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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.
The focus of community ecology has shifted from the description of taxonomic composition towards an understanding of community assembly based on species’ ‘functional traits’. The functional trait approach is well developed for vascular plants, utilising variability of continuous phenotypic characters that affect ecological fitness, such as specific leaf area, tissue nitrogen concentration or seed mass, to explain community structure. In contrast, community assembly studies for poikilohydric cryptogamic plants and fungi, such as lichens, remain focused on broad categorical traits such as growth form difference: fruticose, foliose or crustose. This study examined intra- and interspecific variability for two highly promising continuous phenotypic measurements that affect lichen physiology and ecological fitness: water-holding capacity (WHC) and specific thallus mass (STM). Values for WHC and STM were compared within and among species, and within and among key macrolichen growth forms (fruticose and green-algal and cyanolichen foliose species), asking whether these widely used categories adequately differentiate the continuous variables (WHC and STM). We show large intra- and interspecific variability that does not map satisfactorily onto growth form categories, and on this basis provide recommendations and caveats in the future use of lichen functional traits.
Giardiasis is one of the most important non-viral causes of human diarrhoea. Yet, little is known about the epidemiology of giardiasis in the context of developed countries such as Australia and there is a limited information about local sources of exposure to inform prevention strategies in New South Wales. This study aimed to (1) describe the epidemiology of giardiasis and (2) identify potential modifiable risk factors associated with giardiasis that are unique to south-western Sydney, Australia. A 1:2 matched case-control study of 190 confirmed giardiasis cases notified to the South-Western Local Health District Public Health Unit from January to December 2016 was employed to investigate the risk factors for giardiasis. Two groups of controls were selected to increase response rate; Pertussis cases and neighbourhood (NBH) controls. A matched analysis was carried out for both control groups separately. Variables with a significant odds ratio (OR) in the univariate analysis were placed into a multivariable regression for each matched group, respectively. In the regression model with the NBH controls, age and sex were controlled as potential confounders. Identified risk factors included being under 5 years of age (aOR = 7.08; 95% confidence intervals (CI) 1.02–49.36), having a household member diagnosed with a gastrointestinal illness (aOR = 15.89; 95% CI 1.53–164.60) and having contact with farm animals, domestic animals or wildlife (aOR = 3.03; 95% CI 1.08–8.54). Cases that travelled overseas were at increased risk of infection (aOR = 19.89; 95% CI 2.00–197.37) when compared with Pertussis cases. This study provides an update on the epidemiology and associated risk factors of a neglected tropical disease, which can inform enhanced surveillance and prevention strategies in the developed metropolitan areas.
Background: Heterozygous loss-of-function mutations in the synaptic scaffolding gene SHANK2 are strongly associated with autism spectrum disorder (ASD). However, their impact on the function of human neurons is unknown. Derivation of induced pluripotent stem cells (iPSC) from affected individuals permits generation of live neurons to answer this question. Methods: We generated iPSCs by reprogramming dermal fibroblasts of neurotypic and ASD-affected donors. To isolate the effect of SHANK2, we used CRISPR/Cas9 to knock out SHANK2 in control iPSCs and correct a heterozygous nonsense mutation in ASD-affected donor iPSCs. We then derived cortical neurons from SOX1+ neural precursor cells differentiated from these iPSCs. Using a novel assay that overcomes line-to-line variability, we compared neuronal morphology, total synapse number, and electrophysiological properties between SHANK2 mutants and controls. Results: Relative to controls, SHANK2 mutant neurons have increased dendrite complexity, dendrite length, total synapse number (1.5-2-fold), and spontaneous excitatory postsynaptic current (sEPSC) frequency (3-7.6-fold). Conclusions: ASD-associated heterozygous loss-of-function mutations in SHANK2 increase synaptic connectivity among human neurons by increasing synapse number and sEPSC frequency. This is partially supported by increased dendrite length and complexity, providing evidence that SHANK2 functions as a suppressor of dendrite branching during neurodevelopment.
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.
Introduction: Emergency departments (ED) across Canada acknowledge the need to transform in order to provide high quality care for the increasing proportion of older patients presenting for treatment. Older people are more complex than younger ED users. They have a disproportionately high use of EDs, increased rates of hospitalization, and are more likely to suffer adverse events. The objective of this initiative was to develop minimum standards for the care of older people in the emergency department. Methods: We created a panel of international leaders in geriatrics and emergency medicine to develop a policy framework on minimum standards for care of older people in the ED. We conducted a literature review of international guidelines, frameworks, recommendations, and best practices for the acute care of older people and developed a draft standards document. This preliminary document was circulated to interdisciplinary members of the International Federation of Emergency Medicine (IFEM) geriatric emergency medicine (GEM) group. Following review, the standards were presented to the IFEM clinical practice group. At each step, verbal, written and online feedback were gathered and integrated into the final minimum standards document. Results: Following the developmental process, a series of eight minimum standard statements were created and accepted by IFEM. These standards utilise the IFEM Framework for Quality and Safety in the ED, and are centred on the recognition that older people are a core population of emergency health service users whose care needs are different from those of children and younger adults. They cover key areas, including the overall approach to older patients, the physical environment and equipment, personnel and training, policies and protocols, and strategies for navigating the health-care continuum. Conclusion: These standards aim to improve the evaluation, management and integration of care of older people in the ED in an effort to improve outcomes. The minimum standards represent a first step on which future activities can be built, including the development of specific indicators for each of the minimum standards. The standards are designed to apply across the spectrum of EDs worldwide, and it is hoped that they will act as a catalyst to change.
At weaning, piglets must adapt to considerable changes in their environmental, immunological, and nutritional status. This period of adaptation is accompanied by a reduction in piglet growth rate that has been associated with the shift from sow’s milk to a solid dry diet. Consequently, feeding management strategies that result in increased feed intake may increase piglet growth rate postweaning. This study evaluated the effects of providing feed as a gruel and feeding on floor mats on piglet performance for three weeks after weaning
The Virology Department, VSD, DARDNI, in collaboration with colleagues in Europe and N America has had an active research programme on porcine circovirus-related diseases, including PMWS, for the last 5 years. This presentation will highlight some of our on-going research in this area.
The Major Histocompatibility Complex (MHC) class I genes encode polymorphic cell surface glycoproteins that initiate cytotoxic immune responses by presenting processed antigenic peptides to CD8+ T cells. Due to their functional role and polymorphic nature, MHC class I genes have been used in disease association and vaccine development studies in many species. A prerequisite for such studies is the availability of animals of defined MHC haplotypes. However, the ovine MHC (OLA) class I genes have been studied largely by serology and very limited information is available at the DNA level (Dietert R., 1996). In this study, we aimed to identify the number of transcribed OLA class I genes in two Blackface rams and to obtain sequence data for exons 2 and 3. These data will be used to establish an allele specific PCR based typing system to genotype a cohort of progeny for each ram. This will enable allocation of alleles to individual haplotypes and inform a breeding strategy for the generation of MHC defined animals for functional and disease association studies.
When emptying finishing barns, it is common practice on U.S. operations to dispatch pigs over a two- to three-week period with the heaviest animals being selected first. However, there has been little research carried out under commercial conditions on the effect of removing pigs from a pen at slaughter weight on the performance of the remaining animals. This study was carried out to investigate the effect of removing the heaviest 30% of animals from a pen on the subsequent growth performance of the remaining pigs.
Wean-to-finish production, which involves taking pigs from weaning to slaughter in the same building, is becoming widely adopted in the US swine industry. This production system is being advocated largely because of claims of improved animal performance and a decrease in labor needed for animal movement compared to conventional multiple-stage systems. One of the potential disadvantages of this system is the considerable underutilization of floor space during the early growth period if pigs are penned in the group sizes that are appropriate for finishing pigs. However, increasing the stocking rate initially at weaning, with some of these pigs subsequently being moved to another finishing facility, may increase output from the system. Therefore, the objective of this research was to investigate effects of initial stocking rate and of feeder-trough space in commercial wean-to-finish facilities on pig performance from weaning to slaughter.
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 have observed 3 moderate redshift clusters using a combination of 7 intermediate band filters and 2 CCDs in order to derive photometric information for cluster galaxies from 400 nm to 900 nm. Preliminary results are presented for 2 clusters: Abell 1942 (z=0.224) and Abell 1525 (z=0.259) from 580 nm to 860 nm. The CCD photometry reaches a limit equivalent to RF=21 mag with a precision of better than 0.1 mag. The galaxy colours derived from the intermediate band measurements are generally consistent with those expected at the appropriate redshift. However, in Abell 1525, and to a lesser extent in Abell 1942, a large proportion of cluster members have far red (720–860 nm) colours redder than expected. Many of these galaxies have blue photographic BJ-RF colours. A possible explanation for the anomalous CCD colours is that these galaxies possess a strong emission line component which enters the far red filter at z=0.25.
The aim of the survey is to sample a relatively large, randomly chosen volume of the Universe in order to study the large-scale distribution of galaxies using the two-point correlation function, the peculiar velocities between galaxy pairs and to provide an estimate of the galaxian luminosity function that is unaffected by density inhomogeneities and Virgo infall.
A global array of 20 radio observatories was used to measure the three-dimensional position and velocity of the two meteorological balloons that were injected into the equatorial region of the Venus atmosphere by the VEGA spacecraft.
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
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.
The Southern Ocean is the largest of the high-nutrient, low-chlorophyll (HNLC) regions of the world ocean. Phytoplankton production fails to utilise completely the pool of inorganic nutrients in the euphotic zone, giving rise to low phytoplankton bio-mass and leaving relatively high summer nutrient concentrations. This enigma is of considerable significance for our understanding of the role of the oceans in the global carbon cycle. Various limiting factors have been considered: low light, low temperature, absence of necessary trace elements, grazing pressure and other means of biomass removal.
The dynamics of nitrogen uptake by phytoplankton are of particular importance. Classically, nitrate mixed into the surface layer during winter provides the nitrogen pool for growth in the spring bloom. Some organic material is exported to depth, whilst the remainder is recycled, providing ammonium and other reduced species as nitrogenous substrates for growth during the remainder of the season. The oxidation state of the inorganic nitrogen supply thus identifies new and recycled carbon fixation. Whilst this is convenient “shorthand” for the nitrogen nutrition of carbon export in much of the ocean, it is an inappropriate model for the Southern Ocean. Here, nitrate and ammonium use are simultaneous, and nitrate is never exhausted by the annual phytoplankton production.
We speculate that a range of environmental factors combine to make the large pool of nitrate partially inaccessible to phytoplankton. in addition to the documented effects of low iron availability and high ammonium concentrations, the low temperatures characteristic of the Southern Ocean may decrease nitrate availability because of the increased energetic overheads in its uptake and reduction. This in turn makes ammonium an important nitrogenous substrate, and its production by zooplankton and heterotrophic microorganisms is an important component of the plankton nitrogen cycle. There is some evidence that ammonium production by large grazing animals may stimulate phytoplankton growth. Microbial removal of nitrogen from sedimenting phytoplankton cells may result in local decoupling between the carbon and nitrogen cycles, allowing some reduced nitrogen to remain in the euphotic zone whilst carbon is exported to depth.