644 research outputs found

    Global Λ\Lambda Polarization in high energy collisions

    Get PDF
    With a Yang-Mills flux-tube initial state and a high resolution (3+1)D Particle-in-Cell Relativistic (PICR) hydrodynamics simulation, we calculate the Λ\Lambda polarization for different energies. The origination of polarization in high energy collisions is discussed, and we find linear impact parameter dependence of the global Λ\Lambda polarization. Furthermore, the global Λ\Lambda polarization in our model decreases very fast in the low energy domain, and the decline curve fits well the recent results of Beam Energy Scan (BES) program launched by the STAR collaboration at the Relativistic Heavy Ion Collider (RHIC). The time evolution of polarization is also discussed

    Lambda Polarization in an Exact Rotating and Expanding fluid dynamical model for peripheral heavy ion reactions

    Full text link
    We calculate the Lambda polarization in an exact analytical, rotating model based on parameters extracted from a high resolution (3+1)D Particle-in-Cell Relativistic hydrodynamics calculation. The polarization is attributed to effects from thermal vorticity and for the first time the effects of the radial and axial acceleration are also studied separatel

    Investigate the Λ\Lambda and Λˉ\bar{\Lambda} polarization splitting effect with combined mechanisms

    Full text link
    The significant splitting of Λ\Lambda and Λˉ\bar{\Lambda} polarization measured in STAR's Au+Au 7.7GeV collisions seems to be huge and unable to be described satisfactorily by any single mechanism, thus we revisit and combine there different mechanisms together on the basis of our PICR hydrodynamic model, to explain the experimental data. The three mechanisms, i.e. the meson field mechanism, the freeze-out space-time mechanism, and the QGP's magnetic field mechanism, lie on different stage of high energy collisions, and thus are not contradicted with each other. We find that the meson field mechanism is dominat, while the QGP's magnetic field mechanism is rather trivial, and freeze-out time effect is restricted by the small FZ time difference, leading to a hierarchy of ΔPJ≫ΔPt≫ΔPm\Delta P_J \gg \Delta P_t \gg \Delta P_m. Besides, the combination of different mechanisms could promote the mean value of polarization splitting from about 3\%-4\% to 4.5\%, which is more close to the experimental measured mean value of 5.8\%

    Learning Task Skills and Goals Simultaneously from Physical Interaction

    Full text link
    In real-world human-robot systems, it is essential for a robot to comprehend human objectives and respond accordingly while performing an extended series of motor actions. Although human objective alignment has recently emerged as a promising paradigm in the realm of physical human-robot interaction, its application is typically confined to generating simple motions due to inherent theoretical limitations. In this work, our goal is to develop a general formulation to learn manipulation functional modules and long-term task goals simultaneously from physical human-robot interaction. We show the feasibility of our framework in enabling robots to align their behaviors with the long-term task objectives inferred from human interactions.Comment: 2 pages, 1 figure. Accepted by CASE 2023 Special Session on The Next-Generation Resilient Cyber-Physical Manufacturing Network

    COVID−19 hospitalization increases the risk of developing glioblastoma: a bidirectional Mendelian-randomization study

    Get PDF
    BackgroundAs a result of the COVID-19 pandemic, patients with glioblastoma (GBM) are considered a highly vulnerable population. Despite this, the extent of the causative relationship between GBM and COVID-19 infection is uncertain.MethodsGenetic instruments for SARS-CoV-2 infection (38,984 cases and 1,644,784 control individuals), COVID-19 hospitalization (8,316 cases and 1,549,095 control individuals), and COVID-19 severity (4,792 cases and 1,054,664 control individuals) were obtained from a genome-wide association study (GWAS) from European populations. A total of 6,183 GBM cases and 18,169 controls from GWAS were enrolled in our study. Their associations were evaluated by applying Mendelian randomization (MR) including IVW meta-analysis, MR-Egger regression, and weighted-median analysis. To make the conclusions more robust and reliable, sensitivity analyses were performed.ResultsOur results showed that genetically predicted COVID−19 hospitalization increases the risk of GBM (OR = 1.202, 95% CI = 1.035–1.395, p = 0.016). In addition, no increased risk of SARS-CoV-2 infection, COVID-19 hospitalization and severity were observed in patients with any type of genetically predicted GBM.ConclusionOur MR study indicated for the first time that genetically predicted COVID−19 hospitalization was demonstrated as a risk factor for the development of GBM

    Clopidogrel with aspirin in High-risk patients with Acute Non-disabling Cerebrovascular Events II (CHANCE-2): rationale and design of a multicenter randomised trial

    Get PDF
    Background: In patients with a minor ischaemic stroke or transient ischaemic attack (TIA), separate trials have shown that dual antiplatelet therapy with clopidogrel plus aspirin (clopidogrel–aspirin) or ticagrelor plus aspirin (ticagrelor–aspirin) are more effective than aspirin alone in stroke secondary prevention. However, these two sets of combination have not been directly compared. Since clopidogrel was less effective in stroke patients who were CYP2C19 loss-of-function (LOF) allele carriers, whether ticagrelor–aspirin is clinically superior to clopidogrel–aspirin in this subgroup of patients with stroke is unclear.Aim: To describe the rationale and design considerations of the Clopidogrel in High-risk patients with Acute Non-disabling Cerebrovascular Events (CHANCE-2) trial.Design: CHANCE-2 is a randomised, double-blind, double-dummy, placebo-controlled, multicentre trial that compares two dual antiplatelet strategies for minor stroke or TIA patients who are CYP2C19 LOF allele carriers: ticagrelor (180 mg loading dose on day 1 followed by 90 mg twice daily on days 2–90) or clopidogrel (300 mg loading dose on day 1 followed by 75 mg daily on days 2–90), plus open-label aspirin with a dose of 75–300 mg on day 1 followed by 75 mg daily on day 2–21. All will be followed for 1 year.Study outcomes: The primary efficacy outcome is any stroke (ischaemic or haemorrhagic) within 3 months and the primary safety outcome is any severe or moderate bleeding event within 3 months.Discussion: The CHANCE-2 trial will evaluate whether ticagrelor–aspirin is superior to clopidogrel–aspirin for minor stroke or TIA patients who are CYP2C19 LOF allele carriers

    Association of CYP2C19 Loss-of-Function Metabolizer Status With Stroke Risk Among Chinese Patients Treated With Ticagrelor-Aspirin vs Clopidogrel-Aspirin: A Prespecified Secondary Analysis of a Randomized Clinical Trial.

    Get PDF
    Importance: The Clopidogrel With Aspirin in High-Risk Patients With Acute Nondisabling Cerebrovascular Events II (CHANCE-2) trial showed that ticagrelor-aspirin combination therapy reduced the risk of stroke compared with a clopidogrel-aspirin combination among carriers of CYP2C19 loss-of-function (LOF) alleles after a transient ischemic attack (TIA) or minor ischemic stroke. However, the association between the degree of CYP2C19 LOF and ideal treatment allocation remains unknown.Objective: To investigate whether the efficacy and safety of ticagrelor-aspirin vs clopidogrel-aspirin are consistent with the expected degree of CYP2C19 LOF after TIA or minor stroke.Design, Setting, and Participants: CHANCE-2 was a multicenter, double-blind, double-dummy, placebo-controlled randomized clinical trial. Patients were enrolled at 202 centers in China from September 23, 2019, through March 22, 2021. Patients with at least two *2 or *3 alleles (*2/*2, *2/*3, or *3/*3) according to point-of-care genotyping were classified as “poor metabolizers,” and those with one *2 or *3 allele (*1/*2 or *1/*3) were classified as “intermediate metabolizers.”Interventions: Patients were randomly assigned in a 1:1 ratio to receive ticagrelor (180-mg loading dose on day 1 followed by 90 mg twice daily for days 2-90) or clopidogrel (300-mg loading dose on day 1 followed by 75 mg/d for days 2-90). All patients received aspirin (75- to 300-mg loading dose followed by 75 mg/d for 21 days).Main Outcomes and Measures: The primary efficacy outcome was a new ischemic or hemorrhagic stroke. The secondary efficacy outcome was a composite of new clinical vascular events and individual ischemic stroke events within 3 months. The primary safety outcome was severe or moderate bleeding. Analyses were performed according to the intention-to-treat principle.Results: Of the 6412 patients enrolled, the median age was 64.8 years (IQR, 57.0-71.4 years), and 4242 patients (66.2%) were men. Of the 6412 patients, 5001 (78.0%) were intermediate metabolizers, and 1411 (22.0%) were poor metabolizers. The primary outcome occurred less often with ticagrelor-aspirin vs clopidogrel-aspirin, irrespective of metabolizer status (6.0% [150 of 2486] vs 7.6% [191 of 2515]; hazard ratio [HR], 0.78 [95% CI, 0.63-0.97] among intermediate metabolizers and 5.7% [41 of 719] vs 7.5% [52 of 692]; HR, 0.77 [95% CI, 0.50-1.18] among poor metabolizers; P = .88 for interaction). Patients taking ticagrelor-aspirin had a higher risk of any bleeding event compared with those taking clopidogrel-aspirin, irrespective of metabolizer status: 5.4% (134 of 2486) vs 2.6% (66 of 2512) (HR, 2.14 [95% CI, 1.59-2.89]) among intermediate metabolizers and 5.0% (36 of 719) vs 2.0% (14 of 692) (HR, 2.99 [95% CI, 1.51-5.93]) among poor metabolizers (P = .66 for interaction).Conclusions and Relevance: This prespecified analysis of a randomized clinical trial found no difference in treatment effect between poor and intermediate CYP2C19 metabolizers. The relative clinical efficacy and safety of ticagrelor-aspirin vs clopidogrel-aspirin were consistent across CYP2C19 genotypes.Trial Registration: ClinicalTrials.gov Identifier: NCT0407873

    Ticagrelor vs Clopidogrel in CYP2C19 loss-of-function carriers with Stroke or TIA

    Get PDF
    BACKGROUNDComparisons between ticagrelor- aspirin and clopidogrel-aspirin in CYP2C19 loss-of-function carriers have not been well studied for secondary stroke prevention.METHODSWe conducted a randomized, double-blind, placebo-controlled trial of 6,412 patients with a minor ischemic stroke or TIA who carried CYP2C19 LOF alleles determined by point-of-care testing. Patients were randomly assigned within 24 hours after symptom onset, in a 1:1 ratio to receive ticagrelor (180 mg loading dose on day 1 followed by 90 mg twice daily for days 2 through 90) or clopidogrel (300 mg loading dose on day 1 followed by 75 mg per day for days 2 through 90), plus aspirin (75-300 mg loading dose followed by 75 mg daily for 21 days). The primary efficacy outcome was stroke and the primary safety outcome was severe or moderate bleeding, both within 90 days. RESULTSStroke occurred within 90 days in 191 (6.0%) versus 243 (7.6%), respectively (hazard ratio, 0.77; 95% confidence interval, 0.64 to 0.94; P=0.008). Moderate or severe bleeding occurred in 9 patients (0.3%) in the ticagrelor-aspirin group and in 11 patients (0.3%) in the clopidogrel-aspirin group; any bleeding event occurred in 170 patients (5.3%) vs 80 (2.5%), respectively. CONCLUSIONSAmong Chinese patients with minor ischemic stroke or TIA within 24 hours after symptoms onset who were carriers of CYP2C19 loss-of-function alleles, ticagrelor- aspirin was modestly better than clopidogrel-aspirin for reducing the risk of stroke but was associated with more total bleeding events at 90 days. (CHANCE-2 ClinicalTrials.gov number, NCT04078737.

    Rotation and Polarization in Heavy Ion Collisions

    No full text

    Λ polarization in an exact fluid dynamical model for heavy-ion collisions

    Get PDF
    Λ polarization is calculated in an exact analytical, rotating model based on parameters from a high resolution (3+1)D Particle-in-Cell Relativistic hydrodynamics calculation. The polarization is attributed to effects from thermal vorticity and for the first time the effects of the radial and axial acceleration are also studied separately
    • 

    corecore