67 research outputs found
Recurring adaptive introgression of a supergene variant that determines social organization
Introgression has been proposed as an essential source of adaptive genetic variation. However, a key barrier to adaptive introgression is that recombination can break down combinations of alleles that underpin many traits. This barrier might be overcome in supergene regions, where suppressed recombination leads to joint inheritance across many loci. Here, we study the evolution of a large supergene region that determines a major social and ecological trait in Solenopsis fire ants: whether colonies have one queen or multiple queens. Using coalescent-based phylogenies built from the genomes of 365 haploid fire ant males, we show that the supergene variant responsible for multiple-queen colonies evolved in one species and repeatedly spread to other species through introgressive hybridization. This finding highlights how supergene architecture can enable a complex adaptive phenotype to recurrently permeate species boundaries
Degenerative expansion of a young supergene.
Long term suppression of recombination ultimately leads to gene loss, as demonstrated by the depauperate Y and W chromosomes of long-established pairs of XY and ZW chromosomes. The young social supergene of the Solenopsis invicta red fire ant provides a powerful system to examine the effects of suppressed recombination over a shorter timescale. The two variants of this supergene are carried by a pair of heteromorphic chromosomes, referred to as the social B and social b (SB and Sb) chromosomes. The Sb variant of this supergene changes colony social organization and has an inheritance pattern similar to a Y or W chromosome because it is unable to recombine. We used high-resolution optical mapping, k-mer distribution analysis and quantification of repetitive elements on haploid ants carrying alternate variants of this young supergene region. We find that instead of shrinking, the Sb variant of the supergene has increased in length by more than 30%. Surprisingly, only a portion of this length increase is due to consistent increases in the frequency of particular classes of repetitive elements. Instead, haplotypes of this supergene variant differ dramatically in the amounts of other repetitive elements, indicating that the accumulation of repetitive elements is a heterogeneous and dynamic process. This is the first comprehensive demonstration of degenerative expansion in an animal and shows that it occurs through non-linear processes during the early evolution of a region of suppressed recombination
How a slow-ovipositing parasitoid can succed as a biological control agent of the invasive mealybug Phenacoccus peruvianus: implications for future classical and conservation biological control programs
[EN] Phenaccocus peruvianus Granara de Willink (Hemiptera: pseudococcidae) is an invasive mealybug that has become a pest of ornamental plants in Europe and has recently been detected in California, USA. In this work, we studied the tritrophic interaction among this mealybug, its main parasitoid Acerophagus n. sp. near coccois (Hymenoptera: Encyrtidae) and tending ants to disclose the success of this parasitoid controlling P. peruvianus. Acerophagus n. sp. near coccois accepted mealybugs for parasitism regardless of their size but did not hostfeed. We recorded three active defenses of P. peruvianus. Host handling time-consuming process that required more than 30 min. Tending ants, Lasius grandis (Hymenoptera: Encyrtidae), reduced the time spent by parasitoids in a patch and disrupted oviposition attempts. The low numbers of ants tending mealybugs colonies in Spain and France could explain why this parasitoid, with a long handling time, is an efficient biological control agent for P. peruvianus.Beltrà Ivars, A.; Soto Sánchez, AI.; Tena Barreda, A. (2015). How a slow-ovipositing parasitoid can succed as a biological control agent of the invasive mealybug Phenacoccus peruvianus: implications for future classical and conservation biological control programs. BioControl. 60(4):473-484. https://doi.org/10.1007/s10526-015-9663-6S473484604Arakelian G (2013) Bougainvillea mealybug (Phenacoccus peruvianus). Factsheet 2013. County of Los Angeles. Department of agricultural commissioner/weights and measures, USABartlett BR (1961) The influence of ants upon parasites, predators, and scale insects. Ann Entomol Soc Am 54:543–551Bartlett BR (1978) Pseudococcidae. In: Clausen CP (ed) Introduced parasites and predators of arthropod pests and weeds: a world review, 1st edn. Agricultural Research Service USDA, Washington, USA, pp 137–170Barzman MS, Daane KM (2001) Host-handling behaviors in parasitoids of black scale, Saissetia oleae (Homoptera: Coccidae): a case for ant-mediated evolution. J Anim Ecol 70:237–247Beltrà A, Soto A, Germain JF, Matile-Ferrero D, Mazzeo G, Pellizzari G, Russo A, Franco JC, Williams DJ (2010) The Bougainvillea mealybug Phenacoccus peruvianus, a rapid invader from South America to Europe. Entomol Hell 19:137–143Beltrà A, Garcia-Marí F, Soto A (2013a) Seasonal phenology, spatial distribution, and sampling plan for the invasive mealybug Phenacoccus peruvianus (Hemiptera: Pseudococcidae). J Econ Entomol 106:1486–1494Beltrà A, Tena A, Soto A (2013b) Fortuitous biological control of the invasive mealybug Phenacoccus peruvianus in Southern Europe. BioControl 58:309–317Beltrà A, Tena A, Soto A (2013c) Reproductive strategies and food sources used by Acerophagus n. sp. near coccois, a new successful parasitoid of the invasive mealybug Phenacoccus peruvianus. J Pest Sci 86:253–259Berlinger MJ, Golberg AM (1978) The effect of the fruit sepals on the citrus mealybug population and on its parasite. Entomol Exp Appl 24:238–243Blumstein DT, Daniel JC (2007) Quantifying behavior the JWatcher way. Sinauer Associates Inc., Sunderland, UKBoavida C, Ahounou M, Vos M, Neuenschwander P, van Alphen JJM (1995) Host stage selection and sex allocation by Gyranusoidea tebygi (Hymenoptera: Encyrtidae), a parasitoid of the mango mealybug, Rastrococcus invadens (Homoptera: Pseudococcidae). Biol Control 5:487–496Bokonon-Ganta AH, Neuenschwander P, van Alphen JJM, Vos M (1995) Host stage selection and sex allocation by Anagyrus mangicola (Hymenoptera: Encyrtidae), a parasitoid of the mango mealybug, Rastrococcus invadens (Homoptera: Pseudococcidae). Biol Control 5:479–486Bugila AAA, Franco JC, Borges da Silva E, Branco M (2014a) Defense response of native and alien mealybugs (Hemiptera: Pseudococcidae) against the solitary parasitoid Anagyrus sp. nr. pseudococci (Girault) (Hymenoptera: Encyrtidae). J Insect Behav 27:439–453Bugila AAA, Branco M, Borges da Silva E, Franco JC (2014b) Host selection behavior and specificity of the solitary parasitoid of mealybugs Anagyrus sp. nr. pseudococci (Girault) (Hymenoptera, Encyrtidae). Biocontrol Sci Techn 24:22–38Bynum EK (1937) Pseudococcobius terryi Fullaway, a Hawaiian parasite of Gray Sugarcane mealybug in the United States. J Econ Entomol 30:756–761Cadée N, van Alphen JJM (1997) Host selection and sex allocation in Leptomastidea abnormis, a parasitoid of the citrus mealybug Planococcus citri. Entomol Exp Appl 83:277–284Clausen CP (1924) The parasites of Pseudococcus maritimus (Ehrhorn) in California (Hymenoptera, Chalcidoidea). Part II. Biological studies and life histories. UC Pub Entomol 3:253–288Daane KM, Barzman MS, Caltagirone LE, Hagen KS (2000) Metaphycus anneckei and Metaphycus hageni: two discrete species parasitic on black scale, Saissetia oleae. BioControl 45:269–284Daane KM, Bentley WJ, Walton VM, Malakar-Kuenen R, Millar JC, Ingels CA, Weber EA, Gispert C (2006) New controls investigated for vine mealybug. Calif Agric 60:31–38Daane KM, Sime KR, Fallon J, Cooper ML (2007) Impacts of Argentine ants on mealybugs and their natural enemies in California’s coastal vineyards. Ecol Entomol 32:583–596De Farias AM, Hopper KR (1999) Oviposition behavior of Aphelinus asychis (Hymenoptera: Aphelinidae) and Aphidius matricariae (Hymenoptera: Aphidiidae) and defense behavior of their host Diuraphis noxia (Homoptera: Aphididae). Environ Entomol 28:858–862Dorn B, Mattiacci L, Bellotti AC, Dorn S (2001) Host specificity and comparative foraging behavior of Aenasius vexans and Acerophagus coccois, two endo-parasitoids of the cassava mealybug. Entomol Exp Appl 99:331–339Eisner T, Silberglied RE (1988) A chrysopid larva that cloaks itself in mealybug wax. Psyche 95:15–20Flanders SE (1963) Predation by parasitic Hymenoptera, the basis of ant-induced outbreaks of a host species. J Econ Entomol 56:116Foldi I (1983) Structure et fonctions des glandes tégumentaires de cochenilles Pseudococcines et de leurs secretions. Ann Soc Entomol Fr 19:155–156Foldi I (1997) Defense strategies in scale insects: phylogenetic inference and evolutionary scenarios (Hemiptera, Coccoidea). In: Grandcolas P (ed) The origin of biodiversity in insects: phylogenetic tests of evolutionary scenarios, 1st edn. Muséum National d’Histoire Naturelle, Paris, France, pp 203–230Godfray HCJ (1994) Parasitoids: behavioral and evolutionary ecology. Princeton University Press, Princeton, USAGonzález-Hernández H, Johnson MW, Reimer NJ (1999) Impact of Pheidole megacephala (F.) (Hymenoptera: Formicidae) on the biological control of Dysmicoccus brevipes (Cockerell) (Homoptera: Pseudococcidae). Biol Control 15:145–152Gross P (1993) Insect behavioral and morphological defenses against parasitoids. Annu Rev Entomol 38:251–273Gullan PJ (1997) Relationships with ants. In: Ben-Dov Y, Hodgson CJ (eds) Soft scale insects—their biology natural enemies and control, 1st edn. Elsevier, Amsterdam, The Netherlands, pp 351–373Gullan PJ, Kosztarab M (1997) Adaptations in scale insects. Annu Rev Entomol 42:23–50Hcidari M, Jahan M (2000) A study of ovipositional behavior of Anagyrus pseudococci a parasitoid of mealybugs. J Agric Sci Technol 2:49–53Honda JY, Luck RF (1995) Scale morphology effects on feeding behavior and biological control potential of Rhyzobius lophanthae (Coleoptera: Coccinellidae). Ann Entomol Soc Am 88:441–450Joyce AL, Hoddle MS, Bellows TS, Gonzalez D (2001) Oviposition behavior of Coccidoxenoides peregrinus, a parasitoid of Planococcus ficus. Entomol Exp Appl 98:49–57Karamaouna F (1999) Biology of the parasitoids Leptomastix epona (Walker) and Pseudaphycus flavidulus (Brèthes) and behavioural interactions with the host mealybug Pseudococcus viburni (Signoret). Ph.D. Thesis, University of London, UK, p 333Karamaouna F, Copland MJ (2000) Oviposition behavior, influence of experience on host size selection, and niche overlap of the solitary Leptomastix epona and the gregarious Pseudaphycus flavidulus, two endoparasitoids of the mealybug Pseudococcus viburni. Entomol Exp Appl 97:301–308Klotz JH, Hansen L, Pospischil R, Rust M (2008) Urban ants of North America and Europe. Cornell University Press, Ithaca, USAMailleux AC, Deneubourg JL, Detrain C (2003) Regulation of ants foraging to resource productivity. P R Soc Lond B Bio 270:1609–1616Majerus ME, Sloggett JJ, Godeau JF, Hemptinne JL (2007) Interactions between ants and aphidophagous and coccidophagous ladybirds. Popul Ecol 49:15–27Mgocheki N, Addison P (2009) Interference of ants (Hymenoptera: Formicidae) with biological control of the vine mealybug Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae). Biol Control 49:180–185Moore D (1988) Agents used for biological control of mealybugs (Pseudococcidae). Biocontrol News Inf 9:209–225Paris CI, Espadaler X (2009) Honeydew collection by the invasive garden ant Lasius neglectus versus the native ant L grandis. Arthropod Plant Interact 3:75–85Pekas A, Tena A, Aguilar A, Garcia-Marí F (2011) Spatio-temporal patterns and interactions with honeydew-producing Hemiptera of ants in a Mediterranean citrus orchard. Agric Forest Entomol 13:89–97Pennacchio F, Strand MR (2006) Evolution of developmental strategies in parasitic Hymenoptera. Annu Rev Entomol 51:233–258Pijls JW, Hofker KD, Staalduinen MJ, van Alphen JJM (1995) Interspecific host discrimination and competition in Apoanagyrus (Epidinocarsis) lopezi and A(E) diversicornis parasitoids of the cassava mealybug Phenacoccus manihoti. Ecol Entomol 20:326–332Robert Y (1987) Dispersion and migration. In: Minks AK, Harrewijn P (eds) Aphids—their biology, natural enemies and control, 1st edn. Elsevier, Amsterdam, The Netherlands, pp 299–313Sandanayaka WRM, Charles JG, Allan DJ (2009) Aspects of the reproductive biology of Pseudaphycus maculipennis (Hym: Encyrtidae), a parasitoid of obscure mealybug, Pseudococcus viburni (Hem: Pseudococcidae). Biol Control 48:30–35Sarkar D (2008) Lattice: multivariate data visualization with R. Springer, New York, USASime KR, Daane KM (2014) Rapid, non-discriminatory oviposition behaviors are favored in mealybug parasitoids when Argentine ants are present. Environ Entomol 43:995–1002Tena A, Garcia-Marí F (2008) Suitability of citricola scale Coccus pseudomagnoliarum (Hemiptera: Coccidae) as host of Metaphycus helvolus (Hymenoptera: Encyrtidae): Influence of host size and encapsulation. Biol Control 46:341–347Tena A, Hoddle CD, Hoddle MS (2013) Competition between honeydew producers in an ant–hemipteran interaction may enhance biological control of an invasive pest. Bull Entomol Res 103:714–723The R Core Team (2011) R: a language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austriavan Driesche RG, Belloti A, Herrera CJ, Castello JA (1987a) Host preferences of two encyrtid parasitoids for the Columbian Phenacoccus spp. of cassava mealybugs. Entomol Exp Appl 43:261–266van Driesche RG, Belloti A, Herrera CJ, Castello JA (1987b) Host feeding and ovipositor insertion as sources of mortality in the mealybug Phenacoccus herreni caused by two encyrtids Epidinocarsis diversicornis and Acerophagus coccois. Entomol Exp Appl 44:97–100Vet LE, Dicke M (1992) Ecology of infochemical use by natural enemies in a tritrophic context. Annu Rev Entomol 37:141–172Völkl W, Woodring J, Fischer M, Lorenz MW, Hoffmann KH (1999) Ant-aphid mutualisms: the impact of honeydew production and honeydew sugar composition on ant preferences. Oecologia 118:483–491Wajnberg E (1989) Analysis of variations of handling-time in Trichogramma maidis. Entomophaga 34:397–407Way MJ (1963) Mutualism between ants and honeydew-producing Homoptera. Annu Rev Entomol 8:307–344Weiss MR (2006) Defecation behavior and ecology of insects. Annu Rev Entomol 51:635–661Wyckhuys KAG, Stone L, Desneux N, Hoelmer KA, Hopper KR, Heimpel GE (2008) Parasitism of the soybean aphid Aphis glycines by Binodoxys communis: the role of aphid defensive behavior and parasitoid reproductive performance. Bull Entomol Res 98:361–370Zain-ul-Abdin, Arif MJ, Suhail A, Gogi MD, Arshad M, Wakil W, Abbas SK, Altaf A, Shaina H, Manzoor A (2012) Molecular analysis of the venom of mealybug parasitoid Aenasius bambawalei Hayat (Hymenoptera: Encyrtidae). Pak Entomol 34:189–193Zinna G (1959) Specializzazione entomoparassitica negli Encyrtidae: studio morfologico etologico e fisiologico del Leptomastix dactylopii. Howard Boll Lab agr Filippo Silvestri 18:1–14
What Do We Know About Neuropsychological Aspects Of Schizophrenia?
Application of a neuropsychological perspective to the study of schizophrenia has established a number of important facts about this disorder. Some of the key findings from the existing literature are that, while neurocognitive impairment is present in most, if not all, persons with schizophrenia, there is both substantial interpatient heterogeneity and remarkable within-patient stability of cognitive function over the long-term course of the illness. Such findings have contributed to the firm establishment of neurobiologic models of schizophrenia, and thereby help to reduce the social stigma that was sometimes associated with purely psychogenic models popular during parts of the 20th century. Neuropsychological studies in recent decades have established the primacy of cognitive functions over psychopathologic symptoms as determinants of functional capacity and independence in everyday functioning. Although the cognitive benefits of both conventional and even second generation antipsychotic medications appear marginal at best, recognition of the primacy of cognitive deficits as determinants of functional disability in schizophrenia has catalyzed recent efforts to develop targeted treatments for the cognitive deficits of this disorder. Despite these accomplishments, however, some issues remain to be resolved. Efforts to firmly establish the specific neurocognitive/neuropathologic systems responsible for schizophrenia remain elusive, as do efforts to definitively demonstrate the specific cognitive deficits underlying specific forms of functional impairment. Further progress may be fostered by recent initiatives to integrate neuropsychological studies with experimental neuroscience, perhaps leading to measures of deficits in cognitive processes more clearly associated with specific, identifiable brain systems
Localization and broadband follow-up of the gravitational-wave transient GW150914
A gravitational-wave (GW) transient was identified in data recorded by the Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) detectors on 2015 September 14. The event, initially designated G184098 and later given the name GW150914, is described in detail elsewhere. By prior arrangement, preliminary estimates of the time, significance, and sky location of the event were shared with 63 teams of observers covering radio, optical, near-infrared, X-ray, and gamma-ray wavelengths with ground- and space-based facilities. In this Letter we describe the low-latency analysis of the GW data and present the sky localization of the first observed compact binary merger. We summarize the follow-up observations reported by 25 teams via private Gamma-ray Coordinates Network circulars, giving an overview of the participating facilities, the GW sky localization coverage, the timeline, and depth of the observations. As this event turned out to be a binary black hole merger, there is little expectation of a detectable electromagnetic (EM) signature. Nevertheless, this first broadband campaign to search for a counterpart of an Advanced LIGO source represents a milestone and highlights the broad capabilities of the transient astronomy community and the observing strategies that have been developed to pursue neutron star binary merger events. Detailed investigations of the EM data and results of the EM follow-up campaign are being disseminated in papers by the individual teams
The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the Extended Baryon Oscillation Spectroscopic Survey and from the Second Phase of the Apache Point Observatory Galactic Evolution Experiment
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes the second data release from this phase, and the 14th from SDSS overall (making this Data Release Fourteen or DR14). This release makes the data taken by SDSS-IV in its first two years of operation (2014–2016 July) public. Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey; the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data-driven machine-learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from the SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS web site (www.sdss.org) has been updated for this release and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020 and will be followed by SDSS-V
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Prospects for Observing and Localizing Gravitational-Wave Transients with Advanced LIGO and Advanced Virgo.
We present a possible observing scenario for the Advanced LIGO and Advanced Virgo gravitational-wave detectors over the next decade, with the intention of providing information to the astronomy community to facilitate planning for multi-messenger astronomy with gravitational waves. We determine the expected sensitivity of the network to transient gravitational-wave signals, and study the capability of the network to determine the sky location of the source. We report our findings for gravitational-wave transients, with particular focus on gravitational-wave signals from the inspiral of binary neutron-star systems, which are considered the most promising for multi-messenger astronomy. The ability to localize the sources of the detected signals depends on the geographical distribution of the detectors and their relative sensitivity, and 90% credible regions can be as large as thousands of square degrees when only two sensitive detectors are operational. Determining the sky position of a significant fraction of detected signals to areas of 5 deg2 to 20 deg2 will require at least three detectors of sensitivity within a factor of ∼ 2 of each other and with a broad frequency bandwidth. Should the third LIGO detector be relocated to India as expected, a significant fraction of gravitational-wave signals will be localized to a few square degrees by gravitational-wave observations alone
Binary Black Hole Mergers in the first Advanced LIGO Observing Run
The first observational run of the Advanced LIGO detectors, from September 12, 2015 to January 19, 2016, saw the first detections of gravitational waves from binary black hole mergers. In this paper we present full results from a search for binary black hole merger signals with total masses up to and detailed implications from our observations of these systems. Our search, based on general-relativistic models of gravitational wave signals from binary black hole systems, unambiguously identified two signals, GW150914 and GW151226, with a significance of greater than over the observing period. It also identified a third possible signal, LVT151012, with substantially lower significance, which has a 87% probability of being of astrophysical origin. We provide detailed estimates of the parameters of the observed systems. Both GW150914 and GW151226 provide an unprecedented opportunity to study the two-body motion of a compact-object binary in the large velocity, highly nonlinear regime. We do not observe any deviations from general relativity, and place improved empirical bounds on several high-order post-Newtonian coefficients. From our observations we infer stellar-mass binary black hole merger rates lying in the range . These observations are beginning to inform astrophysical predictions of binary black hole formation rates, and indicate that future observing runs of the Advanced detector network will yield many more gravitational wave detections
Search for Gravitational Waves Associated with Gamma-Ray Bursts during the First Advanced LIGO Observing Run and Implications for the Origin of GRB 150906B
We present the results of the search for gravitational waves (GWs) associated with γ-ray bursts detected during the first observing run of the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO). We find no evidence of a GW signal for any of the 41 γ-ray bursts for which LIGO data are available with sufficient duration. For all γ-ray bursts, we place lower bounds on the distance to the source using the optimistic assumption that GWs with an energy of were emitted within the – Hz band, and we find a median 90% confidence limit of 71 Mpc at 150 Hz. For the subset of 19 short/hard γ-ray bursts, we place lower bounds on distance with a median 90% confidence limit of 90 Mpc for binary neutron star (BNS) coalescences, and 150 and 139 Mpc for neutron star–black hole coalescences with spins aligned to the orbital angular momentum and in a generic configuration, respectively. These are the highest distance limits ever achieved by GW searches. We also discuss in detail the results of the search for GWs associated with GRB 150906B, an event that was localized by the InterPlanetary Network near the local galaxy NGC 3313, which is at a luminosity distance of Mpc (z = 0.0124). Assuming the γ-ray emission is beamed with a jet half-opening angle , we exclude a BNS and a neutron star–black hole in NGC 3313 as the progenitor of this event with confidence >99%. Further, we exclude such progenitors up to a distance of 102 Mpc and 170 Mpc, respectively
Observation of Gravitational Waves from a Binary Black Hole Merger
On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave
Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in
frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0 × 10−21. It matches the waveform
predicted by general relativity for the inspiral and merger of a pair of black holes and the ringdown of the
resulting single black hole. The signal was observed with a matched-filter signal-to-noise ratio of 24 and a
false alarm rate estimated to be less than 1 event per 203 000 years, equivalent to a significance greater
than 5.1σ. The source lies at a luminosity distance of 410þ160
−180 Mpc corresponding to a redshift z ¼ 0.09þ0.03 −0.04 .
In the source frame, the initial black hole masses are 36þ5
−4M⊙ and 29þ4
−4M⊙, and the final black hole mass is
62þ4
−4M⊙, with 3.0þ0.5 −0.5M⊙c2 radiated in gravitational waves. All uncertainties define 90% credible intervals.
These observations demonstrate the existence of binary stellar-mass black hole systems. This is the first direct
detection of gravitational waves and the first observation of a binary black hole merger
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