1,010 research outputs found

    Constraints on regional drivers of relative sea-level change around Cordova, Alaska

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    New records of paleoenvironmental change from two lakes near Cordova, south central Alaska, combined with analysis of previously reported sediment sequences from the adjacent Copper River Delta, provide quantitative constraints on a range of Earth system processes through their expression in relative sea-level change. Basal sediment ages from Upper Whitshed Lake indicate ice-free conditions by at least 14,140 – 15,040 cal yr BP. While Upper and Lower Whitshed Lakes provide only upper limits to relative sea-level change, interbedded layers of freshwater peat and intertidal silt extending more than 11 m below present sea level in Copper River Delta indicate net submergence over the last 6000 years and multiple earthquake deformation cycles. In contrast, Lower Whitshed Lake, situated just above present high tide level, records only one episode of marine sedimentation, commencing AD 1120 – 1500, that we interpret as the result of isostatic subsidence due to Little Ice Age mass accumulation of the Chugach Mountain glaciers. Lower Whitshed Lake also records isostatic uplift at the end of the Little Ice Age before the end of marine sedimentation caused by ~1.5 m coseismic uplift in the great Alaska earthquake of AD 1964. We successfully explain the records of relative sea-level change from both Copper River Delta and the Whitshed Lakes by integrating the effects of eustatic sea-level rise, glacial isostasy, earthquake deformation cycles, sediment loading, sediment compaction and late Holocene changes in glacier mass into a single model. This approach provides initial quantitative constraints on the individual contributions of these processes. Taking reasonable estimates of eustasy, post-Last Glacial Maximum and Neoglacial glacial isostatic adjustment and a simple earthquake deformation cycle, we demonstrate that sediment loading and sediment compaction are both contributors to relative sea-level rise at Copper River Delta, together producing subsidence averaging approximately 1.2 mm yr-1 over the mid to late Holocene. Further isolation basin studies have the potential to greatly improve our understanding of the individual contributions of these processes in this highly dynamic region

    Electro-elastic tuning of single particles in individual self-assembled quantum dots

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    We investigate the effect of uniaxial stress on InGaAs quantum dots in a charge tunable device. Using Coulomb blockade and photoluminescence, we observe that significant tuning of single particle energies (~ -0.5 meV/MPa) leads to variable tuning of exciton energies (+18 to -0.9 micro-eV/MPa) under tensile stress. Modest tuning of the permanent dipole, Coulomb interaction and fine-structure splitting energies is also measured. We exploit the variable exciton response to tune multiple quantum dots on the same chip into resonance.Comment: 16 pages, 4 figures, 1 table. Final versio

    Public attitudes to inequality in water distribution: Insights from preferences for water reallocation from irrigators to Aboriginal Australians

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    Water allocation regimes that adjudicate between competing uses are in many countries under pressure to adapt to increasing demands, climate‐driven shortages, expectations for equity of access, as well as societal changes in values and priorities. International authorities expound standards for national allocation regimes that include robust processes for addressing the needs of ‘new entrants' and for varying existing entitlements within sustainable limits. The claims of Indigenous peoples to water represents a newly recognised set of rights and interests that will test the ability of allocation regimes to address the global water governance goal of equity. No study has sought to identify public attitudes or willingness to pay for a fairer allocation of water rights between Indigenous and non‐Indigenous people. We surveyed households from the jurisdictions of Australia's Murray‐Darling Basin, a region undergoing a historic government‐led recovery of water, and found that 69.2% of respondents support the principle of reallocating a small amount of water from irrigators to Aboriginal people via the water market. Using contingent valuation, we estimated households are willing to pay A21.78inaone‐offlevy.Theaggregatevaluecalculatedforhouseholdsinthebasinâ€ČsjurisdictionswasA21.78 in a one‐off levy. The aggregate value calculated for households in the basin's jurisdictions was A74.5 million, which is almost double a recent government commitment to fund the acquisition of entitlements for Aboriginal nations of this basin. Results varied by state of residency and affinity with environmental groups. An information treatment that presented narrative accounts from Aboriginal people influenced the results. Insights from this study can inform water reallocation processes

    Unlimited Energy Gain in the Laser-Driven Radiation Pressure Dominant Acceleration of Ions

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    The energy of the ions accelerated by an intense electromagnetic wave in the radiation pressure dominated regime can be greatly enhanced due to a transverse expansion of a thin target. The expansion decreases the number of accelerated ions in the irradiated region increasing the energy and the longitudinal velocity of remaining ions. In the relativistic limit, the ions become phase-locked with respect to the electromagnetic wave resulting in the unlimited ion energy gain. This effect and the use of optimal laser pulse shape provide a new approach for great enhancing the energy of laser accelerated ions.Comment: 30 pages, 9 figures, misprints correcte

    Universal Rights and Wrongs

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    This paper argues for the important role of customers as a source of competitive advantage and firm growth, an issue which has been largely neglected in the resource-based view of the firm. It conceptualizes Penrose’s (1959) notion of an ‘inside track’ and illustrates how in-depth knowledge about established customers combines with joint problem-solving activities and the rapid assimilation of new and previously unexploited skills and resources. It is suggested that the inside track represents a distinct and perhaps underestimated way of generating rents and securing long-term growth. This also implies that the sources of sustainable competitive advantage in important respects can be sought in idiosyncratic interfirm relationships rather than within the firm itself

    Measurement of CP violating asymmetries in B^0 -> K^+K^- K^0_S decays with a time-dependent Dalitz approach

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    We report a measurement of CPCP violating asymmetries in B0(B‟0)→K+K−KS0B^0(\overline{B}^0) \to K^+ K^- K^0_S decays with a time-dependent Dalitz approach. This analysis is based on a data sample of 657×106657\times 10^6 BB‟B\overline{B} pairs accumulated at the ΄(4S)\Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e−e^+e^- collider. As the result of an unbinned maximum likelihood fit to the selected candidates, the mixing-induced and direct CPCP violation parameters, ϕ1eff\phi^{\rm eff}_1 and ACP{\cal A}_{CP} are obtained for B0→ϕ(1020)KS0B^0 \to \phi(1020) K^0_S, B0→f0(980)KS0B^0 \to f_0(980) K^0_S and other B0→K+K−KS0B^0 \to K^+ K^- K^0_S decays. We find four solutions that describe the data. There are \{eqnarray*} \phi_1^{\rm eff}(B^0\to \phi(1020) K^0_S) & = & (32.2 \pm 9.0 \pm 2.6 \pm 1.4)^{\circ}; \phi_1^{\rm eff}(B^0\to \phi(1020) K^0_S) & = & (26.2 \pm 8.8 \pm 2.7 \pm 1.2)^{\circ};\\ \phi_1^{\rm eff}(B^0\to \phi(1020) K^0_S) & = & (27.3 \pm 8.6 \pm 2.8 \pm 1.3)^{\circ}\; {\rm and}\\ \phi_1^{\rm eff}(B^0\to \phi(1020) K^0_S) & = & (24.3 \pm 8.0 \pm 2.9 \pm 5.2)^{\circ}.{eqnarray*}\ The values for the CPCP violating phase in B0→ϕ(1020)KS0B^0\to \phi(1020) K^0_S are similar but other properties of the Dalitz plot are quite different for the four solutions. These four solutions have consistent ϕ1eff\phi^{\rm eff}_1 values for all three BB meson decay channels and none of them deviates significantly from the values measured in B→(ccˉ)K0B \to (c\bar{c}) K^0 decays with the currently available statistics. In addition, we find no significant direct CPCP violation.Comment: submitted to PR

    Measurement of CP violating asymmetries in B^0 -> K^+K^- K^0_S decays with a time-dependent Dalitz approach

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    We report a measurement of CPCP violating asymmetries in B0(B‟0)→K+K−KS0B^0(\overline{B}^0) \to K^+ K^- K^0_S decays with a time-dependent Dalitz approach. This analysis is based on a data sample of 657×106657\times 10^6 BB‟B\overline{B} pairs accumulated at the ΄(4S)\Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e−e^+e^- collider. As the result of an unbinned maximum likelihood fit to the selected candidates, the mixing-induced and direct CPCP violation parameters, ϕ1eff\phi^{\rm eff}_1 and ACP{\cal A}_{CP} are obtained for B0→ϕ(1020)KS0B^0 \to \phi(1020) K^0_S, B0→f0(980)KS0B^0 \to f_0(980) K^0_S and other B0→K+K−KS0B^0 \to K^+ K^- K^0_S decays. We find four solutions that describe the data. There are \{eqnarray*} \phi_1^{\rm eff}(B^0\to \phi(1020) K^0_S) & = & (32.2 \pm 9.0 \pm 2.6 \pm 1.4)^{\circ}; \phi_1^{\rm eff}(B^0\to \phi(1020) K^0_S) & = & (26.2 \pm 8.8 \pm 2.7 \pm 1.2)^{\circ};\\ \phi_1^{\rm eff}(B^0\to \phi(1020) K^0_S) & = & (27.3 \pm 8.6 \pm 2.8 \pm 1.3)^{\circ}\; {\rm and}\\ \phi_1^{\rm eff}(B^0\to \phi(1020) K^0_S) & = & (24.3 \pm 8.0 \pm 2.9 \pm 5.2)^{\circ}.{eqnarray*}\ The values for the CPCP violating phase in B0→ϕ(1020)KS0B^0\to \phi(1020) K^0_S are similar but other properties of the Dalitz plot are quite different for the four solutions. These four solutions have consistent ϕ1eff\phi^{\rm eff}_1 values for all three BB meson decay channels and none of them deviates significantly from the values measured in B→(ccˉ)K0B \to (c\bar{c}) K^0 decays with the currently available statistics. In addition, we find no significant direct CPCP violation.Comment: submitted to PR
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