| 1. |
- Weiner, D. J., et al.
(författare)
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Polygenic transmission disequilibrium confirms that common and rare variation act additively to create risk for autism spectrum disorders
- 2017
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 49:7, s. 978-
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Tidskriftsartikel (refereegranskat)abstract
- Autism spectrum disorder (ASD) risk is influenced by common polygenic and de novo variation. We aimed to clarify the influence of polygenic risk for ASD and to identify subgroups of ASD cases, including those with strongly acting de novo variants, in which polygenic risk is relevant. Using a novel approach called the polygenic transmission disequilibrium test and data from 6,454 families with a child with ASD, we show that polygenic risk for ASD, schizophrenia, and greater educational attainment is over-transmitted to children with ASD. These findings hold independent of proband IQ. We find that polygenic variation contributes additively to risk in ASD cases who carry a strongly acting de novo variant. Lastly, we show that elements of polygenic risk are independent and differ in their relationship with phenotype. These results confirm that the genetic influences on ASD are additive and suggest that they create risk through at least partially distinct etiologic pathways.
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| 2. |
- Anney, R. J. L., et al.
(författare)
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Meta-analysis of GWAS of over 16,000 individuals with autism spectrum disorder highlights a novel locus at 10q24.32 and a significant overlap with schizophrenia
- 2017
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Ingår i: Molecular Autism. - : Springer Science and Business Media LLC. - 2040-2392. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Background: Over the past decade genome-wide association studies (GWAS) have been applied to aid in the understanding of the biology of traits. The success of this approach is governed by the underlying effect sizes carried by the true risk variants and the corresponding statistical power to observe such effects given the study design and sample size under investigation. Previous ASD GWAS have identified genome-wide significant (GWS) risk loci; however, these studies were of only of low statistical power to identify GWS loci at the lower effect sizes (odds ratio (OR) < 1.15). Methods: We conducted a large-scale coordinated international collaboration to combine independent genotyping data to improve the statistical power and aid in robust discovery of GWS loci. This study uses genome-wide genotyping data from a discovery sample (7387 ASD cases and 8567 controls) followed by meta-analysis of summary statistics from two replication sets (7783 ASD cases and 11359 controls; and 1369 ASD cases and 137308 controls). Results: We observe a GWS locus at 10q24.32 that overlaps several genes including PITX3, which encodes a transcription factor identified as playing a role in neuronal differentiation and CUEDC2 previously reported to be associated with social skills in an independent population cohort. We also observe overlap with regions previously implicated in schizophrenia which was further supported by a strong genetic correlation between these disorders (Rg = 0.23; P= 9 x10(-6)). We further combined these Psychiatric Genomics Consortium (PGC) ASD GWAS data with the recent PGC schizophrenia GWAS to identify additional regions which may be important in a common neurodevelopmental phenotype and identified 12 novel GWS loci. These include loci previously implicated in ASD such as FOXP1 at 3p13, ATP2B2 at 3p25.3, and a 'neurodevelopmental hub' on chromosome 8p11.23. Conclusions: This study is an important step in the ongoing endeavour to identify the loci which underpin the common variant signal in ASD. In addition to novel GWS loci, we have identified a significant genetic correlation with schizophrenia and association of ASD with several neurodevelopmental- related genes such as EXT1, ASTN2, MACROD2, and HDAC4.
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| 3. |
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| 4. |
- Danilovich, T., et al.
(författare)
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ATOMIUM: halide molecules around the S-type AGB star W Aquilae
- 2021
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 655
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Tidskriftsartikel (refereegranskat)abstract
- Context. S-type asymptotic giant branch (AGB) stars are thought to be intermediates in the evolution of oxygen- to carbon-rich AGB stars. The chemical compositions of their circumstellar envelopes are also intermediate but have not been studied in as much detail as their carbon- and oxygen-rich counterparts. W Aql is a nearby S-type star, with well-known circumstellar parameters, making it an ideal object for in-depth study of less common molecules. Aims. We aim to determine the abundances of AlCl and AlF from rotational lines, which have been observed for the first time towards an S-type AGB star. In combination with models based on PACS observations, we aim to update our chemical kinetics network based on these results. Methods. We analyse ALMA observations towards W Aql of AlCl in the ground and first two vibrationally excited states and AlF in the ground vibrational state. Using radiative transfer models, we determine the abundances and spatial abundance distributions of (AlCl)-Cl-35, (AlCl)-Cl-37, and AlF. We also model HCl and HF emission and compare these models to PACS spectra to constrain the abundances of these species. Results. AlCl is found in clumps very close to the star, with emission confined within 0 ''.1 of the star. AlF emission is more extended, with faint emission extending 0 ''.2 to 0 ''.6 from the continuum peak. We find peak abundances, relative to H-2, of 1.7 x 10(-7) for (AlCl)-Cl-35, 7 x 10(-8) for (AlCl)-Cl-37, and 1 x 10(-7) for AlF. From the PACS spectra, we find abundances of 9.7 x 10(-8) and <= 10(-8), relative to H-2, for HCl and HF, respectively. Conclusions. The AlF abundance exceeds the solar F abundance, indicating that fluorine synthesised in the AGB star has already been dredged up to the surface of the star and ejected into the circumstellar envelope. From our analysis of chemical reactions in the wind, we conclude that AlF may participate in the dust formation process, but we cannot fully explain the rapid depletion of AlCl seen in the wind.
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| 5. |
- Danilovich, Taissa, 1987, et al.
(författare)
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Chemical tracers of a highly eccentric AGB–main-sequence star binary
- 2024
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Ingår i: Nature Astronomy. - 2397-3366.
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Tidskriftsartikel (refereegranskat)abstract
- Binary interactions have been proposed to explain a variety of circumstellar structures seen around evolved stars, including asymptotic giant branch (AGB) stars and planetary nebulae. Studies resolving the circumstellar envelopes of AGB stars have revealed spirals, disks and bipolar outflows, with shaping attributed to interactions with a companion. Here we use a combined chemical and dynamical analysis to reveal a highly eccentric and long-period orbit for W Aquilae, a binary system containing an AGB star and a main-sequence companion. Our results are based on anisotropic SiN emission, the detections of irregular NS and SiC emission towards the S-type star, and density structures observed in the CO emission. These features are all interpreted as having formed during periastron interactions. Our astrochemistry-based method can yield stringent constraints on the orbital parameters of long-period binaries containing AGB stars, and will be applicable to other systems.
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| 8. |
- Wallström, Sofia, 1988, et al.
(författare)
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ATOMIUM: Molecular inventory of 17 oxygen-rich evolved stars observed with ALMA
- 2024
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 681
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Tidskriftsartikel (refereegranskat)abstract
- Context. The dusty winds of cool evolved stars are a major contributor of the newly synthesised material enriching the Galaxy and future generations of stars. However, the details of the physics and chemistry behind dust formation and wind launching have yet to be pinpointed. Recent spatially resolved observations show the importance of gaining a more comprehensive view of the circumstellar chemistry, but a comparative study of the intricate interplay between chemistry and physics is still difficult because observational details such as frequencies and angular resolutions are rarely comparable. Aims. Aiming to overcome these deficiencies, ATOMIUM is an ALMA Large Programme to study the physics and chemistry of the circumstellar envelopes of a diverse set of oxygen-rich evolved stars under homogeneous observing conditions at three angular resolutions between ∼0.02′1.4′. Here we summarize the molecular inventory of these sources, and the correlations between stellar parameters and molecular content. Methods. Seventeen oxygen-rich or S-Type asymptotic giant branch (AGB) and red supergiant (RSG) stars have been observed in several tunings with ALMA Band 6, targeting a range of molecules to probe the circumstellar envelope and especially the chemistry of dust formation close to the star. We systematically assigned the molecular carriers of the spectral lines and measured their spectroscopic parameters and the angular extent of the emission of each line from integrated intensity maps. Results. Across the ATOMIUM sample, we detect 291 transitions of 24 different molecules and their isotopologues. This includes several first detections in oxygen-rich AGB/RSG stars: PO v = 1, SO2 v1 = 1 and v2 = 2, and several high energy H2O transitions. We also find several first detections in S-Type AGB stars: vibrationally excited HCN v2 = 2,3 and SiS v = 4,5,6, as well as first detections of the molecules SiC, AlCl, and AlF in W Aql. Overall, we find strong correlations between the following molecular pairs: CS and SiS, CS and AlF, NaCl and KCl, AlO and SO, SO2 and SO, and SO2 and H2O; meaning both molecules tend to have more detected emission lines in the same sources. The measured isotopic ratios of Si and S are found to be consistent with previous measurements, except for an anomalously high 29Si/30Si ratio of 4 ± 1 in the RSG VX Sgr. Conclusions. This paper presents the overall molecular inventory and an initial analysis of the large ATOMIUM dataset, laying the groundwork for future work deriving molecular abundances and abundance profiles using radiative transfer modeling which will provide more rigorous tests for chemical models.
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| 9. |
- Decin, L., et al.
(författare)
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(Sub)stellar companions shape the winds of evolved stars
- 2020
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 369:6509, s. 1497-1500
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Tidskriftsartikel (refereegranskat)abstract
- Binary interactions dominate the evolution of massive stars, but their role is less clear for low- and intermediate-mass stars. The evolution of a spherical wind from an asymptotic giant branch (AGB) star into a nonspherical planetary nebula (PN) could be due to binary interactions. We observed a sample of AGB stars with the Atacama Large Millimeter/submillimeter Array (ALMA) and found that their winds exhibit distinct nonspherical geometries with morphological similarities to planetary nebulae (PNe). We infer that the same physics shapes both AGB winds and PNe; additionally, the morphology and AGB mass-loss rate are correlated. These characteristics can be explained by binary interaction. We propose an evolutionary scenario for AGB morphologies that is consistent with observed phenomena in AGB stars and PNe.
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| 10. |
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