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Early detection of inflammatory arthritis (IA) is critical to efficient and accurate hospital referral triage for timely treatment and preventing the deterioration of the IA disease course, especially under limited healthcare resources. The manual assessment process is the most common approach in practice for the early detection of IA, but it is extremely labor-intensive and inefficient. A large amount of clinical information needs to be assessed for every referral from General Practice (GP) to the hospitals. Machine learning shows great potential in automating repetitive assessment tasks and providing decision support for the early detection of IA. However, most machine learning-based methods for IA detection rely on blood testing results. But in practice, blood testing data is not always available at the point of referrals, so we need methods to leverage multimodal data such as semi-structured and unstructured data for early detection of IA. In this research, we present fusion and ensemble learning-based methods using multimodal data to assist decision-making in the early detection of IA, and a conformal prediction-based method to quantify the uncertainty of the prediction and detect any unreliable predictions. To the best of our knowledge, our study is the first attempt to utilize multimodal data to support the early detection of IA from GP referrals., Comment: We found some issues in data preprocessing, which will impact the final result. Therefore we would like to withdraw the paper

We present the optical optimization of an optomechanical device based on a suspended InP membrane patterned with a 2D near-wavelength grating (NWG) based on a 2D photonic-crystal geometry. We first identify by numerical simulation a set of geometrical parameters providing a reflectivity higher than 99.8 % over a 50-nm span. We then study the limitations induced by the finite value of the optical waist and lateral size of the NWG pattern using different numerical approaches. The NWG grating, pierced in a suspended InP 265 nm-thick membrane, is used to form a compact microcavity involving the suspended nano-membrane as end mirror. The resulting cavity has a waist size smaller than 10 $\mu$m and a finesse in the 200 range. It is used to probe the Brownian motion of the mechanical modes of the nanomembrane.

Optomechanical systems close to their quantum ground state and nonlinear nanoelectromechanical systems are two hot topics of current physics research. As high-reflectivity and low mass are crucial features to improve optomechanical coupling towards the ground state, we have designed, fabricated and characterized photonic crystal nanomembranes, at the crossroad of both topics. Here we demonstrate a number of nonlinear effects with these membranes. We first characterize the nonlinear behavior of a single mechanical mode and we demonstrate its nonlocal character by monitoring the subsequent actuation-related frequency shift of a different mode. We then proceed to study the underlying nonlinear dynamics, both by monitoring the phase-space trajectory of the free resonator and by characterizing the mechanical response in presence of a strong pump excitation. We observe in particular the frequency evolution during a ring-down oscillation decay, and the emergence of a phase conjugate mechanical response to a weaker probe actuation. Our results are crucial to understand the full nonlinear features of the PhC membranes, and possibly to look for nonlinear signatures of the quantum dynamics.

We have designed photonic crystal suspended membranes with optimized optical and mechanical properties for cavity optomechanics. Such resonators sustain vibration modes in the megahertz range with quality factors of a few thousand. Thanks to a two-dimensional square lattice of holes, their reflectivity at normal incidence at 1064 nm reaches values as high as 95%. These two features, combined with the very low mass of the membrane, open the way to the use of such periodic structures as deformable end-mirrors in Fabry-Perot cavities for the investigation of cavity optomechanical effects

A composition analysis of KASCADE air shower data is performed by means of unfolding the two-dimensional frequency spectrum of electron and muon numbers. Aim of the analysis is the determination of energy spectra for elemental groups representing the chemical composition of primary cosmic rays. Since such an analysis depends crucially on simulations of air showers the two different hadronic interaction models QGSJet and SIBYLL are used for their generation. The resulting primary energy spectra show that the knee in the all particle spectrum is due to a steepening of the spectra of light elements but, also, that neither of the two simulation sets is able to describe the measured data consistently over the whole energy range with discrepancies appearing in different energy regions., Comment: 39 pages, accepted for publication in Astropart. Phys

The geometric distribution of high-energy hadrons >100 GeV in shower cores measured with the KASCADE calorimeter is analyzed. The data are checked for sensitivity to hadronic interaction features and indications of new physics as discussed in the literature. The angular correlation of the most energetic hadrons and in particular the fraction of events with hadrons being aligned are quantified by means of the commonly used parameter lambda_4. The analysis shows that the observed lambda_4 distribution is compatible with that predicted by simulations and is not linked to an angular correlation from hadronic jet production at high energy. Another parameter, d_4^max, describing distances between hadrons measured in the detector, is found to be sensitive both to the transverse momenta in secondary hadron production and the primary particle type. Transverse momenta in high-energy hadron interactions differing by a factor two or more from what is assumed in the standard simulations are disfavoured by the measured d_4^max distribution., Comment: 8 pages, 9 figures; accepted for publication by Phys. Rev. D

KASCADE is a multi-detector setup to get redundant information on single air shower basis. The information is used to perform multiparameter analyses to solve the threefold problem of the reconstruction of (i)the unknown primary energy, (ii) the primary mass, and (iii) to quantify the characteristics of the hadronic interactions in the air-shower development. In this talk recent results of the KASCADE data analyses are summarized concerning cosmic ray anisotropy studies, determination of flux spectra for different primary mass groups, and approaches to test hadronic interaction models. Neither large scale anisotropies nor point sources were found in the KASCADE data set. The energy spectra of the light element groups result in a knee-like bending and a steepening above the knee. The topology of the individual knee positions shows a dependency on the primary particle. Though no hadronic interaction model is fully able to describe the multi-parameter data of KASCADE consistently, the more recent models or improved versions of older models reproduce the data better than few years ago., Comment: to appear in Nucl. Phys. B (Proc. Suppl.), Proc. of the XIII ISVHECRI, Pylos 2004 - with a better quality of the figures

KASCADE-Grande is the extension of the multi-detector setup KASCADE to cover a primary cosmic ray energy range from 100 TeV to 1 EeV. The enlarged EAS experiment provides comprehensive observations of cosmic rays in the energy region around the knee. Grande is an array of 700 x 700 sqm equipped with 37 plastic scintillator stations sensitive to measure energy deposits and arrival times of air shower particles. LOPES is a small radio antenna array to operate in conjunction with KASCADE-Grande in order to calibrate the radio emission from cosmic ray air showers. Status and capabilities of the KASCADE-Grande experiment and the LOPES project are presented., Comment: To appear in Nuclear Physics B, Proceedings Supplements, as part of the volume for the CRIS 2004, Cosmic Ray International Seminar: GZK and Surroundings

The flux of cosmic-ray induced single hadrons near sea level has been measured with the large hadron calorimeter of the KASCADE experiment. The measurement corroborates former results obtained with detectors of smaller size if the enlarged veto of the 304 m^2 calorimeter surface is encounted for. The program CORSIKA/QGSJET is used to compute the cosmic-ray flux above the atmosphere. Between E_0=300 GeV and 1 PeV the primary proton spectrum can be described with a power law parametrized as dJ/dE_0=(0.15+-0.03)*E_0^{-2.78+-0.03} m^-2 s^-1 sr^-1 TeV^-1. In the TeV region the proton flux compares well with the results from recent measurements of direct experiments., Comment: 13 pages, accepted by Astrophysical Journal

A survey of the northern hemisphere for astrophysical point sources with continuous emission of high-energy cosmic rays is presented. Around 47 Mio extensive air showers with primary energies above $\approx$ 300 TeV measured by the KASCADE detector field are selected for this analysis. Besides the sky survey, a search for signal excess in the region of the galactic plane and of selected point source candidates has been performed. There is no evidence for any significant excess. This is valid for an analysis of all recorded showers as well as for a data set enhanced in gamma-ray induced showers. An upper flux limit of around $3\times 10^{-10}$ m$^{-2}$s$^{-1}$ for a steady point source that transits the zenith is obtained. Additionally, the distribution of the arrival directions of extensive air showers with energies above 80 PeV were studied by an autocorrelation analysis., Comment: accepted by The Astrophysical Journal

The results of an analysis of the large scale anisotropy of cosmic rays in the PeV range are presented. The Rayleigh formalism is applied to the right ascension distribution of extensive air showers measured by the KASCADE experiment.The data set contains about 10^8 extensive air showers in the energy range from 0.7 to 6 PeV. No hints for anisotropy are visible in the right ascension distributions in this energy range. This accounts for all showers as well as for subsets containing showers induced by predominantly light respectively heavy primary particles. Upper flux limits for Rayleigh amplitudes are determined to be between 10^-3 at 0.7 PeV and 10^-2 at 6 PeV primary energy., Comment: accepted by The Astrophysical Journal

The KASCADE experiment measures a high number of EAS observables with a large degree of sampling of the electron-photon, muon, and hadron components. It provides accurate data for an event-by-event analysis of the primary cosmic ray flux in the energy range around the knee. The possibility of selecting samples of enriched proton and iron induced extensive air showers by applying the statistical techniques of multivariate analyses is scrutinized using detailed Monte Carlo simulations of three different primaries. The purity and efficiency of the proton and iron classified events is investigated. After obtaining enriched samples from the measured data by application of the procedures the reconstructed number of hadrons, hadronic energy and other parameters are investigated in the primary energy range 1-10 PeV. By comparing these shower parameters for purified proton and iron events, respectively, with simulated distributions an attempt is made to check the validity of strong interaction models at high energies., Comment: 20 pages, accepted for publication in Astroparticle Physics

The attenuation of the electron shower size beyond the shower maximum is studied with the KASCADE extensive air shower experiment in the primary energy range of about $10^{14}-10^{16}$ eV. Attenuation and absorption lengths are determined by applying different approaches, including the method of constant intensity, the decrease of the flux of extensive air showers with increasing zenith angle, and its variation with ground pressure. We observe a significant dependence of the results on the applied method. The determined values of the attenuation length ranges from 175 to 196 g/cm$^2$ and of the absorption length from 100 to 120 g/cm$^2$. The origin of these differences is discussed emphasizing the influence of intrinsic shower fluctuations., Comment: 19 pages, 11 figures, accepted for publication in Astroparticle Physics

An analysis of muon and hadron rates observed in the central detector of the KASCADE experiment has been carried out. The data are compared to CORSIKA simulations employing the high-energy hadronic interaction models QGSJET, DPMJET, HDPM, SIBYLL, and VENUS. In addition, first results with the new hadronic interaction model neXus 2 are discussed. Differences of the model predictions, both among each other and when confronted with measurements, are observed. The hadron rates mainly depend on the inelastic cross-section and on the contribution of diffraction dissociation. The discrepancy between simulations and measurements at low primary energies around 5 TeV can be reduced by increasing the non-diffractive part of the inelastic cross-section of nucleon-air interactions. Examination of hadron multiplicities points towards harder spectra of secondary pions and kaons needed in the calculations., Comment: 14 pages, 7 figures, corresponding author: M. Risse, accepted for publication in J. Phys. G: Nucl. Part. Phys

Frequency distributions of local muon densities in high-energy extensive air-showers (EAS) are presented as signature of the primary cosmic ray energy spectrum in the knee region. Together with the gross shower variables like shower core position, angle of incidence, and the shower sizes, the KASCADE experiment is able to measure local muon densities for two different muon energy thresholds. The spectra have been reconstructed for various core distances, as well as for particular subsamples, classified on the basis of the shower size ratio N_mu/N_e. The measured density spectra of the total sample exhibit clear kinks reflecting the knee of the primary energy spectrum. While relatively sharp changes of the slopes are observed in the spectrum of EAS with small values of the shower size ratio, no such feature is detected at EAS of large N_mu/N_e ratio in the energy range of 1--10 PeV. Comparing the spectra for various thresholds and core distances with detailed Monte Carlo simulations the validity of EAS simulations is discussed., Comment: 21 pages,12 figures, accepted at Astroparticle Physics

The experiment KASCADE observes simultaneously the electron-photon, muon, and hadron components of high-energy extensive air showers (EAS). The analysis of EAS observables for an estimate of energy and mass of the primary particle invokes extensive Monte Carlo simulations of the EAS development for preparing reference patterns. The present studies utilize the air shower simulation code CORSIKA with the hadronic interaction models VENUS, QGSJet and Sibyll, including simulations of the detector response and efficiency. By applying non-parametric techniques the measured data have been analyzed in an event-by-event mode and the mass and energy of the EAS inducing particles are reconstructed. Special emphasis is given to methodical limitations and the dependence of the results on the hadronic interaction model used. The results obtained from KASCADE data reproduce the knee in the primary spectrum, but reveal a strong model dependence. Owing to the systematic uncertainties introduced by the hadronic interaction models no strong change of chemical composition can be claimed in the energy range around the knee., Comment: 28 pages, 13 figures, Accepted for publication in Astroparticle Physics

Measurements of electron, muon, and hadron lateral distributions of extensive air showers as recorded by the KASCADE experiment are presented. The data cover the energy range from about 5x10^14 eV up to almost 10^17 eV and extend from the inner core region to distances of 200 m. The electron and muon distributions are corrected for mutual contaminations by taking into account the detector properties in the experiment. All distributions are well described by NKG-functions. The scale radii describing the electron and hadron data best are approx. 30 m and 10 m, respectively. We discuss the correlation between scale radii and `age' parameter as well as their dependence on shower size, zenith angle, and particle energy threshold., Comment: 28 pages, 14 figures, Accepted for publication in Astroparticle Physics

The main goals of the KASCADE (KArlsruhe Shower Core and Array DEtector) experiment are the determination of the energy spectrum and elemental composition of the charged cosmic rays in the energy range around the knee at ca. 5 PeV. Due to the large number of measured observables per single shower a variety of different approaches are applied to the data, preferably on an event-by-event basis. First results are presented and the influence of the high-energy interaction models underlying the analyses is discussed., Comment: 3 pages, 3 figures included, to appear in the TAUP 99 Proceedings, Nucl. Phys. B (Proc. Suppl.), ed. by M. Froissart, J. Dumarchez and D. Vignaud

Using the large hadron calorimeter of the KASCADE experiment, hadronic cores of extensive air showers have been studied. The hadron lateral and energy distributions have been investigated in order to study the reliability of the shower simulation program CORSIKA with respect to particle transport, decays, treatment of low-energy particles, etc. A good description of the data has been found at large distances from the shower core for several interaction models. The inner part of the hadron distribution, on the other hand, reveals pronounced differences among interaction models. Several hadronic observables are compared with CORSIKA simulations using the QGSJET, VENUS and SIBYLL models. QGSJET reproduces the hadronic distributions best. At the highest energy, in the 10 PeV region, however, none of these models can describe the experimental data satisfactorily. The expected number of hadrons in a shower is too large compared to the observed number, when the data are classified according to the muonic shower size., Comment: submited to Journal of Physics G