2,295 research outputs found

    Effects of ocean acidification on invertebrate settlement at volcanic CO<inf>2</inf> vents

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    We present the first study of the effects of ocean acidification on settlement of benthic invertebrates and microfauna. Artificial collectors were placed for 1 month along pH gradients at CO2 vents off Ischia (Tyrrhenian Sea, Italy). Seventy-nine taxa were identified from six main taxonomic groups (foraminiferans, nematodes, polychaetes, molluscs, crustaceans and chaetognaths). Calcareous foraminiferans, serpulid polychaetes, gastropods and bivalves showed highly significant reductions in recruitment to the collectors as pCO2 rose from normal (336-341 ppm, pH 8.09-8.15) to high levels (886-5,148 ppm) causing acidified conditions near the vents (pH 7.08-7.79). Only the syllid polychaete Syllis prolifera had higher abundances at the most acidified station, although a wide range of polychaetes and small crustaceans was able to settle and survive under these conditions. A few taxa (Amphiglena mediterranea, Leptochelia dubia, Caprella acanthifera) were particularly abundant at stations acidified by intermediate amounts of CO2 (pH 7. 41-7.99). These results show that increased levels of CO2 can profoundly affect the settlement of a wide range of benthic organisms. © 2010 Springer-Verlag

    Shape Transition in the Epitaxial Growth of Gold Silicide in Au Thin Films on Si(111)

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    Growth of epitaxial gold silicide islands on bromine-passivated Si(111) substrates has been studied by optical and electron microscopy, electron probe micro analysis and helium ion backscattering. The islands grow in the shape of equilateral triangles up to a critical size beyond which the symmetry of the structure is broken, resulting in a shape transition from triangle to trapezoid. The island edges are aligned along Si[110]Si[110] directions. We have observed elongated islands with aspect ratios as large as 8:1. These islands, instead of growing along three equivalent [110] directions on the Si(111) substrate, grow only along one preferential direction. This has been attributed to the vicinality of the substrate surface.Comment: revtex version 3.0, 11 pages 4 figures available on request from [email protected] - IP/BBSR/93-6

    Coastal saltmarsh managed realignment drives rapid breach inlet and external creek evolution, Freiston Shore (UK)

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    The creation of saltmarsh through the managed realignment of sea defences, implemented in NW Europe as a sustainable coastal defence option, represents a substantial hydrodynamic perturbation to the local coastal system. The impact of a significantly increased tidal prism on hydromorphological features was investigated at Freiston Shore, Lincolnshire UK. Local tidal conditions and inadequate drainage at this realignment trial contributed to significant channel erosion due to the establishment of water surface slopes and pooling between the newly realigned site and the adjacent intertidal zone. Very high spatial resolution aerial photography and blimp photography were used to monitor inlet evolution from breaching in August 2002 to March 2008, showing a highly non-linear response with breach channels increasing in width by up to 960% within 2.5. months. Airborne laser scanning/LiDAR and terrestrial laser scanning quantified breach channel volume increases, showing a similar pattern. Breach channel evolution did not follow established tidal prism-channel width/cross-sectional area relationships that are often used to guide realignment design. Pre- and post-breach rates of external creek morphology change between 1999 and 2006 were also quantified, with intertidal creeks attached to the breach channels increasing significantly after realignment in both width and depth. This study highlights the physical processes affected by managed realignment, and the importance of understanding the causes of complex water surface slopes at multiple scales. © 2013 Elsevier B.V

    A phase I pharmacokinetics trial comparing PF-05280586 (a potential biosimilar) and rituximab in patients with active rheumatoid arthritis

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    Aims: Pharmacokinetic (PK) similarity was assessed among PF‐05280586 (a proposed biosimilar) vs. rituximab sourced from the European Union (rituximab‐EU) and the United States (rituximab‐US). Pharmacodynamics (PD), overall safety and immunogenicity were also evaluated. Methods: Patients with active rheumatoid arthritis on a background of methotrexate and inadequate response to one or more tumour necrosis factor antagonist therapies were randomized to intravenous PF‐05280586, rituximab‐EU or rituximab‐US 1000 mg doses on study days 1 and 15. Results: A total of 220 patients were randomized to receive study treatment as assigned. Of these, 198 met per‐protocol population criteria for inclusion in the PK data analysis. PF‐05280586, rituximab‐EU and rituximab‐US exhibited similar PK profiles following administration of assigned study drug on days 1 and 15. The 90% confidence intervals of test‐to‐reference ratios for Cmax, AUCT, AUC0–∞ and AUC2‐week were within the bioequivalence margin of 80.00–125.00% for comparisons of PF‐05280586 with rituximab‐EU, PF‐05280586 with rituximab‐US, and rituximab‐EU with rituximab‐US. All treatments resulted in a rapid and profound reduction in CD19+ B cells and sustained profound B cell suppression up to week 25. The incidence of antidrug antibody (ADA) response (n = 7, 10 and 9 for PF‐05280586, rituximab‐EU and rituximab‐US, respectively), time to ADA emergence and ADA titres were similar across treatments. None of the ADA‐positive samples was positive for neutralizing activity. No clinically meaningful differences in adverse events were identified. Conclusions: The study demonstrated PK similarity among PF‐05280586, rituximab‐EU and rituximab‐US. In addition, all treatments showed comparable CD19+ B cell depletion PD responses, as well as safety and immunogenicity profiles

    Worker well-being and the importance of work: bridging the gap

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    The importance of worker well-being is widely-embraced both in theory and policy, but there are numerous perspectives on what it is, how to measure it, whether it needs improving and if so, how to improve it. We argue that a more complete approach to worker well-being needs to consider workers as full citizens who derive and experience both public and private benefits and costs from working. A broad framework on the meanings of work is used to expand the boundaries of worker well-being to reflect the broad importance of work in human life

    Measurement of the polarization parameter in π−p\pi^{-}p backward elastic scattering at 6 GeV/c

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    The polarization parameter in pi /sup -/p elastic scattering has been measured in the backward angular region at an incident momentum of 6 GeV/c. The measurements cover the range of four momentum transfer u=0 to -1(GeV/c)/sup 2/, and were obtained with a high intensity pion beam, a butanol polarized proton target, and arrays of scintillation counter hodoscopes. The polarization is different from zero, in contradiction to the prediction of the naive one trajectory Regge- exchange model. It increases positively with the four-momentum transfer u, reaching a maximum of about 0.4 at u approximately=-0.3(Ge V/c)/sup 2/. It then decreases and becomes slightly negative beyond u approximately=-0.5(GeV/c)/sup 2/. A variety of baryon exchange models are briefly reviewed and none are found to be in complete agreement with all the experimental data

    Conducting longitudinal research with older widows : Exploring personal communities through multiple methods

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    This article reports on the process of undertaking a longitudinal multiple methods study with older women experiencing the transition of later life widowhood. A series of three qualitative in depth interviews were conducted with twenty-six older widows in North Staffordshire, United Kingdom. Interviews included the use of personal community diagrams to identify the structure of personal communities, and Christmas and Christmas cards to further explore social relationships and practices during transition. Examples of cases are given to illustrate the findings derived from the methods employed. The cases demonstrate the diverse and often paradoxical nature of social relationships within similar networks

    Dwelling in Strangeness: accounts of the Kingsley Hall Community, London (1965-1970)

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    This article explores archival accounts of the experimental community, Kingsley Hall (1965-70), established by R. D. Laing, the radical Scottish psychiatrist. The paper contributes to renewed interest in Kingsley Hall, R. D. Laing's radical psychiatry and UK counterculture. Archival sources enable not only the further exploration of already known figures but also let us hear previously unheard voices. Following a discussion of archival materials, the Hall is analyzed thematically and historically as (i) an inner spaceship; (ii) an embattled middle-class countercultural plantation; (iii) a site of spiritual renewal and development; (iv) a single-building arts colony; and (v) a countercultural experiment. Finally, it is argued that with re-evaluation of 1960s and 1970s counterculture now underway on the Left, the Hall’s experiment in Laingian countercultural psychiatry—as we may fittingly call it—may yet inform future radical projects (in mental health and beyond)

    Effects of Fasting on Isolated Murine Skeletal Muscle Contractile Function During Acute Hypoxia

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    Stored muscle carbohydrate supply and energetic efficiency constrain muscle functional capacity during exercise and are influenced by common physiological variables (e.g. age, diet, and physical activity level). Whether these constraints affect overall functional capacity or the timing of muscle energetic failure during acute hypoxia is not known. We interrogated skeletal muscle contractile properties in two anatomically distinct rodent hindlimb muscles that have well characterized differences in energetic efficiency (locomotory- extensor digitorum longus (EDL) and postural- soleus muscles) following a 24 hour fasting period that resulted in substantially reduced muscle carbohydrate supply. 180 mins of acute hypoxia resulted in complete energetic failure in all muscles tested, indicated by: loss of force production, substantial reductions in total adenosine nucleotide pool intermediates, and increased adenosine nucleotide degradation product-inosine monophosphate (IMP). These changes occurred in the absence of apparent myofiber structural damage assessed histologically by both transverse section and whole mount. Fasting and the associated reduction of the available intracellular carbohydrate pool (~50% decrease in skeletal muscle) did not significantly alter the timing to muscle functional impairment or affect the overall force/work capacities of either muscle type. Fasting resulted in greater passive tension development in both muscle types, which may have implications for the design of pre-clinical studies involving optimal timing of reperfusion or administration of precision therapeutics
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