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Despite increased focus on ascertaining the status of elasmobranch fish, the stock units for many species are uncertain. Data from mark-recapture tagging studies undertaken from 1959–2017 were analysed for 13 batoid species. Data were most comprehensive for skates (Rajidae), with 22,374 released and 3342 (14.9%) returned. Most data related to thornback ray Raja clavata, blonde ray R. brachyura and spotted ray R. montagui. Tags were generally returned from areas less than 50 km from their release, and usually from the ICES Division in which they were released. However, straight-line distances travelled of up to 910 km (R. brachyura) and 772 km (R. clavata) were recorded, highlighting that individual skates are capable of longer-distance movements. The maximum time at liberty was 16.6 years (R. clavata). Whilst mark-recapture data indicated that the current stock units used by ICES are broadly appropriate, southward movements of several skate species tagged off Northern Ireland (Division 6.a) to the Irish Sea (Division 7.a) were observed. In contrast, skates tagged in the Irish Sea and Bristol Channel (Division 7.f) generally remained in that area, with only occasional recaptures from Division 6.a.
In the capital structure literature, speed of adjustment (SOA) estimates are similar whether book or market leverage is used. This robustness is suspect, given the survey evidence that firms target their book leverage and the empirical evidence that they don’t issue securities to offset market leverage changes caused by stock price changes. We show that existing market SOA estimates are substantially upward biased due to the passive influence of stock price fluctuations. Controlling for this bias, the SOA estimate is 16% for book leverage and 10% for market leverage, implying that the trade-off theory is less important than previously thought.
We conducted signal detection analyses to test for curvilinear, U-shaped relations between early experiences of adversity and heightened physiological responses to challenge, as proposed by biological sensitivity to context theory. Based on analysis of an ethnically diverse sample of 338 kindergarten children (4–6 years old) and their families, we identified levels and types of adversity that, singly and interactively, predicted high (top 25%) and low (bottom 25%) rates of stress reactivity. The results offered support for the hypothesized U-shaped curve and conceptually replicated and extended the work of Ellis, Essex, and Boyce (2005). Across both sympathetic and adrenocortical systems, a disproportionate number of children growing up under conditions characterized by either low or high adversity (as indexed by restrictive parenting, family stress, and family economic condition) displayed heightened stress reactivity, compared with peers growing up under conditions of moderate adversity. Finally, as hypothesized by the adaptive calibration model, a disproportionate number of children who experienced exceptionally stressful family conditions displayed blunted cortisol reactivity to stress.
England has recently started a new paediatric influenza vaccine programme using a live-attenuated influenza vaccine (LAIV). There is uncertainty over how well the vaccine protects against more severe end-points. A test-negative case–control study was used to estimate vaccine effectiveness (VE) in vaccine-eligible children aged 2–16 years of age in preventing laboratory-confirmed influenza hospitalisation in England in the 2015–2016 season using a national sentinel laboratory surveillance system. Logistic regression was used to estimate the VE with adjustment for sex, risk-group, age group, region, ethnicity, deprivation and month of sample collection. A total of 977 individuals were included in the study (348 cases and 629 controls). The overall adjusted VE for all study ages and vaccine types was 33.4% (95% confidence interval (CI) 2.3–54.6) after adjusting for age group, sex, index of multiple deprivation, ethnicity, region, sample month and risk group. Risk group was shown to be an important confounder. The adjusted VE for all influenza types for the live-attenuated vaccine was 41.9% (95% CI 7.3–63.6) and 28.8% (95% CI −31.1 to 61.3) for the inactivated vaccine. The study provides evidence of the effectiveness of influenza vaccination in preventing hospitalisation due to laboratory-confirmed influenza in children in 2015–2016 and continues to support the rollout of the LAIV childhood programme.
Unfavourable dietary habits, such as skipping breakfast, are common among ethnic minority children and may contribute to inequalities in cardiometabolic disease. We conducted a longitudinal follow-up of a subsample of the UK multi-ethnic Determinants of Adolescent Social well-being and Health cohort, which represents the main UK ethnic groups and is now aged 21–23 years. We aimed to describe longitudinal patterns of dietary intake and investigate their impact on cardiometabolic risk in young adulthood. Participants completed a dietary behaviour questionnaire and a 24 h dietary intake recall; anthropometry, blood pressure, total cholesterol and HDL-cholesterol and HbA1c were measured. The cohort consisted of 107 White British, 102 Black Caribbean, 132 Black African, 98 Indian, 111 Bangladeshi/Pakistani and 115 other/mixed ethnicity. Unhealthful dietary behaviours such as skipping breakfast and low intake of fruits and vegetables were common (56, 57 and 63 %, respectively). Rates of skipping breakfast and low fruit and vegetable consumption were highest among Black African and Black Caribbean participants. BMI and cholesterol levels at 21–23 years were higher among those who regularly skipped breakfast at 11–13 years (BMI 1·41 (95 % CI 0·57, 2·26), P=0·001; cholesterol 0·15 (95 % CI –0·01, 0·31), P=0·063) and at 21–23 years (BMI 1·05 (95 % CI 0·22, 1·89), P=0·014; cholesterol 0·22 (95 % CI 0·06, 0·37), P=0·007). Childhood breakfast skipping is more common in certain ethnic groups and is associated with cardiometabolic risk factors in young adulthood. Our findings highlight the importance of targeting interventions to improve dietary behaviours such as breakfast consumption at specific population groups.
The biogeographic histories of parasites and pathogens are infrequently compared with those of free-living species, including their hosts. Documenting the frequency with which parasites and pathogens disperse across geographic regions contributes to understanding not only their evolution, but also the likelihood that they may become emerging infectious diseases. Haemosporidian parasites of birds (parasite genera Plasmodium, Haemoproteus and Leucocytozoon) are globally distributed, dipteran-vectored parasites. To date, over 2000 avian haemosporidian lineages have been designated by molecular barcoding methods. To achieve their current distributions, some lineages must have dispersed long distances, often over water. Here we quantify such events using the global avian haemosporidian database MalAvi and additional records primarily from the Americas. We scored lineages as belonging to one or more global biogeographic regions based on infection records. Most lineages were restricted to a single region but some were globally distributed. We also used part of the cytochrome b gene to create genus-level parasite phylogenies and scored well-supported nodes as having descendant lineages in regional sympatry or allopatry. Descendant sister lineages of Plasmodium, Haemoproteus and Leucocytozoon were distributed in allopatry in 11, 16 and 15% of investigated nodes, respectively. Although a small but significant fraction of the molecular variance in cytochrome b of all three genera could be explained by biogeographic region, global parasite dispersal likely contributed to the majority of the unexplained variance. Our results suggest that avian haemosporidian parasites have faced few geographic barriers to dispersal over their evolutionary history.
Significant increases in excess all-cause mortality, particularly in the elderly, were observed during the winter of 2014/15 in England. With influenza A(H3N2) the dominant circulating influenza A subtype, this paper determines the contribution of influenza to this excess controlling for weather. A standardised multivariable Poisson regression model was employed with weekly all-cause deaths the dependent variable for the period 2008–2015. Adjusting for extreme temperature, a total of 26 542 (95% CI 25 301–27 804) deaths in 65+ and 1942 (95% CI 1834–2052) in 15–64-year-olds were associated with influenza from week 40, 2014 to week 20, 2015. This is compatible with the circulation of influenza A(H3N2). It is the largest estimated number of influenza-related deaths in England since prior to 2008/09. The findings highlight the potential health impact of influenza and the important role of the annual influenza vaccination programme that is required to protect the population including the elderly, who are vulnerable to a severe outcome.
Post-harvest drying prolongs seed survival in air-dry storage; previous research has shown a benefit of drying moist rice seeds at temperatures greater than recommended for genebanks (5–20°C). The aim of this study was to determine whether there is a temperature limit for safely drying rice seeds, and to explore whether the benefit to longevity is caused by high-temperature stress or continued seed development. Seeds of two rice varieties were harvested at different stages of development and dried initially either over silica gel, or intermittently (8 h day–1) or continuously (24 h day–1) over MgCl2 at temperatures between 15 and 60°C for up to 3 days. Seeds dried more rapidly the warmer the temperature. Subsequent seed longevity in hermetic storage (45°C and 10.9% moisture content) was substantially improved by increase in drying temperature up to 45°C in both cultivars, and also with further increase from 45 to 60°C in cv. ‘Macassane’. The benefit of high-temperature drying to subsequent longevity tended to diminish the later the stage of development at seed harvest. Intermittent or continuous drying at high temperatures provided broadly similar improvements to longevity, but with the greatest improvements detected in a few treatment combinations with continuous drying. Heated-air drying of rice seeds harvested before maturity improved their subsequent storage longevity by more than that which occurred during subsequent development in planta, which may have resulted from the triggering of protection mechanisms in response to high-temperature stress.
In-spiraling supermassive black holes should emit gravitational waves, which would produce characteristic distortions in the time of arrival residuals from millisecond pulsars. Multiple national and regional consortia have constructed pulsar timing arrays by precise timing of different sets of millisecond pulsars. An essential aspect of precision timing is the transfer of the times of arrival to a (quasi-)inertial frame, conventionally the solar system barycenter. The barycenter is determined from the knowledge of the planetary masses and orbits, which has been refined over the past 50 years by multiple spacecraft. Within the North American Nanohertz Observatory for Gravitational Waves (NANOGrav), uncertainties on the solar system barycenter are emerging as an important element of the NANOGrav noise budget. We describe what is known about the solar system barycenter, touch upon how uncertainties in it affect gravitational wave studies with pulsar timing arrays, and consider future trends in spacecraft navigation.
We present the concept of a novel facility dedicated to massively-multiplexed spectroscopy. The telescope has a very wide field Cassegrain focus optimised for fibre feeding. With a Field of View (FoV) of 2.5 degrees diameter and a 11.4m pupil, it will be the largest etendue telescope. The large focal plane can easily host up to 16.000 fibres. In addition, a gravity invariant focus for the central 10 arc-minutes is available to host a giant integral field unit (IFU). The 3 lenses corrector includes an ADC, and has good performance in the 360-1300 nm wavelength range. The top level science requirements were developed by a dedicated ESO working group, and one of the primary cases is high resolution spectroscopy of GAIA stars and, in general, how our Galaxy formed and evolves. The facility will therefore be equipped with both, high and low resolution spectrographs. We stress the importance of developing the telescope and instrument designs simultaneously. The most relevant R&D aspect is also briefly discussed.
Unusual speleothems, associated with hyperalkaline (pH > 12) groundwaters
have formed within a shallow, abandoned railway tunnel at Peak Dale,
Derbyshire, UK. The hyperalkaline groundwaters are produced by the leaching
of a thin layer (<2 m) of old lime-kiln waste on the soil-bedrock surface
above the tunnel by rainwater. This results in a different reaction and
chemical process to that more commonly associated with the formation of
calcium carbonate speleothems from Ca-HCO3-type groundwaters and
degassing of CO2. Stalagmites within the Peak Daletunnel have
grown rapidly (averaging 33 mm y–1), following the closure of the
tunnel 70 years ago. They have an unusual morphology comprising a central
sub-horizontally-laminated column of micro- to nano-crystalline calcium
carbonate encompassed by an outer sub-vertical assymetricripple-laminated
layer. The stalagmites are composed largely of secondary calcite forming
pseudomorphs (<1 mm) that we believe to be predominantly after the 'cold
climate' calcium carbonate polymorph, ikaite (calcium carbonate hexahydrate:
CaCO3·6H2O), withminor volumes of small (<5 μm)
pseudomorphs after vaterite. The tunnel has a near constant temperature of
8–9°C, which is slightly above the previously published crystallization
temperatures for ikaite (<6°C). Analysis of a stalagmite actively growing
at the time ofsampling, and preserved immediately within a dry nitrogen
cryogenic vessel, indicates that following crystallization of ikaite,
decomposition to calcite occurs rapidly, if not instantaneously. We believe
this is the first occurrence of this calcium carbonate polymorph observed
This chapter is about foundational themes underlying the scientific study of cosmology:
• What issues will a theory of cosmology deal with?
• What kinds of causation will be taken into account as we consider the relation between chance and necessity in cosmology?
• What kinds of data and arguments will we use to test theories, when they stretch beyond the bounds of observational probing?
• Should we weaken the need for testing and move to a post-empirical phase, as some have suggested?
These are philosophical issues at the foundation of the cosmological enterprise. The answer may be obvious or taken for granted by scientists in many cases, and so seem hardly worth mentioning; but that has demonstrably led to some questionable statements about what is reliably known about cosmology, particularly in popular books and public statements. The premise of this chapter is that it is better to carefully think these issues through and make them explicit, rather than having unexamined assumed views about them shaping cosmological theories and their public presentation. Thus, as in other subjects, being philosophical about what is being undertaken will help clarify practice in the area.
The basic enterprise of cosmology is to use tested physical theories to understand major aspects of the universe in which we live, as observed by telescopes of all kinds. The foundational issue arising is the uniqueness of the universe [66, 27, 28]. Standard methods of scientific theory testing rely on comparing similar objects to determine regularities, so they cannot easily be applied in the cosmological context, where there is no other similar object to use in any comparison. We have to extrapolate from aspects of the universe to hypotheses about the seen and unseen universe as a whole. Furthermore, physical explanations of developments in the very early universe depend on extrapolating physical theories beyond the bounds where they can be tested in a laboratory or particle collider. Hence philosophical issues of necessity arise as we push the theory beyond its testable limits. Making them explicit clarifies what is being done and illuminates issues that need careful attention.
In autumn 2014, enterovirus D68 (EV-D68) cases presenting with severe respiratory or neurological disease were described in countries worldwide. To describe the epidemiology and virological characteristics of EV-D68 in England, we collected clinical information on laboratory-confirmed EV-D68 cases detected in secondary care (hospitals), between September 2014 and January 2015. In primary care (general practitioners), respiratory swabs collected (September 2013–January 2015) from patients presenting with influenza-like illness were tested for EV-D68. In secondary care 55 EV-D68 cases were detected. Among those, 45 cases had clinical information available and 89% (40/45) presented with severe respiratory symptoms. Detection of EV-D68 among patients in primary care increased from 0.4% (4/1074; 95% CI 0.1–1.0) (September 2013–January 2014) to 0.8% (11/1359; 95% CI 0.4–1.5) (September 2014–January 2015). Characterization of EV-D68 strains circulating in England since 2012 and up to winter 2014/2015 indicated that those strains were genetically similar to those detected in 2014 in USA. We recommend reinforcing enterovirus surveillance through screening respiratory samples of suspected cases.
To investigate the feasibility of a national audit of epistaxis management led and delivered by a multi-region trainee collaborative using a web-based interface to capture patient data.
Six trainee collaboratives across England nominated one site each and worked together to carry out this pilot. An encrypted data capture tool was adapted and installed within the infrastructure of a university secure server. Site-lead feedback was assessed through questionnaires.
Sixty-three patients with epistaxis were admitted over a two-week period. Site leads reported an average of 5 minutes to complete questionnaires and described the tool as easy to use. Data quality was high, with little missing data. Site-lead feedback showed high satisfaction ratings for the project (mean, 4.83 out of 5).
This pilot showed that trainee collaboratives can work together to deliver an audit using an encrypted data capture tool cost-effectively, whilst maintaining the highest levels of data quality.