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Recruitment of the limpet Patella ulyssiponensis was investigated in relation to the presence of living crustose coralline algae (CCA) in rocky-shore habitats. Juvenile limpets (≤10 mm maximum shell length) were counted in CCA-present and CCA-absent habitats, on three shores in SW Portugal during summer 2007 and winter 2009. Furthermore, the settling response of laboratory-reared larvae of P. ulyssiponensis to CCA-covered substratum, and bare-rock, was examined. Across the intertidal zone, we found a clear association between the distribution and abundance of juveniles and the presence of CCA. Although the presence of CCA was not an absolute requisite for juvenile occurrence, null juvenile densities were mostly recorded in CCA-absent areas. The highest juvenile densities (maximum of 64 individuals in 15 × 15 cm) were consistently found in CCA-dominated habitats, namely steep wave-exposed areas at low-shore and rock-pools. The hypothesis of CCA-enhanced settlement was not supported, as settlement intensities of laboratory-reared larvae were similar between chips of rock encrusted by CCA and chips of bare-rock. From the overall number of settlers onto CCA-encrusted rock chips, 51% were found in tiny pits lacking CCA. This was the first study of the settlement patterns of larvae of the genus Patella using naturally occurring rocky substrata. These results are preliminary and should be confirmed with choice-experiments and improved monitoring of the position of settlers. We suggest that CCA plays a role in the recruitment of P. ulyssiponensis, potentially promoting survivorship of early benthic stages, but possibly not enhancing settlement.
Limpets and barnacles are important components of intertidal assemblages worldwide. This study examines the effects of barnacles on the foraging behaviour of the limpet Patella vulgata, which is the main algal grazer in the North-west Atlantic. The behaviour of limpets on a vertical seawall on the Isle of Man (UK) was investigated using autonomous radio-telemetry, comparing their activity patterns on plots characterized by dense barnacle cover and plots from which the barnacles had been removed. Limpet behaviour was investigated at mid-shore level, but two different elevations were considered. This experiment revealed a significant effect of barnacle cover on the activity of P. vulgata. Limpets on smooth surfaces spent a greater proportion of total time active than did limpets on barnacles. Movement activity was also greater in areas that were lower down in the tidal range. In general, limpets were either predominantly active during diurnal high or nocturnal low tides and always avoided nocturnal high tides. Individuals on barnacles at the higher elevation concentrated their activity during nocturnal low water. All the other groups of limpets (smooth surfaces on the upper level and all individuals on the lower shore) had more excursions centred around daylight hours with an equal distribution of activity between periods of low and high water. Inter-individual variability was, however, pronounced.
Due to their rareness, it is not known if the clinicopathological features of cerebellar glioblastomas (cGBMs) are different from supratentorial GBMs (sGBMs). We reviewed all 16 cases of cGBMs (total GBMs: 1350) at St. Michael’s Hospital over 18 years and assessed their clinicopathologic features. The mean age at diagnosis was 57 years. The most common presentations were headache (56%) and gait instability (56%). The majority (81%) of cGBMs were hemispheric while 19% involved the midline. There was radiologic evidence of brainstem infiltration at presentation in one case. Radiologically, peritumoral edema (63%) and heterogeneous contrast enhancement (50%) were common. Histologically, cGBM showed leptomeningeal involvement in 10/12 of cases. Uncommon histologic variants included 3 giant cell GBMs, a gliosarcoma, and a tumor with Rosenthal fibres and eosinophilic granular bodies. IDH1 R132H mutation was detected in 3/14 cases, a rate much higher than sGBMs. Additionally, 7/11 tumors had widespread p53 immunopositivity suggestive of TP53 mutation which is in accordance with previous reports in the literature. Of 9 cases tested, none had histone H3 K27M or G34R/V mutation. In summary, cGBMs have unique features that distinguishes them from sGBMs.
This presentation will enable the learner to:
1.Identify the clinicopathological features of cerebellar GBMs including major molecular alterations
2.Compare cerebellar and supratentorial GBMs and describe the distinguishing features of each type of tumor
The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
In September 2015, an outbreak of Escherichia coli Phage Type 32 with an indistinguishable multi locus variable number tandem repeat analysis profile was identified in Scotland. Twelve cases were identified; nine primary cases, two secondary and one asymptomatic case. Extensive food history investigations identified venison products containing wild venison produced by a single food business operator as the most likely source of the outbreak. Of the nine primary cases, eight had consumed venison products, and one case had not eaten venison themselves but had handled and cooked raw venison in the household. This was the first reported outbreak of Shiga toxin-producing Escherichia coli (STEC) linked to venison products in the UK, and was also notable due to the implicated products being commercially produced and widely distributed. In contrast, previous venison outbreaks reported from other countries have tended to be smaller and related to individually prepared carcases. The outbreak has highlighted some important knowledge gaps in relation to STEC in venison that are currently been investigated via a number of research studies.
Molecular characterization of pediatric low-grade glioma (pLGG) over the last decade has identified recurrent alterations, most commonly involving BRAF, and less frequently other pathways including MYB and MYBL1. Many of these molecular markers have been exploited clinically to aid in diagnosis and treatment decisions. However, their frequency and prognostic significance remain unknown. Further, a significant portion of cases do not have any of these alterations and what underlies these cases remains unknown. To address this we compiled a cohort of 562 patients diagnosed at SickKids from 1990-2017. We identified molecular alterations in 454 cases (81% of the cohort). The most frequent events were those involving BRAF; either as fusions (most commonly with KIAA1549 (30%)) or V600E mutations (17%) and NF-1 (22%). Less frequently, we identified recurrent FGFR1 fusions and mutations (3%), MYB/MYBL alterations (2%), H3F3AK27M (2%) or IDH1R132H (0.5%) mutations, as well as other novel rare events. Survival analysis revealed significantly better progression-free survival (PFS) and overall survival (OS) of KIAA1549-BRAF fused patients compared to BRAFV600E with 10-year OS 97.7% (95%, CI 95.5-100) and 83.9% (95%, CI 72.5-95.6), respectively. In addition to survival, molecular alterations predicted differences in response to conventional therapeutics; BRAF fused patients showed a 46% response-rate, versus only 14% in V600E patients. pLGGs harboring H3F3AK27M progressed early with median PFS of 11 months. In patients with MYB/MYBL1, FGFR1/FGFR2 alterations, we observed only one death (FGFR1N546K case). The work here represents the largest cohort of pLGGs with molecular profiling and their impact on the clinical behaviour of the disease.
For livestock production systems to play a positive role in global food security, the balance between their benefits and disbenefits to society must be appropriately managed. Based on the evidence provided by field-scale randomised controlled trials around the world, this debate has traditionally centred on the concept of economic-environmental trade-offs, of which existence is theoretically assured when resource allocation is perfect on the farm. Recent research conducted on commercial farms indicates, however, that the economic-environmental nexus is not nearly as straightforward in the real world, with environmental performances of enterprises often positively correlated with their economic profitability. Using high-resolution primary data from the North Wyke Farm Platform, an intensively instrumented farm-scale ruminant research facility located in southwest United Kingdom, this paper proposes a novel, information-driven approach to carry out comprehensive assessments of economic-environmental trade-offs inherent within pasture-based cattle and sheep production systems. The results of a data-mining exercise suggest that a potentially systematic interaction exists between ‘soil health’, ecological surroundings and livestock grazing, whereby a higher level of soil organic carbon (SOC) stock is associated with a better animal performance and less nutrient losses into watercourses, and a higher stocking density with greater botanical diversity and elevated SOC. We contend that a combination of farming system-wide trials and environmental instrumentation provides an ideal setting for enrolling scientifically sound and biologically informative metrics for agricultural sustainability, through which agricultural producers could obtain guidance to manage soils, water, pasture and livestock in an economically and environmentally acceptable manner. Priority areas for future farm-scale research to ensure long-term sustainability are also discussed.
Phased Array Feed (PAF) technology is the next major advancement in radio astronomy in terms of combining high sensitivity and large field of view. The Focal L-band Array for the Green Bank Telescope (FLAG) is one of the most sensitive PAFs developed so far. It consists of 19 dual-polarization elements mounted on a prime focus dewar resulting in seven beams on the sky. Its unprecedented system temperature of ~17 K will lead to a 3 fold increase in pulsar survey speeds as compared to contemporary single pixel feeds. Early science observations were conducted in a recently concluded commissioning phase of the FLAG where we clearly demonstrated its science capabilities. We observed a selection of normal and millisecond pulsars and detected giant pulses from PSR B1937+21.
We present mid-IR (8–13μm) images of dust in seven proto-planetary nebulae (PPN), GL2343, HD 161796, 89 Her, OH 0739–1435, CRL2688, IRAS 22272+5435, and CRL618. The images were taken at UKIRT and the IRTF with the Berkeley mid-IR camera which was developed at the Space Sci. Lab. in UC Berkeley and is supported by IGPP and LEA, LLNL. The results presented here are part of an on-going mid-IR imaging project to study the morphological development of a star as it evolves from the Asymptotic Giant Branch (AGB) to the planetary nebula (PN) stage. In particular, we aim to establish when non-spherical symmetry which is evident in so many PN arises. Four of the objects are oxygen rich. Of these, GL2343 (Fig. 1) and HD 161796 are found to have spherical dust shells in the mid-IR with diameters of 6.″ 7 and 3″, respectively. OH 0739 is marginally resolved, but has a hint of elongation that is aligned with the bipolar nebula evident in the near-IR. 89 Her is unresolved at 1.″ 1 resolution. 89 Her, HD 161796 and GL2343, all high latitude supergiants, appear to form an evolutionary sequence as evidenced by the size of their circumstellar dust shells. Three of the objects are carbon rich. CRL2688 and IRAS 22272 +5435 are found to have elongated structures which suggest a bipolar morphology. CRL 618 is unresolved at 1.″ 7, but is known to be bipolar from optical studies. Hence, with the exception of OH 0739, a known binary, the oxygen rich PPN have spherical dust shells while the carbon rich have bipolar dust shells. Our small number of observations do not provide solid statistics; however, this trend suggests that nebula bipolarity is linked to carbon-rich chemistry.
We present mid-IR and far-IR images of a variety of AGB stars and red supergiants. The mid-IR images were all taken with the Berkeley/Livermore mid-IR array camera, which employs a 10 × 64 pixel Hughes photoconductor. All the images reported here were taken using a 10% bandpass CVF, at various wavelengths in the 10μm atmospheric window. These were supplemented by IRAS images, some constructed from survey scans, others made as Additional Observations during the pointed phase of the IRAS mission. We have so far observed 11 such sources with our mid-IR camera, and report here that only two of them (R Aql and V Hya) appear to be unresolved.
We present very high signal-to-noise observations of the (1,0) and (0,0) vibrational bands of interstellar CN near 3580 and 3874 Å toward HD 21483. Corrected for saturation with a derived b-value of 1.29±0.05 km s-1, these CN line strengths yield excitation temperatures of 2.83±0.09 and 2.76±0.07 K for the J=1-2 and J=0-1 rotational transitions at 1.32 and 2.64 mm. In the absence of local CN excitation, these values represent the brightness temperature of the cosmic microwave background (CMB) radiation at these wavelengths. Millimeter observations have revealed no CN emission at 2.64 mm toward HD 21483 and allow us to set a 2σ upper limit of 0.11 K on the contribution of local processes to the J=0-1 excitation. Considering this limit and the lesser likelihood of local J=1-2 excitation, our observations indicate a CMB temperature of 2.83±0.09 K at 1.32 mm.
Government transparency is widely promoted, yet little is known about transparency’s effects. Survey experiments reported here, made on the streets of Lima, Peru, investigate a simple question: what are the effects of government-sponsored transparency websites, and the information revealed by those efforts, on attitudes about the Peruvian political system? Like many developing countries, Peru lacks much system support, making it more difficult to improve governance and democracy; transparency itself has little impact on political attitudes. However, some dimensions of the information provided by transparency matter: endorsement by a credible third party or framing that associates comparatively good community well-being with government performance. These conditions substantively increase Peruvians’ approval of the national political community, the regime’s performance, institutions, and local government.
This study examines the interplay between individual and social–developmental factors in the development of positive functioning, substance use problems, and mental health problems. This interplay is nested within positive and negative developmental cascades that span childhood, adolescence, the transition to adulthood, and adulthood. Data are drawn from the Seattle Social Development Project, a gender-balanced, ethnically diverse community sample of 808 participants interviewed 12 times from ages 10 to 33. Path modeling showed short- and long-term cascading effects of positive social environments, family history of depression, and substance-using social environments throughout development. Positive family social environments set a template for future partner social environment interaction and had positive influences on proximal individual functioning, both in the next developmental period and long term. Family history of depression adversely affected mental health functioning throughout adulthood. Family substance use began a cascade of substance-specific social environments across development, which was the pathway through which increasing severity of substance use problems flowed. The model also indicated that adolescent, but not adult, individual functioning influenced selection into positive social environments, and significant cross-domain effects were found in which substance-using social environments affected subsequent mental health.
Although the HST GSC–I (Paper-I: Lasker et al. 1990, Paper-II: Russell et al. 1990, Paper-III: Jenkner et al. 1990) has been used with great success operationally, it was always known that it was possible to improve the scientific and operational usefulness by an increase in scope to include multi-color and multi-epoch data. Once the GSC-II concept was established, it was evident that, even beyond the original motivations in HST operations, it would address a number of other astronomical needs such as increasing demands for fainter catalogues to support remote or queue scheduling capabilities and adaptive optics on the next generation of large-aperture, new-technology telescopes. In addition, the all sky nature of the GSC–II makes it a natural data source for research in galactic structure.
We present UBVRI photometry of the faint and highly erratic cataclysmic variable discovered by Hawkins (1983) from a sequence of U.K. Schmidt plates. Observations using the ANU 2.3 m telescope over two nights in September 1986 show pronounced and repeatable modulation at a binary period of 108.6 min. Dramatic colour differences are evident in the folded UBVRI light curves: in the U band, a single sinusoidal peak is present, while at longer wavelengths, a second red peak dominates at a phase separation of Δϕ = 0.5. This behaviour is strongly suggestive of cyclotron emission from two magnetic accretion funnels in an AM Herculis binary system. Furthermore, the binary period lies in the narrow range of 100-115 minutes that characterizes most of the AM Herculis variables lying on the short side of the 2-3 hour period gap. We conclude therefore that the object is almost certainly a new AM Herculis system, and develop a model in which the blue and red components originate from two non-diametrically opposed cyclotron regions that are characterized by differing electron temperatures and opacities. Predictions are made regarding the linear and circular polarization properties of this important new magnetic variable.
We have undertaken a study of the 3-D spatial distribution of the older (τ ≥ 1–2 Gyr) stellar population lying beyond ~ 2 kpc in projected radial distance from the centre of the SMC. The study will eventually cover 120 square degrees including six overlapping Schmidt fields. Here we present the results from an area of 80 square degrees including the western, northern and north-eastern outer parts of the SMC.
This chapter reviews the current knowledge of the molecular mechanisms controlling embryonic lung development in animal models from the initial specification of a small number of respiratory progenitor cells in the ventral foregut endoderm through the formation of the mature adult lung with regionally specialized epithelial, interstitial, and vascular compartments. In the second half of this chapter we introduce induced pluripotent stem cells (iPSCs) as a compelling new platform to study human lung biology at developmental time-points previously inaccessible to researchers. iPSCs offer the potential to generate functional lung tissue in vitro by translating the knowledge gained from studying respiratory system development in different animal models where many of the signaling pathways or airway branching mechanisms are evolutionarily conserved. There are many exciting possible applications of iPSC-derived lung tissue, including the ability to model human lung disease, screen novel drug therapies, and ultimately generate functional, transplantable lung cells or 3-D tissues for those suffering from one of the many forms of end-stage lung disease.
Digital stacking of Schmidt Plates greatly increases the depth of the data allowing detection of galaxies at ∼ 1. We can probe the angular correlations of galaxy and cluster positions over scales of ∼ 500h−1 Mpc. Radial distance information can be obtained by identifying radio galaxies in the field and using their “standard candle” properties. A search for cosmic string effects, beginning with the stacked dataset, has now been extended to ∼ 100 equatorial J-plates.