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"Lee, K. J."
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Diverse polarization angle swings from a repeating fast radio burst source
Fast radio bursts (FRBs) are millisecond-duration radio transients
1
,
2
of unknown origin. Two possible mechanisms that could generate extremely coherent emission from FRBs invoke neutron star magnetospheres
3
–
5
or relativistic shocks far from the central energy source
6
–
8
. Detailed polarization observations may help us to understand the emission mechanism. However, the available FRB polarization data have been perplexing, because they show a host of polarimetric properties, including either a constant polarization angle during each burst for some repeaters
9
,
10
or variable polarization angles in some other apparently one-off events
11
,
12
. Here we report observations of 15 bursts from FRB 180301 and find various polarization angle swings in seven of them. The diversity of the polarization angle features of these bursts is consistent with a magnetospheric origin of the radio emission, and disfavours the radiation models invoking relativistic shocks.
Polarization observations of the fast radio burst FRB 180301 with the FAST radio telescope show diverse polarization angle swings, consistent with a magnetospheric origin of the emission.
Journal Article
Consensus recommendations on training and competing in the heat
Exercising in the heat induces thermoregulatory and other physiological strain that can lead to impairments in endurance exercise capacity. The purpose of this consensus statement is to provide up-to-date recommendations to optimise performance during sporting activities undertaken in hot ambient conditions. The most important intervention one can adopt to reduce physiological strain and optimise performance is to heat acclimatise. Heat acclimatisation should comprise repeated exercise-heat exposures over 1–2 weeks. In addition, athletes should initiate competition and training in a euhydrated state and minimise dehydration during exercise. Following the development of commercial cooling systems (eg, cooling-vest), athletes can implement cooling strategies to facilitate heat loss or increase heat storage capacity before training or competing in the heat. Moreover, event organisers should plan for large shaded areas, along with cooling and rehydration facilities, and schedule events in accordance with minimising the health risks of athletes, especially in mass participation events and during the first hot days of the year. Following the recent examples of the 2008 Olympics and the 2014 FIFA World Cup, sport governing bodies should consider allowing additional (or longer) recovery periods between and during events, for hydration and body cooling opportunities, when competitions are held in the heat.
Journal Article
Algorithm for the management of patients at low, high and very high risk of osteoporotic fractures
SummaryGuidance is provided in an international setting on the assessment and specific treatment of postmenopausal women at low, high and very high risk of fragility fractures.IntroductionThe International Osteoporosis Foundation and European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis published guidance for the diagnosis and management of osteoporosis in 2019. This manuscript seeks to apply this in an international setting, taking additional account of further categorisation of increased risk of fracture, which may inform choice of therapeutic approach.MethodsClinical perspective and updated literature search.ResultsThe following areas are reviewed: categorisation of fracture risk and general pharmacological management of osteoporosis.ConclusionsA platform is provided on which specific guidelines can be developed for national use to characterise fracture risk and direct interventions.
Journal Article
Intussusception following rotavirus vaccine administration: Post-marketing surveillance in the National Immunization Program in Australia
In Australia, post-marketing surveillance for intussusception following vaccination commenced with funding of
RotaTeq
®
and
Rotarix
®
vaccines under the National Immunization Program (NIP) in July 2007.
Two active surveillance mechanisms (hospital-based case ascertainment and monthly reports from paediatricians) identified intussusception cases between 1st July 2007 and 31st December 2008 in four states. Linkage to vaccination records identified cases occurring within 1–7 and 1–21 days of rotavirus vaccination. Expected cases within the post-vaccination windows were calculated by applying rates of intussusception from national hospitalisation data over 6 years (mid-2000 to mid-2006), by age and state, to numbers vaccinated (by dose) according to the Australian Childhood Immunization Register.
Combining exposure windows associated with all doses of rotavirus vaccine from 1 to 9 months of age, there was no evidence of an increased risk of intussusception following vaccination for either vaccine. However, in infants 1 to <3 months of age, there was suggestive evidence of excess intussusception cases 1–7 and 1–21 days following dose 1 (1–7 days:
RotaTeq
®
relative risk (RR)
=
5.3, 95% confidence interval [CI] 1.1,15.4;
Rotarix
®
RR 3.5, 95% CI 0.7,10.1; 1–21 days:
RotaTeq
®
RR 3.5, 95% CI 1.3, 7.6;
Rotarix
®
RR 1.5, 95% CI 0.4, 3.9). There was no evidence that clinical outcome of intussusception occurring within 21 days of rotavirus vaccination differed from that in cases occurring later post-vaccination.
Although we found no overall increase in intussusception following receipt of rotavirus vaccine, there was some evidence of an elevated risk following the first dose of both vaccines. Larger population-based studies using linked databases are required to provide more definitive evidence.
Journal Article
A strong magnetic field around the supermassive black hole at the centre of the Galaxy
The unusually large Faraday rotation of a newly discovered pulsar indicates that there is a dynamically important magnetic field near the supermassive black hole believed to lie at the centre of the Milky Way.
Strong magnetic field at Galactic Centre
Sagittarius A
*
, at the centre of the Milky Way, harbours a strong candidate for a supermassive black hole. The source is thought to be powered by radiatively inefficient accretion of gas, with magnetic fields possibly helping the flow to occur. In most galaxies the accretion flow cannot be resolved directly and accretion models lack information about the initial conditions of the flow. Ralph Eatough
et al
. have determined magnetic field strength indirectly by measuring the rotation of radio emission from a new pulsar that erupted as an X-ray source near Sag A
*
. The results point to the presence of dynamically important magnetic field near the black hole.
Earth’s nearest candidate supermassive black hole lies at the centre of the Milky Way
1
. Its electromagnetic emission is thought to be powered by radiatively inefficient accretion of gas from its environment
2
, which is a standard mode of energy supply for most galactic nuclei. X-ray measurements have already resolved a tenuous hot gas component from which the black hole can be fed
3
. The magnetization of the gas, however, which is a crucial parameter determining the structure of the accretion flow, remains unknown. Strong magnetic fields can influence the dynamics of accretion, remove angular momentum from the infalling gas
4
, expel matter through relativistic jets
5
and lead to synchrotron emission such as that previously observed
6
,
7
,
8
. Here we report multi-frequency radio measurements of a newly discovered pulsar close to the Galactic Centre
9
,
10
,
11
,
12
and show that the pulsar’s unusually large Faraday rotation (the rotation of the plane of polarization of the emission in the presence of an external magnetic field) indicates that there is a dynamically important magnetic field near the black hole. If this field is accreted down to the event horizon it provides enough magnetic flux to explain the observed emission—from radio to X-ray wavelengths—from the black hole.
Journal Article
Mesh-like structure integrated core-shell-shell nanocomposites for enhanced stability and performance in carbon capture
Carbon capture is essential for mitigating climate change, yet most sorbents struggle to combine high capacity with chemical stability. Here we report core-shell-shell (CSS) nanocomposites that integrate adsorption efficiency with exceptional robustness. The design couples a metal-organic framework (MOF) core, which enriches local CO
2
concentration, with a polyamine shell that is reorganized into a porous, ordered network through entanglement with an outer covalent organic framework (COF) shell. This hierarchical architecture enables dual amine functionalization via sequential “click” and Schiff-base reactions, achieving a CO
2
uptake of 3.4 mmol g
−1
at 1 bar. The COF outer layer also acts as a protective barrier, suppressing humidity interference and doubling cycling stability under simulated flue gas. Remarkably, the nanocomposites maintain structural integrity after one week in strongly acidic (3 M HNO
3
) or basic (NaOH, pH=14) environments, underscoring their chemical resilience. By uniting high capacity, cycling durability, and environmental tolerance, this CSS strategy offers a versatile platform for next-generation carbon capture materials.
The study reports a metal-organic framework (MOF) - covalent organic framework (COF) nanocomposite with dual amine sites that captures CO
2
efficiently and remains stable under humid, harsh conditions, offering a promising path for next-generation carbon capture.
Journal Article