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Sample records for gamow-teller strength function

  1. Missing and Quenched Gamow-Teller Strength

    NASA Astrophysics Data System (ADS)

    Caurier, E.; Poves, A.; Zuker, A. P.

    1995-02-01

    Gamow-Teller strength functions in the resonance region are calculated in the full \\(pf\\)8 space. The observed profile is very sensitive to the level density and may become so diluted as to be confused with background. A model independent proof is given that standard quenching originates in nuclear correlations, and that some 30% of the total strength must be due to states outside the \\(pf\\)8 space. By combining this argument with the results of shell model calculations, comparison with the 48Ca\\(p,n\\)48Sc experimental data strongly suggest that most of the strength that is currently thought to be missing is actually observed.

  2. Gamow-Teller strength in 54Fe and 56Fe

    NASA Astrophysics Data System (ADS)

    Caurier, E.; Martínez-Pinedo, G.; Poves, A.; Zuker, A. P.

    1995-10-01

    Through a sequence of large scale 0ħω shell model calculations, Gamow-Teller strengths (S+ and S-) in 54Fe and 56Fe are obtained. They reproduce the experimental values by quenching the στ operator through the standard factor of 0.77. Comparisons are made with recent shell model Monte Carlo calculations. Results are shown to depend critically on the interaction. It is argued that the experimental data contain enough strength in the region above the resonance to make them consistent with the 3(N-Z) sum rule.

  3. Gamow-Teller transition strengths from 56Ni.

    PubMed

    Sasano, M; Perdikakis, G; Zegers, R G T; Austin, Sam M; Bazin, D; Brown, B A; Caesar, C; Cole, A L; Deaven, J M; Ferrante, N; Guess, C J; Hitt, G W; Meharchand, R; Montes, F; Palardy, J; Prinke, A; Riley, L A; Sakai, H; Scott, M; Stolz, A; Valdez, L; Yako, K

    2011-11-11

    A new technique to measure (p,n) charge-exchange reactions in inverse kinematics at intermediate energies on unstable isotopes was successfully developed and used to study the (56)Ni(p,n) reaction at 110 MeV/u. Gamow-Teller transition strengths from (56)Ni leading to (56)Cu were obtained and compared with shell-model predictions in the pf shell using the KB3G and GXPF1A interactions. The calculations with the GXPF1A interaction reproduce the experimental strength distribution much better than the calculations that employed the KB3G interaction, indicating deficiencies in the spin-orbit and proton-neutron residual potentials for the latter. The results are important for improving the description of electron-capture rates on nuclei in the iron region, which are important for modeling the late evolution of core-collapse and thermonuclear supernovae.

  4. Gamow-Teller strength in the beta decay of mirror nuclides

    NASA Astrophysics Data System (ADS)

    Honkanen, J.; ńystö, J.; Koponen, V.; Taskinen, P.; Eskola, K.; Messelt, S.; Ogawa, K.

    1987-12-01

    Distribution of the Gamow-Teller strength has been studied both experimentally and theoretically in the f7/2 shell mirror nuclides over a wide energy range. Experimental studies were performed using light ion induced reactions and the He-jet transport method or the ion-guide on-line isotope separation, IGISOL. Several transitions were observed to excited states in the decays of 43Ti and 51Fe and some in the decays of 47Cr, 49Mn, 43Co and 55Ni. Theoretical calculations were made by a shell model code using fn7/2+(P3/2, f5/2, P1/2)1 shell space. The β-feeding has been predicted for all transitions up to about 4 MeV excitation in each daughter nucleus. The quenching of the Gamow-Teller strength has been studied by comparing the experimental strength with the calculation. The formation of the giant Gamow-Teller resonance has been studied theoretically as a function of the mass number.

  5. Probing Configuration Mixing in Be-12 with Gamow-Teller Transition Strengths

    SciTech Connect

    Brown, B. A.; Howard, M. E.; Ratkiewicz, A.; Weisshaar, D.

    2012-01-01

    We present a novel technique for studying the quenching of shell gaps in exotic isotopes. The method is based on extracting Gamow-Teller ({Delta}L = 0, {Delta}S = 1) transition strengths [B(GT)] to low-lying states from charge-exchange reactions at intermediate beam energies. These Gamow-Teller strengths are very sensitive to configuration mixing between cross-shell orbitals, and this technique thus provides an important complement to other tools currently used to study cross-shell mixing. This work focuses on the N = 8 shell gap. We populated the ground and 2.24 MeV 0{sup +} states in {sup 12}Be using the {sup 12}B(1{sup +}) ({sup 7}Li, {sup 7}Be) reaction at 80 MeV/u in inverse kinematics. Using the ground-state B(GT) value from {beta}-decay measurements (0.184 {+-} 0.007) as a calibration, the B(GT) for the transition to the second 0{sup +} state was determined to be 0.214 {+-} 0.051. Comparing the extracted Gamow-Teller strengths with shell-model calculations, it was determined that the wave functions of the first and second 0{sup +} states in {sup 12}Be are composed of 25 {+-} 5% and 60 {+-} 5% (0s){sup 4}(0p){sup 8} configurations, respectively.

  6. Probing configuration mixing in 12Be with Gamow-Teller transition strengths.

    PubMed

    Meharchand, R; Zegers, R G T; Brown, B A; Austin, Sam M; Baugher, T; Bazin, D; Deaven, J; Gade, A; Grinyer, G F; Guess, C J; Howard, M E; Iwasaki, H; McDaniel, S; Meierbachtol, K; Perdikakis, G; Pereira, J; Prinke, A M; Ratkiewicz, A; Signoracci, A; Stroberg, S; Valdez, L; Voss, P; Walsh, K A; Weisshaar, D; Winkler, R

    2012-03-23

    We present a novel technique for studying the quenching of shell gaps in exotic isotopes. The method is based on extracting Gamow-Teller (ΔL=0, ΔS=1) transition strengths [B(GT)] to low-lying states from charge-exchange reactions at intermediate beam energies. These Gamow-Teller strengths are very sensitive to configuration mixing between cross-shell orbitals, and this technique thus provides an important complement to other tools currently used to study cross-shell mixing. This work focuses on the N=8 shell gap. We populated the ground and 2.24 MeV 0+ states in 12Be using the 12B(1+) (7Li, 7Be) reaction at 80  MeV/u in inverse kinematics. Using the ground-state B(GT) value from β-decay measurements (0.184±0.007) as a calibration, the B(GT) for the transition to the second 0+ state was determined to be 0.214±0.051. Comparing the extracted Gamow-Teller strengths with shell-model calculations, it was determined that the wave functions of the first and second 0+ states in 12Be are composed of 25±5% and 60±5% (0s)4(0p)8 configurations, respectively.

  7. 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.

  8. 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.

  9. 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.

  10. Impact of New Gamow-Teller Strengths on Explosive Type Ia Supernova Nucleosynthesis

    NASA Astrophysics Data System (ADS)

    Mori, Kanji; Famiano, Michael A.; Kajino, Toshitaka; Suzuki, Toshio; Hidaka, Jun; Honma, Michio; Iwamoto, Koichi; Nomoto, Ken'ichi; Otsuka, Takaharu

    2016-12-01

    Recent experimental results have confirmed a possible reduction in the Gamow-Teller (GT+) strengths of pf-shell nuclei. These proton-rich nuclei are of relevance in the deflagration and explosive burning phases of SNe Ia. While prior GT strengths result in nucleosynthesis predictions with a lower-than-expected electron fraction, a reduction in the GT+ strength can result in a slightly increased electron fraction compared to previous shell model predictions, though the enhancement is not as large as previous enhancements in going from rates computed by Fuller, Fowler, and Newman based on an independent particle model. A shell model parametrization has been developed that more closely matches experimental GT strengths. The resultant electron-capture rates are used in nucleosynthesis calculations for carbon deflagration and explosion phases of SNe Ia, and the final mass fractions are compared to those obtained using more commonly used rates.

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

    NASA Astrophysics Data System (ADS)

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

    2012-10-01

    A recent analysis of (p,n) and (n,p) reaction data from 90Zr 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 β- and the β+ 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.

  12. Ground state Gamow-Teller strength in sup 64 Ni(n,p) sup 64 Co

    SciTech Connect

    Ling, A.; Haight, R.C.; King, N.S.P.; Lisowski, P.W.; Sorenson, D.S.; Ullmann, J.L. ); Aslanoglou, X.; Finlay, R.W.; Park, B.K.; Rapaport, J. ); Brady, F.P.; Romero, J.L. ); Howell, C.R.; Tornow, W. )

    1991-01-01

    An important process occurring in presupernova stars is e{sup {minus}} capture on free protons and nuclei. As e{sup {minus}} capture and the charge exchange reaction (n,p) between same initial and final states are both T{sub 0} {yields} T{sub 0} + 1 transitions involving the same nuclear matrix element, the (n,p) reaction can be used to provide the input required to calculate e{sup {minus}} capture rates. Specifically, the e{sup {minus}} capture rate {lambda}{sup if} for a nucleus going from an initial state i to a final state f is proportional to the Gamow-Teller strength B{sup if}. Once B{sup if} for a particular transition is known, the corresponding e{sup {minus}} capture rate {lambda}{sup if} for that transition can be calculated. The unit cross section {cflx {sigma}}{sub GT}(E,A) relates B{sup if} to the zero degree differential cross section extrapolated to q = 0 for (n,p) or (p,n) reactions: {sigma}(q = 0) = {cflx {sigma}}(E,A)B{sup if}. As {cflx {sigma}}(E,A) has been seen to have a smooth A dependence, measurements of zero degree (n,p) cross sections for (fp) shell nuclei can be used to obtain B{sup if}, and thus {lambda}{sup if}, once a value for {cflx {sigma}}(E,A) in this mass region is known. The data presented here allow a value for {cflx {sigma}}{sub GT} in the (fp) shell to be calculated from the Gamow-Teller strength for the {beta}{sup {minus}} decay {sup 64}Co {yields} {sup 64}Ni + e{sup {minus}} + {bar {nu}}{sub e}. Since {sup 64}Co {beta}{sup {minus}} decay and the reaction {sup 64}Ni(n,p) {sup 64}Co have opposite initial and final states, detailed balance can be used to relate the Gamow-Teller strengths for the two processes: B{sup np} = 0.6228{sub {minus}.0369}{sup +.0328}. It is this value of B{sup np} together with the differential cross section measurements presented here for the reaction {sup 64}Ni(n,p) {sup 64}Co that allow {cflx {sigma}} to be calculated and thus a calibration point in the (fp) shell is established.

  13. Shell model description of Gamow-Teller strengths in pf-shell nuclei

    NASA Astrophysics Data System (ADS)

    Kumar, Vikas; Srivastava, P. C.

    2016-06-01

    A systematic shell model description of the experimental Gamow-Teller transition strength distributions in 42Ti , 46Cr , 50Fe and 54Ni is presented. These transitions have been recently measured via β -decay of these T_z=-1 nuclei, produced in fragmentation reactions at GSI and also with (3He, t) charge-exchange (CE) reactions corresponding to T_z=+1 to T_z=0 carried out at RCNP-Osaka. The calculations are performed in the pf model space, using the GXPF1a and KB3G effective interactions. Qualitative agreement is obtained for the individual transitions, while the calculated summed transition strengths closely reproduce the observed ones.

  14. Gamow-Teller strength distributions for {beta}{beta}-decaying nuclei within continuum quasiparticle random-phase approximation

    SciTech Connect

    Igashov, S. Yu.; Urin, M. H.; Rodin, Vadim; Faessler, Amand

    2011-04-15

    An isospin-self-consistent pn-continuum-QRPA approach is formulated and applied to describe the Gamow-Teller strength distributions for {beta}{beta}-decaying open-shell nuclei. Calculation results obtained for the pairs of nuclei {sup 76}Ge-Se, {sup 100}Mo-Ru, {sup 116}Cd-Sn, and {sup 130}Te-Xe are compared with available experimental data.

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

    SciTech Connect

    Fujita, Y.; Rubio, B.

    2007-06-13

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

  16. Gamow-teller strengths in proton-rich exotic nuclei deduced in the combined analysis of mirror transitions.

    PubMed

    Fujita, Y; Adachi, T; von Brentano, P; Berg, G P A; Fransen, C; De Frenne, D; Fujita, H; Fujita, K; Hatanaka, K; Jacobs, E; Nakanishi, K; Negret, A; Pietralla, N; Popescu, L; Rubio, B; Sakemi, Y; Shimbara, Y; Shimizu, Y; Tameshige, Y; Tamii, A; Yosoi, M; Zell, K O

    2005-11-18

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

  17. Gamow-Teller Strengths in Proton-Rich Exotic Nuclei Deduced in the Combined Analysis of Mirror Transitions

    SciTech Connect

    Fujita, Y.; Adachi, T.; Fujita, H.; Shimbara, Y.; Brentano, P. von; Fransen, C.; Pietralla, N.; Zell, K.O.; Berg, G.P.A.; Frenne, D. de; Jacobs, E.; Negret, A.; Popescu, L.; Fujita, K.; Hatanaka, K.; Nakanishi, K.; Sakemi, Y.; Shimizu, Y.; Tameshige, Y.; Tamii, A.

    2005-11-18

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

  18. Gamow-Teller strength distribution in proton-rich nucleus 57Zn and its implications in astrophysics

    NASA Astrophysics Data System (ADS)

    Nabi, Jameel-Un; Rahman, Muneeb-Ur

    2011-04-01

    Gamow-Teller (GT) transitions play a preeminent role in the collapse of stellar core in the stages leading to a Type-II supernova. The microscopically calculated GT strength distributions from ground and excited states are used for the calculation of weak decay rates for the core-collapse supernova dynamics and for probing the concomitant nucleosynthesis problem. The B(GT) strength for 57Zn is calculated in the domain of proton-neutron Quasiparticle Random Phase Approximation (pn-QRPA) theory. No experimental insertions were made (as usually made in other pn-QRPA calculations of B(GT) strength function) to check the performance of the model for proton-rich nuclei. The calculated B(GT) strength distribution is in good agreement with measurements and shows differences with the earlier reported shell model calculation. The pn-QRPA model reproduced the measured low-lying strength for 57Zn better in comparison to the KB3G interaction used in the large-scale shell model calculation. The stellar weak rates are sensitive to the location and structure of these low-lying states in daughter 57Cu. The structure of 57Cu plays a sumptuous role in the nucleosynthesis of proton-rich nuclei. The primary mechanism for producing such nuclei is the rp-process and is believed to be important in the dynamics of the collapsing supermassive stars. Small changes in the binding and excitation energies can lead to significant modifications of the predictions for the synthesis of proton rich isotopes. The β +-decay and electron capture (EC) rates on 57Zn are compared to the seminal work of Fuller, Fowler and Newman (FFN). The pn-QRPA calculated β +-decay rates are generally in good agreement with the FFN calculation. However at high stellar temperatures the calculated β +-decay rates are almost half of FFN rates. On the other hand, for rp-process conditions, the calculated electron capture ( β +-decay) rates are bigger than FFN rates by more than a factor 2 (1.5) and may have interesting

  19. Gamow-Teller strength and lepton captures rates on 66‑71Ni in stellar matter

    NASA Astrophysics Data System (ADS)

    Nabi, Jameel-Un; Majid, Muhammad

    Charge-changing transitions play a significant role in stellar weak-decay processes. The fate of the massive stars is decided by these weak-decay rates including lepton (positron and electron) captures rates, which play a consequential role in the dynamics of core collapse. As per previous simulation results, weak interaction rates on nickel (Ni) isotopes have significant influence on the stellar core vis-à-vis controlling the lepton content of stellar matter throughout the silicon shell burning phases of high mass stars up to the presupernova stages. In this paper, we perform a microscopic calculation of Gamow-Teller (GT) charge-changing transitions, in the β-decay and electron capture (EC) directions, for neutron-rich Ni isotopes (66‑71Ni). We further compute the associated weak-decay rates for these selected Ni isotopes in stellar environment. The computations are accomplished by employing the deformed proton-neutron quasiparticle random phase approximation (pn-QRPA) model. A recent study showed that the deformed pn-QRPA theory is well suited for the estimation of GT transitions. The astral weak-decay rates are determined over densities in the range of 10-1011g/cm3 and temperatures in the range of 0.01 × 109-30 × 109K. The calculated lepton capture rates are compared with the previous calculation of Pruet and Fuller (PF). The overall comparison demonstrates that, at low stellar densities and high temperatures, our EC rates are bigger by as much as two orders of magnitude. Our results show that, at higher temperatures, the lepton capture rates are the dominant mode for the stellar weak rates and the corresponding lepton emission rates may be neglected.

  20. Observation of the β-delayed γ-proton decay of (56)Zn and its impact on the Gamow-Teller strength evaluation.

    PubMed

    Orrigo, S E A; Rubio, B; Fujita, Y; Blank, B; Gelletly, W; Agramunt, J; Algora, A; Ascher, P; Bilgier, B; Cáceres, L; Cakirli, R B; Fujita, H; Ganioğlu, 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

    2014-06-06

    We report the observation of a very exotic decay mode at the proton drip line, the β-delayed γ-proton decay, clearly seen in the β decay of the T_{z}=-2 nucleus ^{56}Zn. Three γ-proton sequences have been observed after the β decay. Here this decay mode, already observed in the sd shell, is seen for the first time in the fp shell. Both γ and proton decays have been taken into account in the estimation of the Fermi and Gamow-Teller strengths. Evidence for fragmentation of the Fermi strength due to strong isospin mixing is found.

  1. Gamow-Teller strength in the exotic odd-odd nuclei 138La and 180Ta and its relevance for neutrino nucleosynthesis.

    PubMed

    Byelikov, A; Adachi, T; Fujita, H; Fujita, K; Fujita, Y; Hatanaka, K; Heger, A; Kalmykov, Y; Kawase, K; Langanke, K; Martínez-Pinedo, G; Nakanishi, K; von Neumann-Cosel, P; Neveling, R; Richter, A; Sakamoto, N; Sakemi, Y; Shevchenko, A; Shimbara, Y; Shimizu, Y; Smit, F D; Tameshige, Y; Tamii, A; Woosley, S E; Yosoi, M

    2007-02-23

    The Gamow-Teller strength distributions below the particle threshold in 138La and 180Ta, deduced from high-resolution measurements of the (3He,t) reaction at 0 degrees, 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 138La in the Universe can be made that way. Neutrino nucleosynthesis also contributes significantly to the abundance of 180Ta but the magnitude depends on the unknown branching ratio for population of the long-lived isomer.

  2. 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.

  3. Benchmarking nuclear models for Gamow-Teller response

    NASA Astrophysics Data System (ADS)

    Litvinova, E.; Brown, B. A.; Fang, D.-L.; Marketin, T.; Zegers, R. G. T.

    2014-03-01

    A comparative study of the nuclear Gamow-Teller response (GTR) within conceptually different state-of-the-art approaches is presented. Three nuclear microscopic models are considered: (i) the recently developed charge-exchange relativistic time blocking approximation (RTBA) based on the covariant density functional theory, (ii) the shell model (SM) with an extended “jj77” model space and (iii) the non-relativistic quasiparticle random-phase approximation (QRPA) with a Brueckner G-matrix effective interaction. We study the physics cases where two or all three of these models can be applied. The Gamow-Teller response functions are calculated for 208Pb, 132Sn and 78Ni within both RTBA and QRPA. The strengths obtained for 208Pb are compared to data that enable a firm model benchmarking. For the nucleus 132Sn, also SM calculations are performed within the model space truncated at the level of a particle-hole (ph) coupled to vibration configurations. This allows a consistent comparison to the RTBA where ph⊗phonon coupling is responsible for the spreading width and considerable quenching of the GTR. Differences between the models and perspectives of their future developments are discussed.

  4. 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.

  5. 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.

  6. 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.

  7. Sum rule study for double Gamow-Teller states

    NASA Astrophysics Data System (ADS)

    Sagawa, H.; Uesaka, T.

    2016-12-01

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

  8. Superallowed Gamow-Teller decay of the doubly magic nucleus 100Sn.

    PubMed

    Hinke, C B; Böhmer, M; Boutachkov, P; Faestermann, T; Geissel, H; Gerl, J; Gernhäuser, R; Górska, M; Gottardo, A; Grawe, H; Grębosz, J L; Krücken, R; Kurz, N; Liu, Z; Maier, L; Nowacki, F; Pietri, S; Podolyák, Zs; Sieja, K; Steiger, K; Straub, K; Weick, H; Wollersheim, H-J; Woods, P J; Al-Dahan, N; Alkhomashi, N; Ataç, A; Blazhev, A; Braun, N F; Čeliković, I T; Davinson, T; Dillmann, I; Domingo-Pardo, C; Doornenbal, P C; de France, G; Farrelly, G F; Farinon, F; Goel, N; Habermann, T C; Hoischen, R; Janik, R; Karny, M; Kaşkaş, A; Kojouharov, I M; Kröll, Th; Litvinov, Y; Myalski, S; Nebel, F; Nishimura, S; Nociforo, C; Nyberg, J; Parikh, A R; Procházka, A; Regan, P H; Rigollet, C; Schaffner, H; Scheidenberger, C; Schwertel, S; Söderström, P-A; Steer, S J; Stolz, A; Strmeň, P

    2012-06-20

    The shell structure of atomic nuclei is associated with 'magic numbers' and originates in the nearly independent motion of neutrons and protons in a mean potential generated by all nucleons. During β(+)-decay, a proton transforms into a neutron in a previously not fully occupied orbital, emitting a positron-neutrino pair with either parallel or antiparallel spins, in a Gamow-Teller or Fermi transition, respectively. The transition probability, or strength, of a Gamow-Teller transition depends sensitively on the underlying shell structure and is usually distributed among many states in the neighbouring nucleus. Here we report measurements of the half-life and decay energy for the decay of (100)Sn, the heaviest doubly magic nucleus with equal numbers of protons and neutrons. In the β-decay of (100)Sn, a large fraction of the strength is observable because of the large decay energy. We determine the largest Gamow-Teller strength so far measured in allowed nuclear β-decay, establishing the 'superallowed' nature of this Gamow-Teller transition. The large strength and the low-energy states in the daughter nucleus, (100)In, are well reproduced by modern, large-scale shell model calculations.

  9. Bivariate distributions in statistical spectroscopy studies: IV. Interacting particle Gamow-Teller strength densities and β-decay rates of fp-shell nuclei for presupernova stars

    NASA Astrophysics Data System (ADS)

    Kota, V. K. B.; Majumdar, D.

    1995-12-01

    A method to calculate temperature dependent β-decay rates is developed by writing the expression for the rates explicitly in terms of bivariate GT strength densities ( I {/O H } ( GT)) for a given hamiltonian H=h+V and state densities of the parent nucleus besides having the usual phase space factors. The theory developed in the preceding paper (III) for constructing NIP strength densities is applied for generating I {/O h } ( GT) and then I {/O H } ( GT) is constructed using the bivariate convolution form I {/O H } ( GT)=Σ S I {/O(GT) h,S }⊗ρ{/O(GT) V, S }; BIV-G . The spreading bivariate Gaussian ρ{/O(GT) V}; BIV-G, for fp-shell nuclei, is constructed by assuming that the marginal centroids are zero, the marginal variances are same as the corresponding state density variances and fixing the bivariate correlation coefficientbar ζ using experimental β-decay half lifes. With the deduced values ofbar ζ bar ζ ˜ 0.67, β-S-decay rates for61,62Fe and62 64Co isotopes are calculated at presupernova matter densities ρ=107 109 gm/cc, temperatures T=(3 5)×109 ∘K and electron fractions Ye=0.43 0.5. The convolution form for I {O(GT)/ H } led to a simple expression for calculating GT non-energy weighted sum rule strength and it describes (within 10%) the shell model results of fp-shell nuclei.

  10. Low-lying Gamow-Teller transitions in spherical nuclei

    SciTech Connect

    Cakmak, N.; Uenlue, S.; Selam, C.

    2012-01-15

    The Pyatov Method has been used to study the low-lying Gamow-Teller transitions in the mass region of 98 Less-Than-Or-Slanted-Equal-To A Less-Than-Or-Slanted-Equal-To 130. The eigenvalues and eigenfunctions of the total Hamiltonian have been solved within the framework of proton-neutron quasiparticle random-phase approximation. The low-lying {beta} decay log(ft) values have been calculated for the nuclei under consideration.

  11. 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.

  12. Hindered Gamow-Teller decay to the odd-odd N=Z (62)Ga: absence of proton-neutron T=0 condensate in A=62.

    PubMed

    Grodner, E; Gadea, A; Sarriguren, P; Lenzi, S M; Grebosz, J; Valiente-Dobón, J J; Algora, A; Górska, M; Regan, P H; Rudolph, D; de Angelis, G; Agramunt, J; Alkhomashi, N; Amon Susam, L; Bazzacco, D; Benlliure, J; Benzoni, G; Boutachkov, P; Bracco, A; Caceres, L; Cakirli, R B; Crespi, F C L; Domingo-Pardo, C; Doncel, M; Dombrádi, Zs; Doornenbal, P; Farnea, E; Ganioğlu, E; Gelletly, W; Gerl, J; Gottardo, A; Hüyük, T; Kurz, N; Leoni, S; Mengoni, D; Molina, F; Morales, A I; Orlandi, R; Oktem, Y; Page, R D; Perez, D; Pietri, S; Podolyák, Zs; Poves, A; Quintana, B; Rinta-Antila, S; Rubio, B; Nara Singh, B S; Steer, A N; Verma, S; Wadsworth, R; Wieland, O; Wollersheim, H J

    2014-08-29

    Search for a new kind of superfluidity built on collective proton-neutron pairs with aligned spin is performed studying the Gamow-Teller decay of the T=1, J(π)=0+ ground state of (62)Ge into excited states of the odd-odd N=Z nucleus (62)Ga. The experiment is performed at GSI Helmholtzzentrum für Shwerionenforshung with the (62)Ge ions selected by the fragment separator and implanted in a stack of Si-strip detectors, surrounded by the RISING Ge array. A half-life of T1/2=82.9(14)  ms is measured for the (62)Ge ground state. Six excited states of (62)Ga, populated below 2.5 MeV through Gamow-Teller transitions, are identified. Individual Gamow-Teller transition strengths agree well with theoretical predictions of the interacting shell model and the quasiparticle random phase approximation. The absence of any sizable low-lying Gamow-Teller strength in the reported beta-decay experiment supports the hypothesis of a negligible role of coherent T=0 proton-neutron correlations in (62)Ga.

  13. 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.

  14. Observation of low- and high-energy Gamow-Teller phonon excitations in nuclei.

    PubMed

    Fujita, Y; Fujita, H; Adachi, T; Bai, C L; Algora, A; Berg, G P A; von Brentano, P; Colò, G; Csatlós, M; Deaven, J M; Estevez-Aguado, E; Fransen, C; De Frenne, D; Fujita, K; Ganioğlu, E; Guess, C J; Gulyás, J; Hatanaka, K; Hirota, K; Honma, M; Ishikawa, D; Jacobs, E; Krasznahorkay, A; Matsubara, H; Matsuyanagi, K; Meharchand, R; Molina, F; Muto, K; Nakanishi, K; Negret, A; Okamura, H; Ong, H J; Otsuka, T; Pietralla, N; Perdikakis, G; Popescu, L; Rubio, B; Sagawa, H; Sarriguren, P; Scholl, C; Shimbara, Y; Shimizu, Y; Susoy, G; Suzuki, T; Tameshige, Y; Tamii, A; Thies, J H; Uchida, M; Wakasa, T; Yosoi, M; Zegers, R G T; Zell, K O; Zenihiro, J

    2014-03-21

    Gamow-Teller (GT) transitions in atomic nuclei are sensitive to both nuclear shell structure and effective residual interactions. The nuclear GT excitations were studied for the mass number A = 42, 46, 50, and 54 "f-shell" nuclei in ((3)He, t) charge-exchange reactions. In the (42)Ca → (42)Sc reaction, most of the GT strength is concentrated in the lowest excited state at 0.6 MeV, suggesting the existence of a low-energy GT phonon excitation. As A increases, a high-energy GT phonon excitation develops in the 6-11 MeV region. In the (54)Fe → (54)Co reaction, the high-energy GT phonon excitation mainly carries the GT strength. The existence of these two GT phonon excitations are attributed to the 2 fermionic degrees of freedom in nuclei.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. Gamow-Teller Transitions Starting from T{sub z} = +3/2 Nucleus {sup 47}Ti

    SciTech Connect

    Ganioglu, E.; Susoy, G.; 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.; Gulyas, J.

    2011-10-28

    Gamow-Teller (GT) transitions are mediated by the {sigma}{tau} 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 {sup 47}Ti in a high-resolution ({sup 3}He,t) charge-exchange reactions at 0 deg. 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 T{sub z} = {+-}3/2{yields}{+-}1/2 analogous GT transitions, we can deduce the detailed strength distribution starting from mirror unstable nucleus {sup 47}Mn.

  20. Measurement of Gamow-Teller transitions from 56Ni

    NASA Astrophysics Data System (ADS)

    Sasano, Masaki

    2011-10-01

    Electron-capture (EC) and β-decay play important roles in type-II and type-Ia supernovae. They occur through the Gamow-Teller (GT) and Fermi transitions in nuclei, which are extensively studied to reliably estimate the weak-interactions rates. Experimentally, a powerful probe to study GT transitions has been provided by the charge-exchange reactions at intermediate energies such as the (p,n), (3He,t) rections. They can selectively excite the GT transitions in a wide excitation energy region. Until recently, such studies have been restricted to stable nuclei because of difficulties in inverse-kinematics measurements with rare isotope beams. In this talk, we present the first study with a rare isotope using the 56Ni(p,n)56Cu reaction at 110 MeV/u in inverse kinematics with a newly developed Low-Energy Neutron Detector Array (LENDA) in combination with the S800 spectrometer. 56Ni is produced in large abundances during the pre-explosion phase of core-collapse supernovae and considered to be as one of the most important contributors to the change in the electron-to-baryon ratio in core-collapse supernovae. In addition, to study the GT transition in 56Ni serves as a stringent test of the effects of the N = Z = 28 core not being inert on GT transitions for a large number of nearby nuclei in the Fe region. This work is supported by the US NSF (PHY-0822648 (JINA) and PHY-0606007).

  1. Shell-model calculations of isovector electromagnetic transitions and Gamow-Teller beta decays in the N~=28 region

    NASA Astrophysics Data System (ADS)

    Yokoyama, Atsushi; Horie, Hisashi

    1988-08-01

    Isovector E2 and M1 transitions from isobaric analog states of the N=29 isotones to low-lying states in the N=28 isotones are discussed by making use of the shell model. The fn-17/2j and the fn7/2+fn-17/2j configurations are assumed for the N=29 and N=28 isotones, respectively, where j denotes one of the p3/2, p1/2, and f5/2 orbits. First, the model space is restricted to j=p3/2 only, and it is extended to include all the p3/2, p1/2, and f5/2 orbits, in order to study stepwise the role of the various wave function components. For the isovector E2 transitions, it is confirmed that the major components of the wave functions play a decisive role for the allowed transitions in the single-particle shell model and the use of the good isospin wave functions is indispensable for the forbidden ones. For the isovector M1 transitions, it is shown that the spin-nonflip f7/2-->f7/2 transition, which is introduced by the neutron-excited components in the wave functions of the N=28 isotones, plays a very significant role: It gives rise to the important cancellation which is responsible for the strong suppression of the M1 transition strength in comparison with the simple shell-model prediction, and it becomes the leading term in the l- and j-forbidden M1 transitions. Similar discussion holds for the Gamow-Teller beta decays between the levels of the N=28 and N=29 nuclei.

  2. 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.

  3. Gamow-Teller transitions from Mg24 and their impact on the electron capture rates in the O+Ne+Mg cores of stars

    NASA Astrophysics Data System (ADS)

    Nabi, Jameel-Un; Rahman, Muneeb-Ur

    2007-03-01

    Electron captures on nuclei play an important role in the collapse of stellar core in the stages leading to a type-II supernova. Recent observations of subluminous Type II-P supernovae (e.g., 2005cs, 2003gd, 1999br) were able to rekindle the interest in 8 10 M⊙ which develop O+Ne+Mg cores. We used the proton-neutron quasiparticle random phase approximation (pn-QRPA) theory to calculate the B(GT) strength for Mg24 →Na24 and its associated electron capture rates for incorporation in simulation calculations. The calculated rates, in this article, have differences with the earlier reported shell model and Fuller, Fowler, and Newman (hereafter FN2) rates. We compared Gamow-Teller (GT) strength distribution functions and found fairly good agreement with experiment and shell model. However, the GT centroid and the total GT strength, which are useful in the calculation of electron capture rates in the core of massive presupernova stars, lead to the enhancement of our rate up to a factor of 4 compared to the shell model rates at high temperatures and densities.

  4. 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.

  5. Comparison of the pn quasiparticle RPA and shell model for Gamow-Teller beta and double-beta decays

    NASA Astrophysics Data System (ADS)

    Zhao, Liang; Brown, B. Alex

    1993-06-01

    We examine the validity of the pn quasiparticle RPA (pnQRPA) as a model for calculating β+ and 2νββ Gamow-Teller decays by making a comparison of the pnQRPA with a large-basis shell-model calculation within the 0f1p shell. We employ A=46 nuclei (those with six valence nucleons) for this comparison. Our comparison includes the decay matrix elements summed over final states, the strength distributions, and, for the first time, the coherent transition matrix elements (CTME). The pnQRPA overestimates the total β+ and 2νββ matrix elements. There are large differences in the shape of the spectra as well as in the CTME between the pnQRPA and shell-model results. Empirical improvements for the pnQRPA are discussed.

  6. Comparison of the [ital pn] quasiparticle RPA and shell model for Gamow-Teller beta and double-beta decays

    SciTech Connect

    Zhao, L.; Brown, B.A. )

    1993-06-01

    We examine the validity of the [ital pn] quasiparticle RPA ([ital pn]QRPA) as a model for calculating [beta][sup +] and 2[nu][beta][beta] Gamow-Teller decays by making a comparison of the [ital pn]QRPA with a large-basis shell-model calculation within the 0[ital f]1[ital p] shell. We employ [ital A]=46 nuclei (those with six valence nucleons) for this comparison. Our comparison includes the decay matrix elements summed over final states, the strength distributions, and, for the first time, the coherent transition matrix elements (CTME). The [ital pn]QRPA overestimates the total [beta][sup +] and 2[nu][beta][beta] matrix elements. There are large differences in the shape of the spectra as well as in the CTME between the [ital pn]QRPA and shell-model results. Empirical improvements for the [ital pn]QRPA are discussed.

  7. Gamow-Teller response and its spreading mechanism in doubly magic nuclei

    NASA Astrophysics Data System (ADS)

    Niu, Y. F.; Colò, G.; Vigezzi, E.

    2014-11-01

    The scope of the paper is to apply a state-of-the-art beyond mean-field model to the description of the Gamow-Teller response in atomic nuclei. This topic recently attracted considerable renewed interest, due, in particular, to the possibility of performing experiments in unstable nuclei. We study the cases of 48Ca,78Ni,132Sn, and 208Pb. Our model is based on a fully self-consistent Skyrme Hartree-Fock plus random phase approximation. The same Skyrme interaction is used to calculate the coupling between particles and vibrations, which leads to the mixing of the Gamow-Teller resonance with a set of doorway states and to its fragmentation. We compare our results with available experimental data. The microscopic coupling mechanism is also discussed in some detail.

  8. Estimation of a 2p2h effect on Gamow-Teller transitions within the second Tamm-Dancoff approximation

    NASA Astrophysics Data System (ADS)

    Minato, F.

    2016-04-01

    Two-particle two-hole (2p2h) effect on the Gamow-Teller (GT) transition for neutron-rich nuclei is studied by the second Tamm-Dancoff approximation (STDA) with the Skyrme interaction. Unstable 24O and 34Si and stable 48Ca nuclei are chosen to study the quenching and fragmentation of the GT strengths. Correlation of the 2p2h configurations causes about 20 % quenching and downward shift of GT giant resonances (GTGRs). The residual interaction changing relative angular momentum that appeared in the tensor force part gives a meaningful effect to the GT strength distributions. In this work, 17 - 26 % of the total GT strengths are brought to high-energy region above GTGRs. In particular, the tensor force brings strengths to high energy more than 50 MeV. STDA calculation within a small model space for 2p2h configuration is also performed and experimental data of 48Ca is reproduced reasonably.

  9. 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.

  10. 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.

  11. Study of Gamow-Teller transitions from 132Sn via the (p,n) reaction at 220 MeV/u in inverse kinematics

    NASA Astrophysics Data System (ADS)

    Sasano, M.; Yasuda, J.; Zegers, R. G. T.; Baba, H.; Chao, W.; Dozono, M.; Fukuda, N.; Inabe, N.; Isobe, T.; Jhang, G.; Kamaeda, D.; Kubo, T.; Kurata-Nishimura, M.; Milman, E.; Motobayashi, T.; Otsu, H.; Panin, V.; Powell, W.; Sakai, H.; Sako, M.; Sato, H.; Shimizu, Y.; Stuhl, L.; Suzuki, H.; Tangwancharoen, S.; Takeda, H.; Uesaka, T.; Yoneda, K.; Zenihiro, J.; Kobayashi, T.; Sumikama, T.; Tako, T.; Nakamura, T.; Kondo, Y.; Togano, Y.; Shikata, M.; Tsubota, J.; Yako, K.; Shimoura, K.; Ota, S.; Kawase, S.; Kubota, Y.; Takaki, M.; Michimasa, S.; Kisamori, K.; Lee, C. S.; Tokieda, H.; Kobayashi, M.; Koyama, S.; Kobayashi, N.; Wakasa, T.; Sakaguchi, S.; Krasznahorkay, A.; Murakami, T.; Nakatsuka, N.; Kaneko, M.; Matsuda, Y.; Mucher, D.; Reichert, S.; Bazin, D.; Lee, J. W.

    2016-01-01

    The charge-exchange (p,n) reaction at 220 MeV has been measured to extract the strength distribution of Gamow-Teller transitions from the doubly magic unstable nucleus 132Sn. A recently developed experimental technique of measuring the (p,n) reaction in inverse kinematics has been applied to the study of unstable nuclei in the mass region around A˜100 for the first time. We have combined the low-energy neutron detector WINDS and the SAMURAI spectrometer at the RIKEN radioactive isotope beam factory (RIBF). The particle identification plot for the reaction residues obtained by the spectrometer provides the clear separation of the CE reaction channel from other background events, enabling us to identify kinematic curves corresponding the (p, n) reaction. Further analysis to reconstruct the excitation energy spectrum is ongoing.

  12. 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.

  13. 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.

  14. 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.

  15. Effects of deformation and neutron-proton pairing on the Gamow-Teller transitions for Mg,2624 in a deformed quasiparticle random-phase approximation

    NASA Astrophysics Data System (ADS)

    Ha, Eunja; Cheoun, Myung-Ki

    2016-11-01

    We investigate effects of neutron-proton (n p ) pairing correlations on the Gamow-Teller (GT) transition of Mg,2624 by explicitly taking into account deformation effects. Our calculation is performed by a deformed quasiparticle random phase approximation (DQRPA) which includes the deformation at the Bardeen-Cooper-Schrieffer and RPA stage. In this paper, we include the n p pairing as well as neutron-neutron (n n ) and proton-proton (p p ) paring correlations to the DQRPA. Our new formalism is applied to the GT transition of well-known deformed Mg isotopes. The n p pairing effect is found to affect more or less the GT distribution of 24Mg and 26Mg. But the deformation effect turns out to be much larger than the n p paring effect because the Fermi surfaces smear more widely by the deformation rather than the n p pairing correlations. Correlations between the deformation and the n p pairing effects and their ambiguities are also discussed with the comparison to experimental GT strength data by triton and 3He beams.

  16. Neutron-Proton Pairing Effects on the Gamow-Teller Transitions in 24,26Mg by Using the Deformed QRPA

    NASA Astrophysics Data System (ADS)

    Ha, Eunja; Cheoun, Myung-Ki

    We investigated the effects of the neutron-proton (np) pairing correlations on the Gamow-Teller (GT) transition of 24,26Mg by taking into account the deformation. Our calculations is performed within the deformed quasi-particle random phase approximation (DQRPA) which explicitly includes the deformation at the BCS and RPA stage. In this work, we include the np pairing as well as the nn and pp paring correlations to the DQRPA. Our new formalism is applied to the GT transition of the well known deformed Mg isotopes. The np pairing effect is found to affect the GT distribution of 24Mg and 26Mg. Correlations between the deformation and the np pairing are also discussed with the comparison to the experimental GT transition data by triton and 3He beams.

  17. High-resolution study of {sup 56}Fe{yields}{sup 56}Mn Gamow-Teller transition by the combined analysis of {sup 56}Fe({sup 3}He, t){sup 56}Co and 56Fe(P, p'){sup 56}Fe reactions

    SciTech Connect

    Nagashimaa, M.; Shimbara, Y.; Fujita, H.; Fujita, Y.; Adachi, T.; Hatanaka, K.; Hirota, K.; Matsubara, H.; Nakanishi, K.; Okamura, H.; Ong, H. J.; Sakemic, Y.; Shimizu, Y.; Suzuki, T.; Tamii, A.; Yosoi, M.; Botha, N. T.; Neveling, R.; Ganioglu, E.; Susoy, G.

    2010-08-12

    The Gamow-Teller (GT) transitions in the {beta}{sup +}(electron capture) direction from the ground state of {sup 56}Fe to the excited states of {sup 56}Mn play an important role in the core collapse of presupernova. Assuming that isospin analogous transitions in isobars have corresponding strengths, we deduced these GT strengths by combining the results of the {sup 56}Fe(p, p'){sup 56}Fe experiment performed at 200 MeV and 0 deg. and the {sup 56}Fe({sup 3}He, t){sup 56}Co experiment in the {beta}{beta} direction at 140 MeV/u and 0 deg. The ground state of {sup 56}Fe has the isospin value of T = 2, while the GT states in {sup 56}Mn have T = 3. In order to identify the analogous T = 2{yields}3, GT transitions in the {sup 56}Fe(p, p'){sup 56}Fe and the {sup 56}Fe({sup 3}He, t){sup 56}Co measurements, we used the fact that the isospin Clebsch-Gordan (CG) coefficients for these T = 2{yields}3 transitions are different in these measurements. Then the GT transition strengths B(GT) in the {beta}{sup +} direction can be deduced from the B(GT) values of the corresponding transitions well determined in the {sup 56}Fe({sup 3}He, t){sup 56}Co measurement assuming the isospin symmetry and correcting the difference of CG coefficients.

  18. Search for magnetic dipole strength and giant spin-flip resonances in heavy nuclei. [120 to 200 MeV

    SciTech Connect

    Horen, D J

    1980-01-01

    A description is given of the use of high-resolution (n,n) scattering and the (p,n) reaction as tools to investigate highly excited states, with emphasis on information pertaining to magnetic dipole strength and giant spin-flip resonances in heavy nuclei. It is shown how the ability to determine uniquely the spins and parities of resonances observed in neutron scattering has been instrumental to an understanding of the distribution of M1 strength in /sup 207/ /sup 208/Pb. Some recent results of (p,n) studies with intermediate energy protons are discussed. Energy systematics of the giant Gamow-Teller (GT) resonance as well as new ..delta..l = ..delta..S = 1 resonance with J/sup ..pi../ = (1,2)/sup -/ are presented. It is shown how the (p,n) reaction might be useful in locating M1 strength in heavy nuclei. 20 figures.

  19. Radiative Strength Functions and Level Densities

    SciTech Connect

    Schiller, A; Becker, J A; Bernstein, L A; Voinov, A; Guttormsen, M; Hjorth-Jensen, M; Rekstad, J; Siem, S; Mitchell, G E; Tavukcu, E

    2002-08-28

    Radiative strength functions and level densities have been extracted from primary {gamma}-ray spectra for {sup 27,28}Si, {sup 56,57}Fe, {sup 96,97}Mo, and several rare earth nuclei. An unexpectedly strong ({approx} 1 mb MeV) resonance at 3 MeV in the radiative strength function has been observed for well-deformed rare earth nuclei. The physical origin of this resonance and its connection to the scissors mode is discussed.

  20. 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.

  1. Measurement of the Gamow-Teller Branching Ratio in the β-Decay of 21Na

    NASA Astrophysics Data System (ADS)

    Achouri, N. L.; Angélique, J.-C.; Ban, G.; Bastin, B.; Blank, B.; Dean, S.; Dendooven, P. G.; Giovinazzo, J.; Grévy, S.; Jungmann, K.; Laurent, B.; Liénard, E.; Naviliat-Cuncic, O.; Orr, N. A.; Rogachevskiy, A.; Sohani, M.; Traykov, E.; Wilschut, H.

    2009-01-01

    The β-decay branching ratio of the GT transition in 21Na to the first excited state in 21Ne has been measured. The value obtained of 4.93(20)% is in agreement with the most recent measurement and with the value adopted so far. This confirms that the branching ratio is not the source of discrepancy in a previous measurement of β-v correlation coefficient which exhibited a 3σ difference with respect to the Standard Model prediction.

  2. Bivariate distributions in statistical spectroscopy studies: III. Non interacting particle strength densities for one-body transition operators

    NASA Astrophysics Data System (ADS)

    Kota, V. K. B.; Majumdar, D.

    1995-12-01

    In statistical spectroscopy, it was shown by French et al. (Ann. Phys., N.Y. 181, 235 (1988)) that the bivariate strength densities take a convolution form with the non interacting particle (NIP) strength density being convoluted with a spreading bivariate Gaussian due to interactions. Leaving aside the question of determining the parameters of the spreading bivariate Gaussian, one needs good methods for constructing the NIP bivariate strength densities I {O/ h }( E,E') ( h is a one-body hamiltonian and O is a transition operator) in large shell model spaces. A formalism for constructing I {O/ h } is developed for one-body transition operators by using spherical orbits and spherical configurations. For rapid construction and also for applying the statistical theory in large shell model spaces I {O/ h } is decomposed into partial densities defined by unitary orbit configurations (unitary orbit is a set of spherical orbits). Trace propagation formulas for the bivariate moments M rs with r+s ≤2 of the partial NIP strength densities, which will determine the Gaussian representation, are derived. In a large space numerical example with Gamow-Teller β - transition operator, the superposition of unitary orbit partial bivariate Gaussian densities is shown to give a good representation of the exact NIP strength densities. Trace propagation formulas for M rs with r+<—4 are also derived in m-particle scalar spaces which are useful for many purposes.

  3. 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).

  4. 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

  5. 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.

  6. Systematics of strength function sum rules

    NASA Astrophysics Data System (ADS)

    Johnson, Calvin W.

    2015-11-01

    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 expects sum rules to evolve with excitation energy. Furthermore, to lowest order the slope of the secular evolution can be traced to a component of the Hamiltonian being positive (repulsive) or negative (attractive).

  7. Photon strength functions from photon scattering

    NASA Astrophysics Data System (ADS)

    Schwengner, Ronald

    2015-10-01

    We present photon-scattering experiments using bremsstrahlung at the γELBE facility of Helmholtz-Zentrum Dresden-Rossendorf (HZDR) and using quasi-monoenergetic, polarized γ rays at the HI γS facility of the Triangle Universities Nuclear Laboratory (TUNL) in Durham. In the analysis of the spectra measured by using bremsstrahlung at γELBE, we include intensity in the quasi-continuum and perform simulations of statistical γ-ray cascades using the code γDEX to estimate intensities of inelastic transitions to low-lying excited states. Simulated average branching ratios are compared with model-independent branching ratios obtained from spectra measured by using monoenergetic γ beams at HI γS. Photoabsorption cross sections deduced in this way are presented for selected nuclides. Strength in the energy region of the so-called pygmy dipole resonance (PDR) is considered in nuclei around mass 80 and in xenon isotopes. In collaboration with Ralph Massarczyk, Los Alamos National Laboratory.

  8. Gamma-ray strength functions and their relation to astrophysics

    SciTech Connect

    Larsen, A. C.; Buerger, A.; Guttormsen, M.; Hagen, T. W.; Nyhus, H. T.; Rekstad, J. B.; Renstroem, T.; Rose, S. J.; Ruud, I. E.; Siem, S.; Syed, N. U. H.; Toft, H. K.; Tveten, G. M.; Wikan, K.; Algin, E.; Agvaanluvsan, U.; Goergen, A.

    2011-10-28

    The nuclear {gamma}-ray strength function is one of the indispensable inputs needed for reaction-rate calculations, and is particularly important for the neutron-capture cross section. The nuclear physics group at the Oslo Cyclotron Laboratory has developed a method to extract simultaneously nuclear level density and {gamma}-ray strength function from particle-{gamma} coincidence measurements. Data on the strength functions of Sn nuclei as well as for lighter elements are presented. The Sn isotopes all display a resonance-like structure close to the neutron threshold, that could possibly be due to the neutron-skin oscillation mode. This so-called pygmy dipole resonance greatly influences the neutron-capture rates. In the lighter nuclei, an enhancement of the strength function at low {gamma} energies is observed. The possible impact of this increase on Maxwellian-averaged reaction rates has been investigated.

  9. Gamma-ray strength functions and their relation to astrophysics

    NASA Astrophysics Data System (ADS)

    Larsen, A. C.; Goriely, S.; Algin, E.; Agvaanluvsan, U.; Bürger, A.; Görgen, A.; Guttormsen, M.; Hagen, T. W.; Lönnroth, T.; Mitchell, G. E.; Nyhus, H. T.; Rekstad, J. B.; Renstrøm, T.; Rose, S. J.; Ruud, I. E.; Schiller, A.; Siem, S.; Syed, N. U. H.; Toft, H. K.; Tveten, G. M.; Voinov, A.; Wikan, K.

    2011-10-01

    The nuclear γ-ray strength function is one of the indispensable inputs needed for reaction-rate calculations, and is particularly important for the neutron-capture cross section. The nuclear physics group at the Oslo Cyclotron Laboratory has developed a method to extract simultaneously nuclear level density and γ-ray strength function from particle-γ coincidence measurements. Data on the strength functions of Sn nuclei as well as for lighter elements are presented. The Sn isotopes all display a resonance-like structure close to the neutron threshold, that could possibly be due to the neutron-skin oscillation mode. This so-called pygmy dipole resonance greatly influences the neutron-capture rates. In the lighter nuclei, an enhancement of the strength function at low γ energies is observed. The possible impact of this increase on Maxwellian-averaged reaction rates has been investigated.

  10. Full pf shell model study of A=48 nuclei

    NASA Astrophysics Data System (ADS)

    Caurier, E.; Zuker, A. P.; Poves, A.; Martínez-Pinedo, G.

    1994-07-01

    Exact diagonalizations with a minimally modified realistic force lead to detailed agreement with measured level schemes and electromagnetic transitions in 48Ca, 48Sc, 48Ti, 48V, 48Cr, and 48Mn. Gamow-Teller strength functions are systematically calculated and reproduce the data to within the standard quenching factor. Their fine structure indicates that fragmentation makes much strength unobservable. As a by-product, the calculations suggest a microscopic description of the onset of rotational motion. The spectroscopic quality of the results provides strong arguments in favor of the general validity of monopole corrected realistic forces, which is discussed.

  11. Shell-model calculations of beta-decay rates for s- and r-process nucleosyntheses

    NASA Astrophysics Data System (ADS)

    Takahashi, K.; Mathews, G. J.; Bloom, S. D.

    1985-10-01

    Examples of large-basis shell-model calculations of Gamow-Teller (BETA)-decay properties of specific interest in the astrophysical s- and r- processes are presented. Numerical results are given for: (1) the GT-matrix elements for the excited state decays of the unstable s-process nucleus Tc-99; and (2) the GT-strength function for the neutron-rich nucleus Cd-130, which lies on the r-process path. The results are discussed in conjunction with the astrophysics problems.

  12. Beta-decay rates: towards a self-consistent approach

    SciTech Connect

    Borzov, I. N.; Goriely, S.; Pearson, J. M.

    1998-02-15

    An approximation to a self-consistent model of the ground state properties and spin-isospin excitations of neutron-rich nuclides is outlined. The structure of the Gamow-Teller strength functions in stable nuclei and short-lived nuclides undergoing high-energy {beta}-decay is discussed. The results of large-scale calculations of the {beta}-decay rates for spherical and slightly deformed nuclides of relevance to the r-process are analysed and compared with the results of existing global calculations.

  13. 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.

  14. 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.

  15. 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)

  16. 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

  17. 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

  18. 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.

  19. 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.

  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. Functional outcomes associated with expiratory muscle strength training: narrative review.

    PubMed

    Laciuga, Helena; Rosenbek, John C; Davenport, Paul W; Sapienza, Christine M

    2014-01-01

    This review presents the available evidence for the effects of expiratory muscle strength training (EMST) with the use of a pressure threshold device. The investigators used computerized database searches for studies reporting the outcomes of pressure threshold EMST published after 1994. A total of 24 selected articles presented outcomes related but not limited to respiratory function, such as speech, swallow, voice, and cough function in persons with neurologic conditions such as Parkinson disease, multiple sclerosis, and Lance-Adams syndrome; in persons with respiratory diseases, such as chronic obstructive pulmonary disease; and in healthy young adults and sedentary and active elderly. Several studies demonstrated promising outcomes of EMST as a non-task-specific training for airway protection in persons with dysphagia secondary to neuromuscular impairments; however, further research is needed to confirm and generalize the reported findings.

  2. 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.

  3. {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.

  4. 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.

  5. 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.

  6. Radiative Strength Functions in 172Yb below 8 Me V

    SciTech Connect

    Schiller, A; Becker, J A; Bernstein, L A; Garrett, P E; Hill, T S; McNabb, D P; Younes, W; Tavukcu, E; Vomov, A; Guttormsen, M; Rekstad, J; Siem, S

    2002-02-06

    We have measured prompt {gamma} rays after thermal and resonant neutron capture in {sup 171}Yb. The {gamma} rays were measured with three high resolution ({approx}3 keV) and high efficiency (two {approx}80% Ge(HP) and one {approx}200% segmented Clover) detectors. We have obtained singles and two-fold coincidence spectra as function of neutron energy using the time-of-flight technique. Two-fold coincidences where the summed energy adds up to the neutron binding energy B{sub n} or to B{sub n} minus the energy of the first excited stated ({approx}79 keV) will be used to determine the multipolarity of the pygmy resonance in {sup 172}Yb. This pygmy resonance is a resonant structure in the radiative strength function around {approx}3 MeV in deformed rare earth nuclei [1]. The following goals were met: (1) We have shown the feasibility of prompt, high-resolution {gamma} spectroscopy at FP14 after thermal as well as resonant neutron capture. (2) Online analysis shows that sufficient statistics ({approx}7000 counts) are expected in each of the two relevant peaks in the summed-energy spectrum. Analysis of the experiment is in progress. It still remains to show that the multipolarity of the pygmy resonance can be determined experimentally from two-step cascade intensities.

  7. 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.

  8. 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

  9. Absolute vs. relative machine strength as predictors of function in older adults.

    PubMed

    Knutzen, Kathleen M; Brilla, Lorraine; Caine, Dennis; Chalmers, Gordon; Gunter, Kathy; Schot, Philip

    2002-11-01

    This study examined the relationship between absolute and relative (1 repetition maximum/LBM) strength vs. 13 different functional measurements in 143 older adults (mean = 70.28, standard deviation = 7.90 years). Strength for 11 machine lifts was determined using a predicted 1-repetition maximal strength measurement. Zero-order correlation results between absolute and relative strength vs. function measures demonstrated very weak to moderate correlations in the range of 0.02-0.57 and 0.01-0.44, respectively, with the lowest correlations present between strength and balance measures and the highest correlations present between strength and the carrying task (p functional tasks using strength measures, with absolute and relative strength measures accounting for only 3-38% and 3-33% of the various functional measures, respectively. This study identified specific strength measurements that contribute to the variance in a functional task but also clearly indicated that strength alone cannot serve as a predictor of function in older adults.

  10. Effects of strength training on muscle strength characteristics, functional capabilities, and balance in middle-aged and older women.

    PubMed

    Holviala, Jarkko H S; Sallinen, Janne M; Kraemer, William J; Alen, Markku J; Häkkinen, Keijo K T

    2006-05-01

    Progressive strength training can lead to substantial increases in maximal strength and mass of trained muscles, even in older women and men, but little information is available about the effects of strength training on functional capabilities and balance. Thus, the effects of 21 weeks of heavy resistance training--including lower loads performed with high movement velocities--twice a week on isometric maximal force (ISOmax) and force-time curve (force produced in 500 milliseconds, F0-500) and dynamic 1 repetition maximum (1RM) strength of the leg extensors, 10-m walking time (10WALK) and dynamic balance test (DYN.D) were investigated in 26 middle-aged (MI; 52.8 +/- 2.4 years) and 22 older women (O; 63.8 +/- 3.8 years). 1RM, ISOmax, and F0-500 increased significantly in MI by 28 +/- 10%, 20 +/- 19%, 31 +/- 34%, and in O by 27 +/- 8%, 20 +/- 16%, 18 +/- 45%, respectively. 10WALK (MI and O, p < 0.001) shortened and DYN.D improved (MI and O, p < 0.001). The present strength-training protocol led to large increases in maximal and explosive strength characteristics of leg extensors and in walking speed, as well to an improvement in the present dynamic balance test performance in both age groups. Although training-induced increase in explosive strength is an important factor for aging women, there are other factors that contribute to improvements in dynamic balance capacity. This study indicates that total body heavy resistance training, including explosive dynamic training, may be applied in rehabilitation or preventive exercise protocols in aging women to improve dynamic balance capabilities.

  11. Handgrip strength predicts functional decline at discharge in hospitalized male elderly: a hospital cohort study.

    PubMed

    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 intervene

  12. 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

  13. Effects of functional movement strength training on strength, muscle size, kinematics, and motor function in cerebral palsy: a 3-month follow-up.

    PubMed

    Lee, Jung Ah; You, Joshua H; Kim, Dong A; Lee, Min Jin; Hwang, Pil Woo; Lee, Nam Gi; Park, Jeong Joon; Lee, Dong Ryul; Kim, Hyun-Kyung

    2013-01-01

    We investigated the long-term effects of comprehensive hand repetitive intensive strengthening training (CHRIST) on strength, morphological muscle size, kinematics, and associated motor functional changes in children with cerebral palsy (CP). Ten children (5 boys, 5 girls; age range, 6-11 years, mean age, 8.6 years) participated in the study. The children were classified according to the Manual Ability Classification System: 5 were Level II, 2 were Level III, and 3 were Level IV. Quantitative biomechanical measurements were performed to determine muscle strength, muscle size, kinematics (normalized jerk score), and motor function using a dynamometer, ultrasound, Vicon motion analysis, and standardized clinical tests (Quality of Upper Extremity Skills Test, Jebsen-Taylor Hand Function Test, Functional Independence Measure, and Pediatric Motor Activity Log), respectively. Muscle strength, muscle size, kinematics, and motor function significantly improved after a 10-week intervention (3 times a week), and the long-term effects remained even at the 3-month follow-up. In conclusion, this is the first study highlighting the long-term efficacy of upper extremity strength training using the novel CHRIST system in children with CP, which will potentially open up new horizons for effective management in pediatric neurorehabilitation.

  14. 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 ...

  15. 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.

  16. 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

  17. Correlation between Limb Muscle Endurance, Strength, and Functional Capacity in People with Chronic Obstructive Pulmonary Disease

    PubMed Central

    Törnberg, Anna; Wadell, Karin

    2016-01-01

    Purpose: To examine the correlation between limb muscle function (endurance and strength) and functional capacity in upper limbs (ULs) and lower limbs (LLs) of people with chronic obstructive pulmonary disease (COPD). Method: This article describes a secondary analysis of data from a randomized controlled trial. A stationary dynamometer was used to measure isokinetic muscle strength and endurance; the 6-minute walk test, the 6-minute pegboard and ring test, and the unsupported UL exercise test were used to measure functional capacity. Results: Participants were 44 adults with COPD. Muscle strength and endurance in ULs and LLs demonstrated a moderate to strong correlation with functional capacity. When controlling for muscle strength, muscle endurance was moderately correlated with functional capacity in ULs and LLs, but when controlling for muscle endurance, there was no positive and significant correlation between muscle strength and functional capacity for the ULs or LLs. Conclusions: Functional capacity seems to be more closely related to limb muscle endurance than to limb muscle strength in people with COPD. PMID:27504047

  18. Flexural Strength of Functionally Graded Nanotube Reinforced Sandwich Spherical Panel

    NASA Astrophysics Data System (ADS)

    Mahapatra, Trupti R.; Mehar, Kulmani; Panda, Subrata K.; Dewangan, S.; Dash, Sushmita

    2017-02-01

    The flexural behaviour of the functionally graded sandwich spherical panel under uniform thermal environment has been investigated in the present work. The face sheets of the sandwich structure are made by the functionally graded carbon nanotube reinforced material and the core face is made by the isotropic and homogeneous material. The material properties of both the fiber and matrix are assumed to be temperature dependent. The sandwich panel model is developed in the framework of the first order shear deformation theory and the governing equation of motion is derived using the variational principle. For the discretization purpose a suitable shell element has been employed from the ANSYS library and the responses are computed using a parametric design language (APDL) coding. The performance and accuracy of the developed model has been established through the convergence and validation by comparing the obtained results with previously published results. Finally, the influence of different geometrical parameters and material properties on the flexural behaviour of the sandwich spherical panel in thermal environment has been investigated through various numerical illustrations and discussed in details.

  19. Strength training induced adaptations in neuromuscular function of premenopausal women with fibromyalgia: comparison with healthy women

    PubMed Central

    Hakkinen, A; Hakkinen, K; Hannonen, P; Alen, M

    2001-01-01

    OBJECTIVE—To investigate the effects of 21 weeks' progressive strength training on neuromuscular function and subjectively perceived symptoms in premenopausal women with fibromyalgia (FM).
METHODS—Twenty one women with FM were randomly assigned to experimental (FMT) or control (FMC) groups. Twelve healthy women served as training controls (HT). The FMT and HT groups carried out progressive strength training twice a week for 21 weeks. The major outcome measures were muscle strength and electromyographic (EMG) recordings. Secondary outcome measures were pain, sleep, fatigue, physical function capacity (Stanford Health Assessment Questionnaire), and mood (short version of Beck's depression index).
RESULTS—Female FMT subjects increased their maximal and explosive strength and EMG activity to the same extent as the HT group. Moreover, the progressive strength training showed immediate benefits on subjectively perceived fatigue, depression, and neck pain of training patients with FM.
CONCLUSIONS—The strength training data indicate comparable trainability of the neuromuscular system of women with FM and healthy women. Progressive strength training can safely be used in the treatment of FM to decrease the impact of the syndrome on the neuromuscular system, perceived symptoms, and functional capacity. These results confirm the opinion that FM syndrome has a central rather than a peripheral or muscular basis.

 PMID:11114277

  20. 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.

  1. 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.

  2. 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.

  3. The impact of rotator cuff pathology on isometric and isokinetic strength, function, and quality of life.

    PubMed

    MacDermid, Joy C; Ramos, Joanne; Drosdowech, Darren; Faber, Ken; Patterson, Stuart

    2004-01-01

    The purposes of this study were to determine the reliability of strength and self-reporting measures, the relationship of different strength measures to function, and the impact of rotator cuff pathology on patients' quality of life. Patients with nonoperated rotator cuff pathology (n = 36) and unaffected control subjects (n = 48) were assessed by use of the LIDO dynamometer to determine isometric and isokinetic (concentric and eccentric) strength of the shoulder rotators. The Shoulder Pain and Disability Index and Short Form-36 were self-reported by patients. Intraclass correlation coefficients (ICCs) were used to assess reliability, and Pearson correlations and multiple linear regression were used to determine the relationship between strength and function. The findings of this study include the following: (1) measures of self-reported physical disability had high reliability (ICC = 0.89); (2) the LIDO dynamometer reliably measured internal and external shoulder rotation strength in both concentric and isometric modes of testing (ICC = 0.78-0.94), whereas eccentric muscle actions had lower reliability; (3) all shoulder rotation strength measures were predictive of disability, with isometric external rotation strength being the most predictive (r = 0.56); and (4) the presence of rotator cuff pathology was highly predictive of impaired physical health quality of life (R(2) = 0.71, P < .001).

  4. Analysis of Reward Functions in Learning: Unconscious Information Processing: Noncognitive Determinants of Response Strength

    DTIC Science & Technology

    1984-05-01

    Research Note 84-76 ANALYSIS OF REWARD FUNCTIONS IN LEARNING: UNCONSCIOUS INFORMATION PROCESSING : Lf NONCOGNITIVE DETERMINANTS OF RESPONSE STRENGTH...Melvin H. Marx University of Missouri, Columbia David W. Bessemer , Contracting Officer’s Representative0 Submitted by Robert M. Sasmor, Director BASIC...REPORT & PERIOD COVERED ANALYSIS OF REWARD FUNCTIONS IN LEARNING: Final Report UNCONSCIOUS INFORMATION PROCESSING : NONCOGNITIVE Sept. 1978 - Sept. 15

  5. Muscle strength training to improve gait function in children with cerebral palsy.

    PubMed

    Eek, Meta Nyström; Tranberg, Roy; Zügner, Roland; Alkema, Kristina; Beckung, Eva

    2008-10-01

    The aim of the study was to investigate the influence of muscle strength training on gait outcomes in children with cerebral palsy. Sixteen children (two females, 14 males, Gross Motor Function Classification System levels I-II, mean age 12y 6mo, range 9y 4mo-15y 4mo) underwent muscle strength measurement using a handheld device, Gross Motor Function Measure (GMFM) assessment, three-dimensional gait analysis, joint range of motion assessment, and grading of spasticity before and after 8 weeks of training. All participants had a diagnosis of spastic diplegia and could walk without aids. Training consisted of exercises for lower extremity muscles with free weights, rubber bands, and body weight for resistance, three times a week. Values for muscle strength below normal were identified in all children; this was most pronounced at the ankle, followed by the hip muscles. After training, muscle strength and GMFM scores increased, velocity was unchanged, stride length increased, and cadence was reduced. There was an increase in hip extensor moment and power generated at push off. Eight weeks of muscle strength training can increase muscle strength and improve gait function.

  6. Adiposity, muscle mass, and muscle strength in relation to functional decline in older persons.

    PubMed

    Schaap, Laura A; Koster, Annemarie; Visser, Marjolein

    2013-01-01

    Aging is associated with changes in body composition and muscle strength. This review aimed to determine the relation between different body composition measures and muscle strength measures and functional decline in older men and women. By use of relevant databases (PubMed, Embase, and CINAHL) and keywords in a search from 1976 to April 2012, 50 articles were reviewed that met the inclusion criteria (written in English, a prospective, longitudinal design, involving older persons aged 65 years or more, and at least one of the measures that follow: body mass index (BMI), waist circumference, waist/hip ratio, midarm circumference, fat mass, muscle fat infiltration, muscle mass, or strength as independent variables and a measure of functional decline as outcome measure). Meta-analyses were performed and revealed that BMI ≥30 and low muscle strength were associated with functional decline (pooled odds ratio (OR) = 1.60, 95% confidence interval (CI): 1.43, 1.80, for BMI ≥30 and OR = 1.86, 95% CI: 1.32, 2.64, for muscle strength). Low muscle mass was not significantly associated with functional decline (pooled OR = 1.19, 95% CI: 0.98, 1.45). Future intervention research should focus on positive changes in body composition to prevent onset or worsening of functional decline in old age.

  7. Low-energy enhancement in the γ -ray strength functions of Ge,7473

    NASA Astrophysics Data System (ADS)

    Renstrøm, T.; Nyhus, H.-T.; Utsunomiya, H.; Schwengner, R.; Goriely, S.; Larsen, A. C.; Filipescu, D. M.; Gheorghe, I.; Bernstein, L. A.; Bleuel, D. L.; Glodariu, T.; Görgen, A.; Guttormsen, M.; Hagen, T. W.; Kheswa, B. V.; Lui, Y.-W.; Negi, D.; Ruud, I. E.; Shima, T.; Siem, S.; Takahisa, K.; Tesileanu, O.; Tornyi, T. G.; Tveten, G. M.; Wiedeking, M.

    2016-06-01

    The γ -ray strength functions and level densities of Ge,7473 have been extracted up to the neutron-separation energy Sn from particle-γ coincidence data using the Oslo method. Moreover, the γ -ray strength function of 74Ge above Sn has been determined from photoneutron measurements; hence these two experiments cover the range of Eγ≈1 -13 MeV for 74Ge. The obtained data show that both Ge,7473 display an increase in strength at low γ energies. The experimental γ -ray strength functions are compared with M 1 strength functions deduced from average B (M 1 ) values calculated within the shell model for a large number of transitions. The observed low-energy enhancements in Ge,7473 are adopted in the calculations of the Ge,7372(n ,γ ) cross sections, where there are no direct experimental data. Calculated reaction rates for more neutron-rich germanium isotopes are shown to be strongly dependent on the presence of the low-energy enhancement.

  8. [Peripheral muscle strength in stable COPD patients: correlation with respiratory function variables and quality of life].

    PubMed

    Toral Marín, J; Ortega, F; Cejudo, P; Elías, T; Sánchez, H; Montemayor, T

    1999-03-01

    The aim of this study was to assess peripheral muscle strength in patients with chronic obstructive pulmonary disease (COPD) using a simple test and to look for correlation with function variables, physiological strength variables and quality of life parameters. Twenty-three COPD patients with moderate to severe air-flow limitation (FEV1 = 39 +/- 12%) in stable phase but displaying inability to carry out daily tasks were enrolled. Peripheral muscle strength was assessed in all patients by measuring the maximum load in a single repetition of five simple upper and lower extremity exercises performed at a multi-gymnastics station. Results were compared to respiratory function variables (FVC, FEV1, FEV1/FVC and gasometry), to results of an exercise test on a cycle ergometer with monitoring of respiratory gases (VEmax, VO2max and Wmax), to endurance (minutes) to dyspnea (Mahler's scale) and to quality of life (Chronic Respiratory Disease Questionnaire-CRDQ). No relation between functional parameters and endurance in minutes was found. Minute ventilation (VE) proved to be significantly related to oxygen intake (VO) and maximum work in the stress test. Dyspnea on Mahler's scale was unrelated, but fatigue variables and emotional function variables on the CRDQ were related. We conclude that peripheral muscle strength is unrelated to level of flow limitation or exercise tolerance in COPD patients. Peripheral muscle strength is related, however, to maximum work load and some aspects of quality of life.

  9. Photon strength functions studied with the method of two-step cascades

    NASA Astrophysics Data System (ADS)

    Tomandl, I.; Honzátko, J.; Bečvář, F.; Krtička, M.; Cejnar, P.

    2000-07-01

    The method of two-step γ cascades, following the thermal neutron capture, has proved to be a promising tool for investigation of photon strength functions in the region of transition energies near 3 MeV. Using this method we studied behavior of photon strength functions in 108Ag, 116In, 125Te, 144,146Nd, 150Sm, 156,158Gd, 163Dy and 168Er. Besides the detailed information for individual nuclei a large amount of experimental data allows us to look for general trends in the mass region incorporating spherical, transitional and deformed nuclei. Despite continuing systematic study on other nuclei, some general conclusions could already be done.

  10. Nuclear level densities and gamma-ray strength functions of 145,149,151Nd isotopes

    NASA Astrophysics Data System (ADS)

    Ay, K. O.; Ozgur, M.; Algin, E.; Guttormsen, M.; Bello Garrote, F. L.; Crespo Campo, L.; Görgen, A.; Hagen, T. W.; Ingeberg, V. W.; Kheswa, B. V.; Klintefjord, M.; Larsen, A. C.; Midtbo, J. E.; Modamio, V.; Renstrom, T.; Rose, S. J.; Sahin, E.; Siem, S.; Tveten, G. M.; Zeiser, F.

    2016-10-01

    The nuclear level densities and gamma-ray strength functions are the key elements for Hauser-Feshbach statistical model calculations to predict reaction cross sections which have many applications including astrophysics. The nuclear level densities and y-ray strength functions have been determined for 145,149,151Nd isotopes below the neutron separation energies using the Oslo method with the 144,148,150Nd(d,p) reactions. The results from the first measurements as well as planned experiments at OCL will be presented.

  11. 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.

  12. Full pf shell study of A=47 and A=49 nuclei

    NASA Astrophysics Data System (ADS)

    Martínez-Pinedo, G.; Zuker, A. P.; Poves, A.; Caurier, E.

    1997-01-01

    Complete diagonalizations in the pf major shell lead to very good agreement with the experimental data (level schemes, transitions rates, and static moments) for the A=47 and A=49 isotopes of Ca, Sc, Ti, V, Cr, and Mn. Gamow-Teller and M1 strength functions are calculated. The necessary monopole modifications to the realistic interactions are shown to be critically tested by the spectroscopic factors for one particle transfer from 48Ca, reproduced in detail by the calculations. The collective behavior of 47Ti, and of the mirror pairs 47V-47Cr and 49Cr-49Mn is found to follow at low spins the particle plus rotor model. It is then analyzed in terms of the approximate quasi-SU(3) symmetry, for which some new results are given.

  13. 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..

  14. 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.

  15. Effects of strength and neuromuscular training on functional performance in athletes after partial medial meniscectomy

    PubMed Central

    Zhang, Xiaohui; Hu, Min; Lou, Zhen; Liao, Bagen

    2017-01-01

    The aims of this study were to determine an effective knee function rehabilitation program for athletes undergoing partial medial meniscectomy. Participants were randomly assigned to neuromuscular training (NT) or strength training (ST) group and subjected to functional assessments before surgery and again at 4, and 8 weeks post hoc. Functional knee assessment, such as Lysholm knee scoring, star excursion balance, and BTE PrimusRS isokinetic performance tests were evaluated in each group. All postoperational symptoms were significantly improved after 4 and 8 weeks of NT and ST. Both NT and ST programs showed effective knee function recovery seen as an increase in muscular strength and endurance. However, the NT program showed the most significant functional improvement of dynamic balance and coordination. PMID:28349042

  16. 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

  17. Mechanical sea-ice strength parameterized as a function of ice temperature

    NASA Astrophysics Data System (ADS)

    Hata, Yukie; Tremblay, Bruno

    2016-04-01

    Mechanical sea-ice strength is key for a better simulation of the timing of landlock ice onset and break-up in the Canadian Arctic Archipelago (CAA). We estimate the mechanical strength of sea ice in the CAA by analyzing the position record measured by the several buoys deployed in the CAA between 2008 and 2013, and wind data from the Canadian Meteorological Centre's Global Deterministic Prediction System (CMC_GDPS) REforecasts (CGRF). First, we calculate the total force acting on the ice using the wind data. Next, we estimate upper (lower) bounds on the sea-ice strength by identifying cases when the sea ice deforms (does not deform) under the action of a given total force. Results from this analysis show that the ice strength of landlock sea ice in the CAA is approximately 40 kN/m on the landfast ice onset (in ice growth season). Additionally, it becomes approximately 10 kN/m on the landfast ice break-up (in melting season). The ice strength decreases with ice temperature increase, which is in accord with results from Johnston [2006]. We also include this new parametrization of sea-ice strength as a function of ice temperature in a coupled slab ocean sea ice model. The results from the model with and without the new parametrization are compared with the buoy data from the International Arctic Buoy Program (IABP).

  18. Modeling the Residual Strength of a Fibrous Composite Using the Residual Daniels Function

    NASA Astrophysics Data System (ADS)

    Paramonov, Yu.; Cimanis, V.; Varickis, S.; Kleinhofs, M.

    2016-09-01

    The concept of a residual Daniels function (RDF) is introduced. Together with the concept of Daniels sequence, the RDF is used for estimating the residual (after some preliminary fatigue loading) static strength of a unidirectional fibrous composite (UFC) and its S-N curve on the bases of test data. Usually, the residual strength is analyzed on the basis of a known S-N curve. In our work, an inverse approach is used: the S-N curve is derived from an analysis of the residual strength. This approach gives a good qualitive description of the process of decreasing residual strength and explanes the existence of the fatigue limit. The estimates of parameters of the corresponding regression model can be interpreted as estimates of parameters of the local strength of components of the UFC. In order to approach the quantitative experimental estimates of the fatigue life, some ideas based on the mathematics of the semiMarkovian process are employed. Satisfactory results in processing experimental data on the fatigue life and residual strength of glass/epoxy laminates are obtained.

  19. 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

  20. 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…

  1. Level densities and γ-ray strength functions in Sn isotopes

    NASA Astrophysics Data System (ADS)

    Toft, H. K.; Larsen, A. C.; Agvaanluvsan, U.; Bürger, A.; Guttormsen, M.; Mitchell, G. E.; Nyhus, H. T.; Schiller, A.; Siem, S.; Syed, N. U. H.; Voinov, A.

    2010-06-01

    The nuclear level densities of Sn118,119 and the γ-ray strength functions of Sn116,118,119 below the neutron separation energy are extracted with the Oslo method using the (He3,αγ) and (He3,He3'γ) reactions. The level-density function of Sn119 displays steplike structures. The microcanonical entropies are deduced from the level densities, and the single neutron entropy of Sn119 is determined to be 1.7 ± 0.2 kB. Results from a combinatorial model support the interpretation that some of the low-energy steps in the level density function are caused by neutron pair breaking. An enhancement in all the γ-ray strength functions of Sn116-119, compared to standard models for radiative strength, is observed for the γ-ray energy region of ≃4-11 MeV. These small resonances all have a centroid energy of 8.0(1) MeV and an integrated strength corresponding to 1.7(9)% of the classical Thomas-Reiche-Kuhn sum rule. The Sn resonances may be due to electric dipole neutron skin oscillations or to an enhancement of the giant magnetic dipole resonance.

  2. 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.…

  3. 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

  4. THE EFFECTS OF VARIED TENSIONS OF KINESIOLOGY TAPING ON QUADRICEPS STRENGTH AND LOWER LIMB FUNCTION

    PubMed Central

    Franco, Yuri Rafael dos Santos; Nannini, Stella Bispo; Nakaoka, Gustavo Bezerra; dos Reis, Amir Curcio; Bryk, Flavio Fernandes

    2017-01-01

    Background Kinesiology Taping (KT) may promote changes in muscle strength and motor performance, topics of great interest in the sports-medicine sciences. These characteristics are purported to be associated with the tension generated by the KT on the skin. However, the most suitable tension for the attainment of these strength and performance effects has not yet been confirmed. Hypothesis/Purpose The purpose of the present study was to analyze the effects of different tensions of KT on the isometric contraction of the quadriceps and lower limb function of healthy individuals over a period of seven days. Study Design Blind, randomized, clinical trial. Methods One hundred and thirty healthy individuals were distributed into the following five groups: control (without KT); KT0 (KT without tension); KT50; KT75 and KT100 (approximately 50%, 75% and 100% tension applied to the tape, respectively). Assessments of isometric quadriceps strength were conducted using a hand held dynamometer. Lower limb function was assessed through Single Hop Test for Distance, with five measurement periods: baseline; immediately after KT application; three days after KT; five days after KT; and 72h after KT removal (follow-up). Results There were no statistically significant differences (p > 0.05) at any of the studied periods on participants’ quadriceps strength nor in the function of the lower dominant limb, based on comparisons between the control group and the experimental groups. Conclusion KT applied with different tensions did not produce modulations, in short or long-term, on quadriceps’ strength or lower limb function of healthy individuals. Therefore, this type of KT application, when seeking these objectives, should be reconsidered. Level of Evidence 1b PMID:28217419

  5. Strength and Functional Performance Recovery After Anterior Cruciate Ligament Reconstruction in Preadolescent Athletes

    PubMed Central

    Greenberg, Elliot M.; Greenberg, Eric T.; Ganley, Theodore J.; Lawrence, J. Todd R.

    2014-01-01

    Background: In the skeletally immature population, the incidence of anterior cruciate ligament (ACL) injuries and ACL reconstructions appears to be increasing. Differences in surgical techniques, physiology, and emotional maturity may alter the rehabilitation progression and impact the outcomes when compared with adults. Reports of objective strength recovery and performance-based outcome measures after pediatric ACL reconstruction (ACLR) are limited. Study Design: Retrospective case series. Level of Evidence: Level 4. Methods: All patients that underwent all-epiphyseal ACLR from January 2008 to August 2010 were identified. Isokinetic peak quadriceps/hamstring torque values and functional performance measures in unilateral hopping tasks were extracted and compared with the noninjured limb. A limb symmetry index (LSI) of ≥90% was considered satisfactory. Results: Complete data were available for 16 patients (mean age, 12.28 years; range, 8.51-14.88 years). By a mean 7 months (range, 3.02-12.56 years) postoperatively, only 9 of 16 (56%) were able to achieve a satisfactory LSI for quadriceps strength. For hamstring strength, 15 of 16 (94%) were able to achieve satisfactory LSI. By a mean of 12 months (range, 5.39-24.39 months) postoperatively, only 6 of 16 subjects (38%) were able to achieve satisfactory performance on all functional hop tests. At a mean 15.42 months (range, 8.58-24.39 months) postsurgery, only 4 of 16 (25%) subjects were able to achieve an LSI of ≥90% on all testing parameters. Conclusion: For some pediatric patients, significant strength and functional deficits may be present at greater than 1 year after ACLR. This population may require more prolonged rehabilitation programs to allow for adequate recovery of strength and function because of unique characteristics of normal growth and development. PMID:24982702

  6. Early-phase adaptations to intrahospital training in strength and functional mobility of children with leukemia.

    PubMed

    San Juan, Alejandro F; Fleck, Steven J; Chamorro-Viña, Carolina; Maté-Muñoz, José L; Moral, Susana; García-Castro, Javier; Ramírez, Manuel; Madero, Luis; Lucia, Alejandro

    2007-02-01

    Improvements in chemotherapy and radiotherapy have contributed to the high survival rate (approximately 70%) of childhood acute lymphoblastic leukemia (ALL). However, during treatment, lack of physical activity and treatment cause various short- to long-term side effects, such as muscle atrophy and physical deconditioning. The purpose of this study was to determine the effects of an intrahospital, short-duration (8 weeks) exercise training program on muscle strength and endurance and functional mobility of children with ALL. Seven children (4 boys and 3 girls; 4-7 years of age) who were in the maintenance phase of treatment for ALL were selected as subjects. Three training sessions of 90- to 120-minute duration were performed each week. Each session included 11 different strength exercises engaging the major muscle groups and aerobic training. Gains in strength and endurance were assessed with a 6 repetition maximum test for upper (seated bench press and seated lateral row) and lower extremities (leg press). Gains in functional mobility were assessed with the time up and go test (TUG) and the timed up and down stairs test (TUDS). Performance was significantly improved after the training program in all strength tests (p < 0.01 for seated bench press and p < 0.05 for both seated lateral row and seated leg press) and in the TUG test (p < 0.05). In summary, a period of time as short as 8 weeks is enough to produce clinically relevant early-phase adaptations in children receiving treatment against ALL (i.e., improved functional mobility and muscle strength). Although more research is needed in the area of exercise training and pediatric cancer, exercise sciences can play a beneficial role in assisting both oncologists in treating cancer and improving children's quality of life during and after treatment.

  7. 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.

  8. Respiratory and skeletal muscle strength in COPD: Impact on exercise capacity and lower extremity function

    PubMed Central

    Singer, Jonathan; Yelin, Edward H.; Katz, Patricia P.; Sanchez, Gabriela; Iribarren, Carlos; Eisner, Mark D.; Blanc, Paul D.

    2011-01-01

    PURPOSE We sought to quantify the impact of respiratory muscle and lower extremity strength on exercise capacity and lower extremity function in patients with chronic obstructive pulmonary disease (COPD). METHODS In 828 persons with COPD, we assessed the impact of reduced respiratory (maximum inspiratory pressure, MIP) and lower extremity muscle strength (quadriceps, QS) on exercise capacity (6 Minute Walk Distance, 6MWT) and lower extremity function (LEF, Short Physical Performance Battery). Multiple regression analyses taking into account key covariates, including lung function and smoking, tested the associations between muscle strength and exercise and functional capacity. RESULTS For each ½ standard deviation (0.5 SD) decrement in QS, men walked 18.3 meters less during 6MWT (95% CI −24.1 to −12.4); women 25.1 meters less (95% CI −31.1 to −12.4). For each 0.5 SD decrement in MIP, men walked 9.4 meters less during 6MWT (95% CI – 15.2 to −3.6); women 8.7 meters less (95% CI −14.1 to −3.4). For each 0.5 SD decrease in QS, men had a 1.32 higher odds (95% CI: 1.11 to 1.15) of poor LEF; women, 1.87 higher odds (95% CI: 1.54 to 2.27). Lower MIP (per 0.5 SD) was associated with increased odds of poor LEF in women (OR 1.18, 95% CI: 1.00 to 1.39), but not in men (OR 1.10, 95% CI: 0.93 to 1.31). CONCLUSION In COPD, reduced respiratory and lower extremity muscle strength are associated with decreased exercise and functional capacity. Muscle weakness is likely an important component of impairment and disability in patients with COPD. PMID:21240003

  9. A Novel Application of Eddy Current Braking for Functional Strength Training During Gait.

    PubMed

    Washabaugh, Edward P; Claflin, Edward S; Gillespie, R Brent; Krishnan, Chandramouli

    2016-09-01

    Functional strength training is becoming increasingly popular when rehabilitating individuals with neurological injury such as stroke or cerebral palsy. Typically, resistance during walking is provided using cable robots or weights that are secured to the distal shank of the subject. However, there exists no device that is wearable and capable of providing resistance across the joint, allowing over ground gait training. In this study, we created a lightweight and wearable device using eddy current braking to provide resistance to the knee. We then validated the device by having subjects wear it during a walking task through varying resistance levels. Electromyography and kinematics were collected to assess the biomechanical effects of the device on the wearer. We found that eddy current braking provided resistance levels suitable for functional strength training of leg muscles in a package that is both lightweight and wearable. Applying resistive forces at the knee joint during gait resulted in significant increases in muscle activation of many of the muscles tested. A brief period of training also resulted in significant aftereffects once the resistance was removed. These results support the feasibility of the device for functional strength training during gait. Future research is warranted to test the clinical potential of the device in an injured population.

  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. Particle-hole optical model and strength functions for high-energy giant resonances

    SciTech Connect

    Urin, M. H.

    2010-08-15

    A formulation of the particle-hole optical model is proposed for describing the contribution of the fragmentation effect to the formation of strength functions for high-energy giant resonances. The model is based on the Bethe-Goldstone equation for the energy-averaged particle-hole Green's function. In this equation, the particle-hole interaction that is induced by a virtual excitation of multiquasiparticle configurations and in which, upon averaging over energy, an imaginary part is contained is taken into account. An analogy with the single-quasiparticle optical model is discussed.

  12. 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

  13. Strength of Structural and Functional Frontostriatal Connectivity Predicts Self-Control in the Healthy Elderly

    PubMed Central

    Hänggi, Jürgen; Lohrey, Corinna; Drobetz, Reinhard; Baetschmann, Hansruedi; Forstmeier, Simon; Maercker, Andreas; Jäncke, Lutz

    2016-01-01

    Self-regulation refers to the successful use of executive functions and initiation of top-down processes to control one's thoughts, behavior, and emotions, and it is crucial to perform self-control. Self-control is needed to overcome impulses and can be assessed by delay of gratification (DoG) and delay discounting (DD) paradigms. In children/adolescents, good DoG/DD ability depends on the maturity of frontostriatal connectivity, and its decline in strength with advancing age might adversely affect self-control because prefrontal brain regions are more prone to normal age-related atrophy than other regions. Here, we aimed at highlighting the relationship between frontostriatal connectivity strength and DoG performance in advanced age. We recruited 40 healthy elderly individuals (mean age 74.0 ± 7.7 years) and assessed the DoG ability using the German version of the DoG test for adults in addition to the delay discounting (DD) paradigm. Based on diffusion-weighted and resting-state functional magnetic resonance imaging data, respectively, the structural and functional whole-brain connectome were reconstructed based on 90 different brain regions of interest in addition to a 12-node frontostriatal DoG-specific network and the resulting connectivity matrices were subjected to network-based statistics. The 90-nodes whole-brain connectome analyses revealed subnetworks significantly associated with DoG and DD with a preponderance of frontostriatal nodes involved suggesting a high specificity of the findings. Structural and functional connectivity strengths between the putamen, caudate nucleus, and nucleus accumbens on the one hand and orbitofrontal, dorsal, and ventral lateral prefrontal cortices on the other hand showed strong positive correlations with DoG and negative correlations with DD corrected for age, sex, intracranial volume, and head motion parameters. These associations cannot be explained by differences in impulsivity and executive functioning. This pattern

  14. 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

  15. 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.

  16. 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.

  17. Trunk strength and function using the multidirectional reach distance in individuals with non-traumatic spinal cord injury

    PubMed Central

    Gabison, Sharon; Verrier, Molly C.; Nadeau, Sylvie; Gagnon, Dany H.; Roy, Audrey; Flett, Heather M.

    2014-01-01

    Context Trunk control is essential to engage in activities of daily living. Measuring trunk strength and function in persons with spinal cord injury (SCI) is difficult. Trunk function has not been studied in non-traumatic SCI (NTSCI). Objectives To characterize changes in trunk strength and seated functional reach in individuals with NTSCI during inpatient rehabilitation. To determine if trunk strength and seated reach differ between walkers and wheelchair users. To explore relationships between trunk and hip strength and seated functional reach. Design Observational study. Setting Two SCI rehabilitation facilities. Participants 32 subacute inpatients (mean age 48.0 ± 15.4 years). Outcome measures Isometric strength of trunk and hip and function (Multidirectional Reach Test: MDRT) were assessed at admission and within 2 weeks of discharge. Analysis of variance was conducted for admission measures (MDRT, hip and trunk strength) between walkers and wheelchair users. Changes in MDRT, hip and trunk strength were evaluated using parametric and non-parametric statistics. The level of association between changes in values of MRDT and strength was also examined. Results Significant differences between walkers and wheelchair users were found for strength measures (P < 0.05) but not for MDRT. Left- and right-sided reaches increased in wheelchair users only (P < 0.05). Associations between changes in hip strength, trunk strength, and reach distance were found (R = 0.67–0.73). Conclusion In clinical settings, it is feasible and relevant to assess trunk, hip strength, and MRDT. Future studies require strategies to increase the number of participants assessed, in order to inform clinicians about relevant rehabilitation interventions. PMID:25229736

  18. Balance, gait, functionality and strength: comparison between elderly fallers and non-fallers

    PubMed Central

    Cebolla, Elaine C.; Rodacki, André L. F.; Bento, Paulo C. B.

    2015-01-01

    BACKGROUND: Accidental falls are a major health problem related to aging and affect one in every three elderly individuals over the age of sixty. OBJECTIVE: To evaluate and compare the muscle strength, gait kinematics parameters, and performance in functional tests between elderly subjects with and without a prior history of falls. In addition, the association between the history of falls and the variables that demonstrated differences between groups were tested. METHOD: 62 elderly subjects participated in the study and were allocated to the group with falls history (FG; n=20; 68.0±6.9 years old) or the group without falls history (CG; n=42; 65.5±4.1 years old). Maximal strength, gait kinematics parameters, and functional tests were tested. RESULTS: The FG showed lower muscle strength in the knee flexors (51.45±8.6 vs. 62.09±19 Kg), lower average toe clearance during the swing phase (0.04±0.006 vs. 0.043 ± 0.005 m), and lower performance in the "8-foot up-and-go" test (5.3±0.7 vs. 5.8±0.7 s) (p<0.05). There were no associations between any variables and falls, but the increased time in the "8-foot up-and-go" test may double the likelihood of a fall occurring. CONCLUSION: Fallers have reduced lower limb strength, gait alterations, the worst performance in the dynamic balance test, and an increased risk of falls. PMID:25993628

  19. Carboxyl functionalized carbon fibers with preserved tensile strength and electrochemical performance used as anodes of structural lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Feng, Mengjie; Wang, Shubin; Yu, Yalin; Feng, Qihang; Yang, Jiping; Zhang, Boming

    2017-01-01

    Carboxyl functionalized carbon fibers with preserved tensile strength and electrochemical properties were acquired through a simple chemical oxidation method, and the proposed underlying mechanism was verified. The surface of carboxyl functionalizing carbon fibers is necessary in acquiring functional groups on the surface of carbon fibers to further improve the thermal, electrical or mechanical properties of the fibers. Functionalization should preserve the tensile strength and electrochemical properties of carbon fibers, because the anodes of structural batteries need to have high strength and electrochemical properties. Functionalized with mixed H2SO4/HNO3 considerably reduced the tensile strength of carbon fibers. By contrast, the appearance of H3PO4 preserved the tensile strength of functionalized carbon fibers, reduced the dispersion level of tensile strength values, and effectively increased the concentration of functional acid groups on the surface of carbon fibers. The presence of phosphoric acid hindered the over-oxidation of turbostratic carbon, and consequently preserved the tensile strength of carbon fibers. The increased proportion of turbostratic carbon on the surface of carbon fibers concurrently enhanced the electrochemical properties of carbon fibers.

  20. Chronic Effects of Strength Training Vs. Hydro Aerobics on Functional and Cardiorespiratory Ability in Postmenopausal Women

    PubMed Central

    Novaes, Giovanni S.; Novaes, Jefferson S.; Vilaça-Alves, José; Silva, Gabriel Costa e; Garrido, Nuno D.; Furtado, Hélio; Reis, Victor M.

    2014-01-01

    The current study aimed to compare the effects of two exercise programs (Strength Training and Hydro Gymnastics) on the functional and cardiorespiratory abilities of Portuguese postmenopausal women. The study population consisted of 38 volunteers (age: 66.9 ± 6.1 years, body mass: 73.70 ± 10.38 kg, and body height: 1.55 ± 0.10 m). Subjects were randomly divided into two experimental groups and one control group: one group performed 24 weeks of strength training (GST; n = 14), another performed 24 weeks of hydro gymnastics (GH; n = 17) and a control group (CG; n = 7), where the subjects continued with their regular daily activities without involvement in any physical exercise program. Three assessments were performed: before the beginning of the program, 12 weeks after the start of the training program and 24 weeks after the start of the program. To assess the functional ability of the participants, several tests proposed by Jones and Rikli (2002) were performed. To evaluate the cardiorespiratory ability of the participants, a modified treadmill Bruce test was applied. Significant differences (p<0.05) were found between the two training methods in the tests, which primarily demanded muscular strength. Body mass and the body mass index showed significant differences during the three stages of assessment in the GST group (p<0.05). With respect to the values that represent the variables of cardiorespiratory ability, positive and significant changes were observed in the two experimental groups. It was concluded that both exercise programs promoted improvements in some indicators of the functional and cardiorespiratory abilities of Portuguese postmenopausal women. PMID:25713645

  1. 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

  2. Simultaneous Microscopic Description of Nuclear Level Density and Radiative Strength Function

    NASA Astrophysics Data System (ADS)

    Hung, N. Quang; Dang, N. Dinh; Huong, L. T. Quynh

    2017-01-01

    The nuclear level density (NLD) and radiative strength function (RSF) are simultaneously described within a microscopic approach, which takes into account the thermal effects of the exact pairing as well as the giant resonances within the phonon-damping model. The good agreement between the results of calculations and experimental data extracted by the Oslo group for 170,171,172Yb isotopes shows the importance of exact thermal pairing in the description of NLD at low and intermediate excitation energies. It also invalidates the assumption based on the Brink-Axel hypothesis in the description of the RSF.

  3. {gamma}-ray strength function method and its application to {sup 107}Pd

    SciTech Connect

    Utsunomiya, H.; Akimune, H.; Kondo, T.; Itoh, O.; Kamata, M.; Yamagata, T.; Goriely, S.; Daoutidis, I.; Harada, H.; Kitatani, F.; Goko, S.; Toyokawa, H.; Yamada, K.; Lui, Y.-W.; Arteaga, D. P.; Hilaire, S.; Koning, A. J.

    2010-12-15

    The {gamma}-ray strength function method is devised to indirectly determine radiative neutron capture cross sections for radioactive nuclei. This method is applied here to the {sup 107}Pd (T{sub 1/2}=6.5x10{sup 6} yr) case. Photoneutron cross sections were measured for {sup 105,106,108}Pd near neutron threshold with quasimonochromatic laser-Compton-scattering {gamma}-ray beams. These photoneutron cross sections as well as the reverse radiative neutron capture cross sections for {sup 104,105}Pd are used to provide constraints on the {sup 107}Pd(n,{gamma}){sup 108}Pd cross section.

  4. 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

  5. Muscular strength, functional performances and injury risk in professional and junior elite soccer players.

    PubMed

    Lehance, C; Binet, J; Bury, T; Croisier, J L

    2009-04-01

    Muscle strength and anaerobic power of the lower extremities are neuromuscular variables that influence performance in many sports activities, including soccer. Despite frequent contradictions in the literature, it may be assumed that muscle strength and balance play a key role in targeted acute muscle injuries. The purpose of the present study was to provide and compare pre-season muscular strength and power profiles in professional and junior elite soccer players throughout the developmental years of 15-21. One original aspect of our study was that isokinetic data were considered alongside the past history of injury in these players. Fifty-seven elite and junior elite male soccer players were assigned to three groups: PRO, n=19; U-21, n=20 and U-17, n=18. Players benefited from knee flexor and extensor isokinetic testing consisting of concentric and eccentric exercises. A context of lingering muscle disorder was defined using statistically selected cut-offs. Functional performance was evaluated throughout a squat jump and 10 m sprint. The PRO group ran faster and jumped higher than the U-17 group (P<0.05). No significant difference in isokinetic muscle strength performance was observed between the three groups when considering normalized body mass parameters. Individual isokinetic profiles enabled the identification of 32/57 (56%) subjects presenting lower limb muscular imbalance. Thirty-six out of 57 players were identified as having sustained a previous major lower limb injury. Of these 36 players, 23 still showed significant muscular imbalance (64%). New trends in rational training could focus more on the risk of imbalance and implement antagonist strengthening aimed at injury prevention. Such an intervention would benefit not only athletes recovering from injury, but also uninjured players. An interdisciplinary approach involving trainers, a physical coach, and medical staff would be of interest to consider in implementing a prevention programme.

  6. 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.

  7. Intrinsic muscle strength and voluntary activation of both lower limbs and functional performance after stroke.

    PubMed

    Horstman, Astrid M; Beltman, Marijke J; Gerrits, Karin H; Koppe, Peter; Janssen, Thomas W; Elich, Peter; de Haan, Arnold

    2008-07-01

    The objective of this study was to assess the nature of muscle weakness in both legs after stroke compared with able-bodied control individuals and to examine whether there is a relationship between the degree of muscle weakness and coactivation of knee extensors and flexors as well as voluntary activation capacity of knee extensors of both paretic and non-paretic legs and indices of functional performance. Maximal voluntary isometric torques of knee extensors (MVCe) and flexors (MVCf) were determined in 14 patients (bilaterally) and 12 able-bodied controls. Simultaneous measurements were made of torque and surface EMG from agonist and antagonist muscles. Coactivation was calculated. Supramaximal triplets were evoked with electrical stimulation to estimate maximal torque capacity and degree of voluntary activation of knee extensors. MVCs, activation and coactivation parameters were correlated to scores of seven functional performance tests. MVCe, MVCf and voluntary activation were lower in paretic lower limb (PL) compared with both non-paretic lower limb (NL) and control. Besides, all these parameters of NL were also lower than control. Electrically evoked torque capacity of knee extensors of PL was about 60% of both NL and control, which were not significantly different from each other. Strong significant correlations between strength, as well as voluntary activation, and functional performance were found. Coactivation did not correlate well with functional performance. Thus, whereas for NL activation failure can explain weakness, for PL both activation failure and reduced intrinsic torque capacity are responsible for the severe weakness. Activation capacity and muscle strength correlated strongly to functional performance, while coactivation did not.

  8. 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

  9. Obestatin is associated to muscle strength, functional capacity and cognitive status in old women.

    PubMed

    Mora, Mireia; Granada, María Luisa; Palomera, Elisabet; Serra-Prat, Mateu; Puig-Domingo, Manel

    2013-12-01

    Obestatin has been proposed to have anorexigenic and anti-ghrelin actions. The objective was to study obestatin concentrations in relation to handgrip strength, functional capacity and cognitive state in old women. The prospective study included 110 women (age, 76.93 ± 6.32) from the Mataró Ageing Study. Individuals were characterized by anthropometric variables, grip strength, Barthel and assessment of cognitive impairment [Mini Cognoscitive Examination (MCE) Spanish version], depressive status by the Geriatric Depression Scale (GDS) and frailty by the Fried criteria. Obestatin was measured by IRMA. Obestatin showed negative correlation to handgrip at basal time point (r = -0.220, p = 0.023) and at 2-year follow-up (r = -0.344, p = 0.002). Obestatin, divided into quartiles, showed a negative lineal association with handgrip: 11.03 ± 4.88 kg in first, 8.75 ± 4.08 kg in second, 8.11 ± 3.66 kg in third and 7.61 ± 4.08 kg in fourth quartile (p = 0.018). Higher obestatin levels were associated to increased weakness (categorized by handgrip of frailty criteria): 2.24 ± 0.42 ng/ml in weak vs. 1.87 ± 0.57 ng/ml in non-weak (p = 0.01). The decrease of either MCE or Barthel scores at 2-year follow-up was significantly higher in individuals in the fourth quartile of obestatin in comparison with individuals in the first quartile (p = 0.046 and p = 0.019, respectively). No association was found between obestatin and GDS score and neither with frailty as a condition. Obestatin is associated to low muscle strength, and impaired functional and cognitive capacity in old women participating in the Mataró Ageing Study.

  10. 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.

  11. 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

  12. Body Composition, Muscle Strength, and Physical Function of Patients with Bethlem Myopathy and Ullrich Congenital Muscular Dystrophy

    PubMed Central

    Miscione, Maria Teresa; Bruno, Francesca; Ripamonti, Claudio; Nervuti, Giuliana; Orsini, Riccardo; Faldini, Cesare; Pellegrini, Massimo; Cocchi, Daniela; Merlini, Luciano

    2013-01-01

    Objective. To determine the contributions of body mass, adiposity, and muscularity to physical function and muscle strength in adult patients with Bethlem myopathy (BM) and Ullrich congenital muscular dystrophy (UCMD). Materials and Methods. Evaluation involved one UCMD and 7 BM patients. Body composition was determined by body mass index (BMI) and dual-energy-X-ray-absorptiometry (DXA), muscle strength by dynamometry, physical function by the distance walked in 6 minutes (6MWD), forced vital capacity (FVC) by a spirometer. Results. Six participants were of normal weight and 2 overweight based on BMI; all were sarcopenic based on appendicular fat free mass index (AFFMI); and 7 were sarcopenic obese based on AFFMI and % fat mass. Average muscle strength was reduced below 50% of normal. The 6MWD was in BM patients 30% less than normal. FVC was reduced in 4 of the BM patients. Muscle strength had a good correlation with the physical function variables. Correlation between muscle strength and BMI was poor; it was very high with AFFMI. AFFMI was the best single explicator of muscle strength and physical function. Conclusion. Muscle mass determined by DXA explains most of the variability of the measures of muscle strength and physical function in patients with BM and UCMD. PMID:24163611

  13. 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.

  14. Monopole transition strength function of 12C in a three-α model

    NASA Astrophysics Data System (ADS)

    Ishikawa, Souichi

    2016-12-01

    The energy-level structure of the 12C nucleus at a few MeV above the three-α (3 α ) threshold is still unsatisfactorily known. For instance, most microscopic calculations predicted that there exist one 0+ state in this energy region besides the well-known Hoyle state, whereas some experimental and theoretical studies show the existence of two 0+ states. In this paper, I will take a 3 α -boson model for bound and continuum states in 12C and study a transition process from the 12C(01+) ground state to 3 α 0+ continuum states by the electric monopole (E 0 ) operator. The strength distribution of the process will be calculated as a function of 3 α energy using the Faddeev three-body theory. The Hamiltonian for the 3 α system consists of two- and three-α potentials, and some three-α potentials with different range parameters will be examined. Results of the strength function show a double-peaked bump at the low-energy region, which can be considered as two 0+ states. The peak at higher energy may originate from a 3 α resonant state. However, it is unlikely that the peak at the lower energy is related to a resonant state, which suggests that it may be due to a so-called "ghost anomaly." Distributions of decaying particles are also calculated.

  15. Utilization of carboxylic functional groups generated during purification of carbon nanotube fiber for its strength improvement

    NASA Astrophysics Data System (ADS)

    Im, Yong-O.; Lee, Sung-Hyun; Kim, Teawon; Park, Junbeom; Lee, Jaegeun; Lee, Kun-Hong

    2017-01-01

    One of the most promising method to produce carbon nanotube (CNT) fiber is directly spinning CNT fiber from CNT aerogel. Despite the advantage of this method in terms of productivity, the CNTs thus produced include impurities such as amorphous carbon and residual catalysts. To remove these unwanted materials, the CNT fiber is usually subjected to acid treatment. At the same time, however, the acid treatment damages the CNT wall, creating functional groups on it. In this work, specific tensile strength of CNT fibers was increased by introducing cross-links between the individual CNTs using carboxylic functional groups which were inevitably generated during the acid treatment of CNT fibers. The esterification of the carboxylic acid with 1,5-pentanediol as a linker resulted in cross-links in between the CNTs, thereby increasing the specific strength of the CNT fiber from 0.43 to 1.12 N/tex and Young's modulus from 30.70 to 47.57 N/tex. Supporting weak shear interactions of untreated CNT fiber by adding covalent bonding through the cross-linking reaction led to the improvement of mechanical properties of the CNT fiber. Elimination of impurities and narrowed interspacing between CNT bundles caused by acid treatment was also confirmed, which additionally contributed to enhancing the mechanical properties of CNT fiber.

  16. 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

  17. 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.

  18. DNA Cholesteric Pitch as a Function of Density and Ionic Strength

    PubMed Central

    Stanley, Christopher B.; Hong, Helen; Strey, Helmut H.

    2005-01-01

    The nature of chiral interactions among chiral biopolymers, such as DNA, protein α-helices, and rodlike virus particles, remains elusive. In particular, a satisfactory model connecting molecular chiral interactions and the pitch of the resulting chiral mesophases is lacking. We report the measurement of short-fragment (146-bp) DNA cholesteric spherulite pitch as a function of osmotic pressure, average DNA interaxial spacing, and salt concentration. We determined cholesteric pitch and interaxial spacing by polarizing optical microscopy and x-ray scattering, respectively, from which the twist-angle between DNA molecules can be calculated. Surprisingly, we found that decreasing ionic strength resulted in weaker chiral interactions between DNA chains, as evidenced by the decrease in the twist-angle, and consequent increase in the cholesteric pitch, for a fixed interaxial spacing. We propose that this behavior can be explained by increased smearing-out of the helical charge pattern along DNA as the Debye screening length is increased. PMID:16040751

  19. Level Densities, Thermodynamics and gamma -Ray Strength Functions in 163,164Dy

    NASA Astrophysics Data System (ADS)

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

    2009-03-01

    The nuclei 163,164Dy have been investigated by use of the Oslo method on data from the pick-up reaction {(3He,alpha )} and the inelastic scattering {(3He,3He')}, respectively. The experiment was conducted at the Oslo cyclotron laboratory (OCL). The gamma -decay and ejectiles were measured with the CACTUS multidetector array, which consists of 28 NaI gamma -detectores and 8 Delta E - E Si particle telescopes. Thermodynamic quantities have been extracted within the micro-canonical ensemble theory. The pygmy resonance found around 3 MeV in the gamma -ray strength function, also referred to as the scissors mode, was studied. The question whether the width of the pygmy resonance is reaction dependent is addressed.

  20. Gamma Strength Functions and Level Densities from 300 MeV Proton Scatttering at 0°

    NASA Astrophysics Data System (ADS)

    von Neumann-Cosel, Peter; Bassauer, Sergej; Martin, Dirk

    The gamma strength function (GSF) as well as total level densities (LDs) in 208Pb and 96Mo were extracted from high-resolution forward angle inelastic proton scattering data taken at RCNP, Osaka, Japan, and compared to experimental results obtained with the Oslo method in order to test the validity of the Brink-Axel (BA) hypothesis in the energy region of the pygmy dipole resonance. The case of 208Pb is inconclusive because of strong fluctuations of the GSF due to the small level density in a doubly closed-shell nucleus. In 96Mo the data are consistent with the BA hypothesis. The good agreement of LDs provides an independent confirmation of the approach underlying the decomposition of GSF and LDs in Oslo-type experiments.

  1. Strength function sum rules and the generalized Brink-Axel hypothesis

    NASA Astrophysics Data System (ADS)

    Johnson, Calvin W.

    2015-10-01

    Sum rules provide useful insights into transition strength functions and are often expressed as expectation values of an operator. I will show 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 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. Supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, under Award Number DE-FG02-96ER40985.

  2. 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.

  3. Resistance Training and Vibration Improve Muscle Strength and Functional Capacity in Female Patients with Multiple Sclerosis

    PubMed Central

    Eftekhari, Elham; Mostahfezian, Mina; Etemadifar, Masoud; Zafari, Ardeshir

    2012-01-01

    Purpose The purpose of this study was to evaluate the effect of an eight-week progressive resistance training and vibration program on strength and ambulatory function in multiple sclerosis (MS) patients. Methods Twenty-Four female MS patients with the following demographics: age 27-45 years, and expanded disability status scale (EDSS) 2-4, participated in this study. The subjects were randomly allocated to one of two groups. The exercise group (n = 12) trained according to a progressive program, mainly consisting of resistance training and vibration, three times a week for eight weeks and compared with subjects in the control group (n = 12) that received no intervention. Subjects completed one set of 5-12 reps at%50-70 maximal voluntary contraction (MVC). After 5-10 minutes rest, six postures on plate vibration were done. Isotonic MVC of knee extensors, abduction of the scapula and downward rotation of the scapular girdle muscle groups were predicted by using the Brzycki formula. Right leg balance (RLB), left leg balance (LLB), and walking speed (10-Meter Walk Test) were assessed before and after the training program. Descriptive statistics and Co-variance were used for analyzing data. Results After eight weeks of training the exercise group showed significant increase in MVC of Knee extensors (32.3%), Abduction of the scapula (24.7%) and Downward Rotation Scapular (39.1%) muscle groups, RLB (33.5%), LLB (9.5%), and decrease in 10-Meter Walk Test (10MWT) (9.3%), (P<0.05). Conclusions The results of this study indicated this type of training can cause improvements in muscle strength and functional capacity in patients with multiple sclerosis. PMID:23342227

  4. Low-energy modification of the γ strength function of the odd-even nucleus 115In

    NASA Astrophysics Data System (ADS)

    Versteegen, Maud; Denis-Petit, David; Méot, Vincent; Bonnet, Thomas; Comet, Maxime; Gobet, Franck; Hannachi, Fazia; Tarisien, Medhi; Morel, Pascal; Martini, Marco; Péru, Sophie

    2016-10-01

    Photoactivation yield measurements on 115In have been performed at the ELSA facility with Bremsstrahlung photon beams over a range of endpoint energies between 4.5 and 18 MeV. The measured photoexcitation yields of the Inm115 metastable state are compared with calculated yields using cross sections obtained with different models of the photon strength function. It is shown that additional photon strength with respect to the general Lorentzian model is needed at 8.1 MeV for the calculated yields to reproduce the data. The origin of this extra strength is unclear, because it is compatible with additional strength predicted in both E 1 and M 1 photon strength distributions by quasiparticle random-phase approximation calculations using the Gogny D1S force.

  5. Beta-decay properties of 25 Si and 26 P

    NASA Astrophysics Data System (ADS)

    Thomas, J.-C.; Achouri, L.; Äystö, J.; Béraud, R.; Blank, B.; Canchel, G.; Czajkowski, S.; Dendooven, P.; Ensallem, A.; Giovinazzo, J.; Guillet, N.; Honkanen, J.; Jokinen, A.; Laird, A.; Lewitowicz, M.; Longour, C.; Oliveira Santos, F.; Peräjärvi, K.; Stanoiu, M.

    2004-09-01

    The β-decay properties of the neutron-deficient nuclei 25Si and 26P have been investigated at the GANIL/LISE3 facility by means of charged-particle and γ-ray spectroscopy. The decay schemes obtained and the Gamow-Teller strength distributions are compared to shell-model calculations based on the USD interaction. B(GT) values derived from the absolute measurement of the β-decay branching ratios give rise to a quenching factor of the Gamow-Teller strength of 0.6. A precise half-life of 43.7 (6) ms was determined for 26P, the β-(2)p decay mode of which is described.

  6. 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

  7. Pygmy resonance and low-energy enhancement in the γ-ray strength functions of Pd isotopes

    NASA Astrophysics Data System (ADS)

    Eriksen, T. K.; Nyhus, H. T.; Guttormsen, M.; Görgen, A.; Larsen, A. C.; Renstrøm, T.; Ruud, I. E.; Siem, S.; Toft, H. K.; Tveten, G. M.; Wilson, J. N.

    2014-10-01

    Background: An unexpected enhancement in the γ-ray strength function, as compared to the low-energy tail of the giant dipole resonance (GDR), has been observed for Sc, Ti, V, Fe, and Mo isotopes for Eγ<4 MeV. This enhancement was not observed in subsequent analyses on Sn isotopes, but a pygmy dipole resonance (PDR) centered at Eγ≈8 MeV was however detected. The γ-ray strength functions measured for Cd isotopes exhibit both features over the range of isotopes, with the low-energy enhancement decreasing and PDR strength increasing as a function of neutron number. This suggests a transitional region for the onset of low-energy enhancement, and also that the PDR strength depends on the number of neutrons. Purpose: The γ-ray strength functions of Pd105-108 have been measured in order to further explore the proposed transitional region. Method: Experimental data were obtained at the Oslo Cyclotron Laboratory by using the charged particle reactions (He3,He3'γ) and (He3,αγ) on Pd106,108 target foils. Particle-γ coincidence measurements provided information on initial excitation energies and the corresponding γ-ray spectra, which were used to extract the level densities and γ-ray strength functions according to the Oslo method. Results: The γ-ray strength functions indicate a sudden increase in magnitude for Eγ>4 MeV, which is interpreted as a PDR centered at Eγ≈8 MeV. An enhanced γ-ray strength at low energies is also observed for Pd105, which is the lightest isotope measured in this work. Conclusions: A PDR is clearly identified in the γ-ray strength functions of Pd105-108, and a low-energy enhancement is observed for Pd105. Further, the results correspond and agree very well with the observations from the Cd isotopes, and support the suggested transitional region for the onset of low-energy enhancement with decreasing mass number. The neutron number dependency of the PDR strength is also evident.

  8. Knee muscle strength at varying angular velocities and associations with gross motor function in ambulatory children with cerebral palsy.

    PubMed

    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=17) or level II (n=16) according to Gross Motor Function Classification System (GMFCS) levels. All children underwent curl-up test and isokinetic tests of the knee extensor and flexor muscle. Children with CP underwent the gross motor function assessments, including the Gross Motor Function Measure (GMFM-66) and the gross motor subtests of Bruininks-Oseretsky Test of Motor Proficiency (BOTMP). The hamstring-quadriceps ratio (HQ ratio) was calculated as 100%×(isokinetic peak torque of hamstring (knee flexor)/isokinetic peak torque of quadriceps (knee extensor)). Children with GMFCS level II had lower BOTMP and GMFM-66 scores, curl-up scores, HQ ratio, and knee muscle strength, especially knee flexor, compared to those with GMFCS level I. The regression analysis showed that knee flexor torques at 60 and 90°/s are mainly related to balance (r(2)=0.167, p=0.011) and strength (r(2)=0.243, p=0.002) while knee flexor torques at 120°/s mainly contribute to running speed and agility (r(2)=0.372, p<0.001). These findings suggest that children with CP had knee strength deficits, especially knee flexor. Postural muscle (knee flexor) strength dominated gross motor function than antigravity muscle strength (knee extensor). The knee flexor strength at different angular velocities was associated with various gross motor tasks. The HQ ratio may be used as a potential biomarker to probe the therapeutic effectiveness for muscle strengthening in these children. These data may allow clinician for formulating effective muscle strengthening strategies for these children.

  9. Upper extremity function and its relation with hand sensation and upper extremity strength in patients with multiple sclerosis.

    PubMed

    Guclu-Gunduz, Arzu; Citaker, Seyit; Nazliel, Bijen; Irkec, Ceyla

    2012-01-01

    The purpose of this study was to investigate the relationships between the upper extremity functions, upper extremity strength and hand sensation in patients with Multiple Sclerosis (MS). Twenty-two patients with MS (mean age: 38.5 ± 8.31 years, median Expanded Disability Status Scale (EDSS): 2) and 10 healthy subjects were included. Upper extremity function was measured with the Nine-hole peg test, upper extremity strength (shoulder flexion-abduction, elbow flexion, pinch and grip) with hand-held dynamometer, hand grip dynamometer and manual pinch meter, threshold of light touch-pressure with Semmes-Weinstein monofilament, duration of vibration with 128-Hz frequency tuning fork, and distance of two-point discrimination with an aesthesiometer. Strength and functional level of the upper extremity, light touch-pressure, two-point discrimination, vibration sensations of the hand were lower in patients with MS compared with healthy controls (p < 0.05). Light touch-pressure sensation of thumb and index fingers, two-point discrimination of index finger and elbow flexion strength were found to be related with upper extremity function in patients with MS (p< 0.05). These results indicate that the hand sensation, upper extremity strength and function were affected in MS patients. Additionally upper extremity functions seem to be related with light touch-pressure and two-point discrimination sensations of the hand and elbow flexion strength. Upper extremity strengthening and sensorial training of the hand may contribute to the upper extremity function in patients with MS.

  10. 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.

  11. The influence of short-term strength training on health-related quality of life and executive cognitive function.

    PubMed

    Kimura, Ken; Obuchi, Shuichi; Arai, Takeshi; Nagasawa, Hiroshi; Shiba, Yoshitaka; Watanabe, Shuichiro; Kojima, Motonaga

    2010-01-01

    Strength training has been reported as a potentially useful exercise to improve psychological aspects in the elderly, but its effects remain controversial. This study investigated the effectiveness of strength training conducted twice a week for 12 weeks for improving health-related quality of life (HRQOL) and executive cognitive function. The study was a single-blind randomized controlled trial with assessments before and after intervention. HRQOL and executive function were assessed using the SF-36 Health Status Survey and a computerized neuro-cognitive assessment using task-switch reaction time trials, respectively. Subjects comprised 119 participants > or =65 years old, randomized to either strength training (n=65) or health education classes (controls, n=54). The strength training program was designed to strengthen the large muscle groups most important for functional activities and to improve balance. The effects of the intervention on the eight dimensions of the SF-36 in the control and training groups were analyzed. Only the mental health scale of the SF-36 was significantly improved for the training group compared with controls after 12 weeks. Task-switch reaction time and correct response rate remained unchanged. Short-term strength training might have modest positive effects on HRQOL, although this training period may not be sufficient to affect executive function in relatively healthy older people.

  12. Do muscle mass, muscle density, strength and physical function similarly influence risk of hospitalization in older adults?

    PubMed Central

    Cawthon, Peggy Mannen; Fox, Kathleen M.; Gandra, Shravanthi. R.; Delmonico, Matthew J.; Chiou, Chiun-Fang; Anthony, Mary S.; Sewall, Ase; Goodpaster, Bret; Satterfield, Suzanne; Cummings, Steven R.; Harris, Tamara B.

    2012-01-01

    Objectives To examine the association between strength, function, lean mass, muscle density and risk of hospitalization. Design Prospective cohort stud Setting Two U.S. clinical centers Participants Adults aged 70 – 80 years (N=3,011) from the Health, Aging and Body Composition Study. Measurements Measures included grip strength; knee extension strength; lean mass; walking speed; chair stand pace. Thigh computed tomography scans assessed muscle area and density (a proxy for muscle fat infiltration). Hospitalizations were confirmed by local review of medical records. Negative binomial regression models estimated incident rate ratios (IRRs) of hospitalization for race/sex specific quartiles of each muscle/function parameter separately. Multivariate models adjusted for age, body mass index, health status and coexisting medical conditions. Results During an average 4.7 years of follow-up, 1,678 (55.7%) participants experienced ≥1 hospitalization. Participants in the lowest quartile of muscle density were more likely to be subsequently hospitalized (multivariate IRR: 1.47, 95% CI: 1.24, 1.73) compared to the highest quartile. Similarly, participants with the weakest grip strength were at increased risk of hospitalization (MIRR: 1.52, 95% CI: 1.30, 1.78, Q1 vs. Q4). Comparable results were seen for knee strength, walking pace and chair stands pace. Lean mass and muscle area were not associated with risk of hospitalization. Conclusion Weak strength, poor function and low muscle density, but not muscle size or lean mass, were associated with an increased risk of hospitalization. Interventions to reduce the disease burden associated with sarcopenia should focus on increasing muscle strength and improving physical function rather than simply increasing lean mass. PMID:19682143

  13. 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

  14. 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.

  15. 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

  16. 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

  17. Determination of radiative neutron capture cross sections for unstable nuclei by the {gamma}-ray strength function method

    SciTech Connect

    Utsunomiya, H.; Goriely, S.

    2012-11-12

    An indirect method referred to as the {gamma}-ray strength function method has been devised to determine radiative neutron capture cross sections for unstable nuclei along the valley of {beta}-stability. This method is based on the {gamma}-ray strength function which interconnects radiative neutron capture and photoneutron emission within the statistical model. The method was applied to several unstable nuclei such as {sup 93,95}Zr, {sup 107}Pd, and 121,123Sn. This method offers a versatile application extended to unstable nuclei far from the stability when combined with Coulomb dissociation experiments at RIKEN-RIBF and GSI.

  18. 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}

  19. 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.

  20. Leg power in young women: relationship to body composition, strength, and function.

    PubMed

    Thomas, M; Fiatarone, M A; Fielding, R A

    1996-10-01

    The ability to generate high forces at high velocity (power) is an important component of physiologic reserve for both athletic performance and functional capacity. A comparison was made between different laboratory methods and field tests designed to evaluate leg power. Nineteen young healthy untrained women participated in this study. Maximum power during the double leg press (KP) occurred between 56-78% of the one repetition maximum (1-RM) and averaged (404 +/- 22 W). Rank-ordered correlation showed an association between KP and another measure of leg power measured on the leg extensor power rig (LR) when expressed per kg LBM (Rho = 0.565, P < 0.016). KP was also related to the 1-RM achieved on the double leg press (R2 = 0.584, P < 0.001). The KP test also correlated with the vertical jump (R2 = 0.538, P < 0.004) and maximal power output during the Wingate anaerobic power test (R2 = 0.299, P < 0.015). However, double leg press power was not related to time to run 40 yards (R2 = 0.020, P < 0.573) or maximal gait velocity (R2 = 0.136, P < 0.121). These results suggest that maximal power during the double leg press occurs at a higher percentage of maximal strength than previously reported. Double leg press power was related to vertical jump performance, validating this field test as a measure of leg muscle power in young women.

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

    NASA Astrophysics Data System (ADS)

    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.; Krtička, M.; Bečvář, F.

    2009-03-01

    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.

  2. 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.

  3. 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.

  4. 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.

  5. Quantitative muscle strength assessment in duchenne muscular dystrophy: longitudinal study and correlation with functional measures

    PubMed Central

    2012-01-01

    Background The aim of this study was to perform a longitudinal assessment using Quantitative Muscle Testing (QMT) in a cohort of ambulant boys affected by Duchenne muscular dystrophy (DMD) and to correlate the results of QMT with functional measures. This study is to date the most thorough long-term evaluation of QMT in a cohort of DMD patients correlated with other measures, such as the North Star Ambulatory Assessment (NSAA) or thee 6-min walk test (6MWT). Methods This is a single centre, prospective, non-randomised, study assessing QMT using the Kin Com® 125 machine in a study cohort of 28 ambulant DMD boys, aged 5 to 12 years. This cohort was assessed longitudinally over a 12 months period of time with 3 monthly assessments for QMT and with assessment of functional abilities, using the NSAA and the 6MWT at baseline and at 12 months only. QMT was also used in a control group of 13 healthy age-matched boys examined at baseline and at 12 months. Results There was an increase in QMT over 12 months in boys below the age of 7.5 years while in boys above the age of 7.5 years, QMT showed a significant decrease. All the average one-year changes were significantly different than those experienced by healthy controls. We also found a good correlation between quantitative tests and the other measures that was more obvious in the stronger children. Conclusion Our longitudinal data using QMT in a cohort of DMD patients suggest that this could be used as an additional tool to monitor changes, providing additional information on segmental strength. PMID:22974002

  6. 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

  7. Modified forelimb grip strength test detects aging-associated physiological decline in skeletal muscle function in male mice.

    PubMed

    Takeshita, Hikari; Yamamoto, Koichi; Nozato, Satoko; Inagaki, Tadakatsu; Tsuchimochi, Hirotsugu; Shirai, Mikiyasu; Yamamoto, Ryohei; Imaizumi, Yuki; Hongyo, Kazuhiro; Yokoyama, Serina; Takeda, Masao; Oguro, Ryosuke; Takami, Yoichi; Itoh, Norihisa; Takeya, Yasushi; Sugimoto, Ken; Fukada, So-Ichiro; Rakugi, Hiromi

    2017-02-08

    The conventional forelimb grip strength test is a widely used method to assess skeletal muscle function in rodents; in this study, we modified this method to improve its variability and consistency. The modified test had lower variability among trials and days than the conventional test in young C57BL6 mice, especially by improving the variabilities in male. The modified test was more sensitive than the conventional test to detect a difference in motor function between female and male mice, or between young and old male mice. When the modified test was performed on male mice during the aging process, reduction of grip strength manifested between 18 and 24 months of age at the group level and at the individual level. The modified test was similar to the conventional test in detecting skeletal muscle dysfunction in young male dystrophic mice. Thus, the modified forelimb grip strength test, with its improved validity and reliability may be an ideal substitute for the conventional method.

  8. Level Densities and Radiative Strength Functions in 56FE and 57FE

    SciTech Connect

    Tavukcu, Emel

    2002-12-10

    Understanding nuclear level densities and radiative strength functions is important for pure and applied nuclear physics. Recently, the Oslo Cyclotron Group has developed an experimental method to extract level densities and radiative strength functions simultaneously from the primary γ rays after a light-ion reaction. A primary γ-ray spectrum represents the γ-decay probability distribution. The Oslo method is based on the Axel-Brink hypothesis, according to which the primary γ-ray spectrum is proportional to the product of the level density at the final energy and the radiative strength function. The level density and the radiative strength function are fit to the experimental primary γ-ray spectra, and then normalized to known data. The method works well for heavy nuclei. The present measurements extend the Oslo method to the lighter mass nuclei 56Fe and 57Fe. The experimental level densities in 56Fe and 57Fe reveal step structure. This step structure is a signature for nucleon pair breaking. The predicted pairing gap parameter is in good agreement with the step corresponding to the first pair breaking. Thermodynamic quantities for 56Fe and 57Fe are derived within the microcanonical and canonical ensembles using the experimental level densities. Energy-temperature relations are considered using caloric curves and probability density functions. The differences between the thermodynamics of small and large systems are emphasized. The experimental heat capacities are compared with the recent theoretical calculations obtained in the Shell Model Monte Carlo method. Radiative strength functions in 56Fe and 57Fe have surprisingly high values at low γ-ray energies. This behavior has not been observed for heavy nuclei, but has been observed in other light- and medium-mass nuclei. The origin of this low γ-ray energy effect remains unknown.

  9. 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

  10. 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 =…

  11. Effects of aquatic exercise on muscle strength and functional performance of individuals with osteoarthritis: a systematic review.

    PubMed

    Mattos, Fernanda de; Leite, Neiva; Pitta, Arthur; Bento, Paulo Cesar Barauce

    Water-based exercises are recommended for people with osteoarthritis (OA), due to the beneficial effects on physical function, quality of life and symptom reduction. However, the effects on muscle strength are still controversial. The aim of this review was to assess and compare the effects of aquatic exercise programs on muscle strength and physical function in people with OA. A systematic search was performed at Pubmed, Scopus and Web of Science databases. Clinical trials with interventions involving aquatic exercises for individuals with OA were included. The methodological quality of the studies was evaluated using the PEDro scale. 296 studies were found and twelve were selected: six studies comparing water-based exercises with land-based exercise, and six comparing water-based exercise groups with the control group. Exercise programs included muscle strengthening, aerobic, balance, flexibility and stretching exercises. Duration of the program, weekly frequency, intensity and progression varied between studies. Beneficial effects of aquatic exercise were found on physical function. However, only two of five studies that assessed muscle strength observed positive effect of aquatic exercise. Although it is difficult to compare studies and establish guidelines for the standardized protocol formulation, it was observed that water-based exercises can be effective on improving physical function and increasing muscle strength, since they are well-structured, with exercise intensity and overload controlled.

  12. Effects of aquatic exercise on muscle strength and functional performance of individuals with osteoarthritis: a systematic review.

    PubMed

    Mattos, Fernanda de; Leite, Neiva; Pitta, Arthur; Bento, Paulo Cesar Barauce

    2016-09-28

    Water-based exercises are recommended for people with osteoarthritis (OA), due to the beneficial effects on physical function, quality of life and symptom reduction. However, the effects on muscle strength are still controversial. The aim of this review was to assess and compare the effects of Aquatic Exercise Programs on muscle strength and physical function in people with OA. A systematic search was performed at Pubmed, Scopus and Web of Science databases. Clinical trials with interventions involving Aquatic Exercises for individuals with OA were included. The methodological quality of the studies was evaluated using the PEDro scale. 296 studies were found and twelve were selected: six studies comparing water-based exercises with land-based exercise, and six comparing water-based exercise groups with the control group. Exercise programs included muscle strengthening, aerobic, balance, flexibility and stretching exercises. Duration of the program, weekly frequency, intensity and progression varied between studies. Beneficial effects of aquatic exercise were found on physical function. However, only two of five studies that assessed muscle strength observed positive effect of aquatic exercise. Although it is difficult to compare studies and establish guidelines for the standardized protocol formulation, it was observed that water-based exercises can be effective on improving physical function and increasing muscle strength, since they are well-structured, with exercise intensity and overload controlled.

  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. To what extent is mean EMG frequency during gait a reflection of functional muscle strength in children with cerebral palsy?

    PubMed

    Van Gestel, L; Wambacq, H; Aertbeliën, 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 of underlying muscle strength and/or the applied walking velocity. Surface EMG data of the lateral gastrocnemius (LGAS) and medial hamstrings (MEH) were collected during 3DGA. For each muscle, 20 CP children characterized by a weak and 20 characterized by a strong muscle (LGAS or MEH) were selected. A weak muscle was defined as a manual muscle testing score <3; a strong muscle was defined as a manual muscle testing score ≥4. Patient selection was based on the following inclusion criteria: (a) predominantly spastic type of CP (3-15 years old), (b) either (near) normal muscle strength or muscle weakness in at least one of the studied lower limb muscles, (c) no lower limb Botulinum Toxin-A treatment within 6 months prior to the 3DGA, (d) no history of lower limb surgery, and (e) high-quality noise-free EMG-data. For each muscle, twenty age-related typically developing (TD) children were included as controls. In both muscles a consistent pattern of increasing mean EMG frequency with decreasing muscle strength was observed. This was significant in the LGAS (TD versus weak CP). Walking velocity also had a significant effect on mean EMG frequency in the LGAS. Furthermore, based on R(2) and partial correlations, it could be concluded that both walking velocity and muscle strength have an impact on EMG, but the contribution of muscle strength was always higher. These findings underscore the potential of the mean EMG frequency recorded during 3DGA, for the evaluation of functional muscle strength in children with CP.

  15. Heavy resistance training increases muscle size, strength and physical function in elderly male COPD-patients--a pilot study.

    PubMed

    Kongsgaard, M; Backer, V; Jørgensen, K; Kjaer, M; Beyer, N

    2004-10-01

    This study investigated the effects of heavy resistance training in elderly males with chronic obstructive pulmonary disease (COPD). 18 Home-dwelling male patients (age range: 65-80 years), with a mean forced expiratory volume in the first second (FEV1) of 46 +/- 3.4% of predicted value, were recruited. Baseline and post-training assessments included: Cross-sectional area (CSA) of quadriceps assessed by MRI, isometric and isokinetic knee extension strength, isometric trunk strength, leg extension power, normal and maximal gait-speed on a 30 m track, stair climbing time, number of chair stands in 30 s, lung function (FEV1) and self-reported health. Subjects were randomized to a resistance training group (RE, n = 9) or a control group conducting breathing exercises (CON, n = 9). RE performed heavy progressive resistance training twice a week for 12 weeks. 6 RE and 7 CON completed the study. In RE the following improved (P < 0.05): Quadriceps CSA: 4%, isometric knee extension strength: 14%, isokinetic knee extension strength at 60 degrees /s.: 18%, leg extension power: 19%, maximal gait speed: 14%, stair climbing time: 17%, isometric trunk flexion: 5% and self-reported health. In CON no changes were found. In conclusion, 12 weeks of heavy resistance training twice a week resulted in significant improvements in muscle size, knee extension strength, leg extension power, functional performance and self-reported health in elderly male COPD patients.

  16. 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.

  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. Participation in daily life activities and its relationship to strength and functional measures in boys with Duchenne muscular dystrophy

    PubMed Central

    Bendixen, Roxanna M.; Lott, Donovan J.; Senesac, Claudia; Mathur, Sunita; Vandenborne, Krista

    2014-01-01

    Purpose While most studies of Duchenne muscular dystrophy (DMD) have focused on physical impairment, there is a need to explore how impairment impacts real life experiences in order to provide intervention strategies focused on participation. Objectives were: 1) to investigate the domains of participation in a sample of boys with Duchenne muscular dystrophy; 2) to compare a younger (<10 years) and older (≥10 years) group of boys with DMD with regard to participation; 3) to investigate strength and timed functional tests in a sample of boys with Duchenne muscular dystrophy; 4) to compare a younger (<10 years) and older (≥10 years) group of boys with DMD with regard to strength and timed functional tests; and 5) to explore associations between participation and strength and timed functional tests for our DMD cohorts. Methods This cross-sectional study included sixty boys with DMD (mean 9.3 years ±0.3). Boys completed strength testing, timed functional tests, the Children’s Assessment of Participation and Enjoyment and the ACTIVLIM. Independent samples t-tests were used to test for differences in all measures between our younger and older cohorts; Spearman’s (rank) correlation was used to assess relationships between participation and strength and time functional tests. Results Significant differences were found between our younger and older boys with DMD in the areas of recreational (p≤0.01), social (p≤0.001), and skill-based activities (p≤0.05), as well as with whom and where the activities were performed (p≤0.05 and 0.001, respectively). Older boys with DMD report lower levels of participation in these areas, as well as less engagement in activities with individuals other than family members and less participation outside of the home. Lower levels of strength and slower rates of functional performance correlate with participation in fewer physical activities for our younger cohort and fewer physical and social activities for our older cohort

  19. 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.

  20. 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.

  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. Functional and muscular adaptations in an experimental model for isometric strength training in mice.

    PubMed

    Krüger, Karsten; Gessner, Denise K; Seimetz, Michael; Banisch, Jasmin; Ringseis, Robert; Eder, Klaus; Weissmann, Norbert; Mooren, Frank C

    2013-01-01

    Exercise training induces muscular adaptations that are highly specific to the type of exercise. For a systematic study of the differentiated exercise adaptations on a molecular level mouse models have been used successfully. The aim of the current study was to develop a suitable mouse model of isometric strength exercise training characterized by specific adaptations known from strength training. C57BL/6 mice performed an isometric strength training (ST) for 10 weeks 5 days/week. Additionally, either a sedentary control group (CT) or a regular endurance training group (ET) groups were used as controls. Performance capacity was determined by maximum holding time (MHT) and treadmill spirometry, respectively. Furthermore, muscle fiber types and diameter, muscular concentration of phosphofructokinase 1 (PFK), succinate dehydrogenase (SDHa), and glucose transporter type 4 (GLUT4) were determined. In a further approach, the effect of ST on glucose intolerance was tested in diabetic mice. In mice of the ST group we observed an increase of MHT in isometric strength tests, a type II fiber hypertrophy, and an increased GLUT4 protein content in the membrane fraction. In contrast, in mice of the ET group an increase of VO(2max), a shift to oxidative muscle fiber type and an increase of oxidative enzyme content was measured. Furthermore strength training was effective in reducing glucose intolerance in mice fed a high fat diet. An effective murine strength training model was developed and evaluated, which revealed marked differences in adaptations known from endurance training. This approach seems also suitable to test for therapeutical effects of strength training.

  4. Reduced muscle strength and functional performance in men with prostate cancer undergoing androgen suppression: a comprehensive cross-sectional investigation.

    PubMed

    Galvão, D A; Taaffe, D R; Spry, N; Joseph, D; Turner, D; Newton, R U

    2009-01-01

    This study examined the effects of androgen suppression therapy (AST) on upper and lower body muscle strength and a range of direct measures of physical performance using a cross-sectional design with 118 men (48 men undertaking AST for prostate cancer and 70 healthy aged-matched controls) from a single tertiary center. Primary end points included muscle strength for the upper- and lower-body; functional performance--repeated chair rise, usual and fast 6-m walk, 6-m backwards walk and 400-m walk time; and dual-energy X-ray absorptiometry assessment--whole body, regional soft tissue composition and bone mineral density (BMD). Men on AST had significantly reduced muscle strength for the upper- and lower-body and impaired functional performance compared to controls (P<0.05). As expected, AST patients had significantly lower whole-body and hip BMD and higher percent of body fat than controls (P<0.05), and tended to have lower whole-body lean mass (-2.3 kg, P=0.077). Appendicular skeletal muscle was positively associated with upper-body (r=0.400-0.606, P<0.001) and lower-body (r=0.549-0.588, P<0.001) muscle strength, and strength was related to functional performance. Men undertaking AST were consistently impaired across a broad range of physical and functional musculoskeletal performance assessments compared with their age-matched normal controls. These findings are relevant for those patients considering AST for subclinical disease management, but whose physical reserve is marginal. Strategies to counter these adverse effects of AST need to be initiated so that independent living and quality of life can be maintained.

  5. 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.

  6. Arm function after stroke. An evaluation of grip strength as a measure of recovery and a prognostic indicator.

    PubMed Central

    Sunderland, A; Tinson, D; Bradley, L; Hewer, R L

    1989-01-01

    The value of strength of voluntary grip as an indicator of recovery of arm function was assessed by testing 38 recent stroke patients using a sensitive electronic dynamometer, and comparing the results with those from five other arm movement and function tests (Motricity Index, Motor Club Assessment, Nine Hole Peg Test, and Frenchay Arm Test). This procedure allowed measurement of grip in a large proportion of patients, and strength correlated highly with performance on the other tests. Measuring grip over a six month follow up period was a sensitive method of charting intrinsic neurological recovery. The presence of voluntary grip at one month indicates that there will be some functional recovery at six months. PMID:2592969

  7. Nuclear properties for astrophysical applications

    SciTech Connect

    Moeller, P.; Nix, J.R.; Kratz, K.L.

    1994-09-23

    We tabulate the ground-state odd-proton and odd-neutron spins, proton and neutron pairing gaps, binding energies, neuton separation energies, quantities related to {beta}-delayed one, two and three neutron emission probabilities, {beta}-decay Q values and half-lives with respect to Gamow-Teller decay, proton separation energies, and {alpha}-decay Q values and half-lives. The starting point of the calculations is a calculation of nuclear ground-states and (information based on the finite-range droplet model and the folded-Yukawa single-particle model published in a previous issue of ATOMIC DATA AND NUCLEAR DATA TABLES. The {beta}-delayed neutron-emission probabilities and Gamow-Teller {beta}-decay rates are obtained from a QRPA model that uses single-particle levels and wave-functions at the calculated nuclear ground-state shape as the starting point.

  8. Clustering of strength, physical function, muscle and adiposity characteristics and risk of disability in older adults

    PubMed Central

    Cawthon, Peggy M.; Fox, Kathleen M.; Gandra, Shravanthi. R.; Delmonico, Matthew J.; Chiou, Chiun-Fang; Anthony, Mary S.; Caserotti, Paolo; Kritchevsky, Stephen B.; Newman, Anne B.; Goodpaster, Bret H.; Satterfield, Suzanne; Cummings, Steven R.; Harris, Tamara B.

    2011-01-01

    Objectives Strength, physical performance, adiposity and lean mass may be independent risk factors for disability in older adults. The aim of this study was to empirically identify groupings of these interrelated measures and test how such groupings may relate to disability risk. Design Prospective Health, Aging and Body Composition Study (Health ABC) Setting Two US clinical centers Participants 1,263 women and 1,221 men Measurements Weight, strength (knee extension, grip); walking speed; chair stands; dual x-ray absorptiometry (fat and lean mass for total body, arm, and leg; percent fat); and thigh computed tomography scans (muscle area, muscle density). Analyses were stratified by sex. Factor analysis reduced these variables into a smaller number of components, and proportional hazards models assessed risk of major disability for the components identified. Results In both sexes, factor analysis reduced the 14 individual variables into three components that explained 76–77% of the data variance: Factor 1, an adiposity component, with strong loading by fat mass, weight and muscle density; Factor 2, a strength/lean body size component with strong loading by lean mass, weight and strength; Factor 3, a physical performance component with positive loading by walking speed and chair stands performance. Factor 1 (adiposity) and Factor 3 (performance), but not Factor 2 (strength/lean body size), were associated with disability over 6.1 (± 2.6 SD) years. Conclusion Adiposity and physical performance constructs, but not the strength/lean body size construct, were associated with disability risk, suggesting that adiposity and performance should be considered as risk factors for disability. PMID:21568948

  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. Validity of a power law approach to model tablet strength as a function of compaction pressure.

    PubMed

    Kloefer, Bastian; Henschel, Pascal; Kuentz, Martin

    2010-03-01

    Designing quality into dosage forms should not be only based on qualitative or purely heuristic relations. A knowledge space must be generated, in which at least some mechanistic understanding is included. This is of particular interest for critical dosage form parameters like the strength of tablets. In line with this consideration, the scope of the work is to explore the validity range of a theoretically derived power law for the tensile strength of tablets. Different grades of microcrystalline cellulose and lactose, as well as mixtures thereof, were used to compress model tablets. The power law was found to hold true in a low pressure range, which agreed with theoretical expectation. This low pressure range depended on the individual material characteristics, but as a rule of thumb, the tablets having a porosity of more than about 30% or being compressed below 100 MPa were generally well explained by the tensile strength relationship. Tablets at higher densities were less adequately described by the theory that is based on large-scale heterogeneity of the relevant contact points in the compact. Tablets close to the unity density therefore require other theoretical approaches. More research is needed to understand tablet strength in a wider range of compaction pressures.

  11. Strength Recovery Following Rhythmic or Sustained Exercise as a Function of Time.

    ERIC Educational Resources Information Center

    Kearney, Jay T.

    The relative rates of strength recovery subsequent to bouts of rhythmic or sustained isometric exercise were investigated. The 72 undergraduates who served as subjects were tested seven times within the framework of a repeated measures design. Each testing session involved two bouts of either rhythmic or sustained isometric exercise separated by a…

  12. 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.

  13. Functional performance, maximal strength, and power characteristics in isometric and dynamic actions of lower extremities in soccer players.

    PubMed

    Requena, Bernardo; González-Badillo, Juan José; de Villareal, Eduardo Saez Saez; Ereline, Jaan; García, Inmaculada; Gapeyeva, Helena; Pääsuke, Mati

    2009-08-01

    The purposes of the present study were to determine muscle strength and power output characteristics in a group of professional soccer players and to identify their relationships with 2 functional performance tests (vertical jumping height and 15-m sprint time). Maximal strength and power indices attained against different loads in barbell back squat exercise, isometric maximal force of the knee extensor and plantar flexor muscles, isokinetic peak torque of the knee extensors muscles, vertical jumping height in squat and counter-movement jumps, and 15-m sprint time tests were assessed in 21 semiprofessional soccer players (age 20 +/- 3.8 years). Correlation analyses were performed to examine the relationship between each of these measures. The main results of the present study were that (a) maximal power in concentric half-squat exercise was attained with a load of 60% of 1 repetition maximum, representing 112% of body weight; (b) the performance in the functional tests selected was significantly related with all the half-squat variables measured, especially with loads of 75-125% of body weight; and (c) low to nonsignificant correlations were found between functional tests performance and isometric and isokinetic muscle strength measures. It was concluded that in semiprofessional soccer players (a) isometric and isokinetic muscle strength assessed in an open kinetic chain were not movement-specific enough to predict performance during a more complex movement, such as jump or sprint and (b) concentric half-squat exercise was principally related with the functional tests selected when it was performed against external loading within the range of the load in case of which the maximal power output was attained.

  14. The contribution of leg press and knee extension strength and power to physical function in people with knee osteoarthritis: A cross-sectional study.

    PubMed

    Tevald, Michael A; Murray, Amanda M; Luc, Brittney; Lai, Kafai; Sohn, David; Pietrosimone, Brian

    2016-12-01

    The purposes of this study were to 1) determine the additional contributions of leg press and knee extensor power, over and above that of strength, to the performance of physical function tasks in people with knee osteoarthritis, and 2) compare the ability of bilateral leg press to unilateral knee extensor strength and power to predict functional task performance.

  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. Masked and unmasked priming effects as a function of semantic relatedness and associative strength.

    PubMed

    Sánchez-Casas, Rosa; Ferré, Pilar; Demestre, Josep; García-Chico, Teófilo; García-Albea, José E

    2012-11-01

    The study presented in this paper aimed to investigate the pattern of semantic priming effects, under masked and unmasked conditions, in the lexical decision task, manipulating type of semantic relation and associative strength. Three different kinds of word relations were examined in two experiments: only-semantically related words [e.g., codo (elbow)-rodilla (knee)] and semantic/associative related words with strong [e.g., mesa (table)-silla (chair) and weak association strength [e.g., sapo (toad)-rana (frog)]. In Experiment 1 a masked priming procedure was used with a prime duration of 56 ms, and in Experiment 2, the prime was presented unmasked for 150 ms. The results showed that there were masked priming effects with strong associates, but no evidence of these effects was found with weak associates or only-semantic related word pairs. When the prime was presented unmasked, the three types of relations produced significant priming effects and they were not influenced by association strength.

  17. Highlights from the Functional Single Nucleotide Polymorphisms Associated with Human Muscle Size and Strength or FAMuSS Study

    PubMed Central

    Pescatello, Linda S.; Devaney, Joseph M.; Hubal, Monica J.; Thompson, Paul D.; Hoffman, Eric P.

    2013-01-01

    The purpose of the Functional Single Nucleotide Polymorphisms Associated with Human Muscle Size and Strength study or FAMuSS was to identify genetic factors that dictated the response of health-related fitness phenotypes to resistance exercise training (RT). The phenotypes examined were baseline muscle strength and muscle, fat, and bone volume and their response to RT. FAMuSS participants were 1300 young (24 years), healthy men (42%) and women (58%) that were primarily of European-American descent. They were genotyped for ~500 polymorphisms and completed the Paffenbarger Physical Activity Questionnaire to assess energy expenditure and time spent in light, moderate, and vigorous intensity habitual physical activity and sitting. Subjects then performed a 12-week progressive, unilateral RT program of the nondominant arm with the dominant arm used as a comparison. Before and after RT, muscle strength was measured with the maximum voluntary contraction and one repetition maximum, while MRI measured muscle, fat, and bone volume. We will discuss the history of how FAMuSS originated, provide a brief overview of the FAMuSS methods, and summarize our major findings regarding genotype associations with muscle strength and size, body composition, cardiometabolic biomarkers, and physical activity. PMID:24455711

  18. Bulk flow strength of forsterite?enstatite composites as a function of forsterite content

    NASA Astrophysics Data System (ADS)

    Ji, Shaocheng; Wang, Zichao; Wirth, Richard

    2001-11-01

    Creep experiments have been conducted to investigate the effect of varying forsterite content ( VFo) on the bulk flow strength of dry forsterite-enstatite (Fo-En) aggregates in order to evaluate the applicability of existing theoretical models to two-phase rocks, as well as to understand the rheology of polyphase systems in general. The experiments were performed at temperatures of 1423-1593 K, stresses of 18-100 MPa, oxygen fugacities of 10 -14-10 -2.5 MPa and 0.1 MPa total pressure. The fine-grained (Fo: 10-17 μm; En: 14-31 μm) composites of various Fo volume fractions ( VFo=0, 0.2, 0.4, 0.5, 0.6, 0.8 and 1) were synthesized by isostatically hot-pressing in a gas-medium apparatus at 1523 and 350 MPa. Our experiments show that flow strength contrasts between Fo and En are in the range of 3-8 at the given experimental conditions, with Fo as the stronger phase. The measured stress exponent ( n) and activation energy ( Q) values of the Fo-En composites fall between those of the end-members. The n values show a nearly linear increase from 1.3 to 2.0, while the Q values display a non-linear increase from 472 to 584 kJ/mol with En volume fraction from 0 to 1.0. There is no clear dependence of creep rates on oxygen fugacity for the Fo-En composites. The mechanical data and TEM microstructural observations suggest no change in deformation mechanism of each phase when in the composites, compared to when in a single-phase aggregate, the En deformed mainly by dislocation creep while the Fo deformed by dislocation-accommodated diffusion creep for our grain sizes and experimental conditions. Comparisons between the measured composite strengths and various theoretical models indicate that none of the existing theoretical models can give a precise predication over the entire VFo range from 0 to 1. However, the theoretical models based on weak-phase supported structures (WPS) yield a good prediction for the flow strengths of the composites with VFo<0.4, while those based on

  19. Effects of functional and analytical strength training on upper-extremity activity after stroke: a randomized controlled trial

    PubMed Central

    Graef, Patrícia; Michaelsen, Stella M.; Dadalt, Maria L. R.; Rodrigues, Daiana A. M. S.; Pereira, Franciele; Pagnussat, Aline S.

    2016-01-01

    ABSTRACT Objective To investigate the effects of functional strengthening (using functional movements) and analytical strengthening (using repetitive movements) on level of activity and muscular strength gain in patients with chronic hemiparesis after stroke. Method A randomized, assessor-blinded trial was conducted in a therapist-supervised home rehabilitation program. Twenty-seven patients with chronic stroke were randomly allocated one of two groups: functional strengthening (FS) (n=13) and analytical strengthening (AS) (n=14). Each group received a five-week muscle strengthening protocol (30 minutes per day, three times per week) including functional movements or analytical movements, respectively. Pre-, post-, and ten-month follow-up outcomes included the Upper-Extremity Performance Test (primary outcome), Shoulder and Grip Strength, Active Shoulder Range of Motion (ROM), the Fugl-Meyer Assessment, and the Modified Ashworth Scale (MAS) (secondary outcomes). Results There was significant improvement in the Upper-Extremity Performance Test for the combined unilateral and bilateral task scores in the FS Group (mean difference 2.4; 95% CI=0.14 to 4.6) in the 10-month follow-up. No significant difference was observed between groups in the other outcomes (p>0.05). Conclusion A five-week home-based functional muscle strengthening induced positive results for the upper-extremity level of activity of patients with moderate impairment after chronic stroke. PMID:27683837

  20. Modified forelimb grip strength test detects aging-associated physiological decline in skeletal muscle function in male mice

    PubMed Central

    Takeshita, Hikari; Yamamoto, Koichi; Nozato, Satoko; Inagaki, Tadakatsu; Tsuchimochi, Hirotsugu; Shirai, Mikiyasu; Yamamoto, Ryohei; Imaizumi, Yuki; Hongyo, Kazuhiro; Yokoyama, Serina; Takeda, Masao; Oguro, Ryosuke; Takami, Yoichi; Itoh, Norihisa; Takeya, Yasushi; Sugimoto, Ken; Fukada, So-ichiro; Rakugi, Hiromi

    2017-01-01

    The conventional forelimb grip strength test is a widely used method to assess skeletal muscle function in rodents; in this study, we modified this method to improve its variability and consistency. The modified test had lower variability among trials and days than the conventional test in young C57BL6 mice, especially by improving the variabilities in male. The modified test was more sensitive than the conventional test to detect a difference in motor function between female and male mice, or between young and old male mice. When the modified test was performed on male mice during the aging process, reduction of grip strength manifested between 18 and 24 months of age at the group level and at the individual level. The modified test was similar to the conventional test in detecting skeletal muscle dysfunction in young male dystrophic mice. Thus, the modified forelimb grip strength test, with its improved validity and reliability may be an ideal substitute for the conventional method. PMID:28176863

  1. Interobserver agreement in the assessment of muscle strength and functional abilities in Guillain-Barré syndrome.

    PubMed

    Kleyweg, R P; van der Meché, F G; Schmitz, P I

    1991-11-01

    In studies of Guillain-Barré syndrome, functional deficit is usually assessed according to a functional scale consisting of several categories. The level of interobserver agreement in this scoring method is not known; furthermore, this method seems to be insensitive when applied to bedridden and artificially ventilated patients. We have developed an additional score (MRC-sumscore), reflecting muscle strength in general. Both scoring methods, tested in Guillain-Barré patients, have an almost perfect interobserver agreement. For the functional score kappa = 0.85, and for the MRC-sumscore r2 = 0.96. The MRC-sumscore is easily assessed and more sensitive than the functional score when patients are bedridden or artificially ventilated.

  2. Genetic perturbations that impair functional trait interactions lead to reduced bone strength and increased fragility in mice.

    PubMed

    Smith, Lauren M; Bigelow, Erin M R; Nolan, Bonnie T; Faillace, Meghan E; Nadeau, Joseph H; Jepsen, Karl J

    2014-10-01

    Functional adaptation may complicate the choice of phenotype used in genetic studies that seek to identify genes contributing to fracture susceptibility. Often, genetic variants affecting one trait are compensated by coordinated changes in other traits. Bone fracture is a prototypic example because mechanical function of long bones (stiffness and strength) depends on how the system coordinately adjusts the amount (cortical area) and quality (tissue-mineral density, TMD) of bone tissue to mechanically offset the natural variation in bone robustness (total area/length). We propose that efforts aimed at identifying genes regulating fracture resistance will benefit from better understanding how functional adaptation contributes to the genotype-phenotype relationship. We analyzed the femurs of C57BL/6J-Chr(A/J)/NaJ Chromosome Substitution Strains (CSSs) to systemically interrogate the mouse genome for chromosomes harboring genes that regulate mechanical function. These CSSs (CSS-i, i=the substituted chromosome) showed changes in mechanical function on the order of -26.6 to +11.5% relative to the B6 reference strain after adjusting for body size. Seven substitutions showed altered robustness, cortical area, or TMD, but no effect on mechanical function (CSS-4, 5, 8, 9, 17, 18, 19); six substitutions showed altered robustness, cortical area, or TMD, and reduced mechanical function (CSS-1, 2, 6, 10, 12, 15); and one substitution also showed reduced mechanical function but exhibited no significant changes in the three physical traits analyzed in this study (CSS-3). A key feature that distinguished CSSs that maintained function from those with reduced function was whether the system adjusted cortical area and TMD to the levels needed to compensate for the natural variation in bone robustness. These results provide a novel biomechanical mechanism linking genotype with phenotype, indicating that genes control function not only by regulating individual traits, but also by

  3. 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.

  4. Spin isospin responses in nuclei and their unified understanding with Landau Migdal parameters

    NASA Astrophysics Data System (ADS)

    Wakasa, Tomotsugu; RCNP E57, the; E59; E131; E149 Collaborations

    2005-01-01

    Both the Gamow-Teller (GT) and the pionic response functions are investigated in the same framework of the continuum random phase approximation with the π ρ + g' model interaction. The Landau-Migdal (LM) parameters, g'NN and g'NΔ, are estimated by comparing these calculations with recent experimental data. The peak of the GT resonance and the pionic response functions below the quasielastic scattering (QES) peak constrain g'NN, whereas the quenching of the GT total strength and the enhanced pionic strength around the QES peak provide information about g'NΔ. We obtain a common set of the LM parameters, g'NN = 0.6-0.7 and g'NΔ = 0.2-0.4, which reproduce the peak and quenching of the GT strengths as well as the enhancement of the pionic modes. The g'NΔ value is significantly smaller than g'NN, which means that the universality ansatz, g'NN = g'NΔ, should not be valid.

  5. 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

  6. 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.

  7. 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.

  8. Hydrogen bonding strength of diblock copolymers affects the self-assembled structures with octa-functionalized phenol POSS nanoparticles.

    PubMed

    Lu, Yi-Syuan; Yu, Chia-Yu; Lin, Yung-Chih; Kuo, Shiao-Wei

    2016-02-28

    In this study, the influence of the functional groups by the diblock copolymers of poly(styrene-b-4-vinylpyridine) (PS-b-P4VP), poly(styrene-b-2-vinylpyridine) (PS-b-P2VP), and poly(styrene-b-methyl methacrylate) (PS-b-PMMA) on their blends with octa-functionalized phenol polyhedral oligomeric silsesquioxane (OP-POSS) nanoparticles (NPs) was investigated. The relative hydrogen bonding strengths in these blends follow the order PS-b-P4VP/OP-POSS > PS-b-P2VP/OP-POSS > PS-b-PMMA/OP-POSS based on the Kwei equation from differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopic analyses. Small-angle X-ray scattering and transmission electron microscopic analyses show that the morphologies of the self-assembly structures are strongly dependent on the hydrogen bonding strength at relatively higher OP-POSS content. The PS-b-P4VP/OP-POSS hybrid complex system with the strongest hydrogen bonds shows the order-order transition from lamellae to cylinders and finally to body-centered cubic spheres upon increasing OP-POSS content. However, PS-b-P2VP/OP-POSS and PS-b-PMMA/OP-POSS hybrid complex systems, having relatively weaker hydrogen bonds, transformed from lamellae to cylinder structures at lower OP-POSS content (<50 wt%), but formed disordered structures at relatively high OP-POSS contents (>50 wt%).

  9. Is exercise used as medicine? Association of meeting strength training guidelines and functional limitations among older US adults

    PubMed Central

    Kraschnewski, Jennifer L.; Sciamanna, Christopher N.; Ciccolo, Joseph T.; Rovniak, Liza S.; Lehman, Erik B.; Candotti, Carolina; Ballentine, Noel H.

    2014-01-01

    OBJECTIVE To determine the association between meeting strength training (ST) guidelines (≥ 2 times per week) and the presence of functional limitations among older adults. METHODS This cross-sectional study used data from older adult participants (n=6,763) of the National Health Interview Survey conducted in 2011 in the United States. RESULTS Overall, 16.1% of older adults reported meeting ST guidelines. For each of nine functional limitations, those with the limitation were less likely to meet ST recommendations than those without the limitation. For example, 20.0% of those who reported no difficulty walking one-quarter mile met ST guidelines, versus only 10.1% of those who reported difficulty (p<.001). In sum, 21.7% of those with no limitations (33.7% of sample) met ST guidelines, versus only 15.9% of those reporting 1–4 limitations (38.5% of sample) and 9.8% of those reporting 5–9 limitations (27.8% of sample) (p<.001). CONCLUSION Strength training is uncommon among older adults and even less common among those who need it the most. The potential for ST to improve the public’s health is therefore substantial, as those who have the most to gain from ST participate the least. PMID:24878584

  10. 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.

  11. Meta-Analytic Approaches for Multistressor Dose-Response Function Development: Strengths, Limitations, and Case Studies.

    PubMed

    Levy, Jonathan I; Fabian, M Patricia; Peters, Junenette L

    2015-06-01

    For many policy analyses, including but not limited to cumulative risk assessments, it is important to characterize the individual and joint health effects of multiple stressors. With an increasing focus on psychosocial and other nonchemical stressors, this often includes epidemiological meta-analysis. Meta-analysis has limitations if epidemiological studies do not include all of the stressors of interest or do not provide multivariable outputs in a format necessary for risk assessment. Given these limitations, novel analytical methods are often needed to synthesize the published literature or to build upon available evidence. In this article, we discuss three recent case studies that highlight the strengths and limitations of meta-analytic approaches and other research synthesis techniques for human health risk assessment applications. First, a literature-based meta-analysis within a risk assessment context informed the design of a new epidemiological investigation of the differential toxicity of fine particulate matter constituents. Second, a literature synthesis for an effects-based cumulative risk assessment of hypertension risk factors led to a decision to develop new epidemiological associations using structural equation modeling. Third, discrete event simulation modeling was used to simulate the impact of changes in the built environment on environmental exposures and associated asthma outcomes, linking literature meta-analyses for key associations with a simulation model to synthesize all of the model components. These case studies emphasize the importance of conducting epidemiology with a risk assessment application in mind, the need for interdisciplinary collaboration, and the value of advanced analytical methods to synthesize epidemiological and other evidence for risk assessment applications.

  12. 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.

  13. Unified analysis of spin isospin responses of nuclei

    NASA Astrophysics Data System (ADS)

    Wakasa, T.; Ichimura, M.; Sakai, H.

    2005-12-01

    We investigate the Gamow-Teller (GT) response functions at a momentum transfer of q=0fm-1 and the pionic response functions for quasielastic scattering (QES) at q≈1.7fm-1 using the continuum random phase approximation with the π+ρ+g' model interaction. The Landau-Migdal (LM) parameters, g'NN and g'NΔ, are estimated by comparing the calculations with recent experimental data. The peak of the GT resonance and the pionic response functions below the QES peak constrain g'NN, whereas the quenching of the GT total strength and the enhanced pionic strength around the QES peak provide information about g'NΔ. We obtained g'NN=0.6±0.1 and g'NΔ=0.35±0.16 at q=0fm-1 and g'NN=0.7±0.1 and g'NΔ=0.3±0.1 at q≈1.7fm-1. These results indicate that the q dependence of the LM parameters is weak.

  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. Investigaton of the beta strength function at high energy: gamma-ray spectroscopy of the decay of 5. 3-s /sup 84/As to /sup 84/Se

    SciTech Connect

    Henry, E.A; Lien, O.G. III; Meyer, R.A.

    1981-06-01

    The beta strength function up to approximately 8.6 MeV for the system /sup 84/As(..beta../sup -/)/sup 84/Se was investigated. It was found that it is not possible to satisfactorily describe S/sub ..beta../ by a statistical model. From the /sup 84/As decay scheme an experimental beta strength function was deduced. Additional information on the beta transition intensity is obtained from the gross coincidence spectra of individual gamma rays. In total these data suggest that the experimental beta strength function above 6.8 MeV is significantly lower than that calculated using a statistical model. Features in the gross coincidence spectra also suggest that a significant bump appears in the experimental beta strength function at approximately 6.5 MeV.

  17. 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.

  18. [Muscle mass, muscle strength, and other functionality components in institutionalized older adults from Gran Caracas-Venezuela].

    PubMed

    Barbosa Murillo, J A P; Rodríguez, N G; Hernández H de Valera, Y M; Hernández, R A; Herrera, H A

    2007-01-01

    The present study has as objective to describe behavior of the different components of functionality and muscular mass, in institutionalized older people. Because levels of muscular mass have been associated with reduced levels of force, activity, functionality, depression of the immune function and increase of the morbidity and mortality risk. Were evaluated 152 elderly people older than 60 years old, men and women, of 14 geriatric centers of the Gran Caracas. Anthropometrical variable was measured to value the muscular mass and the body mass index. It was evaluated: hand isometric force, walking time 4.88 m and getting up of a seat. Descriptive statistic was carried out for all the variables, t of Student, Anova and Scheffé. It was observed that 80 years older elderly as well as, women present higher levels of disability, performed motor activities (to walk and to get up of a seat and a impair in physical conditions (lean mass and muscular strength) that interfere with functional status.

  19. Long-term strength training for community-dwelling people over 75: impact on muscle function, functional ability and life style.

    PubMed

    Capodaglio, Paolo; Capodaglio Edda, Maria; Facioli, Marco; Saibene, Francesco

    2007-07-01

    The objective was to determine the impact of a 1-year mixed strength-training programme on muscle function, functional ability, physical activity and life style. Twice-a-week hospital-based exercise classes and a once-a-week home session were conducted. Nineteen healthy community-dwelling training (T) men (76.6 +/- 3.1 years), 19 women (77.5 +/- 4.0 years) and 20 matched controls (C) participated in this study. Training was given with a two multi-gym machines for the lower limbs (Sitting calf and Leg press, TECHNOGYM, Italy) at 60% of the repetition maximum (1 RM) and at home it was with elastic bands. The following were the measurements made: muscle function-maximum isometric strength of the knee extensors (KE) and ankle plantar flexors (PF) measured with a Cybex Norm dynamometer, leg extensor power (LEP) with the Nottingham Power Rig; functional abilities-functional reach, chair rise, bed rise, 6-min walking test, stair climbing, get up and go, one-leg standing; physical activity-aerobic activities over 3 MET intensity (AA3), intensity classes; life-style-mean daily energy expenditure (MDEE). Significant gains in muscle function and functional abilities in both training females and males were observed, but females improved significantly more than males. Males (T + C) showed higher AA3 times than females (T + C) (P = 0.02), with females significantly more involved in light-intensity activities. We observed a 60% increase (t = 2.45) in AA3 time in T, but no increase in C. Trained males increased Class 2 physical activity time by 146% (t = 2.82) and trained females by 16% (t = 2.23). MDEE increased by 10% (t=2.62) in trained males. Our long-term mixed programme can improve muscle function and functional abilities in elderly females and functional abilities in males. It can positively affect the amount of habitual physical activity and the life-style of males and females over 75.

  20. The Effects of a Short-Term Novel Aquatic Exercise Program on Functional Strength and Performance of Older Adults.

    PubMed

    Kieffer, H Scott; Lehman, Marie Attanasi; Veacock, Danielle; Korkuch, Larua

    The purpose of this study was to determine the effects of a short-term novel multidimensional aquatic exercise program on functional abilities of healthy older adults. Twenty-six men and women (mean age 76.33 ± 5.55 years) were recruited and assigned to an aquatic- (n = 15) or land-based (n = 11) training group. The aquatic training group completed a multidimensional water exercise program that incorporated resistance training, functional exercise movements and rudimentary aquatic plyometric activities. The active control group participated in a supervised land-based fitness program. Each exercise intervention was conducted over an 8-week period (16 sessions of 30 - 40 minutes) with the training load progression adjusted equally between groups using the 6 - 20 Rating of Perceived Exertion Scale (RPE). Prior to and immediately following the intervention, both groups were evaluated with select components of the Senior Fitness Test. The 30-second chair stand, 30-second arm curl, and 8 foot up and go were selected as measures of strength and functional abilities. The results of an independent t-test indicated that the control and experimental groups were matched for functional abilities prior to the intervention. A 2 (group) × 2 (time) analysis of covariance (ANCOVA) with repeated measures revealed significant differences in the pre- to post-testing measures for the aquatic training program for the arm curl (p < 0.01) and the 8 foot up and go (p = 0.02). Analysis of the active control revealed no pre-post differences for any measure. Thus, a short-term aquatic exercise program with multidimensional intervention strategies will significantly enhance functional abilities in older adults when compared to a functionally matched active control group.

  1. 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

  2. Strength of metals under vibrations - dislocation-density-function dynamics simulations

    NASA Astrophysics Data System (ADS)

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

    2015-06-01

    It is well known that ultrasonic vibration can soften metals, and this phenomenon has been widely exploited in industrial applications concerning metal forming and bonding. Recent experiments show that the simultaneous application of oscillatory stresses from audible to ultrasonic frequency ranges can lead to not only softening but also significant dislocation annihilation and subgrain formation in metal samples from the nano- to macro-size range. These findings indicate that the existing understanding of ultrasound softening - that the vibrations either impose additional stress waves to augment the quasi-static applied load, or cause heating of the metal, whereas the metal's intrinsic deformation resistance or mechanism remains unaltered - is far from complete. To understand the softening and the associated enhanced subgrain formation and dislocation annihilation, a new simulator based on the dynamics of dislocation-density functions is employed. This new simulator considers the flux, production and annihilation, as well as the Taylor and elastic interactions between dislocation densities. Softening during vibrations as well as enhanced cell formation is predicted. The simulations reveal the main mechanism for subcell formation under oscillatory loadings to be the enhanced elimination of statistically stored dislocations (SSDs) by the oscillatory stress, leaving behind geometrically necessary dislocations with low Schmid factors which then form the subgrain walls. The oscillatory stress helps the depletion of the SSDs, because the chance for them to meet up and annihilate is increased with reversals of dislocation motions. This is the first simulation effort to successfully predict the cell formation phenomenon under vibratory loadings.

  3. Intermediate Nuclear Structure for 2v 2{beta} Decay of {sup 48}Ca Studied by (p, n) and (n, p) Reactions at 300 MeV

    SciTech Connect

    Sakai, H.; Yako, K.

    2009-08-26

    Angular distributions of the double differential cross sections for the {sup 48}Ca(p,n) and the {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) transition strengths. In the (n, p) spectrum beyond 8 MeV excitation energy extra B(GT{sup +}) strengths which are not predicted by the shell model calculation. This extra B(GT{sup +}) strengths significantly contribute to the nuclear matrix element of the 2v2{beta}-decay.

  4. 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.

  5. The analysis of mutant alleles of different strength reveals multiple functions of topoisomerase 2 in regulation of Drosophila chromosome structure.

    PubMed

    Mengoli, Valentina; Bucciarelli, Elisabetta; Lattao, Ramona; Piergentili, Roberto; Gatti, Maurizio; Bonaccorsi, Silvia

    2014-10-01

    Topoisomerase II is a major component of mitotic chromosomes but its role in the assembly and structural maintenance of chromosomes is rather controversial, as different chromosomal phenotypes have been observed in various organisms and in different studies on the same organism. In contrast to vertebrates that harbor two partially redundant Topo II isoforms, Drosophila and yeasts have a single Topo II enzyme. In addition, fly chromosomes, unlike those of yeast, are morphologically comparable to vertebrate chromosomes. Thus, Drosophila is a highly suitable system to address the role of Topo II in the assembly and structural maintenance of chromosomes. Here we show that modulation of Top2 function in living flies by means of mutant alleles of different strength and in vivo RNAi results in multiple cytological phenotypes. In weak Top2 mutants, meiotic chromosomes of males exhibit strong morphological abnormalities and dramatic segregation defects, while mitotic chromosomes of larval brain cells are not affected. In mutants of moderate strength, mitotic chromosome organization is normal, but anaphases display frequent chromatin bridges that result in chromosome breaks and rearrangements involving specific regions of the Y chromosome and 3L heterochromatin. Severe Top2 depletion resulted in many aneuploid and polyploid mitotic metaphases with poorly condensed heterochromatin and broken chromosomes. Finally, in the almost complete absence of Top2, mitosis in larval brains was virtually suppressed and in the rare mitotic figures observed chromosome morphology was disrupted. These results indicate that different residual levels of Top2 in mutant cells can result in different chromosomal phenotypes, and that the effect of a strong Top2 depletion can mask the effects of milder Top2 reductions. Thus, our results suggest that the previously observed discrepancies in the chromosomal phenotypes elicited by Topo II downregulation in vertebrates might depend on slight differences

  6. 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.

  7. Functional properties of protein from frozen mantle and fin of jumbo squid Dosidicus gigas in function of pH and ionic strength.

    PubMed

    Rocha-Estrada, J G; Córdova-Murueta, J H; García-Carreño, F L

    2010-10-01

    Functional properties of protein from mantle and fin of the jumbo squid Dosidicus gigas were explained based on microscopic muscle fiber and protein fractions profiles as observed in SDS-PAGE. Fin has higher content of connective tissue and complex fiber arrangement, and we observed higher hardness of fin gels as expected. Myosin heavy chain (MHC) was found in sarcoplasmic, myofibril and soluble-in-alkali fractions of mantle and only in sarcoplasmic and soluble-in-alkali fractions of fin. An additive effect of salt concentration and pH affected the solubility and foaming properties. Fin and mantle proteins yielded similar results in solubility tests, but significant differences occurred for specific pH and concentrations of salt. Foaming capacity was proportional to solubility; foam stability was also affected by pH and salt concentration. Hardness and fracture strength of fin gels were significantly higher than mantle gels; gels from proteins of both tissues reached the highest level in the folding test. Structural and molecular properties, such as MHC and paramyosin solubility, arrangement of muscle fibers and the content of connective tissue were useful to explain the differences observed in these protein properties. High-strength gels can be formed from squid mantle or fin muscle. Fin displayed similar or better properties than mantle in all tests.

  8. 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)

  9. IMPROVEMENTS IN KNEE EXTENSION STRENGTH ARE ASSOCIATED WITH IMPROVEMENTS IN SELF-REPORTED HIP FUNCTION FOLLOWING ARTHROSCOPY FOR FEMOROACETABULAR IMPINGEMENT SYNDROME

    PubMed Central

    Ellis, Thomas J.; Amesur, Ajit K.; Hewett, Timothy E.; Di Stasi, Stephanie

    2016-01-01

    Background Recovery of strength is critical for return to sport, and is a known predictor of functional outcomes in post-surgical orthopedic populations. Muscle weakness is a known impairment in patients with femoroacetabular impingement syndrome (FAIS) but whether improvements in muscle strength after arthroscopy are associated with improved hip function is unknown. Hypothesis/Purpose To examine the relationships between changes in hip and thigh muscle strength and self-reported function in athletes undergoing arthroscopy for FAIS. Study Design Single cohort descriptive and correlational study Methods Twenty-eight athletes underwent strength testing and completed the Hip Outcome Score Activities of Daily Living (HOS-ADL) and Sports (HOS-S) subscales prior to and six months after surgery. Isokinetic knee extension and flexion strength were measured using a Biodex dynamometer at 60 °/s and 300 °/s. Isometric hip abduction strength was measured using a custom dynamometer. Changes in strength, limb symmetry, and HOS scores were assessed using paired t-tests. Spearman's rank correlations were used to examine relationships between change in involved limb strength and change in HOS scores. Results Subjects were tested an average of 32 days before and 178 days after surgery. HOS-ADL and HOS-S subscales improved by a mean of 19.0 ± 21.1 and 23.8 ± 31.9, respectively, over time (p < 0.001). Hip abduction strength did not increase over time in either limb (p ≥ 0.27). Involved limb knee flexion and extension strength did not increase significantly over time (p-values: 0.10-0.48) with the exception of knee extension at 300 °/s (p = 0.04). Uninvolved limb knee extension strength at both velocities and knee flexion strength at 60 °/s improved significantly over time (p < 0.012). Increases in knee extension strength (60 °/s) of the involved limb were significantly correlated with improvements on the HOS-ADL (r = 0.431; 0 = 0

  10. Effect of floorball training on blood lipids, body composition, muscle strength, and functional capacity of elderly men.

    PubMed

    Vorup, J; Pedersen, M T; Melcher, P S; Dreier, R; Bangsbo, J

    2016-08-03

    Floorball training consists of intense repeated exercise and may offer a motivating and social stimulating team activity in elderly individuals. However, the effect of floorball training in elderly adults on physiological adaptations important for health is not known. Thus, this study examined the effect of floorball training on blood lipids, muscle strength, body composition, and functional capacity of men aged 65-76 years. Thirty-nine recreational active men were randomized into a floorball group (FG; n = 22) or petanque group (PG; n = 17), in which training was performed 1 h twice a week for 12 weeks. In FG and PG, average heart rate (HR) during training was 80% and 57%, respectively, of maximal HR. In FG, plasma low-density lipoprotein (LDL) cholesterol and triglycerides were 11% and 8% lower (P < 0.05), respectively. Insulin resistance determined by homeostatic model assessment (HOMA-IR) was reduced (P < 0.05) by 18%. HR during submaximal cycling was 5% lower (P < 0.05), and maximal voluntary contraction force was 8% higher (P < 0.05). Total and visceral fat content was lowered (P < 0.05) by 5% and 14%, respectively, HR at rest was 8% lower (P < 0.05) and performance in four different functional capacity tests were better (P < 0.05) after compared to before the training period. No changes were observed in PG. In conclusion, 12 weeks of floorball training resulted in a number of favorable effects important for health and functional capacity, suggesting that floorball training can be used as a health-promoting activity in elderly men.

  11. 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.

  12. Muon capture on deuteron and He3

    NASA Astrophysics Data System (ADS)

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

    2011-01-01

    The muon-capture reactions H2(μ-,νμ)nn and He3(μ-,νμ)H3 are studied with conventional or chiral realistic potentials and consistent weak currents. The initial and final A=2 and A=3 nuclear wave functions are obtained from the Argonne v18 or chiral next-to-next-to-next-to leading order (N3LO) two-nucleon potential, in combination with, respectively, the Urbana IX or chiral next-to-next-to leading order (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 (χEFT) framework. There is one parameter (either the N-to-Δ axial coupling constant in the meson-exchange model, or the strength of a contact term in the χEFT model) that is fixed by reproducing the Gamow-Teller matrix element in tritium β decay. The model dependence relative to the adopted interactions and currents (and cutoff sensitivity in the χEFT 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.

  13. 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.

  14. 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

  15. 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

  16. Shear deformation, ideal strength, and stacking fault formation of fcc metals: A density-functional study of Al and Cu

    NASA Astrophysics Data System (ADS)

    Jahnátek, Michal; Hafner, Jürgen; Krajčí, Marián

    2009-06-01

    Ab initio density-functional calculations have been used to study the response of two face-centered-cubic metals (Al and Cu) to shearing parallel to the close-packed (111) planes along two different directions, [112¯] and [1¯10] . Two different types of deformations—affine and alias—have been investigated. Under an affine shear deformation, all atoms are shifted parallel to the shearing direction by a distance proportional to their distance from the fixed basal plane. In the alias regime, only the top layer is displaced in the shearing direction. In both regimes, calculations have been performed with (pure shear) and without (simple shear) relaxation. For a pure alias shear, due to the interaction between the atoms, the displacement propagates through the sample; this is certainly the most realistic description of the shearing processes. In the pure alias regime, shear deformation, theoretical shear strength, and stacking fault formations may be described on a common footing. For small strains (in the elastic region), affine and alias shears lead to very similar results. Beyond the elastic limit, relaxation has a strong influence of the response on an applied shear strain. The elastic shear moduli are significantly larger for Cu than for Al, but a much higher shear strength is calculated for Al, although the shear strength is limited by the occurrence of a stacking fault instability before the stress maximum is reached. Under ⟨1¯10⟩ {111} shear the analysis of the atomistic deformation mechanism shows that in this case the formation of a stacking fault leads to a splitting of the (1)/(2)[1¯10] dislocation into two partial Shockley dislocations. Due to the repulsive interaction between the atoms in adjacent close-packed planes, the atoms in the top A layer move along (1)/(6)[2¯11] to a position directly above the B layer such that the stable intrinsic stacking fault configuration is the same for both slip systems. The analysis of the variation in the

  17. 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...

  18. Effect of strength training of ankle plantarflexors on selective voluntary motor control, gait parameters, and gross motor function of children with cerebral palsy.

    PubMed

    Jung, Jee Woon; Her, Jin Gang; Ko, Jooyeon

    2013-10-01

    [Purpose] The purpose of this study was to investigate the effect of ankle plantarflexor strength training on selective voluntary motor control, gait parameters, and gross motor function of children with cerebral palsy (CP), focusing on changes in the strength and muscle activity of the ankle plantarflexors. [Methods] Six children aged between 4 and 10 years with CP participated in a 6 week strengthening program. The subjects were evaluated before and after the intervention in terms of ankle plantarflexor strength, muscle activity, gait velocity, cadence, step length, and D (standing) and E (walking, running, and jumping) dimensions of the Gross Motor Function Measure (GMFM). The data were analyzed using the non-parametric Wilcoxon signed-rank test. [Results] The strength of the plantarflexors increased in the majority of subjects. Significant and clinically meaningful post-intervention improvements in subject's gait velocity, cadence, and step length were found. [Conclusion] The controlled ankle plantarflexor strengthening program may lead to improvements in strength and spatiotemporal gait parameters of children with CP.

  19. Translational recognition of the 5'-terminal 7-methylguanosine of globin messenger RNA as a function of ionic strength.

    PubMed

    Chu, L Y; Rhoads, R E

    1978-06-13

    The translation of rabbit globin mRNA in cell-free systems derived from either wheat germ or rabbit reticulocyte was studied in the presence of various analogues of the methylated 5' terminus (cap) as a function of ionic strength. Inhibition by these analogues was strongly enhanced by increasing concentrations of KCl, K(OAc), Na(OAc), or NH4(OAc). At appropriate concentrations of K(OAc), both cell-free systems were equally sensitive to inhibition by m7GTP. At 50 mM K(OAc), the reticulocyte system was not sensitive to m7GMP or m7GTP, but at higher concentrations up to 200 mM K(OAc), both nucleotides caused strong inhibition. The compound in m7G5'ppp5'Am was inhibitory at all concentrations of K(OAc) ranging from 50 to 200 mM, although more strongly so at the higher concentrations. Over the same range of nucleotide concentrations, the compounds GMP, GTP, and G5'ppp5'Am were not inhibitors. The mobility on sodium dodecyl sulfate-polyacrylamide electrophoresis of the translation product was that of globin at all K(OAc) concentrations in the presence of m7GTP. Globin mRNA from which the terminal m7GTP group had been removed by chemical treatment (periodate-cyclohexylamine-alkaline phosphatase) or enzymatic treatment (tobacco acid pyrophosphatase-alkaline phosphatase) was translated less efficiently than untreated globin mRNA at higher K(OAc) concentrations, but retained appreciable activity at low K(OAc) concentrations.

  20. Improvement of gait following functional electrical stimulation. I. Investigations on changes in voluntary strength and proprioceptive reflexes.

    PubMed

    Carnstam, B; Larsson, L E; Prevec, T S

    1977-01-01

    Patients with central spastic paresis and equipped with peroneal stimulators sometimes experience an improvement in their gait, even when the stimulator has been switched off. The object of the present investigation was to reach a better understanding of the mechanisms operating in such cases. 7 patients were investigated on repeated occasions. It was found that some of these patients got a clear increase in isometric strength of foot dorsiflexion following 10 min of peroneal stimulation. In other cases the increase was only slight. There was an inverse relation between the increase and the strength before stimulation. The increase of strength was due, at least partly, to an increased ability to activate the foot dorsiflectors, since there was a simultaneous increase in the EMG from the anterior tibial muscle. Evidence was also obtained suggesting that the increase in strength involved not only foot dorsiflexion but also plantarflexion of the foot end extension of the knee. Following peroneal stimulation there was also a decrease of the achilles reflex and in some cases possibly also the patellar reflex. There was an inverse relation between the decrease in the achilles reflex and its strength before stimulation. It is probable that the changes in voluntary strength and reflex activity reflect conditions which can be of importance in explaining the gait improvement which is sometimes observed in patients equippped with peroneal stimulators.

  1. Effects of strength training aided by electrical stimulation on wrist muscle characteristics and hand function of children with hemiplegic cerebral palsy.

    PubMed

    Vaz, Daniela Virgínia; Mancini, Marisa Cotta; da Fonseca, Sérgio Teixeira; Arantes, Nayara Flamini; Pinto, Tatiana Pessoa da Silva; de Araújo, Priscila Albuquerque

    2008-01-01

    Nine children with spastic hemiplegic cerebral palsy underwent 24 sessions of wrist muscles strengthening in the extended wrist range aided by electrostimulation. Isometric strength of flexors and extensors was registered in three wrist positions (30 degrees of flexion, neutral, and 30 degrees of extension) to infer on angle-torque curves. Passive stiffness of wrist flexors and wrist flexion angle during manual tasks and hand function were also documented. Significant strength gains were observed at 30 degrees of wrist extension for flexors (p= 0.029) and extensors (p= 0.024). No gains were observed at 30 degrees of flexion. The difference in extensor strength between the three test positions changed after intervention (p< 0.034), suggesting a shift in the angle-torque curve. No changes were observed in passive stiffness (p= 0.506), wrist angle (p< 0.586), or hand function (p= 0.525). Strength training in specific joint ranges may alter angle-torque relationships. For functional gains to be observed, however, a more aggressive intervention and contextualized task training would probably be needed.

  2. 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

  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. 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.

  5. Electron-capture Rates for pf-shell Nuclei in Stellar Environments and Nucleosynthesis

    NASA Astrophysics Data System (ADS)

    Suzuki, Toshio; Honma, Michio; Mori, Kanji; Famiano, Michael A.; Kajino, Toshitaka; Hidakai, Jun; Otsuka, Takaharu

    Gamow-Teller strengths in pf-shell nuclei obtained by a new shell-model Hamltonian, GXPF1J, are used to evaluate electron-capture rates in pf-shell nuclei at stellar environments. The nuclear weak rates with GXPF1J, which are generally smaller than previous evaluations for proton-rich nuclei, are applied to nucleosynthesis in type Ia supernova explosions. The updated rates are found to lead to less production of neutron-rich nuclei such as 58Ni and 54Cr, thus toward a solution of the problem of over-production of neutron-rich isotopes of iron-group nuclei compared to the solar abundance.

  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. Study of shock shape and strength as a function of plasma energy using background oriented schlieren and shadowgraph

    NASA Astrophysics Data System (ADS)

    Singh, Bhavini; Rajendran, Lalit; Giarra, Matthew; Bane, Sally; Vlachos, Pavlos

    2016-11-01

    The formation of a spark is a random, chaotic process. The flow field generated by this spark can be used in flow control and plasma assisted combustion applications. In order to understand the flow field some time after spark discharge (approximately 1 microsecond), it is important to observe the shape and strength of the shockwave immediately following the plasma discharge. It is also important to understand the effect that the energy deposited in the spark gap has on the shock strength and shock shape. We therefore propose a background oriented schlieren (BOS) technique to measure density gradients associated with the spark discharge and hence quantify shock strength. Simultaneous shadowgraph measurements will be used to observe the shape of the shock and compare it with the reconstructed density gradients obtained from BOS measurements.

  8. γ strength function and level density of 208Pb from forward-angle proton scattering at 295 MeV

    NASA Astrophysics Data System (ADS)

    Bassauer, S.; von Neumann-Cosel, P.; Tamii, A.

    2016-11-01

    Background: γ strength functions (GSFs) and level densities (LDs) are essential ingredients of statistical nuclear reaction theory with many applications in astrophysics, reactor design, and waste transmutation. Purpose: The aim of the present work is a test of systematic parametrizations of the GSF recommended by the RIPL-3 database for the case of 208Pb. The upward GSF and LD in 208Pb are compared to γ decay data from an Oslo-type experiment to examine the validity of the Brink-Axel (BA) hypothesis. Methods: The E 1 and M1 parts of the total GSF are determined from high-resolution forward angle inelastic proton scattering data taken at 295 MeV at the Research Center for Nuclear Physics (RCNP), Osaka, Japan. The total LD in 208Pb is derived from the 1- LD extracted with a fluctuation analysis in the energy region of the isovector giant dipole resonance. Results: The E 1 GSF is compared to parametrizations recommended by the RIPL-3 database showing systematic deficiencies of all models in the energy region around neutron threshold. The new data for the poorly known spin-flip M 1 resonance call for a substantial revision of the model suggested in RIPL-3. The total GSF derived from the present data is larger in the PDR energy region than the Oslo data but the strong fluctuations due to the low LD resulting from the double shell closure of 208Pb prevent a conclusion on a possible violation of the BA hypothesis. Using the parameters suggested by RIPL-3 for a description of the LD in 208Pb with the back-shifted Fermi gas model, remarkable agreement between the two experiments spanning a wide excitation energy range is obtained. Conclusions: Systematic parametrizations of the E 1 and M 1 GSF parts need to be reconsidered at low excitation energies. The good agreement of the LD provides an independent confirmation of the approach underlying the decomposition of GSF and LD in Oslo-type experiments.

  9. Effect of the features of functionalized structure on elastic properties and strength of partially-filled brittle porous materials

    NASA Astrophysics Data System (ADS)

    Konovalenko, Igor S.; Shilko, Evgeny V.; Konovalenko, Ivan S.; Vodopjyanov, Egor M.

    2016-11-01

    A two-scale mechanical model of brittle porous material partially filled with plastic filler (inclusions) was developed within the framework of the formalism of movable cellular automaton method. The model was applied to study the mechanical properties of mesoscopic samples with a linear distribution of the local porosity in the depth of the material. Calculation results showed essentially nonlinear dependence of their elastic and strength properties on the degree of pore space filling. It is found that depending on the sign of the gradient of porosity the value of shear strength of partially filled samples can significantly increase or remain constant with increase in the value of the degree of filling.

  10. Is handgrip strength normalized to body weight a useful tool to identify dynapenia and functional incapacity in post-menopausal women?

    PubMed Central

    Dulac, Maude; Boutros, Guy El Hajj; Pion, Charlotte; Barbat-Artigas, Sébastien; Gouspillou, Gilles; Aubertin-Leheudre, Mylène

    2016-01-01

    ABSTRACT Objective To investigate whether handgrip strength normalized to body weight could be a useful clinical tool to identify dynapenia and assess functional capacity in post-menopausal women. Method A total of 136 postmenopausal women were recruited. Body composition (Dual Energy X-ray Absorptiometry [DEXA], Bio-electrical Impedence Analysis [BIA]), grip strength (dynamometer) and functional capacity (senior fitness tests) were evaluated. Dynapenia was established according to a handgrip strength index (handgrip strength divided by body weight (BW) in Kg/KgBW) obtained from a reference population of young women: Type I dynapenic (<0.44 kg/KgBW) and type II dynapenic (<0.35 kg/KgBW). Results The results show a positive correlation between handgrip strength index (in kg/KgBW) and alternate-step test (r=0.30, p<0.001), chair-stand test (r=0.25, p<0.005) and one-leg stance test (r=0.335, p<0.001). The results also showed a significant difference in non-dynapenic compared to type I dynapenic and type II dynapenic for the chair-stand test (Non-dynapenic: 12.0±3.0; Type I: 11.7±2.5; Type II: 10.3±3.0) (p=0.037 and p=0.005, respectively) and the one-leg stance test (Non-dynapenic: 54.2±14.2; Type I: 43.8±21.4; Type II: 35.0±21.8) (p=0.030 and p=0.004, respectively). Finally, a significant difference was observed between type II dynapenic and non-dynapenic for the chair-stand test (p=0.032), but not with type I dynapenic. Conclusion The results showed that handgrip strength was positively correlated with functional capacity. In addition, non-dynapenic women displayed a better functional status when compared to type I and type II dynapenic women. Thus, the determination of the handgrip strength thresholds could be an accessible and affordable clinical tool to identify people at risk of autonomy loss. PMID:27683834

  11. Impact of maximal strength training on work efficiency and muscle fiber type in the elderly: Implications for physical function and fall prevention.

    PubMed

    Wang, Eivind; Nyberg, Stian Kwak; Hoff, Jan; Zhao, Jia; Leivseth, Gunnar; Tørhaug, Tom; Husby, Otto Schnell; Helgerud, Jan; Richardson, Russell S

    2017-02-21

    Although aging is typically associated with a decreased efficiency of locomotion, somewhat surprisingly, there is also a reduction in the proportion of less efficient fast-twitch Type II skeletal muscle fibers and subsequently a greater propensity for falls. Maximal strength training (MST), with an emphasis on velocity in the concentric phase, improves maximal strength, the rate of force development (RFD), and work efficiency, but the impact on muscle morphology in the elderly is unknown. Therefore we evaluated force production, walking work efficiency, and muscle morphology in 11 old (72±3years) subjects before and after MST of the legs. Additionally, for reference, the MST-induced morphometric changes were compared with 7 old (74±6years) subjects who performed conventional strength training (CST), with focus on hypertrophy, as well as 13 young (24±2years) controls. As expected, MST in the old improved maximal strength (68%), RFD (48%), and work efficiency (12%), restoring each to a level similar to the young. However, of importance, these MST-induced functional changes were accompanied by a significant increase in the size (66%) and shift toward a larger percentage (56%) of Type II skeletal muscle fibers, mirroring the adaptations in the hypertrophy trained old subjects, with muscle composition now being similar to the young. In conclusion, MST can increase both work efficiency and Type II skeletal muscle fiber size and percentage in the elderly, supporting the potential role of MST as a countermeasure to maintain both physical function and fall prevention in this population.

  12. 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.

  13. Independent and Combined Association of Muscle Strength and Cardiorespiratory Fitness in Youth With Insulin Resistance and β-Cell Function in Young Adulthood

    PubMed Central

    Grøntved, Anders; Ried-Larsen, Mathias; Ekelund, Ulf; Froberg, Karsten; Brage, Søren; Andersen, Lars B.

    2013-01-01

    OBJECTIVE To examine the independent and combined association of isometric muscle strength of the abdomen and back and cardiorespiratory fitness (CRF) in youth with indices of glucose metabolism in young adulthood among boys and girls from the European Youth Heart Study. RESEARCH DESIGN AND METHODS We used data from a population-based prospective cohort study among youth followed up for up to 12 years (n = 317). In youth, maximal voluntary contractions during isometric back extension and abdominal flexion were determined using a strain-gauge dynamometer and CRF was obtained from a maximal cycle ergometer test. Insulin resistance (homeostasis model assessment of insulin resistance [HOMA-IR]) and β-cell function (homeostasis model assessment of β-cell function [HOMA-B]) were estimated from fasting serum insulin and glucose that were obtained in youth and at follow-up in young adulthood. RESULTS For each 1-SD difference in isometric muscle strength (0.16 N/kg) in youth, fasting insulin, HOMA-IR, and HOMA-B in young adulthood changed by −11.3% (95% CI −17.0 to −5.2), −12.2% (−18.2 to −5.7), and −8.9% (−14.4 to −3.0), respectively, in young adulthood after adjustment for CRF and personal lifestyle and demographic factors. Results for CRF were very similar in magnitude, and the magnitude of associations for both exposures was unchanged with additional adjustment for general or abdominal adiposity in youth. Combined associations of muscle strength and CRF with fasting insulin, HOMA-IR, and HOMA-B were additive, and adolescents in the highest sex-specific tertile for both isometric muscle strength and CRF had the lowest levels of these glucose metabolism outcomes. CONCLUSIONS Increasing muscle strength and CRF should be targets in youth primordial prevention strategies of insulin resistance and β-cell dysfunction. PMID:23579180

  14. Quadriceps Strength, Muscle Activation Failure, and Patient-Reported Function at the Time of Return to Activity in Patients Following Anterior Cruciate Ligament Reconstruction: A Cross-sectional Study

    PubMed Central

    Lepley, Lindsey K.; Palmieri-Smith, Riann M.

    2016-01-01

    Study Design Cross-sectional. Objectives To determine if quadriceps activation failure (QAF) moderates the relationship between quadriceps strength and physical function in individuals post-anterior cruciate ligament (ACL) reconstruction. Background QAF may impair the recovery of physical function post ACL reconstruction, given that QAF reduces strength, and strength is related to physical function. Evidence of this relationship has been found in individuals with knee osteoarthritis, wherein patients with lower strength and greater QAF had lower levels of physical function. Methods Participants consisted of 52 individuals who were cleared for return to activity at an average ± SD of 7.4 ± 1.2 months post ACL reconstruction. QAF was assessed using the superimposed burst technique and quadriceps strength was assessed using concentric isokinetic contractions (Nm/kg). Physical function was quantified using a combined variable of physical (single leg hop for distance) and self-reported function (International Knee Documentation Committee form) calculated using a principal component analysis (PCPF). Simple correlations were then performed to determine the order in which variables were entered into the regression model to evaluate if QAF moderates the relationship between quadriceps strength and physical function. Results The combination of quadriceps strength and the interaction of strength-by-QAF predicted 30% of the variance in physical function (R2=0.30, P<.001; PCPF = -0.61strength + 0.20interaction - 1.896); however the interaction of strength-by-QAF only accounted for 7% of the capabilities of the model (P=.023). Conclusion Physical function is largely influenced by the recovery of quadriceps strength and minimally attenuated by QAF. These data suggest that QAF may affect individuals post ACL reconstruction differently, and to a lesser extent, than knee individuals with knee osteoarthritis. PMID:26471854

  15. PAIN, FUNCTION, AND STRENGTH OUTCOMES FOR MALES AND FEMALES WITH PATELLOFEMORAL PAIN WHO PARTICIPATE IN EITHER A HIP/CORE- OR KNEE-BASED REHABILITATION PROGRAM

    PubMed Central

    Earl-Boehm, Jennifer; Emery, Carolyn; Hamstra-Wright, Karrie; Ferber, Reed

    2016-01-01

    Background Hip exercise has been recommended for females with patellofemoral pain (PFP). It is unknown if males with PFP will benefit from a similar treatment strategy. Hypotheses/Purpose The purpose of this study was to compare improvements in pain, function, and strength between males and females with PFP who participated in either a hip/core or knee rehabilitation program. The directional hypothesis was that females would respond more favorably to the hip/core rehabilitation program and males to the knee program. Study Design Randomized-controlled clinical trial Methods Patients were randomly assigned to a six-week hip/core or knee rehabilitation program. Visual analog scale (VAS), Anterior Knee Pain Scale (AKPS), and hip and knee isometric strength were collected before and after subjects completed the rehabilitation program. Data were analyzed using an intention-to-treat basis. Separate mixed-model analyses of variance (ANOVA) with repeated measures were used to determine changes in VAS and AKPS and strength changes for subjects classified as treatment responders (successful outcome) and non-responders (unsuccessful outcome). Results Regardless of sex or rehabilitation group, VAS (F1,181=206.5; p<.0001) and AKPS (F1,181 = 160.4; p < 0.0001) scores improved. All treatment responders demonstrated improved hip abductor (F1,122 = 6.6; p = 0.007), hip extensor (F1,122 = 19.3; p < 0.0001), and knee extensor (F1,122 = 16.0; p < 0.0001) strength. A trend (F1,122 = 3.6; p = 0.06) existed for an effect of sex on hip external rotator strength change. Males demonstrated a 15.4% increase compared to a 5.0% increase for females. All treatment non-responders had minimal and non-significant (p > 0.05) strength changes. Conclusion On average, males and females with PFP benefitted from either a hip/core or knee rehabilitation program. Subjects with successful outcomes likely had hip and knee weakness that responded well to the

  16. Effect of Loquat Leaf Extract on Muscle Strength, Muscle Mass, and Muscle Function in Healthy Adults: A Randomized, Double-Blinded, and Placebo-Controlled Trial

    PubMed Central

    Choe, Sangmin; Lee, Chang-Hyung; Shin, Jin-Hong

    2016-01-01

    Ursolic acid (UA) is the major active component of the loquat leaf extract (LLE) and several previous studies have indicated that UA may have the ability to prevent skeletal muscle atrophy. Therefore, we conducted a randomized, double-blind, and placebo-controlled study to investigate the effects of the LLE on muscle strength, muscle mass, muscle function, and metabolic markers in healthy adults; the safety of the compound was also evaluated. We examined the peak torque/body weight at 60°/s knee extension, handgrip strength, skeletal muscle mass, physical performance, and metabolic parameters at baseline, as well as after 4 and 12 weeks of intervention. Either 500 mg of LLE (50.94 mg of UA) or a placebo was administered to fifty-four healthy adults each day for 12 weeks; no differences in muscle strength, muscle mass, and physical performance were observed between the two groups. However, the right-handgrip strength of female subjects in the LLE group was found to be significantly better than that of subjects in the control group (P = 0.047). Further studies are required to determine the optimal dose and duration of LLE supplementation to confirm the first-stage study results for clinical application. ClinicalTrials.gov Identifier is NCT02401113. PMID:27999607

  17. Functional gradients in the pericarp of the green coconut inspire asymmetric fibre-composites with improved impact strength, and preserved flexural and tensile properties.

    PubMed

    Graupner, Nina; Labonte, David; Humburg, Heide; Buzkan, Tayfun; Dörgens, Anna; Kelterer, Wiebke; Müssig, Jörg

    2017-02-28

    Here we investigate the mechanical properties and structural design of the pericarp of the green coconut (Cocos nucifera L.). The pericarp showed excellent impact characteristics, and mechanical tests of its individual components revealed gradients in stiffness, strength and elongation at break from the outer to the inner layer of the pericarp. In order to understand more about the potential effect of such gradients on 'bulk' material properties, we designed simple, graded, cellulose fibre-reinforced polylactide (PLA) composites by stacking layers reinforced with fibres of different mechanical properties. Tensile properties of the graded composites were largely determined by the 'weakest' fibre, irrespective of the fibre distribution. However, a graded design led to pronounced asymmetric bending and impact properties. Bio-inspired, asymmetrically graded composites showed a flexural strength and modulus comparable to that of the strongest reference samples, but the elongation at maximum load was dependent on the specimen orientation. The impact strength of the graded composites showed a similar orientation-dependence, and peak values exceeded the impact strength of a non-graded reference composite containing identical fibre fractions by up to a factor of three. In combination, our results show that an asymmetric, systematic variation of fibre properties can successfully combine desirable properties of different fibre types, suggesting new routes for the development of high-performance composites, and improving our understanding of the structure-function relationship of the coconut pericarp.

  18. 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)

  19. The binding of cytochrome c peroxidase and ferricytochrome c. A spectrophotometric determination of the equilibrium association constant as a function of ionic strength.

    PubMed

    Erman, J E; Vitello, L B

    1980-07-10

    Complex formation between cytochrome c peroxidase and ferricytochrome c perturbs the optical absorption spectrum in the Soret band by about 2%. This perturbation can be utilized as a measure of the complex formed in solution and permits the determination of the stoichiometry and the equilibrium association constant for this reaction. At pH 6, in cacodylate/KNO3 buffers, only a 1:1 complex between cytochrome c peroxidase and ferricytochrome c is detected. The equilibrium association constant for the complex has been determined as a function of ionic strength and varies between (6.0 +/- 3.6) x 10(6) M-1 and (2.2 +/- 1.9) x 10(6) M-1 over the ionic strength range 0.01 M to 0.20 M.

  20. Priming for Improved Hand Strength in Persons with Chronic Tetraplegia: A Comparison of Priming-Augmented Functional Task Practice, Priming Alone, and Conventional Exercise Training

    PubMed Central

    Gomes-Osman, Joyce; Tibbett, Jacqueline A.; Poe, Brandon P.; Field-Fote, Edelle C.

    2017-01-01

    Many everyday tasks cannot be accomplished without adequate grip strength, and corticomotor drive to the spinal motoneurons is a key determinant of grip strength. In persons with tetraplegia, damage to spinal pathways limits transmission of signals from motor cortex to spinal motoneurons. Corticomotor priming, which increases descending drive, should increase corticospinal transmission through the remaining spinal pathways resulting in increased grip strength. Since the motor and somatosensory cortices share reciprocal connections, corticomotor priming may also have potential to influence somatosensory function. The purpose of this study was to assess changes in grip (precision, power) force and tactile sensation associated with two different corticomotor priming approaches and a conventional training approach and to determine whether baseline values can predict responsiveness to training. Participants with chronic (≥1 year) tetraplegia (n = 49) were randomized to one of two corticomotor priming approaches: functional task practice plus peripheral nerve somatosensory stimulation (FTP + PNSS) or PNSS alone, or to conventional exercise training (CET). To assess whether baseline corticospinal excitability (CSE) is predictive of responsiveness to training, in a subset of participants, we assessed pre-intervention CSE of the thenar muscles. Participants were trained 2 h daily, 5 days/week for 4 weeks. Thirty-seven participants completed the study. Following intervention, significant improvements in precision grip force were observed in both the stronger and weaker hand in the FTP + PNSS group (effect size: 0.51, p = 0.04 and 0.54, p = 0.03, respectively), and significant improvements in weak hand precision grip force were associated with both PNSS and CET (effect size: 0.54, p = 0.03 and 0.75, p = 0.02, respectively). No significant changes were observed in power grip force or somatosensory scores in any group. Across all groups

  1. Priming for Improved Hand Strength in Persons with Chronic Tetraplegia: A Comparison of Priming-Augmented Functional Task Practice, Priming Alone, and Conventional Exercise Training.

    PubMed

    Gomes-Osman, Joyce; Tibbett, Jacqueline A; Poe, Brandon P; Field-Fote, Edelle C

    2016-01-01

    Many everyday tasks cannot be accomplished without adequate grip strength, and corticomotor drive to the spinal motoneurons is a key determinant of grip strength. In persons with tetraplegia, damage to spinal pathways limits transmission of signals from motor cortex to spinal motoneurons. Corticomotor priming, which increases descending drive, should increase corticospinal transmission through the remaining spinal pathways resulting in increased grip strength. Since the motor and somatosensory cortices share reciprocal connections, corticomotor priming may also have potential to influence somatosensory function. The purpose of this study was to assess changes in grip (precision, power) force and tactile sensation associated with two different corticomotor priming approaches and a conventional training approach and to determine whether baseline values can predict responsiveness to training. Participants with chronic (≥1 year) tetraplegia (n = 49) were randomized to one of two corticomotor priming approaches: functional task practice plus peripheral nerve somatosensory stimulation (FTP + PNSS) or PNSS alone, or to conventional exercise training (CET). To assess whether baseline corticospinal excitability (CSE) is predictive of responsiveness to training, in a subset of participants, we assessed pre-intervention CSE of the thenar muscles. Participants were trained 2 h daily, 5 days/week for 4 weeks. Thirty-seven participants completed the study. Following intervention, significant improvements in precision grip force were observed in both the stronger and weaker hand in the FTP + PNSS group (effect size: 0.51, p = 0.04 and 0.54, p = 0.03, respectively), and significant improvements in weak hand precision grip force were associated with both PNSS and CET (effect size: 0.54, p = 0.03 and 0.75, p = 0.02, respectively). No significant changes were observed in power grip force or somatosensory scores in any group. Across all groups

  2. 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

  3. Strength Training

    MedlinePlus

    ... strengthens your heart and lungs. When you strength train with weights, you're using your muscles to ... see there are lots of different ways to train with weights. Try a few good basic routines ...

  4. 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.

  5. Measurement of the ground-state asymmetry parameter for the decay of sup 29 P

    SciTech Connect

    Masson, G.S.

    1988-01-01

    The ground state asymmetry parameter, A{sub gs}, was measured for the decay of polarized {sup 29}P. From A{sub gs} and the published value for ft{sub 1/2}, the decay's Fermi and Gamow-Teller strengths were deduced. Polarized {sup 29}P was produced by bombarding {sup 28}Si with 3.0 MeV vector polarized deuterons. A free standing wafer of pure natural abundance silicon crystal served as both target and host for the {sup 29}P. The target was heated to 140{degree}C and placed in a 1.0mT magnetic field to lengthen the polarization relaxation time. Positrons emitted in the decay were recorded by two detector telescopes placed at 0{degree}C and 180{degree} relative to the sample's polarization axis. A NaI detector, placed at 90{degree} was used to record gammas in coincidence with positrons, making it possible to simultaneously measure the asymmetries for both the ground state and excited state branches. The ground state asymmetry parameter, A{sub gs}, was deduced from these two asymmetries. The vector coupling constant, calculated form the measured Fermi strength, agrees with the predictions of CVC and with the accepted value for the Cabibbo angle. The measured Gamow-Teller strength agrees with recent calculations by Brown and Wildenthal, and disagree with earlier results of Azuelos and Kitching.

  6. 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.

  7. 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.

  8. Health and physical function predicting strength and balance training adoption: a community-based study among individuals aged 75 and older.

    PubMed

    Aartolahti, Eeva; Hartikainen, Sirpa; Lönnroos, Eija; Häkkinen, Arja

    2014-10-01

    This study was conducted to determine the characteristics of health and physical function that are associated with not starting strength and balance training (SBT). The study population consisted of 339 community-dwelling individuals (75-98 years, 72% female). As part of a population-based intervention study they received comprehensive geriatric assessment, physical activity counseling, and had the opportunity to take part in SBT at the gym once a week. Compared with the SBT-adopters, the nonadopters (n = 157, 46%) were older and less physically active, had more comorbidities and lower cognitive abilities, more often had sedative load of drugs or were at the risk of malnutrition, had lower grip strength and more instrumental activities of daily living (IADL) difficulties, and displayed weaker performance in Berg Balance Scale and Timed Up and Go assessments. In multivariate models, higher age, impaired cognition, and lower grip strength were independently associated with nonadoption. In the future, more individually-tailored interventions are needed to overcome the factors that prevent exercise initiation.

  9. {gamma}-ray strength function for {sup 116,117}Sn with the pygmy dipole resonance balanced in the photoneutron and neutron capture channels

    SciTech Connect

    Utsunomiya, H.; Kamata, M.; Kondo, T.; Itoh, O.; Akimune, H.; Yamagata, T.; Goriely, S.; Toyokawa, H.; Lui, Y.-W.; Hilaire, S.; Koning, A. J.

    2009-11-15

    Photoneutron cross sections were measured for {sup 117}Sn and {sup 116}Sn near the neutron thresholds at 6.94 and 9.56 MeV, respectively, with quasi-monochromatic laser-Compton scattering {gamma} rays. The {sup 117}Sn cross section, which is strongly enhanced near the low threshold, provides evidence for the presence of extra {gamma} strength in the low-energy tail of the giant dipole resonance. A coherent analysis of the photoneutron data for {sup 117}Sn together with the neutron capture on {sup 116}Sn shows that the {gamma}-ray strength function is balanced in the photoneutron and neutron capture channels in terms of the microscopic Hartree-Fock-Bogoliubov plus quasiparticle random-phase approximation model of E1 strength combined with a pygmy E1 resonance at 8.5 MeV. The high-energy part of the pygmy resonance is also suggested in the photoneutron cross section for {sup 116}Sn.

  10. Building a dishonest signal: the functional basis of unreliable signals of strength in males of the two-toned fiddler crab, Uca vomeris.

    PubMed

    Bywater, Candice L; Seebacher, Frank; Wilson, Robbie S

    2015-10-01

    Males of many species use signals during aggressive contests to communicate their fighting capacity. These signals are usually reliable indicators of an individual's underlying quality; however, in several crustacean species, displays of weapons do not always accurately reflect the attribute being advertised. Male fiddler crabs possess one enlarged claw that is used to attract females and to intimidate opponents during territorial contests. After the loss of their major claw, males can regenerate a replacement claw that is similar in size but considerably weaker. As this inferior weapon can still be used to successfully intimidate rivals, it represents one of the clearest cases of unreliable signalling of strength during territorial contests. We investigated the functional mechanisms that govern signal reliability in the two-toned fiddler crab, Uca vomeris. Male U. vomeris exhibit both reliable and unreliable signals of strength via the expression of original and regenerated claw morphs. We examined the morphological, biomechanical and biochemical characteristics of original and regenerated claws to establish the best predictors of variation in claw strength. For a given claw size, regenerated claws have less muscle mass than original claws, and for a given muscle mass, regenerated claws were significantly weaker than original claws. The mechanical advantage was also lower in regenerated claws compared with original claws. However, the activity of three catabolic enzymes did not differ between claw types. We conclude that the structural and physiological predictors of force production influence the frequencies of reliable and unreliable signals of strength in U. vomeris. This study furthers our understanding of the proliferation of unreliable signals in natural populations.

  11. No increase of the blood oxygenation level-dependent functional magnetic resonance imaging signal with higher field strength: implications for brain activation studies.

    PubMed

    Seehafer, Jörg U; Kalthoff, Daniel; Farr, Tracy D; Wiedermann, Dirk; Hoehn, Mathias

    2010-04-14

    Experimental data up to 7.0 T show that the blood oxygenation level-dependent (BOLD) signal of functional magnetic resonance imaging (fMRI) increases with higher magnetic field strength. Although several studies at 11.7 T report higher BOLD signal compared with studies at 7.0 T, no direct comparison at these two field strengths has been performed under the exact same conditions. It therefore remains unclear whether the expected increase of BOLD effect with field strength will still continue to hold for fields >7.0 T. To examine this issue, we compared the BOLD activation signal at 7.0 and 11.7 T with the two common sequences, spin-echo (SE) and gradient-echo (GE) echo planar imaging (EPI). We chose the physiologically well controlled rat model of electrical forepaw stimulation under medetomidine sedation. While a linear to superlinear increase in activation with field strengths up to 7.0 T was reported in the literature, we observed no significant activation difference between 7.0 and 11.7 T with either SE or GE. Discussing the results in light of the four-component model of the BOLD signal, we showed that at high field only two extravascular contributions remain relevant, while both intravascular components vanish. Constancy of the BOLD effect is discussed due to motional narrowing, i.e., susceptibility gradients become so strong that phase variance of diffusing spins decreases and therefore the BOLD signal also decreases. This finding will be of high significance for the planning of future human and animal fMRI studies at high fields and their quantitative analysis.

  12. Evaluation of Respiratory Muscle Strength and Pulmonary Function in Patients with Charcot-Marie-Tooth Disease Type 2.

    PubMed

    Garcez, Catarina Andrade; Neves, Eduardo Luis Aquino; Melo, Saulo Maia D''avila; Nunes, Paula Santos; Barreto, Lidiane Carine Lima; Costa, Iandra Maria Pinheiro; Souza, Cynthia Coelho; Rezende, Rejane Lenier; Araújo, Adriano Antunes de Souza

    2015-01-01

    The aim of this study was to evaluate the pulmonary condition in a large family with Charcot-Marie-Tooth disease type 2 (CMT2). Eighteen participants diagnosed with CMT2 and 20 healthy individuals were evaluated by spirometry and maximal expiratory and maximal inspiratory pressures (MEP and MIP, respectively). Clinical disability was measured with CMT neuropathy score (CMTNS; range 0-36). One control group (CG) comprising 20 individuals, matched for age, sex and body mass index, were used for comparison. Eight patients were female (44.5%) and 10 patients were male (55.5%); mean age was 31.8 years (range 11-79) and CMTNS range was 6-26. Differences between CMT2 and CG in the spirometry and respiratory muscle strength were statistically significant for all dimensions. There were significant correlations between CMTNS and MIP (Pearson = -0.581) and MEP (Pearson = -0.5090). The results of this study show that patients with CMT, in spite of not showing clinical signs of advanced respiratory impairment, may present subclinical respiratory changes. The respiratory comprise in the CMT disease can be silent and insidious without presenting characteristic clinical signals.

  13. 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

  14. 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

  15. 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

  16. Restricted Blood Flow Exercise in Sedentary, Overweight African-American Females May Increase Muscle Strength and Decrease Endothelial Function and Vascular Autoregulation

    PubMed Central

    Bond, Vernon; Curry, Bryan Heath; Kumar, Krishna; Pemminati, Sudhakar; Gorantla, Vasavi Rakesh; Kadur, Kishan; Millis, Richard Mark

    2017-01-01

    Objectives: Exercise with partially restricted blood flow is a low-load, low-intensity resistance training regimen which may have the potential to increase muscle strength in the obese, elderly and frail who are unable to do high-load training. Restricted blood flow exercise has also been shown to affect blood vessel function variably and can, therefore, contribute to blood vessel dysfunction. This pilot study tests the hypothesis that unilateral resistance training of the leg extensors with partially restricted blood flow increases muscle strength and decreases vascular autoregulation. Methods: The subjects were nine normotensive, overweight, young adult African-Americans with low cardiorespiratory fitness who underwent unilateral training of the quadriceps’ femoris muscles with partially restricted blood flow at 30% of the 1-repetition maximum (1-RM) load for 3 weeks. The 1-RM load and post-occlusion blood flow to the lower leg (calf) were measured during reactive hyperemia. Results: The 1-RM load increased in the trained legs from 77 ± 3 to 84 ± 4 kg (P < 0.05) in the absence of a significant effect on the 1-RM load in the contralateral untrained legs (P > 0.1). Post-occlusion blood flow decreased significantly in the trained legs from 19 ± 2 to 13 ± 2 mL· min-1· dL-1 (P < 0.05) and marginally in the contralateral untrained legs from 18 ± 2 to 16 ± 1 mL· min-1· dL-1 (P = 0.09). Changes in post-occlusion blood flow to the skin overlying the trained and the contralateral untrained muscles were not significant. Conclusion: These results demonstrate that restricted blood flow exercise, which results in significant gains in muscle strength, may produce decrements in endothelial dysfunction and vascular autoregulation. Future studies should determine whether pharmacopuncture plays a role in treatments for such blood vessel dysfunction. PMID:28392959

  17. Estimation of {sup 237}U Level Density and Radiative Strength Functions from the (n-bar,{gamma}) Reaction

    SciTech Connect

    Sukhovoj, Anatoly M.; Khitrov, Valery A.; Maslov, Vladimir M.

    2009-01-28

    Intensity distribution of the primary {gamma}-transitions following resonance neutron capture in {sup 236}U about the mean value was approximated in different energy intervals of these quanta and neutrons. Extrapolation of the obtained functions to zero registration threshold of {gamma}-transitions allowed independent estimation of the expected level number of both parities for spin values J = 1/2, 3/2 and sum of radiative widths for both electric and magnetic gamma-transitions to levels with excitation energy up to {approx_equal}2.3 MeV.

  18. Density functional theoretical study of the S-H bond strengths in organic thiols and a model MoS cluster

    SciTech Connect

    Franz, James A; Dupuis, Michel; Camaioni, Donald M; Birnbaum, Jerome C

    2003-09-11

    Hydrosulfurization (HDS) is carried out by exposure of a substrate fuel source to a regime of hydrogen pressure and high temperatures in the presence of Co/MoS or Ni/MoS catalysts on γ-Al2O3 supports [Topsoe et al., 1996]. At temperatures of HDS, and in the presence of organosulfur structures, thermal free radical chemistry will accompany or even dominate many pathways of organic structure transformation. Hydrogenation and dehydrogenation of organic structure will be particularly sensitive to the nature of organosulfur intermediates. A major pathway of hydrogenolysis and hydrogenation is initiated by the transfer of hydrogen atom from a closed shell molecule to an acceptor [Rüchardt et al. 1997]. This reaction is the starting point for hydrogenation of unsaturated organic structure. The reaction is the reverse of the disproportionation reaction of two free radicals, and depends on the enthalpy change of the forward reaction. To predict the rate of reaction in eq 1, key information required is the bond strength of Hº = H* R-H + CH2=CH2 R• + CH3=CH2• (1) the participating organic or catalyst function (R-H, eq 1). In this paper, we present results of a density functional theory investigation of bond strengths of a series of thiols, and of the HDS prototype model, CpMo[(µ-S)2(µ-SH)2]MoCp, 1, Cp = η5-C5H5 [Rakowski DuBois, 1998]. This system is representative of a class of MoS cluster systems that are models of exfoliated MoS2 catalysts [Curtiss, et al. 1996]. The level of theory for prediction of accurate (ca. 1-2 kcal/mol error) S-H bonds is explored. The reactivity of the prototype MoSH functionality in initiating homolytic hydrogenation steps is provided by the computational predictions.

  19. The effect of exergames on functional strength, anaerobic fitness, balance and agility in children with and without motor coordination difficulties living in low-income communities.

    PubMed

    Smits-Engelsman, Bouwien C M; Jelsma, L Dorothee; Ferguson, Gillian D

    2016-07-13

    Children with Developmental Coordination Disorder (DCD) are physically less active, preferring more sedentary behavior and are at risk of developing health problems or becoming overweight. 18 children (age 6-10years) with lower levels of motor coordination attending a primary school in a low-income community in South Africa (score on Movement Assessment Battery for Children Second edition equal to or below the 5th percentile) were selected to participate in the study and were age-matched with typically developing peers (TD). Both groups of children engaged in 20min of active Nintendo Wii Fit gaming on the balance board, twice a week for a period of five weeks. All children were tested before and after the intervention using the lower limb items of the Functional Strength Measurement, the 5×10 meter sprint test, the 5×10 meter slalom sprint test, and the Balance, Running speed and Agility subtest of the Bruininks Oseretsky Test of Motor Proficiency 2nd edition (BOT-2). After intervention, both groups of children improved in functional strength and anaerobic fitness. The magnitude of these changes was not related to participant's motor coordination level. However, differences in change between the TD and DCD group were apparent on the motor performance tests; children with DCD seemed to benefit more in balance skills of the BOT-2, while the TD children improved more in the Running speed and Agility component of the BOT-2. Compliance to the study protocol over 5weeks was high and the effect on physical functioning was shown on standardized measures of physical performance validated for children with and without DCD.

  20. Robotics and gaming to improve ankle strength, motor control, and function in children with cerebral palsy--a case study series.

    PubMed

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

    2013-03-01

    The objective of this study was to investigate the feasibility of game-based robotic training of the ankle in children with cerebral palsy (CP). The design was a case study, 12 weeks intervention, with no follow-up. The setting was a university research laboratory. The participants were a referred sample of three children with cerebral palsy, age 7-12, all male. All completed the intervention. Participants trained on the Rutgers Ankle CP system for 36 rehabilitation sessions (12 weeks, three 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. 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). 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. 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.

  1. 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

  2. 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

  3. Spectroscopic studies of neutron-deficient light nuclei: decay properties of 21Mg, 25Si and 26P

    NASA Astrophysics Data System (ADS)

    Thomas, J.-C.; Achouri, L.; ńystö, J.; Béraud, R.; Blank, B.; Canchel, G.; Czajkowski, S.; Dendooven, P.; Ensallem, A.; Giovinazzo, J.; Guillet, N.; Honkanen, J.; Jokinen, A.; Laird, A.; Lewitowicz, M.; Longour, C.; de Oliveira Santos, F.; Stanoiu, M.

    2003-09-01

    Neutron-deficient nuclei with Tz equals to -3/2 and -2 have been produced at the GANIL/LISE3 facility in fragmentation reactions of a 95 MeV/u 36Ar primary beam in a 12C target. For the first time, β-delayed proton and β-γ emission has been simultaneously observed in the decay of 21Mg, 25Si and 26P. The decay scheme of the latter is proposed and the Gamow-Teller strength distribution in its β decay is compared to shell-model calculations based on the USD interaction. The B(GT) values derived from the absolute measurement of the β-branching ratios are in agreement with the quenching factor of about 60% obtained for allowed Gamow-Teller transitions in this mass region. A precise half-life of 43.7 (6) ms was determined for 26P, the β-2p emission of which was studied. The expected contribution of spectroscopic studies of neutron-rich nuclei is discussed with respect to the mirror asymmetry phenomenon occuring in analogous β decays.

  4. Acupuncture for Functional Dyspepsia: What Strength Does It Have? A Systematic Review and Meta-Analysis of Randomized Controlled Trials

    PubMed Central

    Li, Jing; Li, Bo; Hu, Ya-Cai; Cai, Qiu-Han

    2016-01-01

    Background. Although the effectiveness of acupuncture therapy on functional dyspepsia (FD) has been systematically reviewed, the available reports are still contradictive and no robust evidence has been provided to date. Objective. To assess the current evidence of high quality on the effects of acupuncture for patients with FD. Methods. A comprehensive literature database search was conducted to identify randomized controlled trials (RCTs) comparing acupuncture therapies (including manual acupuncture and electroacupuncture) to sham acupuncture and medication use. A meta-analysis was performed following a strict methodology. Results. 16 RCTs involving 1436 participants were included. The majority of the trials were determined to be of low quality. Positive results were found for acupuncture in improving the Nepean Dyspepsia Index (NDI) and scores of the MOS 36-Item Short-Form Health Survey (SF-36), as well as in alleviating relevant symptoms (especially postprandial fullness and early satiation) of FD patients. Conclusion. Based on current available evidence, acupuncture therapy achieves statistically significant effect for FD in comparison with sham acupuncture and is superior to medication (prokinetic agents) in improving the symptoms and quality of life of FD patients. Nonetheless, despite stringent methodological analyses, the conclusion of our review still needs to be strengthened by additional RCTs of higher quality. PMID:28119758

  5. 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

  6. Acupuncture for Functional Dyspepsia: What Strength Does It Have? A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

    PubMed

    Pang, Bo; Jiang, Tao; Du, Yuan-Hao; Li, Jing; Li, Bo; Hu, Ya-Cai; Cai, Qiu-Han

    2016-01-01

    Background. Although the effectiveness of acupuncture therapy on functional dyspepsia (FD) has been systematically reviewed, the available reports are still contradictive and no robust evidence has been provided to date. Objective. To assess the current evidence of high quality on the effects of acupuncture for patients with FD. Methods. A comprehensive literature database search was conducted to identify randomized controlled trials (RCTs) comparing acupuncture therapies (including manual acupuncture and electroacupuncture) to sham acupuncture and medication use. A meta-analysis was performed following a strict methodology. Results. 16 RCTs involving 1436 participants were included. The majority of the trials were determined to be of low quality. Positive results were found for acupuncture in improving the Nepean Dyspepsia Index (NDI) and scores of the MOS 36-Item Short-Form Health Survey (SF-36), as well as in alleviating relevant symptoms (especially postprandial fullness and early satiation) of FD patients. Conclusion. Based on current available evidence, acupuncture therapy achieves statistically significant effect for FD in comparison with sham acupuncture and is superior to medication (prokinetic agents) in improving the symptoms and quality of life of FD patients. Nonetheless, despite stringent methodological analyses, the conclusion of our review still needs to be strengthened by additional RCTs of higher quality.

  7. 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.

  8. Hand grips strength effect on motor function in human brain using fMRI: a pilot study

    NASA Astrophysics Data System (ADS)

    Ismail, S. S.; Mohamad, M.; Syazarina, S. O.; Nafisah, W. Y.

    2014-11-01

    Several methods of motor tasks for fMRI scanning have been evolving from simple to more complex tasks. Motor tasks on upper extremity were applied in order to excite the increscent of motor activation on contralesional and ipsilateral hemispheres in brain. The main objective of this study is to study the different conditions for motor tasks on upper extremity that affected the brain activation. Ten healthy right handed with normal vision (3 male and 7 female, age range=20-30 years, mean=24.6 years, SD=2.21) participated in this study. Prior to the scanning, participants were trained on hand grip tasks using rubber ball and pressure gauge tool outside the scanner. During fMRI session, a block design with 30-s task blocks and alternating 30-s rest periods was employed while participants viewed a computer screen via a back projection-mirror system and instructed to follow the instruction by gripping their hand with normal and strong grips using a rubber ball. Statistical Parametric mapping (SPM8) software was used to determine the brain activation. Both tasks activated the primary motor (M1), supplementary motor area (SMA), dorsal and ventral of premotor cortex area (PMA) in left hemisphere while in right hemisphere the area of primary motor (M1) somatosensory was activated. However, the comparison between both tasks revealed that the strong hand grip showed the higher activation at M1, PMA and SMA on left hemisphere and also the area of SMA on right hemisphere. Both conditions of motor tasks could provide insights the functional organization on human brain.

  9. Mitochondrial function after liver preservation in high or low ionic-strength solutions: a comparison between UW-based and sucrose-based solution.

    PubMed

    Somov, A Y; Semenchenko, O A; Green, C J; Petrenko, A Y; Fuller, B J

    2009-01-01

    In this study we evaluated mitochondrial function after liver cold storage and normothermic reperfusion. The preservation solutions were: modified University of Wisconsin (mod UW) and sucrose-based solution (SBS). After cold preservation liver was re-perfused for 1 hour in vitro with Krebs-Ringer buffer at 37 degree C. Samples of tissue were taken for ATP determination. Mitochondrial respiratory parameters, succinate oxidase complex activity, mitochondrial H+- ATPase and intramitochondrial potassium concentration were assayed. It was shown, that brief (1 hour) cold storage and subsequent normothermic reperfusion revealed no difference in liver ATP content between mod UW and SBS groups but resulted in a gradual decrease of 50 percent after 24-hour storage and reperfusion. Mitochondrial potassium ion concentration increased by 40 percent after 1-hour cold storage in the mod UW as compared to control (P value less than 0.05) and SBS. After brief cold storage ADP and uncoupler-stimulated respiration increased by 120 percent in SBS group, unlike mod UW, when succinate was used as substrate, and was more pronounced after 24 hour. Succinate oxidase complex activity did not change over either cold storage or warm reperfusion. Mitochondrial H+-ATPase activities in SBS and mod UW did not differ and both were inhibited after 24-hour cold storage. Our data demonstrate that low ionic strength preservation solution can substantially modulate mitochondrial energy turnover due to substrate oxidation increase. Many of the changes in mitochondrial function follow brief exposure to low temperatures.

  10. 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

  11. 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.

  12. 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

  13. Study of Weak Interactions with Beta-Alpha Angular Correlations and the Positive Beta Decay of NITROGEN-18 and OXYGEN-14.

    NASA Astrophysics Data System (ADS)

    Hernandez, Ana Maria

    1982-03-01

    (pi)-exchange NN interaction F(,(pi)). The resulting value, independent of the nuclear model, is F(,(pi)) = (0.4 (+OR -) 1.1) x 10('-6). In the second experiment the Gamow-Teller (beta) decay from the ('14)O O('+) ground state to the 3.948 MeV 1('+) level in ('14)N has been studied by observing (gamma) rays from the de-excitation of the 3.948 and 2.313 MeV levels in ('14)N. We measured a branching ratio of (5.28 (+OR-) 0.23) x 10('-4) relative to the superallowed Fermi decay to the 2.313 MeV level, and deduce ft = 1446 (+OR -) 63 sec. The corresponding Gamow-Teller transition strength is B(GT) = 2.73 (+OR-) 0.12. This value is about 40% lower than predicted by several widely used shell model calculations, and may suggest appreciable quenching by mesonic currents.

  14. 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.

  15. 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.

  16. Compromised bone strength index in the hemiparetic distal tibia epiphysis among chronic stroke patients: the association with cardiovascular function, muscle atrophy, mobility, and spasticity

    PubMed Central

    Pang, Marco Y.C.; Ashe, Maureen C.; Eng, Janice J.

    2011-01-01

    Purpose To identify the determinants of the bone strength index (BSI) at the distal tibia in chronic stroke patients. Methods Sixty-three chronic stroke survivors underwent scanning of the distal tibia at the 4% site on both sides using peripheral quantitative computed tomography. The primary outcomes were trabecular bone mineral density (BMD) (mg/cm3), total BMD (mg/cm3), total bone area (mm2), and BSI (g2/cm4). Cardiovascular fitness, leg lean mass, gait velocity, and spasticity were also measured. Results Scans from 45 subjects were deemed to have acceptable quality and were included for subsequent analysis. The paretic side had significantly lower trabecular BMD, total BMD, and BSI than the non-paretic side (p<0.05). However, the total bone area demonstrated no significant side-to-side difference (p>0.05). After adjusting for relevant biological factors, peakoxygen consumption, leg muscle mass, gait velocity remained positively associated with tibial BSI on both sides (R2 change=6.9–14.2%), whereas spasticity of the paretic leg was negatively associated with tibial BSI on the same side (R2 change=4.8%). Conclusions Cardiovascular function, muscle atrophy, mobility, and spasticity are independently associated with BSI of the distal tibia epiphysis among chronic stroke patients. PMID:19882095

  17. 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

  18. 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.

  19. 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

  20. 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

  1. 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…

  2. 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.

  3. Spin dipole nuclear matrix elements for double beta decay nuclei by charge-exchange reactions

    NASA Astrophysics Data System (ADS)

    Ejiri, H.; Frekers, D.

    2016-11-01

    Spin dipole (SD) strengths for double beta-decay (DBD) nuclei were studied experimentally for the first time by using measured cross sections of (3He, t) charge-exchange reactions (CERs). Then SD nuclear matrix elements (NMEs) {M}α ({{SD}}) for low-lying 2- states were derived from the experimental SD strengths by referring to the experimental α = GT (Gamow-Teller) and α = F (Fermi) strengths. They are consistent with the empirical NMEs M({{SD}}) based on the quasi-particle model with the empirical effective SD coupling constant. The CERs are used to evaluate the SD NME, which is associated with one of the major components of the neutrino-less DBD NME.

  4. The Pavlovian "principle of strength".

    PubMed

    Windholz, G

    1995-01-01

    The Pavlovian principle of strength assumed that the magnitude of the conditional response is a linear function of the intensity of the external conditional stimulus. But experiments failed to provide evidence for the universality of the principle. The Pavlovians tried to identify conditions that distorted the linearity of this relationship. Some of the disturbing conditions were external and some were internal intervening variables. It is possible that the relation between the strength of the conditional stimulus and the magnitude of the conditional response is not linear but logarithmic. Pavlov acknowledged the lack of experimental evidence to support the principle of strength in its original form.

  5. 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%.

  6. Reinvestigation of the beta-decay of 110Mo

    NASA Astrophysics Data System (ADS)

    Wang, J. C.; Dendooven, P.; Hankonen, S.; Huikari, J.; Jokinen, A.; Kolhinen, V. S.; Lhersonneau, G.; Nieminen, A.; Peräjärvi, K.; Rinta-Antila, S.; Äystö, J.

    2004-01-01

    The beta-decay of the neutron-rich nucleus 110Mo, separated by the IGISOL on-line mass separator from other fission products, has been investigated by using beta-gamma and gamma-gamma coincidence techniques. The decay scheme of 110Mo has been revised, including 3 new excited states and 7 new γ transitions in 110Tc. The β -feedings were measured and log {ft} values and B(GT) values were deduced based on a Q_{β}-value from systematics. Three excited 1 + states in 110Tc fed by spin-flip allowed-unhindered beta transitions were identified. The deduced beta-decay strengths are compared with the Gamow-Teller strength distribution obtained from a macroscopic-microscopic calculation. The role of the asymptotic quantum numbers in the context of the allowed beta-decay is discussed.

  7. Neutron-$$\\gamma$$ competition for β-delayed neutron emission

    DOE PAGES

    Mumpower, Matthew Ryan; Kawano, Toshihiko; Moller, Peter

    2016-12-19

    Here we present a coupled quasiparticle random phase approximation and Hauser-Feshbach (QRPA+HF) model for calculating delayed particle emission. This approach uses microscopic nuclear structure information, which starts with Gamow-Teller strength distributions in the daughter nucleus and then follows the statistical decay until the initial available excitation energy is exhausted. Explicitly included at each particle emission stage is γ-ray competition. We explore this model in the context of neutron emission of neutron-rich nuclei and find that neutron-γ competition can lead to both increases and decreases in neutron emission probabilities, depending on the system considered. Finally, a second consequence of this formalismmore » is a prediction of more neutrons on average being emitted after β decay for nuclei near the neutron drip line compared to models that do not consider the statistical decay.« less

  8. Neutron-$\\gamma$ competition for β-delayed neutron emission

    SciTech Connect

    Mumpower, Matthew Ryan; Kawano, Toshihiko; Moller, Peter

    2016-12-19

    Here we present a coupled quasiparticle random phase approximation and Hauser-Feshbach (QRPA+HF) model for calculating delayed particle emission. This approach uses microscopic nuclear structure information, which starts with Gamow-Teller strength distributions in the daughter nucleus and then follows the statistical decay until the initial available excitation energy is exhausted. Explicitly included at each particle emission stage is γ-ray competition. We explore this model in the context of neutron emission of neutron-rich nuclei and find that neutron-γ competition can lead to both increases and decreases in neutron emission probabilities, depending on the system considered. Finally, a second consequence of this formalism is a prediction of more neutrons on average being emitted after β decay for nuclei near the neutron drip line compared to models that do not consider the statistical decay.

  9. 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.

  10. 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.

  11. β -decay properties of neutron-rich rare-earth isotopes

    NASA Astrophysics Data System (ADS)

    Sarriguren, P.

    2017-01-01

    In this paper, β -decay properties of even-even neutron-rich isotopes in the rare-earth mass region are studied within a microscopic theoretical approach based on a proton-neutron quasiparticle random-phase approximation. The underlying mean field is constructed self-consistently from a deformed Hartree-Fock calculation with Skyrme interactions and pairing correlations to which particle-hole and particle-particle residual interactions are added. Nuclei in this mass region participate in the astrophysical rapid neutron capture process and are directly involved in the generation of the rare-earth peak in the isotopic abundance pattern centered at A ≃160 . The energy distributions of the Gamow-Teller strength as well as the β -decay half-lives and the β -delayed neutron-emission probabilities are discussed and compared with the available experimental information and with calculations based on different approaches.

  12. 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.

  13. Precision evaluation of the 71Ga(νe,e- ) solar neutrino capture rate from the (3He,t ) charge-exchange reaction

    NASA Astrophysics Data System (ADS)

    Frekers, D.; Adachi, T.; Akimune, H.; Alanssari, M.; Brown, B. A.; Cleveland, B. T.; Ejiri, H.; Fujita, H.; Fujita, Y.; Fujiwara, M.; Gavrin, V. N.; Harakeh, M. N.; Hatanaka, K.; Holl, M.; Iwamoto, C.; Lennarz, A.; Okamoto, A.; Okamura, H.; Suzuki, T.; Tamii, A.

    2015-03-01

    A precision measurement of the 71Ga(3He,t ) 71Ge charge-exchange reaction was performed. By using a rather complete set of theoretical form factors to describe the cross-section angular distributions over a large angular range, the Gamow-Teller strength distribution up to the effective neutron-separation energy in 71Ge was extracted. The data and the analysis constrain the 71Ga(νe,e- ) solar neutrino rate in a neutrino nonoscillation scenario. For nonoscillating neutrinos we report a solar neutrino capture rate of 122.4 ±3.4 (stat ) ±1.1 (sys ) SNU, which is lower than the presently accepted value of 132 ±18 SNU, though not in disagreement given the quoted errors.

  14. Half-life and branching ratios for the β decay of 38Ca

    NASA Astrophysics Data System (ADS)

    Blank, B.; Thomas, J.-C.; Ascher, P.; Audirac, L.; Bacquias, A.; Cáceres, L.; Canchel, G.; Daudin, L.; de Oliveira Santos, F.; Didierjean, F.; Gerbaux, M.; Giovinazzo, J.; Grévy, S.; Kurtukian Nieto, T.; Matea, I.; Munoz, F.; Roche, M.; Serani, L.; Smirnova, N.; Souin, J.

    2015-01-01

    In an experiment at the LISE3 facility of GANIL, we have studied with high precision the decay of 38Ca. The LISE3 facility allowed to produce close to pure samples of the nuclide of interest. We measured the half-life of this nucleus to be 443.63(35)ms, whereas the super-allowed branching ratio was determined to be 77.14(35)%. Both data are in nice agreement with previous high-precision measurements and thus improve the overall precision of the experimental inputs to determine the corrected value for this nucleus. We also compare the experimental Gamow-Teller strength distribution with theoretical shell-model predictions. Finally, future opportunities at LISE3 are discussed.

  15. 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)

  16. 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…

  17. The primary function of gp130 signaling in osteoblasts is to maintain bone formation and strength, rather than promote osteoclast formation.

    PubMed

    Johnson, Rachelle W; Brennan, Holly J; Vrahnas, Christina; Poulton, Ingrid J; McGregor, Narelle E; Standal, Therese; Walker, Emma C; Koh, Thuan-Tzen; Nguyen, Huynh; Walsh, Nicole C; Forwood, Mark R; Martin, T John; Sims, Natalie A

    2014-06-01

    Interleukin-6 (IL-6) family cytokines act via gp130 in the osteoblast lineage to stimulate the formation of osteoclasts (bone resorbing cells) and the activity of osteoblasts (bone forming cells), and to inhibit expression of the osteocyte protein, sclerostin. We report here that a profound reduction in trabecular bone mass occurs both when gp130 is deleted in the entire osteoblast lineage (Osx1Cre gp130 f/f) and when this deletion is restricted to osteocytes (DMP1Cre gp130 f/f). This was caused not by an alteration in osteoclastogenesis, but by a low level of bone formation specific to the trabecular compartment. In contrast, cortical diameter increased to maintain ultimate bone strength, despite a reduction in collagen type 1 production. We conclude that osteocytic gp130 signaling is required for normal trabecular bone mass and proper cortical bone composition.

  18. Semiphenomenological approximation of the sums of experimental radiative strength functions for dipole gamma transitions of energy E γ below the neutron binding energy B n for mass numbers in the range 40 ≤ A ≤ 200

    NASA Astrophysics Data System (ADS)

    Sukhovoj, A. M.; Furman, W. I.; Khitrov, V. A.

    2008-06-01

    The sums of radiative strength functions for primary dipole gamma transitions, k( E1) + k( M1), are approximated to a high precision by a superposition of two functional dependences in the energy range 0.5 < E 1 < B n - 0.5 MeV for the 40K, 60Co, 71,74Ge, 80Br, 114Cd, 118Sn, 124,125Te, 128I, 137,138,139Ba, 140La, 150Sm, 156,158Gd, 160Tb, 163,164,165Dy, 166Ho, 168Er, 170Tm, 174Yb, 176,177Lu, 181Hf, 182Ta, 183,184,185,187W, 188,190,191,193Os, 192Ir, 196Pt, 198Au, and 200Hg nuclei. It is shown that, in any nuclei, radiative strength functions are a dynamical quantity and that the values of k( E1) + k( M1) for specific energies of gamma transitions and specific nuclei are determined by the structure of decaying and excited levels, at least up to the neutron binding energy B n .

  19. Semiphenomenological approximation of the sums of experimental radiative strength functions for dipole gamma transitions of energy E{sub {gamma}}below the neutron binding energy B{sub n} for mass numbers in the range 40 {<=} A {<=} 200

    SciTech Connect

    Sukhovoj, A. M. Furman, W. I. Khitrov, V. A.

    2008-06-15

    The sums of radiative strength functions for primary dipole gamma transitions, k(E1) + k(M1), are approximated to a high precision by a superposition of two functional dependences in the energy range 0.5 < E{sub 1} < B{sub n} - 0.5 MeV for the {sup 40}K, {sup 60}Co, {sup 71,74}Ge, {sup 80}Br, {sup 114}Cd, {sup 118}Sn, {sup 124,125}Te, {sup 128}I, {sup 137,138,139}Ba, {sup 140}La, {sup 150}Sm, {sup 156,158}Gd, {sup 160}Tb, {sup 163,164,165}Dy, {sup 166}Ho, {sup 168}Er, {sup 170}Tm, {sup 174}Yb, {sup 176,177}Lu, {sup 181}Hf, {sup 182}Ta, {sup 183,184,185,187}W, {sup 188,190,191,193}Os, {sup 192}Ir, {sup 196}Pt, {sup 198}Au, and {sup 200}Hg nuclei. It is shown that, in any nuclei, radiative strength functions are a dynamical quantity and that the values of k(E1) + k(M1) for specific energies of gamma transitions and specific nuclei are determined by the structure of decaying and excited levels, at least up to the neutron binding energy B{sub n}.

  20. Multiple roads lead to Rome: combined high-intensity aerobic and strength training vs. gross motor activities leads to equivalent improvement in executive functions in a cohort of healthy older adults.

    PubMed

    Berryman, Nicolas; Bherer, Louis; Nadeau, Sylvie; Lauzière, Séléna; Lehr, Lora; Bobeuf, Florian; Lussier, Maxime; Kergoat, Marie Jeanne; Vu, Thien Tuong Minh; Bosquet, Laurent

    2014-01-01

    The effects of physical activity on cognition in older adults have been extensively investigated in the last decade. Different interventions such as aerobic, strength, and gross motor training programs have resulted in improvements in cognitive functions. However, the mechanisms underlying the relationship between physical activity and cognition are still poorly understood. Recently, it was shown that acute bouts of exercise resulted in reduced executive control at higher relative exercise intensities. Considering that aging is characterized by a reduction in potential energy ([Formula: see text] max - energy cost of walking), which leads to higher relative walking intensity for the same absolute speed, it could be argued that any intervention aimed at reducing the relative intensity of the locomotive task would improve executive control while walking. The objective of the present study was to determine the effects of a short-term (8 weeks) high-intensity strength and aerobic training program on executive functions (single and dual task) in a cohort of healthy older adults. Fifty-one participants were included and 47 (age, 70.7 ± 5.6) completed the study which compared the effects of three interventions: lower body strength + aerobic training (LBS-A), upper body strength + aerobic training (UBS-A), and gross motor activities (GMA). Training sessions were held 3 times every week. Both physical fitness (aerobic, neuromuscular, and body composition) and cognitive functions (RNG) during a dual task were assessed before and after the intervention. Even though the LBS-A and UBS-A interventions increased potential energy to a higher level (Effect size: LBS-A-moderate, UBS-A-small, GMA-trivial), all groups showed equivalent improvement in cognitive function, with inhibition being more sensitive to the intervention. These findings suggest that different exercise programs targeting physical fitness and/or gross motor skills may lead to equivalent improvement in

  1. Nuclear Structure Studies with the SCANDIUM-45, SAMARIUM-144, and LEAD-208

    NASA Astrophysics Data System (ADS)

    Mostajabodda'Vati, Mojtaba

    Experiments were performed to measure neutron time-of-flight spectra from the (p,n) reaction on ^{45}Sc, ^{144 }Sm, and ^{208}Pb targets at about 136 MeV. In the ^{45}Sc(p,n) ^{45}Ti reaction we observe a 19/2^-, 17/2^- doublet at 4.3 MeV. These states are part of the two-particle, one-hole (pif _sp{7/2}{2}, nuf_sp{7/2}{ -1}) band of states. Distorted Wave Impulse Approximation (DWIA) calculations for these transitions were performed using wave functions obtained from a shell -model calculation which considers five particles in the 1f-2p shell with no restriction. These calculations describe the experimental results well without renormalization. The Gamow-Teller (GT) strength in ^{45 }Sc(p,n)^{45}Ti was considered also; the strength observed in peaks is about 40% of the minimum value expected from the simple GT sum rule. In the ^{144}Sm(p,n) ^{144}Eu reaction we observe a (pih_{11/2 }, nuh_sp {11/2}{-1}) 11^+ , 0 hbaromega stretched state at 2.2 MeV of excitation. A DWIA calculation for this transition with only the simple shell-model wave function needs to be normalized by 0.55 to agree with the experiment. More realistic wave functions were obtained from a 3p-3h shell -model calculation. The DWIA normalization factor required using these wave functions is essentially unity (0.95). The total observed GT strength in peaks is 40% of the GT sum rule value. A single peak is observed to be strongly excited in the ^{208}Pb(p,n) ^{208}Bi reaction at large angles. This peak was interpreted earlier as the (pii _{13/2}, nu i_sp{13/2}{-1} ) 13^+, 0 hbar omega state. The present experiment reveals that the observed peak is too broad to be a single state and that the angular distribution cannot be described well by a DWIA calculation assuming only a single transition. We believe that this peak is a doublet including an ( pii_{13/2}, nui_sp{13/2} {-1}) 11^+ state. This conclusion is supported by a higher resolution measurement performed at a single angle at 99 MeV. Assuming

  2. 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.

  3. 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.

  4. 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

  5. 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

  6. 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.

  7. Strength Training in Individuals with Stroke

    PubMed Central

    Eng, Janice J

    2012-01-01

    Purpose This paper reviews the mechanisms underlying the inability to generate force in individuals with stroke and summarizes the effects of strength training in these individuals. In addition, a systematic review of studies that have incorporated progressive strengthening interventions in individuals with stroke is presented. Summary of Key Points Central (e.g., motor recruitment) and peripheral (e.g., muscle atrophy) sources may alter muscle strength in individuals with stroke and further investigations are needed to partition and quantify their effects. As to the effect of strength training interventions in individuals with stroke, the majority of studies (albeit with small samples) that evaluated muscle strength as an outcome demonstrated improvements. With regard to the effect of strength training on functional outcomes in individuals with stroke, positive outcomes were found in less rigorous pre-test/post-test studies, but more conflicting results with controlled trials. Conclusions Although there is some suggestion that strength training alone can improve muscle strength, further research is required to optimize strength training and the transfer of these strength gains to functional tasks in individuals with stroke. PMID:23255839

  8. Columbia SMA Project: A Randomized, Control Trial of the Effects of Exercise on Motor Function and Strength in Patients with Spinal Muscular Atrophy (SMA)

    DTIC Science & Technology

    2012-06-01

    function in patients with Parkinson’s disease. Neurology. 2003;60:1119-1124 Merlini L, Mazzone ES, Solari A, Morandi L. Reliability of hand-held...The Six Minute Walk Test (6MWT) is a reliable clinical measure of fatigue. Mean power frequency (MPF) and root mean square amplitude (RMS) are

  9. 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.

  10. Wheelchair armrest strength testing.

    PubMed

    Cooper, R A; Rentschler, A J; O'Connor, T J; Ster, J F

    2000-01-01

    There are about 1.4 million manual wheelchair users, 100,000 electric-powered wheelchair users, and 60,000 electric-powered scooter users. The current study was undertaken to determine if the fasteners of a clamp-type armrest receiver were prone to failure. The first test was used to examine the potential misalignment of the armrest receiver components that attach it to the frame. The second test was to evaluate the entire armrest using the American National Standards Institute/Rehabilitation Engineering and Assistive Technology Society of North America armrest static strength standard. Finally, we conducted three fatigue tests. The first fatigue test was performed by repeating the static stability tests multiple times. The last two tests were a modified version of the double-drum wheelchair fatigue test used to apply repeated loading and vibration simultaneously. A paired t-test showed that there is no statistically significant difference (p = 0.08), with a confidence of 95%, between critical alignment measurements. The armrest including the receiver passed the standard requirement of a force of 760 N being applied outward at 15 degrees. During fatigue testing, we found that armrests did not exhibit any visible or functional damage. Upon completion of the tests, the armrests and receivers functioned properly. At about 100,289 cycles on a double-drum test machine, three bolts failed on each armrest receiver when the screws were loosened to have only five threads engaged prior to commencing the test. The design of the armrest tested was in compliance with existing national and international standards. Currently, both International Standards Organization and American National Standards Institute/Rehabilitation Engineering and Assistive Technology Society committees are developing standards for seating systems that will include static, impact, and fatigue strength testing of devices like lateral torso supports, lateral hip support, etc. Methods similar to those

  11. Transitional γ strength in Cd isotopes

    NASA Astrophysics Data System (ADS)

    Larsen, A. C.; Ruud, I. E.; Bürger, A.; Goriely, S.; Guttormsen, M.; Görgen, A.; Hagen, T. W.; Harissopulos, S.; Nyhus, H. T.; Renstrøm, T.; Schiller, A.; Siem, S.; Tveten, G. M.; Voinov, A.; Wiedeking, M.

    2013-01-01

    The level densities and γ-ray strength functions of 105,106,111,112Cd have been extracted from particle-γ coincidence data using the Oslo method. The level densities are in very good agreement with known levels at low excitation energy. The γ-ray strength functions display no strong enhancement for low γ energies. However, more low-energy strength is apparent for 105,106Cd than for 111,112Cd. For γ energies above ≈4 MeV, there is evidence for some extra strength, similar to what has been previously observed for the Sn isotopes. The origin of this extra strength is unclear; it might be due to E1 and M1 transitions originating from neutron skin oscillations or the spin-flip resonance, respectively.

  12. Strength Training and Your Child

    MedlinePlus

    ... Old Feeding Your 1- to 2-Year-Old Strength Training and Your Child KidsHealth > For Parents > Strength ... help prevent injuries and speed up recovery. About Strength Training Strength training is the practice of using ...

  13. 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.

  14. Unified description of the double {beta} decay to the first quadrupole phonon state in spherical and deformed nuclei

    SciTech Connect

    Raduta, C. M.; Raduta, A. A.

    2007-10-15

    The Gamow-Teller transition operator is written as a polynomial in the dipole proton-neutron and quadrupole charge-conserving quasiparticle random-phase approximation boson operators, using the prescription of the boson expansion technique. Then, the 2{nu}{beta}{beta} process ending on the first 2{sup +} state in the daughter nucleus is allowed through one-, two-, and three-boson states describing the odd-odd intermediate nucleus. The approach uses a single particle basis that is obtained by projecting out the good angular momentum from an orthogonal set of deformed functions. The basis for mother and daughter nuclei may have different deformations. The GT transition amplitude as well as the half-lives were calculated for 18 transitions. Results are compared with the available data as well as with the predictions obtained with other methods.

  15. Analysis of the topological properties of the proximal femur on a regional scale: evaluation of multi-detector CT-scans for the assessment of biomechanical strength using local Minkowski functionals in 3D

    NASA Astrophysics Data System (ADS)

    Boehm, H. F.; Link, T. M.; Monetti, R. A.; Kuhn, V.; Eckstein, F.; Raeth, C. W.; Reiser, M.

    2006-03-01

    In our recent studies on the analysis of bone texture in the context of Osteoporosis, we could already demonstrate the great potential of the topological evaluation of bone architecture based on the Minkowski Functionals (MF) in 2D and 3D for the prediction of the mechanical strength of cubic bone specimens depicted by high resolution MRI. Other than before, we now assess the mechanical characteristics of whole hip bone specimens imaged by multi-detector computed tomography. Due to the specific properties of the imaging modality and the bone tissue in the proximal femur, this requires to introduce a new analysis method. The internal architecture of the hip is functionally highly specialized to withstand the complex pattern of external and internal forces associated with human gait. Since the direction, connectivity and distribution of the trabeculae changes considerably within narrow spatial limits it seems most reasonable to evaluate the femoral bone structure on a local scale. The Minkowski functionals are a set of morphological descriptors for the topological characterization of binarized, multi-dimensional, convex objects with respect to shape, structure, and the connectivity of their components. The MF are usually used as global descriptors and may react very sensitively to minor structural variations which presents a major limitation in a number of applications. The objective of this work is to assess the mechanical competence of whole hip bone specimens using parameters based on the MF. We introduce an algorithm that considers the local topological aspects of the bone architecture of the proximal femur allowing to identify regions within the bone that contribute more to the overall mechanical strength than others.

  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 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.

    PubMed

    Lu, Jun-Xia; Burton, Sarah D; Xu, Yimin S; Buchko, Garry W; Shaw, Wendy J

    2014-01-01

    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 K24S28 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, 0.15, 0.2 M), the calcium concentration (0.07 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 Ca(2+) (8:1 [Ca(2+)]:[LRAP-K24S28(+P)]) resulting in a 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 Ca(2+) and in the T21I-mutation. Collectively, these data suggest that phosphorylated LRAP is able to accommodate structural changes while maintaining its interaction with the surface, and provides further evidence of the structural sensitivity of the K24S28 region, a sensitivity that may contribute to function in biomineralization.

  18. 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

  19. 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.

  20. Application of the Minkowski functionals in 3D to high-resolution MR images of trabecular bone: prediction of the biomechanical strength by nonlinear topological measures

    NASA Astrophysics Data System (ADS)

    Boehm, Holger F.; Link, Thomas M.; Monetti, Roberto A.; Mueller, Dirk; Rummeny, Ernst J.; Newitt, David; Majumdar, Sharmila; Raeth, Christoph W.

    2004-05-01

    Multi-dimensional convex objects can be characterized with respect to shape, structure, and the connectivity of their components using a set of morphological descriptors known as the Minkowski functionals. In a 3D Euclidian space, these correspond to volume, surface area, mean integral curvature, and the Euler-Poincaré characteristic. We introduce the Minkowski functionals to medical image processing for the morphological analysis of trabecular bone tissue. In the context of osteoporosis-a metabolic disorder leading to a weakening of bone due to deterioration of micro-architecture-the structure of bone increasingly gains attention in the quantification of bone quality. The trabecular architecture of healthy cancellous bone consists of a complex 3D system of inter-connected mineralised elements whereas in osteoporosis the micro-structure is dominated by gaps and disconnections. At present, the standard parameter for diagnosis and assessment of fracture risk in osteoporosis is the bone mineral density (BMD) - a bulk measure of mineralisation irrespective of structural texture characteristics. With the development of modern imaging modalities (high resolution MRI, micro-CT) with spatial resolutions allowing to depict individual trabeculae bone micro-architecture has successfully been analysed using linear, 2- dimensional structural measures adopted from standard histo-morphometry. The preliminary results of our study demonstrate that due to the complex - i.e. the non-linear - network of trabecular bone structures non-linear measures in 3D are superior to linear ones in predicting mechanical properties of trabecular bone from structural information extracted from high resolution MR image data.

  1. 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.

  2. 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

  3. Strength and Balance Exercises

    MedlinePlus

    ... Venous Thromboembolism Aortic Aneurysm More Strength and Balance Exercises Updated:Sep 8,2016 If you have medical ... if you have been inactive and want to exercise vigorously, check with your doctor before beginning a ...

  4. 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...

  5. Reduction of bone strength

    NASA Technical Reports Server (NTRS)

    Bingham, Cindy

    1990-01-01

    Viewgraphs on reduction of bone strength are presented. WEHI 231 B growth rates, experimental chambers used to apply the electric field to the cell cultures, and a mouse suspended by rotating cuff in electromagnetic field are shown.

  6. Hand-Strength Meter

    NASA Technical Reports Server (NTRS)

    Tcheng, Ping; Elliot, Joe

    1987-01-01

    Special grip-strength meter designed for accurate, reproducible measurement of hand rehabilitation. Four strain gauges connected in Wheatstone bridge to measure deflection caused by gripping hand. Compressive force exerted by hand transmitted to measuring beams. Beams therefore deflected or strained, and mechanical strain sensed by strain gauges and converted into electrical signal. After amplification and conditioning, signal displayed on LED as measure of gripping strength of hand.

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. Strength of inorganic glass

    SciTech Connect

    Kurkjian, C.R.

    1985-01-01

    This book presents information on the following topics: a look at the history of glass strength; atomistic theory of fracture; surface chemistry in relation to the strength and fracture of silicate glasses; high-speed photographic investigations of the dynamic localized loading of some oxide glasses; a correction for measurements of contact area using Newton's rings; envionmentally enhanced crack growth; fatigue in glass; behavior of flaws in fused silica fibers; fracture toughness of chalcogenide glasses and glass-ceramics; fracture analysis of glass surfaces; and fracture mechanics parameters for glasses - a compilation and correlation.

  12. Spin Resonance Strength Calculations

    NASA Astrophysics Data System (ADS)

    Courant, E. D.

    2009-08-01

    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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. Line strengths, collision strengths and excitation rates for multiply-charged silicon ions

    NASA Technical Reports Server (NTRS)

    Davis, J.; Kepple, P. C.; Blaha, M.

    1977-01-01

    In the present paper, the line strengths, collision strengths, and rate coefficients are calculated for a variety of transitions in multiply charged silicon ions from Si(VI) to Si(XIV). The line strengths are obtained by using Clementi wave functions for the ground-state configuration, and excited-state wave functions generated by a semiempirical method. The collision strengths are calculated in an LS coupling scheme in the distorted-wave approximation, neglecting exchange except for the helium-like transitions. These results are then integrated over a Maxwellian velocity distribution function to yield rate coefficients. The rates are presented graphically and also in terms of a two-parameter fit.

  18. 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.

  19. 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.

  20. 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

  1. Oscillator strengths for OII ions

    NASA Technical Reports Server (NTRS)

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

    1983-01-01

    Oscillator strengths between various doublet states of OII ions are calculated in which extensive multi-configuration wave functions are used. The lower levels for the transitions are of the 2p(3) D(2)o and 2p(3) 2po states, and the upper levels are 2p(4), 3s, and 3d states. The results, which are estimated to have errors of less than 10% for individual transitions, agree quite well with the beam foil experiments, as well as with the calculations by use of the non-closed shell many electron theory (NCMET). The agreement with the rocket measurements is also good except for the 538/581 A pair, in which the 538 A line is believed to be blend with the other stronger quartet line. However, a comparison with the recent branching ratio measurement indicates that discrepances between the present calculation and th experiment do exist for certain transistions.

  2. Strength Training: For Overall Fitness

    MedlinePlus

    Healthy Lifestyle Fitness Strength training is an important part of an overall fitness program. Here's what strength training can do for ... is a key component of overall health and fitness for everyone. Lean muscle mass naturally diminishes with ...

  3. 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.

  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. Strength of Rewelded Inconel 718

    NASA Technical Reports Server (NTRS)

    Bayless, E.; Lovoy, C. V.; Mcllwain, M. C.; Munafo, P.

    1982-01-01

    Inconel 718, nickel-based alloy used extensively for high-temperature structural service, welded repeatedly without detriment to its strength. According to NASA report, tests show 12 repairs on same weld joint do not adversely affect ultimate tensile strenth, yield strength, fatigue strength, metallurgical grain structures, or ability of weld joint to respond to post weld heat treatments.

  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. 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.

  10. Factors Contributing to Chronic Ankle Instability: A Strength Perspective

    PubMed Central

    Kaminski, Thomas W.; Hartsell, Heather D.

    2002-01-01

    Objective: To examine the concept of dynamic ankle stability and closely critique the relevant research over the past 50+ years focusing on strength as it relates to those with chronic ankle instability (CAI). Data Sources: We reviewed the literature regarding the assessment of strength related to CAI. We searched MEDLINE and ISI Web of Science from 1950 through 2001 using the key words functional ankle instability, chronic ankle instability, strength, ankle stability, chronic ankle dysfunction, and isokinetics. Data Synthesis: An overview of dynamic stability in the ankle is established, followed by a comprehensive discussion involving the variables used to assess ankle strength. Additionally, a historical look at deficits in muscular stability leading to CAI is provided, and a compilation of numerous contemporary approaches examining strength as it relates to CAI is presented. Conclusions/Recommendations: Although strength is an important consideration during ankle rehabilitation, deficits in ankle strength are not highly correlated with CAI. More contemporary approaches involving the examination of reciprocal muscle-group ratios as a measure of strength have recently been investigated and offer an insightful, albeit different, avenue for future exploration. Evidence pertaining to the effects of strength training on those afflicted with CAI is lacking, including what, if any, implication strength training has on the various measures of ankle strength. PMID:12937561

  11. 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…

  12. The Dependable Strengths Articulation Process: How It Works.

    ERIC Educational Resources Information Center

    Haldane, Bernard Johnson

    Dependable Strengths Articulation Process (DSAP) is a self-development process designed to facilitate positive self-constructions and improved personal functioning through a systematic intervention that enables participants to recognize, articulate, communicate and use their Dependable Strengths. Because it is a peer-assisted process, each…

  13. Fault Roughness Records Strength

    NASA Astrophysics Data System (ADS)

    Brodsky, E. E.; Candela, T.; Kirkpatrick, J. D.

    2014-12-01

    Fault roughness is commonly ~0.1-1% at the outcrop exposure scale. More mature faults are smoother than less mature ones, but the overall range of roughness is surprisingly limited which suggests dynamic control. In addition, the power spectra of many exposed fault surfaces follow a single power law over scales from millimeters to 10's of meters. This is another surprising observation as distinct structures such as slickenlines and mullions are clearly visible on the same surfaces at well-defined scales. We can reconcile both observations by suggesting that the roughness of fault surfaces is controlled by the maximum strain that can be supported elastically in the wallrock. If the fault surface topography requires more than 0.1-1% strain, it fails. Invoking wallrock strength explains two additional observations on the Corona Heights fault for which we have extensive roughness data. Firstly, the surface is isotropic below a scale of 30 microns and has grooves at larger scales. Samples from at least three other faults (Dixie Valley, Mount St. Helens and San Andreas) also are isotropic at scales below 10's of microns. If grooves can only persist when the walls of the grooves have a sufficiently low slope to maintain the shape, this scale of isotropy can be predicted based on the measured slip perpendicular roughness data. The observed 30 micron scale at Corona Heights is consistent with an elastic strain of 0.01 estimated from the observed slip perpendicular roughness with a Hurst exponent of 0.8. The second observation at Corona Heights is that slickenlines are not deflected around meter-scale mullions. Yielding of these mullions at centimeter to meter scale is predicted from the slip parallel roughness as measured here. The success of the strain criterion for Corona Heights supports it as the appropriate control on fault roughness. Micromechanically, the criterion implies that failure of the fault surface is a continual process during slip. Macroscopically, the

  14. When unity makes strength

    PubMed Central

    Messaoudene, Meriem; Avril, Marie-Françoise; Caignard, Anne

    2014-01-01

    In metastatic melanoma patients, circulating natural killer (NK) cells display phenotypic and functional alterations that appear to correlate with the duration of stage IV disease. Moreover, specific NK cell subsets that exhibit robust tumoricidal functions upon activation by cytokines infiltrate the diseased lymph nodes of these patients. These data suggest that NK cells may be harnessed for the development of novel combinatorial immunotherapies against melanoma. PMID:25340005

  15. Airborne field strength monitoring

    NASA Astrophysics Data System (ADS)

    Bredemeyer, J.; Kleine-Ostmann, T.; Schrader, T.; Münter, K.; Ritter, J.

    2007-06-01

    In civil and military aviation, ground based navigation aids (NAVAIDS) are still crucial for flight guidance even though the acceptance of satellite based systems (GNSS) increases. Part of the calibration process for NAVAIDS (ILS, DME, VOR) is to perform a flight inspection according to specified methods as stated in a document (DOC8071, 2000) by the International Civil Aviation Organization (ICAO). One major task is to determine the coverage, or, in other words, the true signal-in-space field strength of a ground transmitter. This has always been a challenge to flight inspection up to now, since, especially in the L-band (DME, 1GHz), the antenna installed performance was known with an uncertainty of 10 dB or even more. In order to meet ICAO's required accuracy of ±3 dB it is necessary to have a precise 3-D antenna factor of the receiving antenna operating on the airborne platform including all losses and impedance mismatching. Introducing precise, effective antenna factors to flight inspection to achieve the required accuracy is new and not published in relevant papers yet. The authors try to establish a new balanced procedure between simulation and validation by airborne and ground measurements. This involves the interpretation of measured scattering parameters gained both on the ground and airborne in comparison with numerical results obtained by the multilevel fast multipole algorithm (MLFMA) accelerated method of moments (MoM) using a complex geometric model of the aircraft. First results will be presented in this paper.

  16. 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.

  17. On the strength of glasses

    PubMed Central

    Wisitsorasak, Apiwat; Wolynes, Peter G.

    2012-01-01

    The remarkable strength of glasses is examined using the random first order transition theory of the glass transition. The theory predicts that strength depends on elastic modulus but also on the configurational energy frozen in when the glass is prepared. The stress catalysis of cooperative rearrangements of the type responsible for the supercooled liquid’s high viscosity account quantitatively for the measured strength of a range of metallic glasses, silica, and a polymer glass. PMID:22988070

  18. 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…

  19. Inspiratory muscle strength in chronic obstructive pulmonary disease.

    PubMed

    Larson, Janet L; Covey, Margaret K; Corbridge, Susan

    2002-05-01

    Chronic obstructive pulmonary disease is associated with a functional weakness of the inspiratory muscles. Multiple factors contribute to the decline in functional strength including hyperinflation of the chest, deterioration in nutritional status, and the indirect effects of an exacerbation. The decreased inspiratory muscle strength contributes to sensations of dyspnea and places individuals at risk for respiratory muscle fatigue. The worsening dyspnea causes individuals to reduce their physical activities and ultimately become physically deconditioned. Maximal inspiratory pressure is commonly used to measure functional strength of the inspiratory muscles, and interventions to minimize the extent of decline include inspiratory muscle training, aerobic exercise training, nutritional supplementation, and methods to prevent exacerbations. In the critical care unit, multiple comorbid conditions contribute to further decline in inspiratory muscle strength, making it important to assess respiratory muscle function regularly.

  20. 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.

  1. Aluminum alloys with improved strength

    NASA Technical Reports Server (NTRS)

    Deiasi, R.; Adler, P.

    1975-01-01

    Mechanical strength and stress corrosion of new BAR and 7050 alloys that include Zn instead of Cr have been studied and compared with those of 7075 aluminum alloy. Added mechanical strength of new alloys is attributed to finer grain size of 5 to 8 micrometers, however, susceptibility to stress corrosion attack is increased.

  2. 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…

  3. Breit-Pauli oscillator strengths and electron excitation collision strengths for Si VIII

    NASA Astrophysics Data System (ADS)

    Tayal, S. S.

    2012-05-01

    Aims: Oscillator strengths and electron impact excitation collision strengths for transitions between the 68 fine-structure levels of the 2s22p3, 2s2p4, 2p5, 2s22p23s, 2s22p23p, 2s22p23d and 2s2p33s configurations in Si VIII are calculated. Thermally averaged collision strengths are presented as a function of electron temperature for application to solar and other astrophysical plasmas. Methods: The collision strengths have been calculated using the B-splineBreit-Pauli R-matrixmethod for allowed and forbidden transitions in Si VIII. The relativistic effects have been incorporated through mass, Darwin and spin-orbit one-body operators in the Breit-Pauli Hamiltonian in the scattering calculation, while in the calculation of oscillator strengths the one-body and two-body relativistic operators are included. Flexible non-orthogonal sets of spectroscopic and correlation radial functions are used to obtain accurate description of Si VIII levels and to represent the scattering functions. The 68 fine-structure levels of the 2s22p3, 2s2p4, 2p5, 2s22p23s, 2s22p23p, 2s22p23d and 2s2p33s configurations have been considered in both the radiative and scattering calculations. The present scattering calculations are more extensive than previous ones, leading to a total 2278 transitions between fine-structure levels. Results: The calculated excitation energies are in excellent agreement with experiment and represent an improvement over the previous calculations. The present collision strengths show reasonable agreement with the previously available R-matrix and distorted-wave calculations. The oscillator strengths for E1 transitions normally compare very well with previous calculations. The effective collision strengths are obtained by integrating total resonant and non-resonant collision strengths over a Maxwellian distribution of electron energies and these are presented over a wide temperature range from 104 to 4.0 × 106 K. Tables 1-4 are only available in electronic form at

  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. Tensile strength of bovine trabecular bone.

    PubMed

    Kaplan, S J; Hayes, W C; Stone, J L; Beaupré, G S

    1985-01-01

    Data on the tensile and compressive properties of trabecular bone are needed to define input parameters and failure criteria for modeling total joint replacements. To help resolve differences in reports comparing tensile and compressive properties of trabecular bone, we have developed new methods, based on porous foam technology, for tensile testing of fresh/frozen trabecular bone specimens. Using bovine trabecular bone from an isotropic region from the proximal humerus as a model material, we measured ultimate strengths in tension and compression for two groups of 24 specimens each. The average ultimate strength in tension was 7.6 +/- 2.2 (95% C.I.) MPa and in compression was 12.4 +/- 3.2 MPa. This difference was statistically significant (p = 0.013) and was not related to density differences between the test groups (p = 0.28). Strength was related by a power-law function of the local apparent density, but, even accounting for density influences, isotropic bovine trabecular bone exhibits significantly lower strengths in tension than in compression.

  6. Tensile Strength of Carbon/Carbon Composites

    NASA Astrophysics Data System (ADS)

    Hatta, Hiroshi; Aoi, Tatsuji; Kawahara, Itaru; Kogo, Yasuo; Shiota, Ichiro

    In order to identify ruling mechanisms of tensile fracture of Carbon/Carbon composites (C/Cs), tensile tests were carried out for various C/Cs as functions of the density, heat treatment temperature, and interfacial strength between fiber and matrix. Three processing routes of preformed yarn, resin char, and HIP processes were adopted to densify C/Cs. These C/Cs were finally heat-treated at temperatures from 2273K to 3300K. The interfacial strength between fiber and matrix was varied by the selection of processing routes. As a result, two ruling failure mechanisms were identified. At density lower than 1.6g/cm3, the tensile fracture was controlled by stress transfer capability from the matrix to reinforcing fibers. However, at higher density than 1.6g/cm3, tensile strength was primarily governed by the interfacial strength between the matrix and fibers. Thus the latter mechanism is nearly same as ceramic matrix composites.

  7. Stochastic models for the tensile strength, fatigue

    NASA Technical Reports Server (NTRS)

    Phoenix, S. L.

    1976-01-01

    The time-to-failure of a single fiber is modeled as a functional of the fiber load history and reasonable forms for this functional are proposed. Earlier models by Daniels and Coleman are shown to be special cases of the proposed model and apparent disparities in their behavior are discussed. Techniques are presented for determining analytically the asymptotic distributions of the tensile strength and time-to-failure for bundles of a large number of fibers. For smaller bundles, exact results are far too cumbersome to be of use so that efficient Monte Carlo simulation procedures are proposed.

  8. 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

  9. 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.

  10. 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%.

  11. 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%.

  12. 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.

  13. Experimental study of radiative pion capture on /sup 13/C, /sup 20/Ne, /sup 90/Zr, /sup 19/F and /sup 12/C

    SciTech Connect

    Martoff, C.J.

    1980-11-01

    Photon spectra for 50 < E/sub ..gamma../ < 135 MeV have been measured from the radiative capture of stopped negative pions by the nuclides /sup 13/C, /sup 19/F, /sup 20/Ne, and /sup 90/Zr. The e/sup +/e/sup -/ pair spectrometer system used has resolution 850 keV fwhm and photon detection efficiency 5 x 10/sup -6/. The total radiative capture branching ratios measured are /sup 13/C (1.66 +- 0.25)%, /sup 19/F (2.40 +- 0.48)%, /sup 20/Ne (1.60 +- 0.24)%, and /sup 90/Zr (2.1 +- 0.5)%. The partial radiative capture branching ratios to four bound states and two resonances in /sup 20/F, and two bound states and three resonances in /sup 13/B have also been measured. The branching ratio for /sup 13/C(..pi../sup -/,..gamma..)/sup 13/B g.s. is (6.1 +- 1.2) x 10/sup -4/. Comparison of this result with the beta decay rate of /sup 13/B shows that (84 +- 16)% of the pion capture amplitude is accounted for by the Gamow-Teller matrix element. Further analysis suggests that much of the remaining strength is E2. The measured branching ratios to resonant states in /sup 13/C(..pi../sup -/,..gamma..)/sup 13/B are shown to be in agreement with detailed shell model calculations. The total single-particle strength in these transitions is shown to be approximately half as large as that of the T = 3/2 part of the E1 photoresonance (the Giant Dipole Resonance) in /sup 13/C. The branching ratio for /sup 20/Ne(..pi../sup -/,..gamma..)/sup 20/F (T = 1, J/sup ..pi../ = 1/sup +/, E/sub x/ = 1.06 MeV) is 0.91 +- 0.52).10/sup -4/. Comparison with the electroexcitation of the analog giant M1 state in /sup 20/Ne (11.24 MeV) shows that the M1 transition amplitude is less than (46 +- 14)% Gamow-Teller. This result is in agreement with detailed shell model calculations of the M1 transition. The photon spectrum for radiative pion capture from flight (reaction /sup 12/C(..pi../sup +/ T = 44 MeV, ..gamma.. at 90/sup 0/)) has been measured. 13 figures, 12 tables.

  14. 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.

  15. Strength Training and Your Child

    MedlinePlus

    ... considering strength-training programs: An instructor-to-child ratio of no more than 1 to 10. The ... major muscle groups of the upper and lower body and core. Kids should start with no load ( ...

  16. 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.

  17. Machine Gun Liner Bond Strength

    DTIC Science & Technology

    2007-08-01

    investigation does not constitute a complete analysis of liner failures in the M2 machine gun. The fact that two different liner-failure modes were...An order-of-magnitude estimate can be made of the bond strength in this case using a standard elastic analysis and some reasonable assumptions... analysis of the forces on the machine gun bullet, it was found that the measured bond strength was adequate to resist the reaction forces produced when

  18. 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.

  19. 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.

  20. Strength distributions of adhesive bonded and adhesive/rivet combined joints

    NASA Astrophysics Data System (ADS)

    Imanaka, Makoto; Haraga, Kosuke; Nishikawa, Tetsuya

    1992-11-01

    The tensile and shear strengths of adhesive and adhesive/rivet combined joints are statistically evaluated, and the probability of failure is calculated for these two types of joints. Attention is given to the effects of the adhesive/rivet combination on mean tensile shear strength and coefficient of variation. The adhesive joint's strength distribution was well approximated by Weibull or doubly-exponential distribution function; tensile shear strength is significantly improved by the combination with rivets.

  1. 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.

  2. Strength of a bifurcated H bond.

    PubMed

    Feldblum, Esther S; Arkin, Isaiah T

    2014-03-18

    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 (13)C=(18)O 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.

  3. Post impact compressive strength in composites

    NASA Technical Reports Server (NTRS)

    Demuts, Edvins; Sandhu, Raghbir S.; Daniels, John A.

    1992-01-01

    Presented in this paper are the plan, equipment, procedures, and findings of an experimental investigation of the tolerance to low velocity impact of a graphite epoxy (AS4/3501-6) and graphite bismaleimide (M6/CYCOM3100) advanced composites. The applied impacts were governed by the Air Force Guide Specification 87221. Specimens of each material system having a common nominal layup (10% 0 deg; 80% +/-45 deg; 10% 90 deg), a common 7 inch (17.78 cm) by 10 inch (25.40 cm) size, five different thicknesses (9, 26, 48, 74, and 96 plies), and ambient moisture content were impacted and strength tested at room temperature. Damaged areas and post impact compression strengths (PICS) were among the most significant findings obtained. While the undamaged per ply compression strength of both materials is a strong function of laminate thickness, the per ply PICS is not. The average difference in per ply PICS between the two material systems is about seven percent. Although a smaller percentage of the applied kinetic energy was absorbed by the Gr/BMI than by the Gr/Epoxy composites, larger damaged areas were produced in the Gr/BMI than in Gr/Epoxy. Within the limitations of this investigation, the Gr/BMI system seems to offer no advantage in damage tolerance over the Gr/Epoxy system examined.

  4. Postsurgical shoulder strength in the older patient.

    PubMed

    Hartsell, H D

    1993-12-01

    Following surgery, a goal of rehabilitation is to return the surgical extremity to its original strength. However, for the older rotator cuff repair patient, we are unsure if this is a realistic goal. The purpose of this study was to determine the quality of shoulder strength in older males who had undergone rotator cuff repair and acromioplasty surgery and to determine if test position and test velocity effects for rotation at the shoulder existed. Nine patients (mean age = 60.8 years) were tested bilaterally on the Cybex II isokinetic dynamometer for two movements (internal/external rotation), two velocities (60 degrees/sec, 120 degrees/sec), and two positions (neutral, 90 degrees abduction) to determine the peak torques for the shoulders. Following a three-way analysis of variance (ANOVA) with repeated measures, results indicated that the surgical shoulder had torque values approximating the nonsurgical shoulder and that test position had no significant effect on the internal or external rotation torques produced. As seen with nonshoulder-impaired younger subjects, peak torque decreased with increased test velocities. It was concluded that the older rotator cuff repair patient may be expected to attain a level of strength in the surgical shoulder similar to or exceeding the nonsurgical shoulder and that either test position recommended by Cybex for testing of the shoulder rotators was acceptable. Clinically, a full functional recovery similar to the nonsurgical shoulder should be expected in the older patient with postsurgical rotator cuff repair and acromioplasty.

  5. Correlation of Chlorite Frictional Strength with Composition

    NASA Astrophysics Data System (ADS)

    Moore, D. E.; Lockner, D. A.

    2015-12-01

    Chlorite is a common phyllosilicate mineral in crustal fault zones, and it is generally considered to contribute to fault-zone weakening. However, very little is known about its frictional properties, in part because of the difficulty in obtaining suitable material for study. Synthetic gouges (<90 μm grain size) have been prepared from four chlorite-rich separates whose compositions range between 18.3 and 33.6 wt% MgO, 1.3-21.6 wt% FeO (total Fe content), and 25.0-33.0 wt% SiO2 (electron microprobe analysis). Magnesium contents vary directly with Si and inversely with Fe. Frictional strengths were measured in the temperature range 25-300°C and shearing rates between 0.00115 and 1.15 μm/s, with fluid pressure and effective normal stress held constant at 60 and 100 MPa, respectively. The chlorites are velocity strengthening at all tested conditions, promoting stable slip. No obvious trends in strength relative to either temperature or velocity were discernible for a given chlorite. In contrast, the frictional strength at any given set of physical conditions is a function of chlorite composition, the most Fe-rich chlorite being the strongest (coefficient of friction, μ in the range 0.26-0.36) and the most Mg- and Si-rich sample the weakest (μ = 0.16-0.22). This is one of the first reports of a compositional influence on the frictional properties of a mineral. The results confirm that chlorite will contribute to strength reduction in fault gouge, but the Mg-rich chlorites associated with ultramafic rocks will be more effective weakening agents than the relatively high-Fe chlorites more typical of quartzofeldspathic crustal rocks.

  6. Topological strength of magnetic skyrmions

    NASA Astrophysics Data System (ADS)

    Bazeia, D.; Ramos, J. G. G. S.; Rodrigues, E. I. B.

    2017-02-01

    This work deals with magnetic structures that attain integer and half-integer skyrmion numbers. We model and solve the problem analytically, and show how the solutions appear in materials that engender distinct, very specific physical properties, and use them to describe their topological features. In particular, we found a way to model skyrmion with a large transition region correlated with the presence of a two-peak skyrmion number density. Moreover, we run into the issue concerning the topological strength of a vortex-like structure and suggest an experimental realization, important to decide how to modify and measure the topological strength of the magnetic structure.

  7. Efficacy of tibolone and raloxifene for the maintenance of skeletal muscle strength, bone mineral density, balance, body composition, cognitive function, mood/depression, anxiety and quality of life/well-being in late postmenopausal women ≥ 70 years: Study design of a randomized, double-blind, double-dummy, placebo-controlled, single-center trial

    PubMed Central

    Jacobsen, Didy E; Samson, Monique M; Schouw, Yvonne T van der; Grobbee, Diederick E; Verhaar, Harald JJ

    2008-01-01

    Background Postmenopausal women are prone to develop functional disabilities as a result of reduction in muscle strength and muscle mass caused by diminished levels of female sex hormones. While hormone replacement therapy may counteract these changes, conventional hormone replacement therapy is associated with potential harmful effects, such as an increased risk of breast cancer, and its prescription is not recommended. For this reason newer alternative drugs, such as tibolone, a synthetic steroid with estrogenic, progestogenic and androgenic activity, and raloxifene, a selective estrogen receptor modulator, may be more appropriate. This trial investigates the effect of tibolone and raloxifene on muscle strength. Methods We recruited 318 elderly women in our single-center randomized, double-blind, double-dummy, placebo-controlled trial. Participants were randomized to tibolone 1.25 mg (Org OD 14, Organon NV, the Netherlands) plus placebo, raloxifene 60 mg (Evista®, Eli Lilly, United States) plus placebo or two placebo tablets daily for 24 months. The primary aim is to determine if there is a difference between tibolone and placebo or if there is a difference between raloxifene and placebo. Primary endpoints are muscle strength and bone mineral density. The secondary endpoints are postural balance, body composition, cognitive function, anxiety, mood and quality of life. The secondary aim is to determine if there is a difference between tibolone and raloxifene. The measure of effect is the change from the baseline visit to the visits after 3 months, 6 months, 12 months, and 24 months. A follow-up measurement is planned at 30 months to determine whether any effects are sustained after cessation of the study. By December 2007 the blind will be broken and the data analyzed. Trial registration number NTR: 1232 PMID:18533987

  8. Explosive Strength Imbalances in Professional Basketball Players

    PubMed Central

    Schiltz, Marc; Lehance, Cédric; Maquet, Didier; Bury, Thierry; Crielaard, Jean-Michel; Croisier, Jean-Louis

    2009-01-01

    Context: Despite the high rate of lower limb injuries in basketball players, studies of the dominant-limb effect in elite athletes often neglect injury history. Objective: To determine lower limb explosive-strength asymmetries in professional basketball players compared with junior basketball players and control participants. Design: Cohort study. Setting: Academic medical institution. Patients or Other Participants: 15 professional basketball players, 10 junior basketball players, and 20 healthy men. Main Outcome Measure(s): We performed an isokinetic examination to evaluate the knee extensor (Ext) and flexor (Fl) concentric peak torque at 60°·s−1 and 240°·s−1 and (Fl only) eccentric peak torque at 30°·s−1 and 120°·s−1. Functional evaluation included countermovement jump, countermovement jump with arms, 10-m sprint, single-leg drop jump, and single-leg, 10-second continuous jumping. Variables were compared among groups using analysis of variance or a generalized linear mixed model for bilateral variables. Results: The 2 groups of basketball players demonstrated better isokinetic and functional performances than the control group did. No differences in functional or relative isokinetic variables were noted between professional and junior basketball players. Professional players with a history of knee injury failed to reach normal knee extensor strength at 60°·s−1. Knee Ext (60°·s−1) and Fl (eccentric 120°·s−1) torque values as well as 10-second continuous jumping scores were higher in those professional players without a history of knee injury than those with such a history. Compared with the group without a history of knee injury, the group with a history of knee injury maintained leg asymmetry ratios greater than 10% for almost all isokinetic variables and more than 15% for unilateral functional variables. Conclusions: The relative isokinetic and functional performances of professional basketball players were similar to those of junior

  9. 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

  10. 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.

  11. 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.

  12. β -decay rate of 59Fe in shell burning environment and its influence on the production of 60Fe in a massive star

    NASA Astrophysics Data System (ADS)

    Li, K. A.; Lam, Y. H.; Qi, C.; Tang, X. D.; Zhang, N. T.

    2016-12-01

    We deduced the stellar β -decay rate of 59Fe at typical carbon-shell burning temperature by taking the experimental Gamow-Teller transition strengths of the 59Fe excited states. The result is also compared with those derived from large-scale shell model calculations. The new rate is up to a factor of 2.5 lower than the theoretical rate of Fuller, Fowler, and Newman (FFN) and up to a factor of 5 higher than decay rate of Langanke and Martínez-Pinedo (LMP) in the temperature region 0.5 ≤T ≤2 GK. We estimated the impact of the newly determined rate on the synthesis of cosmic γ emitter 60Fe in C-shell burning and explosive C/Ne burning using a one-zone model calculation. Our results show that 59Fe stellar β decay plays an important role in 60Fe nucleosynthesis, even though the uncertainty of the decay rate is rather large due to the error of B (GT) strengths.

  13. 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.

  14. 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.

  15. 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.

  16. Modeling of Sylgard Adhesive Strength

    SciTech Connect

    Stevens, Ralph Robert

    2015-02-03

    Sylgard is the name of a silicone elastomeric potting material manufactured by Dow Corning Corporation.1 Although the manufacturer cites its low adhesive strength as a feature of this product, thin layers of Sylgard do in fact have a non-negligible strength, which has been measured in recent tensile and shear debonding tests. The adhesive strength of thin layers of Sylgard potting material can be important in applications in which components having signi cantly di erent thermal expansion properties are potted together, and the potted assembly is subjected to temperature changes. The tensile and shear tractions developed on the potted surfaces of the components can cause signi cant internal stresses, particularly for components made of low-strength materials with a high area-to-volume ratio. This report is organized as follows: recent Sylgard debonding tests are rst brie y summarized, with particular attention to the adhesion between Sylgard and PBX 9501, and also between Sylgard and aluminum. Next, the type of numerical model that will be used to simulate the debonding behavior exhibited in these tests is described. Then the calibration of the debonding model will be illustrated. Finally, the method by which the model parameters are adjusted (scaled) to be applicable to other, non- tested bond thicknesses is summarized, and all parameters of the model (scaled and unscaled) are presented so that other investigators can reproduce all of the simulations described in this report as well as simulations of the application of interest.

  17. A multiscale strength model for extreme loading conditions

    NASA Astrophysics Data System (ADS)

    Barton, N. R.; Bernier, J. V.; Becker, R.; Arsenlis, A.; Cavallo, R.; Marian, J.; Rhee, M.; Park, H.-S.; Remington, B. A.; Olson, R. T.

    2011-04-01

    We present a multiscale strength model in which strength depends on pressure, strain rate, temperature, and evolving dislocation density. Model construction employs an information passing paradigm to span from the atomistic level to the continuum level. Simulation methods in the overall hierarchy include density functional theory, molecular statics, molecular dynamics, dislocation dynamics, and continuum based approaches. Given the nature of the subcontinuum simulations upon which the strength model is based, the model is particularly appropriate to strain rates in excess of 104 s-1. Strength model parameters are obtained entirely from the hierarchy of simulation methods to obtain a full strength model in a range of loading conditions that so far has been inaccessible to direct measurement of material strength. Model predictions compare favorably with relevant high energy density physics (HEDP) experiments that have bearing on material strength. The model is used to provide insight into HEDP experimental observations and to make predictions of what might be observable using dynamic x-ray diffraction based experimental methods.

  18. 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.

  19. 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

  20. Tongue Strength is Associated with Grip Strength and Nutritional Status in Older Adult Inpatients of a Rehabilitation Hospital.

    PubMed

    Sakai, Kotomi; Nakayama, Enri; Tohara, Haruka; Maeda, Tomomi; Sugimoto, Motonobu; Takehisa, Takahiro; Takehisa, Yozo; Ueda, Koichiro

    2017-04-01

    The aim of this cross-sectional study was to investigate whether tongue strength observed in older adult inpatients of a rehabilitation hospital is associated with muscle function, nutritional status, and dysphagia. A total of 174 older adult inpatients aged 65 years and older in rehabilitation (64 men, 110 women; median age, 84 years; interquartile range, 80-89 years) who were suspected of having reduced tongue strength due to sarcopenia were included in this study. Isometric tongue strength was measured using a device fitted with a disposable oral balloon probe. We evaluated age, muscle function as assessed by the Barthel index and grip strength, nutritional status as measured by the Mini Nutritional Assessment-short form (MNA-SF), body mass index, serum albumin, controlling nutritional status, and calf circumference and arm muscle area to assess muscle mass. In addition, the functional oral intake scale (FOIS) was used as an index of dysphagia. Multivariate linear regression analysis revealed that isometric tongue strength was independently associated with grip strength (coefficient = 0.33, 95 % confidence interval (CI) 0.12-0.54, p = 0.002), MNA-SF (coefficient = 0.74, 95 % CI 0.12-1.35, p = 0.019), and FOIS (coefficient = 0.02, 95 % CI 0.00-0.15, p = 0.047). To maintain and improve tongue strength in association with sarcopenic dysphagia, exercise therapy and nutritional therapy interventions, as well as direct interventions to address tongue strength, may be effective in dysphagia rehabilitation in older adult inpatients.

  1. 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

  2. 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…

  3. 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.

  4. 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.

  5. Fracture strength and adhesive strength of hydroxyapatite-filled polycaprolactone.

    PubMed

    Wong, Shing-Chung; Baji, Avinash

    2008-02-01

    Fracture toughness and tear strength of hydroxyapatite (HAP)-filled poly(epsilon-caprolactone) (PCL) with increasing HAP concentration were studied. The toughness was assessed in terms of essential work of fracture (EWF). Adhesive strength between HAP and PCL interfaces was evaluated using T-peel testing. The adhesion between the two components was found to be relatively strong. Double edge notched tension (DENT) and trousers test specimens were used for the EWF tests. The effect of HAP phase in PCL on the fracture and tearing toughness was investigated. The results obtained from the EWF tests for the HAP-filled PCL complied with the validity criteria of the EWF concept, namely, (1) geometric similarity for all ligament lengths; (2) fully yielded ligament and (3) plane-stress fracture condition. Values for specific essential work of fracture (w ( e )) and specific plastic work of fracture (betaw ( p )) were found to decrease with increase in HAP concentration. The testing procedure showed promise in quantifying the tearing resistance and rising R-curve behavior common in natural materials and it can be extended to other biomaterials that exhibit post-yield deformation. A quantitative assessment based on fracture mechanics of the adhesive strength between the bioactive interfaces plays an important role for continued development of tissue replacement and tissue regeneration materials.

  6. 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

  7. Shear Strength of Aluminum Oxynitride

    NASA Astrophysics Data System (ADS)

    Dandekar, Dattatraya P.; Vaughan, Brian A. M.; Proud, William G.

    2007-06-01

    Aluminum oxynitride (AlON) is a transparent, polycrystalline cubic spinel. The results of investigations^1-4 on shock response of AlON permit determination of the equation of state, and shear strength retained under shock compression. Whereas the values of the HEL of AlON holds no surprises, the inelastic response of AlON reported in Ref. 1-4 differ significantly and is stress dependent. The results of Ref. 1-2 show that AlON retains a shear strength of 3 to 4 GPa when shocked up to around 20 GPa, but the results of Ref, 3-4 seem to suggest a possible loss of shear strength when shocked to 16 GPa and beyond. Our analysis examines the observed differences in the inelastic response of AlON reported in these four studies . 1. J. U. Cazamias, et. al., in Fundamental Issues and Applications of Shock-Wave and High Strain Rate Phenomena, Eds. Staudhammer, Murr, and Meyers, Elsevier, NY, 173 (2001). 2. B. A. M. Vaughn, et.al., Shock Physics, Cavendish Laboratory, Report SP/1092 (2001) 3. T. Sekine, et.al., J. Appl. Phys. 94, 4803 (2003). 4. T. F. Thornhill, et.al., Shock Compression of Matter-2005, Eds. Furnish, Elert, Russell, White, AIP, NY, 143 (2006).

  8. Relationship between tongue strength and 1-year life expectancy in elderly people needing nursing care.

    PubMed

    Yajima, Yuri; Kikutani, Takeshi; Tamura, Fumiyo; Yoshida, Mitsuyoshi

    2017-01-05

    Tongue strength is a useful indicator of oral function and has been found to decrease with aging and reduced physical functioning. The present study aimed to assess the relationships of tongue strength with physical function, mental function, and nutritional status, and also between these factors and 1-year outcomes, to determine whether tongue strength is related to life expectancy in elderly people needing nursing care. The subjects were 140 elderly individuals requiring needing nursing care (49 men and 91 women; ≥65 years). The investigated items included sex, age, activities of daily living (ADL), comorbidity, cognitive function, nutritional status, eating function, occlusal support, and tongue strength. Furthermore, a follow-up study was conducted 1 year later, and factors related to death were identified. The mean tongue strength of the total 140 subjects was 20.3 ± 8.6 kPa. Tongue strength was assessed relative to each of the investigated items, using the t test and one-way analysis of variance. Tongue strength was significantly related to ADL, comorbidity, cognitive function, calf circumference, food intake, and occlusal support. Fifteen subjects were found to have died at the 1-year follow-up study. We assessed the relationships of 1-year outcomes with each of the factors examined, and 1-year outcomes were found to be significantly related to ADL and tongue strength.

  9. 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.

  10. Shell Model Description of the C14 Dating β Decay with Brown-Rho-Scaled NN Interactions

    NASA Astrophysics Data System (ADS)

    Holt, J. W.; Brown, G. E.; Kuo, T. T. S.; Holt, J. D.; Machleidt, R.

    2008-02-01

    We present shell model calculations for the beta decay of C14 to the N14 ground state, treating the states of the A=14 multiplet as two 0p holes in an O16 core. We employ low-momentum nucleon-nucleon (NN) interactions derived from the realistic Bonn-B potential and find that the Gamow-Teller (GT) matrix element is too large to describe the known lifetime. By using a modified version of this potential that incorporates the effects of Brown-Rho scaling medium modifications, we find that the GT matrix element vanishes for a nuclear density around 85% that of nuclear matter. We find that the splitting between the (Jπ,T)=(1+,0) and (Jπ,T)=(0+,1) states in N14 is improved using the medium-modified Bonn-B potential and that the transition strengths from excited states of C14 to the N14 ground state are compatible with recent experiments.

  11. Charge-exchange reactions and nuclear matrix elements for {beta}{beta} decay

    SciTech Connect

    Frekers, D.

    2009-11-09

    Charge-exchange reactions of (n, p) and (p, n) type at intermediate energies are a powerful tool for the study of nuclear matrix element in {beta}{beta} decay. The present paper reviews some of the most recent experiments in this context. Here, the (n, p) type reactions are realized through (d, {sup 2}He), where {sup 2}He refers to two protons in a singlet {sup 1}S{sub 0} state and where both of these are momentum analyzed and detected by the same spectrometer and detector. These reactions have been developed and performed exclusively at KVI, Groningen (NL), using an incident deuteron energy of 183 MeV. Final state resolutions of about 100 keV have routinely been available. On the other hand, the ({sup 3}He, t) reaction is of (p, n) type and was developed at the RCNP facility in Osaka (JP). Measurements with an unprecedented high resolution of 30 keV at incident energies of 420 MeV are now readily possible. Using both reaction types one can extract the Gamow-Teller transition strengths B(GT{sup +}) and B(GT{sup -}), which define the two ''legs'' of the {beta}{beta} decay matrix elements for the 2v{beta}{beta} decay The high resolution available in both reactions allows a detailed insight into the excitations of the intermediate odd-odd nuclei and, as will be shown, some unexpected features are being unveiled.

  12. 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.

  13. Spin-isospin transitions in chromium isotopes within the quasiparticle random phase approximation

    NASA Astrophysics Data System (ADS)

    Cakmak, Sadiye; Nabi, Jameel-Un; Babacan, Tahsin; Maras, Ismail

    2015-01-01

    Beta decay and electron capture on isotopes of chromium are advocated to play a key role in the stellar evolution process. In this paper we endeavor to study charge-changing transitions for 24 isotopes of chromium (42-65Cr). These include neutron-rich and neutron-deficient isotopes of chromium. Three different models from the QRPA genre, namely the pn-QRPA, the Pyatov method (PM) and the Schematic model (SM), were selected to calculate and study the Gamow-Teller (GT) transitions in chromium isotopes. The SM was employed separately in the particle-particle (pp) and pp + particle-hole (ph) channels. To study the effect of deformation, the SM was first used assuming the nuclei to be spherical and later to be deformed. The PM was used both in pp and pp + ph channels but only for the case of spherical nuclei. The pn-QRPA calculation was done by considering both pp and ph forces and taking deformation of nucleus into consideration. A recent study proved this version of pn-QRPA to be the best for calculation of GT strength distributions amongst the QRPA models. The pn-QRPA model calculated GT distributions had low-lying centroids and small widths as compared to other QRPA models. Our calculation results were also compared with other theoretical models and measurements wherever available. Our results are in decent agreement with previous measurements and shell model calculations.

  14. Nuclear structure and weak rates of heavy waiting point nuclei under rp-process conditions

    NASA Astrophysics Data System (ADS)

    Nabi, Jameel-Un; Böyükata, Mahmut

    2017-01-01

    The structure and the weak interaction mediated rates of the heavy waiting point (WP) nuclei 80Zr, 84Mo, 88Ru, 92Pd and 96Cd along N = Z line were studied within the interacting boson model-1 (IBM-1) and the proton-neutron quasi-particle random phase approximation (pn-QRPA). The energy levels of the N = Z WP nuclei were calculated by fitting the essential parameters of IBM-1 Hamiltonian and their geometric shapes were predicted by plotting potential energy surfaces (PESs). Half-lives, continuum electron capture rates, positron decay rates, electron capture cross sections of WP nuclei, energy rates of β-delayed protons and their emission probabilities were later calculated using the pn-QRPA. The calculated Gamow-Teller strength distributions were compared with previous calculation. We present positron decay and continuum electron capture rates on these WP nuclei under rp-process conditions using the same model. For the rp-process conditions, the calculated total weak rates are twice the Skyrme HF+BCS+QRPA rates for 80Zr. For remaining nuclei the two calculations compare well. The electron capture rates are significant and compete well with the corresponding positron decay rates under rp-process conditions. The finding of the present study supports that electron capture rates form an integral part of the weak rates under rp-process conditions and has an important role for the nuclear model calculations.

  15. Decay spectroscopy of N < Z nuclei around 100Sn

    NASA Astrophysics Data System (ADS)

    Park, Joochun (Jason); Eurica Collaboration

    2016-09-01

    Many interesting topics in both nuclear structure and nuclear astrophysics converge on the doubly-magic nucleus 100Sn and nuclei in its vicinity. Among them are the boundaries of proton dripline, the effect of pn interaction in self-conjugate nuclei, and the decay properties required for rp -process calculations in nucleosynthesis models. Despite many studies, experimental knowledge of these nuclides has remained scarce due to low production cross sections and a lack of intense beams. However, record quantities of exotic N = Z isotopes around 100Sn were produced at RIKEN Radioactive Isotope Beam Factory, via fragmentation of a 124Xe beam on a thin 9Be target. Based on the obtained data, 89Rh and 93Ag have been confirmed to be proton unbound. Half-lives of isotopes near the proton dripline will be presented with improved precision compared to literature values. In addition, strategies to determine Qβ for ft values, and consequently the Fermi/Gamow-Teller transition strengths of these isotope decays will be discussed. Work supported by the Natural Sciences and Engineering Research Council of Canada and the National Research Council of Canada.

  16. 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.

  17. 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.

  18. 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.

  19. Leg strength and the VO2 max of older men.

    PubMed

    Lovell, D; Cuneo, R; Delphinus, E; Gass, G

    2011-04-01

    The purpose of the study was to determine if leg strength limits VO2 max and the ability to reach a plateau during VO2 max test in older men during cycle ergometry. Men aged 70-80 years were randomly selected into a strength training (ST, n=12) 3 times weekly for 16 weeks, followed by 4 weeks detraining or a non-training control group (C, n=12). Leg strength and VO2 max were assessed every 4 weeks for 20 weeks; body composition and cardiac function were assessed before and after 16 weeks training and after 4 weeks detraining. Leg strength, upper leg muscle mass (ULMM), arterial-venous O2 difference (a-v O2 difference) and VO2 max increased in the ST group (95±0.6%, 7±0.7%. 6.2±0.5% and 8±0.8%, respectively; P<0.05) after 16 weeks training. After 4 weeks detraining, gains in ULMM (50%) and strength (75%) were retained, but VO2 max and a-v O2 difference returned to pre-training levels. There was no change in the ability of the participants to reach a plateau during VO2 max testing over the 20-week study. These findings indicate that leg strength may not limit either VO2 max or the ability to plateau during VO2 max tests in older men during cycle ergometry.

  20. Effective-range approach and scaling laws for electromagnetic strength in neutron-halo nuclei.

    PubMed

    Typel, S; Baur, G

    2004-10-01

    We study low-lying multipole strength in neutron-halo nuclei. The strength depends only on a few low-energy constants: the neutron separation energy, the asymptotic normalization coefficient of the bound-state wave function, and the scattering length that contains the information on the interaction in the continuum. The shape of the transition probability shows a characteristic dependence on few scaling parameters and the angular momenta. The total E1 strength is related to the root-mean-square radius of the neutron wave function in the ground state and shows corresponding scaling properties. We apply our approach to the E1 strength distribution of 11Be.

  1. Preservation of eccentric strength in older adults: Evidence, mechanisms and implications for training and rehabilitation.

    PubMed

    Roig, Marc; Macintyre, Donna L; Eng, Janice J; Narici, Marco V; Maganaris, Constantinos N; Reid, W Darlene

    2010-06-01

    Overall reductions in muscle strength typically accompany the aging process. However, older adults show a relatively preserved capacity of producing eccentric strength. The preservation of eccentric strength in older adults is a well-established phenomenon, occurring indiscriminately across different muscle groups, independent of age-related architectural changes in muscle structure and velocity of movement. The mechanisms for the preservation of eccentric strength appear to be mechanical and cellular in origin and include both passive and active elements regulating muscle stiffness. The age-related accumulation of non-contractile material in the muscle-tendon unit increases passive stiffness, which might offer mechanical advantage during eccentric contractions. In addition, the preserved muscle tension and increased instantaneous stiffness of old muscle fibers during stretch increase active stiffness, which might enhance eccentric strength. The fact that the preservation of eccentric strength is present in people with chronic conditions when compared to age-matched healthy controls indicates that the aging process per se does not exclusively mediate the preservation of eccentric strength. Physical inactivity, which is common in elderly and people with chronic conditions, is a potential factor regulating the preservation of eccentric strength. When compared to concentric strength, the magnitude of preservation of eccentric strength in older adults ranges from 2% to 48% with a mean value of 21.6% from all studies. This functional reserve of eccentric strength might be clinically relevant, especially to initiate resistance training and rehabilitation programs in individuals with low levels of strength.

  2. Preservation of eccentric strength in older adults: Evidence, mechanisms and implications for training and rehabilitation

    PubMed Central

    Roig, Marc; MacIntyre, Donna L.; Eng, Janice J.; Narici, Marco V.; Maganaris, Constantinos N.; Reid, W. Darlene

    2012-01-01

    Overall reductions in muscle strength typically accompany the aging process. However, older adults show a relatively preserved capacity of producing eccentric strength. The preservation of eccentric strength in older adults is a well-established phenomenon, occurring indiscriminately across different muscle groups, independent of age-related architectural changes in muscle structure and velocity of movement. The mechanisms for the preservation of eccentric strength appear to be mechanical and cellular in origin and include both passive and active elements regulating muscle stiffness. The age-related accumulation of non-contractile material in the muscle-tendon unit increases passive stiffness, which might offer mechanical advantage during eccentric contractions. In addition, the preserved muscle tension and increased instantaneous stiffness of old muscle fibers during stretch increase active stiffness, which might enhance eccentric strength. The fact that the preservation of eccentric strength is present in people with chronic conditions when compared to age-matched healthy controls indicates that the aging process per se does not exclusively mediate the preservation of eccentric strength. Physical inactivity, which is common in elderly and people with chronic conditions, is a potential factor regulating the preservation of eccentric strength. When compared to concentric strength, the magnitude of the preservation of eccentric strength in older adults ranges from 2% to 48% with a mean value from all studies of 21.6%. This functional reserve of eccentric strength might be clinically relevant, especially to initiate resistance training and rehabilitation programs in individuals with low levels of strength. PMID:20303404

  3. 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.

  4. Strength Analysis of Glass-Fiber-Reinforced Plastic during Buckling,

    DTIC Science & Technology

    An algorithm is developed for calculating and analyzing the stress tensor by the experimental function of deflections during the buckling of glass ... fiber -reinforced plastic shells loaded with a hydrostatic load. Malmeyster’s theory of strength is used to qualitatively establish the possible points of shell failure. (Author-PL)

  5. 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…

  6. 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.

  7. 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

  8. The hyperbolic strength-duration relationship of defibrillation threshold.

    PubMed

    Irnich, Werner

    2008-08-01

    Defibrillation with square-wave pulses has proved to possess hyperbolic strength-duration relationship. Does such a hyperbolic relation also exist for exponentially decaying pulses as they are commonly used today? This paper hypothesizes that exponentially decaying pulses obey hyperbolic strength-duration relationship, calculates the consequences, and advises of how such thresholds should be investigated. If the strength-duration relationship exists for current, the corresponding charge threshold must be a Weiss' straight threshold line. In analogy, for exponentially decaying pulses, the integral of the amplitude over pulse duration (PD) must be calculated as a function of PD. If this function is linearly correlated, the mean voltage possesses a hyperbolic strength-duration relationship, whereas the peak voltage does not. Peak amplitude curves possess minima shifting to the right with increasing time constant RC limiting the allowed range of useful PDs. To prove that exponentially decaying pulses have a hyperbolic relationship, testing must be done in six steps that are demonstrated with results published in literature. Mean voltages have, indeed, hyperbolic strength-duration relationship. Chronaxie is not calculated correctly as long as peak voltage thresholds are correlated and PDs are greater than allowed.

  9. Development of strength in cements

    NASA Astrophysics Data System (ADS)

    Matkovic, B.

    1981-04-01

    The production of doped belite (dicalcium silicate) clinkers as a prospective means for saving energy in Portland cement production is described. This is accomplished by small additions of either barium sulfate (BaSO4), calcium tribasic phosphate (Ca5(PO4)3OH), or vanadium oxide (V2O5) to belite (Ca2SiO4) clinker. In addition to conserving energy, doping the belite with barium sulfate imparts greater strength to the resulting modified belite. Reactants, additives, and factors contributing to the fabrication of Sorel cement are described.

  10. 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.

  11. A multiscale strength model in HYDRA

    NASA Astrophysics Data System (ADS)

    Marinak, M. M.; Barton, N. R.

    2016-10-01

    We describe a multiscale strength model recently implemented in HYDRA. The model incorporates results from a hierarchy of methods which span from the atomistic to the continuum level. Those are obtained from focused physics codes that treat density functional theory, molecular statics, molecular dynamics, dislocation dynamics and continuum mechanics. The model is designed to handle extreme pressures and temperatures, and is especially appropriate for strain rates in excess of 104 s-1. As such it can be used to provide insight into HEDP experimental observations. The model has demonstrated success in capturing planar Rayleigh-Taylor growth for 1 Mbar shocks in Ta and V. This work was performed under the auspices of the Lawrence Livermore National Security, LLC, (LLNS) under Contract No. DE-AC52-07NA27344.

  12. 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.

  13. Pilates: Build Strength in Your Core Muscles

    MedlinePlus

    ... intimidating, but it's an accessible way to build strength in your core muscles for better posture, balance ... fanatics. It's actually an accessible way to build strength in your core muscles for better posture, balance ...

  14. CADDIS Volume 2. Sources, Stressors and Responses: Ionic Strength

    EPA Pesticide Factsheets

    Introduction to the ionic strength module, when to list ionic strength as a candidate cause, ways to measure ionic strength, simple and detailed conceptual diagrams for ionic strength, ionic strength module references and literature reviews.

  15. 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.

  16. 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.

  17. 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.

  18. 14 CFR 31.27 - Strength.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Strength. 31.27 Section 31.27 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: MANNED FREE BALLOONS Strength Requirements § 31.27 Strength. (a) The structure must be able...

  19. 14 CFR 31.27 - Strength.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Strength. 31.27 Section 31.27 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: MANNED FREE BALLOONS Strength Requirements § 31.27 Strength. (a) The structure must be able...

  20. 14 CFR 31.27 - Strength.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Strength. 31.27 Section 31.27 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: MANNED FREE BALLOONS Strength Requirements § 31.27 Strength. (a) The structure must be able...

  1. 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…

  2. 14 CFR 31.27 - Strength.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Strength. 31.27 Section 31.27 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: MANNED FREE BALLOONS Strength Requirements § 31.27 Strength. (a) The structure must be able...

  3. 7 CFR 29.3061 - Strength (tensile).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Strength (tensile). 29.3061 Section 29.3061... Type 93) § 29.3061 Strength (tensile). The stress a tobacco leaf can bear without tearing. Tensile strength is not an important element of quality in Burley tobacco....

  4. Improving the toughness of ultrahigh strength steel

    SciTech Connect

    Soto, Koji

    2002-01-01

    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.

  5. MinMaxDM distributions for an analysis of the tensile strength of a unidirectional composite

    NASA Astrophysics Data System (ADS)

    Paramonov, Yu.; Andersons, J.; Kleinhofs, M.; Blumbergs, I.

    2010-09-01

    An analysis of the tensile strength of some fiber or fiber bundle specimens is presented. The specimens are modeled as chains of links consisting of longitudinal elements (LEs) with different cumulative distribution functions of strength, corresponding to the presence and absence of defects. Each link is considered as a system of parallel LEs a part of which can have defects. In the simplest case, the strength of defective elements is assumed equal to zero. The strength of a link is determined by the maximum average stress the link can sustain under a growing load. To calculate the stress, the randomized Daniels model or the theory of Markov chains is used. The strength of specimens is determined by the minimum strength of links. The concept of MinMaxDM family of distribution functions is introduced. A numerical example of processing experimental results for a monolayer of carbon bundles is presented.

  6. Friction Stir Spot Welding of Advanced High Strength Steels

    SciTech Connect

    Hovanski, Yuri; Santella, M. L.; Grant, Glenn J.

    2009-12-28

    Friction stir spot welding was used to join two advanced high-strength steels using polycrystalline cubic boron nitride tooling. Numerous tool designs were employed to study the influence of tool geometry on weld joints produced in both DP780 and a hot-stamp boron steel. Tool designs included conventional, concave shouldered pin tools with several pin configurations; a number of shoulderless designs; and a convex, scrolled shoulder tool. Weld quality was assessed based on lap shear strength, microstructure, microhardness, and bonded area. Mechanical properties were functionally related to bonded area and joint microstructure, demonstrating the necessity to characterize processing windows based on tool geometry.

  7. 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…

  8. 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…

  9. 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

  10. Nondestructive Determination of Bond Strength

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Although many nondestructive techniques have been applied to detect disbonds in adhesive joints, no absolutely reliable nondestructive method has been developed to detect poor adhesion and evaluate the strength of bonded joints prior to the present work which used nonlinear ultrasonic methods to investigate adhesive bond cure conditions. Previously, a variety of linear and nonlinear ultrasonic methods with water coupling had been used to study aluminum-adhesive-aluminum laminates, prepared under different adhesive curing conditions, for possible bond strength determination. Therefore, in the course of this research effort, a variety of finite-amplitude experimental methods which could possibly differentiate various cure conditions were investigated, including normal and oblique incidence approaches based on nonlinear harmonic generation as well as several non-collinear two-wave interaction approaches. Test samples were mechanically scanned in various ways with respect to the focus of a transmitting transducer operated at several variable excitation frequencies and excitation levels. Even when powerful sample-related resonances were exploited by means of a frequency scanning approach, it was very difficult to isolate the nonlinear characteristics of adhesive bonds. However, a multi-frequency multi-power approach was quite successful and reliable. Ultrasonic tone burst signals at increasing power levels, over a wide frequency range, were transmitted through each bond specimen to determine its excitation dependent nonlinear harmonic resonance behavior. Relative amplitude changes were observed particularly in the higher harmonic spectral data and analyzed using a local displacement and strain analysis in the linear approximation. Two analysis approaches of the excitation-dependent data at specific resonances were found to be quite promising. One of these approaches may represent a very robust algorithm for classifying an adhesive bond as being properly cured or not

  11. The role of strengths in anger and conduct problems in maltreated adolescents.

    PubMed

    Go, Monica; Chu, Chi Meng; Barlas, Joanna; Chng, Grace S

    2017-02-24

    Despite multi-type maltreatment, some individuals demonstrate positive adaptation and continue to develop in a healthy way. A multitude of strength factors have been linked to adaptive functioning and resilience, but this has not been adequately examined in maltreated adolescent's psychosocial functioning. This study sought to examine the role of strengths such as having talents/interests, family relationships, educational support, the role of the recognition and application of these strengths, and the role of multi-type maltreatment on anger control and conduct problems. One hundred and thirty participants (61 males; 69 females) aged 13-19 years old were rated using the Singapore version of Child and Adolescent Needs and Strengths (CANS) tool. The results revealed that certain strengths were associated with anger and conduct problems, but the recognition and application of strengths emerged as a consistently significant predictor for both outcomes. Hence, to understand and apply one's strengths may be equally as important as merely possessing those strengths. This study extends current understanding of the importance of strengths with a group of maltreated adolescents in an Asian context. Adopting a person-centered and strength-based approach will further enhance the effectiveness of interventions and improve outcomes for maltreated adolescents living in residential care.

  12. Strength of Welded Aircraft Joints

    NASA Technical Reports Server (NTRS)

    Brueggeman, W C

    1937-01-01

    This investigation is a continuation of work started in 1928 and described in NACA-TR-348 which shows that the insertion of gusset plates was the most satisfactory way of strengthening a joint. Additional tests of the present series show that joints of this type could be improved by cutting out the portion of the plate between the intersecting tubes. T and lattice joints in thin-walled tubing 1 1/2 by 0.020 inch have somewhat lower strengths than joints in tubing of greater wall thickness because of failure by local buckling. In welding the thin-walled tubing, the recently developed "carburizing flux" process was found to be the only method capable of producing joints free from cracks. The "magnetic powder" inspection was used to detect cracks in the joints and flaws in the tubing.

  13. 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.

  14. 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.

  15. 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.

  16. Community-wide distribution of predator-prey interaction strength in kelp forests.

    PubMed

    Sala, Enric; Graham, Michael H

    2002-03-19

    The strength of interactions between predators and their prey (interaction strength) varies enormously among species within ecological communities. Understanding the community-wide distribution of interaction strengths is vital, given that communities dominated by weak interactions may be more stable and resistant to invasion. In the oceans, previous studies have reported log-normal distributions of per capita interaction strength. We estimated the distribution of predator-prey interaction strengths within a subtidal speciose herbivore community (45 species). Laboratory experiments were used to determine maximum per capita interaction strengths for eight species of herbivores (including amphipods, isopods, gastropods, and sea urchins) that graze on giant kelp (Macrocystis pyrifera) microscopic stages. We found that maximum per capita interaction strength saturated as a function of individual herbivore biomass, likely caused by predator/prey size thresholds. Incorporating this nonlinearity, we predicted maximum per capita interaction strength for the remaining herbivore species. The resulting distribution of per capita interaction strengths was bimodal, in striking contrast to previous reports from other communities. Although small herbivores often had per capita interaction strengths similar to larger herbivores, their tendency to have greater densities in the field increased their potential impact as grazers. These results indicate that previous conclusions about the distributions of interaction strength in natural communities are not general, and that intermediate-sized predators can under realistic circumstances represent the most effective consumers in natural communities.

  17. Adhesive strength of autologous fibrin glue.

    PubMed

    Yoshida, H; Hirozane, K; Kamiya, A

    2000-03-01

    To establish an easy and rapid method for measuring the adhesive strength of fibrin glue and to clarify the factor(s) most affecting the strength, a study was made on the effect of the concentration of plasma components on the strength of cryoprecipitate (Cryo) prepared from a subject's own autologous plasma to be used as fibrin glue. The adhesive strength of the Cryo was measured with various supporting materials instead of animal skin using a tester of tension and compression. The results were as follows: (1) the strength of Cryo applied to ground flat glass (4 cm2) was significantly greater than that applied to clear glass, clear plastic, or smooth and flat wood chips; (2) the adhesive strength of Cryo depended on the concentration of thrombin with the optimal concentration being 50 units/ml; (3) the concentration of CaCl2 did not affect the adhesive strength of Cryo; (4) the adhesive reaction was dependent on the temperature and the adhesive strength more quickly reached a steady state at 37 degrees C than at lower temperature; (5) the adhesive strength was correlated well with the total concentration of fibrinogen and fibronectin. These results indicate that the adhesive strength of Cryo can be easily and quickly evaluated using a tester and ground glass with thrombin at 50 units/ml, and that the adhesive strength of Cryo can be predicted from the total concentration of fibrinogen and fibronectin.

  18. 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.

  19. Strength of biodegradable polypropylene tapes filled with a modified starch

    NASA Astrophysics Data System (ADS)

    Vinidiktova, N. S.; Ermolovich, O. A.; Goldade, V. A.; Pinchuk, L. S.

    2006-05-01

    The possibility of creating composite materials with high deformation and strength characteristics based on polypropylene (PP) and a natural polysaccharide in the form of a modified starch (MS) has been studied. The modified starch is shown to interact chemically with functional groups of PP, thereby positively affecting the physicomechanical properties, structure, and water absorption properties of films and oriented flat fibers based on starch-filled PP. The strength characteristics of both oriented and unoriented composites are 1.5-2.0 times as high as those of the initial PP. The water absorption ability of the materials varies symbatically with content of MS, which points to the dominant contribution of interactions at the PP-MS interface. The introduction of MS into synthetic polymers offers a possibility of producing new ecologically safe materials with high strength characteristics.

  20. Complexity of generic biochemical circuits: topology versus strength of interactions

    NASA Astrophysics Data System (ADS)

    Tikhonov, Mikhail; Bialek, William

    2016-12-01

    The historical focus on network topology as a determinant of biological function is still largely maintained today, illustrated by the rise of structure-only approaches to network analysis. However, biochemical circuits and genetic regulatory networks are defined both by their topology and by a multitude of continuously adjustable parameters, such as the strength of interactions between nodes, also recognized as important. Here we present a class of simple perceptron-based Boolean models within which comparing the relative importance of topology versus interaction strengths becomes a quantitatively well-posed problem. We quantify the intuition that for generic networks, optimization of interaction strengths is a crucial ingredient of achieving high complexity, defined here as the number of fixed points the network can accommodate. We propose a new methodology for characterizing the relative role of parameter optimization for topologies of a given class.