Astrophysical Fluid Dynamics via Direct Statistical Simulation

In this paper we introduce the concept of Direct Statistical Simulation (DSS) for astrophysical flows. This technique may be appropriate for problems in astrophysical fluids where the instantaneous dynamics of the flows are of secondary importance to their statistical properties. We give examples of such problems including mixing and transport in planets, stars and disks. The method is described for a general set of evolution equations, before we consider the specific case of a spectral method optimised for problems on a spherical surface. The method is illustrated for the simplest non-trivial example of hydrodynamics and MHD on a rotating spherical surface. We then discuss possible extensions of the method both in terms of computational methods and the range of astrophysical problems that are of interest.Comment: 26 pages, 11 figures, added clarifying remarks and references, and corrected typos. This version is accepted for publication in The Astrophysical Journa

Predictive value of the Acute Low Back Pain Screening Questionnaire and the Örebro Musculoskeletal Pain Screening Questionnaire for persisting problems

Introduction: A small proportion of individuals with non-specific low back pain (NSLBP) develop persistent problems. Up to 80% of the total costs for NSLBP are owing to chronic NSLBP. Psychosocial factors have been described to be important in the transition from acute to chronic NSLBP. Guidelines recommend the use of the Acute Low Back Pain Screening Questionnaire (ALBPSQ) and the Örebro Musculoskeletal Pain Screening Questionnaire (ÖMPSQ) to identify individuals at risk of developing persistent problems, such as long-term absence of work, persistent restriction in function or persistent pain. These instruments can be used with a cutoff value, where patients with values above the threshold are further assessed with a more comprehensive examination. Methods: We systematically reviewed studies evaluating the accuracy of the ALBPSQ and ÖMPSQ to predict persistent problems. Results: The 13 included studies used different cutoff values for the screening questionnaires ranging from 68 to 147. The pooled sensitivity was 0.59 (0.43-0.74), while the pooled specificity was 0.77 (0.66-0.86). Heterogeneity (I 2) was 90.02% for sensitivity and 95.41% for specificity. Conclusion: Thus, we do not recommend the use of one cutoff value, but the use of a prediction model with all the individual item

Quantification of Volatile Acetone Oligomers Using Ion-Mobility Spectrometry

Background. Volatile acetone is a potential biomarker that is elevated in various disease states. Measuring acetone in exhaled breath is complicated by the fact that the molecule might be present as both monomers and dimers, but in inconsistent ratios. Ignoring the molecular form leads to incorrect measured concentrations. Our first goal was to evaluate the monomer-dimer ratio in ambient air, critically ill patients, and rats. Our second goal was to confirm the accuracy of the combined (monomer and dimer) analysis by comparison to a reference calibration system. Methods. Volatile acetone intensities from exhaled air of ten intubated, critically ill patients, and ten ventilated Sprague-Dawley rats were recorded using ion-mobility spectrometry. Acetone concentrations in ambient air in an intensive care unit and in a laboratory were determined over 24 hours. )e calibration reference was pure acetone vaporized by a gas generator at concentrations from 5 to 45 ppbv (parts per billion by volume). Results. Acetone concentrations in ambient laboratory air were only slightly greater (5.6 ppbv; 95% CI 5.1–6.2) than in ambient air in an intensive care unit (5.1 ppbv; 95% CI 4.4–5.5; p < 0.001). Exhaled acetone concentrations were only slightly greater in rats (10.3 ppbv; 95% CI 9.7–10.9) than in critically ill patients (9.5 ppbv; 95% CI 7.9–11.1; p < 0.001). Vaporization yielded acetone monomers (1.3–5.3 mV) and dimers (1.4–621 mV). Acetone concentrations (ppbv) and corresponding acetone monomer and dimer intensities (mV) revealed a high coefficient of determination (R2 � 0.96). )e calibration curve for acetone concentration (ppbv) and total acetone (monomers added to twice the dimers; mV) was described by the exponential growth 3-parameter model, with an R2 � 0.98. Conclusion. )e ratio of acetone monomer and dimer is inconsistent and varies in ambient air from place-to-place and across individual humans and rats. Monomers and dimers must therefore be considered when quantifying acetone. Combining the two accurately assesses total volatile acetone

Complete Response on Larotrectinib in NTRK2 Fusion-Positive Non-Small Cell Lung Cancer.

In patients with non-small cell lung cancer (NSCLC) harboring a fusion of the neurotrophic receptor kinase (NTRK) gene 1 or 3, treatment with tropomyosin kinase (TRK) inhibitors have shown promising results, however so far no data on efficacy of these agents in patients with NSCLC and NTRK2 fusion are available. We present a case of a female patient with NTRK2-positive NSCLC with a complete ongoing response on therapy with larotrectinib, suggesting efficacy of first-generation TRK inhibitors also in NTRK2-positive NSCLC

Robustness Certification for Point Cloud Models

The use of deep 3D point cloud models in safety-critical applications, such as autonomous driving, dictates the need to certify the robustness of these models to real-world transformations. This is technically challenging, as it requires a scalable verifier tailored to point cloud models that handles a wide range of semantic 3D transformations. In this work, we address this challenge and introduce 3DCertify, the first verifier able to certify the robustness of point cloud models. 3DCertify is based on two key insights: (i) a generic relaxation based on first-order Taylor approximations, applicable to any differentiable transformation, and (ii) a precise relaxation for global feature pooling, which is more complex than pointwise activations (e.g., ReLU or sigmoid) but commonly employed in point cloud models. We demonstrate the effectiveness of 3DCertify by performing an extensive evaluation on a wide range of 3D transformations (e.g., rotation, twisting) for both classification and part segmentation tasks. For example, we can certify robustness against rotations by $\pm$60{\deg} for 95.7% of point clouds, and our max pool relaxation increases certification by up to 15.6%.Comment: International Conference on Computer Vision (ICCV) 202

Prediction Along a Developmental Perspective in Psychiatry: How Far Might We Go?

Most mental disorders originate in childhood, and once symptoms present, a variety of psychosocial and cognitive maladjustments may arise. Although early childhood problems are generally associated with later mental health impairments and psychopathology, pluripotent transdiagnostic trajectories may manifest. Possible predictors range from behavioral and neurobiological mechanisms, genetic predispositions, environmental and social factors, and psychopathological comorbidity. They may manifest in altered neurodevelopmental trajectories and need to be validated capitalizing on large-scale multi-modal epidemiological longitudinal cohorts. Moreover, clinical and etiological variability between patients with the same disorders represents a major obstacle to develop effective treatments. Hence, in order to achieve stratification of patient samples opening the avenue of adapting and optimizing treatment for the individual, there is a need to integrate data from multi-dimensionally phenotyped clinical cohorts and cross-validate them with epidemiological cohort data. In the present review, we discuss these aspects in the context of externalizing and internalizing disorders summarizing the current state of knowledge, obstacles, and pitfalls. Although a large number of studies have already increased our understanding on neuropsychobiological mechanisms of mental disorders, it became also clear that this knowledge might only be the tip of the Eisberg and that a large proportion still remains unknown. We discuss prediction strategies and how the integration of different factors and methods may provide useful contributions to research and at the same time may inform prevention and intervention

Toward a general calibration of the Swiss plate geophone system for fractional bedload transport

Substantial uncertainties in bedload transport predictions in steep streams have encouraged intensive efforts towards the development of surrogate monitoring technologies. One such system, the Swiss plate geophone (SPG), has been deployed and calibrated in numerous steep channels, mainly in the Alps. Calibration relationships linking the signal recorded by the SPG system to the intensity and characteristics of transported bedload can vary substantially between different monitoring stations, likely due to site-specific factors such as flow velocity and bed roughness. Furthermore, recent flume experiments on the SPG system have shown that site-specific calibration relationships can be biased by elastic waves resulting from impacts occurring outside the plate boundaries. Motivated by these findings, we present a hybrid calibration procedure derived from flume experiments and an extensive dataset of 308 direct field measurements at four different SPG monitoring stations. Our main goal is to investigate the feasibility of a general, site-independent calibration procedure for inferring fractional bedload transport from the SPG signal. First, we use flume experiments to show that sediment size classes can be distinguished more accurately using a combination of vibrational frequency and amplitude information than by using amplitude information alone. Second, we apply this amplitude-frequency method to field measurements to derive general calibration coefficients for 10 different grain-size fractions. The amplitude-frequency method results in more homogeneous signal responses across all sites and significantly improves the accuracy of fractional sediment flux and grain-size estimates. We attribute the remaining site-to-site discrepancies to large differences in flow velocity and discuss further factors that may influence the accuracy of these bedload estimates.ISSN:2196-632XISSN:2196-631