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We summarise processes determining large-scale patterns of distribution and abundance of macroinfauna from Florida to Newfoundland, ~25°N to 52°N, focussing on intertidal and shallow subtidal (~ 5 m depth) muddy sands and sandy muds, habitats with abundant experimental data. Within the theme of geographic distribution of processes, mechanisms and patterns we suggest latitudinal patterns will likely change most as climate changes intensify. Published studies support the following major biogeographic patterns: (1) reduced importance of large disturbance predators north of Cape Cod, driven by latitudinal shifts in thermal regimes; (2) large digging predators from Delaware Bay (39.25°N) southwards dramatically reduce infaunal densities, restricting competitive interactions; (3) disturbance refugia, e.g., Zostera, drive southern spatial patterns; (4) rising seawater temperatures and reduced water clarity limit the extent and diversity of rooted plants in the south and mid-Atlantic; (5) latitudinal changes in tidal regimes result in greater aerial exposure in the north, magnifying latitudinal sea surface temperature changes; (6) ice cover intensifies to the north and (7) the Boston−Washington, DC megalopolis accentuates human signatures through eutrophication between 36.5°N and 42.6°N. Finally, we discuss potential shifts with climate change in these latitudinal patterns and processes.
We have observed the G23 field of the Galaxy AndMass Assembly (GAMA) survey using the Australian Square Kilometre Array Pathfinder (ASKAP) in its commissioning phase to validate the performance of the telescope and to characterise the detected galaxy populations. This observation covers ~48 deg2 with synthesised beam of 32.7 arcsec by 17.8 arcsec at 936MHz, and ~39 deg2 with synthesised beam of 15.8 arcsec by 12.0 arcsec at 1320MHz. At both frequencies, the root-mean-square (r.m.s.) noise is ~0.1 mJy/beam. We combine these radio observations with the GAMA galaxy data, which includes spectroscopy of galaxies that are i-band selected with a magnitude limit of 19.2. Wide-field Infrared Survey Explorer (WISE) infrared (IR) photometry is used to determine which galaxies host an active galactic nucleus (AGN). In properties including source counts, mass distributions, and IR versus radio luminosity relation, the ASKAP-detected radio sources behave as expected. Radio galaxies have higher stellar mass and luminosity in IR, optical, and UV than other galaxies. We apply optical and IR AGN diagnostics and find that they disagree for ~30% of the galaxies in our sample. We suggest possible causes for the disagreement. Some cases can be explained by optical extinction of the AGN, but for more than half of the cases we do not find a clear explanation. Radio sources aremore likely (~6%) to have an AGN than radio quiet galaxies (~1%), but the majority of AGN are not detected in radio at this sensitivity.
We explored how positive and negative life experiences of caregivers are associated with household food insecurity.
The Midlands Family Study (MFS) was a cross-sectional study with three levels of household food security: food secure, food insecure without child hunger and food insecure with child hunger. Ordinal logistic regression analysis was used for analyses of negative and positive life experiences (number, impact, type) associated with food insecurity.
An eight-county region in South Carolina, USA, in 2012–2013.
Caregivers (n 511) in households with children.
Caregivers who reported greater numbers of negative life experiences and greater perceived impact had increased odds of household food insecurity and reporting their children experienced hunger. Each additional negative life experience count of the caregiver was associated with a 16 % greater odds of food insecurity without child hunger and a 28 % greater odds of child hunger. Each one-unit increase in the negative impact score (e.g. a worsening) was associated with 8 % higher odds of food insecurity without child hunger and 12 % higher odds of child hunger. Negative work experiences or financial instability had the strongest association (OR = 1·8; 95 % CI 1·5, 2·2) with child hunger. Positive life experiences were generally not associated with food security status, with one exception: for each unit increase in the number of positive experiences involving family and other relationships, the odds of child hunger decreased by 22 %.
More research is needed to understand approaches to build resilience against negative life experiences and strengthen positive familial, community and social relationships.
This paper uses a data set of freehold land and property transactions from medieval England to highlight the growing commercialization of the economy during that time. By drawing on the legal records, we are able to demonstrate that the medieval real estate market provided the opportunity for investors to profit. Careful analysis of the data provides evidence of group purchases, multiple transactions, and investors buying outside their own localities. The identification of these “investors” and their buying behaviors, set within the context of the English medieval economy, contributes to the early commercialization debate.
A robust biomedical informatics infrastructure is essential for academic health centers engaged in translational research. There are no templates for what such an infrastructure encompasses or how it is funded. An informatics workgroup within the Clinical and Translational Science Awards network conducted an analysis to identify the scope, governance, and funding of this infrastructure. After we identified the essential components of an informatics infrastructure, we surveyed informatics leaders at network institutions about the governance and sustainability of the different components. Results from 42 survey respondents showed significant variations in governance and sustainability; however, some trends also emerged. Core informatics components such as electronic data capture systems, electronic health records data repositories, and related tools had mixed models of funding including, fee-for-service, extramural grants, and institutional support. Several key components such as regulatory systems (e.g., electronic Institutional Review Board [IRB] systems, grants, and contracts), security systems, data warehouses, and clinical trials management systems were overwhelmingly supported as institutional infrastructure. The findings highlighted in this report are worth noting for academic health centers and funding agencies involved in planning current and future informatics infrastructure, which provides the foundation for a robust, data-driven clinical and translational research program.
The aim of this study was to characterise changes in lean soft tissue (LST) and examine the contributions of energy intake, physical activity and breast-feeding practices to LST changes at 3 and 9 months postpartum. We examined current weight, LST (via dual-energy X-ray absorptiometry), dietary intake (3-d food diary), physical activity (Baecke questionnaire) and breast-feeding practices (3-d breast-feeding diary) in forty-nine women aged 32·9 (sd 3·8) years. Changes in LST varied from −2·51 to +2·50 kg with twenty-nine women gaining LST (1·1 (sd 0·7) kg, P<0·001) and twenty women losing LST (−0·9 (sd 0·8) kg, P<0·001). Energy intake (133 (SD 42) v. 109 (SD 33) kJ/kg, P=0·019) and % kJ from fat at 3 months postpartum was higher in women who gained LST at 9 months postpartum (gained LST=34 (sd 5) % kJ; lost LST=29 (sd 4) % kJ, P=0·002). Women who gained LST reported breast-feeding their infants more frequently (gained LST=8 (sd 3) feeds/d; lost LST=5 (sd 1) feeds/d, P=0·014) and for more time per d (gained LST=115 (sd 78) min/d; lost LST=59 (sd 34) min/d, P=0·016) at 9 months postpartum. Energy intake and % kJ from fat at 3 months were significant predictors of LST gain (β=0·08 (se 0·04) and 0·24 (se 0·09), respectively). This suggests that gain in LST may be associated with more frequent and longer episodes of breast-feeding at 9 months postpartum as well as dietary intake early in the postpartum period.
Concentrate inclusion levels in dairy cow diets are often adjusted so that the milk yield responses remain economic. While changes in concentrate level on performance is well known, their impact on other biological parameters, including immune function, is less well understood. The objective of this study was to evaluate the effect of concentrate inclusion level in a grass silage-based mixed ration on immune function. Following calving 63 (45 multiparous and 18 primiparous) Holstein Friesian dairy cows were allocated to one of three isonitrogenous diets for the first 70 days of lactation. Diets comprised of a mixture of concentrates and grass silage, with concentrates comprising either a low (30%, LC), medium (50%, MC) or high (70%, HC) proportion of the diet on a dry matter (DM) basis. Daily DM intakes, milk yields and BW were recorded, along with weekly body condition score, milk composition and vaginal mucus scores. Blood biochemistry was measured using a chemistry analyzer, neutrophil phagocytic and oxidative burst assessed using commercial kits and flow cytometry, and interferon-γ production evaluated by ELISA after whole blood stimulation. Over the study period cows on HC had a higher total DM intake, milk yield, fat yield, protein yield, fat+protein yield, protein content, mean BW and mean daily energy balance, and a lower BW loss than cows on MC, whose respective values were higher than cows on LC. Cows on HC and MC had a lower serum non-esterified fatty acid concentration than cows on LC (0.37, 0.37 and 0.50 mmol/l, respectively, P=0.005, SED=0.032), while cows on HC had a lower serum β-hydroxybutyrate concentration than cows on MC and LC (0.42, 0.55 and 0.55 mmol/l, respectively, P=0.002, SED=0.03). Concentrate inclusion level had no effect on vaginal mucus scores. At week 3 postpartum, cows on HC tended to have a higher percentage of oxidative burst positive neutrophils than cows on LC (43.2% and 35.3%, respectively, P=0.078, SED=3.11), although at all other times concentrate inclusion level in the total mixed ration had no effect on neutrophil phagocytic or oxidative burst characteristics, or on interferon-γ production by pokeweed mitogen stimulated whole blood culture. This study demonstrates that for high yielding Holstein Friesian cows managed on a grass silage-based diet, concentrate inclusion levels in early lactation affects performance but has no effect on neutrophil or lymphocyte immune parameters.
Adrian R. Bell, Professor in the History of Finance, Associate Dean (International), and Head of the ICMA Centre at the University of Reading.,
Tony K. Moore, Lecturer in Finance at the ICMA Centre, University of Reading.
Andrew Ayton's research has illuminated our understanding of royal military service by the fourteenth-century aristocracy and how the king drew on existing socio-economic networks to assemble his armies. But what did the Edwardian military community do when there were no royal armies to join? And how were private military activities organised and funded? During the fourteenth and early fifteenth centuries, numerous English magnates and knights, along with their followers, travelled to Prussia to join the Teutonic knights in their campaigns against the pagan (at least until 1386) Lithuanians. The historiography has concentrated on whether these Baltic expeditions can properly be termed crusades or whether they are better viewed as exercises in chivalric vanity. The Baltic excursions of the Western European aristocracy have been described as ‘chivalrous package tours’, a ‘safari’ and even ‘a parade of bored nobles seeking parties and pageantry … and finding excitement in the forests of Lithuania chasing human game’. This essay will not wade into the debate over the relative importance of religious or touristic motivations but will instead focus on how such expeditions were funded and assembled, including the existing and future military links between fellow crusaders.
As we shall see, the evidence concerning English participation in the Baltic crusades is patchy. What there is, including deponent testimony from the Court of Chivalry, suggests that involvement in military campaigns beyond the scope of national warfare was not uncommon and that these expeditionary parties drew upon existing networks. Andrew Ayton has recently stressed the importance of the ‘dynamics of recruitment’, which ‘moulded military service as a social and cultural phenomenon: they explain the incidence of military service – who served, when, where and with whom – and thus the accumulation of actual experience that fuelled fortunes and mentalities, individual and collective’. The investigation of military networks is currently undergoing a transformation as historians begin to use the computational power of relational databases to analyse huge amounts of nominal data. Most historians have concentrated on service in royal armies, for which the surviving evidence is most plentiful, but many of the soldiers who fought for the English kings also took part in expeditions to the Baltic.
Children of parents with psychiatric disorders are at risk of poor outcomes. However, there is limited evidence regarding the relationship between parental psychiatric disorders and child school readiness, which is linked to later academic achievement. This study aims to investigate these relationships and broaden the evidence underlying the rationale for family-focused interventions for parental psychiatric disorders.
This study used linked administrative data. Children's school readiness in multiple developmental domains (physical, social, emotional, communicative, cognitive) was measured by the Australian Early Development Census (AEDC) for 19 071 Western Australian children (mean age 5.5 years). Children scoring in the bottom 25% on any AEDC domain were considered developmentally vulnerable, or at risk of vulnerability, on that domain. Biological child–parent pairs were identified using birth records. Parents with psychiatric disorders were identified from hospital records, which included information on diagnosis and frequency/duration of psychiatric admissions. Logistic regressions, adjusted for parent age, mother's marital status, child Aboriginality, child English language status, local community remoteness and socioeconomic index, estimated the odds of children being vulnerable/at-risk on each of the AEDC domains.
A total of 719 mothers and 417 fathers had a psychiatric hospitalisation during the study period (12 months prior to the child's birth, up to the end of 2009). Children whose parents had psychiatric disorders had increased odds of being classified as vulnerable/at-risk for school readiness. This increase in odds was evident for both maternal (adjusted odds ratio, aOR 1.37– 1.51) and paternal psychiatric disorders (aOR 1.38–1.50); and for a single admission of one day (aOR 1.32–1.59), a single admission of multiple days (aOR 1.30–1.47), and multiple admissions (aOR 1.35–1.63). Some variability in child outcome was found depending on the parents’ psychiatric diagnosis (mood, anxiety, substance abuse or comorbid disorder).
Children of parents who have been hospitalised with psychiatric disorders are at risk for poor school readiness. These findings add support to recommendations that mental health professionals consider dependent children in discharge and treatment planning for adult psychiatric inpatients. It is also important to ensure that the impact of psychiatric illness in fathers is not overlooked in assessment and intervention. Family-based approaches to adult psychiatric care could meet the dual needs of intervention for parents and preventative measures for children. These findings can inform policy regarding the importance of integrating and coordinating services to meet the needs of families.
Parasites of the genus Trypanosoma are microorganisms that display wide morphological, biological and genetic variability. Here we present the first description of an isolate of the genus Trypanosoma naturally infecting the tick Amblyomma brasiliense. The ticks were collected from a specimen of Tayassu pecari (Queixada, white-lipped peccary) from the Itatiaia National Park, Itatiaia, Rio de Janeiro, Brazil. The isolate was characterized by molecular, morphometric and biological analyses. A Trypanosoma culture was isolated from crushed nymphal and adult ticks, propagated in the tick cell line IDE8 and maintained in L15B culture medium, incubated at 32 °C. The isolate grew well in L15B medium at 30, 32 and 34 °C but not at lower or higher temperatures. The culture remained stable in axenic L15B medium at 30 °C. Cryopreserved cultures retained viability after cryopreservation in liquid nitrogen. Growth in axenic medium and developmental forms of the trypanosomes were analysed. Analysis of the 18S rDNA region confirmed the authenticity of this new species and the nucleotide sequence was deposited in Genbank. The species was named Trypanosoma amblyommi sp. nov. strain C1RJ. Characteristics related to pathogenicity, involvement with vertebrate hosts, epidemiology, developmental cycle and transmission mechanisms are still unknown. Therefore, further studies are necessary to understand the aspects of the biological cycle of T. amblyommi sp. nov.
Diet manipulation and genetic selection are two important mitigation strategies for reducing enteric methane (CH4) emissions from ruminant livestock. The aim of this study was to assess whether the diurnal pattern of CH4 emissions from individual dairy cows changes over time when cows are fed on diets varying in forage composition. Emissions of CH4 from 36 cows were measured during milking in an automatic (robotic) milking station in three consecutive feeding periods, for a total of 84 days. In Periods 1 and 2, the 36 cows were fed a high-forage partial mixed ration (PMR) containing 75% forage, with either a high grass silage or high maize silage content. In Period 3, cows were fed a commercial PMR containing 69% forage. Cows were offered PMR ad libitum plus concentrates during milking and CH4 emitted by individual cows was sampled during 8662 milkings. A linear mixed model was used to assess differences among cows, feeding periods and time of day. Considerable variation was observed among cows in daily mean and diurnal patterns of CH4 emissions. On average, cows produced less CH4 when fed on the commercial PMR in feeding Period 3 than when the same cows were fed on high-forage diets in feeding Periods 1 and 2. The average diurnal pattern for CH4 emissions did not significantly change between feeding periods and as lactation progressed. Emissions of CH4 were positively associated with dry matter (DM) intake and forage DM intake. It is concluded that if the management of feed allocation remains constant then the diurnal pattern of CH4 emissions from dairy cows will not necessarily alter over time. A change in diet composition may bring about an increase or decrease in absolute emissions over a 24-h period without significantly changing the diurnal pattern unless management of feed allocation changes. These findings are important for CH4 monitoring techniques that involve taking measurements over short periods within a day rather than complete 24-h observations.
The goal of the present study was to use a methodology that accurately and reliably describes the availability, price and quality of healthy foods at both the store and community levels using the Nutrition Environment Measures Survey in Stores (NEMS-S), to propose a spatial methodology for integrating these store and community data into measures for defining objective food access.
Two hundred and sixty-five retail food stores in and within 2 miles (3·2 km) of Flint, Michigan, USA, were mapped using ArcGIS mapping software.
A survey based on the validated NEMS-S was conducted at each retail food store. Scores were assigned to each store based on a modified version of the NEMS-S scoring system and linked to the mapped locations of stores. Neighbourhood characteristics (race and socio-economic distress) were appended to each store. Finally, spatial and kernel density analyses were run on the mapped store scores to obtain healthy food density metrics.
Regression analyses revealed that neighbourhoods with higher socio-economic distress had significantly lower dairy sub-scores compared with their lower-distress counterparts (β coefficient=−1·3; P=0·04). Additionally, supermarkets were present only in neighbourhoods with <60 % African-American population and low socio-economic distress. Two areas in Flint had an overall NEMS-S score of 0.
By identifying areas with poor access to healthy foods via a validated metric, this research can be used help local government and organizations target interventions to high-need areas. Furthermore, the methodology used for the survey and the mapping exercise can be replicated in other cities to provide comparable results.
Parasites of the genus Trypanosoma are unicellular flagellated microorganisms of the Trypanosomatidae. This study describes an isolate of the genus Trypanosoma naturally infecting Rhipicephalus microplus ticks, characterized through molecular, morphological and biological analysis. Trypanosome cultures, designated strain P1RJ, were obtained by isolation from R. microplus haemolymph in cultures of the tick cell line IDE8. After isolation, strain P1RJ grew well axenically in L15B medium at temperatures of 30, 32 and 34 °C. The new trypanosome remained stable in axenic culture over 14 passages in L15B at 30 °C and was successfully cryopreserved and resuscitated. Morphometric analysis was performed on randomly selected developmental forms. 18S rRNA and 24Sα rDNA sequence analyses confirmed that strain P1RJ is a new species of the genus Trypanosoma. The nucleotide sequences described were submitted to Genbank. Pathogenicity, involvement in vertebrate hosts, epidemiology, developmental cycle and transmission mechanisms of strain P1RJ are still unknown. Therefore, more studies will be necessary to determine life cycle aspects of this trypanosome, for which we propose the name Trypanosoma rhipicephalis sp. nov.
The Murchison Widefield Array (MWA), located in Western Australia, is one of the low-frequency precursors of the international Square Kilometre Array (SKA) project. In addition to pursuing its own ambitious science programme, it is also a testbed for wide range of future SKA activities ranging from hardware, software to data analysis. The key science programmes for the MWA and SKA require very high dynamic ranges, which challenges calibration and imaging systems. Correct calibration of the instrument and accurate measurements of source flux densities and polarisations require precise characterisation of the telescope’s primary beam. Recent results from the MWA GaLactic Extragalactic All-sky Murchison Widefield Array (GLEAM) survey show that the previously implemented Average Embedded Element (AEE) model still leaves residual polarisations errors of up to 10–20% in Stokes Q. We present a new simulation-based Full Embedded Element (FEE) model which is the most rigorous realisation yet of the MWA’s primary beam model. It enables efficient calculation of the MWA beam response in arbitrary directions without necessity of spatial interpolation. In the new model, every dipole in the MWA tile (4 × 4 bow-tie dipoles) is simulated separately, taking into account all mutual coupling, ground screen, and soil effects, and therefore accounts for the different properties of the individual dipoles within a tile. We have applied the FEE beam model to GLEAM observations at 200–231 MHz and used false Stokes parameter leakage as a metric to compare the models. We have determined that the FEE model reduced the magnitude and declination-dependent behaviour of false polarisation in Stokes Q and V while retaining low levels of false polarisation in Stokes U.
Objectives: Medical devices are ubiquitous in modern medical care. However, little is known about the epidemiology of medical devices in the healthcare marketplace, including the rate at which medical devices are subject to recalls or other advisories. We sought to study the epidemiology of medical devices in Canada, focusing on device recalls. In Canada, a recall may signify a variety of events, ranging from relatively minor field safety notifications, to removal of a product from the marketplace.
Methods: We used data from Health Canada to study medical device recalls in Canada from 2005 to 2015. We analyzed the risks of medical device recalls according to the risk class of the device (I lowest; IV highest) and the hazard priority of the recall (Type I highest potential harm; Type III lowest potential harm).
Results: During a 10-year period, there were 7,226 medical device recalls. Most recalls were for intermediate risk class (Class II, 40.1 percent; Class III, 38.7 percent) medical devices. Among recalled devices, 5.0 percent were judged to have a reasonable probability of serious adverse health consequences or death (Type I recall Hazard Priority classification). While the number of medical devices marketed in Canada is not known, over a similar 10-year period, 24,849 new Class II, II, and IV medical device licenses were issued by Health Canada.
Conclusions: Several hundred medical device recalls occur in Canada each year. Further research is needed to characterize the nature of medical device recalls, and to explore how consumers use information about recalls.
A possible cause for accelerated thinning and break-up of floating marine ice shelves is warming of the water in the cavity below the ice shelf. Accurate bathymetry beneath large ice shelves is crucial for developing models of the ocean circulation in the sub-ice cavities. A grid of free-air gravity data over the floating Larsen C ice shelf collected during the IceBridge 2009 Antarctic campaign was utilized to develop the first bathymetry model of the underlying continental shelf. Independent control on the continental shelf geologic structures from marine surveys was used to constrain the inversion. Depths on the continental shelf beneath the ice shelf estimated from the inversion generally range from about 350 to 650 m, but vary from <300 to >1000 m. Localized overdeepenings, 20-30 km long and 900-1000 m deep, are located in inlets just seaward of the grounding line. Submarine valleys extending seaward from the overdeepenings coalesce into two broad troughs that extend to the seaward limit of the ice shelf and appear to extend to the edge of the continental shelf. The troughs are generally at a depth of 550-700 m although the southernmost mapped trough deepens to over 1000 m near the edge of the ice shelf just south of 68° S. The combination of the newly determined bathymetry with published ice-draft determinations based on laser altimetry and radar data defines the geometry of the water-filled cavity. These newly imaged troughs provide a conduit for water to traverse the continental shelf and interact with the overlying Larsen C ice shelf and the grounding lines of the outlet glaciers.
Recent theories suggest that poor working memory (WM) may be the cognitive underpinning of negative symptoms in people with schizophrenia. In this study, we first explore the effect of cognitive remediation (CR) on two clusters of negative symptoms (i.e. expressive and social amotivation), and then assess the relevance of WM gains as a possible mediator of symptom improvement.
Data were accessed for 309 people with schizophrenia from the NIMH Database of Cognitive Training and Remediation Studies and a separate study. Approximately half the participants received CR and the rest were allocated to a control condition. All participants were assessed before and after therapy and at follow-up. Expressive negative symptoms and social amotivation symptoms scores were calculated from the Positive and Negative Syndrome Scale. WM was assessed with digit span and letter-number span tests.
Participants who received CR had a significant improvement in WM scores (d = 0.27) compared with those in the control condition. Improvements in social amotivation levels approached statistical significance (d = −0.19), but change in expressive negative symptoms did not differ between groups. WM change did not mediate the effect of CR on social amotivation.
The results suggest that a course of CR may benefit behavioural negative symptoms. Despite hypotheses linking memory problems with negative symptoms, the current findings do not support the role of this cognitive domain as a significant mediator. The results indicate that WM improves independently from negative symptoms reduction.
Megafossils and macrofossils of terrestrial plants (trees, leaves, fruiting bodies, etc.) are found in sedimentary and pyroclastic units interbedded with lavas in many ancient lava fields worldwide, attesting to subaerial environments of eruption and the establishment of viable plant communities during periods of volcanic quiescence. Preservation within lava is relatively rare and generally confined to the more robust woody tissues of trees, which are then revealed in the form of charcoal, mineralised tissue or as trace fossil moulds (tree moulds) and casts of igneous rock (tree casts, s.s.).
In this contribution, we document several such fossil trees (s.l.), and the lavas with which they are associated, from the Palaeocene Mull Lava Field (MLF) on the Isle of Mull, NW Scotland. We present the first detailed geological account of a unique site within the Mull Plateau Lava Formation (MPLF) at Quinish in the north of the island and provide an appraisal of the famous upright fossil tree – MacCulloch's Tree – remotely located on the Ardmeanach Peninsula on the west coast of the island, and another large upright tree (the Carsaig Tree) near Malcolm's Point in the district of Brolass, SW Mull; both occurring within the earlier Staffa Lava Formation (SLF). The taphonomy of these megafossils, along with palynological and lithofacies assessments of associated strata, allows speculation of likely taxonomic affinity and the duration of hiatuses supporting the establishment of forest/woodland communities. The Ardmeanach and Carsaig specimens, because of their size and preservation as upright (? in situ) casts enveloped by spectacularly columnar-jointed basaltic lava, appear to be unique. The aspect of these trees, the thickness of the enveloping lavas and the arrangement of cooling joints adjacent to the trees, implies rapid emplacement, ponding and slow, static cooling of voluminous and highly fluid basaltic magma. The specimens from Quinish include two prostrate casts and several prostrate moulds that collectively have a preferred orientation, aligning approximately perpendicular to that of the regional Mull Dyke Swarm, the putative fissure source of the lavas, suggesting local palaeo-flow was directed towards the WSW. The Quinish Lava is an excellent example of a classic pāhoehoe (compound-braided) type, preserving some of the best examples of surface and internal features so far noted from the Hebridean Igneous Province (HIP) lava fields.
These Mull megafossils are some of the oldest recorded examples, remarkably well preserved, and form a significant feature of the island's geotourism industry.
The current generation of experiments aiming to detect the neutral hydrogen signal from the Epoch of Reionisation (EoR) is likely to be limited by systematic effects associated with removing foreground sources from target fields. In this paper, we develop a model for the compact foreground sources in one of the target fields of the MWA’s EoR key science experiment: the ‘EoR1’ field. The model is based on both the MWA’s GLEAM survey and GMRT 150 MHz data from the TGSS survey, the latter providing higher angular resolution and better astrometric accuracy for compact sources than is available from the MWA alone. The model contains 5 049 sources, some of which have complicated morphology in MWA data, Fornax A being the most complex. The higher resolution data show that 13% of sources that appear point-like to the MWA have complicated morphology such as double and quad structure, with a typical separation of 33 arcsec. We derive an analytic expression for the error introduced into the EoR two-dimensional power spectrum due to peeling close double sources as single point sources and show that for the measured source properties, the error in the power spectrum is confined to high k⊥ modes that do not affect the overall result for the large-scale cosmological signal of interest. The brightest 10 mis-modelled sources in the field contribute 90% of the power bias in the data, suggesting that it is most critical to improve the models of the brightest sources. With this hybrid model, we reprocess data from the EoR1 field and show a maximum of 8% improved calibration accuracy and a factor of two reduction in residual power in k-space from peeling these sources. Implications for future EoR experiments including the SKA are discussed in relation to the improvements obtained.