35 research outputs found

    Rotation-induced 3D vorticity in 4He superfluid films adsorbed on a porous glass

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    Detailed study of torsional oscillator experiments under steady rotation up to 6.28 rad/sec is reported for a 4He superfluid monolayer film formed in 1 micrometer-pore diameter porous glass. We found a new dissipation peak with the height being in proportion to the rotation speed, which is located to the lower temperature than the vortex pair unbinding peak observed in the static state. We propose that 3D coreless vortices ("pore vortices") appear under rotation to explain this new peak. That is, the new peak originates from dissipation close to the pore vortex lines, where large superfluid velocity shifts the vortex pair unbinding dissipation to lower temperature. This explanation is confirmed by observation of nonlinear effects at high oscillation amplitudes.Comment: 4pages, 5figure

    Varespladib and cardiovascular events in patients with an acute coronary syndrome: the VISTA-16 randomized clinical trial

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    IMPORTANCE: Secretory phospholipase A2(sPLA2) generates bioactive phospholipid products implicated in atherosclerosis. The sPLA2inhibitor varespladib has favorable effects on lipid and inflammatory markers; however, its effect on cardiovascular outcomes is unknown. OBJECTIVE: To determine the effects of sPLA2inhibition with varespladib on cardiovascular outcomes. DESIGN, SETTING, AND PARTICIPANTS: A double-blind, randomized, multicenter trial at 362 academic and community hospitals in Europe, Australia, New Zealand, India, and North America of 5145 patients randomized within 96 hours of presentation of an acute coronary syndrome (ACS) to either varespladib (n = 2572) or placebo (n = 2573) with enrollment between June 1, 2010, and March 7, 2012 (study termination on March 9, 2012). INTERVENTIONS: Participants were randomized to receive varespladib (500 mg) or placebo daily for 16 weeks, in addition to atorvastatin and other established therapies. MAIN OUTCOMES AND MEASURES: The primary efficacy measurewas a composite of cardiovascular mortality, nonfatal myocardial infarction (MI), nonfatal stroke, or unstable angina with evidence of ischemia requiring hospitalization at 16 weeks. Six-month survival status was also evaluated. RESULTS: At a prespecified interim analysis, including 212 primary end point events, the independent data and safety monitoring board recommended termination of the trial for futility and possible harm. The primary end point occurred in 136 patients (6.1%) treated with varespladib compared with 109 patients (5.1%) treated with placebo (hazard ratio [HR], 1.25; 95%CI, 0.97-1.61; log-rank P = .08). Varespladib was associated with a greater risk of MI (78 [3.4%] vs 47 [2.2%]; HR, 1.66; 95%CI, 1.16-2.39; log-rank P = .005). The composite secondary end point of cardiovascular mortality, MI, and stroke was observed in 107 patients (4.6%) in the varespladib group and 79 patients (3.8%) in the placebo group (HR, 1.36; 95% CI, 1.02-1.82; P = .04). CONCLUSIONS AND RELEVANCE: In patients with recent ACS, varespladib did not reduce the risk of recurrent cardiovascular events and significantly increased the risk of MI. The sPLA2inhibition with varespladib may be harmful and is not a useful strategy to reduce adverse cardiovascular outcomes after ACS. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01130246. Copyright 2014 American Medical Association. All rights reserved

    Study of QGP signatures with the phi->K+K- signal in Pb-Pb ALICE events

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    The phi->K+K- decay channel in Pb-Pb collisions at LHC is studied through a full simulation of the ALICE detector. The study focuses on possible signatures in this channel of quark-gluon plasma (QGP) formation. On a basis of 10^6 collisions at high centrality some proposed QGP signatures are clearly visible both in K+K- invariant mass and transverse mass distributions. The high significance of this observation appears to reside heavily on the use of the TOF (Time Of Flight) system of ALICE in addition to its central tracking detectors.Comment: 9 pages, 7 figures, to appear in EPJ

    Patients with a Combination of Atrial Fibrillation and Chronic Heart Failure in Clinical Practice: Comorbidities, Drug Treatment and Outcomes

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    Aim. To assess in clinical practice the structure of multimorbidity, cardiovascular pharmacotherapy and outcomes in patients with a combination of atrial fibrillation (AF) and chronic heart failure (CHF) based on prospective registries of patients with cardiovascular diseases (CVD).Materials and Methods. The data of 3795 patients with atrial fibrillation (AF) were analyzed within the registries RECVASA (Ryazan), RECVASA FP (Moscow, Kursk, Tula, Yaroslavl), REGION-PO and REGION-LD (Ryazan), REGION-Moscow, REGATA (Ryazan). The comparison groups consisted of 3016 (79.5%) patients with AF in combination with CHF and 779 (29.5%) patients with AF without CHF. The duration of prospective observation is from 2 to 6 years.Results. Patients with a combination of AF and CHF (n=3016, age was 72.0±10.3 years; 41.8% of men) compared with patients with AF without CHF (n=779, age was 70.3±12.0 years; 43.5% of men) had a higher risk of thromboembolic complications (CHA2DS2-VASc – 4.68±1.59 and 3.10±1.50; p<0.001) and hemorrhagic complications (HAS-BLED – 1.59±0.77 and 1.33±0.76; p<0.05). Patients with a combination of AF and CHF significantly more often (p<0.001) than in the absence of CHF were diagnosed with arterial hypertension (93.9% and 83.8%), coronary heart disease (87.9% and 53,5%), myocardial infarction (28.4% and 14.0%), diabetes mellitus (22.4% and 7.7%), chronic kidney disease (24.8% and 16.2%), as well as respiratory diseases (20.1% and 15.3%; p=0.002). Patients with AF in the presence of CHF, compared with patients without CHF, were more often diagnosed with a permanent form of arrhythmia (49.3% and 32.9%; p<0.001) and less often paroxysmal (22.5% and 46.2%; p<0.001) form  of  arrhythmia.  Ejection  fraction  ≤40%  (9.3%  and  1.2%;  p<0.001),  heart  rate  ≥90/min  (23.7% and 19.3%; p=0.008) and blood pressure ≥140/90 mm Hg (59.9% and 52.2%; p<0.001) were recorded with AF in the presence of CHF more often than in the absence of CHF. The frequency of proper cardiovascular pharmacotherapy was higher, albeit insufficient, in the presence of CHF (64.9%) than in the absence of it (56.1%), but anticoagulants were prescribed less frequently when AF and CHF were combined (38.8% and  49, 0%; p<0.001). The frequency of unreasonable prescription of antiplatelet agents instead of anticoagulants was 52.5% and 33.3% (p<0.001) in the combination of AF, CHF and coronary heart disease, as well as in the combination of AF with coronary heart disease but without CHF. Patients with AF and CHF during the observation period compared with those without CHF had higher mortality from all causes (37.6% and 30.3%; p=0.001), the frequency of non-fatal cerebral stroke (8.2% and 5.4%; p=0.032) and myocardial infarction (4.7% and 2.5%; p=0.036), hospitalizations for CVD (22.8% and 15.5%; p<0.001).Conclusion. Patients with a combination of AF and CHF, compared with the group of patients with AF without CHF, were older, had a higher risk of thromboembolic and hemorrhagic complications, they were more often diagnosed with other concomitant cardiovascular and chronic noncardiac diseases, decreased left ventricular ejection fraction, tachysystole, failure to achieve the target blood pressure level in the presence of arterial hypertension. The frequency of prescribing proper cardiovascular pharmacotherapy was higher, albeit insufficient, in the presence of CHF, while the frequency of prescribing anticoagulants was less. The  incidence of mortality from all causes, the development of non-fatal myocardial infarction   and cerebral stroke, as well as the incidence of hospitalizations for CVDs were higher in AF associated with CHF

    Combination of Atrial Fibrillation and Coronary Heart Disease in Patients in Clinical Practice: Comorbidities, Pharmacotherapy and Outcomes (Data from the REСVASA Registries)

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    Aim. Assess the structure of comorbid conditions, cardiovascular pharmacotherapy and outcomes in patients with atrial fibrillation (AF) and concomitant coronary artery disease (CAD) included in the outpatient and hospital RECVASA registries.Materials and methods. 3169 patients with AF were enrolled in outpatient RECVASA (Ryazan), RECVASA AF-Yaroslavl registries and hospital RECVASA AF (Moscow, Kursk, Tula). 2497 (78.8%) registries of patients with AF had CAD and 703 (28.2%) of them had a previous myocardial infarction (MI).Results. There were 2,497 patients with a combination of AF and CAD (age was 72.2±9.9 years; 43.1% of men; CHA2DS2-VASc – 4.57±1.61 points; HAS-BLED – 1.60±0,75 points), and the group with AF without CAD included 672 patients (age was 66.0±12.3 years; 43.2% of men; CHA2DS2-VASc – 3.26±1.67 points; HAS-BLED – 1,11±0.74 points). Patients with CAD were on average 6.2 years older and had a higher risk of thromboembolic and hemorrhagic complications (p<0.05). 703 patients with a combination of AF and CAD had the previous myocardial infarction (MI; age was 72.3±9.5 years; 55.2% of men; CHA2DS2-VASc – 4.57±1.61; HAS-BLED – 1.65±0.76), and 1794 patients didn't have previous MI (age was 72.2±10.0 years; 38.4% of men; CHA2DS2-VASc – 4.30±1.50; HAS-BLED – 1.58±0.78). The proportion of men was 1.4 times higher among those with the previous MI. Patients with a combination of AF and CAD significantly more often (p <0.0001) than in the absence of CAD received a diagnosis of hypertension (93.8% and 78.6%), chronic heart failure (90.1% and 51.2%), diabetes mellitus (21.4% and 13.8%), chronic kidney disease (24.8% and 17.7%), as well as anemia (7.0% and 3.0%; p=0.001). Patients with and without the previous MI had the only significant difference in the form of a diabetes mellitus higher incidence having the previous MI (27% versus 19.2%, p=0.0008). The frequency of proper cardiovascular pharmacotherapy was insufficient, mainly in the presence of CAD (67.8%) than in its absence (74.5%), especially the prescription of anticoagulants (39.1% and 66.2%; p <0.0001), as well as in the presence of the previous MI (63.3%) than in its absence (74.3%). The presence of CAD and, in particular, the previous MI, was significantly associated with a higher risk of death (risk ratio [RR]=1.58; 95% confidence interval [CI] was 1.33-1.88; p <0.001 and RR=1.59; 95% CI was 1.33-1.90; p <0.001), as well as with a higher risk of developing a combined cardiovascular endpoint (RR=1.88; 95% CI was 1.17-3 , 00; p <0.001 and RR=1.75; 95% CI was 1.44-2.12; p<0.001, respectively).Conclusion. 78.8% of patients from AF registries in 5 regions of Russia were diagnosed with CAD, of which 28.2% had previously suffered myocardial infarction. Patients with a combination of AF and CAD more often than in the absence of CAD had hypertension, chronic heart failure, diabetes, chronic kidney disease and anemia. Patients with the previous MI had higher incidence of diabetes than those without the previous MI. The frequency of proper cardiovascular pharmacotherapy was insufficient, and to a greater extent in the presence of CAD and the previous MI than in their absence. All-cause mortality was recorded in patients with a combination of AF and CAD more often than in the absence of CAD. All-cause mortality and the incidence of nonfatal myocardial infarction were higher in patients with AF and the previous MI than in those without the previous MI. The presence of CAD and, in particular, the previous MI, was significantly associated with a higher risk of death, as well as a higher risk of developing a combined cardiovascular endpoint

    Do fecundity-time models really predict extreme optimal egg sizes?

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    In 1973, Vance published a mathematical model that explains differences in reproductive strategies such as planktotrophy and lecithotrophy found in marine invertebrates. The original model Vance (The American Naturalist, 107, 339–352) traded fecundity against development time and resulted in a U-shaped fitness function suggesting that only extreme levels of egg provisioning (referred to as egg size) are evolutionarily stable. Several later models independently predicted evolutionary stability of extreme egg sizes, and this has been commonly interpreted as a proof that the Vance model, albeit oversimplified, reflects the fundamental evolutionary principle of disruptive egg size evolution in marine invertebrates. However, empirical studies of the last several decades have illustrated that intermediate levels of egg provisioning are commonly observed in nature. As a result, the recent modifications of the original Vance model have attempted to explain evolution of such intermediate strategies. Here we re-examine the earlier fecundity-time models of the ‘Vance family’ and show that only Vance and its minor modification by Grant (The American Naturalist, 122, 549–555) invariably predict evolutionary stability of extreme egg sizes. Most modifications of the original Vance model in fact can predict at least some intermediate optimal egg sizes and reproductive strategies. There is no reason to assume that selection towards extreme egg sizes is the driving force in the evolution of marine invertebrate life histories.14 page(s

    Determination of the shear strength of the metal-plastic adhesion bond and its response to lubrication

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    Role of Trapped and Solvated Electrons in Ps Formation

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    Role of trapped and solvated electrons in Ps formation is discussed. Combination of thermalized positron with such electrons is possible from the viewpoint of the energy balance and may results in Ps formation. This process proceeds during all e+\text{}^{+} lifetime in matter. Fitting of raw experimental e+\text{}^{+} - e−\text{}^{-} annihilation spectra has to be based on an adequate physical input, which often leads to necessity of nonexponential deconvolution of the spectra. We have interpreted the Ps formation data in polyethylene, ethylene-methylmethacrylate and polymethylmethacrylate in dark and in light vs. time of the measurement and temperature. Parameters characterized accumulation of trapped electrons and their recombination with counter ions and positrons are obtained
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