pinecone/core-2020-05-10-deduplication huggingface dataset:
Dynamics of monopole walls

AbstractThe moduli space of centred Bogomolny–Prasad–Sommerfield 2-monopole fields is a 4-dimensional manifold M with a natural metric, and the geodesics on M correspond to slow-motion monopole dynamics. The best-known case is that of monopoles on R3, where M is the Atiyah–Hitchin space. More recently, the case of monopoles periodic in one direction (monopole chains) was studied a few years ago. Our aim in this note is to investigate M for doubly-periodic fields, which may be visualized as monopole walls. We identify some of the geodesics on M as fixed-point sets of discrete symmetries, and interpret these in terms of monopole scattering and bound orbits, concentrating on novel features that arise as a consequence of the periodicity
Casimir–Polder potential for a metallic cylinder in cosmic string spacetime

AbstractCasimir–Polder potential is investigated for a polarizable microparticle in the geometry of a straight cosmic string with a metallic cylindrical shell. The electromagnetic field Green tensor is evaluated on the imaginary frequency axis. The expressions for the Casimir–Polder potential is derived in the general case of anisotropic polarizability for the both interior and exterior regions of the shell. The potential is decomposed into pure string and shell-induced parts. The latter dominates for points near the shell, whereas the pure string part is dominant near the string and at large distances from the shell. For the isotropic case and in the region inside the shell the both pure string and shell-induced parts in the Casimir–Polder force are repulsive with respect to the string. In the exterior region the shell-induced part of the force is directed toward the cylinder whereas the pure string part remains repulsive with respect to the string. At large distances from the shell the total force is repulsive
Single-Molecule Folding Mechanisms of the apo- and Mg2+-Bound States of Human Neuronal Calcium Sensor-1

AbstractNeuronal calcium sensor-1 (NCS-1) is the primordial member of a family of proteins responsible primarily for sensing changes in neuronal Ca2+ concentration. NCS-1 is a multispecific protein interacting with a number of binding partners in both calcium-dependent and independent manners, and acting in a variety of cellular processes in which it has been linked to a number of disorders such as schizophrenia and autism. Despite extensive studies on the Ca2+-activated state of NCS proteins, little is known about the conformational dynamics of the Mg2+-bound and apo states, both of which are populated, at least transiently, at resting Ca2+ conditions. Here, we used optical tweezers to study the folding behavior of individual NCS-1 molecules in the presence of Mg2+ and in the absence of divalent ions. Under tension, the Mg2+-bound state of NCS-1 unfolds and refolds in a three-state process by populating one intermediate state consisting of a folded C-domain and an unfolded N-domain. The interconversion at equilibrium between the different molecular states populated by NCS-1 was monitored in real time through constant-force measurements and the energy landscapes underlying the observed transitions were reconstructed through hidden Markov model analysis. Unlike what has been observed with the Ca2+-bound state, the presence of Mg2+ allows both the N- and C-domain to fold through all-or-none transitions with similar refolding rates. In the absence of divalent ions, NCS-1 unfolds and refolds reversibly in a two-state reaction involving only the C-domain, whereas the N-domain has no detectable transitions. Overall, the results allowed us to trace the progression of NCS-1 folding along its energy landscapes and provided a solid platform for understanding the conformational dynamics of similar EF-hand proteins
Energy dependence of forward 1S0 diproton production in the pp→ppπ0 reaction

AbstractThe pp→{pp}sπ0 differential cross section has been measured with the ANKE spectrometer at COSY-Jülich for seven proton beam energies Tp between 0.51 and 1.97 GeV. By selecting proton pairs with an excitation energy of less than 3 MeV it is ensured that the final {pp}s system is in the S01 state. In the measured region of θppcm≲18°, the data reveal a forward dip for Tp⩽1.4 GeV whereas a forward peaking is seen at 1.97 GeV. The energy dependence of the forward cross section shows a broad peak in the 0.6–0.8 GeV region, probably associated with Δ(1232) excitation, and a minimum at 1.4 GeV. Some of these features are similar to those observed for the spin–isospin partner reaction, pp→dπ+. However, the ratio of the forward differential cross sections of the two reactions shows a significant suppression of single pion production associated with a spin-singlet final nucleon pair
Above ground perennial plant biomass across an altitudinal and land-use gradient in Namaqualand, South Africa

AbstractThis study set out to generate estimates of the standing perennial biomass for six different vegetation types, and associated upland and lowland habitats, across the altitudinal gradient presented by the Kamiesberg mountain range in the Namaqualand region of the Northern Cape Province of South Africa. Volume-biomass regressions, established for 94 perennial species accounting for 70–80% of the plant cover, were used to generate these estimations. Comparisons to other studies give similar findings, corroborating the method adopted. Biomass was found to vary significantly in relation to the altitudinal, and associated rainfall, gradient, as well as by habitat type where the rocky uplands have considerably more biomass that the sandy lowland habitats. An examination of the impact of sustained heavy grazing associated with a communal rangeland on this standing perennial biomass, showed a significant decrease in on the lowland habitats. This loss in biomass is principally of palatable species, with no evidence of a response in terms of perennial biomass. These findings point to degradation on the lowland habitats of the communal rangeland, with negative consequences for livestock farmers in the region
A scheme for assessing the performance characteristics of small field-of-view gamma cameras

AbstractExisting protocols for assessing the performance characteristics of large field-of-view (LFOV) gamma cameras can be inappropriate and require modification for use with small field-of-view (SFOV) gamma camera systems. This communication proposes a generic scheme suitable for evaluating the performance characteristics of SFOV gamma cameras, based on modifications to the standard procedures of NEMA NU1-2007. Key differences in methodology between tests for LFOV and SFOV gamma cameras are highlighted along with the rationale for these changes. It is envisaged that this scheme will provide more appropriate methods for equipment characterisation, ensuring quality and consistency for all SFOV cameras
Costs and Outcomes of Increasing Access to Bariatric Surgery: Cohort Study and Cost-Effectiveness Analysis Using Electronic Health Records

AbstractObjectivesTo estimate costs and outcomes of increasing access to bariatric surgery in obese adults and in population subgroups of age, sex, deprivation, comorbidity, and obesity category.MethodsA cohort study was conducted using primary care electronic health records, with linked hospital utilization data, for 3,045 participants who underwent bariatric surgery and 247,537 participants who did not undergo bariatric surgery. Epidemiological analyses informed a probabilistic Markov model to compare bariatric surgery, including equal proportions with adjustable gastric banding, gastric bypass, and sleeve gastrectomy, with standard nonsurgical management of obesity. Outcomes were quality-adjusted life-years (QALYs) and net monetary benefits at a threshold of £30,000 per QALY.ResultsIn a UK population of 250,000 adults, there may be 7,163 people with morbid obesity including 1,406 with diabetes. The immediate cost of 1,000 bariatric surgical procedures is £9.16 million, with incremental discounted lifetime health care costs of £15.26 million (95% confidence interval £15.18–£15.36 million). Patient-years with diabetes mellitus will decrease by 8,320 (range 8,123–8,502). Incremental QALYs will increase by 2,142 (range 2,032–2,256). The estimated cost per QALY gained is £7,129 (range £6,775–£7,506). Net monetary benefits will be £49.02 million (range £45.72–£52.41 million). Estimates are similar for subgroups of age, sex, and deprivation. Bariatric surgery remains cost-effective if the procedure is twice as costly, or if intervention effect declines over time.ConclusionsDiverse obese individuals may benefit from bariatric surgery at acceptable cost. Bariatric surgery is not cost-saving, but increased health care costs are exceeded by health benefits to obese individuals
Electroweak two-loop contribution to the mass splitting within a new heavy SU(2)L fermion multiplet

AbstractNew heavy particles in an SU(2)L multiplet, sometimes introduced in extensions of the standard model, have highly degenerate tree-level mass M if their couplings to the Higgs bosons are very small or forbidden. However, loop corrections may generate the gauge-symmetry-breaking mass splitting within the multiplet, which does not vanish in the large M limit due to the threshold singularity. We calculate the electroweak contribution to the mass splitting for a heavy fermion multiplet, to the two-loop order. Numerically, two-loop electroweak contributions are typically O (MeV)
Validating Behavioral Component Interfaces in Rewriting Logic

AbstractMany distributed applications can be understood in terms of components interacting in an open environment such as the Internet. Open environments are subject to change in unpredictable ways, as other applications may arrive, evolve, or disappear. In order to validate components in such environments, it can be useful to build a simulation environment which reflects this highly unpredictable behavior. In this paper, the validation of components with respect to behavioral interfaces is considered. Behavioral interfaces specify semantic requirements on the observable behavior of components, expressed in an assume-guarantee style. In our approach, a rewriting logic model is transparently extended with the history of all observable communication, and metalevel strategies are used to guide the simulation of environment behavior. Over-specification of the environment is avoided by allowing arbitrary environment behavior within the bounds of the assumption on observable behavior, while the component is validated with respect to the guarantee of the behavioral interface
K0⁎(800) as a companion pole of K0⁎(1430)

AbstractWe study the light scalar sector up to 1.8 GeV by using a quantum field theoretical approach which includes a single kaonic state in a Lagrangian with both derivative and non-derivative interactions. By performing a fit to πK phase shift data in the I=1/2, J=0 channel, we show that K0⁎(800) (or κ) emerges as a dynamically generated companion pole of K0⁎(1430). This is a result of investigating quantum fluctuations with one kaon and one pion circulating in the loops dressing K0⁎(1430). We determine the position of the poles on the complex plane in the context of our approach: for K0⁎(1430) we get (1.413±0.002)−i(0.127±0.003) (in GeV), while for κ we get (0.746±0.019)−i(0.262±0.014) (in GeV). The model-dependence of these results and related uncertainties are discussed in the paper. A large-Nc study confirms that K0⁎(1430) is predominantly a quarkonium and that K0⁎(800) is a molecular-like dynamically generated state
Effective equidistribution and the Sato–Tate law for families of elliptic curves

AbstractTextExtending recent work of others, we provide effective bounds on the family of all elliptic curves and one-parameter families of elliptic curves modulo p (for p prime tending to infinity) obeying the Sato–Tate law. We present two methods of proof. Both use the framework of Murty and Sinha (2009) [MS]; the first involves only knowledge of the moments of the Fourier coefficients of the L-functions and combinatorics, and saves a logarithm, while the second requires a Sato–Tate law. Our purpose is to illustrate how the caliber of the result depends on the error terms of the inputs and what combinatorics must be done.VideoFor a video summary of this paper, please click here or visit http://www.youtube.com/watch?v=faW2iDpe5IE
Photoionization models of the CALIFA HII regions I. Hybrid models

Photoionization models of HIT regions require as input a description of the ionizing spectral energy distribution (SED) and of the gas distribution, in terms of ionization parameter U and chemical abundances (e.g., O/H and N/O). A strong degeneracy exists between the hardness of the SED and U, which in turn leads to high uncertainties in the determination of the other parameters, including abundances. One way to resolve the degeneracy is to fix one of the parameters using additional information. For each of the 20 000 sources of the CALIFA HIT regions catalog, a grid of photoionization models is computed assuming the ionizing SED to be described by the underlying stellar population obtained from spectral synthesis modeling. The ionizing SED is then defined as the sum of various stellar bursts of different ages and metallicities. This solves the degeneracy between the shape of the ionizing SED and U. The nebular metallicity (associated with O/H) is defined using the classical strong line method O3N2 (which gives our models the status of "hybrids"). The remaining free parameters are the abundance ratio N/O and the ionization parameter U, which are determined by looking for the model fitting [N II]/H alpha and [O III]/H beta. The models are also selected to fit [O II]/H beta. This process leads to a set of 3200 models that reproduce the three observations simultaneously. We find that the regions associated with young stellar bursts (i.e., ionized by OB stars) are affected by leaking of ionizing photons, the proportion of escaping photons having a median of 80%. The set of photoionization models satisfactorily reproduces the electron temperature derived from the [O III]lambda 4363/5007 line ratio. We determine new relations between the nebular parameters, like the ionization parameter U and the [OH]/[ III] or [S II]/[S III] line ratios. A new relation between N/O and O/H is obtained, mostly compatible with previous empirical determinations (and not with previous results obtained using photoionization models). A new relation between U and O/H is also determined. All the models are publicly available on the Mexican Million Models database 3MdB
Lasing by driven atoms-cavity system in collective strong coupling
  regime

The interaction of laser cooled and trapped atoms with resonant light is
limited by the linewidth of the excited state of the atom. Another precise
optical oscillator is an optical Fabry-P\'erot cavity. The combining of cold
atoms with optical oscillators is emerging as an area with great potential for
precision measurements and the creation of versatile quantum optics systems.
Here we show that when driven atoms are in the collectively strongly coupled
regime with the cavity, exhibiting vacuum Rabi splitting (VRS), lasing is
observed for the emitted light, red detuned from atomic transition. This is
demonstrated experimentally by the observation of a lasing threshold,
polarisation purity, mode purity, and line narrowing. The laser is created
spontaneously by the atomic emission into the cavity mode, which stimulates
cavity emission, and is capable of operating continuously without a seed laser.
The gain mechanism is understood by theoretical modelling and illustrates why
the observed lasing is generic to the coupled system. This opens up a range of
possibilities of using the phenomenon for a variety of new measurements.Comment: 12 pages, 7 figure
Exhuming the Meso-Cenozoic Kyrgyz Tianshan and Siberian Altai-Sayan : a review based on low-temperature thermochronology

Thermochronological datasets for the Kyrgyz Tianshan and Siberian Altai-Sayan within Central Asia reveal a punctuated exhumation history during the Meso-Cenozoic. In this paper, the datasets for both regions are collectively reviewed in order to speculate on the links between the Meso-Cenozoic exhumation of the continental Eurasian interior and the prevailing tectonic processes at the plate margins. Whereas most of the thermochronological data across both regions document late Jurassic-Cretaceous regional basement cooling, older landscape relics and dissecting fault zones throughout both regions preserve Triassic and Cenozoic events of rapid cooling, respectively. Triassic cooling is thought to reflect the Qiangtang-Eurasia collision and/or rifting/subsidence in the West Siberian basin. Alternatively, this cooling signal could be related with the terminal terrane-amalgamation of the Central Asian Orogenic Belt. For the Kygyz Tianshan, late Jurassic-Cretaceous regional exhumation and Cenozoic fault reactivations can be linked with specific tectonic events during the closure of the Palaeo-Tethys and Neo-Tethys Oceans, respectively. The effect of the progressive consumption of these oceans and the associated collisions of Cimmeria and India with Eurasia probably only had a minor effect on the exhumation of the Siberian Altai-Sayan. More likely, tectonic forces from the east (present-day coordinates) as a result of the building and collapse of the Mongol-Okhotsk orogen and rifting in the Baikal region shaped the current Siberian Altai-Sayan topography. Although many of these hypothesised links need to be tested further, they allow a first-order insight into the dynamic response and the stress propagation pathways from the Eurasian margin into the continental interior
On pseudo-hyperkähler prepotentials

An explicit surjection from a set of (locally defined) unconstrained holomorphic functions on a certain submanifold of Sp1(ℂ) × ℂ^4n onto the set HK_{p,q} of local isometry classes of real analytic pseudo-hyperkähler metrics of signature (4p, 4q) in dimension 4n is constructed. The holomorphic functions, called prepotentials, are analogues of Kähler potentials for Kähler metrics and provide a complete parameterisation of HK_{p,q}. In particular, there exists a bijection between HKp,q and the set of equivalence classes of prepotentials. This affords the explicit construction of pseudo-hyperkähler metrics from specified prepotentials. The construction generalises one due to Galperin, Ivanov, Ogievetsky, and Sokatchev. Their work is given a coordinate-free formulation and complete, self-contained proofs are provided. The Appendix provides a vital tool for this construction: a reformulation of real analytic G-structures in terms of holomorphic frame fields on complex manifolds
A two-component model for the high-energy variability of blazars.
  Application to PKS 2155-304

We study the production of VHE emission in blazars as a superposition of a
steady component from a baryonic jet and a time- dependent contribution from an
inner e-e+ beam launched by the black hole. Both primary relativistic electrons
and protons are injected in the jet, and the particle distributions along it
are found by solving a one-dimensional transport equation that accounts for
convection and cooling. The short-timescale variability of the emission is
explained by local pair injections in turbulent regions of the inner beam. For
illustration, we apply the model to the case of PKS 2155-304, reproducing a
quiescent state of emission with inverse Compton and synchrotron radiation from
primary electrons, as well as proton-proton interactions in the jet. The latter
also yield an accompanying neutrino flux that could be observed with a new
generation km-scale detector in the northern hemisphere such as KM3NeT.Comment: 9 pages, 12 figures, published in A&A (final version
Effect of handling characteristics on minimum time cornering with torque vectoring

In this paper, the effect of both passive and actively-modified vehicle handling characteristics on minimum time manoeuvring for vehicles with 4-wheel torque vectoring (TV) capability is studied. First, a baseline optimal TV strategy is sought, independent of any causal control law. An optimal control problem (OCP) is initially formulated considering 4 independent wheel torque inputs, together with the steering angle rate, as the control variables. Using this formulation, the performance benefit using TV against an electric drive train with a fixed torque distribution, is demonstrated. The sensitivity of TV-controlled manoeuvre time to the passive understeer gradient of the vehicle is then studied. A second formulation of the OCP is introduced where a closed-loop TV controller is incorporated into the system dynamics of the OCP. This formulation allows the effect of actively modifying a vehicle's handling characteristic via TV on its minimum time cornering performance of the vehicle to be assessed. In particular, the effect of the target understeer gradient as the key tuning parameter of the literature-standard steady-state linear single-track model yaw rate reference is analysed
NLO QCD+EW predictions for HV and HV +jet production including parton-shower effects.

We present the first NLO QCD+EW predictions for Higgs boson production in association with a ℓνℓ or ℓ+ℓ− pair plus zero or one jets at the LHC. Fixed-order NLO QCD+EW calculations are combined with a QCD+QED parton shower using the recently developed resonance-aware method in the POWHEG framework. Moreover, applying the improved MiNLO technique to Hℓνℓ +jet and Hℓ+ℓ− +jet production at NLO QCD+EW, we obtain predictions that are NLO accurate for observables with both zero or one resolved jet. This approach permits also to capture higher-order effects associated with the interplay of EW corrections and QCD radiation. The behavior of EW corrections is studied for various kinematic distributions, relevant for experimental analyses of Higgsstrahlung processes at the 13 TeV LHC. Exact NLO EW corrections are complemented with approximate analytic formulae that account for the leading and next-to-leading Sudakov logarithms in the high-energy regime. In the tails of transverse-momentum distributions, relevant for analyses in the boosted Higgs regime, the Sudakov approximation works well, and NLO EW effects can largely exceed the ten percent level. Our predictions are based on the POWHEG BOX RES+OpenLoops framework in combination with the Pythia 8.1 parton shower
The determinants of co-inventor tie formation: proximity and network dynamics

This paper investigates the determinants of co-inventor tie formation using micro-data on genomic patents from 1990 to 2006 in France. We consider in a single analysis the relational and proximity perspectives that are usually treated separately. In order to do so, we analyse the determinants of network ties that occur within existing components and between two distinct components (i.e. bridging ties). We test the argument that formation of these two different types of ties results from distinct strategies in accessing resources. Doing so, we contrast network and proximity determinants of network formation and we investigate if social network allows economic actors to cross over geographical, technological and organizational boundaries.