The SOPHIE search for northern extrasolar planets XIV. A temperate (Teq ~ 300 K) super-earth around the nearby star Gliese 411

Periodic radial velocity variations in the nearby M-dwarf star Gl 411 are reported, based on measurements with the SOPHIE spectrograph. Current data do not allow us to distinguish between a 12.95-day period and its one-day alias at 1.08 days, but favour the former slightly. The velocity variation has an amplitude of 1.6 m s−1, making this the lowest-amplitude signal detected with SOPHIE up to now. We have performed a detailed analysis of the significance of the signal and its origin, including extensive simulations with both uncorrelated and correlated noise, representing the signal induced by stellar activity. The signal is significantly detected, and the results from all tests point to its planetary origin. Additionally, the presence of an additional acceleration in the velocity time series is suggested by the current data. On the other hand, a previously reported signal with a period of 9.9 days, detected in HIRES velocities of this star, is not recovered in the SOPHIE data. An independent analysis of the HIRES dataset also fails to unveil the 9.9-day signal. If the 12.95-day period is the real one, the amplitude of the signal detected with SOPHIE implies the presence of a planet, called Gl 411 b, with a minimum mass of around three Earth masses, orbiting its star at a distance of 0.079 AU. The planet receives about 3.5 times the insolation received by Earth, which implies an equilibrium temperature between 256 and 350 K, and makes it too hot to be in the habitable zone. At a distance of only 2.5 pc, Gl 411 b, is the third closest low-mass planet detected to date. Its proximity to Earth will permit probing its atmosphere with a combination of high-contrast imaging and high-dispersion spectroscopy in the next decade

Incrementally semi-supervised classification of arthritis inflammation on a clinical dataset

For best medical imaging application results, learning-based approaches such as deep learning necessitate specific, extensive and precise annotations. Outside well-curated public benchmarks, these are rarely available in practice, and so it becomes necessary to use less-than-perfect annotations. One way of compensating for this is the embedding of anatomical knowledge. Complementing this, there is the incremental semi-supervised learning technique, whereby a small amount of annotations can be used to derive more and superior labels. In this article, we illustrate this approach on a deep learning system to help radiologists and rheumatologists finely and interactively assess MRI scans of the sacro-iliac joint in order to correctly diagnose Axial Spondyloarthritis. Our model is trained initially on a relatively small set of images with promising results, on par with expert opinion and generalizable to new datasets

Incrementally semi-supervised classification of arthritis inflammation on a clinical dataset

International audienceFor best medical imaging application results, learning-based approaches such as deep learning necessitate specific, extensive and precise annotations. Outside well-curated public benchmarks, these are rarely available in practice, and so it becomes necessary to use less-than-perfect annotations. One way of compensating for this is the embedding of anatomical knowledge. Complementing this, there is the incremental semi-supervised learning technique, whereby a small amount of annotations can be used to derive more and superior labels.In this article, we illustrate this approach on a deep learning system to help radiologists and rheumatologists finely and interactively assess MRI scans of the sacro-iliac joint in order to correctly diagnose Axial Spondyloarthritis. Our model is trained initially on a relatively small set of images with promising results, on par with expert opinion and generalizable to new datasets

A Role for Taok2 in Listeria monocytogenes Vacuolar Escape

International audienceThe bacterial pathogen Listeria monocytogenes invades host cells, ruptures the internalization vacuole, and reaches the cytosol for replication. A high-content small interfering RNA (siRNA) microscopy screen allowed us to identify epithelial cell factors involved in L. monocytogenes vacuolar rupture, including the serine/threonine kinase Taok2. Kinase activity inhibition using a specific drug validated a role for Taok2 in favoring L. monocytogenes cytoplasmic access. Furthermore, we showed that Taok2 recruitment to L. monocytogenes vacuoles requires the presence of pore-forming toxin listeriolysin O. Overall, our study identified the first set of host factors modulating L. monocytogenes vacuolar rupture and cytoplasmic access in epithelial cells

The SOPHIE search for northern extrasolar planets XVI. HD 158259: A compact planetary system in a near-3:2 mean motion resonance chain

Aims. Since 2011, the SOPHIE spectrograph has been used to search for Neptunes and super-Earths in the northern hemisphere. As part of this observational program, 290 radial velocity measurements of the 6.4 V magnitude star HD 158259 were obtained. Additionally, TESS photometric measurements of this target are available. We present an analysis of the SOPHIE data and compare our results with the output of the TESS pipeline. Methods. The radial velocity data, ancillary spectroscopic indices, and ground-based photometric measurements were analyzed with classical and ℓ1 periodograms. The stellar activity was modeled as a correlated Gaussian noise and its impact on the planet detection was measured with a new technique. Results. The SOPHIE data support the detection of five planets, each with m sin i ≈ 6 M⊕, orbiting HD 158259 in 3.4, 5.2, 7.9, 12, and 17.4 days. Though a planetary origin is strongly favored, the 17.4 d signal is classified as a planet candidate due to a slightly lower statistical significance and to its proximity to the expected stellar rotation period. The data also present low frequency variations, most likely originating from a magnetic cycle and instrument systematics. Furthermore, the TESS pipeline reports a significant signal at 2.17 days corresponding to a planet of radius ≈1.2 R⊕. A compatible signal is seen in the radial velocities, which confirms the detection of an additional planet and yields a ≈2 M⊕ mass estimate. Conclusions. We find a system of five planets and a strong candidate near a 3:2 mean motion resonance chain orbiting HD 158259. The planets are found to be outside of the two and three body resonances