Publications by authors named "Heywood I"

Variation in an upstream repetitive region at the locus, which encodes the serotonin transporter, is associated with anxiety-related behaviour in a few primate species, including humans and rhesus macaques, and has been suggested to be related to ecological adaptability among macaques. In this study, we investigate evolution of polymorphisms associated with anxiety-related behaviour in common marmosets (). Assaying variation in the repeat region across 14 species in eight genera of callitrichid primates (marmosets and tamarins), we find large interspecific variation in the number of repeats present (24-43).

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Several long-period radio transients have recently been discovered, with strongly polarized coherent radio pulses appearing on timescales between tens to thousands of seconds. In some cases, the radio pulses have been interpreted as coming from rotating neutron stars with extremely strong magnetic fields, known as magnetars; the origin of other, occasionally periodic and less-well-sampled radio transients is still debated. Coherent periodic radio emission is usually explained by rotating dipolar magnetic fields and pair-production mechanisms, but such models do not easily predict radio emission from such slowly rotating neutron stars and maintain it for extended times.

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The radio-emitting neutron star population encompasses objects with spin periods ranging from milliseconds to tens of seconds. As they age and spin more slowly, their radio emission is expected to cease. We present the discovery of an ultra-long period radio-emitting neutron star, PSR J0901-4046, with spin properties distinct from the known spin and magnetic-decay powered neutron stars.

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Long-duration γ-ray bursts (GRBs) originate from ultra-relativistic jets launched from the collapsing cores of dying massive stars. They are characterized by an initial phase of bright and highly variable radiation in the kiloelectronvolt-to-megaelectronvolt band, which is probably produced within the jet and lasts from milliseconds to minutes, known as the prompt emission. Subsequently, the interaction of the jet with the surrounding medium generates shock waves that are responsible for the afterglow emission, which lasts from days to months and occurs over a broad energy range from the radio to the gigaelectronvolt bands.

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In the past two decades, high-amplitude electromagnetic outbursts have been detected from dormant galaxies and often attributed to the tidal disruption of a star by the central black hole. X-ray emission from the Seyfert 2 galaxy GSN 069 (2MASX J01190869-3411305) at a redshift of z = 0.018 was first detected in July 2010 and implies an X-ray brightening by a factor of more than 240 over ROSAT observations performed 16 years earlier.

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The Galactic Centre contains a supermassive black hole with a mass of four million Suns within an environment that differs markedly from that of the Galactic disk. Although the black hole is essentially quiescent in the broader context of active galactic nuclei, X-ray observations have provided evidence for energetic outbursts from its surroundings. Also, although the levels of star formation in the Galactic Centre have been approximately constant over the past few hundred million years, there is evidence of increased short-duration bursts, strongly influenced by the interaction of the black hole with the enhanced gas density present within the ring-like central molecular zone at Galactic longitude |l| < 0.

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Background: Domestic violence and abuse (DVA) is a serious public health issue, threatening the health of individuals the world over. Whilst DVA can be experienced by both men and women, the majority is still experienced by women; around 30% of women worldwide who have been in a relationship report that they have experienced violence at the hands of their partner, and every week in England and Wales two women are killed by their current or ex-partner. The purpose of this study was to explore the concept of thrivership with women who have experienced DVA, to contribute to our understandings of what constitutes 'thriving' post-abuse, and how women affected can move from surviving to thriving.

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Galaxies are believed to evolve through merging, which should lead to some hosting multiple supermassive black holes. There are four known triple black hole systems, with the closest black hole pair being 2.4 kiloparsecs apart (the third component in this system is at 3 kiloparsecs), which is far from the gravitational sphere of influence (about 100 parsecs for a black hole with mass one billion times that of the Sun).

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Relativistic jets are streams of plasma moving at appreciable fractions of the speed of light. They have been observed from stellar-mass black holes (~3 to 20 solar masses, M(⊙)) as well as supermassive black holes (~10(6) to 10(9) M(⊙)) found in the centers of most galaxies. Jets should also be produced by intermediate-mass black holes (~10(2) to 10(5) M(⊙)), although evidence for this third class of black hole has, until recently, been weak.

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