Effective Rheology of Bubbles Moving in a Capillary Tube

We calculate the average volumetric flux versus pressure drop of bubbles moving in a single capillary tube with varying diameter, finding a square-root relation from mapping the flow equations onto that of a driven overdamped pendulum. The calculation is based on a derivation of the equation of motion of a bubble train from considering the capillary forces and the entropy production associated with the viscous flow. We also calculate the configurational probability of the positions of the bubbles.Comment: 4 pages, 1 figur

Elliptic flow of charged particles in Pb-Pb collisions at 2.76 TeV

We report the first measurement of charged particle elliptic flow in Pb-Pb collisions at 2.76 TeV with the ALICE detector at the CERN Large Hadron Collider. The measurement is performed in the central pseudorapidity region (|$\eta$|<0.8) and transverse momentum range 0.2< $p_{\rm T}$< 5.0 GeV/$c$. The elliptic flow signal v$_2$, measured using the 4-particle correlation method, averaged over transverse momentum and pseudorapidity is 0.087 $\pm$ 0.002 (stat) $\pm$ 0.004 (syst) in the 40-50% centrality class. The differential elliptic flow v$_2(p_{\rm T})$ reaches a maximum of 0.2 near $p_{\rm T}$ = 3 GeV/$c$. Compared to RHIC Au-Au collisions at 200 GeV, the elliptic flow increases by about 30%. Some hydrodynamic model predictions which include viscous corrections are in agreement with the observed increase.Comment: 10 pages, 4 captioned figures, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/389

The 'Harmonizing Optimal Strategy for Treatment of coronary artery stenosis - sAfety & effectiveneSS of drug-elUting stents & antiplatelet REgimen' (HOST-ASSURE) trial: study protocol for a randomized controlled trial

<p>Abstract</p> <p>Background</p> <p>Second-generation drug-eluting stents (DES) have raised the bar of clinical performance. These stents are mostly made from cobalt chromium alloy. A newer generation DES has been developed from platinum chromium alloy, but clinical data regarding the efficacy and safety of the platinum chromium-based everolimus-eluting stent (PtCr-EES) is limited, with no comparison data against the cobalt chromium-based zotarolimus-eluting stent (CoCr-ZES). In addition, an antiplatelet regimen is an integral component of medical therapy after percutaneous coronary intervention (PCI). A 1-week duration of doubling the dose of clopidogrel (double-dose antiplatelet therapy (DDAT)) was shown to improve outcome at 1 month compared with conventional dose in acute coronary syndrome (ACS) patients undergoing PCI. However in Asia, including Korea, the addition of cilostazol (triplet antiplatelet therapy (TAT)) is used more commonly than doubling the dose of clopidogrel in high-risk patients.</p> <p>Methods</p> <p>In the 'Harmonizing Optimal Strategy for Treatment of coronary artery stenosis - sAfety & effectiveneSS of drug-elUting stents & antiplatelet REgimen' (HOST-ASSURE) trial, approximately 3,750 patients are being prospectively and randomly assigned in a 2 × 2 factorial design according to the type of stent (PtCr-EES vs CoCr-ZES) and antiplatelet regimen (TAT vs DDAT). The first primary endpoint is target lesion failure at 1 year for the stent comparison, and the second primary endpoint is net clinical outcome at 1 month for comparison of antiplatelet therapy regimen.</p> <p>Discussion</p> <p>The HOST-ASSURE trial is the largest study yet performed to directly compare the efficacy and safety of the PtCr-EES versus CoCr-ZES in an 'all-comers' population. In addition, this study will also compare the clinical outcome of TAT versus DDAT for 1-month post PCI.</p> <p>Trial registration</p> <p>ClincalTrials.gov number <a href="http://www.clinicaltrials.gov/ct2/show/NCT01267734">NCT01267734</a>.</p

Long-term Safety and Efficacy of New-Generation Drug-Eluting Stents inWomenWith AcuteMyocardial Infarction From theWomen in Innovation and Drug-Eluting Stents (WIN-DES) Collaboration

Importance Women with acute myocardial infarction (MI) undergoing mechanical reperfusion remain at increased risk of adverse cardiac events and mortality compared with their male counterparts. Whether the benefits of new-generation drug-eluting stents (DES) are preserved in women with acute MI remains unclear. Objective To investigate the long-term safety and efficacy of new-generation DES vs early-generation DES in women with acute MI. Design, Setting, and Participants Collaborative, international, individual patient-level data of women enrolled in 26 randomized clinical trials of DES were analyzed between July and December 2016. Only women presenting with an acute coronary syndrome were included. Study population was categorized according to presentation with unstable angina (UA) vs acute MI. Acute MI included non–ST-segment elevation MI (NSTEMI) or ST-segment elevation MI (STEMI). Interventions Randomization to early- (sirolimus- or paclitaxel-eluting stents) vs new-generation (everolimus-, zotarolimus-, or biolimus-eluting stents) DES. Main Outcomes and Measures Composite of death, MI or target lesion revascularization, and definite or probable stent thrombosis at 3-year follow-up. Results Overall, the mean age of participants was 66.8 years. Of 11 577 women included in the pooled data set, 4373 (37.8%) had an acute coronary syndrome as clinical presentation. Of these 4373 women, 2176 (49.8%) presented with an acute MI. In women with acute MI, new-generation DES were associated with lower risk of death, MI or target lesion revascularization (14.9% vs 18.4%; absolute risk difference, −3.5%; number needed to treat [NNT], 29; adjusted hazard ratio, 0.78; 95% CI, 0.61-0.99), and definite or probable stent thrombosis (1.4% vs 4.0%; absolute risk difference, −2.6%; NNT, 46; adjusted hazard ratio, 0.36; 95% CI, 0.19-0.69) without evidence of interaction for both end points compared with women without acute MI (P for interaction = .59 and P for interaction = .31, respectively). A graded absolute benefit with use of new-generation DES was observed in the transition from UA, to NSTEMI, and to STEMI (for death, MI, or target lesion revascularization: UA, −0.5% [NNT, 222]; NSTEMI, −3.1% [NNT, 33]; STEMI, −4.0% [NNT, 25] and for definite or probable ST: UA, −0.4% [NNT, 278]; NSTEMI, −2.2% [NNT, 46]; STEMI, −4.0% [NNT, 25]). Conclusions and Relevance New-generation DES are associated with consistent and durable benefits over 3 years in women presenting with acute MI. The magnitude of these benefits appeared to be greater per increase in severity of acute coronary syndrome