1,326 research outputs found

    New T=1 effective interactions for the f5/2 p3/2 p1/2 g9/2 model space; Implications for valence-mirror symmetry and seniority isomers

    Full text link
    New shell model Hamiltonians are derived for the T=1 part of the residual interaction in the f5/2 p3/2 p1/2 g9/2 model space based on the analysis and fit of the available experimental data for 57Ni-78Ni isotopes and 77Cu-100Sn isotones. The fit procedure, properties of the determined effective interaction as well as new results for valence-mirror symmetry and seniority isomers for nuclei near 78Ni and 100Sn are discussed.Comment: 4 pages, 5 figure

    Pairing-excitation versus intruder states in 68Ni and 90Zr

    Full text link
    A discussion on the nature of the 0+ states in 68Ni (Z=28, N=40) is presented and a comparison is made with its valence counterpart 90Zr (Z=40, N=50). Evidence is given for a 0+ proton intruder state at only ~2.2 MeV excitation energy in 68Ni, while the analogous neutron intruder states in 90Zr reside at 4126 keV and 5441 keV. The application of a shell-model description of 0+ intruder states reveals that many pair-scattered neutrons across N=40 have to be involved to explain the low excitation energy of the proton-intruder configuration in 68Ni.Comment: 10 pages, 2 figures, 1 tabl

    How magic is the magic 68Ni nucleus?

    Get PDF
    We calculate the B(E2) strength in 68Ni and other nickel isotopes using several theoretical approaches. We find that in 68Ni the gamma transition to the first 2+ state exhausts only a fraction of the total B(E2) strength, which is mainly collected in excited states around 5 MeV. This effect is sensitive to the energy splitting between the fp shell and the g_{9/2}orbital. We argue that the small experimental B(E2) value is not strong evidence for the double-magic character of 68Ni.Comment: 4 pages, 4 figure

    Logistics salience impact on logistics capabilities and performance

    Get PDF
    Purpose – The purpose of this manuscript is to assess the impact of logistics salience on logistics capabilities and performance. Specifically, the impact of logistics salience on logistics innovativeness and logistics service differentiation is measured along with logistics innovativeness and logistics service differentiation effect on logistics performance. Design/methodology/approach – Conclusions were drawn from survey data gathered from logistics and supply chain managers at US firms. Structural equation modelling was utilized to measure the statistical significance of the hypothesized model paths with all findings meeting the basic requirements of interpretation. Findings – The results suggest that logistics salience positively impacts both logistics innovativeness and logistics service differentiation. Logistics innovativeness and logistics service differentiation both positively influence logistics performance. These findings give credence to the resource based view of the firm which states that resources lead to capabilities which leads to performance. Research limitations/implications – Conclusions based on the study’s results highlight the importance of logistics within firms and indicate that the function must be made salient throughout the firm to further capitalize on the benefits of logistics. These benefits include enhanced logistics capabilities and their eventual impact on logistics performance. Originality/value – Using the resource based view of the firm as the theoretical framework, the manuscript supports the notion that logistics salience is an important resource for firms looking to provide differentiated services and innovative logistics operations to their customers

    Enhancing Dyadic Performance Through Boundary Spanners and Innovation: An Assessment of Service Provider–Customer Relationships

    Get PDF
    Firms recognize that working together through collaborative relationships offers potential benefits such as improving cooperation, information sharing, and overall performance. An additional and extremely valuable benefit of working together is the potential for creating innovative business approaches and solutions. Thus, developing external linkages has become a higher priority within many organizations. Boundary spanning employees offer one means of achieving closer cross‐firm relationships. We investigate the roles of boundary spanners by examining service providers and their relationships with customers. More specifically, we examine boundary spanning employees that are physically on‐site at customer facilities. Results provide strong support that boundary spanners perceiving higher levels of external organizational support from a client subsequently develop affective commitment to the customer. This, in turn, drives knowledge exchange and logistics innovation. A relationship between logistics innovation and performance (of service providers and of customers) was also found. Managerial implications of the research findings are discussed and suggestions presented covering future research

    Dominant g(9/2)^2 neutron configuration in the 4+1 state of 68Zn based on new g factor measurements

    Full text link
    The gg factor of the 41+4_1^+ state in 68^{68}Zn has been remeasured with improved energy resolution of the detectors used. The value obtained is consistent with the previous result of a negative gg factor thus confirming the dominant 0g9/20g_{9/2} neutron nature of the 41+4_1^+ state. In addition, the accuracy of the gg factors of the 21+2_1^+, 22+2_2^+ and 31−3_1^- states has been improved an d their lifetimes were well reproduced. New large-scale shell model calculations based on a 56^{56}Ni core and an 0f5/21pg9/20f_{5/2}1pg_{9/2} model space yield a theoretical value, g(41+)=+0.008g(4_1^+) = +0.008. Although the calculated value is small, it cannot fully explain the experimental value, g(41+)=−0.37(17)g(4_1^+) = -0.37(17). The magnitude of the deduced B(E2) of the 41+4_1^+ and 21+2_1^+ transition is, however, rather well described. These results demonstrate again the importance of gg factor measurements for nuclear structure determination s due to their specific sensitivity to detailed proton and neutron components in the nuclear wave functions.Comment: 7 pages, 3 figs, submitted to PL

    Core excitations across the neutron shell gap in ÂČ⁰⁷Tl

    Get PDF
    The single closed-neutron-shell, one proton-hole nucleus 207Tl was populated in deep-inelastic collisions of a 208Pb beam with a 208Pb target. The yrast and near-yrast level scheme has been established up to high excitation energy, comprising an octupol

    Tensor part of the Skyrme energy density functional. II: Deformation properties of magic and semi-magic nuclei

    Full text link
    We study systematically the impact of the time-even tensor terms of the Skyrme energy density functional, i.e. terms bilinear in the spin-current tensor density, on deformation properties of closed shell nuclei corresponding to 20, 28, 40, 50, 82, and 126 neutron or proton shell closures. We compare results obtained with three different families of Skyrme parameterizations whose tensor terms have been adjusted on properties of spherical nuclei: (i) TIJ interactions proposed in the first paper of this series [T. Lesinski et al., Phys. Rev. C 76, 014312 (2007)] which were constructed through a complete readjustment of the rest of the functional (ii) parameterizations whose tensor terms have been added perturbatively to existing Skyrme interactions, with or without readjusting the spin-orbit coupling constant. We analyse in detail the mechanisms at play behind the impact of tensor terms on deformation properties and how studying the latter can help screen out unrealistic parameterizations. It is expected that findings of the present paper are to a large extent independent of remaining deficiencies of the central and spin-orbit interactions, and will be of great value for the construction of future, improved energy functionals.Comment: 32 pages revte

    Outcomes Following Anterior Cruciate Ligament Reconstruction with Patellar Tendon vs Hamstring Autografts: A Systematic Review of Randomized Controlled Trials with a Mean Follow-up of 15 Years

    Get PDF
    BACKGROUND: The two most common surgical treatment modalities for anterior cruciate ligament reconstruction (ACL), patellar tendon (PT) and hamstring tendon (HS) autografts, have been shown to have outcomes that are both similar and favorable; however, many of these are short or intermediate-term. The objective of this systematic review is to evaluate randomized controlled trials (RCTs) with a minimum 10-year follow-up data to compare the long-term outcomes of ACL reconstructions performed using PT and HS autografts. METHODS: This systematic review followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A search of three databases (PubMed, Cochrane and EMBASE) was performed to identify RCTs with a minimum of 10-year follow-up that compared clinical and/or functional outcomes between PT and HS autografts. RESULTS: Four RCTs with a total of 299 patients were included in the study. The mean follow-up ranged from 10.2 to 17 years (mean, 14.79 years). No significant differences in knee laxity or clinical outcome scores were demonstrated in any of the studies. One study found that PT autografts were significantly more likely to have osteoarthritis identified by radiographic findings. Two studies found that patients with PT autografts reported increase kneeling pain, while none of the four studies reported a difference in anterior knee pain. There were no significant differences in graft failure rates. CONCLUSION: This review demonstrates no long-term difference in clinical or functional outcomes between PT and HS autografts. However, radiographic and subjective outcomes indicate that patients with PT autografts may experience greater kneeling pain and osteoarthritis. Therefore, orthopedic surgeons should consider patient-centric factors when discussing graft options with patients
    • 

    corecore