317 research outputs found

    Modern seawater acidification: The response of foraminifera to high-CO<inf>2</inf> conditions in the Mediterranean Sea

    Get PDF
    The seas around the island of Ischia (Italy) have a lowered pH as a result of volcanic gas vents that emit carbon dioxide from the sea floor at ambient seawater temperatures. These areas of acidified seawater provide natural laboratories in which to study the long-term biological response to rising CO2 levels. Benthic foraminifera (single-celled protists) are particularly interesting as they have short life histories, are environmentally sensitive and have an excellent fossil record. Here, we examine changes in foraminiferal assemblages along pH gradients at CO2 vents on the coast of Ischia and show that the foraminiferal distribution, diversity and nature of the fauna change markedly in the living assemblages as pH decreases. © 2010 Geological Society of London

    Come back Marshall, all is forgiven? : Complexity, evolution, mathematics and Marshallian exceptionalism

    Get PDF
    Marshall was the great synthesiser of neoclassical economics. Yet with his qualified assumption of self-interest, his emphasis on variation in economic evolution and his cautious attitude to the use of mathematics, Marshall differs fundamentally from other leading neoclassical contemporaries. Metaphors inspire more specific analogies and ontological assumptions, and Marshall used the guiding metaphor of Spencerian evolution. But unfortunately, the further development of a Marshallian evolutionary approach was undermined in part by theoretical problems within Spencer's theory. Yet some things can be salvaged from the Marshallian evolutionary vision. They may even be placed in a more viable Darwinian framework.Peer reviewedFinal Accepted Versio

    Clinical, angiographic and procedural correlates of quantitative coronary dimensions after directional coronary atherectomy

    Get PDF
    AbstractTo define the clinical, angiographic and procedural correlates of quantitative coronary dimensions after directional coronary atherectomy, 400 lesions in 378 patients were analyzed with use of qualitative morphologic and quantitative angiographic methods. Successful atherectomy, defined by a <75% residual area stenosis, tissue retrieval and the absence of in-hospital ischemic complications, was performed in 351 lesions (87.7%). After atherectomy, minimal cross-sectional area increased from 1.2 ± 1.1 to 6.6 ± 4.4 mm2(p < 0.001) and percent area stenosis was reduced from 87 ± 10% to 31 ± 42% (p < 0.001).By univariate analysis, device size (p < 0.001) and left circumflex artery lesion location (p = 0.004) were associated with a larger final minimal cross-sectional area. Conversely, restenotic lesion (p = 0.002), lesion length ≄ 10 mm (p = 0.018) and lesion calcification (p = 0.035) were quantitatively associated with a smaller final minimum cross-sectional area. With use of stepwise multivariate analysis to control for the reference area, atherectomy device size (p = 0.003) and left circumflex lesion location (p = 0.007) were independently associated with a larger final minimal cross-sectional area, whereas restenotic lesion (p = 0.010), diffuse proximal disease (p = 0.033), lesion length ≄ 10 mm (p = 0.026) and lesion calcification (p = 0.081) were significantly correlated with a smaller final minimal cross-sectional area. The number of specimens excised, the number of atherectomy passes and atherectomy balloon inflation pressure did not correlate with the final minimal cross-sectional area.Thus, directional atherectomy results in marked improvement of coronary lumen dimensions, at least in part correlated with the presence of certain clinical, angiographic and procedural factors at the time of atherectomy

    Fingerstick test quantifying humoral and cellular biomarkers indicative for M-leprae infection

    Get PDF
    Objectives: New user-friendly diagnostic tests for detection of individuals infected by Mycobacterium leprae (M. leprae), the causative pathogen of leprosy, can help guide therapeutic and prophylactic treatment, thus positively contributing to clinical outcome and reduction of transmission. To facilitate point-of-care testing without the presence of phlebotomists, the use of fingerstick blood (FSB) rather than whole blood-derived serum is preferred. This study is a first proof-of-principle validating that previously described rapid serum tests detecting antibodies and cytokines can also be used with FSB. Methods: Quantitative detection of previously identified biomarkers for leprosy and M. leprae infection, anti-M. leprae PGL-I IgM antibodies (αPGL-I), IP-10 and CRP, was performed with lateral flow (LF) strips utilizing luminescent up-converting reporter particles (UCP) and a portable reader generating unbiased read-outs. Precise amounts of FSB samples were collected using disposable heparinized capillaries. Biomarker levels in paired FSB and serum samples were determined using UCP-LF test strips for leprosy patients and controls in Bangladesh, Brazil, South-Africa and the Netherlands. Results: Correlations between serum and FSB from the same individuals for αPGL-I, CRP and IP-10 were highly significant (p < .0001) even after FSB samples had been frozen. The αPGL-I FSB test was able to correctly identify all multibacillary leprosy patients presenting a good quantitative correlation with the bacterial index. Conclusions: Reader-assisted, quantitative UCP-LF tests for the detection of humoral and cellular biomarkers for M. leprae infection, are compatible with FSB. This allows near-patient testing for M. leprae infection and immunomonitoring of treatment without highly trained staff. On site availability of test-result concedes immediate initiation of appropriate counselling and treatment. Alternatively, the UCP-LF format allows frozen storage of FSB samples compatible with deferred testing in central laboratories

    Study of the B^0 Semileptonic Decay Spectrum at the Upsilon(4S) Resonance

    Full text link
    We have made a first measurement of the lepton momentum spectrum in a sample of events enriched in neutral B's through a partial reconstruction of B0 --> D*- l+ nu. This spectrum, measured with 2.38 fb**-1 of data collected at the Upsilon(4S) resonance by the CLEO II detector, is compared directly to the inclusive lepton spectrum from all Upsilon(4S) events in the same data set. These two spectra are consistent with having the same shape above 1.5 GeV/c. From the two spectra and two other CLEO measurements, we obtain the B0 and B+ semileptonic branching fractions, b0 and b+, their ratio, and the production ratio f+-/f00 of B+ and B0 pairs at the Upsilon(4S). We report b+/b0=0.950 (+0.117-0.080) +- 0.091, b0 = (10.78 +- 0.60 +- 0.69)%, and b+ = (10.25 +- 0.57 +- 0.65)%. b+/b0 is equivalent to the ratio of charged to neutral B lifetimes, tau+/tau0.Comment: 14 page, postscript file also available at http://w4.lns.cornell.edu/public/CLN

    Radiative Decay Modes of the D0D^{0} Meson

    Get PDF
    Using data recorded by the CLEO-II detector at CESR we have searched for four radiative decay modes of the D0D^0 meson: D0â†’Ï•ÎłD^0\to\phi\gamma, D0â†’Ï‰ÎłD^0\to\omega\gamma, D0→Kˉ∗γD^0\to\bar{K}^{*}\gamma, and D0→ρ0ÎłD^0\to\rho^0\gamma. We obtain 90% CL upper limits on the branching ratios of these modes of 1.9×10−41.9\times 10^{-4}, 2.4×10−42.4\times 10^{-4}, 7.6×10−47.6\times 10^{-4} and 2.4×10−42.4\times 10^{-4} respectively.Comment: 15 page postscript file, postscript file also available through http://w4.lns.cornell.edu/public/CLN
    • 

    corecore