214 research outputs found

    The impact of space and space-related activities on a local economy. a case study of boulder, colorado. part ii- the income-product accounts

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    Total impact of space and space related activities on local economy of Boulder, Colorado - income-product account

    Decoherence induced by a dynamic spin environment (II): Disentanglement by local system-environment interactions

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    This article studies the decoherence induced on a system of two qubits by local interactions with a spin chain with nontrivial internal dynamics (governed by an XY Hamiltonian). Special attention is payed to the transition between two limits: one in which both qubits interact with the same site of the chain and another one where they interact with distant sites. The two cases exhibit different behaviours in the weak and strong coupling regimes: when the coupling is weak it is found that decoherence tends to decrease with distance, while for strong coupling the result is the opposite. Also, in the weak coupling case, the long distance limit is rapidly reached, while for strong coupling there is clear evidence of an expected effect: environment-induced interactions between the qubits of the system. A consequence of this is the appearance of quasiperiodic events that can be interpreted as ``sudden deaths'' and ``sudden revivals'' of the entanglement between the qubits, with a time scale related to the distance between them.Comment: 10 pages, 9 figure

    Evaluation of a resistance training program for adults with or at risk of developing diabetes: an effectiveness study in a community setting

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    Background: To examine the effects of a community-based resistance training program (Lift for Life) on waist circumference and functional measures in adults with or at risk of developing type 2 diabetes.Methods: Lift for Life is a research-to-practice initiative designed to disseminate an evidence-based resistance training program for adults with or at risk of developing type 2 diabetes to existing health and fitness facilities in the Australian community. A retrospective assessment was undertaken on 86 participants who had accessed the program within 4 active providers in Melbourne, Australia. The primary goal of this longitudinal study was to assess the effectiveness of a community-based resistance training program, thereby precluding a randomized, controlled study design. Waist circumference, lower body (chair sit-to-stand) and upper body (arm curl test) strength, and agility (timed up-and-go) measures were collected at baseline and repeated at 2 months (n = 86) and again at 6 months (n = 32).Results: Relative to baseline, there was a significant decrease in mean waist circumference (-1.9 cm, 95% CI: -2.8 to -1.0) and the timed agility test (-0.8 secs, 95% CI: -1.0 to -0.6); and significant increases in lower body (number of repetitions: 2.2, 95% CI: 1.4-3.0) and upper body (number of repetitions: 3.8, 95% CI: 3.0-4.6) strength at the completion of 8 weeks. Significant differences remained at the 16 week assessment. Pooled time series regression analyses adjusted for age and sex in the 32 participants who had complete measures at baseline and 24-week follow-up revealed significant time effects for waist circumference and functional measures, with the greatest change from baseline observed at the 24-week assessment.Conclusions: These findings indicate that an evidence-based resistance training program administered in the community setting for those with or at risk of developing type 2 diabetes, can lead to favorable health benefits, including reductions in central obesity and improved physical function

    The relationship of femoral neck shaft angle and adiposity to greater trochanteric pain syndrome in women. A case control morphology and anthropometric study

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    OBJECTIVE To evaluate if pelvic or hip width predisposed women to developing greater trochanteric pain syndrome (GTPS). DESIGN Prospective case control study. PARTICIPANTS Four groups were included in the study: those gluteal tendon reconstructions (n=31, GTR), those with conservatively managed GTPS (n=29), those with hip osteoarthritis (n=20, OA) and 22 asymptomatic participants (ASC). METHODS Anterior-posterior pelvic x-rays were evaluated for femoral neck shaft angle; acetabular index, and width at the lateral acetabulum, and the superior and lateral aspects of the greater trochanter. Body mass index, and waist, hip and greater trochanter girth were measured. Data were analysed using a one-way analysis of variance (ANOVA; posthoc Scheffe analysis), then multivariate analysis. RESULTS The GTR group had a lower femoral neck shaft angle than the other groups (p=0.007). The OR (95% CI) of having a neck shaft angle of less than 134°, relative to the ASC group: GTR=3.33 (1.26 to 8.85); GTPS=1.4 (0.52 to 3.75); OA=0.85 (0.28 to 2.61). The OR of GTR relative to GTPS was 2.4 (1.01 to 5.6). No group difference was found for acetabular or greater trochanter width. Greater trochanter girth produced the only anthropometric group difference (mean (95% CI) in cm) GTR=103.8 (100.3 to 107.3), GTPS=105.9 (100.2 to 111.6), OA=100.3 (97.7 to 103.9), ASC=99.1 (94.7 to 103.5), (ANOVA: p=0.036). Multivariate analysis confirmed adiposity is associated with GTPS. CONCLUSION A lower neck shaft angle is a risk factor for, and adiposity is associated with, GTPS in women

    Classicality in discrete Wigner functions

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    Gibbons et al. [Phys. Rev. A 70, 062101(2004)] have recently defined a class of discrete Wigner functions W to represent quantum states in a Hilbert space with finite dimension. We show that the only pure states having non-negative W for all such functions are stabilizer states, as conjectured by one of us [Phys. Rev. A 71, 042302 (2005)]. We also show that the unitaries preserving non-negativity of W for all definitions of W form a subgroup of the Clifford group. This means pure states with non-negative W and their associated unitary dynamics are classical in the sense of admitting an efficient classical simulation scheme using the stabilizer formalism.Comment: 10 pages, 1 figur

    Efficient photoionization for barium ion trapping using a dipole-allowed resonant two-photon transition

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    Two efficient and isotope-selective resonant two-photon ionization techniques for loading barium ions into radio-frequency (RF)-traps are demonstrated. The scheme of using a strong dipole-allowed transition at \lambda=553 nm as a first step towards ionization is compared to the established technique of using a weak intercombination line (\lambda=413 nm). An increase of two orders of magnitude in the ionization efficiency is found favoring the transition at 553 nm. This technique can be implemented using commercial all-solid-state laser systems and is expected to be advantageous compared to other narrowband photoionization schemes of barium in cases where highest efficiency and isotope-selectivity are required.Comment: 8 pages, 5 figure

    One-neutron removal reactions on light neutron-rich nuclei

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    A study of high energy (43--68 MeV/nucleon) one-neutron removal reactions on a range of neutron-rich psd-shell nuclei (Z = 5--9, A = 12--25) has been undertaken. The inclusive longitudinal and transverse momentum distributions for the core fragments, together with the cross sections have been measured for breakup on a carbon target. Momentum distributions for reactions on tantalum were also measured for a subset of nuclei. An extended version of the Glauber model incorporating second order noneikonal corrections to the JLM parametrisation of the optical potential has been used to describe the nuclear breakup, whilst the Coulomb dissociation is treated within first order perturbation theory. The projectile structure has been taken into account via shell model calculations employing the psd-interaction of Warburton and Brown. Both the longitudinal and transverse momentum distributions, together with the integrated cross sections were well reproduced by these calculations and spin-parity assignments are thus proposed for 15^{15}B, 17^{17}C, 1921^{19-21}N, 21,23^{21,23}O, 2325^{23-25}F. In addition to the large spectroscopic amplitudes for the ν2\nu2s1/2_{1/2} intruder configuration in the N=9 isotones,14^{14}B and 15^{15}C, significant ν2\nu2s1/22_{1/2}^2 admixtures appear to occur in the ground state of the neighbouring N=10 nuclei 15^{15}B and 16^{16}C. Similarly, crossing the N=14 subshell, the occupation of the ν2\nu2s1/2_{1/2} orbital is observed for 23^{23}O, 24,25^{24,25}F. Analysis of the longitudinal and transverse momentum distributions reveals that both carry spectroscopic information, often of a complementary nature. The general utility of high energy nucleon removal reactions as a spectroscopic tool is also examined.Comment: 50 pages, 19 figures, submitted to Phys. Rev.

    Pontine capillary telangiectasia as visualized on MR imaging causing a clinical picture resembling basilar-type migraine: a case report

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    A case of presumed pontine capillary telangiectasia in an 18-year-old woman with a clinical diagnosis of basilar-type migraine is reported. Since both are very rare diagnoses, this case provides some evidence to suggest that pontine capillary telangiectasia might cause a clinical picture resembling basilar-type migraine

    prevalence of inadequate intakes and associated health outcomes

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    © 2022 The Authors. Annals of the New York Academy of Sciences published by Wiley Periodicals LLC on behalf of New York Academy of Sciences.Dietary calcium deficiency is considered to be widespread globally, with published estimates suggesting that approximately half of the world's population has inadequate access to dietary calcium. Calcium is essential for bone health, but inadequate intakes have also been linked to other health outcomes, including pregnancy complications, cancers, and cardiovascular disease. Populations in low- and middle-income countries (LMICs) are at greatest risk of low calcium intakes, although many individuals in high-income countries (HICs) also do not meet recommendations. Paradoxically, many LMICs with lower calcium intakes show lower rates of osteoporotic fracture as compared with HICs, though data are sparse. Calcium intake recommendations vary across agencies and may need to be customized based on other dietary factors, health-related behaviors, or the risk of calcium-related health outcomes. The lack of standard methods to assess the calcium status of an individual or population has challenged efforts to estimate the prevalence of calcium deficiency and the global burden of related adverse health consequences. This paper aims to consolidate available evidence related to the global prevalence of inadequate calcium intakes and associated health outcomes, with the goal of providing a foundation for developing policies and population-level interventions to safely improve calcium intake and status where necessary.publishersversionepub_ahead_of_prin

    Trapping ions with lasers

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    This work theoretically addresses the trapping an ionized atom with a single valence electron by means of lasers, analyzing qualitatively and quantitatively the consequences of the net charge of the particle. In our model, the coupling between the ion and the electromagnetic field includes the charge monopole and the internal dipole, within a multipolar expansion of the interaction Hamiltonian. Specifically, we perform a Power-Zienau-Woolley transformation, taking into account the motion of the center of mass. The net charge produces a correction in the atomic dipole which is of order me/Mm_e/M with mem_e the electron mass and MM the total mass of the ion. With respect to neutral atoms, there is also an extra coupling to the laser field which can be approximated by that of the monopole located at the position of the center of mass. These additional effects, however, are shown to be very small compared to the dominant dipolar trapping term.Comment: 11 pages, 2 figures, replaced with published version (minor changes
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