Context
. The long-term ongoing HARPS radial velocity survey of extra-solar planets initiated in 2003 provides a unique data set with a 19-yr baseline that allows the detection of long-period ...exoplanets, brown dwarfs, and low-mass binaries.
Aims
. Our aim is to detect and characterise long-period companions around main sequence stars (spectral types late F to early M). Only 6% of the planets discovered so far have periods longer than 3 yr; we are probing this still largely unknown population.
Methods
. We use the radial velocity method to search for exoplanets around stars. The radial velocity variations are measured with HARPS at the ESO 3.6m telescope. Difficulties in characterising long-period exoplanets arise from the entanglement of the radial velocity with the stellar magnetic cycle. We thoroughly examined the stellar activity indicators to rule out magnetic cycles as the source of the observed variation. The true mass and inclination of our heavier companions are provided by astrometry, for which we use proper motions from H
IPPARCOS
and
Gaia.
Results
. Five Jupiter-mass exoplanets are reported to orbit HIP54597, BD-210397 (×2), HD 74698, and HD 94771 with 8.9 yr, 5.2 yr, 17.4 yr, 9.4 yr, and 5.9 yr orbits, and to have minimum masses of 2.01 ± 0.03, 0.7 ± 0.1, 2.4
−0.2
+1.5
, 0.40 ± 0.06, and 0.53 ± 0.03
M
J
respectively. HD 74698 also hosts a highly irradiated Neptune in a 15 day orbit with a minimum mass of 0.07 ± 0.01
M
J
. The mass and inclination of the exoplanets cannot yet be well constrained by astrometric measurements. Only HIP54597 b, HD 74698 c, and BD-210397 c have weak constraints. The mass of HIP54597 b can maximally increase by 10%–30%, the minimum mass of HD 74698 c is likely equal to its true mass, and BD-210397 c has a mass of 2.66
−0.32
+0.63
M
J
. HD 62364 hosts a brown dwarf with a true mass of 18.77
−0.63
+0.66
M
J
in an orbit of 14 yr. The mass of HD62364 b is around the limit of the masses of brown dwarfs, but its orbit is highly eccentric (
e
= 0.607 ± 0.005), which is more common among brown dwarfs than exoplanets. HD56380B, HD221638B, and HD 33473C have minimum masses within the brown dwarf limits, in orbits of 8.9 yr, 16.6 yr, and 50 yr respectively; however, astro-metric measurements reveal them to be stellar binaries, with masses of 375.3
−8.4
+8.6
, 110.0
−3.7
+3.9
, and 271.0
−3.8
+3.9
M
J
. The orbits of the stellar binaries HD 11938 and HD 61383 are incomplete. The preliminary result for HD 61383 is a 0.190
M
⊙
binary in a 39 yr orbit. The secondary of the binary system HD 11938 has a mass of 0.33
M
⊙
, which is confirmed by a secondary peak in the cross-correlation function, and a preliminary period of 35 yr. The origin of the 3.0 yr radial velocity signal of HD 3964 is uncertain as it shows entanglement with the magnetic cycle of the star. We finally report one more star, HD 11608, with a magnetic cycle that mimics a planetary signal.
Conclusions
. We present the discovery of six exoplanets, one uncertain exoplanet candidate, one brown dwarf, and five stellar binaries around main sequence stars. We also improve the orbital solution of the stellar binary HD 33473C thanks to long-term monitoring.
B cell superantigens crosslink conserved domains of B cell receptors (BCRs) and cause dysregulated, polyclonal B cell activation irrespective of normal BCR-antigen complementarity. The cells ...typically succumb to activation-induced cell death, which can impede the adaptive immune response and favor infection. In the present study, we demonstrate that the fucose-binding lectin of
Burkholderia ambifaria
, BambL, bears functional resemblance to B cell superantigens. By engaging surface glycans, the bacterial lectin activated human peripheral blood B cells, which manifested in the surface expression of CD69, CD54 and CD86 but became increasingly cytotoxic at higher concentrations. The effects were sensitive to BCR pathway inhibitors and excess fucose, which corroborates a glycan-driven mode of action. Interactome analyses in a model cell line suggest BambL binds directly to glycans of the BCR and regulatory coreceptors. In vitro, BambL triggered BCR signaling and induced CD19 internalization and degradation. Owing to the lectin’s six binding sites, we propose a BCR activation model in which BambL functions as a clustering hub for receptor glycans, modulates normal BCR regulation, and induces cell death through exhaustive activation.
Our aim is to detect and characterise long-period companions around main sequence stars (spectral types late F to early M). We use the RV method to search for exoplanets around stars. The RV ...variations are measured with HARPS at the ESO 3.6 metre telescope. The true mass and inclination of our heavier companions are provided by astrometry, for which we use proper motions from Hipparcos and Gaia. Five Jupiter-mass exoplanets are reported to orbit HIP54597, BD-210397 (x2), HD74698, and HD94771 with 8.9 yr, 5.2 yr, 17.4 yr, 9.4 yr, and 5.9 yr orbits, and to have minimum masses of \(2.01 \pm 0.03\), \(0.7 \pm 0.1\), \(2.4^{+1.5}_{-0.2}\), \(0.40 \pm 0.06\), and \(0.53 \pm 0.03 M_J\) respectively. HD74698 also hosts a highly irradiated Neptune in a 15 day orbit with a minimum mass of \(0.07 \pm 0.01 M_J\). The mass of HIP54597 b can maximally increase by 10% - 30%, the minimum mass of HD74698 c is likely equal to its true mass, and BD-210397 c has a mass of \(2.66^{+0.63}_{-0.32} M_J\). HD62364 hosts a brown dwarf with a true mass of \(18.77^{+0.66}_{-0.63} M_J\) in an orbit of 14 yr. HD56380B, HD221638B, and HD33473C have minimum masses within the brown dwarf limits, in orbits of 8.9 yr, 16.6 yr, and 50 yr respectively; however, astrometric measurements reveal them to be stellar binaries, with masses of \(375.3^{+8.6}_{-8.4}\), \(110.0^{+3.9}_{-3.7}\), and \(271.0^{+3.9}_{-3.8} M_J\). The orbits of the stellar binaries HD11938 and HD61383 are incomplete. The preliminary result for HD61383 is a 0.190 \(M_{\odot}\) binary in a 39 yr orbit. The secondary of the binary system HD11938 has a mass of 0.33 \(M_{\odot}\) - which is confirmed by a secondary peak in the CCF - and a preliminary period of 35 yr. The origin of the 3.0 yr RV signal of HD3964 is uncertain as it shows entanglement with the magnetic cycle of the star. We finally report one more star, HD11608, with a magnetic cycle that mimics a planetary signal.
Hot Jupiters generally do not have nearby planet companions, as they may have cleared out other planets during their inward migration from more distant orbits. This gives evidence that hot Jupiters ...more often migrate inward via high-eccentricity migration due to dynamical interactions between planets rather than more dynamically cool migration mechanisms through the protoplanetary disk. Here we further refine the unique system of WASP-132 by characterizing the mass of the recently validated 1.0-day period super-Earth WASP-132c (TOI-822.02) interior to the 7.1-day period hot Jupiter WASP-132b. Additionally, we announce the discovery of a giant planet at a 5-year period (2.7 AU). We also detect a long-term trend in the radial velocity data indicative of another outer companion. Using over nine years of CORALIE RVs and over two months of highly-sampled HARPS RVs, we determine the masses of the planets from smallest to largest orbital period to be M\(_{\rm{c}}\) = \(6.26^{+1.84}_{-1.83}\) \(M_{\oplus}\), M\(_{\rm{b}}\) = \(0.428^{+0.015}_{-0.015}\) \(M_{\rm{Jup}}\), and M\(_{\rm{d}}\sin{i}\) = \(5.16^{+0.52}_{-0.52}\) \(M_{\rm{Jup}}\), respectively. Using TESS and CHEOPS photometry data we measure the radii of the two inner transiting planets to be \(1.841^{+0.094}_{-0.093}\) \(R_{\oplus}\) and \(0.901^{+0.038}_{-0.038}\) \(R_{\rm{Jup}}\). WASP-132 is a unique multi-planetary system in that both an inner rocky planet and an outer giant planet are in a system with a hot Jupiter. This suggests it migrated via a more rare dynamically cool mechanism and helps to further our understanding of how hot Jupiter systems may form and evolve.
Several major theories of skill acquisition assume that with continued practice on a serial task component processes are merged together into larger knowledge structures. Two experiments tested ...alternative hypotheses regarding the transfer of knowledge following extended practice on a serial task by determining whether component knowledge or merged knowledge is transferred between two tasks. Results from Experiment 1 were shown to be consistent with the assumption that merged knowledge can be transferred to a novel task. Results from Experiment 2 showed that, after extended practice on the original task, the amount of merged knowledge shared by the original and transfer tasks was a better predictor of performance on the transfer task than was the amount of shared component knowledge. These findings extend current theories of skill transfer and provide important constraints for theories of skill acquisition.
Attention and Implicit Learning provides a comprehensive overview of the research conducted in this area. The book is conceived as a multidisciplinary forum of discussion on the question of whether ...implicit learning may be depicted as a process that runs independently of attention. The volume also deals with the complementary question of whether implicit learning affects the dynamics of attention, and it addresses these questions from perspectives that range from functional to neuroscientific and computational approaches. The view of implicit learning that arises from these pages is not that of a mysterious faculty, but rather that of an elementary ability of the cognitive systems to extract the structure of their environment as it appears directly through experience, and regardless of any intention to do so. Implicit learning, thus, is taken to be a process that may shape not only our behavior, but also our representations of the world, our attentional functions, and even our conscious experience. (Series B).
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