On the functional relationship between biodiversity and economic value

Biodiversity’s contribution to human welfare has become a key argument for maintaining and enhancing biodiversity in managed ecosystems. The functional relationship between biodiversity (b) and economic value (V) is, however, insufficiently understood, despite the premise of a positive-concave bV relationship that dominates scientific and political arenas. Here, we review how individual links between biodiversity, ecosystem functions (F), and services affect resulting bV relationships. Our findings show that bV relationships are more variable, also taking negative-concave/convex or strictly concave and convex forms. This functional form is driven not only by the underlying bF relationship but also by the number and type of ecosystem services and their potential trade-offs considered, the effects of inputs, and the type of utility function used to represent human preferences. Explicitly accounting for these aspects will enhance the substance and coverage of future valuation studies and allow more nuanced conclusions, particularly for managed ecosystems

Structural and magnetic properties of an InGaAs/Fe3_3Si superlattice in cylindrical geometry

The structure and the magnetic properties of an InGaAs/Fe3Si superlattice in a cylindrical geometry are investigated by electron microscopy techniques, x-ray diffraction and magnetometry. To form a radial superlattice, a pseudomorphic InGaAs/Fe3As bilayer has been released from its substrate self-forming into a rolled-up microtube. Oxide-free interfaces as well as areas of crystalline bonding are observed and an overall lattice mismatch between succeeding layers is determined. The cylindrical symmetry of the final radial superlattice shows a significant effect on the magnetization behavior of the rolled-up layers

Coupling FEM, Bloch Waves and TMM in Meta Poroelastic Laminates

The propagation of airborne plane waves in the pres- ence of a meta poroelastic laminate, that is a poroelas- tic matrix coated with thin elastic layers at its facings 5 and periodically-embedded with inclusions, is studied. Using the Finite Element Method (FEM) only would result in a drastic increase of the degrees of freedom due to the fine mesh required to account for the very thin coatings. Here, the approach relies on: the Bloch 10 wave expansion of the fields in air; the modal Trans- fer Matrix Method to account for the coatings; and the coupling with the FEM model of the poroelas- tic matrix and the resonant inclusions. The model is developed for reflection and transmission problems 15 and it can account for coatings with multiple layers. The procedure induces the addition of the Bloch co- efficients in the FEM’s linear system at a negligible additional computational cost. It is applied to the meta poroelastic laminates with poroelastic inclusions 20 and rubber shell inclusions. The results are compared with those from the Multiple Scattering Theory and an excellent agreement between the methods is found. The approach offers a numerically-efficient way to ac- count for coatings applied to meta poroelastic layers, 25 and finds applications in industrial prototypes where coatings are widely used

Observation of an Excited Bc+ State

Using pp collision data corresponding to an integrated luminosity of 8.5 fb-1 recorded by the LHCb experiment at center-of-mass energies of s=7, 8, and 13 TeV, the observation of an excited Bc+ state in the Bc+π+π- invariant-mass spectrum is reported. The observed peak has a mass of 6841.2±0.6(stat)±0.1(syst)±0.8(Bc+) MeV/c2, where the last uncertainty is due to the limited knowledge of the Bc+ mass. It is consistent with expectations of the Bc∗(2S31)+ state reconstructed without the low-energy photon from the Bc∗(1S31)+→Bc+γ decay following Bc∗(2S31)+→Bc∗(1S31)+π+π-. A second state is seen with a global (local) statistical significance of 2.2σ (3.2σ) and a mass of 6872.1±1.3(stat)±0.1(syst)±0.8(Bc+) MeV/c2, and is consistent with the Bc(2S10)+ state. These mass measurements are the most precise to date

Measurement of the inelastic pp cross-section at a centre-of-mass energy of 13TeV

The cross-section for inelastic proton-proton collisions at a centre-of-mass energy of 13TeV is measured with the LHCb detector. The fiducial cross-section for inelastic interactions producing at least one prompt long-lived charged particle with momentum p > 2 GeV/c in the pseudorapidity range 2 < η < 5 is determined to be ϭ acc = 62:2 ± 0:2 ± 2:5mb. The first uncertainty is the intrinsic systematic uncertainty of the measurement, the second is due to the uncertainty on the integrated luminosity. The statistical uncertainty is negligible. Extrapolation to full phase space yields the total inelastic proton-proton cross-section ϭ inel = 75:4 ± 3:0 ± 4:5mb, where the first uncertainty is experimental and the second due to the extrapolation. An updated value of the inelastic cross-section at a centre-of-mass energy of 7TeV is also reported

Impact of Sarcoplasmic Reticulum Calcium Release on Calcium Dynamics and Action Potential Morphology in Human Atrial Myocytes: A Computational Study

Electrophysiological studies of the human heart face the fundamental challenge that experimental data can be acquired only from patients with underlying heart disease. Regarding human atria, there exist sizable gaps in the understanding of the functional role of cellular Ca2+ dynamics, which differ crucially from that of ventricular cells, in the modulation of excitation-contraction coupling. Accordingly, the objective of this study was to develop a mathematical model of the human atrial myocyte that, in addition to the sarcolemmal (SL) ion currents, accounts for the heterogeneity of intracellular Ca2+ dynamics emerging from a structurally detailed sarcoplasmic reticulum (SR). Based on the simulation results, our model convincingly reproduces the principal characteristics of Ca2+ dynamics: 1) the biphasic increment during the upstroke of the Ca2+ transient resulting from the delay between the peripheral and central SR Ca2+ release, and 2) the relative contribution of SL Ca2+ current and SR Ca2+ release to the Ca2+ transient. In line with experimental findings, the model also replicates the strong impact of intracellular Ca2+ dynamics on the shape of the action potential. The simulation results suggest that the peripheral SR Ca2+ release sites define the interface between Ca2+ and AP, whereas the central release sites are important for the fire-diffuse-fire propagation of Ca2+ diffusion. Furthermore, our analysis predicts that the modulation of the action potential duration due to increasing heart rate is largely mediated by changes in the intracellular Na+ concentration. Finally, the results indicate that the SR Ca2+ release is a strong modulator of AP duration and, consequently, myocyte refractoriness/excitability. We conclude that the developed model is robust and reproduces many fundamental aspects of the tight coupling between SL ion currents and intracellular Ca2+ signaling. Thus, the model provides a useful framework for future studies of excitation-contraction coupling in human atrial myocytes

Updated Determination of D⁰–D¯⁰Mixing and CP Violation Parameters with D⁰→K⁺π⁻ Decays

We report measurements of charm-mixing parameters based on the decay-time-dependent ratio of D⁰→K⁺π⁻ to D⁰→K⁻π⁺ rates. The analysis uses a data sample of proton-proton collisions corresponding to an integrated luminosity of 5.0  fb⁻¹ recorded by the LHCb experiment from 2011 through 2016. Assuming charge-parity (CP) symmetry, the mixing parameters are determined to be x′²=(3.9±2.7)×10⁻⁵, y′=(5.28±0.52)×10⁻³, and R[subscript D]=(3.454±0.031)×10⁻³. Without this assumption, the measurement is performed separately for D⁰ and D[over ¯]⁰ mesons, yielding a direct CP-violating asymmetry A[subscript D]=(-0.1±9.1)×10⁻³, and magnitude of the ratio of mixing parameters 1.00<|q/p|<1.35 at the 68.3% confidence level. All results include statistical and systematic uncertainties and improve significantly upon previous single-measurement determinations. No evidence for CP violation in charm mixing is observed

Measurement of branching fractions of charmless four-body Λ_b ⁰ and Ξ_b ⁰ decays

A search for charmless four-body decays of Λb 0 and Ξb 0 baryons with a proton and three charged mesons (either kaons or pions) in the final state is performed. The data sample used was recorded in 2011 and 2012 with the LHCb experiment and corresponds to an integrated luminosity of 3 fb−1. Six decay modes are observed, among which Λb 0 → pK−π+π−,Λb 0 → pK−K+K−,Ξb 0 → pK−π+π− and Ξb 0 → pK−π+K− are established for the first time. Their branching fractions (including the ratio of hadronisation fractions in the case of the Ξb 0 baryon) are determined relative to the Λb 0 → Λc +π− decay.[Figure not available: see fulltext.].</p

Direct photon production at LHCb

At small Bjorken-x, the large gluon number density in the nucleon leads to gluon recombination competing with gluon splitting, which could result in saturation of the gluon PDF. This gluon saturation has yet to be conclusively observed. Direct photon production provides sensitivity to gluon densities in protons and nuclei, and the forward acceptance of LHCb detector allows for measurements of this process at low Bjorken-x, providing an ideal probe of saturation effects. Progress towards the measurement of forward direct photon production using the LHCb detector is presented