integrity of control and exercised wild-type and +/G610C femora were analyzed by torsional loading to failure. The greatest skeletal gains in response to exercise were observed in stiffness and the shear modulus of elasticity with alterations in collagen content. Analysis of tibial cortical bone by Raman spectroscopy demonstrated similar crystallinity and mineral/matrix ratios regardless of sex, exercise, and genotype. Together, these findings demonstrate +/G610C OI mice have equivalent muscle function, activity levels, and ability to complete a weight-bearing exercise regimen as wild-type mice. The +/G610C mice exhibited increased femoral stiffness and decreased hydroxyproline with exercise, whereas other biomechanical parameters remain unaffected, suggesting a more rigorous exercise regimen or another exercise modality may be required to improve bone quality of OI mice.

  4. Functionally Gradient Material Ceramics of Hydroxyapatite and Yttria Partially Stabilized Zirconia Prepared by Spark Plasma Sintering for Biocompatibility and Mechanical Strength

    NASA Astrophysics Data System (ADS)

    Kawagoe, Daisuke; Eda, Hokuto; Shinohara, Akiko; Nakata, Satoshi

    2013-01-01

    Hydroxyapatite, Ca10(PO4)6(OH)2: HA, is biocompatible with human hard tissue. Zirconia has mechanical strength and toughness. Spark plasma sintering (SPS) is a processing technique that makes it possible to prepare materials at low temperatures. Therefore, the objective of this study is to use the SPS method to prepare functionally gradient material (FGM) ceramics with the biocompatibility of HA and the strength of yttria partially stabilized zirconia (Y-PSZ). Fine powders of HA and Y-PSZ (ZrO2 + 3 mol % Y2O3) were poured into the graphite mold and then subjected to SPS at 1100 °C for 10 min. The outer layer has a mixing ratio of 70 wt % HA : 30 wt % Y-PSZ and the other layers are deposited by gradually changing the mixing ratio of HA and Y-PAZ. Each layer in the obtained composite (1.5 mmφ × 1.7 mm) was approximately 0.25 mm thick. The measured compressive strength of the composite prepared by SPS at 1100 °C for 10 min was 950 MPa.

  5. Effects of transcutaneous electrical nerve stimulation on pain, walking function, respiratory muscle strength and vital capacity in kidney donors: a protocol of a randomized controlled trial

    PubMed Central

    2013-01-01

    Background Pain is a negative factor in the recovery process of postoperative patients, causing pulmonary alterations and complications and affecting functional capacity. Thus, it is plausible to introduce transcutaneous electrical nerve stimulation (TENS) for pain relief to subsequently reduce complications caused by this pain in the postoperative period. The objective of this paper is to assess the effects of TENS on pain, walking function, respiratory muscle strength and vital capacity in kidney donors. Methods/design Seventy-four patients will be randomly allocated into 2 groups: active TENS or placebo TENS. All patients will be assessed for pain intensity, walk function (Iowa Gait Test), respiratory muscle strength (maximal inspiratory pressure and maximal expiratory pressure) and vital capacity before and after the TENS application. The data will be collected by an assessor who is blinded to the group allocation. Discussion This study is the first to examine the effects of TENS in this population. TENS during the postoperative period may result in pain relief and improvements in pulmonary tests and mobility, thus leading to an improved quality of life and further promoting organ donation. Trial registration Registro Brasileiro de Ensaios Clinicos (ReBEC), number RBR-8xtkjp. PMID:23311705

  6. Strength nutrition.

    PubMed

    Volek, Jeff S

    2003-08-01

    Muscle strength is determined by muscle size and factors related to neural recruitment. Resistance training is a potent stimulus for increasing muscle size and strength. These increases are, to a large extent, influenced and mediated by changes in hormones that regulate important events during the recovery process following exercise. Provision of nutrients in the appropriate amounts and at the appropriate times is necessary to optimize the recovery process. This review discusses the results of research that has examined the potential for nutrition and dietary supplements to impact the acute response to resistance exercise and chronic adaptations to resistance training. To date, the most promising strategies to augment gains in muscle size and strength appear to be consumption of protein-carbohydrate calories before and after resistance exercise, and creatine supplementation.

  7. Investigation of the ionic strength dependence of Ulva lactuca acid functional group pK(a)s by manual alkalimetric titrations.

    PubMed

    Schijf, Johan; Ebling, Alina M

    2010-03-01

    We performed a series of manual alkalimetric titrations in NaCl solutions (0.01-5.0 M) at T = 25 degrees C on both fresh and dehydrated samples of the marine chlorophyte Ulva lactuca (sea lettuce), a strong metal accumulator holding considerable promise in biosorbent and biomonitor applications. Functional groups were characterized in terms of their number, site densities, and acid dissociation constants (pK(a)s). FITEQL4.0 modeling shows that, at any ionic strength, titration curves for dehydrated biomass in the pH range 2-10 are adequately described by three functional groups with remarkably uniform site densities of about 5 x 10(-4) mol/g. Lower site densities for fresh U. lactuca are consistent with approximately 87% water content. The pK(a)s display pronounced ionic strength dependent behavior obeying an extended Debye-Huckel relation. Extrapolation to I = 0 yields values of 4.26 +/- 0.04, 6.44 +/- 0.02, and 9.56 +/- 0.04. This information by itself is insufficient to unambiguously identify the groups. Similar site densities suggest that all three are linked to major molecular building blocks of the cell material, pointing to carboxylic acids, phosphate esters, and amines as likely candidates. Highly acidic sulfate esters, not detected in our titrations, may also play a role in trace metal adsorption on U. lactuca.

  8. Effects of Group-Based Exercise on Range of Motion, Muscle Strength, Functional Ability, and Pain During the Acute Phase After Total Knee Arthroplasty: A Controlled Clinical Trial.

    PubMed

    Hiyama, Yoshinori; Kamitani, Tsukasa; Wada, Osamu; Mizuno, Kiyonori; Yamada, Minoru

    2016-09-01

    Study Design Prospective observational study including a historical control group. Background The extent to which group-based exercise (G-EXE) improves knee range of motion (ROM), quadriceps strength, and gait ability is similar to that of individualized exercise (I-EXE) at 6 weeks and 8 months after total knee arthroplasty (TKA). However, the benefits of G-EXE for patients during the acute recovery phase after TKA remain unclear. Objective To determine the effects of G-EXE during the acute recovery phase after TKA on knee ROM, quadriceps strength, functional ability, and knee pain. Methods Two hundred thirty-one patients participated in G-EXE in addition to regular ambulation and activities-of-daily-living exercises twice daily during the hospital stay. Outcomes were compared to those of a retrospectively identified, historical control group (I-EXE group [n = 206]) that included patients who performed exercises identical to those performed by the G-EXE group. The outcomes included knee ROM, quadriceps strength, pain intensity, and timed up-and-go test score at 1 month before surgery and at discharge. Analyses were adjusted for age, body mass index, sex, length of hospital stay, and preoperative values. Results Changes in ROM of knee flexion and extension (P<.001) and quadriceps strength (P<.001) were significantly better in the G-EXE group than those in the I-EXE group at discharge. The pain intensity improved more in the G-EXE group than in the I-EXE group at discharge (P<.001). However, the changes in the timed up-and-go scores were not significantly different. Conclusion Patients performing G-EXE in addition to regular ambulation and activities-of-daily-living exercises demonstrated greater changes in knee ROM, quadriceps strength, and knee pain than those performing I-EXE in addition to regular ambulation and activities-of-daily-living exercises. The nonrandomized, asynchronous design decreases certainty of these findings. Level of Evidence Therapy, level 2b

  9. Effect of tighter glycemic control on cardiac function, exercise capacity, and muscle strength in heart failure patients with type 2 diabetes: a randomized study

    PubMed Central

    Nielsen, Roni; Wiggers, Henrik; Thomsen, Henrik Holm; Bovin, Ann; Refsgaard, Jens; Abrahamsen, Jan; Møller, Niels; Bøtker, Hans Erik; Nørrelund, Helene

    2016-01-01

    Objectives In patients with type 2 diabetes (T2D) and heart failure (HF), the optimal glycemic target is uncertain, and evidence-based data are lacking. Therefore, we performed a randomized study on the effect of optimized glycemic control on left ventricular function, exercise capacity, muscle strength, and body composition. Design and methods 40 patients with T2D and HF (left ventricular ejection fraction (LVEF) 35±12% and hemoglobin A1c (HbA1c) 8.4±0.7% (68±0.8 mmol/mol)) were randomized to either 4-month optimization (OPT group) or non-optimization (non-OPT group) of glycemic control. Patients underwent dobutamine stress echocardiography, cardiopulmonary exercise test, 6 min hall-walk test (6-MWT), muscle strength examination, and dual X-ray absorptiometry scanning at baseline and at follow-up. Results 39 patients completed the study. HbA1c decreased in the OPT versus the non-OPT group (8.4±0.8% (68±9 mmol/mol) to 7.6±0.7% (60±7 mmol/mol) vs 8.3±0.7% (67±10 mmol/mol) to 8.4±1.0% (68±11 mmol/mol); p<0.001). There was no difference between the groups with respect to changes in myocardial contractile reserve (LVEF (p=0.18)), oxygen consumption (p=0.55), exercise capacity (p=0.12), and 6-MWT (p=0.84). Muscle strength decreased in the non-OPT compared with the OPT group (37.2±8.1 to 34.8±8.3 kg vs 34.9±10.2 to 35.4±10.7 kg; p=0.01), in line with a non-significant decrease in lean (p=0.07) and fat (p=0.07) tissue mass in the non-OPT group. Hypoglycemia and fluid retention did not differ between groups. Conclusions 4 months of optimization of glycemic control was associated with preserved muscle strength and lean body mass in patients with T2D and HF compared with lenient control, and had no deleterious effect on left ventricular contractile function and seemed to be safe. Trial registration number NCT01213784; pre-results. PMID:27158520

  10. Can Quantitative Muscle Strength and Functional Motor Ability Differentiate the Influence of Age and Corticosteroids in Ambulatory Boys with Duchenne Muscular Dystrophy?

    PubMed Central

    Buckon, Cathleen; Sienko, Susan; Bagley, Anita; Sison-Williamson, Mitell; Fowler, Eileen; Staudt, Loretta; Heberer, Kent; McDonald, Craig M.; Sussman, Michael

    2016-01-01

    Background: In the absence of a curative treatment for Duchenne Muscular Dystrophy (DMD), corticosteroid therapy (prednisone, deflazacort) has been adopted as the standard of care, as it slows the progression of muscle weakness and enables longer retention of functional mobility. The ongoing development of novel pharmacological agents that target the genetic defect underlying DMD offer hope for a significant alteration in disease progression; however, substantiation of therapeutic efficacy has proved challenging. Identifying functional outcomes sensitive to the early, subtle changes in muscle function has confounded clinical trials. Additionally, the alterations in disease progression secondary to corticosteroid therapy are not well described making it difficult to ascertain the benefits of novel agents, often taken concurrently with corticosteroids. Objective: The purpose of this study was to examine outcome responsiveness to corticosteroid therapy and age at the onset of a natural history study of ambulatory boys with DMD. Methods: Eighty-five ambulatory boys with DMD (mean age 93 mo, range 49 to 180 mo) were recruited into this study. Fifty participants were on corticosteroid therapy, while 33 were corticosteroid naïve at the baseline assessment. Within each treatment group boys were divided in two age groups, 4 to 7 years and 8 and greater years of age. The Biodex System 3 Pro isokinetic dynamometer was used to assess muscle strength. Motor skills were assessed using the upper two dimensions (standing/walking, running & jumping) of the Gross Motor Function Measure (GMFM 88) and Timed Motor Tests (TMTs) (10-meter run, sit to stand, supine to stand, climb 4-stairs). Two way analysis of variance and Pearson correlations were used for analysis. Results: A main effect for age was seen in select lower extremity muscle groups (hip flexors, knee extensors and ankle dorsiflexors), standing dimension skills, and all TMTs with significantly greater weakness and loss of

  11. Robotics and Gaming to Improve Ankle Strength, Motor Control, and Function in Children With Cerebral Palsy — A Case Study Series

    PubMed Central

    Burdea, Grigore C.; Cioi, Daniel; Kale, Angad; Janes, William E.; Ross, Sandy A.; Engsberg, Jack R.

    2014-01-01

    Objective To investigate the feasibility of game-based robotic training of the ankle in children with cerebral palsy (CP). Design Case study, 12 weeks intervention, with no follow-up. Setting University research laboratory. Participants A referred sample of 3 children with cerebral palsy, age 7 to 12, all male were enrolled. Three completed the intervention. Interventions Participants trained on the RA CP system for 36 rehabilitation sessions (12 weeks, 3 times/week), playing two custom virtual reality games. The games were played while participants were seated, and trained one ankle at-a-time for strength, motor control, and coordination. Main Outcome Measures The primary study outcome measures were for impairment (DF/PF torques, DF initial contact angle and gait speed), function (GMFM) and quality of life (Peds QL). Secondary outcome measures relate to game performance (game scores as reflective of ankle motor control and endurance). Results Gait function improved substantially in ankle kinematics, speed and endurance. Overall function (GMFM) indicated improvements that were typical of other ankle strength training programs. Quality of life increased beyond what would be considered a minimal clinical important difference. Game performance improved in both games during the intervention. Conclusions This feasibility study supports the assumption that game-based robotic training of the ankle benefits gait in children with CP. Game technology is appropriate for the age group and was well accepted by the participants. Additional studies are needed however, to quantify the level of benefit and compare the approach presented here to traditional methods of therapy. PMID:22773059

  12. Oscillator strengths and collision strengths for S III

    NASA Technical Reports Server (NTRS)

    Ho, Y. K.; Henry, R. J. W.

    1984-01-01

    The present calculation, in a close-coupled approximation for the energy range up to 1,000,000 K, yields collision strengths for the electron impact excitation of S III from the ground 3p2 3P state to the excited states 3s3p3 3D0, 3P0, 3S0, 3d 3D0, 3P0, and 4s 3P0. Also obtained are those transitions' oscillator strengths, and strengths for others involving 3p2 1D and 1S. Configuration-interaction target wave functions yielding oscillator strengths that are accurate to 20 percent are used in collision strength calculations.

  13. Functional capacity, physical activity and muscle strength assessment of individuals with non-small cell lung cancer: a systematic review of instruments and their measurement properties

    PubMed Central

    2013-01-01

    Background The measurement properties of instruments used to assess functional capacity, physical activity and muscle strength in participants with non-small cell lung cancer (NSCLC) have not been systematically reviewed. Method Objectives: To identify outcome measures used to assess these outcomes in participants with NSCLC; and to evaluate, synthesise and compare the measurement properties of the outcome measures identified. Data Sources: A systematic review of articles using electronic databases MEDLINE (1950–2012), CINAHL (1982–2012), EMBASE (1980–2012), Cochrane Library (2012), Expanded Academic ASAP (1994–2012), Health Collection Informit (1995–2012) and PEDRO (1999–2012). Additional studies were identified by searching personal files and cross referencing. Eligibility Criteria for Study Selection: Search one: studies which assessed functional capacity, physical activity or muscle strength in participants with NSCLC using non-laboratory objective tests were included. Search two: studies which evaluated a measurement property (inter- or intra-rater reliability; measurement error; criterion or construct validity; or responsiveness) in NSCLC for one of the outcome measures identified in search one. Studies published in English from 1980 were eligible. Data Extraction and Methodological Quality Assessment: data collection form was developed and data extracted. Methodological quality of studies was assessed by two independent reviewers using the 4-point COSMIN checklist. Results Thirteen outcome measures were identified. Thirty-one studies evaluating measurement properties of the outcome measures in participants with NSCLC were included. Functional capacity was assessed using the six- and twelve-minute walk tests; incremental- and endurance-shuttle walk tests; and the stair-climbing test. Criterion validity for three of these measures was established in NSCLC but not the reliability or responsiveness. Physical activity was measured using accelerometers

  14. Effect of simultaneous application of postural techniques and expiratory muscle strength training on the enhancement of the swallowing function of patients with dysphagia caused by parkinson’s disease

    PubMed Central

    Byeon, Haewon

    2016-01-01

    [Purpose] This study aimed to investigate the effect of simultaneous application of postural techniques and expiratory muscle strength training on the enhancement of the swallowing function of patients with dysphagia caused by Parkinson’s disease. [Subjects and Methods] The subjects of this study were 18 patients who received simultaneous application of postural techniques and expiratory muscle strength training and 15 patients who received expiratory muscle strength training only. Postural techniques were conducted in the order of chin tucking, head rotation, head tilting, bending head back, and lying down, while expiratory muscle strength training was conducted at a resistance level of about 70% of the maximal expiratory pressure. Swallowing recovery was assessed by using the Functional Dysphagia Scale based on videofluoroscopic studies. [Results] The mean value obtained in the videofluoroscopic studies for both groups decreased after the treatment. In the postural techniques plus expiratory muscle strength training group, the decrease was significantly greater than that in the expiratory muscle strength training-only group. [Conclusion] The results imply that simultaneous performance of postural techniques and expiratory muscle strength training is more effective than expiratory muscle strength training alone when applied in the swallowing rehabilitation for patients with dysphagia caused by Parkinson’s disease. PMID:27390429

  15. Beta-decay rate and beta-delayed neutron emission probability of improved gross theory

    NASA Astrophysics Data System (ADS)

    Koura, Hiroyuki

    2014-09-01

    A theoretical study has been carried out on beta-decay rate and beta-delayed neutron emission probability. The gross theory of the beta decay is based on an idea of the sum rule of the beta-decay strength function, and has succeeded in describing beta-decay half-lives of nuclei overall nuclear mass region. The gross theory includes not only the allowed transition as the Fermi and the Gamow-Teller, but also the first-forbidden transition. In this work, some improvements are introduced as the nuclear shell correction on nuclear level densities and the nuclear deformation for nuclear strength functions, those effects were not included in the original gross theory. The shell energy and the nuclear deformation for unmeasured nuclei are adopted from the KTUY nuclear mass formula, which is based on the spherical-basis method. Considering the properties of the integrated Fermi function, we can roughly categorized energy region of excited-state of a daughter nucleus into three regions: a highly-excited energy region, which fully affect a delayed neutron probability, a middle energy region, which is estimated to contribute the decay heat, and a region neighboring the ground-state, which determines the beta-decay rate. Some results will be given in the presentation. A theoretical study has been carried out on beta-decay rate and beta-delayed neutron emission probability. The gross theory of the beta decay is based on an idea of the sum rule of the beta-decay strength function, and has succeeded in describing beta-decay half-lives of nuclei overall nuclear mass region. The gross theory includes not only the allowed transition as the Fermi and the Gamow-Teller, but also the first-forbidden transition. In this work, some improvements are introduced as the nuclear shell correction on nuclear level densities and the nuclear deformation for nuclear strength functions, those effects were not included in the original gross theory. The shell energy and the nuclear deformation for

  16. Is Using the Strengths and Difficulties Questionnaire in a Community Sample the Optimal Way to Assess Mental Health Functioning?

    PubMed Central

    Vaz, Sharmila; Cordier, Reinie; Boyes, Mark; Parsons, Richard; Joosten, Annette; Ciccarelli, Marina; Falkmer, Marita; Falkmer, Torbjorn

    2016-01-01

    An important characteristic of a screening tool is its discriminant ability or the measure’s accuracy to distinguish between those with and without mental health problems. The current study examined the inter-rater agreement and screening concordance of the parent and teacher versions of SDQ at scale, subscale and item-levels, with the view of identifying the items that have the most informant discrepancies; and determining whether the concordance between parent and teacher reports on some items has the potential to influence decision making. Cross-sectional data from parent and teacher reports of the mental health functioning of a community sample of 299 students with and without disabilities from 75 different primary schools in Perth, Western Australia were analysed. The study found that: a) Intraclass correlations between parent and teacher ratings of children’s mental health using the SDQ at person level was fair on individual child level; b) The SDQ only demonstrated clinical utility when there was agreement between teacher and parent reports using the possible or 90% dichotomisation system; and c) Three individual items had positive likelihood ratio scores indicating clinical utility. Of note was the finding that the negative likelihood ratio or likelihood of disregarding the absence of a condition when both parents and teachers rate the item as absent was not significant. Taken together, these findings suggest that the SDQ is not optimised for use in community samples and that further psychometric evaluation of the SDQ in this context is clearly warranted. PMID:26771673

  17. Is Using the Strengths and Difficulties Questionnaire in a Community Sample the Optimal Way to Assess Mental Health Functioning?

    PubMed

    Vaz, Sharmila; Cordier, Reinie; Boyes, Mark; Parsons, Richard; Joosten, Annette; Ciccarelli, Marina; Falkmer, Marita; Falkmer, Torbjorn

    2016-01-01

    An important characteristic of a screening tool is its discriminant ability or the measure's accuracy to distinguish between those with and without mental health problems. The current study examined the inter-rater agreement and screening concordance of the parent and teacher versions of SDQ at scale, subscale and item-levels, with the view of identifying the items that have the most informant discrepancies; and determining whether the concordance between parent and teacher reports on some items has the potential to influence decision making. Cross-sectional data from parent and teacher reports of the mental health functioning of a community sample of 299 students with and without disabilities from 75 different primary schools in Perth, Western Australia were analysed. The study found that: a) Intraclass correlations between parent and teacher ratings of children's mental health using the SDQ at person level was fair on individual child level; b) The SDQ only demonstrated clinical utility when there was agreement between teacher and parent reports using the possible or 90% dichotomisation system; and c) Three individual items had positive likelihood ratio scores indicating clinical utility. Of note was the finding that the negative likelihood ratio or likelihood of disregarding the absence of a condition when both parents and teachers rate the item as absent was not significant. Taken together, these findings suggest that the SDQ is not optimised for use in community samples and that further psychometric evaluation of the SDQ in this context is clearly warranted. PMID:26771673

  18. Using the TIDieR Checklist to Standardize the Description of a Functional Strength Training Intervention for the Upper Limb After Stroke

    PubMed Central

    Hunter, Susan M.; Donaldson, Catherine; Pomeroy, Valerie

    2016-01-01

    Background and Purpose: Published reports of intervention in randomized controlled trials are often poorly described. The Template for Intervention Description and Replication (TIDieR) checklist has been recently developed to improve the reporting of interventions. The aim of this article is to describe a therapy intervention used in the stroke rehabilitation trial, “Clinical Efficacy of Functional Strength Training for Upper Limb Motor Recovery Early After Stroke: Neural Correlates and Prognostic Indicators” (FAST-INdICATE), using TIDieR. Methods: The functional strength training intervention used in the FAST-INdICATE trial was described using TIDieR so that intervention can be replicated by both clinicians, who may implement it in practice, and researchers, who may deliver it in future research. The usefulness of TIDieR in the context of a complex stroke rehabilitation intervention was then discussed. Results and Discussion: The TIDieR checklist provided a systematic way of describing a treatment intervention used in a clinical trial of stroke rehabilitation. Clarification is needed regarding several aspects of the TIDieR checklist, including in which section to report about the development of the intervention in pilot studies, results of feasibility studies; overlap between training and procedures for assessing fidelity; and where to publish supplementary material so that it remains in the public domain. Conclusions: TIDieR is a systematic way of reporting the intervention delivered in a clinical trial of a complex intervention such as stroke rehabilitation. This approach may also have value for standardizing intervention in clinical practice. Video abstract available for more insights from the authors (see Supplemental Digital Content 1, http://links.lww.com/JNPT/A131). PMID:27187925

  19. Relationships of thigh muscle contractile and non-contractile tissue with function, strength, and age in boys with Duchenne muscular dystrophy.

    PubMed

    Akima, Hiroshi; Lott, Donovan; Senesac, Claudia; Deol, Jasjit; Germain, Sean; Arpan, Ishu; Bendixen, Roxanna; Lee Sweeney, H; Walter, Glenn; Vandenborne, Krista

    2012-01-01

    The purpose of this study was to assess the contractile and non-contractile content in thigh muscles of patients with Duchenne muscular dystrophy (DMD) and determine the relationship with functional abilities. Magnetic resonance images of the thigh were acquired in 28 boys with DMD and 10 unaffected boys. Muscle strength, timed functional tests, and the Brookes Lower Extremity scale were also assessed. Non-contractile content in the DMD group was significantly greater than in the control group for six muscles, including rectus femoris, biceps femoris-long head and adductor magnus. Non-contractile content in the total thigh musculature assessed by MRI correlated with the Brookes scale (r(s)=0.75) and supine-up test (r(s)=0.68), as well as other functional measures. An age-related specific torque increase was observed in the control group (r(s)=0.96), but not the DMD (r(s)=0.06). These findings demonstrate that MRI measures of contractile and non-contractile content can provide important information about disease progression in DMD. PMID:21807516

  20. The fracture strength and frictional strength of Weber Sandstone

    USGS Publications Warehouse

    Byerlee, J.D.

    1975-01-01

    The fracture strength and frictional strength of Weber Sandstone have been measured as a function of confining pressure and pore pressure. Both the fracture strength and the frictional strength obey the law of effective stress, that is, the strength is determined not by the confining pressure alone but by the difference between the confining pressure and the pore pressure. The fracture strength of the rock varies by as much as 20 per cent depending on the cement between the grains, but the frictional strength is independent of lithology. Over the range 0 2 kb, ??=0??5 + 0??6??n. This relationship also holds for other rocks such as gabbro, dunite, serpentinite, granite and limestone. ?? 1975.

  1. Gender Differences in Strength.

    ERIC Educational Resources Information Center

    Heyward, Vivian H.; And Others

    1986-01-01

    This investigation examined gender differences of 103 physically active men and women in upper and lower body strength as a function of lean body weight and the distribution of muscle and subcutaneous fat in the upper and lower limbs. Results are discussed. (Author/MT)

  2. Inelastic Scattering and Single and Double Charge Exchange Reactions Within the A=27 Isobaric Multiplet.

    NASA Astrophysics Data System (ADS)

    McKinzie, Matthew Gordon

    1995-01-01

    Angular distributions for the reactions ^{27}Al, ^{28 }Si(pi^{+/- },pi^{+/-} ) at T_pi = 180 MeV and an excitation function at theta_ {rm lab.} = 5^{ rm o} for the reaction ^{27}Al(pi^{+}, pi^{-})^{27}P were measured using the Energetic Pion Channel and Spectrometer at the Clinton P. Anderson Meson Physics Facility in Los Alamos, New Mexico. Angular distributions for the reaction ^{27}Al(n,p)^ {27}Mg were measured at T_ {rm N} = 198 MeV using the Medium Resolution Spectrometer at Canada's Tri-University Meson Facility in Vancouver, British Columbia. Multipole matrix elements were extracted in a macroscopic manner from the pion inelastic angular distributions using the distorted-wave impulse approximation and collective -model transition densities. Microscopic calculations of these extracted matrix elements and of the pion angular distributions were examined. Double charge exchange (DCX) excitation functions to the ^{27}P ground state and an excited state were measured at nine incident pion energies from T_pi = 100 to 293.4 MeV. The systematics of DCX excitation functions to low-lying states is reviewed in light of these data. Microscopic calculations of DCX for and near A = 27 are investigated. Double giant resonances in ^{27}P were observed at the three highest energies. The (n,p) charge exchange angular distributions were obtained for theta_{rm lab.} = 0^circ, 4^circ, 8^ circ, 12^circ, 18^circ and 24^ circ. The Gamow-Teller strength distribution was measured and compared to a microscopic calculation. The constant of proportionality between reduced transition probability and cross section (the unit cross section) was generalized and examined for configuration dependence. Data for higher spin-multipole isovector excitations are presented, including low-lying spin-isospin E2 strength and negative -parity giant resonances.

  3. Isokinetic quadriceps and hamstring muscle strength and knee function 5 years after anterior cruciate ligament reconstruction: comparison between bone-patellar tendon-bone and hamstring tendon autografts.

    PubMed

    Lautamies, Riitta; Harilainen, Arsi; Kettunen, Jyrki; Sandelin, Jerker; Kujala, Urho M

    2008-11-01

    Existing clinical studies have not proven which graft is to be preferred in anterior cruciate ligament (ACL) reconstruction. In recent years, bone-patellar tendon-bone and hamstring tendons have been the most frequently used graft types. Muscle strength deficit is one of the consequences after ACL reconstruction. The aim of this study was to evaluate possible differences in hamstring and quadriceps muscle strength and knee function 5 years after ACL reconstruction between the BPTB and the STG groups. The study group consisted of 288 patients (132 women, 156 men) with a unilateral ACL rupture who had received a BPTB (175 patients) or STG (113 patients) ACL reconstruction. Lower extremity concentric isokinetic peak extension and flexion torques were assessed at the angular velocities of 60 degrees /s and 180 degrees /s. The International Knee Documentation Committee (IKDC), the Tegner activity level, the Lysholm knee and the Kujala patellofemoral scores were also collected. Isokinetic quadriceps peak torque (percentage of the contralateral side) was 3.9% higher in the STG group than in the BPTB group at the velocity of 60 degrees /s and 3.2% higher at the velocity of 180 degrees /s and the isokinetic hamstring peak torque 2% higher in the BPTB group than in the STG group at the velocity of 60 degrees /s and 2.5% higher at the velocity of 180 degrees /s. In both groups the subjects had weaker quadriceps and hamstring muscle strength in the injured extremity compared with the uninjured one. In the single-leg hop test (according to the IKDC recommendations) there was a statistically significant difference (P = 0.040) between the groups. In the STG group, 68% of the patients had the single-leg hop ratio (injured vs. uninjured extremity) > or =90%, 31% of the patients 75-89% and 1% of the patients <75%, while in the BPTB group the corresponding percentages were 72, 21 and 7%. However, no statistically significant differences in clinical outcome were found between the

  4. Three-Dimensional Gait Analysis Following Achilles Tendon Rupture With Nonsurgical Treatment Reveals Long-Term Deficiencies in Muscle Strength and Function

    PubMed Central

    Tengman, Tine; Riad, Jacques

    2013-01-01

    Background: Precise long-term assessment of movement and physical function following Achilles tendon rupture is required for the development and evaluation of treatment, including different regimens of physical therapy. Purpose: To assess intermediate-term (<10 years by conventional thinking) objective measures of physical function following Achilles tendon rupture treated nonsurgically and to compare these with self-reported measures of physical function. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Two to 5 years after Achilles tendon rupture, 9 women and 43 men (mean age, 49.2 years; range, 26-68 years) were assessed by physical examination, performance of 1-legged jumps, and 3-dimensional gait analysis (including calculation of muscle work). Self-reported scores for foot function (Achilles tendon rupture score) and level of physical activity were collected. Twenty age- and sex-matched controls were assessed in the same manner. Results: Physical examination of patients with the knee extended revealed 11.1° of dorsiflexion on the injured side and 9.2° on the uninjured side (P = .020), indicating gastrocnemius muscle lengthening. The 1-legged jump distance was shorter on the injured side (89.5 vs 96.2 cm; P < .001). Gait analysis showed higher peak dorsiflexion (14.3° vs 13.3°; P = .016) and lower concentric (positive) plantar flexor work (16.6 vs 19.9 J/kg; P = .001) in the ankle on the uninjured side. At the same time, eccentric (negative) dorsiflexor work was higher on the injured side (13.2 vs 11.9 J/kg; P = .010). Self-perceived foot function and physical activity were lower in patients than in healthy controls (mean Achilles tendon rupture score, 78.6 and 99.8, respectively). Conclusion: Nonsurgically treated patients with Achilles tendon rupture showed signs of both anatomic and functional lengthening of the tendon. Attenuated muscle strength and function were present during walking as long as 2 to 5 years after rupture, as

  5. FAST CP: protocol of a randomised controlled trial of the efficacy of a 12-week combined Functional Anaerobic and Strength Training programme on muscle properties and mechanical gait deficiencies in adolescents and young adults with spastic-type cerebral palsy

    PubMed Central

    Gillett, Jarred G; Lichtwark, Glen A; Boyd, Roslyn N; Barber, Lee A

    2015-01-01

    Introduction Individuals with cerebral palsy (CP) have muscles that are smaller, weaker and more resistant to stretch compared to typically developing people. Progressive resistance training leads to increases in muscle size and strength. In CP, the benefits of resistance training alone may not transfer to improve other activities such as walking; however, the transfer of strength improvements to improved mobility may be enhanced by performing training that involves specific functional tasks or motor skills. This study aims to determine the efficacy of combined functional anaerobic and strength training in (1) influencing muscle strength, structure and function and (2) to determine if any changes in muscle strength and structure following training impact on walking ability and gross motor functional capacity and performance in the short (following 3 months of training) and medium terms (a further 3 months post-training). Methods and analysis 40 adolescents and young adults with CP will be recruited to undertake a 12-week training programme. The training programme will consist of 3×75 min sessions per week, made up of 5 lower limb resistance exercises and 2–3 functional anaerobic exercises per session. The calf muscles will be specifically targeted, as they are the most commonly impacted muscles in CP and are a key muscle group involved in walking. If, as we believe, muscle properties change following combined strength and functional training, there may be long-term benefits of this type of training in slowing the deterioration of muscle function in people with spastic-type CP. Ethics and dissemination Ethical approval has been obtained from the ethics committees at The University of Queensland (2014000066) and Children's Health Queensland (HREC/15/QRCH/30). The findings will be disseminated by publications in peer-reviewed journals, conferences and local research organisations’ media. Trial registration number Australian and New Zealand Clinical Trials

  6. The effect of neuromuscular electrical stimulation on quadriceps strength and knee function in professional soccer players: return to sport after ACL reconstruction.

    PubMed

    Taradaj, J; Halski, T; Kucharzewski, M; Walewicz, K; Smykla, A; Ozon, M; Slupska, L; Dymarek, R; Ptaszkowski, K; Rajfur, J; Pasternok, M

    2013-01-01

    The aim of this study was to assess the clinical efficacy and safety of NMES program applied in male soccer players (after ACL reconstruction) on the quadriceps muscle. The 80 participants (NMES = 40, control = 40) received an exercise program, including three sessions weekly. The individuals in NMES group additionally received neuromuscular electrical stimulation procedures on both right and left quadriceps (biphasic symmetric rectangular pulses, frequency of impulses: 2500 Hz, and train of pulses frequency: 50 Hz) three times daily (3 hours of break between treatments), 3 days a week, for one month. The tensometry, muscle circumference, and goniometry pendulum test (follow-up after 1 and 3 months) were applied. The results of this study show that NMES (in presented parameters in experiment) is useful for strengthening the quadriceps muscle in soccer athletes. There is an evidence of the benefit of the NMES in restoring quadriceps muscle mass and strength of soccer players. In our study the neuromuscular electrical stimulation appeared to be safe for biomechanics of knee joint. The pathological changes in knee function were not observed. This trial is registered with Australian and New Zealand Clinical Trials Registry ACTRN12613001168741.

  7. Effect of the tongue rotation exercise training on the oral functions in normal adults - Part 1 investigation of tongue pressure and labial closure strength.

    PubMed

    Arakawa, I; Koide, K; Takahashi, M; Mizuhashi, F

    2015-06-01

    The aim of this study was to investigate the effect of the tongue rotation exercise training on the oral functions using the measurement of maximum tongue pressure (MTP) and labial closure strength (LCS) in normal adults. In experiment 1, the differences in MTP and LCS at the measurement point for both groups with and without tongue rotation exercise training were examined. We instructed subjects to perform the tongue rotation exercise for 2 months. We measured MTP and LCS at the point before training and at the points of 1 and 2 months after the beginning of training. In experiment 2, the changes of MTP and LCS based on the sex differences and the measurement points in training were examined. We instructed subjects to perform the tongue rotation exercise for 3 months, and measured MTP and LCS at the point before training and at the points of 2 weeks and 1, 2 and 3 months after the beginning of training. The results of experiment 1 showed MTP and LCS increased with the progress of continuous training. The results of experiment 2 showed MTP and LCS were always higher in men than in women and increased significantly at 2 weeks of training in both sexes (P < 0.01). These results might be suggested that the tongue rotation exercise training was effective for the recovery of the activity of the stomatognathic system.

  8. The Effect of NeuroMuscular Electrical Stimulation on Quadriceps Strength and Knee Function in Professional Soccer Players: Return to Sport after ACL Reconstruction

    PubMed Central

    Taradaj, J.; Halski, T.; Kucharzewski, M.; Walewicz, K.; Smykla, A.; Ozon, M.; Slupska, L.; Dymarek, R.; Ptaszkowski, K.; Rajfur, J.; Pasternok, M.

    2013-01-01

    The aim of this study was to assess the clinical efficacy and safety of NMES program applied in male soccer players (after ACL reconstruction) on the quadriceps muscle. The 80 participants (NMES = 40, control = 40) received an exercise program, including three sessions weekly. The individuals in NMES group additionally received neuromuscular electrical stimulation procedures on both right and left quadriceps (biphasic symmetric rectangular pulses, frequency of impulses: 2500 Hz, and train of pulses frequency: 50 Hz) three times daily (3 hours of break between treatments), 3 days a week, for one month. The tensometry, muscle circumference, and goniometry pendulum test (follow-up after 1 and 3 months) were applied. The results of this study show that NMES (in presented parameters in experiment) is useful for strengthening the quadriceps muscle in soccer athletes. There is an evidence of the benefit of the NMES in restoring quadriceps muscle mass and strength of soccer players. In our study the neuromuscular electrical stimulation appeared to be safe for biomechanics of knee joint. The pathological changes in knee function were not observed. This trial is registered with Australian and New Zealand Clinical Trials Registry ACTRN12613001168741. PMID:24381943

  9. Characterizing the Long-Term PM2.5 Concentration-Response Function: Comparing the Strengths and Weaknesses of Research Synthesis Approaches.

    PubMed

    Fann, Neal; Gilmore, Elisabeth A; Walker, Katherine

    2016-09-01

    The magnitude, shape, and degree of certainty in the association between long-term population exposure to ambient fine particulate matter (PM2.5 ) and the risk of premature death is one of the most intensely studied issues in environmental health. For regulatory risk analysis, this relationship is described quantitatively by a concentration-response (C-R) function that relates exposure to ambient concentrations with the risk of premature mortality. Four data synthesis techniques develop the basis for, and derive, this function: systematic review, expert judgment elicitation, quantitative meta-analysis, and integrated exposure-response (IER) assessment. As part of an academic workshop aiming to guide the use of research synthesis approaches, we developed criteria with which to evaluate and select among the approaches for their ability to inform policy choices. These criteria include the quality and extent of scientific support for the method, its transparency and verifiability, its suitability to the policy problem, and the time and resources required for its application. We find that these research methods are both complementary and interdependent. A systematic review of the multidisciplinary evidence is a starting point for all methods, providing the broad conceptual basis for the nature, plausibility, and strength of the associations between PM exposure and adverse health effects. Further, for a data-rich application like PM2.5 and premature mortality, all three quantitative approaches can produce estimates that are suitable for regulatory and benefit analysis. However, when fewer data are available, more resource-intensive approaches such as expert elicitation may be more important for understanding what scientists know, where they agree or disagree, and what they believe to be the most important areas of uncertainty. Whether implicitly or explicitly, all require considerable judgment by scientists. Finding ways for all these methods to acknowledge

  10. Opposite Phenotypes of Muscle Strength and Locomotor Function in Mouse Models of Partial Trisomy and Monosomy 21 for the Proximal Hspa13-App Region

    PubMed Central

    Brault, Véronique; Duchon, Arnaud; Romestaing, Caroline; Sahun, Ignasi; Pothion, Stéphanie; Karout, Mona; Borel, Christelle; Dembele, Doulaye; Bizot, Jean-Charles; Messaddeq, Nadia; Sharp, Andrew J.; Roussel, Damien; Antonarakis, Stylianos E; Dierssen, Mara; Hérault, Yann

    2015-01-01

    The trisomy of human chromosome 21 (Hsa21), which causes Down syndrome (DS), is the most common viable human aneuploidy. In contrast to trisomy, the complete monosomy (M21) of Hsa21 is lethal, and only partial monosomy or mosaic monosomy of Hsa21 is seen. Both conditions lead to variable physiological abnormalities with constant intellectual disability, locomotor deficits, and altered muscle tone. To search for dosage-sensitive genes involved in DS and M21 phenotypes, we created two new mouse models: the Ts3Yah carrying a tandem duplication and the Ms3Yah carrying a deletion of the Hspa13-App interval syntenic with 21q11.2-q21.3. Here we report that the trisomy and the monosomy of this region alter locomotion, muscle strength, mass, and energetic balance. The expression profiling of skeletal muscles revealed global changes in the regulation of genes implicated in energetic metabolism, mitochondrial activity, and biogenesis. These genes are downregulated in Ts3Yah mice and upregulated in Ms3Yah mice. The shift in skeletal muscle metabolism correlates with a change in mitochondrial proliferation without an alteration in the respiratory function. However, the reactive oxygen species (ROS) production from mitochondrial complex I decreased in Ms3Yah mice, while the membrane permeability of Ts3Yah mitochondria slightly increased. Thus, we demonstrated how the Hspa13-App interval controls metabolic and mitochondrial phenotypes in muscles certainly as a consequence of change in dose of Gabpa, Nrip1, and Atp5j. Our results indicate that the copy number variation in the Hspa13-App region has a peripheral impact on locomotor activity by altering muscle function. PMID:25803843

  11. Opposite phenotypes of muscle strength and locomotor function in mouse models of partial trisomy and monosomy 21 for the proximal Hspa13-App region.

    PubMed

    Brault, Véronique; Duchon, Arnaud; Romestaing, Caroline; Sahun, Ignasi; Pothion, Stéphanie; Karout, Mona; Borel, Christelle; Dembele, Doulaye; Bizot, Jean-Charles; Messaddeq, Nadia; Sharp, Andrew J; Roussel, Damien; Antonarakis, Stylianos E; Dierssen, Mara; Hérault, Yann

    2015-03-01

    The trisomy of human chromosome 21 (Hsa21), which causes Down syndrome (DS), is the most common viable human aneuploidy. In contrast to trisomy, the complete monosomy (M21) of Hsa21 is lethal, and only partial monosomy or mosaic monosomy of Hsa21 is seen. Both conditions lead to variable physiological abnormalities with constant intellectual disability, locomotor deficits, and altered muscle tone. To search for dosage-sensitive genes involved in DS and M21 phenotypes, we created two new mouse models: the Ts3Yah carrying a tandem duplication and the Ms3Yah carrying a deletion of the Hspa13-App interval syntenic with 21q11.2-q21.3. Here we report that the trisomy and the monosomy of this region alter locomotion, muscle strength, mass, and energetic balance. The expression profiling of skeletal muscles revealed global changes in the regulation of genes implicated in energetic metabolism, mitochondrial activity, and biogenesis. These genes are downregulated in Ts3Yah mice and upregulated in Ms3Yah mice. The shift in skeletal muscle metabolism correlates with a change in mitochondrial proliferation without an alteration in the respiratory function. However, the reactive oxygen species (ROS) production from mitochondrial complex I decreased in Ms3Yah mice, while the membrane permeability of Ts3Yah mitochondria slightly increased. Thus, we demonstrated how the Hspa13-App interval controls metabolic and mitochondrial phenotypes in muscles certainly as a consequence of change in dose of Gabpa, Nrip1, and Atp5j. Our results indicate that the copy number variation in the Hspa13-App region has a peripheral impact on locomotor activity by altering muscle function.

  12. The evolution of granule fracture strength as a function of impeller tip speed and granule size for a novel reverse-phase wet granulation process.

    PubMed

    Wade, J B; Martin, G P; Long, D F

    2015-07-01

    The feasibility of a novel reverse-phase wet granulation process has been established previously and several potential advantages over the conventional process have been highlighted (Wade et al., 2014a,b,b). Due to fundamental differences in the growth mechanism and granule consolidation behaviour between the two processes the reverse-phase approach generally formed granules with a greater mass mean diameter and a lower intragranular porosity than those formed by the conventional granulation process under the same liquid saturation and impeller tip speed conditions. The lower intragranular porosity was hypothesised to result in an increase in the granule strength and subsequent decrease in tablet tensile strength. Consequently, the aim of this study was to compare the effect of impeller tip speed and granule size on the strength and compaction properties of granules prepared using both the reverse-phase and conventional granulation processes. For the conventional granulation process an increase in the impeller tip speed from 1.57 to 4.71 ms(-1) (200-600 RPM) resulted in an increase in the mean granule strength (p<0.05) for all granule size fractions and as the granule size fraction increased from 425-600 to 2000-3350 μm the mean fracture strength decreased (p<0.05). For the reverse-phase process an increase in impeller tip speed had no effect (p>0.05) on mean granule strength whereas, like the conventional process, an increase in granule size fraction from 425-600 to 2000-3350 μm resulted in a decrease (p<0.05) in the mean fracture strength. No correlation was found between mean granule fracture strength and the tablet tensile strength (p>0.05) for either granulation approach. These data support the rejection of the original hypothesis which stated that an increase in granule strength may result in a decrease in the tablet tensile strength. The similar tablet tensile strength observed between the conventional and reverse-phase granulation processes indicated that

  13. Neutrino mean free paths in cold symmetric nuclear matter

    SciTech Connect

    Cowell, S.; Pandharipande, V.R.

    2004-09-01

    The neutrino mean free paths (NMFP) for scattering and absorption in cold symmetric nuclear matter (SNM) are calculated using two-body effective interactions and one-body effective weak operators obtained from realistic models of nuclear forces using correlated basis theory. The infinite system is modeled in a box with periodic boundary conditions and the one particle-hole (p-h) response functions are calculated using the Tamm-Dancoff approximation (TDA). For the densities {rho}=(1/2), 1 (3/2){rho}{sub 0}, where {rho}{sub 0} is the equilibrium density of SNM, the strength of the response is shifted to higher energy transfers when compared to a noninteracting Fermi gas (FG). This and the weakness of effective operators compared to the bare operators, significantly reduces the cross sections, enhancing the NMFP by factors of {approx}2.5-3.5 at the densities considered. The NMFP at the equilibrium density {rho}{sub 0} are also calculated using the TDA and random phase approximation (RPA) using zero range Skyrme-like effective interactions with parameters chosen to reproduce the equation of state and spin-isospin susceptibilities of matter. Their results indicate that RPA corrections to correlated TDA may further increase the NMFP by {approx}25% to 3-4 times those in a noninteracting FG. Finally, the sums and the energy weighted sums of the Fermi and Gamow-Teller responses obtained from the correlated ground state are compared with those of the 1 p-h response functions to extract the sum and mean energies of multi p-h contributions to the weak response. The relatively large mean energy of the multi p-h excitations suggests that they may not contribute significantly to low energy NMFP.

  14. Beta-decay rates

    NASA Astrophysics Data System (ADS)

    Borzov, I. N.

    2006-10-01

    Major astrophysical applications involve a huge number of exotic nuclei. Their beta-decay properties play a crucial role in stellar explosive events. An important effort has been developed in last decades to measure the masses and β-decay properties of very neutron-rich nuclei at radioactive nuclear beam facilities. However, most of them cannot be synthesized in terrestrial laboratories and only theoretical predictions can fill the gap. We will concentrate mainly on the β-decay rates needed for stellar r-process modeling and for performing the RNB experiments. An overview of the microscopic approaches to the β-decay strength function is given. The continuum QRPA approach based on the self-consistent ground state description in the framework of the density functional theory is outlined. For the first time, a systematic study of the total β-decay half-lives and delayed neutron emission probabilities takes into account the Gamow Teller and first-forbidden transitions. Due to the shell configuration effects, the first-forbidden decays have a strong impact on the β-decay characteristics of the r-process relevant nuclei at Z≈28, N>50; Z⩾50, N>82 and Z=60 70, N≈126. Suppression of the delayed neutron emission probability is found in nuclei with the neutron excess bigger than one major shell. The effect originates from the high-energy first-forbidden transitions to the states outside the (Q-B)-window in the daughter nuclei. The performance of existing global models for the nuclides near the r-process paths is critically analyzed and confronted with the recent RIB experiments in the regions of 78Ni, 132Sn and “east” of 208Pb.

  15. Muon capture on deuteron and 3He

    SciTech Connect

    Marcucci, L. E.; Piarulli, M.; Viviani, M.; Girlanda, L.; Kievsky, A.; Rosati, S.; Schiavilla, R.

    2011-01-01

    The muon capture reactions 2H(μ-, vμ)nn and 3He(μ-, vμ)3H are studied with realistic or chiral potentials and consistent weak currents. The initial and final A = 2 and 3 nuclear wave functions are obtained from the Argonne v18 (AV18) or chiral N3LO (N3LO) two-nucleon potential, in combination with, respectively, the Urbana IX (UIX) or chiral N2LO (N2LO) three-nucleon potential in the case of A = 3. The weak current consists of polar- and axial-vector components. The former are related to the isovector piece of the electromagnetic current via the conserved-vector-current hypothesis. These and the axial currents are derived either in a meson-exchange or in a chiral effective field theory ( EFT) framework. There is one parameter (either the N-to-Delta axial coupling constant in the meson-exchange model, or the strength of a contact term in the EFT model) which is fixed by reproducing the Gamow-Teller matrix element in tritium-decay. The model dependence relative to the adopted interactions and currents (and cutoff sensitivity in the EFT currents) is weak, resulting in total rates of 392.0 ± 2.3 s-1 for A = 2, and 1484 ± 13 s-1 for A = 3, where the spread accounts for this model dependence.

  16. Solubility of B-Nb2O5 and the Hydrolysis of Niobium(V) in Aqueous Solution as a Function of Temperature and Ionic Strength

    SciTech Connect

    Peiffert, C; Nguyen-Trung, Chinh {nmn}; Palmer, Donald; Laval, J. P.; Giffaut, E.

    2010-01-01

    B-Nb{sub 2}O{sub 5} was recrystallized from commercially available oxide, and XRD analyses indicated that it is stable in contact with solutions over the pH range 0 to 9, whereas solid polyniobates such as Na{sub 8}Nb{sub 6}O{sub 19} 13H{sub 2}O(s) appear to predominate at pH > 9. Solubilities of the crystalline B-Nb{sub 2}O{sub 5} were determined in five NaClO{sub 4} solutions (0.1 {le} Im/mol {center_dot} kg{sup -1} {le} 1.0) over a wide pH range at (25.0 {+-} 0.1) C and at 0.1 MPa. A limited number of measurements were also made at Im = 6.0 mol {center_dot} kg{sup -1}, whereas at Im = 1.0 mol {center_dot} kg{sup -1} the full range of pH was also covered at (10, 50 and 70) C. The pH of these solutions was fixed using either HClO{sub 4} (pH {le} 4) or NaOH (pH {ge} 10) and determined by mass balance, whereas the pH on the molality scale was measured in buffer mixtures of acetic acid + acetate (4 {le} pH {le} 6), Bis-Tris (pH {approx} 7), Tris (pH {approx} 8) and boric acid + borate (pH {approx} 9). Treatment of the solubility results indicated the presence of four species, Nb(OH){sub n}{sup 5-n} (where n = 4-7), so that the molal solubility quotients were determined according to: 0.5Nb{sub 2}O{sub 5}(cr) + 0.5(2n-5)H{sub 2}O(l){sup {center_dot}-} Nb(OH){sub n}{sup 5-n} + (n-5)H{sup +} (n = 4-7) and were fitted empirically as a function of ionic strength and temperature, including the appropriate Debye-Hueckel term. A Specific Interaction Theory (SIT) approach was also attempted. The former approach yielded the following values of log 10 K{sub sn} (infinite dilution) at 25 C: -(7.4 {+-} 0.2) for n = 4; -(9.1 {+-} 0.1) for n = 5; -(14.1 {+-} 0.3) for n = 6; and -(23.9 {+-} 0.6) for n = 7. Given the experimental uncertainties (2{sigma}), it is interesting to note that the effect of ionic strength only exceeded the combined uncertainties significantly in the case of log 10 K{sub s6} to I{sub m} = 1.0 mol {center_dot} kg{sup -1}, such that these values may be of use by

  17. Application of Strength Diagnosis.

    ERIC Educational Resources Information Center

    Newton, Robert U.; Dugan, Eric

    2002-01-01

    Discusses the various strength qualities (maximum strength, high- and low-load speed strength, reactive strength, rate of force development, and skill performance), noting why a training program design based on strength diagnosis can lead to greater efficacy and better performance gains for the athlete. Examples of tests used to assess strength…

  18. Distraction Effects of Smoking Cues in Antismoking Messages: Examining Resource Allocation to Message Processing as a Function of Smoking Cues and Argument Strength

    PubMed Central

    Lee, Sungkyoung; Cappella, Joseph N.

    2014-01-01

    Findings from previous studies on smoking cues and argument strength in antismoking messages have shown that the presence of smoking cues undermines the persuasiveness of antismoking public service announcements (PSAs) with weak arguments. This study conceptualized smoking cues (i.e., scenes showing smoking-related objects and behaviors) as stimuli motivationally relevant to the former smoker population and examined how smoking cues influence former smokers’ processing of antismoking PSAs. Specifically, by defining smoking cues and the strength of antismoking arguments in terms of resource allocation, this study examined former smokers’ recognition accuracy, memory strength, and memory judgment of visual (i.e., scenes excluding smoking cues) and audio information from antismoking PSAs. In line with previous findings, the results of the study showed that the presence of smoking cues undermined former smokers’ encoding of antismoking arguments, which includes the visual and audio information that compose the main content of antismoking messages. PMID:25477766

  19. Oscillator strengths and collision strengths for S v

    NASA Technical Reports Server (NTRS)

    Van Wyngaarden, W. L.; Henry, R. J. W.

    1981-01-01

    Observations of the optical extreme-ultraviolet spectrum of the Jupiter planetary system during the Voyager space mission revealed bright emission lines of some sulfur ions. The spectra of the torus at the orbit of Io are likely to contain S V lines. The described investigation provides oscillator strengths and collision strengths for the first four UV lines. The collision strengths from the ground state to four other excited states are also obtained. Use is made of a two-state calculation which is checked for convergence for some transitions by employing a three-state or a four-state approximation. Target wave functions for S V are calculated so that the oscillator strengths calculated in dipole length and dipole velocity approximations agree within 5%.

  20. β-decay properties of neutron-deficient Pt, Hg, and Pb isotopes

    SciTech Connect

    Sarriguren, P.; Boillos, J. M.; Moreno, O.; Moya de Guerra, E.

    2015-10-15

    Neutron-deficient isotopes in the lead region are well established examples of the shape coexistence phenomenon in nuclei. In this work, bulk and decay properties, including deformation energy curves, charge mean square radii, Gamow-Teller (GT) strength distributions, and β-decay half-lives, are studied in neutron-deficient Pt, Hg, and Pb isotopes. The nuclear structure involved is described microscopically from deformed quasiparticle random-phase approximation calculations with residual interactions in both particle-hole and particle-particle channels, performed on top of a self-consistent deformed quasiparticle Skyrme Hartree-Fock basis. The sensitivity to deformation of the GT strength distributions in those isotopes is proposed as an additional complementary signature of the nuclear shape. The β-decay half-lives resulting from the GT strength distributions are compared to experiment to demonstrate the ability of the method.

  1. Lower extremity extension force and electromyography properties as a function of knee angle and their relation to joint torques: implications for strength diagnostics.

    PubMed

    Hahn, Daniel

    2011-06-01

    The purpose of this study was to evaluate whether and how isometric multijoint leg extension strength can be used to assess athletes' muscular capability within the scope of strength diagnosis. External reaction forces (Fext) and kinematics were measured (n = 18) during maximal isometric contractions in a seated leg press at 8 distinct joint angle configurations ranging from 30 to 100° knee flexion. In addition, muscle activation of rectus femoris, vastus medialis, biceps femoris c.l., gastrocnemius medialis, and tibialis anterior was obtained using surface electromyography (EMG). Joint torques for hip, knee, and ankle joints were computed by inverse dynamics. The results showed that unilateral Fext decreased significantly from 3,369 ± 575 N at 30° knee flexion to 1,015 ± 152 N at 100° knee flexion. Despite maximum voluntary effort, excitation of all muscles as measured by EMG root mean square changed with knee flexion angles. Moreover, correlations showed that above-average Fext at low knee flexion is not necessarily associated with above-average Fext at great knee flexion and vice versa. Similarly, it is not possible to deduce high joint torques from high Fext just as above-average joint torques in 1 joint do not signify above-average torques in another joint. From these findings, it is concluded that an evaluation of muscular capability by means of Fext as measured for multijoint leg extension is strongly limited. As practical recommendation, we suggest analyzing multijoint leg extension strength at 3 distinct knee flexion angles or at discipline-specific joint angles. In addition, a careful evaluation of muscular capacity based on measured Fext can be done for knee flexion angles ≥ 80°. For further and detailed analysis of single muscle groups, the use of inverse dynamic modeling is recommended.

  2. β -decay properties of neutron-rich Ge, Se, Kr, Sr, Ru, and Pd isotopes from deformed quasiparticle random-phase approximation

    NASA Astrophysics Data System (ADS)

    Sarriguren, P.

    2015-04-01

    β -decay properties of even- and odd-A neutron-rich Ge, Se, Kr, Sr, Ru, and Pd isotopes involved in the astrophysical rapid neutron capture process are studied within a deformed proton-neutron quasiparticle random-phase approximation. The underlying mean field is described self-consistently from deformed Skyrme-Hartree-Fock calculations with pairing correlations. Residual interactions in the particle-hole and particle-particle channels are also included in the formalism. The isotopic evolution of the various nuclear equilibrium shapes and the corresponding charge radii are investigated in all the isotopic chains. The energy distributions of the Gamow-Teller strength as well as the β -decay half-lives are discussed and compared with the available experimental information. It is shown that nuclear deformation plays a significant role in the description of the decay properties in this mass region. Reliable predictions of the strength distributions are essential to evaluate decay rates in astrophysical scenarios.

  3. The (d,2He) reaction on Se76 and the double-β-decay matrix elements for A=76

    NASA Astrophysics Data System (ADS)

    Grewe, E.-W.; Bäumer, C.; Dohmann, H.; Frekers, D.; Harakeh, M. N.; Hollstein, S.; Johansson, H.; Popescu, L.; Rakers, S.; Savran, D.; Simon, H.; Thies, J. H.; van den Berg, A. M.; Wörtche, H. J.; Zilges, A.

    2008-10-01

    The (d,2He) charge-exchange reaction on Se76 was studied at an incident energy of 183 MeV. The outgoing two protons in the 1S0 state, referred to as He2, were both momentum analyzed and detected by the same spectrometer and detector. The experiment was performed at KVI, Groningen, using the magnetic spectrometer BBS at three angular positions: 0°,2.5°, and 5°. Excitation-energy spectra of the residual nucleus As76 were obtained with an energy resolution of about 120 keV (FWHM). Gamow-Teller (GT+) transition strengths were extracted up to 5 MeV and compared with those from an (n,p) experiment at low resolution. Together with the GT- transition strengths from the 76Ge(p,n) experiment leading to the same intermediate nucleus, the nuclear matrix element of the two-neutrino double-β decay of Ge76 was evaluated.

  4. Beta-decay properties of neutron-rich medium-mass nuclei

    NASA Astrophysics Data System (ADS)

    Sarriguren, Pedro

    2016-06-01

    β-decay properties of even-even and odd-A neutron-rich Ge, Se, Kr, Sr, Zr, Mo, Ru, and Pd isotopes involved in the astrophysical rapid neutron capture process are studied within a microscopic proton-neutron quasiparticle random-phase approximation. The underlying mean field is based on a self-consistent Skyrme Hartree-Fock + BCS calculation that includes deformation as a key ingredient. The isotopic evolution of the various nuclear equilibrium shapes and the corresponding charge radii are investigated in all the isotopic chains. The energy distributions of the Gamow-Teller strength, as well as the β-decay half-lives are discussed and compared with the available experimental information. It is shown that nuclear deformation plays a significant role in the description of the decay properties in this mass region. Reliable predictions of the strength distributions are essential to evaluate decay rates in astrophysical scenarios.

  5. Electron Capture Reactions and Beta Decays in Steller Environments

    SciTech Connect

    Suzuki, T.; Mao, H.; Honma, M.; Yoshida, T.; Kajino, T.; Otsuka, T.

    2011-10-28

    Electron capture reactions on Ni and Co isotopes are investigated by shell model calculations in steller environments. The capture rates depend sensitively on the distribution of the Gamow-Teller (GT) strength. The capture rates obtained by using GXPF1J Hamiltonian for fp-shell are found to be consistent with the rates obtained from experimental GT strength in {sup 58}Ni and {sup 60}Ni. Capture rates in Co isotopes, where there were large discrepancies among previous calculations, are also investigated. Beta decays of the N = 126 isotones are studied by shell model calculations taking into account both the GT and first-forbidden (FF) transitions. The FF transitions are found to be important to reduce the half-lives by twice to several times of those by the GT contributions only. Implications of the short half-lives of the waiting point nuclei on the r-process nucleosynthesis are discussed for various astrophysical conditions.

  6. Neutrino absorption by hot nuclei in supernova environments

    NASA Astrophysics Data System (ADS)

    Dzhioev, Alan A.; Vdovin, A. I.; Wambach, J.

    2015-10-01

    Using the thermal quasiparticle random-phase approximation, we study the process of neutrino and antineutrino capture on hot nuclei in supernova environments. For the sample nuclei 56Fe and 82Ge we perform a detailed analysis of thermal effects on the strength distribution of allowed Gamow-Teller (GT) transitions which dominate low-energy charged-current neutrino reactions. The finite-temperature cross sections are calculated taking into account the contributions of both allowed and forbidden transitions. The enhancement of the low-energy cross sections is explained by considering thermal effects on the GT± strength. For 56Fe we compare the calculated finite-temperature cross sections with those obtained from large-scale shell-model calculations.

  7. Flexibility and Muscular Strength.

    ERIC Educational Resources Information Center

    Liemohn, Wendell

    1988-01-01

    This definition of flexibility and muscular strength also explores their roles in overall physical fitness and focuses on how increased flexibility and muscular strength can help decrease or eliminate lower back pain. (CB)

  8. "a" interfacial parameter in Nicolais-Narkis model for yield strength of polymer particulate nanocomposites as a function of material and interphase properties.

    PubMed

    Zare, Yasser

    2016-05-15

    In this paper, "a" interfacial parameter in Nicolais-Narkis model is expressed by thickness "ri" and strength "σi" of interphase between polymer and nanoparticles as well as material properties. "a" parameter is connected to "B1" interfacial parameter in modified Pukanszky model and the effects of "ri" and "σi" on "a" are explained. The negligible difference between "a" values calculated by fitting the experimental results to Nicolais-Narkis model and also, by "B1" results confirms the accurateness of the suggested relation between "a" and "B1" parameters. Additionally, an inverse relation is found between "a" and "B1" parameters for nanocomposites containing spherical nanoparticles. The results demonstrate that the slight levels of "ri" and "σi" data give a large value of "a" which indicates the poor interfacial adhesion.

  9. Exquisite 1D Assemblies Arising from Rationally Designed Asymmetric Donor-Acceptor Architectures Exhibiting Aggregation-Induced Emission as a Function of Auxiliary Acceptor Strength.

    PubMed

    Singh, Roop Shikha; Mukhopadhyay, Sujay; Biswas, Arnab; Pandey, Daya Shankar

    2016-01-11

    One-dimensional nanostructures with aggregation-induced emission (AIE) properties have been fabricated to keep the pace with growing demand from optoelectronics applications. The compounds 2-[4-(4-methylpiperazin-1-yl)benzylidene]malononitrile (PM1), 2-{4-[4-(pyridin-2-yl)piperazin-1-yl]-benzylidene}malononitrile (PM2), and 2-{4-[4-(pyrimidin-2-yl)piperazin-1-yl]benzylidene}malononitrile (PM3) have been designed and synthesized by melding piperazine and dicyanovinylene to investigate AIE in an asymmetric donor-acceptor (D-A) construct of A'-D-π-A- topology. The synthetic route has been simplified by using phenylpiperazine as a weak donor (D), dicyanovinylene as an acceptor (A), and pyridyl/pyrimidyl groups (PM2/PM3) as auxiliary acceptors (A'). It has been established that A' plays a vital role in triggering AIE in these compounds because the same D-A construct led to aggregation-caused quenching upon replacing A' with an electron-donating ethyl group (PM1). Moreover, the effect of restricted intramolecular rotation and twisted intramolecular charge transfer on the mechanism of AIE has also been investigated. Furthermore, it has been clearly shown that the optical disparities of these A'-D-π-A architectures are a direct consequence of comparative A' strength. Single-crystal X-ray analyses provided justification for role of intermolecular interactions in aggregate morphology. Electrochemical and theoretical studies affirmed the effect of the A' strength on the overall properties of the A'-D-π-A system.

  10. Does anterior knee pain severity and function relate to the frontal plane projection angle and trunk and hip strength in women with patellofemoral pain?

    PubMed

    Almeida, Gabriel Peixoto Leão; Carvalho E Silva, Ana Paula de Moura Campos; França, Fábio Jorge Renovato; Magalhães, Maurício Oliveira; Burke, Thomaz Nogueira; Marques, Amélia Pasqual

    2015-07-01

    The aim of the present study was to determine the relationship between knee pain severity and function with the frontal plane projection angle (FPPA) and trunk and hip peak torque (PT) in women with patellofemoral pain (PFPS). Twenty-two women with PFPS were assessed. Knee pain severity (KPS) was assessed with an 11-point visual analog scale and function with an Anterior Knee Pain Scale. The FPPA was recorded with a digital camera. PT of extensors, abductors, and the lateral rotators of hip and lateral core stability were measured with a handheld dynamometer. FPPA was the only predictor for the KPS. Regarding predictors of function, PT of lateral core stability and the extensor and abductor of the hip explained 41.4% of the function. Increase in FPPA was associated with greater KPS, and the lowest PT of lateral core stability, hip abductors, and extensors was associated with lower function in women with PFPS.

  11. Does anterior knee pain severity and function relate to the frontal plane projection angle and trunk and hip strength in women with patellofemoral pain?

    PubMed

    Almeida, Gabriel Peixoto Leão; Carvalho E Silva, Ana Paula de Moura Campos; França, Fábio Jorge Renovato; Magalhães, Maurício Oliveira; Burke, Thomaz Nogueira; Marques, Amélia Pasqual

    2015-07-01

    The aim of the present study was to determine the relationship between knee pain severity and function with the frontal plane projection angle (FPPA) and trunk and hip peak torque (PT) in women with patellofemoral pain (PFPS). Twenty-two women with PFPS were assessed. Knee pain severity (KPS) was assessed with an 11-point visual analog scale and function with an Anterior Knee Pain Scale. The FPPA was recorded with a digital camera. PT of extensors, abductors, and the lateral rotators of hip and lateral core stability were measured with a handheld dynamometer. FPPA was the only predictor for the KPS. Regarding predictors of function, PT of lateral core stability and the extensor and abductor of the hip explained 41.4% of the function. Increase in FPPA was associated with greater KPS, and the lowest PT of lateral core stability, hip abductors, and extensors was associated with lower function in women with PFPS. PMID:26118529

  12. What Is a Strength?

    ERIC Educational Resources Information Center

    Wolin, Sybil

    2003-01-01

    As the strength-based perspective gains recognition, it is important to describe what constitutes strengths and to develop a specific vocabulary to name them. This article draws on resilience research to help identify specific competencies and areas of strengths in youth. (Contains 1 table.)

  13. Strength Training for Girls.

    ERIC Educational Resources Information Center

    Connaughton, Daniel; Connaughton, Angela; Poor, Linda

    2001-01-01

    Strength training can be fun, safe, and appropriate for young girls and women and is an important component of any fitness program when combined with appropriate cardiovascular and flexibility activities. Concerns and misconceptions regarding girls' strength training are discussed, presenting general principles of strength training for children…

  14. Growth kinetics of step edges on celestite (0 0 1) surfaces as a function of temperature, saturation state, ionic strength, and aqueous strontium:sulfate ratio: An in-situ atomic force microscopy study

    NASA Astrophysics Data System (ADS)

    Bracco, Jacquelyn N.; Gooijer, Yiscka; Higgins, Steven R.

    2016-02-01

    Step velocities on the celestite (0 0 1) surface have been measured as a function of temperature (23-45 °C), saturation state (S = 1.1-2.2), ionic strength (I = 0.01, 0.06, and 0.1 M), and aqueous strontium:sulfate ratio (r = 0.01-100) using atomic force microscopy (AFM). Celestite growth hillocks were flanked by [0 1 0]-aligned step edges, which are polar, and step edges vicinal to <1 2 0>, which are non-polar. [0 1 0] step velocities increased with temperature and saturation state, however step velocities did not vary significantly with ionic strength. Step velocities were non-linear with saturation state, suggesting a change in mechanism at high S as compared with low S. At constant S, the step velocities were maximized at r = 1 and decreased significantly at extreme r, demonstrating the governing role of solute stoichiometry. We successfully fit the step velocity data as a function of r using the Stack and Grantham (2010) nucleation and propagation model. Based on the results as a function of ionic strength and r, the mechanism at low S is likely ion-by-ion attachment to the step with an activation energy of 75 (±10) kJ mol-1. At high S the mechanism is a combination of the one at low S and possibly attachment of a neutral species such as an ion pair with an activation energy of 43 (±9) kJ mol-1.

  15. Growth kinetics of step edges on celestite (0 0 1) surfaces as a function of temperature, saturation state, ionic strength, and aqueous strontium:sulface ratio: An in-situ atomic force microscopy study

    SciTech Connect

    Bracco, Jacquelyn N.; Gooijer, Yiscka; Higgins, Steven R.

    2015-12-12

    Step velocities on the celestite (0 0 1) surface have been measured as a function of temperature (23–45 °C), saturation state (S = 1.1–2.2), ionic strength (I = 0.01, 0.06, and 0.1 M), and aqueous strontium:sulfate ratio (r = 0.01–100) using atomic force microscopy (AFM). Celestite growth hillocks were flanked by [0 1 0]-aligned step edges, which are polar, and step edges vicinal to <1 2 0>, which are non-polar. [0 1 0] step velocities increased with temperature and saturation state, however step velocities did not vary significantly with ionic strength. Step velocities were non-linear with saturation state, suggesting a change in mechanism at high S as compared with low S. At constant S, the step velocities were maximized at r = 1 and decreased significantly at extreme r, demonstrating the governing role of solute stoichiometry. We successfully fit the step velocity data as a function of r using the Stack and Grantham (2010) nucleation and propagation model. Based on the results as a function of ionic strength and r, the mechanism at low S is likely ion-by-ion attachment to the step with an activation energy of 75 (±10) kJ mol–1. In conclusion, at high S the mechanism is a combination of the one at low S and possibly attachment of a neutral species such as an ion pair with an activation energy of 43 (±9) kJ mol–1.

  16. Growth kinetics of step edges on celestite (0 0 1) surfaces as a function of temperature, saturation state, ionic strength, and aqueous strontium:sulface ratio: An in-situ atomic force microscopy study

    DOE PAGES

    Bracco, Jacquelyn N.; Gooijer, Yiscka; Higgins, Steven R.

    2015-12-12

    Step velocities on the celestite (0 0 1) surface have been measured as a function of temperature (23–45 °C), saturation state (S = 1.1–2.2), ionic strength (I = 0.01, 0.06, and 0.1 M), and aqueous strontium:sulfate ratio (r = 0.01–100) using atomic force microscopy (AFM). Celestite growth hillocks were flanked by [0 1 0]-aligned step edges, which are polar, and step edges vicinal to <1 2 0>, which are non-polar. [0 1 0] step velocities increased with temperature and saturation state, however step velocities did not vary significantly with ionic strength. Step velocities were non-linear with saturation state, suggesting amore » change in mechanism at high S as compared with low S. At constant S, the step velocities were maximized at r = 1 and decreased significantly at extreme r, demonstrating the governing role of solute stoichiometry. We successfully fit the step velocity data as a function of r using the Stack and Grantham (2010) nucleation and propagation model. Based on the results as a function of ionic strength and r, the mechanism at low S is likely ion-by-ion attachment to the step with an activation energy of 75 (±10) kJ mol–1. In conclusion, at high S the mechanism is a combination of the one at low S and possibly attachment of a neutral species such as an ion pair with an activation energy of 43 (±9) kJ mol–1.« less

  17. Formation of CaSO4(aq) and CaSeO4(aq) studied as a function of ionic strength and temperature by CE.

    PubMed

    Philippini, Violaine; Aupiais, Jean; Vercouter, Thomas; Moulin, Christophe

    2009-10-01

    Ca(2+) complexation by both sulfate and selenate ligands was studied by CE. The species were observed to give a unique retention peak as a result of a fast equilibrium between the free ions and the complexes. The change in the corresponding retention time was interpreted with respect to the equilibrium constant of the complexation reaction. The results confirmed the formation of CaSO(4)(aq) and CaSeO(4)(aq) under our experimental conditions. The formation data were derived from the series of measurements carried out at about 15, 25, 35, 45 and 55 degrees C in 0.1 mol/L NaNO(3) ionic strength solutions, and in 0.5 and 1.0 mol/L NaNO(3) ionic strength solutions at 25 degrees C. Using a constant enthalpy of reaction enabled to fit all the experimental data in a 0.1 mol/L medium, leading to the thermodynamic parameters: Delta(r)G(0.1M)(25 degrees C)=-(7.59+/-0.23) kJ/mol, Delta(r)H(0.1 M)=5.57+/-0.80 kJ/mol, and Delta(r)S(0.1 M)(25 degrees C)=44.0+/-3.0 J mol(-1) K(-1) for CaSO(4)(aq) and Delta(r)G(0.1 M)(25 degrees C)=-(6.66+/-0.23) kJ/mol, Delta(r)H(0.1 M)=6.45+/-0.73 kJ/mol, and Delta(r)S(0.1 M)(25 degrees C)=44.0+/-3.0 J mol(-1) K(-1) for CaSeO(4)(aq). Both formation reactions were found to be endothermic and entropy driven. CaSO(4)(aq) appears to be more stable than CaSeO(4)(aq) by 0.93 kJ/mol under these experimental conditions, which correlates with the difference of acidity of the anions as expected for interactions between hard acids and hard bases according to the hard and soft acids and bases theory. The effect of the ionic medium on the formation constants was successfully treated using the Specific ion Interaction Theory, leading to significantly different binary coefficients epsilon(NA+,SO(2-)(4)) = -(0.15 +/- 0.06) mol/kg-1 and epsilon(NA+,SO(2-)(4)) = -(0.26 +/- 0.10) mol/kg-1. PMID:19784954

  18. Strength Modeling Report

    NASA Technical Reports Server (NTRS)

    Badler, N. I.; Lee, P.; Wong, S.

    1985-01-01

    Strength modeling is a complex and multi-dimensional issue. There are numerous parameters to the problem of characterizing human strength, most notably: (1) position and orientation of body joints; (2) isometric versus dynamic strength; (3) effector force versus joint torque; (4) instantaneous versus steady force; (5) active force versus reactive force; (6) presence or absence of gravity; (7) body somatotype and composition; (8) body (segment) masses; (9) muscle group envolvement; (10) muscle size; (11) fatigue; and (12) practice (training) or familiarity. In surveying the available literature on strength measurement and modeling an attempt was made to examine as many of these parameters as possible. The conclusions reached at this point toward the feasibility of implementing computationally reasonable human strength models. The assessment of accuracy of any model against a specific individual, however, will probably not be possible on any realistic scale. Taken statistically, strength modeling may be an effective tool for general questions of task feasibility and strength requirements.

  19. Modeling the diffusion of Na+ in compacted water-saturated Na-bentonite as a function of pore water ionic strength

    SciTech Connect

    Bourg, I.C.; Sposito, G.; Bourg, A.C.M.

    2008-08-15

    Assessments of bentonite barrier performance in waste management scenarios require an accurate description of the diffusion of water and solutes through the barrier. A two-compartment macropore/nanopore model (on which smectite interlayer nanopores are treated as a distinct compartment of the overall pore space) was applied to describe the diffusion of {sup 22}Na{sup +} in compacted, water-saturated Na-bentonites and then compared with the well-known surface diffusion model. The two-compartment model successfully predicted the observed weak ionic strength dependence of the apparent diffusion coefficient (D{sub a}) of Na{sup +}, whereas the surface diffusion model did not, thus confirming previous research indicating the strong influence of interlayer nanopores on the properties of smectite clay barriers. Since bentonite mechanical properties and pore water chemistry have been described successfully with two-compartment models, the results in the present study represent an important contribution toward the construction of a comprehensive two-compartment model of compacted bentonite barriers.

  20. Strength Training, Not Only for the Young.

    ERIC Educational Resources Information Center

    Munnings, Frances

    1993-01-01

    Research indicates that increased strength leads to improved balance and functional mobility and that nearly every senior patient can benefit from basic resistance training. The article provides guidelines for physicians on prescribing resistance training and for patients on increasing strength. (SM)

  1. Water interaction and bond strength to dentin of dye-labelled adhesive as a function of the addition of rhodamine B

    PubMed Central

    WANG, Linda; BIM, Odair; LOPES, Adolfo Coelho de Oliveira; FRANCISCONI-DOS-RIOS, Luciana Fávaro; MAENOSONO, Rafael Massunari; D’ALPINO, Paulo Henrique Perlatti; HONÓRIO, Heitor Marques; ATTA, Maria Teresa

    2016-01-01

    ABSTRACT Objective This study investigated the effect of the fluorescent dye rhodamine B (RB) for interfacial micromorphology analysis of dental composite restorations on water sorption/solubility (WS/WSL) and microtensile bond strength to dentin (µTBS) of a 3-step total etch and a 2-step self-etch adhesive system. Material and Methods The adhesives Adper Scotchbond Multi-Purpose (MP) and Clearfil SE Bond (SE) were mixed with 0.1 mg/mL of RB. For the WS/WSL tests, cured resin disks (5.0 mm in diameter x 0.8 mm thick) were prepared and assigned into four groups (n=10): MP, MP-RB, SE, and SE-RB. For µTBS assessment, extracted human third molars (n=40) had the flat occlusal dentin prepared and assigned into the same experimental groups (n=10). After the bonding and restoration procedures, specimens were sectioned in rectangular beams, stored in water and tested after seven days or after 12 months. The failure mode of fractured specimens was qualitatively evaluated under optical microscope (x40). Data from WS/WSL and µTBS were assessed by one-way and three-way ANOVA, respectively, and Tukey’s test (α=5%). Results RB increased the WSL of MP and SE. On the other hand, WS of both MP and SE was not affected by the addition of RB. No significance in µTBS between MP and MP-RB for seven days or one year was observed, whereas for SE a decrease in the µTBS means occurred in both storage times. Conclusions RB should be incorporated into non-simplified DBSs with caution, as it can interfere with their physical-mechanical properties, leading to a possible misinterpretation of bonded interface. PMID:27556201

  2. Determining Electron-capture Rates of pf-shell Nuclei in Explosive Stellar Environments

    NASA Astrophysics Data System (ADS)

    Cole, A. L.; Dombos, A. C.; Zegers, R. G. T.; Austin, Sam M.; Brown, B. A.; Valdez, L.; Gupta, S.; Hitt, G. W.

    2011-10-01

    The electron-capture rates on pf-shell nuclei are required to model the evolution of core-collapse and thermonuclear supernovae. The majority of these rates are determined from calculated Gamow-Teller strength (B(GT)) distributions, as it's not feasible to measure the B(GT) distributions for all pf-shell nuclei. We present preliminary results of a systematic comparison between the electron-capture rates of 13 pf-shell nuclei determined from experimental B(GT) distribution measurements and the electron-capture rates of nuclei determined only from calculated B(GT) distributions, as measurements do not exist. The B(GT) distribution calculations were performed with the shell model using two different interaction Hamiltonians.

  3. Charge-exchange QRPA with the Gogny Force for Axially-symmetric Deformed Nuclei

    SciTech Connect

    Martini, M.; Goriely, S.; Péru, S.

    2014-06-15

    In recent years fully consistent quasiparticle random-phase approximation (QRPA) calculations using finite range Gogny force have been performed to study electromagnetic excitations of several axially-symmetric deformed nuclei up to the {sup 238}U. Here we present the extension of this approach to the charge-exchange nuclear excitations (pnQRPA). In particular we focus on the Isobaric Analog and Gamow-Teller resonances. A comparison of the predicted GT strength distribution with existing experimental data is presented. The role of nuclear deformation is shown. Special attention is paid to β-decay half-lives calculations for which experimental data exist and for specific isotone chains of relevance for the r-process nucleosynthesis.

  4. Shell-model analysis of the 136Xe double beta decay nuclear matrix elements.

    PubMed

    Horoi, M; Brown, B A

    2013-05-31

    Neutrinoless double beta decay, if observed, could distinguish whether the neutrino is a Dirac or a Majorana particle, and it could be used to determine the absolute scale of the neutrino masses. 136Xe is one of the most promising candidates for observing this rare event. However, until recently there were no positive results for the allowed and less rare two-neutrino double beta decay mode. The small nuclear matrix element associated with the long half-life represents a challenge for nuclear structure models used for its calculation. We report a new shell-model analysis of the two-neutrino double beta decay of 136Xe, which takes into account all relevant nuclear orbitals necessary to fully describe the associated Gamow-Teller strength. We further use the new model to analyze the main contributions to the neutrinoless double beta decay matrix element, and show that they are also diminished.

  5. Neutrino nuclear responses for double beta decays and astro neutrinos by charge exchange reactions

    NASA Astrophysics Data System (ADS)

    Ejiri, Hiroyasu

    2014-09-01

    Neutrino nuclear responses are crucial for neutrino studies in nuclei. Charge exchange reactions (CER) are shown to be used to study charged current neutrino nuclear responses associated with double beta decays(DBD)and astro neutrino interactions. CERs to be used are high energy-resolution (He3 ,t) reactions at RCNP, photonuclear reactions via IAR at NewSUBARU and muon capture reactions at MUSIC RCNP and MLF J-PARC. The Gamow Teller (GT) strengths studied by CERs reproduce the observed 2 neutrino DBD matrix elements. The GT and spin dipole (SD) matrix elements are found to be reduced much due to the nucleon spin isospin correlations and the non-nucleonic (delta isobar) nuclear medium effects. Impacts of the reductions on the DBD matrix elements and astro neutrino interactions are discussed.

  6. β-decay of magic nuclei: Beyond mean-field description

    SciTech Connect

    Niu, Yifei; Niu, Zhongming; Colò, Gianluca; Vigezzi, Enrico

    2015-10-15

    Nuclear β-decay plays an important role not only in nuclear physics but also in astrophysics. The widely used self-consistent Random Phase Approximation (RPA) models tend to overestimate the half-lives of magic nuclei. To overcome this problem, we go beyond the mean-field description and include the effects of particle-vibration coupling (PVC) on top of the RPA model. The β-decay half-lives of {sup 34}Si, {sup 68}Ni, {sup 78}Ni, and {sup 132}Sn are studied within this approach in the case of the Skyrme interaction SkM*. It is found that the low-lying Gamow-Teller (GT) strength is shifted downwards with the inclusion of the PVC effect, and as a consequence, the half-lives are reduced due to the increase of the phase space available for β-decay, which leads to a good agreement between theoretical and experimental lifetimes.

  7. Neutrino-induced reactions on {sup 56}Fe and {sup 56}Ni, and production of {sup 55}Mn in population III stars

    SciTech Connect

    Suzuki, Toshio; Honma, Michio; Higashiyama, Koji; Yoshida, Takashi; Umeda, Hideyuki; Kajino, Toshitaka; Otsuka, Takaharu; Nomoto, Ken'ichi

    2009-06-15

    Neutrino-induced reactions on {sup 56}Fe and {sup 56}Ni are investigated based on a new shell-model Hamiltonian for pf shell. The calculated charged current reaction cross section on {sup 56}Fe induced by decay-at-rest (DAR) neutrinos is shown to be consistent with the observation. The Gamow-Teller strength in {sup 56}Ni is found to be more spread compared to previous calculations and result in a considerably large branching ratio for the proton knock-out channel. As a consequence of this, the production yields of heavy elements such as {sup 55}Mn in population III stars are shown to be enhanced for the new Hamiltonian.

  8. Alumina fiber strength improvement

    NASA Technical Reports Server (NTRS)

    Pepper, R. T.; Nelson, D. C.

    1982-01-01

    The effective fiber strength of alumina fibers in an aluminum composite was increased to 173,000 psi. A high temperature heat treatment, combined with a glassy carbon surface coating, was used to prevent degradation and improve fiber tensile strength. Attempts to achieve chemical strengthening of the alumina fiber by chromium oxide and boron oxide coatings proved unsuccessful. A major problem encountered on the program was the low and inconsistent strength of the Dupont Fiber FP used for the investigation.

  9. The effects of a muscle resistance program on the functional capacity, knee extensor muscle strength and plasma levels of IL-6 and TNF-α in pre-frail elderly women: a randomized crossover clinical trial - a study protocol

    PubMed Central

    2010-01-01

    Background With the increase in the elderly population, a growing number of chronic degenerative diseases and a greater dependency on caregivers have been observed. Elderly persons in states of frailty remain more susceptible to significant health complications. There is evidence of an inverse relationship between plasma levels of inflammatory mediators and levels of functionality and muscle strength, suggesting that muscle-strengthening measures can aid in inflammatory conditions. The purpose of this study will be verified the effect of a muscle-strengthening program with load during a ten-week period in pre-frail elderly women with attention to the following outcomes: (1) plasma levels of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α), (2) functional capacity and (3) knee extensor muscle strength. Methods/Design The study design is a randomized crossover clinical trial evaluating 26 elderly women (regardless of their race and/or social condition) who are community residents, older than 65, and classified as pre-frail according to the criteria previously described by Fried et al. (2004). All subjects will be assessed using the Timed up and go and 10-Meter Walk Test functional tests. The plasma levels of IL-6 and TNF-α will be assessed by ELISA (enzyme-linked immunosorbent assay) with high sensitivity kits (Quantikine®HS, R&D Systems Minneapolis, MN, U.S.). Knee extensor muscle strength will be assessed using the Byodex System 3 Pro® isokinetic dynamometer at angular speeds of 60 and 180°/s. The intervention will consist of strengthening exercises of the lower extremities at 50 to 70% of 1RM (maximal resistance) three times per week for ten weeks. The volunteers will be randomized into two groups: group E, the intervention group, and group C, the control group that did not initiate any new activities during the initial study period (ten weeks). After the initial period, group C will begin the intervention and group E will maintain everyday

  10. Strength Training and Your Child

    MedlinePlus

    ... Story" 5 Things to Know About Zika & Pregnancy Strength Training and Your Child KidsHealth > For Parents > Strength Training ... help prevent injuries and speed up recovery. About Strength Training Strength training is the practice of using free ...

  11. Building on Our Strengths.

    ERIC Educational Resources Information Center

    Hill, Robert

    1978-01-01

    Comments on the feeling that the American family is disintegrating, and that many criticisms traditionally made about Black families are now made about White families. Suggests that people need to stress family strengths. As an example, five major strengths of Black families are described: flexibility, work and achievement ethics, religiosity, and…

  12. Strengths of Remarried Families.

    ERIC Educational Resources Information Center

    Knaub, Patricia Kain; And Others

    1984-01-01

    Focuses on remarried families' (N=80) perceptions of family strengths, marital satisfaction, and adjustment to the remarried situation. Results indicated that although most would like to make some changes, scores on the measurements used were high. A supportive environment was the most important predictor of family strength and success. (JAC)

  13. The flexible structure of the K24S28 region of Leucine-Rich Amelogenin Protein (LRAP) bound to apatites as a function of surface type, calcium, mutation, and ionic strength

    SciTech Connect

    Lu, Junxia; Burton, Sarah D.; Xu, Yimin; Buchko, Garry W.; Shaw, Wendy J.

    2014-07-11

    Leucine-Rich Amelogenin Protein (LRAP) is a member of the amelogenin family of biomineralization proteins, proteins which play a critical role in enamel formation. Recent studies have revealed the structure and orientation of the N- and C-terminus of LRAP bound to hydroxyapatite (HAP), a surface used as an analog of enamel. The structure of one region, K24 to S28, was found to be sensitive to phosphorylation of S16, the only naturally observed site of serine phosphorylation in LRAP, suggesting that the residues from K24 to S28 may sit at a key region of structural flexibility and play a role in the protein’s function. In this work, we investigated the sensitivity of the structure and orientation of this region when bound to HAP as a function of several factors which may vary during enamel formation to influence structure: the ionic strength (0.05 M, 0.15 M, 0.2 M), the calcium concentration (0.07 mM and 0.4 mM), and the surface to which it is binding (HAP and carbonated apatite (CAP), a more direct mimic of enamel). A naturally occurring mutation found in amelogenin (T21I), was also investigated. The structure in the K24S28 region of the protein was found to be sensitive to these conditions, with the CAP surface and excess Ca2+ (8:1 [Ca2+]:[LRAP-K24S28(+P)]) resulting in a much tighter helix, while low ionic strength relaxed the helical structure. Higher ionic strength and the point mutation did not result in any structural change in this region. The distance of the backbone of K24 from the surface was most sensitive to excess Ca2+ and in the T21I-mutation. Collectively, these data suggest that the protein is able to accommodate structural changes while maintaining its interaction with the surface, and provides further evidence of the structural sensitivity of the K24 to S28 region, a sensitivity that may contribute to function in biomineralization. This research was supported by NIH-NIDCR Grant DE-015347. The research was performed at the Pacific Northwest

  14. Improvements in skeletal muscle strength and cardiac function induced by resveratrol during exercise training contribute to enhanced exercise performance in rats.

    PubMed

    Dolinsky, Vernon W; Jones, Kelvin E; Sidhu, Robinder S; Haykowsky, Mark; Czubryt, Michael P; Gordon, Tessa; Dyck, Jason R B

    2012-06-01

    Exercise training (ET) improves endurance capacity by increasing both skeletal muscle mitochondrial number and function, as well as contributing to favourable cardiac remodelling.Interestingly, some of the benefits of regular exercise can also be mimicked by the naturally occurring polyphenol, resveratrol (RESV). However, it is not known whether RESV enhances physiological adaptations to ET. To investigate this, male Wistar rats were randomly assigned to a control chow diet or a chow diet that contained RESV (4 g kg⁻¹ of diet) and subsequently subjected to a programme of progressive treadmill running for 12 weeks. ET-induced improvements in exercise performance were enhanced by 21% (P <0.001) by the addition of RESV to the diet. In soleus muscle, ET+RESV increased both the twitch (1.8-fold; P <0.05) and tetanic(1.2-fold; P <0.05) forces generated during isometric contraction, compared to ET alone. In vivo echocardiography demonstrated that ET+RESV also increased the resting left ventricular ejection fraction by 10% (P <0.05), and reduced left ventricular wall stress compared to ET alone.These functional changes were accompanied by increased cardiac fatty acid oxidation (1.2-fold;P <0.05) and favourable changes in cardiac gene expression and signal transduction pathways that optimized the utilization of fatty acids in ET+RESV compared to ET alone. Overall, our findings provide evidence that the capacity for fatty acid oxidation is augmented by the addition of RESV to the diet during ET, and that this may contribute to the improved physical performance of rats following ET.

  15. The complete set of spin observables for the (13)C(polarized proton, polarized neutron)(13)N and (15)N(polarized proton, polarized neutron)(15)O reactions

    NASA Astrophysics Data System (ADS)

    Du, Qun Qun

    1998-12-01

    The 13C(p,n)13N and 15N(p,n)15O reactions have been a puzzle for more than ten years. The ground state transitions are Jπ=1/2- to Jπ=1/2-. These are 'mixed' transitions because they can involve quantum number changes either (/Delta T=1,/ /Delta J=0,/ /Delta/pi=0,/ /Delta S=0), or (/Delta T=1,/ /Delta J=1,/ /Delta/pi=0,/ /Delta S=1); these quantum number changes are refered to as 'Fermi' and 'Gamow-Teller' respectively. Because the quantum number changes are the same as for Fermi and Gamow-Teller beta decay. From the systematics of (p,n) and (n,p) reactions on pure Fermi transitions (e.g. 0 + to 0+) and pure Gamow-Teller transitions (e.g. 0+ to 1+), calibrations have been established of cross section per unit B(F) or unit B(GT), where 'B' refers to doubly reduced matrix elements extracted from beta decay. However, cross sections for the 13C(p,n)13N(g.s.) and 15N(p,n)15O(g.s.) reactions are substantially larger than one would then predict from the known B(F)s and B(GT)s for these transitions. To explore this anomaly, spin observables were used to extract separately the Fermi and Gamow-Teller cross sections for these reactions. To acquire the complete sets of polarization- transfer observables, a new neutron polarimeter was designed, built, commissioned and calibrated. This polarimeter, call the '2π polarimeter' because of its complete azimuthal coverage for scattered neutrons, has very good position and timing resolution (354 ps). The complete sets of spin-transfer coefficients Dij for 13C(p,n)13N (at 0o , 5.5o , and 11o ) and 15N(p,n)15O (at 0o ) at 135 MeV were measured. Following the formalism of Ichimura and Kawahigashi, we extracted the spin-longitudinal, and spin-transverse and spin-independent responses D0,/ Dq,/ Dn and Dp from the measured Dijs. The F and GT fractions of the (p,n) cross sections are then extracted as f F=D0 and fGT=Dn+Dp+Dq=1- d0. Values of Dk for both the 13C(p,n)13N(g.s) and 15N(p,n)15O(g.s.) were extracted. From these responses, we

  16. Relationship among fatigue strength, mean grain size and compressive strength of a rock

    NASA Astrophysics Data System (ADS)

    Singh, S. K.

    1988-10-01

    Fatigue tests carried on three sets of samples having different mean grain sizes revealed that fatigue strength is a function of mean grain size of the rock. Samples having smaller grain size show higher value of fatigue strength. Graywacke samples from Flagstaff formation having mean grain sizes of 1.79 mm, 1.35 mm and 0.93 mm showed fatigue strengths of 87%, 88.25% and 89.1% respectively. Since the mean uniaxial compressive strength also varied with varying grain size, i. e. higher mean strength value for samples having finer grain size; the fatigue strength of a rock also shows a converse relation with mean uniaxial compressive strength.

  17. The strength of sexual arousal as a function of the age of the sex offender: comparisons among pedophiles, hebephiles, and teleiophiles.

    PubMed

    Blanchard, Ray; Barbaree, Howard E

    2005-10-01

    Previous research has shown that sexual arousability in human males declines from its peak in early adolescence until old age. This study compared the rates of decline in three groups of males: those most attracted sexually to prepubescent children (pedophiles), those most attracted to pubescent children (hebephiles), and those most attracted to physically mature persons (teleiophiles). The participants were 2,028 patients referred to Toronto's Centre for Addiction and Mental Health from 1995 to 2004 for evaluation of criminal or otherwise disturbing sexual behavior, but not for erectile or ejaculatory problems. All underwent phallometric assessment for erotic age-preference. This is a psychophysiological technique in which an individual's penile blood volume is monitored while he is presented with a standardized set of laboratory stimuli depicting male and female children, pubescents, and adults. The experimental measure of sexual arousability was the average of the participant's three greatest penile responses to any stimulus category, expressed in cubic cm of blood volume increase. The results showed that sexual arousability was an inverse function of age, and that there were no differences between the pedophiles, hebephiles, and teleiophiles in the rate at which arousability declined. PMID:16341604

  18. Measurement of the resistance induced by a single atomic impurity on a (7,6) semiconducting carbon nanotube: scattering strength of individual potassium atoms as a function of gate voltage

    NASA Astrophysics Data System (ADS)

    Tsuchikawa, Ryuichi; Ahmadi, Amin; Heligman, Daniel; Zhang, Zhengyi; Mucciolo, Eduardo; Hone, James; Ishigami, Masa

    2015-03-01

    Despite many years of research, no measurements have been performed to determine resistance induced by impurities in carbon nanotubes. Over the last few years, we have developed a capability to measure the resistance induced by a single impurity atom on nanotubes with known chirality. Using this capability, we measured the resistance induced by an individual potassium atom on a (7,6) semiconducting carbon nanotube. The ``atomic'' resistance of potassium is found to be in the kohm range and has a strong dependence on the applied gate voltage. The scattering strength of the p-type (valence band) channel is approximately 20 times greater than that of the n-type (conduction band) channel. We integrate our atomically-controlled experimental result to a numerical recursive Green's function technique, which can precisely model the experiment, to understand the measured ``atomic'' resistance and the asymmetry. This work is based upon research supported by the National Science Foundation under Grant No. 0955625 and 1006230.

  19. Beta-Decay and Delayed Neutron Emission of Very Neutron-Rich Nuclei

    NASA Astrophysics Data System (ADS)

    Borzov, I. N.

    2014-09-01

    Extended self-consistent beta-decay model has been applied for beta-decay rates and delayed multi-neutron emission probabilities of quasi-spherical neutron-rich isotopes. The Gamow-Teller and first-forbidden decays are treated within the coordinate-space formalism of the continuum QRPA based on the density functional theory description of the ground state. A new set of the Fayans density functional parameters (DF3a) have been employed giving a better spin-orbit splitting due to a stronger tensor term. A provision has been included to fix the odd particle in the proper orbit (before variation). This accounts for ground-state spin inversion effect which has been shown to exist in the region of the most neutron-rich doubly-magic nucleus 78Ni.

  20. STRENGTH EXERCISES COMBINED WITH DRY NEEDLING WITH ELECTRICAL STIMULATION IMPROVE PAIN AND FUNCTION IN PATIENTS WITH CHRONIC ROTATOR CUFF TENDINOPATHY: A RETROSPECTIVE CASE SERIES

    PubMed Central

    2016-01-01

    ABSTRACT Background and Purpose Rotator cuff tendinopathy (RTCT) is regularly treated by the physical therapist. Multiple etiologies for RTCT exist, leading an individual to seek treatment from their provider of choice. Strengthening exercises (SE) have been reported to be effective in the treatment of RTCT, but there is limited evidence on the effectiveness of dry needing (DN) for this condition. The purpose of this retrospective case series was to investigate DN to various non-trigger point-based anatomical locations coupled with strengthening exercises (SE) as a treatment strategy to decrease pain and increase function in healthy patients with chronic RTC pathology. Case Descriptions Eight patients with RTCT were treated 1-2 times per week for up to eight weeks, and no more than sixteen total treatment sessions of SE and DN. Outcomes were tested at baseline and upon completion of therapy. A long-term outcome measure follow up averaging 8.75 months (range 3 to 20 months) was also performed. The outcome measures included the Visual Analog Scale (VAS) and the Quick Dash (QD). Outcomes Clinically meaningful improvements in disability and pain in the short term and upon long-term follow up were demonstrated for each patient. The mean VAS was broken down into best (VASB), current (VASC), and worst (VASW) rated pain levels and the mean was calculated for the eight patients. The mean VASB improved from 22.5 mm at the initial assessment to 2.36 mm upon completion of the intervention duration. The mean VASC improved from 28.36 mm to 5.0 mm, and the mean VASW improved from 68.88 mm to 13.25 mm. At the long-term follow up (average 8.75 months), The mean VASB, VASC, and VASW scores were 0.36 mm, 4.88 mm, and 17.88 mm respectively. The QDmean for the eight patients improved from 43.09 at baseline to 16.04 at the completion of treatment. At long-term follow-up, the QDmean was 6.59. Conclusion Clinically meaningful improvements in pain and disability were

  1. Crew Strength Training

    NASA Video Gallery

    Train to develop your upper and lower body strength in your muscles and bones by performing body-weight squats and push-ups.The Train Like an Astronaut project uses the excitement of exploration to...

  2. Developing Strengths in Families

    ERIC Educational Resources Information Center

    Bowman, Ted

    1976-01-01

    There are few descriptions of growth experiences for total families. This paper describes one such model. It expresses the conviction that families need opportunities to come together with other families to identify strengths, sharpen communication skills, and establish goals. (Author)

  3. Isospin-symmetry-breaking effects in A∼70 nuclei within beyond-mean-field approach

    SciTech Connect

    Petrovici, A.; Andrei, O.

    2015-02-24

    Particular isospin-symmetry-breaking probes including Coulomb energy differences (CED), mirror energy differences (MED), and triplet energy differences (TED) manifest anomalies in the A∼70 isovector triplets of nuclei. The structure of proton-rich nuclei in the A∼70 mass region suggests shape coexistence and competition between pairing correlations in different channels. Recent results concerning the interplay between isospin-mixing and shape-coexistence effects on exotic phenomena in A∼70 nuclei obtained within the beyond-mean-field complex Excited Vampir variational model with symmetry projection before variation using a realistic effective interaction in a relatively large model space are presented. Excited Vampir predictions concerning the Gamow-Teller β decay to the odd-odd N=Z {sup 66}As and {sup 70}Br nuclei correlated with the pair structure analysis in the T=1 and T=0 channel of the involved wave functions are discussed.

  4. Apple Strength Issues

    SciTech Connect

    Syn, C

    2009-12-22

    Strength of the apple parts has been noticed to decrease, especially those installed by the new induction heating system since the LEP campaign started. Fig. 1 shows the ultimate tensile strength (UTS), yield strength (YS), and elongation of the installed or installation-simulated apples on various systems. One can clearly see the mean values of UTS and YS of the post-LEP parts decreased by about 8 ksi and 6 ksi respectively from those of the pre-LEP parts. The slight increase in elongation seen in Fig.1 can be understood from the weak inverse relationship between the strength and elongation in metals. Fig.2 shows the weak correlation between the YS and elongation of the parts listed in Fig. 1. Strength data listed in Figure 1 were re-plotted as histograms in Figs. 3 and 4. Figs. 3a and 4a show histograms of all UTS and YS data. Figs. 3b and 4b shows histograms of pre-LEP data and Figs. 3c and 4c of post-LEP data. Data on statistical scatter of tensile strengths have been rarely published by material suppliers. Instead, only the minimum 'guaranteed' strength data are typically presented. An example of strength distribution of aluminum 7075-T6 sheet material, listed in Fig. 5, show that its scatter width of both UTS and YS for a single sheet can be about 6 ksi and for multi-lot scatter can be as large as 11 ksi even though the sheets have been produced through well-controlled manufacturing process. By approximating the histograms shown in Figs. 3 and 4 by a Gaussian or similar type of distribution curves, one can plausibly see the strength reductions in the later or more recent apples. The pre-LEP data in Figs. 3b and 4b show wider scatter than the post-LEP data in Figs. 3c and 4c and seem to follow the binomial distribution of strength indicating that the apples might have been made from two different lots of material, either from two different vendors or from two different melts of perhaps slightly different chemical composition by a single vendor. The post

  5. Probabilistic Modeling of Ceramic Matrix Composite Strength

    NASA Technical Reports Server (NTRS)

    Shan, Ashwin R.; Murthy, Pappu L. N.; Mital, Subodh K.; Bhatt, Ramakrishna T.

    1998-01-01

    Uncertainties associated with the primitive random variables such as manufacturing process (processing temperature, fiber volume ratio, void volume ratio), constituent properties (fiber, matrix and interface), and geometric parameters (ply thickness, interphase thickness) have been simulated to quantify the scatter in the first matrix cracking strength (FMCS) and the ultimate tensile strength of SCS-6/RBSN (SiC fiber (SCS-6) reinforced reaction-bonded silicon nitride composite) ceramic matrix composite laminate at room temperature. Cumulative probability distribution function for the FMCS and ultimate tensile strength at room temperature (RT) of (0)(sub 8), (0(sub 2)/90(sub 2), and (+/-45(sub 2))(sub S) laminates have been simulated and the sensitivity of primitive variables to the respective strengths have been quantified. Computationally predicted scatter of the strengths for a uniaxial laminate have been compared with those from limited experimental data. Also the experimental procedure used in the tests has been described briefly. Results show a very good agreement between the computational simulation and the experimental data. Dominating failure modes in (0)(sub 8), (0/90)(sub s) and (+/-45)(sub S) laminates have been identified. Results indicate that the first matrix cracking strength for the (0)(sub S), and (0/90)(sub S) laminates is sensitive to the thermal properties, modulus and strengths of both the fiber and matrix whereas the ultimate tensile strength is sensitive to the fiber strength and the fiber volume ratio. In the case of a (+/-45)(sub S), laminate, both the FMCS and the ultimate tensile strengths have a small scatter range and are sensitive to the fiber tensile strength as well as the fiber volume ratio.

  6. Effect of panel alignment and surface finish on bond strength

    SciTech Connect

    Wouters, J.M.; Doe, P.J.; Baker, W.E.

    1991-10-01

    The flexural strength of bonded acrylic is tested as a function of panel alignment and bond surface finish. Bond strength was shown to be highly dependent on both parameters with only a narrow range of values yielding a high strength bond. This study was performed for the heavy water-containing acrylic vessel for the Sudbury Neutrino Observatory detector.

  7. Effect of Die Strength and Work Piece Strength on the Wear of Hot Forging Dies

    NASA Astrophysics Data System (ADS)

    Levy, B. S.; Van Tyne, C. J.

    2015-01-01

    The effect of the strength ratio extracted from an Archard model for wear is used to describe the wear rates expected in hot forging dies. In the current study, the strength ratio is the strength of the hot forging die to the strength of the work piece. Three hot forging die steels are evaluated. The three die steels are FX, 2714, and WF. To determine the strength of the forging die, a continuous function has been developed that describes the yield strength of three die steels for temperatures from 600 to 700 °C and for times up to 20 h (i.e., tempering times of up to 20 h). The work piece material is assumed to be AISI 1045. Based on the analysis, the wear resistance of WF should be superior and FX should be slightly better than 2714. Decreasing the forging temperature increases the strength ratio, because the strength of the die surface increases faster than the flow strength of AISI 1045. The increase in the strength ratio indicates a decrease in the expected wear rate.

  8. High strength alloys

    DOEpatents

    Maziasz, Phillip James [Oak Ridge, TN; Shingledecker, John Paul [Knoxville, TN; Santella, Michael Leonard [Knoxville, TN; Schneibel, Joachim Hugo [Knoxville, TN; Sikka, Vinod Kumar [Oak Ridge, TN; Vinegar, Harold J [Bellaire, TX; John, Randy Carl [Houston, TX; Kim, Dong Sub [Sugar Land, TX

    2010-08-31

    High strength metal alloys are described herein. At least one composition of a metal alloy includes chromium, nickel, copper, manganese, silicon, niobium, tungsten and iron. System, methods, and heaters that include the high strength metal alloys are described herein. At least one heater system may include a canister at least partially made from material containing at least one of the metal alloys. At least one system for heating a subterranean formation may include a tubular that is at least partially made from a material containing at least one of the metal alloys.

  9. High strength alloys

    DOEpatents

    Maziasz, Phillip James; Shingledecker, John Paul; Santella, Michael Leonard; Schneibel, Joachim Hugo; Sikka, Vinod Kumar; Vinegar, Harold J.; John, Randy Carl; Kim, Dong Sub

    2012-06-05

    High strength metal alloys are described herein. At least one composition of a metal alloy includes chromium, nickel, copper, manganese, silicon, niobium, tungsten and iron. System, methods, and heaters that include the high strength metal alloys are described herein. At least one heater system may include a canister at least partially made from material containing at least one of the metal alloys. At least one system for heating a subterranean formation may include a tublar that is at least partially made from a material containing at least one of the metal alloys.

  10. Spin resonance strength calculations

    SciTech Connect

    Courant,E.D.

    2008-10-06

    In calculating the strengths of depolarizing resonances it may be convenient to reformulate the equations of spin motion in a coordinate system based on the actual trajectory of the particle, as introduced by Kondratenko, rather than the conventional one based on a reference orbit. It is shown that resonance strengths calculated by the conventional and the revised formalisms are identical. Resonances induced by radiofrequency dipoles or solenoids are also treated; with rf dipoles it is essential to consider not only the direct effect of the dipole but also the contribution from oscillations induced by it.

  11. Notch strength of composites

    NASA Technical Reports Server (NTRS)

    Whitney, J. M.

    1983-01-01

    The notch strength of composites is discussed. The point stress and average stress criteria relate the notched strength of a laminate to the average strength of a relatively long tensile coupon. Tests of notched specimens in which microstrain gages have been placed at or near the edges of the holes have measured strains much larger that those measured in an unnotched tensile coupon. Orthotropic stress concentration analyses of failed notched laminates have also indicated that failure occurred at strains much larger than those experienced on tensile coupons with normal gage lengths. This suggests that the high strains at the edge of a hole can be related to the very short length of fiber subjected to these strains. Lockheed has attempted to correlate a series of tests of several laminates with holes ranging from 0.19 to 0.50 in. Although the average stress criterion correlated well with test results for hole sizes equal to or greater than 0.50 in., it over-estimated the laminate strength in the range of hole sizes from 0.19 to 0.38 in. It thus appears that a theory is needed that is based on the mechanics of failure and is more generally applicable to the range of hole sizes and the varieties of laminates found in aircraft construction.

  12. High strength composites evaluation

    SciTech Connect

    Marten, S.M.

    1992-02-01

    A high-strength, thick-section, graphite/epoxy composite was identified. The purpose of this development effort was to evaluate candidate materials and provide LANL with engineering properties. Eight candidate materials (Samples 1000, 1100, 1200, 1300, 1400, 1500, 1600, and 1700) were chosen for evaluation. The Sample 1700 thermoplastic material was the strongest overall.

  13. Density functional theory simulation of hydrogen-bonding structure and vibrational densities of states at the quartz (101)-water interface and its relation to dissolution as a function of solution pH and ionic strength.

    PubMed

    DelloStritto, M J; Kubicki, J; Sofo, J O

    2014-06-18

    Two hypotheses for the dissolution of SiO2 in ionic solutions are investigated via ab initio molecular dynamics (AIMD) simulations. The hypotheses are (1) that the presence of ions induces orientations in H2O molecules at the surface, which favor proton transfer to bridging oxygen (BO) atoms, and (2) the presence of ions induces stronger H-bonding between terminal hydroxyl (TH) groups and BO atoms, allowing proton transfer. It is found that the model structures produced by density functional theory simulations do not support the former hypothesis and are more consistent with the latter.

  14. Solution ionic strength engineering as a generic strategy to coat graphene oxide (GO) on various functional particles and its application in high-performance lithium-sulfur (Li-S) batteries.

    PubMed

    Rong, Jiepeng; Ge, Mingyuan; Fang, Xin; Zhou, Chongwu

    2014-02-12

    A generic and facile method of coating graphene oxide (GO) on particles is reported, with sulfur/GO core-shell particles demonstrated as an example for lithium-sulfur (Li-S) battery application with superior performance. Particles of different diameters (ranging from 100 nm to 10 μm), geometries, and compositions (sulfur, silicon, and carbon) are successfully wrapped up by GO, by engineering the ionic strength in solutions. Importantly, our method does not involve any chemical reaction between GO and the wrapped particles, and therefore, it can be extended to vast kinds of functional particles. The applications of sulfur/GO core-shell particles as Li-S battery cathode materials are further investigated, and the results show that sulfur/GO exhibit significant improvements over bare sulfur particles without coating. Galvanic charge-discharge test using GO/sulfur particles shows a specific capacity of 800 mAh/g is retained after 1000 cycles at 1 A/g current rate if only the mass of sulfur is taken into calculation, and 400 mAh/g if the total mass of sulfur/GO is considered. Most importantly, the capacity decay over 1000 cycles is less than 0.02% per cycle. The coating method developed in this study is facile, robust, and versatile and is expected to have wide range of applications in improving the properties of particle materials.

  15. Handgrip strength, quadriceps muscle power, and optimal shortening velocity roles in maintaining functional abilities in older adults living in a long-term care home: a 1-year follow-up study

    PubMed Central

    Kozicka, Izabela; Kostka, Tomasz

    2016-01-01

    Purpose To assess the relative role of handgrip strength (HGS), quadriceps muscle power (Pmax), and optimal shortening velocity (υopt) in maintaining functional abilities (FAs) in older adults living in a long-term care home over a 1-year follow-up. Subjects and methods Forty-one inactive older institutionalized adults aged 69.8±9.0 years participated in this study. HGS, Pmax, υopt, cognitive function using the Mini-Mental State Examination, depressive symptoms using the Geriatric Depression Scale, nutritional status using the Mini Nutritional Assessment (MNA), and physical activity (PA) using the Seven-Day Physical Activity Recall Questionnaire were assessed at baseline and at 1-year follow-up. FAs were assessed with activities of daily living (ADL), instrumental ADL, and Timed Up & Go test. Results Both at baseline and at follow-up, FAs were related to age, HGS, Pmax/kg, υopt, MNA, and PA. These associations were generally similar in both sexes. As revealed in multiple regression analysis, υopt was the strongest predictor of FA, followed by Pmax/kg, PA, and MNA. FA deteriorated after 1 year as measured by ADL and Timed Up & Go test. Pmax and υopt, but not HGS, also decreased significantly after 1 year. Nevertheless, 1-year changes in FAs were not related to changes in HGS, Pmax, υopt, or PA. Conclusion The 1-year period of physical inactivity among older institutionalized adults was found to have a negative effect on their FAs, Pmax, and υopt. The present study demonstrates that Pmax and, especially, υopt correlated with FAs of older adults more than HGS, both at baseline and at follow-up. Despite this, 1-year natural fluctuations of PA, Pmax, and υopt are not significant enough to influence FAs in inactive institutionalized older adults. PMID:27307720

  16. Relation between hand grip strength, respiratory muscle strength and spirometric measures in male nursing home residents.

    PubMed

    Bahat, Gulistan; Tufan, Asli; Ozkaya, Hilal; Tufan, Fatih; Akpinar, Timur Selçuk; Akin, Sibel; Bahat, Zumrut; Kaya, Zuleyha; Kiyan, Esen; Erten, Nilgün; Karan, Mehmet Akif

    2014-09-01

    Adverse-outcomes related to sarcopenia are mostly mentioned as physical disability. As the other skeletal muscles, respiratory muscles may also be affected by sarcopenia. Respiratory muscle strength is known to affect pulmonary functions. Therefore, we aimed to investigate the relations between extremity muscle strength, respiratory muscle strengths and spirometric measures in a group of male nursing home residents. Among a total of 104 male residents, residents with obstructive measures were excluded and final study population was composed of 62 residents. Mean age was 70.5 ± 6.7 years, body mass index: 27.7 ± 5.3 kg/m2 and dominant hand grip strength: 29.7 ± 6.5 kg. Hand grip strength was positively correlated with maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) (r = 0.35, p < 0.01 and r = 0.26, p < 0.05, respectively). In regression analysis, the only factor related to MIP was hand grip strength; among spirometric measures only parameter significantly related to grip strength was peak cough flow (PCF). The association of PCF with grip strength disappeared when MIP alone or "MIP and MEP" were included in the regression analysis. In the latter case, PCF was significantly associated only with MIP. We found peripheric muscle strength be associated with MIP and PCF but not with MEP or any other spirometric parameters. The relation between peripheral muscle strength and PCF was mediated by MIP. Our findings suggest that sarcopenia may affect inspiratory muscle strength earlier or more than the expiratory muscle strength. Sarcopenia may cause decrease in PCF in the elderly, which may stand for some common adverse respiratory complications.

  17. Nutritional Supplements for Strength Power Athletes

    NASA Astrophysics Data System (ADS)

    Wilborn, Colin

    Over the last decade research involving nutritional supplementation and sport performance has increased substantially. Strength and power athletes have specific needs to optimize their performance. Nutritional supplementation cannot be viewed as a replacement for a balanced diet but as an important addition to it. However, diet and supplementation are not mutually exclusive, nor does one depend on the other. Strength and power athletes have four general areas of supplementation needs. First, strength athletes need supplements that have a direct effect on performance. The second group of supplements includes those that promote recovery. The third group comprises the supplements that enhance immune function. The last group of supplements includes those that provide energy or have a direct effect on the workout. This chapter reviews the key supplements needed to optimize the performance and training of the strength athlete.

  18. Corium crust strength measurements.

    SciTech Connect

    Lomperski, S.; Nuclear Engineering Division

    2009-11-01

    Corium strength is of interest in the context of a severe reactor accident in which molten core material melts through the reactor vessel and collects on the containment basemat. Some accident management strategies involve pouring water over the melt to solidify it and halt corium/concrete interactions. The effectiveness of this method could be influenced by the strength of the corium crust at the interface between the melt and coolant. A strong, coherent crust anchored to the containment walls could allow the yet-molten corium to fall away from the crust as it erodes the basemat, thereby thermally decoupling the melt from the coolant and sharply reducing the cooling rate. This paper presents a diverse collection of measurements of the mechanical strength of corium. The data is based on load tests of corium samples in three different contexts: (1) small blocks cut from the debris of the large-scale MACE experiments, (2) 30 cm-diameter, 75 kg ingots produced by SSWICS quench tests, and (3) high temperature crusts loaded during large-scale corium/concrete interaction (CCI) tests. In every case the corium consisted of varying proportions of UO{sub 2}, ZrO{sub 2}, and the constituents of concrete to represent a LWR melt at different stages of a molten core/concrete interaction. The collection of data was used to assess the strength and stability of an anchored, plant-scale crust. The results indicate that such a crust is likely to be too weak to support itself above the melt. It is therefore improbable that an anchored crust configuration could persist and the melt become thermally decoupled from the water layer to restrict cooling and prolong an attack of the reactor cavity concrete.

  19. Strength calculations on airplanes

    NASA Technical Reports Server (NTRS)

    Baumann, A

    1925-01-01

    Every strength calculation, including those on airplanes, must be preceded by a determination of the forces to be taken into account. In the following discussion, it will be assumed that the magnitudes of these forces are known and that it is only a question of how, on the basis of these known forces, to meet the prescribed conditions on the one hand and the practical requirements on the other.

  20. Strength of nonuniformly oxidized PGX graphite

    SciTech Connect

    Price, R.J.; Beavan, L.A.

    1981-05-01

    Flexural and tensile tests were performed on PGX graphite oxidized to produce a steep surface oxidation gradient. Companion tensile specimens were oxidized under different conditions to produce uniform oxidation throughout the specimen, and their tensile strength and Young's modulus were measured. The flexural strength, flexural elastic modulus, and tensile strength were reduced much less by surface oxidation than by uniform oxidation. The test data were in good agreement with a simple linear elastic model in which Young's modulus at any point is a function of oxidation burnoff, and the strain at failure is independent of oxidation. The unoxidized interior of the specimens appears unaffected by the surface burnoff and remains able to fulfill its load-bearing function. 18 figures, 8 tables.

  1. [Measuring the handgrip strength of geriatric patients].

    PubMed

    Kerckhofs, A G M; Vandewoude, M F J; Mudde, A N

    2014-09-01

    The handgrip strength of geriatric patients can be measured when the patient is hospitalized. This article elaborates on the intrinsic and extrinsic factors which have a direct or indirect influence on handgrip strength. For the best results the tests need to be taken in the best circumstances with attention to individual differences and the age of the patient. Handgrip strength as determination of biological vitality is a key concept. Besides the physical characteristics there are many psychological factors (cognition, psyching-up, test attitude…) influencing the results. These are barely mentioned or not mentioned at all in the usual procedures. Research of handgrip strength testing theories is mostly focused on young, healthy adults and less on elderly patients. The main goal of this article is stimulating experimental research on the measurement of handgrip strength with elderly people and involving them more actively with the procedure. It is not enough to acquire insight in function and predicting characteristics of handgrip strength. Next to the aiming for the best test performance is 'working interactively with elderly patients' a goal on itself in the modern vision of health care.

  2. Simulation studies for surfaces and materials strength

    NASA Technical Reports Server (NTRS)

    Halicioglu, Timur

    1988-01-01

    During this six month period of the Simulation Studies for Surfaces and Materials Strength program investigations were carried out in two general areas: (1) Energy barriers and structural transitions between isomers of small Al clusters were investigated. In this study an empirical potential function which was parametrized based on accurate first principle results was employed; (2) A comparative study was conducted to investigate the applicability of most commonly employed model potential functions in calculating various bulk, surface and small cluster properties.

  3. Dynamic Strength of Materials

    NASA Astrophysics Data System (ADS)

    Chhabildas, Lalit

    2011-06-01

    Historically when shock loading techniques became accessible in the early fifties it was assumed that materials behave like fluids implying that materials cannot support any shear stresses. Early and careful investigation in the sixties by G. R. Fowles in aluminum indicated otherwise. When he compared his Hugoniot compression measurements to hydrostatic pressure compression measurements in the pressure volume plane he noticed that the shock data lay above the hydrostatic compression curve - which laid the ground work for what is the basis for elastic-plastic theories that exist today. In this talk, a brief historical perspective on strength measurements in materials will be discussed including how time-resolved techniques have played a role in allowing estimates of the strength of materials at over Mbar stress. This is crucial especially at high stresses since we are determining values that are small compared to the loading stress. Even though we have made considerable progress in our understanding of materials, there are still many anomalies and unanswered questions. Some of these anomalies are fertile grounds for further and future research and will be mentioned.

  4. Strength Training and Children's Health.

    ERIC Educational Resources Information Center

    Faigenbaum, Avery D.

    2001-01-01

    Provides an overview of the potential health benefits of strength training for children, discussing the role of strength training in preventing sports-related injuries and highlighting design considerations for such programs. The focus is on musculoskeletal adaptations to strength training that are observable in healthy children. Guidelines for…

  5. Strength Development for Young Adolescents

    ERIC Educational Resources Information Center

    McDaniel, Larry W.; Jackson, Allen; Gaudet, Laura

    2009-01-01

    Participation in strength training is important for older children or young adolescences who wish to improve fitness or participate in sports. When designing strength training programs for our youth this age group is immature anatomically, physiologically, and psychologically. For the younger or inexperienced group the strength training activities…

  6. Comparison of quadriceps strength and handgrip strength in their association with health outcomes in older adults in primary care.

    PubMed

    Chan, On Ying A; van Houwelingen, Anne H; Gussekloo, Jacobijn; Blom, Jeanet W; den Elzen, Wendy P J

    2014-01-01

    Sarcopenia is thought to play a major role in the functional impairment that occurs with old age. In clinical practice, sarcopenia is often determined by measuring handgrip strength. Here, we compared the lower limb quadriceps strength to the handgrip strength in their association with health outcomes in older adults in primary care. Our study population consisted of older adults (n = 764, 68.2% women, median age 83) that participated in the Integrated Systemic Care for Older People (ISCOPE) study. Participants were visited at baseline to measure quadriceps strength and handgrip strength. Data on health outcomes were obtained at baseline and after 12 months (including life satisfaction, disability in daily living, GP contact-time and hospitalization). Quadriceps strength and handgrip strength showed a weak association (β = 0.42 [95% CI 0.33-0.50]; R (2) = 0.17). Quadriceps strength and handgrip strength were independently associated with health outcomes at baseline, including quality of life, disability in daily living, GP contact-time, hospitalization, and gait speed. Combined weakness of the quadriceps and handgrip distinguished a most vulnerable subpopulation that presented with the poorest health outcomes. At follow-up, handgrip strength showed an association with quality of life (β = 0.05; P = 0.002) and disability in daily living (β = -0.5; P = 0.004). Quadriceps weakness did not further contribute to the prediction of the measured health outcomes. We conclude that quadriceps strength is only moderately associated with handgrip strength in an older population and that the combination of quadriceps strength and handgrip strength measurements may aid in the identification of older adults in primary care with the poorest health outcomes. In the prediction of poor health outcomes, quadriceps strength measurements do not show an added value to the handgrip strength.

  7. Gaseous hydrogen embrittlement of high strength steels

    NASA Technical Reports Server (NTRS)

    Gangloff, R. P.; Wei, R. P.

    1977-01-01

    The effects of temperature, hydrogen pressure, stress intensity, and yield strength on the kinetics of gaseous hydrogen assisted crack propagation in 18Ni maraging steels were investigated experimentally. It was found that crack growth rate as a function of stress intensity was characterized by an apparent threshold for crack growth, a stage where the growth rate increased sharply, and a stage where the growth rate was unchanged over a significant range of stress intensity. Cracking proceeded on load application with little or no detectable incubation period. Gaseous hydrogen embrittlement susceptibility increased with increasing yield strength.

  8. Failure strength of icy lithospheres

    NASA Technical Reports Server (NTRS)

    Golombek, M. P.; Banerdt, W. B.

    1987-01-01

    Lithospheric strengths derived from friction on pre-existing fractures and ductile flow laws show that the tensile strength of intact ice under applicable conditions is actually an order of magnitude stronger than widely assumed. It is demonstrated that this strength is everywhere greater than that required to initiate frictional sliding on pre-existing fractures and faults. Because the tensile strength of intact ice increases markedly with confining pressure, it actually exceeds the frictional strength at all depths. Thus, icy lithospheres will fail by frictional slip along pre-existing fractures at yeild stresses greater than previously assumed rather than opening tensile cracks in intact ice.

  9. QM02 Strength Measurement

    SciTech Connect

    Welch, J; Wu, J.; /SLAC

    2010-11-24

    In late April, Paul Emma reported that his orbit fitting program could find a reasonably good fit only if the strength of QM02 was changed from design value of -5.83 kG to -6.25 kG - a strength change of 7.3%. In late May, we made a focal length measurement of QM02 by turning off all focusing optics between YC07 and BPMS1 (in the spectrometer line) except for QM02 and adjusted the strength of QM02 so that vertical kicks by YC07 did not produce any displacements at BPMS1 (see Figure 1). The result was quoted in the LCLS elog was that QM02 appeared to 6% too weak, and approximately agreed with Paul's observation. The analysis used for the entry in the log book was based on the thin lens approximation and used the following numbers: Distance YC07 to QM02 - 5.128 m; Distance QM02 to BPMS1 - 1.778 m; and Energy - 135 MeV. These distances were computed from the X,Z coordinates given the on the large plot of the Injector on the wall of the control room. On review of the MAD output file coordinates, it seems that the distance used for QM02 to BPMS1 is not 1.778 m. The correct value is Distance, center of QM02 to BPMS1 - 1.845 m. There may be a typo on the wall chart values for the coordinates of BPMS1, or perhaps there was a misinterpretation of edge versus center of QM02. In any case, the effect of this change is that the thin lens estimate changes from 6% too weak to 9% too weak. At John Galayda's suggestion, we looked into the thin lens versus thick lens approximation. A Mathematica program was written to solve for the K value of the QM02, in the thick lens approximation, that provides point to point focusing from YC07 to BPMS1, and to compare this number with the value obtained using the thin lens approximation. The length of QM02 used in the thick lens calculation is the effective length determined by magnetic measurements of 0.108 m. The result of the Mathematica calculation is that the thin lens approximation predicts less magnet strength is required to produce the

  10. Gaussian discriminating strength

    NASA Astrophysics Data System (ADS)

    Rigovacca, L.; Farace, A.; De Pasquale, A.; Giovannetti, V.

    2015-10-01

    We present a quantifier of nonclassical correlations for bipartite, multimode Gaussian states. It is derived from the Discriminating Strength measure, introduced for finite dimensional systems in Farace et al., [New J. Phys. 16, 073010 (2014), 10.1088/1367-2630/16/7/073010]. As the latter the new measure exploits the quantum Chernoff bound to gauge the susceptibility of the composite system with respect to local perturbations induced by unitary gates extracted from a suitable set of allowed transformations (the latter being identified by posing some general requirements). Closed expressions are provided for the case of two-mode Gaussian states obtained by squeezing or by linearly mixing via a beam splitter a factorized two-mode thermal state. For these density matrices, we study how nonclassical correlations are related with the entanglement present in the system and with its total photon number.

  11. High strength ferritic alloy

    DOEpatents

    Hagel, William C.; Smidt, Frederick A.; Korenko, Michael K.

    1977-01-01

    A high-strength ferritic alloy useful for fast reactor duct and cladding applications where an iron base contains from about 9% to about 13% by weight chromium, from about 4% to about 8% by weight molybdenum, from about 0.2% to about 0.8% by weight niobium, from about 0.1% to about 0.3% by weight vanadium, from about 0.2% to about 0.8% by weight silicon, from about 0.2% to about 0.8% by weight manganese, a maximum of about 0.05% by weight nitrogen, a maximum of about 0.02% by weight sulfur, a maximum of about 0.02% by weight phosphorous, and from about 0.04% to about 0.12% by weight carbon.

  12. Where Is the Electronic Oscillator Strength? Mapping Oscillator Strength across Molecular Absorption Spectra.

    PubMed

    Zheng, Lianjun; Polizzi, Nicholas F; Dave, Adarsh R; Migliore, Agostino; Beratan, David N

    2016-03-24

    The effectiveness of solar energy capture and conversion materials derives from their ability to absorb light and to transform the excitation energy into energy stored in free carriers or chemical bonds. The Thomas-Reiche-Kuhn (TRK) sum rule mandates that the integrated (electronic) oscillator strength of an absorber equals the total number of electrons in the structure. Typical molecular chromophores place only about 1% of their oscillator strength in the UV-vis window, so individual chromophores operate at about 1% of their theoretical limit. We explore the distribution of oscillator strength as a function of excitation energy to understand this circumstance. To this aim, we use familiar independent-electron model Hamiltonians as well as first-principles electronic structure methods. While model Hamiltonians capture the qualitative electronic spectra associated with π electron chromophores, these Hamiltonians mistakenly focus the oscillator strength in the fewest low-energy transitions. Advanced electronic structure methods, in contrast, spread the oscillator strength over a very wide excitation energy range, including transitions to Rydberg and continuum states, consistent with experiment. Our analysis rationalizes the low oscillator strength in the UV-vis spectral region in molecules, a step toward the goal of oscillator strength manipulation and focusing.

  13. Strength Training: A Natural Prescription for Staying Healthy and Fit.

    ERIC Educational Resources Information Center

    Adams, Raymond, Ed.

    2003-01-01

    This newsletter highlights the importance of strength training in keeping older adults healthy and fit, explaining how it can forestall declines in strength and muscle mass, along with their attendant negative impact upon other metabolic functions and activities of daily living. Physical inactivity is common throughout the nation. Approximately 11…

  14. Celebrate Strengths, Nurture Affinities: A Conversation with Mel Levine

    ERIC Educational Resources Information Center

    Scherer, Marge

    2006-01-01

    In this interview with "Educational Leadership," pediatrician Dr. Mel Levine, cofounder of "All Kinds of Minds," explains why students and educators should learn about eight neurodevelopmental functions that undergird our strengths and weaknesses. For the most part, he notes, adults who lead successful lives mobilize their strengths and compensate…

  15. Strength of Chemical Bonds

    NASA Technical Reports Server (NTRS)

    Christian, Jerry D.

    1973-01-01

    Students are not generally made aware of the extraordinary magnitude of the strengths of chemical bonds in terms of the forces required to pull them apart. Molecular bonds are usually considered in terms of the energies required to break them, and we are not astonished at the values encountered. For example, the Cl2 bond energy, 57.00 kcal/mole, amounts to only 9.46 x 10(sup -20) cal/molecule, a very small amount of energy, indeed, and impossible to measure directly. However, the forces involved in realizing the energy when breaking the bond operate over a very small distance, only 2.94 A, and, thus, f(sub ave) approx. equals De/(r - r(sub e)) must be very large. The forces involved in dissociating the molecule are discussed in the following. In consideration of average forces, the molecule shall be assumed arbitrarily to be dissociated when the atoms are far enough separated so that the potential, relative to that of the infinitely separated atoms, is reduced by 99.5% from the potential of the molecule at the equilibrium bond length (r(sub e)) for Cl2 of 1.988 A this occurs at 4.928 A.

  16. Tensile strength of restorative resins.

    PubMed

    Zidan, O; Asmussen, E; Jørgensen, K D

    1980-06-01

    The purpose of the present work was to measure the tensile strength of restorative resins and to study the effect of the method of measurement on the recorded results. A direct pull method using dumb-bell shaped specimens was used. The tensile strength of the resins was also tested using the diametral compression method suggested by the A.D.A. It was found that the method of testing affects the results. Although the diametral compression method is a simple method, it cannot be considered reliable for all types of material. The tensile strength of the conventional composites was significantly higher than the tensile strength of the microfilled composites.

  17. Physiological Effects of Strength Training and Various Strength Training Devices.

    ERIC Educational Resources Information Center

    Wilmore, Jack H.

    Current knowledge in the area of muscle physiology is a basis for a discussion on strength training programs. It is now recognized that the expression of strength is related to, but not dependent upon, the size of the muscle and is probably more related to the ability to recruit more muscle fibers in the contraction, or to better synchronize their…

  18. Modeling the Evolution of Strength During Wire Drawing

    SciTech Connect

    Lesuer, D R; Syn, C K; Sherby, O D

    2002-08-05

    Extensive plastic deformation during wire drawing is commonly used to produce steel wires with very high strengths. Typically these steels are eutectoid and hypereutectoid steels and drawing strains up to 4 are used during processing. The resulting materials can have tensile strengths in excess of 4000 MPa. The evolution of microstructure and the strengthening mechanisms resulting from wire drawing have been studied for eutectoid and hypereutectoid steels. Strength has been shown to be a function of pearlite colony size, interlamellar spacing and the size of the stable dislocation cells that are produced during wire drawing. The results have been used to model the evolution of strength during wire drawing. Model predictions for the evolution of tensile strength with drawing strain show excellent agreement with data derived from a number of eutectoid and hyperectectoid steels as a function of drawing strain.

  19. Sex Differences in Tibial Bone Strength

    NASA Technical Reports Server (NTRS)

    Arnaud, Sara B.; Hutchinson, T. M.; Torikoshi, S.; Hutchinson, K. J.; Hargens, Alan R.; Steele, C. R.

    1995-01-01

    We have used an instrument (MRTA or Mechanical Response Tissue Analyzer) that measures bending stiffness (EI) non-Invasively to evaluate the strength of the tibia, a long bone in the weightbearing skeleton highly vulnerable to mineral loss during space flight. In healthy men, we found asymmetry in EI consistent with the bone's support function (L greater than R). In this study, we analyzed EI in women and compared the results to those in men.

  20. Bearing strength of the lunar soil

    NASA Technical Reports Server (NTRS)

    Jaffe, L. D.

    1972-01-01

    A discussion is presented on the bearing strength and bearing load-penetration relations in lunar soil. These were measured in air as a function of bulk density. It was found that the relation between bulk density and the logarithm of the bearing capacity is about linear. Shapes of the load vs penetration curves were observed to be similar to those obtained with particulate material of terrestrial origin.

  1. The effects of strength training on finger strength and hand dexterity in healthy elderly individuals

    PubMed Central

    Olafsdottir, Halla B.; Zatsiorsky, Vladimir M.; Latash, Mark L.

    2008-01-01

    We investigated the effect of 6 wk of strength training on maximal pressing (MVC) force, indexes of finger individuation (enslaving), and performance in accurate force production tests and in functional hand tests in healthy, physically fit, elderly individuals. Twelve participants (average age 76 yr) exercised with both hands. One of the hands exercised by pressing with the proximal phalanges (targeting mainly intrinsic hand muscles), whereas the other hand exercised by pressing with the finger tips (targeting mainly extrinsic hand muscles). Training led to higher MVC forces, higher enslaving indexes, and improved performance on the pegboard grooved test. Changes in an index of multi-finger force stabilizing synergy showed a significant correlation with changes in the index of force variability in the accurate force production test. Strong transfer effects were seen to the site that did not perform strength training exercise within each hand. Effects of exercise at the proximal site were somewhat stronger compared with those of exercise at the finger tips, although the differences did not reach significance level. Control tests showed that repetitive testing by itself did not significantly change the maximal finger force and enslaving. The results suggest that strength training is an effective way to improve finger strength. It can also lead to changes in finger interaction and in performance of accurate force production tasks. Adaptations at a neural level are likely to mediate the observed effects. Overall, the data suggest that strength training can also improve the hand function of less healthy elderly subjects. PMID:18687981

  2. Converging finite-strength shocks

    NASA Astrophysics Data System (ADS)

    Axford, R. A.; Holm, D. D.

    1981-01-01

    The converging shock problem was first solved by Guderley and later by Landau and Stanyukovich for infinitely strong shocks in an ideal gas with spherical and cylindrical symmetry. This problem is solved herein for finite-strength shocks and a non-ideal-gas equation of state with an adiabatic bulk modulus of the type Bs= {- v∂ p}/{∂ v| s} = ( p +B) f( v) , where B is a constant with the dimensions of pressure, and f(v) is an arbitrary function of the specific volume. Self-similar profiles of the particle velocity and thermodynamic variables are studied explicitly for two cases with constant specific heat at constant volume; the Tait-Kirkwood-Murnaghan equation, f(v) = constant, and the Walsh equation, f(v) = v/A, where A = constant. The first case reduces to the ideal gas when B = 0. In both cases the flow behind the shock front exhibits an unbalanced buoyant force instability at a critical Mach number which depends upon equation-of-state parameters.

  3. Strength Training for Young Athletes.

    ERIC Educational Resources Information Center

    Kraemer, William J.; Fleck, Steven J.

    This guide is designed to serve as a resource for developing strength training programs for children. Chapter 1 uses research findings to explain why strength training is appropriate for children. Chapter 2 explains some of the important physiological concepts involved in children's growth and development as they apply to developing strength…

  4. Strength properties of fly ash based controlled low strength materials.

    PubMed

    Türkel, S

    2007-08-25

    Controlled low strength material (CLSM) is a flowable mixture that can be used as a backfill material in place of compacted soils. Flowable fill requires no tamping or compaction to achieve its strength and typically has a load carrying capacity much higher than compacted soils, but it can still be excavated easily. The selection of CLSM type should be based on technical and economical considerations for specific applications. In this study, a mixture of high volume fly ash (FA), crushed limestone powder (filler) and a low percentage of pozzolana cement have been tried in different compositions. The amount of pozzolana cement was kept constant for all mixes as, 5% of fly ash weight. The amount of mixing water was chosen in order to provide optimum pumpability by determining the spreading ratio of CLSM mixtures using flow table method. The shear strength of the material is a measure of the materials ability to support imposed stresses on the material. The shear strength properties of CLSM mixtures have been investigated by a series of laboratory tests. The direct shear test procedure was applied for determining the strength parameters Phi (angle of shearing resistance) and C(h) (cohesion intercept) of the material. The test results indicated that CLSM mixtures have superior shear strength properties compared to compacted soils. Shear strength, cohesion intercept and angle of shearing resistance values of CLSM mixtures exceeded conventional soil materials' similar properties at 7 days. These parameters proved that CLSM mixtures are suitable materials for backfill applications.

  5. Strength Asymmetry of the Shoulders in Elite Volleyball Players

    PubMed Central

    Hadzic, Vedran; Sattler, Tine; Veselko, Matjaž; Markovic, Goran; Dervisevic, Edvin

    2014-01-01

    Context: Volleyball players are reported to have shoulder strength imbalances. Previous authors have primarily investigated small samples of male players at a single skill level, without considering playing position, and with inconsistent findings. Objective: To evaluate shoulder strength asymmetry and a history of shoulder injury in a large sample of professional volleyball players of both sexes across different playing positions and skill levels. Design: Descriptive laboratory study. Patients or Other Participants: A sample of 183 volleyball players (99 men, 84 women). Main Outcome Measure(s): We assessed shoulder internal-rotator and external-rotator concentric strength at 60°/s using an isokinetic dynamometer and dominant-nondominant differences in shoulder strength and strength ratios using repeated-measures analyses of variance. Peak torque was normalized for body mass and external-rotation/internal-rotation concentric strength. Results: Internal-rotation strength was asymmetric in favor of the dominant side in both sexes, regardless of previous shoulder injury status. Male volleyball players had a lower shoulder strength ratio on the dominant side, regardless of previous shoulder injury status. However, this finding was valid only when hand dominance was taken into account. Female volleyball players playing at a higher level (ie, first versus second division) were 3.43 times more likely to have an abnormal strength ratio. Playing position was not associated with an abnormal shoulder strength ratio or strength asymmetry. Conclusions: In male volleyball players, the external-rotation/internal-rotation strength ratio of the dominant shoulder was lower, regardless of playing position, skill level, or a previous shoulder injury. In female players, the ratio was less only in those at a higher skill level. Although speculative, these findings generally suggest that female volleyball players could have a lower risk of developing shoulder-related problems than male

  6. New Accurate Oscillator Strengths and Electron Excitation Collision Strengths for N1

    NASA Technical Reports Server (NTRS)

    Tayal, S. S.

    2006-01-01

    The nonorthogonal orbitals technique in a multiconfiguration Hartree-Fock approach is used to calculate oscillator strengths and transition probabilities of N(I) lines. The relativistic effects are allowed by means of Breit-Pauli operators. The length and velocity forms of oscillator strengths show good agreement for most transitions. The B-spline R-matrix with pseudostates approach has been used to calculate electron excitation collision strengths and rates. The nonorthogonal orbitals are used for an accurate description of both target wave functions and the R-matrix basis functions. The 24 spectroscopic bound and autoionizing states together with 15 pseudostates are included in the close-coupling expansion. The collision strengths for transitions between fine-structure levels are calculated by transforming the LS-coupled K-matrices to K-matrices in an intermediate coupling scheme. Thermally averaged collision strengths have been determined by integrating collision strength over a Maxwellian distribution of electron energies over a temperature range suitable for the modeling of astrophysical plasmas. The oscillator strengths and thermally averaged collision strengths are presented for transitions between the fine-structure levels of the 2s(sup 2)p(sup 3) (sup 4)S(sup 0), (sup 2)D(sup 0), (sup 2)P(sup 0), 2s2p(sup 4) (sup 4)P, 2s(sup 2)2p(sup 2)3s (sup 4)P, and (sup 2)P terms and from these levels to the levels of the 2s(sup 2)2p(sup 2)3p (sup 2)S(sup 0), (sup 4)D(sup 0), (sup 4)P(sup 0), (sup 4)S(sup 0), (sup 2)D(sup 0), (sup 2)P(sup 0),2s(sup 2)2p(sup 2)3s(sup 2)D, 2s(sup 2)2p(sup 2)4s(sup 4)P, (sup 2)P, 2s(sup 2)2p(sup 2)3d(sup 2)P, (sup 4)F,(sup 2)F,(sup 4)P, (sup 4)D, and (sup 2)D terms. Thermally averaged collision strengths are tabulated over a temperature range from 500 to 50,000 K.

  7. Aluminum Rayleigh Taylor Strength Measurements and Calculations

    SciTech Connect

    Lindquist, M J; Cavallo, R M; Lorenz, K T; Pollaine, S M; Remington, B A; Raevsky, V A

    2007-01-10

    A traditional approach to the study of material strength has been revitalized at the Russian Federal Nuclear Center (VNIIEF). Rayleigh Taylor strength experiments have long been utilized to measure the material response of metals at high pressure and strain rates. A modulated (sinusoidal or sawtooth perturbation) surface is shocklessly (quasi-isentropically) accelerated by a high explosive (HE) driver, and radiography is used to measure the perturbation amplitude as a function of time. The Aluminum T-6061 targets are designed with several sets of two-dimensional sawtooth perturbations machined on the loading surface. The HE driver was designed to reach peak pressures in the range of 200 to 300 kbar and strain rates in the range of 10{sup 4} - 10{sup 6} s{sup -1}. The standard constitutive strength models, Steinberg-Guinan (SG) [1], Steinberg-Lund (SL) [2], Preston-Tonks-Wallace (PTW) [3], Johnson-Cooke (JC) [4], and Mechanical Threshold Stress (MTS) [5], have been calibrated by traditional techniques: (Hopkinson-Bar, Taylor impact, flyer plate/shock-driven experiments). The VNIIEF experimental series accesses a strain rate regime not attainable using traditional methods. We have performed a detailed numerical study with a two-dimensional Arbitrary Lagrangian Eulerian hydrodynamics computer code containing several constitutive strength models to predict the perturbation growth. Results show that the capabilities of the computational methodology predict the amplitude growth to within 5 percent of the measured data, thus validating both the code and the strength models under the given conditions and setting the stage for credible future design work using different materials.

  8. High-resolution study of the Be9(He3,t)B9 reaction up to the B9 triton threshold

    NASA Astrophysics Data System (ADS)

    Scholl, C.; Fujita, Y.; Adachi, T.; von Brentano, P.; Fujita, H.; Górska, M.; Hashimoto, H.; Hatanaka, K.; Matsubara, H.; Nakanishi, K.; Ohta, T.; Sakemi, Y.; Shimbara, Y.; Shimizu, Y.; Tameshige, Y.; Tamii, A.; Yosoi, M.; Zegers, R. G. T.

    2011-07-01

    A high-energy-resolution Be9(He3,t)B9 charge-exchange reaction was performed around a scattering angle of 0° and at an intermediate incident energy of 140 MeV/nucleon for the study of precise Gamow-Teller (GT) transition strengths. The energy resolution of 30 keV allowed a precise deconvolution of the spectrum and the determination of angular distributions of cross sections, excitation energies, and decay widths. The GT strength of 10 states has been determined for the first time using the GT strength of the analogous β decays of Li9 and C9 as standards. The large difference between the GT strengths going to the low-lying T=1/2 and the highly excited T=3/2 states is interpreted as a result of their different spatial structures. The obtained GT strength distribution is compared to the results of a (p,n) experiment with lower resolution performed in the 1980s. In particular, the width of the 16.8 MeV, Jπ=(5/2+) state has been determined for the first time.

  9. Compressive strength of carbon fibers

    SciTech Connect

    Prandy, J.M. ); Hahn, H.T. )

    1991-01-01

    Most composites are weaker in compression than in tension, which is due to the poor compressive strength of the load bearing fibers. The present paper discusses the compressive strengths and failure modes of 11 different carbon fibers: PAN-AS1, AS4, IM6, IM7, T700, T300, GY-30, pitch-75, ultra high modulus (UHM), high modulus (HM), and high strength (HS). The compressive strength was determined by embedding a fiber bundle in a transparent epoxy matrix and testing in compression. The resin allows for the containment and observation of failure during and after testing while also providing lateral support to the fibers. Scanning electron microscopy (SEM) was used to determine the global failure modes of the fibers.

  10. Alterations in grip strength during male sexual arousal.

    PubMed

    Jiao, C; Turman, B; Weerakoon, P; Knight, P

    2006-01-01

    Although it is known that alterations in grip strength occur under a number of conditions, little is known about relationships between grip strength and sexual arousal. This relationship was investigated in 30 healthy heterosexual males, who viewed both erotic and nonerotic videos. A questionnaire was used to assess the extent of sexual arousal. The grip strengths of both hands were measured with a five-position (P1-P5) dynamometer, before and after watching the videos. After watching the erotic video, there was a statistically significant reduction in grip strength for the P2 position, with nonsignificant overall reductions in grip strength for all other positions tested. No such effect was observed in control tests. The results indicate that during sexual arousal, the neural system is likely to reduce the output to muscles not directly related to sexual function, presumably to enhance the physiological responses of sexual arousal. PMID:16254571

  11. Notched strength of beryllium powder and ingot sheets.

    NASA Technical Reports Server (NTRS)

    Moss, R. G.

    1972-01-01

    The effects of notches in thin beryllium sheets were studied as functions of material variables and notch severity. Double edge notched samples having stress concentration factors of 1.0 to 15.4 were prepared by milling to size, etching, and electrical discharge machining the notches. Strength was not reduced greatly by sharp notches, and duller notches were more deleterious than sharp notches. The trend was for reduced strength for dull notches, increased strength for sharper notches, and reduced strength for very sharp notches. Differences in material purity or source of the sheet had little affect on notch sensitivity. The most important factors appear to be oxide content and directionality of the sheet microstructure; high oxide content and highly directional microstructure tend to give more notch sensitivity than low oxide content, and more bidirectional microstructure. Postulated causes of the change in notched/unnotched strength are given.

  12. Enhancement of octupole strength in near spherical nuclei

    NASA Astrophysics Data System (ADS)

    Robledo, L. M.

    2016-09-01

    The validity of the rotational formula used to compute E1 and E3 transition strengths in even-even nuclei is analyzed within the Generator Coordinate Method framework based on mean field wave functions. It turns out that those nuclei with spherical or near spherical shapes the E1 and E3 strengths computed with this formula are strongly underestimated and a sound evaluation of them requires angular-momentum projected wave functions. Results for several isotopic chains with proton number equal to or near magic numbers are analyzed and compared with experimental data. The use of angular-momentum projected wave functions greatly improves the agreement with the scarce experimental data.

  13. Isospin and spin-isospin modes in charge-exchange reactions

    SciTech Connect

    Harakeh, M. N.; Berg, A. M. van den; Brandenburg, S.; Zegers, R. G. T.; Akimune, H.; Fujiwara, M.; Laurent, H.; Willis, A.

    1999-11-16

    The microscopic structure of the Gamow-Teller resonance (GTR) and spin-dipole resonance (SDR) in {sup 208}Bi has been investigated in the {sup 208}Pb({sup 3}He,tp){sup 207}Pb reaction at E({sup 3}He)=450 MeV and very forward scattering angles. The partial and total branching ratios and the escape widths for GTR and SDR decay to the residual neutron-hole states in {sup 207}Pb were deduced. These are found to be in good agreement with recent theoretical estimates. The ({sup 3}He,tp) reaction on Pb at E({sup 3}He)=177 MeV was also studied in order to locate isovector monopole strength corresponding to 2({Dirac_h}/2{pi}){omega} transitions. Monopole strength at excitation energies above 25 MeV was discovered and compared to calculated strength due to the isovector giant monopole resonance and the spin-flip isovector monopole resonance. Calculations in a normal-mode framework show that all isovector monopole strength can be accounted for if the branching ratio for decay by proton emission is 20%.

  14. Isospin and Spin-Isospin Modes in Charge-Exchange Reactions

    SciTech Connect

    Harakeh, M.N.; Akimune, H.; van den Berg, A.M.; Brandenburg, S.; Fujiwara, M.; Laurent, H.; Willis, A.; Zegers, R.G.T.

    1999-12-31

    The microscopic structure of the Gamow-Teller resonance (GTR) and spin-dipole resonance (SDR) in {sup 208}Bi has been investigated in the {sup 208}Pb({sup 3}He,tp){sup 207}Pb reaction at E{sup 3}He=450 MeV and very forward scattering angles. The partial and total branching ratios and the escape widths for GTR and SDR decay to the residual neutron-hole states in {sup 207}Pb were deduced. These are found to be in good agreement with recent theoretical estimates. The ({sup 3}He,tp) reaction on Pb at E({sup 3}He)=177 MeV was also studied in order to locate isovector monopole strength corresponding to 2{Dirac_h}{omega} transitions. Monopole strength at excitation energies above 25 MeV was discovered and compared to calculated strength due to the isovector giant monopole resonance and the spin-flip isovector monopole resonance. Calculations in a normal-mode framework show that all isovector monopole strength can be accounted for if the branching ratio for decay by proton emission is 20%.

  15. Neutrino-nucleus reactions based on recent structure studies

    SciTech Connect

    Suzuki, Toshio

    2015-05-15

    Neutrino-nucleus reactions are studied with the use of new shell model Hamiltonians, which have proper tensor components in the interactions and prove to be successful in the description of Gamow-Teller (GT) strengths in nuclei. The new Hamiltonians are applied to obtain new neutrino-nucleus reaction cross sections in {sup 12}C, {sup 13}C, {sup 56}Fe and {sup 56}Ni induced by solar and supernova neutrinos. The element synthesis by neutrino processes in supernova explosions is discussed with the new cross sections. The enhancement of the production yields of {sup 7}Li, {sup 11}B and {sup 55}Mn is obtained while fragmented GT strength in {sup 56}Ni with two-peak structure is found to result in smaller e-capture rates at stellar environments. The monopole-based universal interaction with tensor force of π+ρ meson exchanges is used to evaluate GT strength in {sup 40}Ar and ν-induced reactions on {sup 40}Ar. It is found to reproduce well the experimental GT strength in {sup 40}Ar.

  16. Probabilistic constitutive relationships for cyclic material strength models

    NASA Technical Reports Server (NTRS)

    Boyce, L.; Chamis, C. C.

    1988-01-01

    A methodology is developed that provides a probabilistic treatment for the lifetime of structural components of aerospace propulsion systems subjected to fatigue. Material strength degradation models, based on primitive variables, include both a fatigue strength reduction model and a fatigue crack growth model. Probabilistic analysis is based on simulation, and both maximum entropy and maximum penalized likelihood methods are used for the generation of probability density functions. The resulting constitutive relationships are included in several computer programs.

  17. Crystal strength by direct computation

    NASA Astrophysics Data System (ADS)

    Bulatov, Vasily

    2007-03-01

    The art of making materials stronger goes back to medieval and even ancient times. Swords forged from Damascus steels more than 10 centuries ago possessed a unique combination of hardness and flexibility, two qualities that are difficult to attain simultaneously. The skills of metalworking were based on empirical knowledge and were passed from the master smith to his pupils. The science of physical metallurgy came about only in the XX century bringing with it new methods for finding out why some materials are strong while others are not. Soon it was realized that, when it comes to metal strength, it is all about crystal defects -- impurities, dislocations, grain boundaries, etc. - and how they are organized into crystal microstructure. This understanding has since resulted in new effective methods of material processing aiming to modify crystal microstructure in order to affect material's properties, e.g. strength and/or hardness. Remarkably and disappointingly, general understanding that microstructure defines material's response to external loads has not yet resulted in a workable physical theory of metal strength accounting for the realistic complexity of material microstructure. In this presentation I would like to discuss a few tidbits from computational and experimental research in our group at LLNL on crystal defects and their contributions to material strength. My selection of the examples aims to illustrate the major premise of our work that the mechanisms by which the microstructure affects crystal strength are multiple and complex but that there is hope to bring some order to this complexity.

  18. Lifting strength in two-person teamwork.

    PubMed

    Lee, Tzu-Hsien

    2016-01-01

    This study examined the effects of lifting range, hand-to-toe distance, and lifting direction on single-person lifting strengths and two-person teamwork lifting strengths. Six healthy males and seven healthy females participated in this study. Two-person teamwork lifting strengths were examined in both strength-matched and strength-unmatched groups. Our results showed that lifting strength significantly decreased with increasing lifting range or hand-to-toe distance. However, lifting strengths were not affected by lifting direction. Teamwork lifting strength did not conform to the law of additivity for both strength-matched and strength-unmatched groups. In general, teamwork lifting strength was dictated by the weaker of the two members, implying that weaker members might be exposed to a higher potential danger in teamwork exertions. To avoid such overexertion in teamwork, members with significantly different strength ability should not be assigned to the same team.

  19. Strength of a bifurcated H bond

    PubMed Central

    Feldblum, Esther S.; Arkin, Isaiah T.

    2014-01-01

    Macromolecules are characterized by their particular arrangement of H bonds. Many of these interactions involve a single donor and acceptor pair, such as the regular H-bonding pattern between carbonyl oxygens and amide H+s four residues apart in α-helices. The H-bonding potential of some acceptors, however, leads to the phenomenon of overcoordination between two donors and one acceptor. Herein, using isotope-edited Fourier transform infrared measurements and density functional theory (DFT) calculations, we measured the strength of such bifurcated H bonds in a transmembrane α-helix. Frequency shifts of the 13C=18O amide I mode were used as a reporter of the strength of the bifurcated H bond from a thiol and hydroxyl H+ at residue i + 4. DFT calculations yielded very similar frequency shifts and an energy of −2.6 and −3.4 kcal/mol for the thiol and hydroxyl bifurcated H bonds, respectively. The strength of the intrahelical bifurcated H bond is consistent with its prevalence in hydrophobic environments and is shown to significantly impact side-chain rotamer distribution. PMID:24591597

  20. Selective Activation of Microglia Facilitates Synaptic Strength

    PubMed Central

    Clark, Anna K.; Gruber-Schoffnegger, Doris; Drdla-Schutting, Ruth; Gerhold, Katharina J.; Malcangio, Marzia

    2015-01-01

    Synaptic plasticity is thought to be initiated by neurons only, with the prevailing view assigning glial cells mere specify supportive functions for synaptic transmission and plasticity. We now demonstrate that glial cells can control synaptic strength independent of neuronal activity. Here we show that selective activation of microglia in the rat is sufficient to rapidly facilitate synaptic strength between primary afferent C-fibers and lamina I neurons, the first synaptic relay in the nociceptive pathway. Specifically, the activation of the CX3CR1 receptor by fractalkine induces the release of interleukin-1β from microglia, which modulates NMDA signaling in postsynaptic neurons, leading to the release of an eicosanoid messenger, which ultimately enhances presynaptic neurotransmitter release. In contrast to the conventional view, this form of plasticity does not require enhanced neuronal activity to trigger the events leading to synaptic facilitation. Augmentation of synaptic strength in nociceptive pathways represents a cellular model of pain amplification. The present data thus suggest that, under chronic pain states, CX3CR1-mediated activation of microglia drives the facilitation of excitatory synaptic transmission in the dorsal horn, which contributes to pain hypersensitivity in chronic pain states. PMID:25788673

  1. Stature is an essential predictor of muscle strength in children

    PubMed Central

    2012-01-01

    Background Children with growth retardation or short stature generally present with lower strength than children of the same chronological age. The aim of the study was to establish if strength was dependent on variables related to stature in a population of healthy children and to propose practical predictive models for the muscle functions tested. A secondary aim was to test for any learning effects concerning strength measured at two successive visits by children. Methods Hand grip, elbow flexion and extension, and knee flexion and extension were measured by fixed dynamometry in 96 healthy subjects (47 girls and 49 boys, aged from 5 to 17 years). Results For the present paediatric population, muscle strength was highly dependent on height. Predictive models are proposed for the muscle functions tested. No learning effect between the first and the second visit was detected for any of the muscle functions tested. Conclusions This work shows that strength measurements using fixed dynamometry are reliable in children when using appropriate standardization of operating procedures. It underlines the particular relationship between body stature and muscle strength. Predictive equations may help with assessing the neuromuscular involvement in children suffering from various disorders, particularly those affecting their stature. PMID:22989265

  2. The torsional strength of wings

    NASA Technical Reports Server (NTRS)

    Burgess, C P

    1930-01-01

    This report describes a simple method for calculating the position of the elastic axis of a wing structure having any number of spars. It is shown that strong drag bracing near the top and bottom of a wing greatly increases the torsional strength. An analytical procedure for finding the contribution of the drag bracing to the torsional strength and stiffness is described, based upon the principle of least work, and involving only one unknown quantity. A coefficient for comparing the torsional rigidity of different wings is derived in this report.

  3. Normative data for hand grip strength and key pinch strength, stratified by age and gender for a multiethnic Asian population

    PubMed Central

    Lam, Ngee Wei; Goh, Hui Ting; Kamaruzzaman, Shahrul Bahyah; Chin, Ai-Vyrn; Poi, Philip Jun Hua; Tan, Maw Pin

    2016-01-01

    INTRODUCTION Hand strength is a good indicator of physical fitness and frailty among the elderly. However, there are no published hand strength references for Malaysians aged > 65 years. This study aimed to establish normative data for hand grip strength (HGS) and key pinch strength (KPS) for Malaysians aged ≥ 60 years, and explore the relationship between hand strength and physical ability. METHODS Healthy participants aged ≥ 60 years with no neurological conditions were recruited from rural and urban locations in Malaysia. HGS and KPS were measured using hand grip and key pinch dynamometers. Basic demographic data, anthropometric measures, modified Barthel Index scores and results of the Functional Reach Test (FRT), Timed Up and Go (TUG) test and Jebsen-Taylor Hand Function Test (JTHFT) were recorded. RESULTS 362 subjects aged 60–93 years were recruited. The men were significantly stronger than the women in both HGS and KPS (p < 0.001). The hand strength of the study cohort was lower than that of elderly Western populations. Significant correlations were observed between hand strength, and residential area (p < 0.001), FRT (r = 0.236, p = 0.028), TUG (r = −0.227, p = 0.009) and JTHFT (r = −0.927, p < 0.001). CONCLUSION This study established reference ranges for the HGS and KPS of rural and urban elderly Malaysian subpopulations. These will aid the use of hand strength as a screening tool for frailty among elderly persons in Malaysia. Future studies are required to determine the modifiable factors for poor hand strength. PMID:26768064

  4. An interlaminar tension strength specimen

    NASA Technical Reports Server (NTRS)

    Jackson, Wade C.; Martin, Roderick H.

    1992-01-01

    This paper describes a technique to determine interlaminar tension strength, sigma(sub 3c) of a fiber reinforced composite material using a curved beam. The specimen was a unidirectional curved beam, bent 90 degrees, with straight arms. Attached to each arm was a hinged loading mechanism which was held by the grips of a tensile testing machine. Geometry effects of the specimen, including the effects of loading arm length, inner radius, thickness, and width, were studied. The data sets fell into two categories: low strength corresponding to a macroscopic flaw related failure and high strength corresponding to a microscopic flaw related failure. From the data available, the loading arm length had no effect on sigma(sub 3c). The inner radius was not expected to have a significant effect on sigma(sub 3c), but this conclusion could not be confirmed because of differences in laminate quality for each curve geometry. The thicker specimens had the lowest value of sigma(sub 3c) because of poor laminate quality. Width was found to affect the value of sigma(sub 3c) only slightly. The wider specimens generally had a slightly lower strength since more material was under high stress, and hence, had a larger probability of containing a significant flaw.

  5. Prepubescent Strength Training Gains Support.

    ERIC Educational Resources Information Center

    Duda, Marty

    1986-01-01

    Recent studies have stimulated greater support for prepubescent weight training. There seems to be general agreement that strength and weight training, when practiced under properly controlled conditions, is safe and efficacious for prepubescents. Weight lifting is not supported. Recommendations for weight training are made, and reservations are…

  6. Building Strengths through Adventure Education

    ERIC Educational Resources Information Center

    Loughmiller, Grover C.

    2007-01-01

    Campbell Loughmiller (1906-1993) is widely recognized as a leader in therapeutic work with troubled youngsters in outdoor settings. Rejecting punitive or institutional models of intervention, Loughmiller set out to demonstrate that every young person has strengths, desires to make positive changes, can grow in responsibility, and contribute to…

  7. Multi-Scale Effects in the Strength of Ceramics

    PubMed Central

    Cook, Robert F.

    2016-01-01

    Multiple length-scale effects are demonstrated in indentation-strength measurements of a range of ceramic materials under inert and reactive conditions. Meso-scale effects associated with flaw disruption by lateral cracking at large indentation loads are shown to increase strengths above the ideal indentation response. Micro-scale effects associated with toughening by microstructural restraints at small indentation loads are shown to decrease strengths below the ideal response. A combined meso-micro-scale analysis is developed that describes ceramic inert strength behaviors over the complete indentation flaw size range. Nano-scale effects associated with chemical equilibria and crack velocity thresholds are shown to lead to invariant minimum strengths at slow applied stressing rates under reactive conditions. A combined meso-micro-nano-scale analysis is developed that describes the full range of reactive and inert strength behaviors as a function of indentation load and applied stressing rate. Applications of the multi-scale analysis are demonstrated for materials design, materials selection, toughness determination, crack velocity determination, bond-rupture parameter determination, and prediction of reactive strengths. The measurements and analysis provide strong support for the existence of sharp crack tips in ceramics such that the nano-scale mechanisms of discrete bond rupture are separate from the larger scale crack driving force mechanics characterized by continuum-based stress-intensity factors. PMID:27563150

  8. A Strength Model and Service Envelope for PBX 9501

    SciTech Connect

    Stevens, Ralph

    2014-02-05

    An analytical method is proposed for making an assessment of the severity of the response of PBX 9501 in structural response simulations. The approach is based on the coherent use of a strength model and a failure criterion. The strength model is based on a creep rupture function and an associated cumulative damage model. The material's residual strength at any time during a simulation of structural response is determined by taking into account both the actual stress history up to that time, and a hypothetical continuation of the applied stresses that are assumed to grow until material failure results. The residual strength is used by the failure criterion to define the region of safe (non-failed) material response. The Mohr-Coulomb failure criterion is chosen for its general applicability to materials with both cohesive and frictional strength. The combined use of the residual strength model and the failure criterion provides a quantitative method of assessing the severity of the response of PBX 9501 material in structural simulations: the proximity of any evolving, general state of stress to the failure surface (which shrinks due to the cumulative damage caused by the past stress history) can be calculated and used as a measure of margin to failure. The strength model has been calibrated to a broad range of uniaxial tension and compression tests, and a small set of creep tests, and is applicable to a broad range of loading conditions.

  9. Trunk Stability, Trunk Strength and Sport Performance Level in Judo

    PubMed Central

    Barbado, David; Lopez-Valenciano, Alejandro; Juan-Recio, Casto; Montero-Carretero, Carlos; van Dieën, Jaap H.; Vera-Garcia, Francisco J.

    2016-01-01

    Although trunk muscle function has been suggested to be a determinant of judo performance, its contribution to high-level performance in this sport has been poorly studied. Therefore, several tests were used to assess the differences in trunk muscle function between 11 international and 14 national level judo practitioners (judokas). Trunk strength and endurance were assessed using isokinetic tests and core stability was assessed using two protocols: 1) sudden loading, to assess trunk responses to unexpected external perturbations; 2) stable and unstable sitting, to assess the participants’ ability to control trunk balance. No differences between groups were found for trunk flexor isokinetic strength, trunk responses against lateral and posterior loading and trunk control while sitting. However, international level judokas showed significantly higher trunk extensor isokinetic strength (p <0.05) and lower trunk angular displacement after anterior trunk loading (p <0.05) than national level judokas. Few and low (r < 0.512) significant correlations were found between strength, endurance and stability parameters, which suggests that trunk strength and endurance are not limiting factors for trunk stability in competitive judokas. These results support the importance of trunk extensor strength and trunk stability against forward perturbations in elite judo performance. PMID:27232602

  10. Trunk Stability, Trunk Strength and Sport Performance Level in Judo.

    PubMed

    Barbado, David; Lopez-Valenciano, Alejandro; Juan-Recio, Casto; Montero-Carretero, Carlos; van Dieën, Jaap H; Vera-Garcia, Francisco J

    2016-01-01

    Although trunk muscle function has been suggested to be a determinant of judo performance, its contribution to high-level performance in this sport has been poorly studied. Therefore, several tests were used to assess the differences in trunk muscle function between 11 international and 14 national level judo practitioners (judokas). Trunk strength and endurance were assessed using isokinetic tests and core stability was assessed using two protocols: 1) sudden loading, to assess trunk responses to unexpected external perturbations; 2) stable and unstable sitting, to assess the participants' ability to control trunk balance. No differences between groups were found for trunk flexor isokinetic strength, trunk responses against lateral and posterior loading and trunk control while sitting. However, international level judokas showed significantly higher trunk extensor isokinetic strength (p <0.05) and lower trunk angular displacement after anterior trunk loading (p <0.05) than national level judokas. Few and low (r < 0.512) significant correlations were found between strength, endurance and stability parameters, which suggests that trunk strength and endurance are not limiting factors for trunk stability in competitive judokas. These results support the importance of trunk extensor strength and trunk stability against forward perturbations in elite judo performance. PMID:27232602

  11. The Strength-Based Counseling Model

    ERIC Educational Resources Information Center

    Smith, Elsie J.

    2006-01-01

    This article proposes a strength-based model for counseling at-risk youth. The author presents the assumptions, basic concepts, and values of the strength perspective in counseling and offers strength categories as a conceptual model for viewing clients' behavior. Propositions leading toward a theory of strength-based counseling and stages of this…

  12. Associations between personality traits, physical activity level, and muscle strength.

    PubMed

    Tolea, Magdalena I; Terracciano, Antonio; Simonsick, Eleanor M; Metter, E Jeffrey; Costa, Paul T; Ferrucci, Luigi

    2012-06-01

    Associations among personality as measured by the Five Factor Model, physical activity, and muscle strength were assessed using data from the Baltimore Longitudinal Study of Aging (N = 1220, age: mean = 58, SD = 16). General linear modeling with adjustment for age, sex, race, and body mass index, and bootstrapping for mediation were used. We found neuroticism and most of its facets to negatively correlate with strength. The extraversion domain and its facets of warmth, activity, and positive-emotions were positively correlated with strength, independent of covariates. Mediation analysis results suggest that these associations are partly explained by physical activity level. Findings extend the evidence of an association between personality and physical function to its strength component and indicate health behavior as an important pathway. PMID:23966753

  13. Polyimide films from vapor deposition: toward high strength, NIF capsules

    SciTech Connect

    Cook, R C; Hsieh, E J; Letts, S A; Roberts, C C; Saculla, M

    1998-10-16

    The focus of recent efforts at LLNL has been to demonstrate that vapor deposition processing is a suitable technique to form polyimide fnms with sufficient strength for current national ignition facility target specifications. Production of polyimide films with controlled stoichiometry was acccomplished by: 1) depositing a novel co-functional monomer and 2) matching the vapor pressure of each monomer in PMDA/ODA co-depositions. The sublimation and deposition rate for the monomers was determined over a range of temperatures. Polyimide films with thicknesses up to 30 p.m were fabricated. Composition, structure and strength were assessed using FTIR, SEM and biaxial burst testing. The best films had a tensile strength of approximately 100 MPa. A qualitative relationship between the stoichiometry and tensile strength of the film was demonstrated. Thin films ({approximately}3.5 {micro}m) were typically smooth with an rms of 1.5 nm.

  14. Associations between personality traits, physical activity level, and muscle strength.

    PubMed

    Tolea, Magdalena I; Terracciano, Antonio; Simonsick, Eleanor M; Metter, E Jeffrey; Costa, Paul T; Ferrucci, Luigi

    2012-06-01

    Associations among personality as measured by the Five Factor Model, physical activity, and muscle strength were assessed using data from the Baltimore Longitudinal Study of Aging (N = 1220, age: mean = 58, SD = 16). General linear modeling with adjustment for age, sex, race, and body mass index, and bootstrapping for mediation were used. We found neuroticism and most of its facets to negatively correlate with strength. The extraversion domain and its facets of warmth, activity, and positive-emotions were positively correlated with strength, independent of covariates. Mediation analysis results suggest that these associations are partly explained by physical activity level. Findings extend the evidence of an association between personality and physical function to its strength component and indicate health behavior as an important pathway.

  15. Levator plate upward lift and levator muscle strength

    PubMed Central

    Rostaminia, Ghazaleh; Peck, Jennifer; Quiroz, Lieschen; Shobeiri, S. Abbas

    2016-01-01

    Objective The aim of study was to compare digital palpation with the levator plate lift measured by endovaginal and transperineal dynamic ultrasound. Methods Dynamic transperineal and endovaginal ultrasound were performed as part of multicompartmental pelvic floor functional assessment. Patients were instructed to perform Kegels while a probe captured the video clip of the levator plate movement at rest and during contraction in 2D mid-sagittal posterior view. We measured the distance between the levator plate and the probe on endovaginal ultrasound as well as the distance between the levator plate and the gothic arch of the pubis in transperineal ultrasound. The change in diameter (lift) and a levator plate lift ratio (lift / rest) x 100) were calculated. Pelvic floor muscle strength was assessed by digital palpation and divided into functional and non-functional groups using the Modified Oxford Scale (MOS). Mean differences in levator plate upward lifts were compared by MOS score using student t-tests and analysis of variance (ANOVA). Results 74 women were available for analysis. The mean age was 55 (SD±11.9). When measured by vaginal dynamic ultrasound, mean values of the lift and lift/rest ratio increased with increasing MOS score (ANOVA p=0.09 and p=0.04, respectively). When MOS scores were categorized to represent non-functional (MOS 0-1) and functional (MOS 2-5) muscle strength groups, the mean values of the lift (3.2 mm vs. 4.6 mm, p=0.03) and lift/rest ratio (13% vs 20%, p=0.01) were significantly higher in women with functional muscle strength. All patients with ≥ 30% lift detected by vaginal ultrasound had functional muscle strength. Conclusions Greater levator plate lift ratio detected by dynamic endovaginal ultrasound was associated with higher muscle strength as determined by MOS. This novel measurement can be incorporated into ultrasound evaluation of the levator ani function. PMID:26333568

  16. Grip Strength Cutpoints for the Identification of Clinically Relevant Weakness

    PubMed Central

    Shardell, Michelle D.; Peters, Katherine W.; McLean, Robert R.; Dam, Thuy-Tien L.; Kenny, Anne M.; Fragala, Maren S.; Harris, Tamara B.; Kiel, Douglas P.; Guralnik, Jack M.; Ferrucci, Luigi; Kritchevsky, Stephen B.; Studenski, Stephanie A.; Vassileva, Maria T.; Cawthon, Peggy M.

    2014-01-01

    Background. Weakness is common and contributes to disability, but no consensus exists regarding a strength cutpoint to identify persons at high risk. This analysis, conducted as part of the Foundation for the National Institutes of Health Sarcopenia Project, sought to identify cutpoints that distinguish weakness associated with mobility impairment, defined as gait speed less than 0.8 m/s. Methods. In pooled cross-sectional data (9,897 men and 10,950 women), Classification and Regression Tree analysis was used to derive cutpoints for grip strength associated with mobility impairment. Results. In men, a grip strength of 26–32 kg was classified as “intermediate” and less than 26 kg as “weak”; 11% of men were intermediate and 5% were weak. Compared with men with normal strength, odds ratios for mobility impairment were 3.63 (95% CI: 3.01–4.38) and 7.62 (95% CI 6.13–9.49), respectively. In women, a grip strength of 16–20 kg was classified as “intermediate” and less than 16 kg as “weak”; 25% of women were intermediate and 18% were weak. Compared with women with normal strength, odds ratios for mobility impairment were 2.44 (95% CI 2.20–2.71) and 4.42 (95% CI 3.94–4.97), respectively. Weakness based on these cutpoints was associated with mobility impairment across subgroups based on age, body mass index, height, and disease status. Notably, in women, grip strength divided by body mass index provided better fit relative to grip strength alone, but fit was not sufficiently improved to merit different measures by gender and use of a more complex measure. Conclusions. Cutpoints for weakness derived from this large, diverse sample of older adults may be useful to identify populations who may benefit from interventions to improve muscle strength and function. PMID:24737558

  17. Extreme rapid warming yields high functional survivals of vitrified 8-cell mouse embryos even when suspended in a half-strength vitrification solution and cooled at moderate rates to −196°C✰

    PubMed Central

    Seki, Shinsuke; Jin, Bo; Mazu, Peter

    2014-01-01

    To cryopreserve cells, it is essential to avoid intracellular ice formation during cooling and warming. One way to do so is to subject them to procedures that convert cell water into a non-crystalline glass. Current belief is that to achieve this vitrification, cells must be suspended in very high concentrations of glass-inducing solutes (i.e., ≥ 6 molal) and cooled at very high rates (i.e., >> 1,000°C/min). We report here that both these beliefs are incorrect with respect to the vitrification of 8-cell mouse embryos. In this study, precompaction 8-cell embryos were vitrified in several dilutions of EAFS10/10 using various cooling rates and warming rates. Survival was based on morphology, osmotic functionality, and on the ability to develop to expanded blastocysts. With a warming rate of 117,500°C/min, the percentages of embryos vitrified in 1×, 0.75×, and 0.5× EAFS that developed to blastocysts were 93%, 92%, and 86%, respectively. And the percentages of morphological survivors that developed to expanded blastocysts were 100%, 92%, and 97%, respectively. Even when the solute concentration of the EAFS was reduced to 33% of normal, we obtained 40% functional survival of these 8-cell embryos. PMID:24333434

  18. Strength Scaling in Fiber Composites

    NASA Technical Reports Server (NTRS)

    Kellas, Sotiris; Morton, John

    1990-01-01

    A research program was initiated to study and isolate the factors responsible for scale effects in the tensile strength of graphite/epoxy composite laminates. Four layups were chosen with appropriate stacking sequences so as to highlight individual and interacting failure modes. Four scale sizes were selected for investigation including full scale size, 3/4, 2/4, and 1/4, with n = to 4, 3, 2, and 1, respectively. The full scale specimen sizes was 32 piles thick as compared to 24, 16, and 8 piles for the 3/4, 2/4, and 1/4 specimen sizes respectively. Results were obtained in the form of tensile strength, stress-strain curves and damage development. Problems associated with strength degradation with increasing specimen sizes are isolated and discussed. Inconsistencies associated with strain measurements were also identified. Enhanced x ray radiography was employed for damage evaluation, following step loading. It was shown that fiber dominated layups were less sensitive to scaling effects compared to the matrix dominated layups.

  19. An Interlaminar Tensile Strength Specimen

    NASA Technical Reports Server (NTRS)

    Martin, Roderick H.; Jackson, Wade C.

    1993-01-01

    This paper describes a technique to determine interlaminar tensile strength, sigma(sub 3c), of a fiber reinforced composite material using a curved beam. The specimen was a unidirectional curved beam, bent 90 deg, with straight arms. Attached to each arm was a hinged loading mechanism that was held by the grips of a tension testing machine. Geometry effects of the specimen, including the effects of loading arm length, inner radius, thickness, and width, were studied. The data sets fell into two categories: low strength corresponding to a macroscopic flaw related failure and high strength corresponding to a microscopic flaw related failure. From the data available, the specimen width and loading arm length had little effect on sigma(sub 3c). The inner radius was not expected to have a significant effect on sigma(sub 3c), but this conclusion could not be confirmed because of differences in laminate quality for each curve geometry. The thicker specimens had the lowest value of sigma(sub 3c) because of poor laminate quality.

  20. Mechanical strength of trabecular bone at the knee.

    PubMed

    Hvid, I

    1988-08-01

    Interest in the biomechanical properties of trabecular bone has expanded in response to the problems related to total and partial joint replacement with the knee joint constituting a main focus of attention. This relatively recent development has left a number of fundamental problems unanswered, especially related to the machining, storage and testing of trabecular bone specimens. Nevertheless, these studies have contributed to the understanding of the mechanical function of trabecular bone. Regarding the role of trabecular bone at the knee joint, the following conclusions may be emphasized (conclusions drawn from the author's previous studies (I-X) are shown in italics): (1) Trabecular bone is almost exclusively responsible for the transmission of load at the proximal tibial epiphysis from the knee joint to the metaphysis. The peripheral shell surrounding the epiphysis is not composed of cortical bone and plays a negligible role in load transmission. (2) The compressive strength and stiffness of trabecular bone is primarily dependent upon the apparent density, trabecular architecture and the strength of the bone material. Direct and indirect sources suggest that the true material strength of trabecular bone is less than that of cortical bone. The epiphyseal trabecular architecture, featuring a marked polarity with alignment of primary trabeculae at right angles to the joint surface, is responsible for functional anisotropy which points to the axial compressive properties as the more important mechanical parameters. (3) Tensile and shear properties are of special relevance to mechanical loosening of implants. These properties may be derived from the apparent density, and a close empirical relation to the axial compressive strength and stiffness is suggested. (4) The foam-like structure of trabecular bone is the basis for the large energy absorptive capacity. (5) The pattern of axial compressive stiffness and strength at the normal proximal tibia differs little

  1. Nuclear response theory for spin-isospin excitations in a relativistic quasiparticle-phonon coupling framework

    NASA Astrophysics Data System (ADS)

    Robin, Caroline; Litvinova, Elena

    2016-07-01

    A new theoretical approach to spin-isospin excitations in open-shell nuclei is presented. The developed method is based on the relativistic meson-exchange nuclear Lagrangian of Quantum Hadrodynamics and extends the response theory for superfluid nuclear systems beyond relativistic quasiparticle random phase approximation in the proton-neutron channel (pn-RQRPA). The coupling between quasiparticle degrees of freedom and collective vibrations (phonons) introduces a time-dependent effective interaction, in addition to the exchange of pion and ρ -meson taken into account without retardation. The time-dependent contributions are treated in the resonant time-blocking approximation, in analogy to the previously developed relativistic quasiparticle time-blocking approximation (RQTBA) in the neutral (non-isospin-flip) channel. The new method is called proton-neutron RQTBA (pn-RQTBA) and is applied to the Gamow-Teller resonance in a chain of neutron-rich nickel isotopes 68-78Ni . A strong fragmentation of the resonance along with quenching of the strength, as compared to pn-RQRPA, is obtained. Based on the calculated strength distribution, beta-decay half-lives of the considered isotopes are computed and compared to pn-RQRPA half-lives and to experimental data. It is shown that a considerable improvement of the half-life description is obtained in pn-RQTBA because of the spreading effects, which bring the lifetimes to a very good quantitative agreement with data.

  2. Modification of magicity toward the dripline and its impact on electron-capture rates for stellar core collapse

    NASA Astrophysics Data System (ADS)

    Raduta, Ad. R.; Gulminelli, F.; Oertel, M.

    2016-02-01

    The importance of microphysical inputs from laboratory nuclear experiments and theoretical nuclear structure calculations in the understanding of core-collapse dynamics and the subsequent supernova explosion is largely recognized in the recent literature. In this work, we analyze the impact of the masses of very neutron-rich nuclei on the matter composition during collapse and the corresponding electron-capture rate. To this end, we introduce an empirical modification of the popular Duflo-Zuker mass model to account for possible shell quenching far from stability. We study the effect of this quenching on the average electron-capture rate. We show that the pre-eminence of the closed shells with N =50 and N =82 in the collapse dynamics is considerably decreased if the shell gaps are reduced in the region of 78Ni and beyond. As a consequence, local modifications of the overall electron-capture rate of up to 30% can be expected, depending on the strength of magicity quenching. This finding has potentially important consequences on the entropy generation, the neutrino emissivity, and the mass of the core at bounce. Our work underlines the importance of new experimental measurements in this region of the nuclear chart, the most crucial information being the nuclear mass and the Gamow-Teller strength. Reliable microscopic calculations of the associated elementary rate, in a wide range of temperatures and electron densities, optimized on these new empirical information, will be additionally needed to get quantitative predictions of the collapse dynamics.

  3. Studies on the double-{beta} decay nucleus {sup 64}Zn using the (d,{sup 2}He) reaction

    SciTech Connect

    Grewe, E.-W.; Baeumer, C.; Dohmann, H.; Frekers, D.; Hollstein, S.; Rakers, S.; Thies, J. H.; Harakeh, M. N.; Berg, A. M. van den; Woertche, H. J.; Johansson, H.; Martinez-Pinedo, G.; Petermann, I.; Sieja, K.; Simon, H.; Langanke, K.; Nowacki, F.; Popescu, L.; Savran, D.; Zilges, A.

    2008-06-15

    The (d,{sup 2}He) charge-exchange reaction on the double-{beta} decay ({beta}{beta}) nucleus {sup 64}Zn has been studied at an incident energy of 183 MeV. The two protons in the {sup 1}S{sub 0} state (indicated as {sup 2}He) were both momentum analyzed and detected simultaneously by the BBS magnetic spectrometer and its position-sensitive detector. {sup 2}He spectra with a resolution of about 115 keV (FWHM) have been obtained allowing identification of many levels in the residual nucleus {sup 64}Cu with high precision. {sup 64}Zn is one of the rare cases undergoing a {beta}{beta} decay in {beta}{sup +} direction. In the experiment presented here, Gamow-Teller (GT{sup +}) transition strengths have been extracted. Together with the GT{sup -} transition strengths from {sup 64}Ni({sup 3}He,t) data to the same intermediate nucleus {sup 64}Cu, the nuclear matrix elements of the {beta}{beta} decay of {sup 64}Zn have been evaluated. Finally, the GT{sup {+-}} distributions are compared with shell-model calculations and a critical assessment is given of the various residual interactions presently employed for the pf shell.

  4. High energy-resolution measurement of the 82Se(3He,t )82Br reaction for double-β decay and for solar neutrinos

    NASA Astrophysics Data System (ADS)

    Frekers, D.; Alanssari, M.; Adachi, T.; Cleveland, B. T.; Dozono, M.; Ejiri, H.; Elliott, S. R.; Fujita, H.; Fujita, Y.; Fujiwara, M.; Hatanaka, K.; Holl, M.; Ishikawa, D.; Matsubara, H.; Okamura, H.; Puppe, P.; Suda, K.; Tamii, A.; Thies, J.; Yoshida, H. P.

    2016-07-01

    A high-resolution (3He,t ) charge-exchange experiment at an incident energy of 420 MeV has been performed on the double beta (β β ) decay nucleus 82Se. A detailed Gamow-Teller (GT-) strength distribution in 82Br has been extracted, which provides information to the β β -decay nuclear matrix elements. Three strong and isolated transitions, which are to the 75, 1484 and the 2087 keV states in 82Br, are found to dominate the low-excitation region below ≈2.1 MeV. Above 2.1 MeV a sudden onset of a strong GT fragmentation is observed. The degree of fragmentation resembles a situation found in the neighboring A =76 system 76Ge, whereas the observed concentration of strength in the three low-lying states is reminiscent of the heavier neighbors 96Zr and 100Mo. The strong GT transition to the 75 keV ( 1+) state makes 82Se interesting for solar neutrino detection. The 82Se(νe,e-)82Br solar neutrino capture rate in a nonoscillation scenario is therefore evaluated to 668 ±12 (stat)±60 (sys) SNU, and some of the advantages of using selenium for solar neutrino studies are discussed.

  5. Neutrino-Nucleus Reactions at MeV Region based on New Shell-Model Hamiltonians

    SciTech Connect

    Suzuki, Toshio

    2011-11-23

    Neutrino-nucleus reactions at MeV region are evaluated by using new shell model Hamiltonians, which are found to improve the description of spin degrees of freedom in nuclei as well as shell evolutions. The light element synthesis by neutrino processes in supernova explosions is discussed with the use of the new reaction cross sections for {sup 12}C and {sup 4}He. Possible constraints on the mixing angle {theta}{sub 13} and the neutrino mass hierarchy are pointed out to be imposed by the production yields of {sup 7}Li and {sup 11}B. Spin-dipole transition strengths in {sup 16}O and neutrino-induced reactions on {sup 16}O are investigated with the new improved Hamiltonian. The Gamow-Teller transition strength in {sup 56}Ni for the new Hamiltonian, which is more fragmented compared to previous calculations, is found to lead to the enhancement of the production yield of {sup 55}Mn in population III stars.

  6. Increased Tensile Strength of Carbon Nanotube Yarns and Sheets through Chemical Modification and Electron Beam Irradiation

    NASA Technical Reports Server (NTRS)

    Miller, Sandi G.; Williams, Tiffany S.; Baker, James S.; Sola, Francisco; Lebron-Colon, Marisabel; McCorkle, Linda S.; Wilmoth, Nathan G.; Gaier, James; Chen, Michelle; Meador, Michael A.

    2014-01-01

    The inherent strength of individual carbon nanotubes offers considerable opportunity for the development of advanced, lightweight composite structures. Recent work in the fabrication and application of carbon nanotube (CNT) forms such as yarns and sheets has addressed early nanocomposite limitations with respect to nanotube dispersion and loading; and has pushed the technology toward structural composite applications. However, the high tensile strength of an individual CNT has not directly translated to macro-scale CNT forms where bulk material strength is limited by inter-tube electrostatic attraction and slippage. The focus of this work was to assess post processing of CNT sheet and yarn to improve the macro-scale strength of these material forms. Both small molecule functionalization and e-beam irradiation was evaluated as a means to enhance tensile strength and Youngs modulus of the bulk CNT material. Mechanical testing results revealed a tensile strength increase in CNT sheets by 57 when functionalized, while an additional 48 increase in tensile strength was observed when functionalized sheets were irradiated; compared to unfunctionalized sheets. Similarly, small molecule functionalization increased yarn tensile strength up to 25, whereas irradiation of the functionalized yarns pushed the tensile strength to 88 beyond that of the baseline yarn.

  7. Inert strength of pristine silica glass fibers

    SciTech Connect

    Smith, W.L.; Michalske, T.A.

    1993-11-01

    Silica glass fibers have been produced and tested under ultra high vacuum (UHV) conditions to investigate the inert strength of pristine fibers in absence of reactive agents. Analysis of the coefficient of variation in diameter ({upsilon}{sub d}) vs the coefficient of variation of breaking strength ({upsilon}{sub {sigma}}) does not adequately explain the variation of breaking stress. Distribution of fiber tensile strength data suggests that the inert strength of such fibers is not single valued and that the intrinsic strength is controlled by defects in the glass. Furthermore, comparison of room temperature UHV data with LN{sub 2} data indicates that these intrinsic strengths are not temperature dependent.

  8. Wetting and strength issues at Al/alpha-alumina interfaces

    SciTech Connect

    Saiz, Eduardo; Tomsia, Antoni P.; Suganuma, Katsuaki

    2003-04-15

    The wetting behavior and strength at aluminum/alumina interfaces has been an active subject of research. Al/alumina applications include ceramic-metal composites and several applications for electronic industries. In this paper the interface strength and microstructure of Al/alpha-alumina was investigated. We discovered that in a solid-state joining, the strength of the joint increases with increasing joining temperature. In a liquid-state joining, the strength of the joint gradually decreases due to the formation of unbonded areas. The strength, sigma sub b, is expressed by the following equation as a function of unbonded area, A: sigma sub b = 2.22 A + 143 (70 percent {le} A {le} 100 percent). The highest strength reached 400 MPa when the interface was formed at around the melting temperature of aluminum. An aluminum layer close to the interface became a single crystal when it was bonded to a sapphire. The following crystallographic orientation relationship is established: (1{bar 1}1){sub Al}//(001){sub {alpha}}-Al{sub 2} O{sub 3}, (110){sub Al}//<100>{sub {alpha}}-Al{sub 2}O{sub 3}. Amorphous alumina islands were formed at the interface. In the amorphous alumina, gamma-alumina nanocrystals grew from the sapphire, with the same orientation relationship to sapphire as above.

  9. Initial Intervention Outcomes of the Dependable Strengths Project.

    ERIC Educational Resources Information Center

    McMurrer, James E., Jr.

    Dependable Strengths Articulation Process (DSAP) is a self-development process designed to facilitate positive self-constructions and improved personal functioning. This study examined the effectiveness of DSAP interventions. Participants (N=30) were college graduates who had expressed a desire to improve their educational and career planning and…

  10. Calf Strength Loss During Mechanical Unloading: Does It Matter?

    NASA Technical Reports Server (NTRS)

    English, Kirk L.; Mulavara, Ajitkumar; Bloomberg, Jacob J.; Ploutz-Snyder, Lori L.

    2016-01-01

    During the mechanical unloading of spaceflight and its ground-based analogs, muscle mass and muscle strength of the calf are difficult to preserve despite exercise countermeasures that effectively protect these parameters in the thigh. It is unclear what effects these local losses have on balance and whole body function which will be essential for successful performance of demanding tasks during future exploration missions

  11. Counseling Psychology's Commitment to Strengths: Rhetoric or Reality?

    ERIC Educational Resources Information Center

    Gerstein, Lawrence H.

    2006-01-01

    A positive psychology framework is consistent with counseling psychology's historic claim of focusing on strengths and optimal human functioning. The major articles in this issue of The Counseling Psychologist introduced many innovative, provocative, pragmatic, and useful ideas, strategies, and models related to this framework. For the most part,…

  12. Calf Strength Loss During Mechanical Unloading: Does It Matter?

    NASA Technical Reports Server (NTRS)

    English, K. L.; Mulavara, A.; Bloomberg, J.; Ploutz-Snyder, LL

    2016-01-01

    During the mechanical unloading of spaceflight and its ground-based analogs, muscle mass and muscle strength of the calf are difficult to preserve despite exercise countermeasures that effectively protect these parameters in the thigh. It is unclear what effects these local losses have on balance and whole body function which will be essential for successful performance of demanding tasks during future exploration missions.

  13. Dielectric strength of parylene HT

    SciTech Connect

    Diaham, S. Bechara, M.; Locatelli, M.-L.; Khazaka, R.; Tenailleau, C.

    2014-02-07

    The dielectric strength of parylene HT (PA-HT) films was studied at room temperature in a wide thickness range from 500 nm to 50 μm and was correlated with nano- and microstructure analyses. X-ray diffraction and polarized optical microscopy have revealed an enhancement of crystallization and spherulites development, respectively, with increasing the material thickness (d). Moreover, a critical thickness d{sub C} (between 5 and 10 μm) is identified corresponding to the beginning of spherulite developments in the films. Two distinct behaviors of the dielectric strength (F{sub B}) appear in the thickness range. For d ≥ d{sub C}, PA-HT films exhibit a decrease in the breakdown field following a negative slope (F{sub B} ∼ d{sup −0.4}), while for d < d{sub C}, it increases with increasing the thickness (F{sub B} ∼ d{sup 0.3}). An optimal thickness d{sub optim} ∼ 5 μm corresponding to a maximum dielectric strength (F{sub B} ∼ 10 MV/cm) is obtained. A model of spherulite development in PA-HT films with increasing the thickness is proposed. The decrease in F{sub B} above d{sub C} is explained by the spherulites development, whereas its increase below d{sub C} is induced by the crystallites growth. An annealing of the material shows both an enhancement of F{sub B} and an increase of the crystallites and spherulites dimensions, whatever the thickness. The breakdown field becomes thickness-independent below d{sub C} showing a strong influence of the nano-scale structural parameters. On the contrary, both nano- and micro-scale structural parameters appear as influent on F{sub B} for d ≥ d{sub C}.

  14. Strength Training and Shoulder Proprioception

    PubMed Central

    Salles, José Inácio; Velasques, Bruna; Cossich, Victor; Nicoliche, Eduardo; Ribeiro, Pedro; Amaral, Marcus Vinicius; Motta, Geraldo

    2015-01-01

    Context: Proprioception is essential to motor control and joint stability during daily and sport activities. Recent studies demonstrated that athletes have better joint position sense (JPS) when compared with controls matched for age, suggesting that physical training could have an effect on proprioception. Objective: To evaluate the result of an 8-week strength-training program on shoulder JPS and to verify whether using training intensities that are the same or divergent for the shoulder's dynamic-stabilizer muscles promote different effects on JPS. Design: Randomized controlled clinical trial. Setting: We evaluated JPS in a research laboratory and conducted training in a gymnasium. Patients or Other Participants: A total of 90 men, right handed and asymptomatic, with no history of any type of injury or shoulder instability. Intervention(s): For 8 weeks, the participants performed the strength-training program 3 sessions per week. We used 4 exercises (bench press, lat pull down, shoulder press, and seated row), with 2 sets each. Main Outcome Measure(s): We measured shoulder JPS acuity by calculating the absolute error. Results: We found an interaction between group and time. To examine the interaction, we conducted two 1-way analyses of variance comparing groups at each time. The groups did not differ at pretraining; however, a difference among groups was noted posttraining. Conclusions: Strength training using exercises at the same intensity produced an improvement in JPS compared with exercises of varying intensity, suggesting that the former resulted in improvements in the sensitivity of muscle spindles and, hence, better neuromuscular control in the shoulder. PMID:25594912

  15. Investigation of ultra violet (UV) resistance for high strength fibers

    NASA Astrophysics Data System (ADS)

    Said, M. A.; Dingwall, Brenda; Gupta, A.; Seyam, A. M.; Mock, G.; Theyson, T.

    Ultra long duration balloons (ULDB), currently under development by the National Aeronautics and Space Administration (NASA), requires the use of high strength fibers in the selected super-pressure pumpkin design. The pumpkin shape balloon concept allows clear separation of the load transferring functions of the major structural elements of the pneumatic envelope, the tendons and the film. Essentially, the film provides the gas barrier and transfers only local pressure load to the tendons. The tendons, in the mean time, provide the global pressure containing strength. In that manner, the strength requirement for the film only depends on local parameters. The tendon is made of p-phenylene-2,6-benzobisoxazole (PBO) fibers, which is selected due to its high strength to weight ratio when compared to other high performance, commercially available, fibers. High strength fibers, however, are known to degrade upon exposure to light, particularly at short wavelengths. This paper reports the results of an investigation of the resistance of four commercial high strength fibers to ultra violet (UV) exposure. The results indicate that exposing high strength fibers in continuous yarn form to UV led to serious loss in strength of the fibers except for Spectra® fibers. The adverse changes in mechanical behavior occurred over short duration of exposure compared to the 100 day duration targeted for these missions. UV blocking finishes to improve the UV resistance of these fibers are being investigated. The application of these specially formulated coatings is expected to lead to significant improvement of the UV resistance of these high performance fibers. In this publication, we report on the mechanical behavior of the fibers pre- and post-exposure to UV, but without application of the blocking finishes.

  16. High strength, tough alloy steel

    DOEpatents

    Thomas, Gareth; Rao, Bangaru V. N.

    1979-01-01

    A high strength, tough alloy steel is formed by heating the steel to a temperature in the austenite range (1000.degree.-1100.degree. C.) to form a homogeneous austenite phase and then cooling the steel to form a microstructure of uniformly dispersed dislocated martensite separated by continuous thin boundary films of stabilized retained austenite. The steel includes 0.2-0.35 weight % carbon, at least 1% and preferably 3-4.5% chromium, and at least one other substitutional alloying element, preferably manganese or nickel. The austenite film is stable to subsequent heat treatment as by tempering (below 300.degree. C.) and reforms to a stable film after austenite grain refinement.

  17. Regulation of Cell Adhesion Strength by Peripheral Focal Adhesion Distribution

    PubMed Central

    Elineni, Kranthi Kumar; Gallant, Nathan D.

    2011-01-01

    Cell adhesion to extracellular matrices is a tightly regulated process that involves the complex interplay between biochemical and mechanical events at the cell-adhesive interface. Previous work established the spatiotemporal contributions of adhesive components to adhesion strength and identified a nonlinear dependence on cell spreading. This study was designed to investigate the regulation of cell-adhesion strength by the size and position of focal adhesions (FA). The cell-adhesive interface was engineered to direct FA assembly to the periphery of the cell-spreading area to delineate the cell-adhesive area from the cell-spreading area. It was observed that redistributing the same adhesive area over a larger cell-spreading area significantly enhanced cell-adhesion strength, but only up to a threshold area. Moreover, the size of the peripheral FAs, which was interpreted as an adhesive patch, did not directly govern the adhesion strength. Interestingly, this is in contrast to the previously reported functional role of FAs in regulating cellular traction where sizes of the peripheral FAs play a critical role. These findings demonstrate, to our knowledge for the first time, that two spatial regimes in cell-spreading area exist that uniquely govern the structure-function role of FAs in regulating cell-adhesion strength. PMID:22208188

  18. Adiabatic connection at negative coupling strengths

    SciTech Connect

    Seidl, Michael; Gori-Giorgi, Paola

    2010-01-15

    The adiabatic connection of density functional theory (DFT) for electronic systems is generalized here to negative values of the coupling strength alpha (with attractive electrons). In the extreme limit alpha->-infinity a simple physical solution is presented and its implications for DFT (as well as its limitations) are discussed. For two-electron systems (a case in which the present solution can be calculated exactly), we find that an interpolation between the limit alpha->-infinity and the opposite limit of infinitely strong repulsion (alpha->+infinity) yields a rather accurate estimate of the second-order correlation energy E{sub c}{sup GL2}[rho] for several different densities rho, without using virtual orbitals. The same procedure is also applied to the Be isoelectronic series, analyzing the effects of near degeneracy.

  19. Dependence of tablet brittleness on tensile strength and porosity.

    PubMed

    Gong, Xingchu; Chang, Shao-Yu; Osei-Yeboah, Frederick; Paul, Shubhajit; Perumalla, Sathyanarayana Reddy; Shi, Limin; Sun, Wei-Jhe; Zhou, Qun; Sun, Changquan Calvin

    2015-09-30

    An analysis of data collected from 25 sets of diverse pharmaceutical powders has identified that an exponential growth function satisfactorily describes the relationship between tablet brittleness and tablet porosity while a power law function well describes the relationship between tablet brittleness and tensile strength. These equations have the potential to facilitate better characterization of tablet mechanical properties and to guide the design and optimization of pharmaceutical tablet products. PMID:26226338

  20. The strength of Miranda's lithosphere

    NASA Technical Reports Server (NTRS)

    Pappalardo, Robert; Greeley, Ronald

    1991-01-01

    In attempting to understand the endogenic processes which have shaped the surface of an icy satellite, it is desirable to quantify the failure strength of the satellite's lithosphere. In a crust that is fractured on a large scale, frictional sliding along pre-existing fractures occurs in response to lower differential stresses than required to initiate fracture of pristine rock, thus governing failure of a brittle lithosphere. Failure is predicted along favorably oriented fracture planes; if fractures of all orientations are assumed to be present in the crust (as is expected of a heavily cratered lithosphere), frictional failure relations are directly applicable. The Coulomb criterion predicts that the shear stress (sigma sub t) and normal stress (sigma sub n) components on a fracture plane at failure are related as sigma sub t = mu-sigma sub n + S sub o, where S sub o is the cohesion and mu is the coefficient of friction. At moderate to high pressures, the frictional sliding strength of most materials is found to be sigma sub t = 0.85 sigma sub n.

  1. Strength evaluation of socket joints

    NASA Technical Reports Server (NTRS)

    Rash, Larry C.

    1994-01-01

    This report documents the development of a set of equations that can be used to provide a relatively simple solution for identifying the strength of socket joints and for most cases avoid the need of more lengthy analyses. The analytical approach was verified by comparison of the contact load distributions to results obtained from a finite element analysis. The contacting surfaces for the specific joint in this analysis are in the shape of frustrums of a cone and are representative of the tapered surfaces in the socket-type joints used to join segments of model support systems for wind tunnels. The results are in the form of equations that can be used to determine the contact loads and stresses in the joint from the given geometry and externally applied loads. Equations were determined to define the bending moments and stresses along the length of the joints based on strength and materials principles. The results have also been programmed for a personal computer and a copy of the program is included.

  2. Asteroid airburst altitude vs. strength

    NASA Astrophysics Data System (ADS)

    Robertson, Darrel; Wheeler, Lorien; Mathias, Donovan

    2016-10-01

    Small NEO asteroids (<Ø140m) may not be a threat on a national or global level but can still cause a significant amount of local damage as demonstrated by the Chelyabinsk event where there was over $33 million worth of damage (1 billion roubles) and 1500 were injured, mostly due to broken glass. The ground damage from a small asteroid depends strongly on the altitude at which they "burst" where most of the energy is deposited in the atmosphere. The ability to accurately predict ground damage is useful in determining appropriate evacuation or shelter plans and emergency management.Strong asteroids, such as a monolithic boulder, fail and create peak energy deposition close to the altitude at which ram dynamic pressure exceeds the material cohesive strength. Weaker asteroids, such as a rubble pile, structurally fail at higher altitude, but it requires the increased aerodynamic pressure at lower altitude to disrupt and disperse the rubble. Consequently the resulting airbursts have a peak energy deposition at similar altitudes.In this study hydrocode simulations of the entry and break-up of small asteroids were performed to examine the effect of strength, size, composition, entry angle, and speed on the resulting airburst. This presentation will show movies of the simulations, the results of peak burst height, and the comparison to semi-analytical models.

  3. Strength of Shocked Aluminum Oxynitride

    NASA Astrophysics Data System (ADS)

    Zhu, J.; Feng, R.; Dandekar, D. P.

    2009-06-01

    Aluminum oxynitride (AlON) is a polycrystalline and transparent ceramic. An accurate characterization of its shock response is critically important for its applications as transparent armor. Shock wave profiles measured in a series of plate impact experiments on AlON [Thornhill, et al., SCCM-2005, 143-146 (2006)] have been reanalyzed using finite element wave propagation simulations and considering an effective strength behavior that is pressure- and time-dependent. The results show a stiffer shock response than that calculated previously using the jump conditions. The material has a Hugoniot elastic limit of 10.37 GPa and sustains a maximum shear stress of 4.38 GPa for shock compressions up to a shock stress of 96 GPa. The mean stress response determined from the simulations displays no sign of phase transformation and corresponds to a linear shock speed-particle velocity relation with a slope of 0.857. These results have been successfully summarized into an AlON material model consisting of compression-dependent nonlinear elasticity, pressure-dependent equilibrium strength, and over-stress relaxation. The wave profiles simulated with the model show very good agreement with the experimental measurements.

  4. Strength distribution in commercial silicon carbide materials

    NASA Technical Reports Server (NTRS)

    Dutta, Sunil

    1988-01-01

    Four-point flexural strength testing has been conducted in order to establish the baseline strength and reliability of four different commercial SiC types, in conjunction with reliable Weibull modulus values. Average strength of the samples ranged from 380 to 482 MPa at room temperature and 307 to 470 MPa at 1370 C. The strength scatter reflects the effect of flaw variability, which must be minimized to improve reliability in sintered SiC.

  5. Bonded joint strength - Static versus fatigue

    NASA Technical Reports Server (NTRS)

    Johnson, W. S.; Mall, S.

    1984-01-01

    Adhesives are commonly characterized only by their static strength even though they are used in structural joints that are subjected to fatigue loads. This paper reviews the relationship between static and fatigue strength for four different specimen types: single-lap-shear, edge-delamination, double cantilever beam, and cracked-lap-shear. It was found that the ratio of static strength to fatigue strength varied from 2.3 to 4.7, depending on the adhesive and specimen configuration.

  6. Sources of Life Strengths Appraisal Scale: A Multidimensional Approach to Assessing Older Adults' Perceived Sources of Life Strengths

    PubMed Central

    Fry, Prem S.; Debats, Dominique L.

    2014-01-01

    Both cognitive and psychosocial theories of adult development stress the fundamental role of older adults' appraisals of the diverse sources of cognitive and social-emotional strengths. This study reports the development of a new self-appraisal measure that incorporates key theoretical dimensions of internal and external sources of life strengths, as identified in the gerontological literature. Using a pilot study sample and three other independent samples to examine older adults' appraisals of their sources of life strengths which helped them in their daily functioning and to combat life challenges, adversity, and losses, a psychometric instrument having appropriate reliability and validity properties was developed. A 24-month followup of a randomly selected sample confirmed that the nine-scale appraisal measure (SLSAS) is a promising instrument for appraising older adults' sources of life strengths in dealing with stresses of daily life's functioning and also a robust measure for predicting outcomes of resilience, autonomy, and well-being for this age group. A unique strength of the appraisal instrument is its critically relevant features of brevity, simplicity of language, and ease of administration to frail older adults. Dedicated to the memory of Shanta Khurana whose assistance in the pilot work for the study was invaluable PMID:24772352

  7. Strengths and Satisfaction across the Adult Lifespan

    ERIC Educational Resources Information Center

    Isaacowitz, Derek M.; Vaillant, George E.; Seligman, Martin E. P.

    2003-01-01

    Positive psychology has recently developed a classification of human strengths (Peterson & Seligman, in press). We aimed to evaluate these strengths by investigating the strengths and life satisfaction in three adult samples recruited from the community (young adult, middle-aged, and older adult), as well as in the surviving men of the Grant study…

  8. Improving the toughness of ultrahigh strength steel

    SciTech Connect

    Soto, Koji

    2002-08-15

    The ideal structural steel combines high strength with high fracture toughness. This dissertation discusses the toughening mechanism of the Fe/Co/Ni/Cr/Mo/C steel, AerMet 100, which has the highest toughness/strength combination among all commercial ultrahigh strength steels. The possibility of improving the toughness of this steel was examined by considering several relevant factors.

  9. [Bone quality and strength relating with bone remodeling].

    PubMed

    Mori, Satoshi

    2016-01-01

    The bone has the functions of mineral reservoir and mechanical support as skeleton. Bone remodeling is the adult mode of bone metabolism, replacing old bone tissue to new one. Bone strength is determined by bone volume, structure and quality such as micro damage, degree of mineralization and collagen cross linkage, which are all controlled by bone remodeling. Bone strength decreases under high turn-over condition by decreasing bone volume and deterioration of bone structure, which also decreases under low turn-over condition by increased micro damage, increasing mineralization and AGE collagen cross linkage.

  10. Behavioral and Emotional Strengths among Youth in Systems of Care and the Effect of Race/Ethnicity

    ERIC Educational Resources Information Center

    Barksdale, Crystal L.; Azur, Melissa; Daniels, Amy M.

    2010-01-01

    Behavioral and emotional strengths are important to consider when understanding youth mental health and treatment. This study examined the association between youth strengths and functional impairment and whether this association is modified by race/ethnicity. Multinomial logistic regression models were used to estimate the effects of strengths on…

  11. Relationships between Lower Limb Muscle Strength and Locomotor Capacity in Children and Adolescents with Cerebral Palsy Who Walk Independently

    ERIC Educational Resources Information Center

    Ferland, Chantale; Lepage, Celine; Moffet, Helene; Maltais, Desiree B.

    2012-01-01

    This study aimed to quantify relationships between lower limb muscle strength and locomotor capacity for children and adolescents with cerebral palsy (CP) to identify key muscle groups for strength training. Fifty 6- to 16-year-olds with CP (Gross Motor Function Classification System level I or II) participated. Isometric muscle strength of hip…

  12. Resistance Strength Training Exercise in Children with Spinal Muscular Atrophy

    PubMed Central

    Lewelt, Aga; Krosschell, Kristin J.; Stoddard, Gregory J.; Weng, Cindy; Xue, Mei; Marcus, Robin L.; Gappmaier, Eduard; Viollet, Louis; Johnson, Barbara A.; White, Andrea T.; Viazzo-Trussell, Donata; Lopes, Philippe; Lane, Robert H.; Carey, John C.; Swoboda, Kathryn J.

    2015-01-01

    Introduction Preliminary evidence in adults with spinal muscular atrophy (SMA) and in SMA animal models suggests exercise has potential benefits in improving or stabilizing muscle strength and motor function. Methods We evaluated feasibility, safety, and effects on strength and motor function of a home-based, supervised progressive resistance strength training exercise program in children with SMA types II and III. Up to 14 bilateral proximal muscles were exercised 3 times weekly for 12 weeks. Results Nine children with SMA, aged 10.4±3.8 years, completed the resistance training exercise program. Ninety percent of visits occurred per protocol. Training sessions were pain-free (99.8%), and no study-related adverse events occurred. Trends in improved strength and motor function were observed. Conclusions A 12-week supervised, home-based, 3 days/week progressive resistance training exercise program is feasible, safe, and well tolerated in children with SMA. These findings can inform future studies of exercise in SMA. PMID:25597614

  13. Densification, microstructure and strength evolution in sintering

    NASA Astrophysics Data System (ADS)

    Xu, Xiaoping

    2000-10-01

    Powder metallurgy has the ability to fabricate high quality, complex components to close tolerances in an economical manner. In many applications, a high sintered density is desirable for an improved performance. However, sintering to a high density demands a large shrinkage, often resulting in difficulties with dimensional control. Recent studies indicate the occurrence of a sufficient densification requires a low in situ strength at high sintering temperatures. On the other hand, the low in situ strength often leads to component's distortion in response to the external forces, such as gravity. Unfortunately, lack of knowledge on strength evolution in sintering has been a major challenge to achieve an optimized combination of densification and shape retention. Therefore, the present study investigates strength evolution in sintering and the effects of processing factors. Experiments are performed on prealloyed bronze and elemental mixture of Fe-2Ni powders. For the bronze, a loose casting method is used to fabricate transverse rupture bars, while bars are injection molded for the Fe-2Ni. The in situ transverse rupture strength is measured using the Penn State Flaming Tensile Tester. Experimental results indicate a dependence of densification and strength on sintering temperature. High temperatures enhance densification and interparticle bonding, resulting in strong sintered structures. However, a low in situ strength at high test temperatures indicates the dominance of thermal softening. A strength model combining sintering theories and microstructural parameters is developed to predict both the in situ strength and the post-sintering strength. The model demonstrates the strength of the sintered materials depends on the inherent material strength, the square of neck size ratio, sintered density, and thermal softening. The model is verified by comparison of model predictions with experimental data of the bronze and Fe-2Ni. Compared to prior strength models, this

  14. Beta Decay of the Proton-Rich Nuclei 102Sn and 104Sn

    SciTech Connect

    Karny, M.; Batist, L.; Banu, A.; Becker, F.; Blazhev, A.; Brown, B. A.; Bruchle, W.; Doring, J.; Faestermann, T.; Gorska, M.; Grawe, H.; Janas, Z.; Jungclaus, A.; Kavatsyuk, M.; Kavatsyuk, O.; Kirchner, R.; La Commara, M.; Mandal, S.; Mazzocchi, C.; Miernik, K.; Mukha, I.; Muralithar, S.; Plettner, C.; Plochocki, A.; Roeckl, E.; Romoli, M.; Rykaczewski, Krzysztof Piotr; Schadel, M.; Schmidt, K.; Schwengner, R.; Zylicz, J.

    2006-01-01

    The {beta} decays of {sup 102}Sn and {sup 104}Sn were studied by using high-resolution germanium detectors as well as a Total Absorption Spectrometer (TAS). For {sup 104}Sn, with three new {beta}-delayed {gamma}-rays identified, the total Gamow-Teller strength (BGT) value of 2.7(3) was obtained. For {sup 102}Sn, the {gamma}-{gamma} coincidence data were collected for the first time, allowing us to considerably extend the decay scheme. This scheme was used to unfold the TAS data and to deduce a BGT value of 4.2(8) for this decay. This result is compared to shell model predictions, yielding a hindrance factor of 3.6(7) in agreement with those obtained previously for {sup 98}Cd and {sup 100}In. Together with the latter two, {sup 102}Sn completes the triplet of Z {le} 50, N {ge} 50 nuclei with two proton holes, one proton hole and one neutron particle, and two neutron particles with respect to the doubly magic {sup 100}Sn core.

  15. New calculations of gross β-decay properties for astrophysical applications: Speeding-up the classical r process

    NASA Astrophysics Data System (ADS)

    Möller, Peter; Pfeiffer, Bernd; Kratz, Karl-Ludwig

    2003-05-01

    Recent compilations of experimental gross β-decay properties, i.e., half-lives (T1/2) and neutron-emission probabilities (Pn), are compared to improved global macroscopic-microscopic model predictions. The model combines calculations within the quasiparticle (QP) random-phase approximation for the Gamow-Teller (GT) part with an empirical spreading of the QP strength and the gross theory for the first-forbidden part of β- decay. Nuclear masses are either taken from the 1995 data compilation of Audi et al., when available, otherwise from the finite-range droplet model. Especially for spherical and neutron-(sub-)magic isotopes a considerable improvement compared to our earlier predictions for pure GT decay (ADNDT, 1997) is observed. T1/2 and Pn values up to the neutron drip line have been used in r-process calculations within the classical “waiting-point” approximation. With the new nuclear-physics input, a considerable speeding-up of the r-matter flow is observed, in particular at those r-abundance peaks which are related to magic neutron-shell closures.

  16. β decay of the exotic Tz=-2 nuclei 48Fe,52Ni , and 56Zn

    NASA Astrophysics Data System (ADS)

    Orrigo, S. E. A.; Rubio, B.; Fujita, Y.; Gelletly, W.; Agramunt, J.; Algora, A.; Ascher, P.; Bilgier, B.; Blank, B.; Cáceres, L.; Cakirli, R. B.; Ganioǧlu, E.; Gerbaux, M.; Giovinazzo, J.; Grévy, S.; Kamalou, O.; Kozer, H. C.; Kucuk, L.; Kurtukian-Nieto, T.; Molina, F.; Popescu, L.; Rogers, A. M.; Susoy, G.; Stodel, C.; Suzuki, T.; Tamii, A.; Thomas, J. C.

    2016-04-01

    The results of a study of the β decays of three proton-rich nuclei with Tz=-2 , namely 48Fe,52Ni , and 56Zn, produced in an experiment carried out at GANIL, are reported. In all three cases we have extracted the half-lives and the total β -delayed proton emission branching ratios. We have measured the individual β -delayed protons and β -delayed γ rays and the branching ratios of the corresponding levels. Decay schemes have been determined for the three nuclei, and new energy levels are identified in the daughter nuclei. Competition between β -delayed protons and γ rays is observed in the de-excitation of the T =2 isobaric analog states in all three cases. Absolute Fermi and Gamow-Teller transition strengths have been determined. The mass excesses of the nuclei under study have been deduced. In addition, we discuss in detail the data analysis taking as a test case 56Zn, where the exotic β -delayed γ -proton decay has been observed.

  17. Spin Responses in Nuclei, Neutrino-Induced Reactions and Nucleosynthesis in Stars

    SciTech Connect

    Suzuki, Toshio

    2010-05-12

    New evaluations of neutrino-nucleus reaction rates are made for f p-shell and light p-shell nuclei as well as {sup 4}He based on new shell model Hamiltonians, which give good account of spin dependent properties such as Gamow-Teller (GT) transitions and magnetic moments in the nuclei. The reaction cross sections in light nuclei are found to be enhanced compared with those obtained by conventional Hamiltonians and previous calculations. The production yields of {sup 7}Li and {sup 11}B during supernova explosions are found to be enhanced. The GT strengths in Fe and Ni isotopes are found to be more fragmented than those by conventional Hamiltonians. In particular, this results in an enhancement of the neutrino-induced cross section on {sup 56}Ni for proton emission channel, and also an enhanced production yield of {sup 55}Mn in population III stars. Electron capture rates on Fe and Ni isotopes in astrophysical environment are studied, and they are found to be reduced systematically compared with those by conventional Hamiltonians.

  18. Structure of Light Neutron-Rich Nuclei and Important Roles of Tensor Interaction

    SciTech Connect

    Suzuki, Toshio; Otsuka, Takaharu

    2009-08-26

    Structure of light neutron-rich nuclei are investigated by shell model calculations with the use of our new shell model Hamiltonians. The new Hamiltonians take into account important roles of the tensor interaction, and can explain well the Gamow-Teller (GT) transitions in nuclei with mass 14 and 12. A new version with repulsive corrections in T = 1 monopole terms is applied to study structure of neutron-rich carbon isotopes. Characteristics of effective neutron single particle enrgies and shell evolutions toward the drip-line are discussed. Ground state energies and low lying energy levels of the isotopes are found to be well reproduced. The anomalous quenching of the magnetic dipole (M1) transition strength in {sup 17}C is also found to be well explained. GT transitions in {sup 19}C are studied. The halo nature of {sup 19}C is investigated from a retarted GT transition. Contributions from three-nucleon forces induced by {delta} excitations are shown to be the main origin of the repulsive monopole corrections in the T = 1 channel.

  19. First-forbidden β-decay rates, energy rates of β-delayed neutrons and probability of β-delayed neutron emissions for neutron-rich nickel isotopes

    NASA Astrophysics Data System (ADS)

    Nabi, Jameel-Un; Çakmak, Necla; Iftikhar, Zafar

    2016-01-01

    First-forbidden (FF) transitions can play an important role in decreasing the calculated half-lives specially in environments where allowed Gamow-Teller (GT) transitions are unfavored. Of special mention is the case of neutron-rich nuclei where, due to phase-space amplification, FF transitions are much favored. We calculate the allowed GT transitions in various pn-QRPA models for even-even neutron-rich isotopes of nickel. Here we also study the effect of deformation on the calculated GT strengths. The FF transitions for even-even neutron-rich isotopes of nickel are calculated assuming the nuclei to be spherical. Later we take into account deformation of nuclei and calculate GT + unique FF transitions, stellar β-decay rates, energy rate of β-delayed neutrons and probability of β-delayed neutron emissions. The calculated half-lives are in excellent agreement with measured ones and might contribute in speeding-up of the r-matter flow.

  20. Weak-interaction-mediated rates on iron isotopes for presupernova evolution of massive stars

    NASA Astrophysics Data System (ADS)

    Nabi, J.-Un

    2009-05-01

    During the presupernova evolution of massive stars, the isotopes of iron, 54, 55, 56Fe , are advocated to play a key role inside the cores primarily decreasing the electron-to-baryon ratio (Ye) mainly via electron capture processes thereby reducing the pressure support. Electron decay and positron capture on 55Fe , on the other hand, also have a consequential role in increasing the lepton ratio during the silicon burning phases of massive stars. The neutrinos and antineutrinos produced, as a result of these weak-interaction reactions, are transparent to the stellar matter and assist in cooling the core thereby reducing the entropy. The structure of the presupernova star is altered both by the changes in Ye and the entropy of the core material. The aim of this paper is to report the improved microscopic calculation of Gamow-Teller (GT±) strength distributions of these key isotopes of iron using the pn-QRPA theory. The main improvement comes from the incorporation of experimental deformation values for these nuclei. Additionally six different weak-interaction rates, namely electron and positron capture, electron and positron decay, and, neutrino and antineutrino cooling rates, were also calculated in presupernova matter. The calculated electron capture and neutrino cooling rates due to isotopes of iron are in good agreement with the large-scale shell model (LSSM) results. The calculated beta decay rates, however, are suppressed by three to five orders of magnitude.

  1. Conditioned Reinforcement and Response Strength

    PubMed Central

    Shahan, Timothy A

    2010-01-01

    Stimuli associated with primary reinforcers appear themselves to acquire the capacity to strengthen behavior. This paper reviews research on the strengthening effects of conditioned reinforcers within the context of contemporary quantitative choice theories and behavioral momentum theory. Based partially on the finding that variations in parameters of conditioned reinforcement appear not to affect response strength as measured by resistance to change, long-standing assertions that conditioned reinforcers do not strengthen behavior in a reinforcement-like fashion are considered. A signposts or means-to-an-end account is explored and appears to provide a plausible alternative interpretation of the effects of stimuli associated with primary reinforcers. Related suggestions that primary reinforcers also might not have their effects via a strengthening process are explored and found to be worthy of serious consideration. PMID:20885815

  2. Cobalt: for strength and color

    USGS Publications Warehouse

    Boland, Maeve A.; Kropschot, S.J.

    2011-01-01

    Cobalt is a shiny, gray, brittle metal that is best known for creating an intense blue color in glass and paints. It is frequently used in the manufacture of rechargeable batteries and to create alloys that maintain their strength at high temperatures. It is also one of the essential trace elements (or "micronutrients") that humans and many other living creatures require for good health. Cobalt is an important component in many aerospace, defense, and medical applications and is a key element in many clean energy technologies. The name cobalt comes from the German word kobold, meaning goblin. It was given this name by medieval miners who believed that troublesome goblins replaced the valuable metals in their ore with a substance that emitted poisonous fumes when smelted. The Swedish chemist Georg Brandt isolated metallic cobalt-the first new metal to be discovered since ancient times-in about 1735 and identified some of its valuable properties.

  3. Conditioned reinforcement and response strength.

    PubMed

    Shahan, Timothy A

    2010-03-01

    Stimuli associated with primary reinforcers appear themselves to acquire the capacity to strengthen behavior. This paper reviews research on the strengthening effects of conditioned reinforcers within the context of contemporary quantitative choice theories and behavioral momentum theory. Based partially on the finding that variations in parameters of conditioned reinforcement appear not to affect response strength as measured by resistance to change, long-standing assertions that conditioned reinforcers do not strengthen behavior in a reinforcement-like fashion are considered. A signposts or means-to-an-end account is explored and appears to provide a plausible alternative interpretation of the effects of stimuli associated with primary reinforcers. Related suggestions that primary reinforcers also might not have their effects via a strengthening process are explored and found to be worthy of serious consideration.

  4. An indentation fatigue strength law

    NASA Astrophysics Data System (ADS)

    Xu, Baoxing; Yonezu, Akio; Chen, Xi

    2010-05-01

    Indentation fatigue, where a cyclic load is applied on the sample via an indenter, emerges as an alternative approach for measuring the fatigue properties of materials. We have carried out indentation fatigue tests on a poly(vinyl chloride) (PVC) bulk material, as well as on TiN and NiP films/coatings deposited on SUS304 steel substrates, and demonstrate that a simple power-law relationship can be established between the indentation load amplitude and number of cycles to failure. Such a law is very similar to the conventional fatigue strength law obtained from uniaxial tests. The agreement between the fatigue stress exponents obtained by uniaxial and indentation fatigue tests suggests the potential applicability of the indentation fatigue technique for extracting the fatigue properties of materials.

  5. Conditioned reinforcement and response strength.

    PubMed

    Shahan, Timothy A

    2010-03-01

    Stimuli associated with primary reinforcers appear themselves to acquire the capacity to strengthen behavior. This paper reviews research on the strengthening effects of conditioned reinforcers within the context of contemporary quantitative choice theories and behavioral momentum theory. Based partially on the finding that variations in parameters of conditioned reinforcement appear not to affect response strength as measured by resistance to change, long-standing assertions that conditioned reinforcers do not strengthen behavior in a reinforcement-like fashion are considered. A signposts or means-to-an-end account is explored and appears to provide a plausible alternative interpretation of the effects of stimuli associated with primary reinforcers. Related suggestions that primary reinforcers also might not have their effects via a strengthening process are explored and found to be worthy of serious consideration. PMID:20885815

  6. Technique for Predicting the RF Field Strength Inside an Enclosure

    NASA Technical Reports Server (NTRS)

    Hallett, M.; Reddell, J.

    1998-01-01

    This Memorandum presents a simple analytical technique for predicting the RF electric field strength inside an enclosed volume in which radio frequency radiation occurs. The technique was developed to predict the radio frequency (RF) field strength within a launch vehicle's fairing from payloads launched with their telemetry transmitters radiating and to the impact of the radiation on the vehicle and payload. The RF field strength is shown to be a function of the surface materials and surface areas. The method accounts for RF energy losses within exposed surfaces, through RF windows, and within multiple layers of dielectric materials which may cover the surfaces. This Memorandum includes the rigorous derivation of all equations and presents examples and data to support the validity of the technique.

  7. Vitamin D status is associated with grip strength in centenarians.

    PubMed

    Haslam, Alyson; Johnson, Mary Ann; Hausman, Dorothy B; Cress, M Elaine; Houston, Denise K; Davey, Adam; Poon, Leonard W

    2014-01-01

    Low serum concentrations of 25-hydroxyvitamin D (25(OH)D) have been associated with poor physical function in older adults, but few, if any, studies have examined this relationship in the very old. Therefore, the purpose of this study is to examine this relationship in the very old. Serum 25(OH)D concentrations were obtained from 194 centenarians and near centenarians (98 years and older). The associations between 25(OH)D concentrations and measures of physical function were evaluated with unadjusted and adjusted regression models. We found that 35% of centenarians had 25(OH)D concentrations less than 50 nmol/L. Adjusted mean grip strength was lower for centenarians with 25(OH)D concentrations less than 75 nmol/L than for centenarians with higher concentrations (P<0.05). However, there were no differences in the Georgia Centenarian Study (GCS) Composite Scale, a global measure of physical function, between those with higher and lower 25(OH)D concentrations. We conclude that low 25(OH)D concentrations are associated with poor grip strength, but not GCS Composite Scale, in the very old. Considering the high burden of poor physical function in older adults, understanding the relationship between vitamin D and different measures of physical function, including strength, becomes increasingly important.

  8. The Distribution of Subjective Memory Strength: List Strength and Response Bias

    ERIC Educational Resources Information Center

    Criss, Amy H.

    2009-01-01

    Models of recognition memory assume that memory decisions are based partially on the subjective strength of the test item. Models agree that the subjective strength of targets increases with additional time for encoding however the origin of the subjective strength of foils remains disputed. Under the fixed strength assumption the distribution of…

  9. Charge exchange reactions and solar neutrino detection in 81Br

    NASA Astrophysics Data System (ADS)

    Liu, K. F.; Gabbard, F.

    1983-01-01

    The feasibility of 81Br as the detector of the solar neutrino flux hinges upon the knowledge of the Gamow-Teller matrix element from the ground state of 81Br to the 52- state at 0.457 MeV in 81Kr. The possibility of obtaining this matrix element is discussed in terms of the (p, n) and (3He, t) charge exchange reactions. NUCLEAR REACTIONS 81Br(p, n)81Kr and 81Br(3He, t)81Kr Gamow-Teller transitions; solar neutrino detection.

  10. Collagen orientation and leather strength for selected mammals.

    PubMed

    Sizeland, Katie H; Basil-Jones, Melissa M; Edmonds, Richard L; Cooper, Sue M; Kirby, Nigel; Hawley, Adrian; Haverkamp, Richard G

    2013-01-30

    Collagen is the main structural component of leather, skin, and some other applications such as medical scaffolds. All of these materials have a mechanical function, so the manner in which collagen provides them with their strength is of fundamental importance and was investigated here. This study shows that the tear strength of leather across seven species of mammals depends on the degree to which collagen fibrils are aligned in the plane of the tissue. Tear-resistant material has the fibrils contained within parallel planes with little crossover between the top and bottom surfaces. The fibril orientation is observed using small-angle X-ray scattering in leather, produced from skin, with tear strengths (normalized for thickness) of 20-110 N/mm. The orientation index, 0.420-0.633, is linearly related to tear strength such that greater alignment within the plane of the tissue results in stronger material. The statistical confidence and diversity of animals suggest that this is a fundamental determinant of strength in tissue. This insight is valuable in understanding the performance of leather and skin in biological and industrial applications.

  11. Tensile bond strength between custom tray and elastomeric impression material.

    PubMed

    Maruo, Yukinori; Nishigawa, Goro; Oka, Morihiko; Minagi, Shogo; Irie, Masao; Suzuki, Kazuomi

    2007-05-01

    The aim of this study was to investigate how to achieve sufficient and stable adhesive strength between impression material and tray. Impression materials were molded between autopolymerizing resin columns, and tensile strength was measured as a function of these factors: tray storage time (1, 2, 4, 7, and 10 days), adhesive drying time (0, 1, 5, 10, and 15 minutes), and tray surface roughness (air abrasion, bur-produced roughness, and no treatment). Tensile bond strength was not affected by tray storage time throughout the entire evaluation period of 10 days. As for tray adhesive drying time, Reprosil and Exaimplant yielded extremely low values for drying times of 10 minutes or less (P<0.05), while Imprint II and Impregum were not influenced by drying time. Vinyl polysiloxane achieved the highest adhesive strength with bur-produced roughness, which was significantly higher than with air abrasion or no treatment (P<0.05), whereas polyether achieved the lowest value with bur-produced roughness (P<0.05). It was concluded that surface treatment of custom tray should be adapted to the type of impression material used to achieve optimum bond strength.

  12. Anomalous scaling law of strength and toughness of cellulose nanopaper

    PubMed Central

    Zhu, Hongli; Zhu, Shuze; Jia, Zheng; Parvinian, Sepideh; Li, Yuanyuan; Vaaland, Oeyvind; Hu, Liangbing; Li, Teng

    2015-01-01

    The quest for both strength and toughness is perpetual in advanced material design; unfortunately, these two mechanical properties are generally mutually exclusive. So far there exists only limited success of attaining both strength and toughness, which often needs material-specific, complicated, or expensive synthesis processes and thus can hardly be applicable to other materials. A general mechanism to address the conflict between strength and toughness still remains elusive. Here we report a first-of-its-kind study of the dependence of strength and toughness of cellulose nanopaper on the size of the constituent cellulose fibers. Surprisingly, we find that both the strength and toughness of cellulose nanopaper increase simultaneously (40 and 130 times, respectively) as the size of the constituent cellulose fibers decreases (from a mean diameter of 27 μm to 11 nm), revealing an anomalous but highly desirable scaling law of the mechanical properties of cellulose nanopaper: the smaller, the stronger and the tougher. Further fundamental mechanistic studies reveal that reduced intrinsic defect size and facile (re)formation of strong hydrogen bonding among cellulose molecular chains is the underlying key to this new scaling law of mechanical properties. These mechanistic findings are generally applicable to other material building blocks, and therefore open up abundant opportunities to use the fundamental bottom-up strategy to design a new class of functional materials that are both strong and tough. PMID:26150482

  13. The effect of Kinesio Taping on handgrip strength.

    PubMed

    Lemos, Thiago Vilela; Pereira, Kelice Cristina; Protássio, Carina Celedonio; Lucas, Lorrane Barbosa; Matheus, Joao Paulo C

    2015-03-01

    [Purpose] The purpose of this research was to evaluate the change in muscle function induced by a Kinesio Tape application with no or moderate tension, to the dominant and non-dominant arms. [Subjects and Methods] This research was a quantitative study, in which 75 women participated. The subjects, aged 18-30 years, were divided into 3 groups, Kinesio, Kinesio without Tension, and Control, and they were assessed before the taping intervention and after 30 minutes, 24 hours, and 48 hours of taping. [Results] The Kinesio group subjects demonstrated an increase in handgrip strength after 30 minutes, 24 hours, and 48 hours of tape application compared to control. A statistically significant increase in strength was observed in the Kinesio group comparison to the Control after 24 hours and 48 hours for the right hand, and after 48 hours for the left hand. Improvement in the Kinesio group compared to the Kinesio without Tension was observed only after 24 hours of taping application, and only in the right hand. [Conclusion] The Kinesio Taping method augmented the handgrip strength of healthy women, and the increase in grip strength was maintained for 48 hours after its application; the dominant hand demonstrated the greatest strength values.

  14. The effect of Kinesio Taping on handgrip strength

    PubMed Central

    Lemos, Thiago Vilela; Pereira, Kelice Cristina; Protássio, Carina Celedonio; Lucas, Lorrane Barbosa; Matheus, Joao Paulo C.

    2015-01-01

    [Purpose] The purpose of this research was to evaluate the change in muscle function induced by a Kinesio Tape application with no or moderate tension, to the dominant and non-dominant arms. [Subjects and Methods] This research was a quantitative study, in which 75 women participated. The subjects, aged 18–30 years, were divided into 3 groups, Kinesio, Kinesio without Tension, and Control, and they were assessed before the taping intervention and after 30 minutes, 24 hours, and 48 hours of taping. [Results] The Kinesio group subjects demonstrated an increase in handgrip strength after 30 minutes, 24 hours, and 48 hours of tape application compared to control. A statistically significant increase in strength was observed in the Kinesio group comparison to the Control after 24 hours and 48 hours for the right hand, and after 48 hours for the left hand. Improvement in the Kinesio group compared to the Kinesio without Tension was observed only after 24 hours of taping application, and only in the right hand. [Conclusion] The Kinesio Taping method augmented the handgrip strength of healthy women, and the increase in grip strength was maintained for 48 hours after its application; the dominant hand demonstrated the greatest strength values. PMID:25931682

  15. Testing resonating vector strength: Auditory system, electric fish, and noise

    NASA Astrophysics Data System (ADS)

    Leo van Hemmen, J.; Longtin, André; Vollmayr, Andreas N.

    2011-12-01

    Quite often a response to some input with a specific frequency ν○ can be described through a sequence of discrete events. Here, we study the synchrony vector, whose length stands for the vector strength, and in doing so focus on neuronal response in terms of spike times. The latter are supposed to be given by experiment. Instead of singling out the stimulus frequency ν○ we study the synchrony vector as a function of the real frequency variable ν. Its length turns out to be a resonating vector strength in that it shows clear maxima in the neighborhood of ν○ and multiples thereof, hence, allowing an easy way of determining response frequencies. We study this "resonating" vector strength for two concrete but rather different cases, viz., a specific midbrain neuron in the auditory system of cat and a primary detector neuron belonging to the electric sense of the wave-type electric fish Apteronotus leptorhynchus. We show that the resonating vector strength always performs a clear resonance correlated with the phase locking that it quantifies. We analyze the influence of noise and demonstrate how well the resonance associated with maximal vector strength indicates the dominant stimulus frequency. Furthermore, we exhibit how one can obtain a specific phase associated with, for instance, a delay in auditory analysis.

  16. STRENGTH OF A C-SPHERE FLEXURE SPECIMEN

    SciTech Connect

    Wereszczak, Andrew A; Wang, Wei; Jadaan, Osama M.; Lance, Michael J; Lin, Hua-Tay

    2007-01-01

    A 'C-Sphere' flexure strength specimen geometry was conceived and developed to measure a relevant strength of bearing-grade Si{sub 3}N{sub 4} balls and to relate that to surface-located strength-limiting flaws and to ultimately link those flaw populations to rolling contact fatigue performance. A slot was machined into the balls to a set depth to produce the C-sphere geometry. C-sphere specimens were then diametrally compressed to produce a monotonically increasing flexure or hoop tensile stress at their surface that caused their fracture. The strength was determined using the combination of failure load, C-sphere geometry, and FEA, and the stress field was used to determine C-sphere effective areas and effective volumes as a function of Weibull modulus. A description of the specimen and the aforementioned analysis are provided and a comparison of C-sphere flexure strength distributions of two bearing grade Si{sub 3}N{sub 4} materials (NBD200 and SN101C) is given.

  17. Bending strength model for internal spur gear teeth

    NASA Technical Reports Server (NTRS)

    Savage, Michael; Rubadeux, K. L.; Coe, H. H.

    1995-01-01

    Internal spur gear teeth are normally stronger than pinion teeth of the same pitch and face width since external teeth are smaller at the base. However, ring gears which are narrower have an unequal addendum or are made of a material with a lower strength than that of the meshing pinion may be loaded more critically in bending. In this study, a model for the bending strength of an internal gear tooth as a function of the applied load pressure angle is presented which is based on the inscribed Lewis constant strength parabolic beam. The bending model includes a stress concentration factor and an axial compression term which are extensions of the model for an external gear tooth. The geometry of the Lewis factor determination is presented, the iteration to determine the factor is described, and the bending strength J factor is compared to that of an external gear tooth. This strength model will assist optimal design efforts for unequal addendum gears and gears of mixed materials.

  18. Strength Matters: Resisting Erosion Across Upland Landscapes

    NASA Astrophysics Data System (ADS)

    Heimsath, A. M.

    2012-12-01

    Soil-covered upland landscapes comprise a critical part of the habitable world and our understanding of their evolution as a function of different climatic, tectonic, and geologic regimes is important across a wide range of disciplines. Erosion laws, which help direct our study and drive our models of Earth surface processes are based on little field data. Soil production and transport play essential roles in controlling the spatial variation of soil depth and therefore hillslope hydrological processes, vegetation, and soil biological activity. Field-based confirmation of the hypothesized relationship between soil thickness and soil production is recent, however, and here we quantify the first direct physical explanation of variable soil production across landscapes. We report clear empirical linkages between the mechanical strength of the parent material (erodability), soil production rates determined from the same material, and the routing of water on hillslopes. Specifically, soil production rates determined from in situ produced 10Be and 26Al decrease exponentially with increasing shear strength of parent material across three very different field sites, all underlain by granitic bedrock: The Point Reyes Peninsular and The San Gabriel Mountains in California and the Nunnock River, Australia field site used for extensive previous work. At the same field sites, we use fallout radionuclide profiles to show how the flux of water across the soil-saprolite boundary changes significantly along the hillslope profile. Specifically, we quantify the transition from creep dominated bioturbation on the upper parts of the hillslopes to overland flow dominated surficial erosion towards the axis of the unchannelled swales. Our field-based data, collected across a full range of erosion and soil production rates and topographic settings, help explain more clearly the linkages between biota, weathering, hillslope hydrology, and the evolution of the Earth's surface.

  19. Simulation studies for surfaces and materials strength

    NASA Technical Reports Server (NTRS)

    Halicioglu, Timur; Smith, Grant D.

    1994-01-01

    Computer simulation studies were conducted to investigate materials properties. All the calculations were carried out using atomic level simulation techniques which are based on semiempirical or model functions. During this project, functions with varying degrees of complexity were derived and employed in simulations. Investigations include covalently bonded materials as well as systems involving metal atoms. For small clusters calculated results provided information on various energy- and structure-related properties along with vibrational characteristics. Also, energy barriers for configurational transitions were calculated for selected cases. Simulation calculations for surfaces produced new results in areas related to surface energies, reconstructions and relaxations, surface defects, surface stresses as well as adsorption and nucleation processes. Simulations were also performed on bulk materials. Calculated results provided an atomic level understanding on energetics and structures of point defects, crystal stability, elastic properties, and materials strength for various systems. Calculations involving polymeric materials include studies of polar polymer melts and polymer/solid interfaces. Simulations employing specially developed codes provided significant information about energetics and conformational characteristics of different polymeric chains.

  20. Cognitive Abilities and Left-Handedness: An Interaction between Familial Sinistrality and Strength of Handedness.

    ERIC Educational Resources Information Center

    Searleman,Alan; And Others

    1984-01-01

    The Scholastic Aptitude Test scores of 86 left-handed undergraduates were examined as a function of familial sinistrality, strength of left-handedness, and sex. An interaction was found between familial sinistrality and strength of handedness in terms of aptitude. (Author/BS)

  1. Strength and Endurance Training Prescription in Healthy and Frail Elderly

    PubMed Central

    Cadore, Eduardo Lusa; Pinto, Ronei Silveira; Bottaro, Martim; Izquierdo, Mikel

    2014-01-01

    Aging is associated with declines in the neuromuscular and cardiovascular systems, resulting in an impaired capacity to perform daily activities. Frailty is an age-associated biological syndrome characterized by decreases in the biological functional reserve and resistance to stressors due to changes in several physiological systems, which puts older individuals at special risk of disability. To counteract the neuromuscular and cardiovascular declines associated with aging, as well as to prevent and treat the frailty syndrome, the strength and endurance training seems to be an effective strategy to improve muscle hypertrophy, strength and power output, as well as endurance performance. The first purpose of this review was discuss the neuromuscular adaptations to strength training, as well as the cardiovascular adaptations to endurance training in healthy and frail elderly subjects. In addition, the second purpose of this study was investigate the concurrent training adaptations in the elderly. Based on the results found, the combination of strength and endurance training (i.e., concurrent training) performed at moderate volume and moderate to high intensity in elderly populations is the most effective way to improve both neuromuscular and cardiorespiratory functions. Moreover, exercise interventions that include muscle power training should be prescribed to frail elderly in order to improve the overall physical status of this population and prevent disability. PMID:24900941

  2. The in situ transverse lamina strength of composite laminates

    NASA Technical Reports Server (NTRS)

    Flaggs, D. L.

    1983-01-01

    The objective of the work reported in this presentation is to determine the in situ transverse strength of a lamina within a composite laminate. From a fracture mechanics standpoint, in situ strength may be viewed as constrained cracking that has been shown to be a function of both lamina thickness and the stiffness of adjacent plies that serve to constrain the cracking process. From an engineering point of view, however, constrained cracking can be perceived as an apparent increase in lamina strength. With the growing need to design more highly loaded composite structures, the concept of in situ strength may prove to be a viable means of increasing the design allowables of current and future composite material systems. A simplified one dimensional analytical model is presented that is used to predict the strain at onset of transverse cracking. While it is accurate only for the most constrained cases, the model is important in that the predicted failure strain is seen to be a function of a lamina's thickness d and of the extensional stiffness bE theta of the adjacent laminae that constrain crack propagation in the 90 deg laminae.

  3. Dynamic Strength Ceramic Nanocomposites Under Pulse Loading

    NASA Astrophysics Data System (ADS)

    Skripnyak, Evgeniya G.; Skripnyak, Vladimir V.; Vaganova, Irina K.; Skripnyak, Vladimir A.

    2015-06-01

    Multi-scale computer simulation approach has been applied to research of strength of nanocomposites under dynamic loading. The influence of mesoscopic substructures on the dynamic strength of ceramic and hybrid nanocomposites, which can be formed using additive manufacturing were numerically investigated. At weak shock wave loadings the shear strength and the spall strength of ceramic and hybrid nanocomposites depends not only phase concentration and porosity, but size parameters of skeleton substructures. The influence of skeleton parameter on the shear strength and the spall strength of ceramic nanocomposites with the same concentration of phases decreases with increasing amplitude of the shock pulse of microsecond duration above the double amplitude of the Hugoniot elastic limit of nanocomposites. This research carried out in 2014 -2015 was supported by grant from The Tomsk State University Academic D.I. Mendeleev Fund Program and also Ministry of Sciences and Education of Russian Federation (State task 2014/223, project 1943, Agreement 14.132.

  4. Fracture toughness and strength of 96% alumina

    SciTech Connect

    Price, D.B.; Chinn, R.E.; McNerney, K.R.; Brog, T.K.; Kim, C.Y.; Krutyholowa, M.W.; Chen, N.W.; Haun, M.J.

    1997-05-01

    There exists a need to understand the controlling factors that simultaneously impact strength and toughness in 96% alumina. The enhancement of both strength and toughness enables designers to extend the use limits and reliability for structural ceramics. This article presents mechanical property results from a group study examining the use of different alkaline-earth aluminosilicate intergranular compositions containing magnesium, calcium and strontium oxides (RO) in 96% alumina. Principal results address trends in indentation strength toughness and modulus of rupture. Trends in the data are presented relative to existing theories of thermal expansion mismatch toughening, grain-bridging crack-wake effect and crack deflection mechanisms. Strength is addressed in terms of strength after indentation, crack growth of indentation flaws and Weibull characterization for the strength distribution.

  5. The ideal strength and mechanical hardness of solids

    SciTech Connect

    Krenn, Christopher

    2000-04-01

    Relationships between intrinsic mechanical hardness and atomic-scale properties are reviewed, Hardness scales closely and linearly with shear modulus for a given class of material (covalent, ionic or metallic). A two-parameter fit and a Peierls-stress model produce a more universal scaling relationship, but no model can explain differences in hardness between the transition metal carbides and nitrides. Calculations of ''ideal strength'' (defined by the limit of elastic stability of a perfect crystal) are proposed. The ideal shear strengths of fcc aluminum and copper are calculated using ab initio techniques and allowing for structural relaxation of all five strain components other than the imposed strain. The strengths of Al and Cu are similar (8-9% of the shear modulus), but the geometry of the relaxations in Al and Cu is very different. The relaxations are consistent with experimentally measured third-order elastic constants. The general thermodynamic conditions of elastic stability that set the upper limits of mechanical strength are derived. The conditions of stability are shown for cubic (hydrostatic), tetragonal (tensile) and monoclinic (shear) distortions of a cubic crystal. The implications of this stability analysis to first-principles calculations of ideal strength are discussed, and a method to detect instabilities orthogonal to the direction of the applied stress is identified. The relaxed ideal shear and tensile strengths of bcc tungsten are also calculated using ab initio techniques and are favorably compared to recent nano-indentation measurements. The {l_brace}100{r_brace} tensile strength (29.5 GPa) is governed by the Bain instability. The shear strengths in the weak directions on {l_brace}110{r_brace}, {l_brace}112{r_brace}, and {l_brace}123{r_brace} planes are very nearly equal ({approx} 18 GPa) and occur at approximately the same strain (17-18%). This isotropy is a function of the linear elastic isotropy for shear in directions containing {l

  6. Fracture strength of silicon solar cells

    NASA Technical Reports Server (NTRS)

    Chen, C. P.

    1979-01-01

    A test program was developed to determine the nature and source of the flaw controlling the fracture of silicon solar cells and to provide information regarding the mechanical strength of cells. Significant changes in fracture strengths were found in seven selected in-process wafer-to-cell products from a manufacturer's production line. The fracture strength data were statistically analyzed and interpreted in light of the exterior flaw distribution of the samples.

  7. Strength in numbers? Not always!

    NASA Astrophysics Data System (ADS)

    Schinazi, Rinaldo B.

    2011-05-01

    We propose a simple model to compute the probability of success under a particular quorum sensing strategy. We show that this quorum sensing strategy has a higher probability of success than an individualistic strategy when, for instance, the probability of success for a single individual is low and the cost of building a quorum is not too high. On the other hand, if the cost of building a quorum is too high, then the probability of success under quorum sensing always decreases as a function of the quorum. We also give an example showing that the probability of success as a function of the quorum is not necessarily monotone.

  8. Mechanical strength and stability of lithium aluminate

    NASA Astrophysics Data System (ADS)

    Brimhall, J. L.

    1992-06-01

    Pacific Northwest Laboratory (PNL) investigated the strength and resistance to thermal shock of lithium aluminate annular pellets. The room temperature, axial compressive fracture strength of pellets made at Westinghouse Advanced Energy Systems (WAES) varied from 80 to 133 ksi. The strength at 430 C (806 F) was to 30 to 40 percent lower. The strength at 900 C (1652 F) showed a wide variation with one measurement near 90 ksi. These strength values are consistent with other data and predictions made in the literature when the grain size and porosity of the microstructure are taken into account. In diametral compression tests, the fracture strengths were much lower due to the existence of tensile stresses in some pellet regions from this type of loading. However, the fracture stresses were still generally higher than those reported in the literature; this fracture resistance probably reflects the better quality of the pellets tested in this study. Measurements on pellets made at PNL indicated lower strengths compared to the WAES material. This strength difference could be accounted for by different processing technologies: material made at PNL was cold-pressed and sintered with high porosity whereas the WAES material was isostatically hot-pressed with high density. Thermal shocking of the material by ramping to 900 C in two minutes did not have an observable effect on the microstructure or the strength of any of the pellets.

  9. Accelerated Strength Testing of Thermoplastic Composites

    NASA Technical Reports Server (NTRS)

    Reeder, J. R.; Allen, D. H.; Bradley, W. L.

    1998-01-01

    Constant ramp strength tests on unidirectional thermoplastic composite specimens oriented in the 90 deg. direction were conducted at constant temperatures ranging from 149 C to 232 C. Ramp rates spanning 5 orders of magnitude were tested so that failures occurred in the range from 0.5 sec. to 24 hrs. (0.5 to 100,000 MPa/sec). Below 204 C, time-temperature superposition held allowing strength at longer times to be estimated from strength tests at shorter times but higher temperatures. The data indicated that a 50% drop in strength might be expected for this material when the test time is increased by 9 orders of magnitude. The shift factors derived from compliance data applied well to the strength results. To explain the link between compliance and strength, a viscoelastic fracture model was investigated. The model, which used compliance as input, was found to fit the strength data only if the critical fracture energy was allowed to vary with temperature reduced stress rate. This variation in the critical parameter severely limits its use in developing a robust time-dependent strength model. The significance of this research is therefore seen as providing both the indication that a more versatile acceleration method for strength can be developed and the evidence that such a method is needed.

  10. Pitch strength of normal and dysphonic voices

    PubMed Central

    Shrivastav, Rahul; Eddins, David A.; Anand, Supraja

    2012-01-01

    Two sounds with the same pitch may vary from each other based on saliency of their pitch sensation. This perceptual attribute is called “pitch strength.” The study of voice pitch strength may be important in quantifying of normal and pathological qualities. The present study investigated how pitch strength varies across normal and dysphonic voices. A set of voices (vowel /a/) selected from the Kay Elemetrics Disordered Voice Database served as the stimuli. These stimuli demonstrated a wide range of voice quality. Ten listeners judged the pitch strength of these stimuli in an anchored magnitude estimation task. On a given trial, listeners heard three different stimuli. The first stimulus represented very low pitch strength (wide-band noise), the second stimulus consisted of the target voice and the third stimulus represented very high pitch strength (pure tone). Listeners estimated pitch strength of the target voice by positioning a continuous slider labeled with values between 0 and 1, reflecting the two anchor stimuli. Results revealed that listeners can judge pitch strength reliably in dysphonic voices. Moderate to high correlations with perceptual judgments of voice quality suggest that pitch strength may contribute to voice quality judgments. PMID:22423721

  11. Muscular strength after total hip arthroplasty

    PubMed Central

    Winther, Siri B; Husby, Vigdis S; Foss, Olav A; Wik, Tina S; Svenningsen, Svein; Engdal, Monika; Haugan, Kristin; Husby, Otto S

    2016-01-01

    Background and purpose Minimizing the decrease in muscular strength after total hip arthroplasty (THA) might allow patients to recover faster. We evaluated muscular strength in patients who were operated on using 3 surgical approaches. Patients and methods In a prospective cohort study, 60 patients scheduled for primary THA were allocated to the direct lateral, posterior, or anterior approach. Leg press and abduction strength were evaluated 2 weeks or less preoperatively, 2 and 8 days postoperatively, and at 6-week and 3-month follow-up. Results Differences in maximal strength change were greatest after 2 and 8 days. The posterior and anterior approaches produced less decrease in muscular strength than the direct lateral approach. 6 weeks postoperatively, the posterior approach produced greater increase in muscular strength than the direct lateral approach, and resulted in a greater increase in abduction strength than the anterior approach. At 3-month follow-up, no statistically significant differences between the groups were found. The operated legs were 18% weaker in leg press and 15% weaker in abduction than the unoperated legs, and the results were similar between groups. Interpretation The posterior and anterior approaches appeared to have the least negative effect on abduction and leg press muscular strength in the first postoperative week; the posterior approach had the least negative effect, even up to 6 weeks postoperatively. THA patients have reduced muscle strength in the operated leg (compared to the unoperated leg) 3 months after surgery. PMID:26141371

  12. Quadriceps strength and weight acceptance strategies continue to improve two years after anterior cruciate ligament reconstruction.

    PubMed

    Roewer, Ben D; Di Stasi, Stephanie L; Snyder-Mackler, Lynn

    2011-07-01

    The anterior cruciate ligament (ACL) is the most commonly-injured knee ligament during sporting activities. After injury, most individuals experience episodes of the knee giving way during daily activities (non-copers). Non-copers demonstrate asymmetrical quadriceps strength and movement patterns, which could have long-term deleterious effects on the integrity of the knee joint. The purpose of this study was to determine if non-copers resolve their strength and movement asymmetries within two years after surgery. 26 Non-copers were recruited to undergo pre-operative quadriceps strength testing and 3-dimensional gait analysis. Subjects underwent surgery to reconstruct the ligament followed by physical therapy focused on restoring normal range of motion, quadriceps strength, and function. Subjects returned for quadriceps strength testing and gait analysis six months and two years after surgery. Acutely after injury, quadriceps strength was asymmetric between limbs, but resolved six months after surgery. Asymmetric knee angles, knee moments, and knee and hip power profiles were also observed acutely after injury and persisted six months after surgery despite subjects achieving symmetrical quadriceps strength. Two years after surgery, quadriceps strength in the involved limb continued to improve and most kinematic and kinetic asymmetries resolved. These findings suggest that adequate quadriceps strength does not immediately resolve gait asymmetries in non-copers. They also suggest that non-copers have the capacity to improve their quadriceps strength and gait symmetry long after ACL reconstruction.

  13. Lung models: strengths and limitations.

    PubMed

    Martonen, T B; Musante, C J; Segal, R A; Schroeter, J D; Hwang, D; Dolovich, M A; Burton, R; Spencer, R M; Fleming, J S

    2000-06-01

    The most widely used particle dosimetry models are those proposed by the National Council on Radiation Protection, International Commission for Radiological Protection, and the Netherlands National Institute of Public Health and the Environment (the RIVM model). Those models have inherent problems that may be regarded as serious drawbacks: for example, they are not physiologically realistic. They ignore the presence and commensurate effects of naturally occurring structural elements of lungs (eg, cartilaginous rings, carinal ridges), which have been demonstrated to affect the motion of inhaled air. Most importantly, the surface structures have been shown to influence the trajectories of inhaled particles transported by air streams. Thus, the model presented herein by Martonen et al may be perhaps the most appropriate for human lung dosimetry. In its present form, the model's major "strengths" are that it could be used for diverse purposes in medical research and practice, including: to target the delivery of drugs for diseases of the respiratory tract (eg, cystic fibrosis, asthma, bronchogenic carcinoma); to selectively deposit drugs for systemic distribution (eg, insulin); to design clinical studies; to interpret scintigraphy data from human subject exposures; to determine laboratory conditions for animal testing (ie, extrapolation modeling); and to aid in aerosolized drug delivery to children (pediatric medicine). Based on our research, we have found very good agreement between the predictions of our model and the experimental data of Heyder et al, and therefore advocate its use in the clinical arena. In closing, we would note that for the simulations reported herein the data entered into our computer program were the actual conditions of the Heyder et al experiments. However, the deposition model is more versatile and can simulate many aerosol therapy scenarios. For example, the core model has many computer subroutines that can be enlisted to simulate the

  14. A hypothesis-assessment model of categorical argument strength.

    PubMed

    McDonald, J; Samuels, M; Rispoli, J

    1996-05-01

    According to the proposed hypothesis-assessment model, the strength of inductive categorical arguments, such as {All Robins Have Substance X therefore All Birds Have Substance X}, is determined by the same factors that affect hypothesis plausibility in the everyday social milieu. The premises of such arguments are viewed as evidence and the conclusion is viewed as a hypothesis. Specifically, the proposed model predicts that the perceived strength of general-conclusion categorical arguments will be a function of (a) the number of premises that instantiate the conclusion; (b) the scope of the conclusion; and (c) the number of accessed alternatives to the conclusion. In Experiment 1, one group rated the strength of individual arguments and another constructed superordinate hypotheses in response to the premise information alone. Most of the variance in perceived argument strength was accounted for by the proposed predictors, R = .94. Experiment 2 employed a new set of arguments and included an additional forced-choice condition in which subjects had to choose the stronger of two arguments. Again, the correlation between predictors and argument strength was high, R = .91, and, all significant forced-choice preferences except one were correctly predicted by the model. The one unpredicted preference suggests the need to include conclusion accessibility as a fourth factor. Also, on a subset of the forced-choice pairs in which no significant preference was observed, two distinct patterns of responding were detected-one predicted and the other unanticipated. Some strengths and limitations of the proposed hypothesis-assessment model are discussed in light of these results. PMID:8681511

  15. INTEGRATION OF STRENGTH AND CONDITIONING PRINCIPLES INTO A REHABILITATION PROGRAM

    PubMed Central

    Lorenz, Daniel S.

    2011-01-01

    Background and Purpose: Rehabilitation and strength and conditioning are often seen as two separate entities in athletic injury recovery. Traditionally an athlete progresses from the rehabilitation environment under the care of a physical therapist and/or athletic trainer to the strength and conditioning coach for specific return to sport training. These two facets of return to sport are often considered to have separate goals. Initial goals of each are often different due to the timing of their implementation encompassing different stages of post-injury recovery. The initial focus of post injury rehabilitation includes alleviation of dysfunction, enhancement of tissue healing, and provision of a systematic progression of range-of-motion and strength. During the return to function phases, specific return to play goals are paramount. Understanding of specific principles and program parameters is necessary when designing and implementing an athlete's rehabilitation program. Communication and collaboration amongst all individuals caring for the athlete is a must. The purpose of this review is to outline the current evidence supporting utilization of training principles in athletic rehabilitation, as well as provide suggested implementation of such principles throughout different phases of a proposed rehabilitation program. Evidence Acquisition: The following electronic databases were used to identify research relevant to this clinical commentary: MEDLINE (from 1950–June 2011) and CINAHL (1982–June 2011), for all relevant journal articles written in English. Additional references were accrued by independent searching of references from relevant articles. Results: Currently evidence is lacking in the integration of strength and conditioning principles into the rehabilitation program for the injured athlete. Numerous methods are suggested for possible utilization by the clinician in practice to improve strength, power, speed, endurance, and metabolic capacity

  16. Joy of cex: Sharpening the (t,He-3) probe at 345 MeV for the charge-exchange knife drawer

    NASA Astrophysics Data System (ADS)

    Howard, Meredith E.

    This data set represents the first step in a campaign of (t, 3He) charge-exchange experiments at the National Superconducting Cyclotron Laboratory designed explicitly to measure Gamow-Teller strength distributions in the electron capture direction for stable medium-heavy atomic nuclei, with particular interest in reaching the nuclei in the pf -shell or masses up to A=112. The 115 MeV/nucleon secondary triton beam with an average intensity of 4x106 pps on 10 mg/cm2 thick target foils produces 3He that are measured in the focal plane detectors of the S800 magnetic spectrometer. From these data, the scattering angle of the tritons is reconstructed to within 7 mrad and the energy of the recoil nucleus is reconstructed to better then 250 keV. Since there is no comprehensive study of the (t, 3He) probe for triton energies of 100-400 MeV/nucleon, this data is the first step in evaluating the advantages of extracting B(GT) from the (t,3He) probe over other hadronic probes. The first target is a CD2 target used for calibrating cross section. This is the third measurement for the (t, 3He) probe on 12C above 100 MeV/nucleon. The present 12C(t,3He) cross section for the 12B ground state (Jpi = 1 +) is lower than a previous measurement at the NSCL by more than one standard deviation in uncertainty but agrees with 12C( 3He,t)12N. This (t,3He) measurement for 24Mg, the second target, is the first above 100 MeV/nucleon. The B(GT) distribution for 24Na is extracted from differential cross sections as a function of residual nucleus excitation energy up to 7 MeV. For each peak in excitation energy, the differential cross section as a function of reconstructed scattering angle is extrapolated to zero degrees using angular distrubutions calculated with the distorted wave calculations from the code FOLD and transformed to q = 0 zero momentum transfer. Uncertainties in the B(GT) include a calculation of interference to Jpi=1 + expected from DeltaL=2, DeltaS=1 reactions. Comparisons of B

  17. Measurement of atmospheric turbulence strength by vortex beam

    NASA Astrophysics Data System (ADS)

    Gu, Yalong; Gbur, Greg

    2010-04-01

    The behavior of spatial correlation singularities suggests a possible method for measuring atmospheric turbulence strength with a vortex beam. The refractive index structure constant Cn2 can be obtained by measuring the radius of a ring dislocation of a vortex beam which has passed through atmospheric turbulence. An approximate analytic expression for the radius of a ring dislocation as a function of Cn2 has been derived, and its accuracy is verified by numerical examples.

  18. A review of floc strength and breakage.

    PubMed

    Jarvis, P; Jefferson, B; Gregory, J; Parsons, S A

    2005-09-01

    The main focus of the paper is to review current understanding of floc structure and strength. This has been done by reviewing current theoretical understanding of floc growth and breakage and an analysis of different techniques used for measuring floc strength. An overview has also been made of the general trends seen in floc strength analysis. The rate of floc formation is a balance between breakage and aggregation with flocs eventually reaching a steady-state size for a given shear rate. The steady-state floc size for a particular shear rate can, therefore, be a good indicator of floc strength. This has resulted in the development of a range of techniques to measure floc size at different applied shear levels using a combination of one or more of the following tools: light scattering and transmission; microscopy; photography; video and image analysis software. Floc strength may be simply quantified using the initial floc size for a given shear rate and the floc strength factor. More complex techniques have used theoretical modelling to determine whether flocs break by large-scale fragmentation or smaller-scale surface erosion effects, although this interpretation is open to debate. Impeller-based mixing, ultrasound and vibrating columns have all been used to provide a uniform, accurate and controllable dissipation of energy onto a floc suspension to determine floc strength. Other more recent techniques have used sensitive micromanipulators to measure the force required to break or compress individual flocs, although these techniques have been limited to the measurement of only a few hundred flocs. General trends emerge showing that smaller flocs tend to have greater strength than larger flocs, whilst the use of polymer seems to give increased strength to only some types of floc. Finally, a comparison of the strength of different types of floc (activated sludge flocs, organic matter flocs, sweep flocs and charge neutralised flocs) has been made highlighting

  19. Measurement of Fibrin Fiber Strength using AFM

    NASA Astrophysics Data System (ADS)

    Jawerth, Louise; Falvo, Mchael; Canning, Anthony; Matthews, Garrett; Superfine, Richard; Guthold, Martin

    2003-11-01

    Blood clots usually form in the event of injury or damage to blood vessels to prevent the loss of blood. Moreover, as we age, blood clots often form in undesired locations, i.e. in blood vessels around the heart or brain, or in uninjured vessels resulting in heart attacks or strokes. Fibrin fibers, the skeleton of a blood clot, essentially perform the mechanical task of creating a blockage that stems blood flow. Thus, a better understanding of the mechanical properties of these fibers, such as the tensile strength and Young's modulus, will enhance our understanding of blood clots. For quantitative stress and strain measurements, we need to image the deformation of the fiber and measure the applied force simultaneously. For this reason, we are combining fluorescent microscopy with atomic force microscopy. Fibrin fibers were fluorescently labeled with streptavidin-coated quantum dots and deposited on a functionalized glass substrate, imaged and manipulated under buffer. We will describe our progress in obtaining quantitative lateral force measurements under buffer simultaneous with strain measurements from optical microscope images.

  20. Evaluation of the ratio between uniaxial compressive strength and Schmidt hammer rebound number and its effectiveness in predicting rock strength

    NASA Astrophysics Data System (ADS)

    Selçuk, Levent; Yabalak, Esma

    2015-01-01

    Schmidt rebound hammer (SRH) test has been used worldwide as an index test for estimating the compressive strength and deformation characteristics of intact rocks. Although there is a high correlation between the surface hardness and the uniaxial compressive strength (UCS) of intact rocks, the SRH provides only a crude estimate for the UCS of rocks. SRH numbers reflect the outer surface of rocks and a depth of 30-50 mm. It is not sensitive to the intrinsic properties of the rocks such as texture, saturation, porosity and micro-fractures controlling the mechanical behaviour of rocks. In order for an empirical equation relating the surface hardness to the UCS to be widely used, the index parameter should characterise the mechanical properties of intact rocks. The ratio of UCS/SRH defined as a function of the UCS is a much better indicator for assessing the mechanical characteristics of rocks because the UCS of rocks defines the strength of the material and the ratio UCS/SRH is strongly affected by the level of the UCS. The ratio of UCS/SRH increases with increasing compressive strength at an increasing rate. A large-scale regression analysis was carried out using experimental data to evaluate the ratio of UCS/SRH for the rocks. The accuracy and reliability of the relationship was assessed by means of the root mean square error. The standard error associated with the empirical relationship is very small and the reliability and accuracy of the relationship to assess the compressive strength indirectly seem to be higher than those of traditional relationships between the UCS and the SRH. The ratio of UCS/SRH was also verified by a large database collected from previous studies. This strong linear relationship is proposed for engineering projects requiring the estimation of the compressive strength for intact rocks.