28 research outputs found

    Direct Identification of the Glass Transition: Growing Length Scale and the Onset of Plasticity

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    Understanding the mechanical properties of glasses remains elusive since the glass transition itself is not fully understood, even in well studied examples of glass formers in two dimensions. In this context we demonstrate here: (i) a direct evidence for a diverging length scale at the glass transition (ii) an identification of the glass transition with the disappearance of fluid-like regions and (iii) the appearance in the glass state of fluid-like regions when mechanical strain is applied. These fluid-like regions are associated with the onset of plasticity in the amorphous solid. The relaxation times which diverge upon the approach to the glass transition are related quantitatively.Comment: 5 pages, 5 figs.; 2 figs. omitted, new fig., quasi-crystal discussion omitted, new material on relaxation time

    Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease

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    Background: Experimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. Methods: We conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1β, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. RESULTS: At 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in the 300-mg group than in the placebo group. Canakinumab did not reduce lipid levels from baseline. At a median follow-up of 3.7 years, the incidence rate for the primary end point was 4.50 events per 100 person-years in the placebo group, 4.11 events per 100 person-years in the 50-mg group, 3.86 events per 100 person-years in the 150-mg group, and 3.90 events per 100 person-years in the 300-mg group. The hazard ratios as compared with placebo were as follows: in the 50-mg group, 0.93 (95% confidence interval [CI], 0.80 to 1.07; P = 0.30); in the 150-mg group, 0.85 (95% CI, 0.74 to 0.98; P = 0.021); and in the 300-mg group, 0.86 (95% CI, 0.75 to 0.99; P = 0.031). The 150-mg dose, but not the other doses, met the prespecified multiplicity-adjusted threshold for statistical significance for the primary end point and the secondary end point that additionally included hospitalization for unstable angina that led to urgent revascularization (hazard ratio vs. placebo, 0.83; 95% CI, 0.73 to 0.95; P = 0.005). Canakinumab was associated with a higher incidence of fatal infection than was placebo. There was no significant difference in all-cause mortality (hazard ratio for all canakinumab doses vs. placebo, 0.94; 95% CI, 0.83 to 1.06; P = 0.31). Conclusions: Antiinflammatory therapy targeting the interleukin-1β innate immunity pathway with canakinumab at a dose of 150 mg every 3 months led to a significantly lower rate of recurrent cardiovascular events than placebo, independent of lipid-level lowering. (Funded by Novartis; CANTOS ClinicalTrials.gov number, NCT01327846.

    On the transverse magnetization of the anisotropic superconductor 2H-NbSe2

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    Torque measurements were performed on a high-quality single crystal of the uniaxial superconductor 2H-NbSe2 in a tilted magnetic field 0-200 kG, in the temperature range 1.5-4.2 K. The transverse component of the absolute magnetization was derived in a magnetic field directed at an angle of 77degrees to the axis of anisotropy, and its field dependence was analyzed in a reversible domain of the mixed state. The penetration depth and anisotropy characteristics were obtained for the sample under study. (C) 2002 American Institute of Physics

    Magura Cave, Bulgaria: A multidisciplinary study of Late Pleistocene human palaeoenvironment in the Balkans

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    Two trenches excavated at Magura Cave, north-west Bulgaria, have provided Late Pleistocene lithic artefacts as well as environmental evidence in the form of large and small mammals, herpetofauna and pollen recovered from Crocuta coprolites. One of the trenches also has a visible tephra layer which has been confirmed as representing the major Campanian Ignimbrite eruption and is accurately dated at the source area to 39,280 ± 55 yrs and radiocarbon determinations have added to chronological resolution at the site. The palaeoenvironment of the region during the Late Pleistocene is discussed in the context of hominin presence and shows a mosaic landscape in a region considered a crucial refugium for both plants and mammals, including hominins.status: publishe

    X-ray study of Nd₀.₅Sr₀.₅MnO₃ above and below the ferromagnetic metal-antiferromagnetic insulator spontaneous phase transition manganite structure

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    The crystal structure of the manganite Nd₀.₅Sr₀.₅MnO₃ is studied at temperatures T=300 and 77.3 K by means of an x-ray diffractometer. It is shown that the transition from the ferromagnetic metallic state to the antiferromagnetic insulating charge-ordered state is accompanied by a lowering of the symmetry of the structure from orthorhombic to monoclinic. The space-group symmetry of the orthorhombic and monoclinic phases is identified as Imma and P21 / m, respectively. Twinning of the crystal and the formation of a twin domain structure with coherent boundaries in the (00l) crystallographic planes are found
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