A geometric construction of traveling waves in a bioremediation.

Bioremediation is a promising technique for cleaning contaminated soil. We study an idealized bioremediation model involving a substrate (contaminant to be removed), electron acceptor (added nutrient), and microorganisms in a one-dimensional soil column. Using geometric singular perturbation theory, we construct traveling waves (TW) corresponding to motion of a biologically active zone, in which the microorganisms consume both substrate and acceptor. For certain values of the parameters, the traveling waves exist on a three-dimensional slow manifold within the five-dimensional phase space. We prove persistence of the slow manifold under perturbation by controlling the nonlinearity via a change of coordinates, and we construct the wave in the transverse intersection of appropriate stable and unstable manifolds in this slow manifold. We study how the TW depends on the half saturation constants and other parameters and investigate numerically a bifurcation in which the TW loses stability to a periodic wav

Quantum State Tomography of Complex Multimode Fields using Array Detectors

We demonstrate that it is possible to use the balanced homodyning with array detectors to measure the quantum state of correlated two-mode signal field. We show the applicability of the method to fields with complex mode functions, thus generalizing the work of Beck (Phys. Rev. Letts. 84, 5748 (2000)) in several important ways. We further establish that, under suitable conditions, array detector measurements from one of the two outputs is sufficient to determine the quantum state of signals. We show the power of the method by reconstructing a truncated Perelomov state which exhibits complicated structure in the joint probability density for the quadratures.Comment: 14 pages text and 3 figures. To be submitted to PR

Laser-induced nonresonant nuclear excitation in muonic atoms

Coherent nuclear excitation in strongly laser-driven muonic atoms is calculated. The nuclear transition is caused by the time-dependent Coulomb field of the oscillating charge density of the bound muon. A closed-form analytical expression for electric multipole transitions is derived and applied to various isotopes; the excitation probabilities are in general very small. We compare the process with other nuclear excitation mechanisms through coupling with atomic shells and discuss the prospects to observe it in experiment.Comment: 7 pages, 5 figure

Direct sampling of exponential phase moments of smoothed Wigner functions

We investigate exponential phase moments of the s-parametrized quasidistributions (smoothed Wigner functions). We show that the knowledge of these moments as functions of s provides, together with photon-number statistics, a complete description of the quantum state. We demonstrate that the exponential phase moments can be directly sampled from the data recorded in balanced homodyne detection and we present simple expressions for the sampling kernels. The phase moments are Fourier coefficients of phase distributions obtained from the quasidistributions via integration over the radial variable in polar coordinates. We performed Monte Carlo simulations of the homodyne detection and we demonstrate the feasibility of direct sampling of the moments and subsequent reconstruction of the phase distribution.Comment: RevTeX, 8 pages, 6 figures, accepted Phys. Rev.

Measurement of the vector analyzing power in elastic electron-proton scattering as a probe of double photon exchange amplitudes

We report the first measurement of the vector analyzing power in inclusive transversely polarized elastic electron-proton scattering at Q^2 = 0.1 (GeV/c)^2 and large scattering angles. This quantity should vanish in the single virtual photon exchange, plane wave impulse approximation for this reaction, and can therefore provide information on double photon exchange amplitudes for electromagnetic interactions with hadronic systems. We find a non-zero value of A=-15.4+/-5.4 ppm. No calculations of this observable for nuclei other than spin 0 have been carried out in these kinematics, and the calculation using the spin orbit interaction from a charged point nucleus of spin 0 cannot describe these data.Comment: 4 pages, 2 figures, submitted to Phys. Rev. Let

Textbook outcome as a composite outcome measure in non-small-cell lung cancer surgery

OBJECTIVES: Quality assessment is an important element in providing surgical cancer care. The main objective of this study was to develop a new composite measure 'textbook outcome', to evaluate and improve quality of surgical care for patients undergoing a resection for non-small-cell lung cancer (NSCLC).METHODS: All patients undergoing an anatomical resection for NSCLC from 2012 to 2016 registered in the nationwide Dutch Lung Cancer Audit were included in an analysis to assess usefulness of a composite measure as a quality indicator. Based on expert opinion, textbook outcome was defined as having a complete resection (negative resection margins and sufficient lymph node dissection), plus no 30-day or in-hospital mortality, no reintervention in 30days, no readmission to the intensive care unit, no prolonged hospital stay (<14days), no hospital readmission after discharge and no major complications. The percentage of patients with a textbook outcome was calculated per hospital. Between-hospital variation in textbook outcome was analysed using case-mix adjustment models.RESULTS: In total, 5513 patients were included in this study. Textbook outcome was achieved in 26.4% of patients. Insufficient lymph node dissection had the most substantial effect on not realizing textbook outcome. If 'sufficient lymph node dissection' was not included as a criterion, textbook outcome would be 60.7%. Case-mix adjusted textbook outcome proportions per hospitals varied between 13.2% and 37.7%.CONCLUSIONS: In contrast to focusing on a single aspect, the composite measure textbook outcome provides insight into comprehensive performance in NSCLC surgery. It can be used to evaluate both individual hospitals and national performance and provides the opportunity to give benchmarked feedback to thoracic surgeons.Thoracic Surger

Multiwavelength studies of MHD waves in the solar chromosphere: An overview of recent results

The chromosphere is a thin layer of the solar atmosphere that bridges the relatively cool photosphere and the intensely heated transition region and corona. Compressible and incompressible waves propagating through the chromosphere can supply significant amounts of energy to the interface region and corona. In recent years an abundance of high-resolution observations from state-of-the-art facilities have provided new and exciting ways of disentangling the characteristics of oscillatory phenomena propagating through the dynamic chromosphere. Coupled with rapid advancements in magnetohydrodynamic wave theory, we are now in an ideal position to thoroughly investigate the role waves play in supplying energy to sustain chromospheric and coronal heating. Here, we review the recent progress made in characterising, categorising and interpreting oscillations manifesting in the solar chromosphere, with an impetus placed on their intrinsic energetics.Comment: 48 pages, 25 figures, accepted into Space Science Review

Modeling the Subsurface Structure of Sunspots

While sunspots are easily observed at the solar surface, determining their subsurface structure is not trivial. There are two main hypotheses for the subsurface structure of sunspots: the monolithic model and the cluster model. Local helioseismology is the only means by which we can investigate subphotospheric structure. However, as current linear inversion techniques do not yet allow helioseismology to probe the internal structure with sufficient confidence to distinguish between the monolith and cluster models, the development of physically realistic sunspot models are a priority for helioseismologists. This is because they are not only important indicators of the variety of physical effects that may influence helioseismic inferences in active regions, but they also enable detailed assessments of the validity of helioseismic interpretations through numerical forward modeling. In this paper, we provide a critical review of the existing sunspot models and an overview of numerical methods employed to model wave propagation through model sunspots. We then carry out an helioseismic analysis of the sunspot in Active Region 9787 and address the serious inconsistencies uncovered by \citeauthor{gizonetal2009}~(\citeyear{gizonetal2009,gizonetal2009a}). We find that this sunspot is most probably associated with a shallow, positive wave-speed perturbation (unlike the traditional two-layer model) and that travel-time measurements are consistent with a horizontal outflow in the surrounding moat.Comment: 73 pages, 19 figures, accepted by Solar Physic