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Hyperon Polarization along the Beam Direction Relative to the Second and Third Harmonic Event Planes in Isobar Collisions at sqrt[s_{NN}]=200 GeV. PHYSICAL REVIEW LETTERS 2023; 131:202301. [PMID: 38039468 DOI: 10.1103/physrevlett.131.202301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 07/07/2023] [Accepted: 10/03/2023] [Indexed: 12/03/2023]
Abstract
The polarization of Λ and Λ[over ¯] hyperons along the beam direction has been measured relative to the second and third harmonic event planes in isobar Ru+Ru and Zr+Zr collisions at sqrt[s_{NN}]=200 GeV. This is the first experimental evidence of the hyperon polarization by the triangular flow originating from the initial density fluctuations. The amplitudes of the sine modulation for the second and third harmonic results are comparable in magnitude, increase from central to peripheral collisions, and show a mild p_{T} dependence. The azimuthal angle dependence of the polarization follows the vorticity pattern expected due to elliptic and triangular anisotropic flow, and qualitatively disagrees with most hydrodynamic model calculations based on thermal vorticity and shear induced contributions. The model results based on one of existing implementations of the shear contribution lead to a correct azimuthal angle dependence, but predict centrality and p_{T} dependence that still disagree with experimental measurements. Thus, our results provide stringent constraints on the thermal vorticity and shear-induced contributions to hyperon polarization. Comparison to previous measurements at RHIC and the LHC for the second-order harmonic results shows little dependence on the collision system size and collision energy.
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Erratum: Global Polarization of Ξ and Ω Hyperons in Au+Au Collisions at sqrt[s_{NN}]=200 GeV [Phys. Rev. Lett. 126, 162301 (2021)]. PHYSICAL REVIEW LETTERS 2023; 131:089901. [PMID: 37683178 DOI: 10.1103/physrevlett.131.089901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Indexed: 09/10/2023]
Abstract
This corrects the article DOI: 10.1103/PhysRevLett.126.162301.
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Measurements of the Elliptic and Triangular Azimuthal Anisotropies in Central ^{3}He+Au, d+Au and p+Au Collisions at sqrt[s_{NN}]=200 GeV. PHYSICAL REVIEW LETTERS 2023; 130:242301. [PMID: 37390421 DOI: 10.1103/physrevlett.130.242301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 02/27/2023] [Accepted: 05/15/2023] [Indexed: 07/02/2023]
Abstract
The elliptic (v_{2}) and triangular (v_{3}) azimuthal anisotropy coefficients in central ^{3}He+Au, d+Au, and p+Au collisions at sqrt[s_{NN}]=200 GeV are measured as a function of transverse momentum (p_{T}) at midrapidity (|η|<0.9), via the azimuthal angular correlation between two particles both at |η|<0.9. While the v_{2}(p_{T}) values depend on the colliding systems, the v_{3}(p_{T}) values are system independent within the uncertainties, suggesting an influence on eccentricity from subnucleonic fluctuations in these small-sized systems. These results also provide stringent constraints for the hydrodynamic modeling of these systems.
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Observation of Directed Flow of Hypernuclei _{Λ}^{3}H and _{Λ}^{4}H in sqrt[s_{NN}]=3 GeV Au+Au Collisions at RHIC. PHYSICAL REVIEW LETTERS 2023; 130:212301. [PMID: 37295104 DOI: 10.1103/physrevlett.130.212301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/24/2023] [Accepted: 03/02/2023] [Indexed: 06/12/2023]
Abstract
We report here the first observation of directed flow (v_{1}) of the hypernuclei _{Λ}^{3}H and _{Λ}^{4}H in mid-central Au+Au collisions at sqrt[s_{NN}]=3 GeV at RHIC. These data are taken as part of the beam energy scan program carried out by the STAR experiment. From 165×10^{6} events in 5%-40% centrality, about 8400 _{Λ}^{3}H and 5200 _{Λ}^{4}H candidates are reconstructed through two- and three-body decay channels. We observe that these hypernuclei exhibit significant directed flow. Comparing to that of light nuclei, it is found that the midrapidity v_{1} slopes of _{Λ}^{3}H and _{Λ}^{4}H follow baryon number scaling, implying that the coalescence is the dominant mechanism for these hypernuclei production in the 3 GeV Au+Au collisions.
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Beam Energy Dependence of Triton Production and Yield Ratio (N_{t}×N_{p}/N_{d}^{2}) in Au+Au Collisions at RHIC. PHYSICAL REVIEW LETTERS 2023; 130:202301. [PMID: 37267557 DOI: 10.1103/physrevlett.130.202301] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 02/21/2023] [Accepted: 03/30/2023] [Indexed: 06/04/2023]
Abstract
We report the triton (t) production in midrapidity (|y|<0.5) Au+Au collisions at sqrt[s_{NN}]=7.7-200 GeV measured by the STAR experiment from the first phase of the beam energy scan at the Relativistic Heavy Ion Collider. The nuclear compound yield ratio (N_{t}×N_{p}/N_{d}^{2}), which is predicted to be sensitive to the fluctuation of local neutron density, is observed to decrease monotonically with increasing charged-particle multiplicity (dN_{ch}/dη) and follows a scaling behavior. The dN_{ch}/dη dependence of the yield ratio is compared to calculations from coalescence and thermal models. Enhancements in the yield ratios relative to the coalescence baseline are observed in the 0%-10% most central collisions at 19.6 and 27 GeV, with a significance of 2.3σ and 3.4σ, respectively, giving a combined significance of 4.1σ. The enhancements are not observed in peripheral collisions or model calculations without critical fluctuation, and decreases with a smaller p_{T} acceptance. The physics implications of these results on the QCD phase structure and the production mechanism of light nuclei in heavy-ion collisions are discussed.
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Measurement of Sequential ϒ Suppression in Au+Au Collisions at sqrt[s_{NN}]=200 GeV with the STAR Experiment. PHYSICAL REVIEW LETTERS 2023; 130:112301. [PMID: 37001106 DOI: 10.1103/physrevlett.130.112301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 11/30/2022] [Accepted: 01/26/2023] [Indexed: 06/19/2023]
Abstract
We report on measurements of sequential ϒ suppression in Au+Au collisions at sqrt[s_{NN}]=200 GeV with the STAR detector at the Relativistic Heavy Ion Collider (RHIC) through both the dielectron and dimuon decay channels. In the 0%-60% centrality class, the nuclear modification factors (R_{AA}), which quantify the level of yield suppression in heavy-ion collisions compared to p+p collisions, for ϒ(1S) and ϒ(2S) are 0.40±0.03(stat)±0.03(sys)±0.09(norm) and 0.26±0.08(stat)±0.02(sys)±0.06(norm), respectively, while the upper limit of the ϒ(3S) R_{AA} is 0.17 at a 95% confidence level. This provides experimental evidence that the ϒ(3S) is significantly more suppressed than the ϒ(1S) at RHIC. The level of suppression for ϒ(1S) is comparable to that observed at the much higher collision energy at the Large Hadron Collider. These results point to the creation of a medium at RHIC whose temperature is sufficiently high to strongly suppress excited ϒ states.
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Beam Energy Dependence of Fifth- and Sixth-Order Net-Proton Number Fluctuations in Au+Au Collisions at RHIC. PHYSICAL REVIEW LETTERS 2023; 130:082301. [PMID: 36898098 DOI: 10.1103/physrevlett.130.082301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 11/21/2022] [Accepted: 01/11/2023] [Indexed: 06/18/2023]
Abstract
We report the beam energy and collision centrality dependence of fifth and sixth order cumulants (C_{5}, C_{6}) and factorial cumulants (κ_{5}, κ_{6}) of net-proton and proton number distributions, from center-of-mass energy (sqrt[s_{NN}]) 3 GeV to 200 GeV Au+Au collisions at RHIC. Cumulant ratios of net-proton (taken as proxy for net-baryon) distributions generally follow the hierarchy expected from QCD thermodynamics, except for the case of collisions at 3 GeV. The measured values of C_{6}/C_{2} for 0%-40% centrality collisions show progressively negative trend with decreasing energy, while it is positive for the lowest energy studied. These observed negative signs are consistent with QCD calculations (for baryon chemical potential, μ_{B}≤110 MeV) which contains the crossover transition range. In addition, for energies above 7.7 GeV, the measured proton κ_{n}, within uncertainties, does not support the two-component (Poisson+binomial) shape of proton number distributions that would be expected from a first-order phase transition. Taken in combination, the hyperorder proton number fluctuations suggest that the structure of QCD matter at high baryon density, μ_{B}∼750 MeV at sqrt[s_{NN}]=3 GeV is starkly different from those at vanishing μ_{B}∼24 MeV at sqrt[s_{NN}]=200 GeV and higher collision energies.
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HEAT AND MASS TRANSPORT FOR ELASTICO-VISCOUS FLUID WITH PARTIAL SLIP BOUNDARY OVER A FLAT PERMEABLE PLATE. LATIN AMERICAN APPLIED RESEARCH - AN INTERNATIONAL JOURNAL 2023. [DOI: 10.52292/j.laar.2023.685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
The elastico-viscous boundary layer fluid motion over a flat permeable plate having slip boundary is considered. The transition of thermal energy and mass transport mechanism has been analyzed. The elastic and viscous characteristic in the fluid is exhibited by Walters Liquid (Model , a non-Newtonian fluid model. The permeable plate at which suction is applied is placed in porous medium. The fluid domain receives thermal energy from the permeable plate. The governing equations of fluid motion with satisfying imposed boundary conditions are reduced to self-similar type by similarity transformation. The finite difference method-based solver ‘bvp4c’ of MATLAB code is employed to perform numerical computation. The impact of different involved flow parameters is illustrated from obtained graphs for discussions from physical point of view.
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Rapid Point-of-Care Quantification of Human Serum Albumin in Urine Based on Ratiometric Fluorescence Signaling Driven by Intramolecular H-Bonding. ACS Sens 2022; 7:3790-3799. [PMID: 36413708 DOI: 10.1021/acssensors.2c01684] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Human serum albumin exerts multifunctions, such as maintaining the oncotic pressure of plasma, carrying hydrophobic molecules, and acting as the most important antioxidant in the blood. Lower serum albumin levels are linked to several cardiovascular diseases, and dysfunction of albumin reabsorption in the kidney is linked to liver disease, renal disorder, and diabetes. Albumin is thus a powerful diagnostic and prognostic marker; however, its quantification in urine by readily affordable tools is challenging owing to its very low concentration. To address this issue, we developed a ratiometric fluorescent probe with multiple advantages through a systematic structure variation of a benzocoumarin fluorophore and, further, a prototype of a smartphone-based point-of-care device. We determined albumin levels in urine and observed that a smoking person has notably higher urine albumin than a nonsmoking person. The cheap device provides a promising tool for albumin-associated disease diagnosis in communities with limited resources.
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Collision-System and Beam-Energy Dependence of Anisotropic Flow Fluctuations. PHYSICAL REVIEW LETTERS 2022; 129:252301. [PMID: 36608250 DOI: 10.1103/physrevlett.129.252301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 08/17/2022] [Accepted: 11/16/2022] [Indexed: 06/17/2023]
Abstract
Elliptic flow measurements from two-, four-, and six-particle correlations are used to investigate flow fluctuations in collisions of U+U at sqrt[s_{NN}]=193 GeV, Cu+Au at sqrt[s_{NN}]=200 GeV and Au+Au spanning the range sqrt[s_{NN}]=11.5-200 GeV. The measurements show a strong dependence of the flow fluctuations on collision centrality, a modest dependence on system size, and very little if any, dependence on particle species and beam energy. The results, when compared to similar LHC measurements, viscous hydrodynamic calculations, and trento model eccentricities, indicate that initial-state-driven fluctuations predominate the flow fluctuations generated in the collisions studied.
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Evidence for Nonlinear Gluon Effects in QCD and Their Mass Number Dependence at STAR. PHYSICAL REVIEW LETTERS 2022; 129:092501. [PMID: 36083674 DOI: 10.1103/physrevlett.129.092501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 07/12/2022] [Accepted: 07/29/2022] [Indexed: 06/15/2023]
Abstract
The STAR Collaboration reports measurements of back-to-back azimuthal correlations of di-π^{0}s produced at forward pseudorapidities (2.6<η<4.0) in p+p, p+Al, and p+Au collisions at a center-of-mass energy of 200 GeV. We observe a clear suppression of the correlated yields of back-to-back π^{0} pairs in p+Al and p+Au collisions compared to the p+p data. The observed suppression of back-to-back pairs as a function of transverse momentum suggests nonlinear gluon dynamics arising at high parton densities. The larger suppression found in p+Au relative to p+Al collisions exhibits a dependence of the saturation scale Q_{s}^{2} on the mass number A. A linear scaling of the suppression with A^{1/3} is observed with a slope of -0.09±0.01.
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Measurements of Proton High-Order Cumulants in sqrt[s_{NN}]=3 GeV Au+Au Collisions and Implications for the QCD Critical Point. PHYSICAL REVIEW LETTERS 2022; 128:202303. [PMID: 35657878 DOI: 10.1103/physrevlett.128.202303] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 04/11/2022] [Indexed: 06/15/2023]
Abstract
We report cumulants of the proton multiplicity distribution from dedicated fixed-target Au+Au collisions at sqrt[s_{NN}]=3.0 GeV, measured by the STAR experiment in the kinematic acceptance of rapidity (y) and transverse momentum (p_{T}) within -0.5<y<0 and 0.4<p_{T}<2.0 GeV/c. In the most central 0%-5% collisions, a proton cumulant ratio is measured to be C_{4}/C_{2}=-0.85±0.09 (stat)±0.82 (syst), which is 2σ below the Poisson baseline with respect to both the statistical and systematic uncertainties. The hadronic transport UrQMD model reproduces our C_{4}/C_{2} in the measured acceptance. Compared to higher energy results and the transport model calculations, the suppression in C_{4}/C_{2} is consistent with fluctuations driven by baryon number conservation and indicates an energy regime dominated by hadronic interactions. These data imply that the QCD critical region, if created in heavy-ion collisions, could only exist at energies higher than 3 GeV.
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Measurements of _{Λ}^{3}H and _{Λ}^{4}H Lifetimes and Yields in Au+Au Collisions in the High Baryon Density Region. PHYSICAL REVIEW LETTERS 2022; 128:202301. [PMID: 35657899 DOI: 10.1103/physrevlett.128.202301] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 01/26/2022] [Accepted: 04/05/2022] [Indexed: 06/15/2023]
Abstract
We report precision measurements of hypernuclei _{Λ}^{3}H and _{Λ}^{4}H lifetimes obtained from Au+Au collisions at sqrt[s_{NN}]=3.0 GeV and 7.2 GeV collected by the STAR experiment at the Relativistic Heavy Ion Collider, and the first measurement of _{Λ}^{3}H and _{Λ}^{4}H midrapidity yields in Au+Au collisions at sqrt[s_{NN}]=3.0 GeV. _{Λ}^{3}H and _{Λ}^{4}H, being the two simplest bound states composed of hyperons and nucleons, are cornerstones in the field of hypernuclear physics. Their lifetimes are measured to be 221±15(stat)±19(syst) ps for _{Λ}^{3}H and 218±6(stat)±13(syst) ps for _{Λ}^{4}H. The p_{T}-integrated yields of _{Λ}^{3}H and _{Λ}^{4}H are presented in different centrality and rapidity intervals. It is observed that the shape of the rapidity distribution of _{Λ}^{4}H is different for 0%-10% and 10%-50% centrality collisions. Thermal model calculations, using the canonical ensemble for strangeness, describes the _{Λ}^{3}H yield well, while underestimating the _{Λ}^{4}H yield. Transport models, combining baryonic mean-field and coalescence (jam) or utilizing dynamical cluster formation via baryonic interactions (phqmd) for light nuclei and hypernuclei production, approximately describe the measured _{Λ}^{3}H and _{Λ}^{4}H yields. Our measurements provide means to precisely assess our understanding of the fundamental baryonic interactions with strange quarks, which can impact our understanding of more complicated systems involving hyperons, such as the interior of neutron stars or exotic hypernuclei.
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Probing the Gluonic Structure of the Deuteron with J/ψ Photoproduction in d+Au Ultraperipheral Collisions. PHYSICAL REVIEW LETTERS 2022; 128:122303. [PMID: 35394314 DOI: 10.1103/physrevlett.128.122303] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 01/18/2022] [Accepted: 02/25/2022] [Indexed: 06/14/2023]
Abstract
Understanding gluon density distributions and how they are modified in nuclei are among the most important goals in nuclear physics. In recent years, diffractive vector meson production measured in ultraperipheral collisions (UPCs) at heavy-ion colliders has provided a new tool for probing the gluon density. In this Letter, we report the first measurement of J/ψ photoproduction off the deuteron in UPCs at the center-of-mass energy sqrt[s_{NN}]=200 GeV in d+Au collisions. The differential cross section as a function of momentum transfer -t is measured. In addition, data with a neutron tagged in the deuteron-going zero-degree calorimeter is investigated for the first time, which is found to be consistent with the expectation of incoherent diffractive scattering at low momentum transfer. Theoretical predictions based on the color glass condensate saturation model and the leading twist approximation nuclear shadowing model are compared with the data quantitatively. A better agreement with the saturation model has been observed. With the current measurement, the results are found to be directly sensitive to the gluon density distribution of the deuteron and the deuteron breakup process, which provides insights into the nuclear gluonic structure.
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Search for the Chiral Magnetic Effect via Charge-Dependent Azimuthal Correlations Relative to Spectator and Participant Planes in Au+Au Collisions at sqrt[s_{NN}]=200 GeV. PHYSICAL REVIEW LETTERS 2022; 128:092301. [PMID: 35302834 DOI: 10.1103/physrevlett.128.092301] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 10/11/2021] [Accepted: 02/02/2022] [Indexed: 06/14/2023]
Abstract
The chiral magnetic effect (CME) refers to charge separation along a strong magnetic field due to imbalanced chirality of quarks in local parity and charge-parity violating domains in quantum chromodynamics. The experimental measurement of the charge separation is made difficult by the presence of a major background from elliptic azimuthal anisotropy. This background and the CME signal have different sensitivities to the spectator and participant planes, and could thus be determined by measurements with respect to these planes. We report such measurements in Au+Au collisions at a nucleon-nucleon center-of-mass energy of 200 GeV at the Relativistic Heavy-Ion Collider. It is found that the charge separation, with the flow background removed, is consistent with zero in peripheral (large impact parameter) collisions. Some indication of finite CME signals is seen in midcentral (intermediate impact parameter) collisions. Significant residual background effects may, however, still be present.
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Rationally Designed Two-Photon Ratiometric Elastase Probe for Investigating Inflammatory Bowel Disease. Anal Chem 2022; 94:1373-1381. [DOI: 10.1021/acs.analchem.1c04646] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Measurement of the Sixth-Order Cumulant of Net-Proton Multiplicity Distributions in Au+Au Collisions at sqrt[s_{NN}]=27, 54.4, and 200 GeV at RHIC. PHYSICAL REVIEW LETTERS 2021; 127:262301. [PMID: 35029466 DOI: 10.1103/physrevlett.127.262301] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 08/19/2021] [Accepted: 11/11/2021] [Indexed: 06/14/2023]
Abstract
According to first-principle lattice QCD calculations, the transition from quark-gluon plasma to hadronic matter is a smooth crossover in the region μ_{B}≤T_{c}. In this range the ratio, C_{6}/C_{2}, of net-baryon distributions are predicted to be negative. In this Letter, we report the first measurement of the midrapidity net-proton C_{6}/C_{2} from 27, 54.4, and 200 GeV Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC). The dependence on collision centrality and kinematic acceptance in (p_{T}, y) are analyzed. While for 27 and 54.4 GeV collisions the C_{6}/C_{2} values are close to zero within uncertainties, it is observed that for 200 GeV collisions, the C_{6}/C_{2} ratio becomes progressively negative from peripheral to central collisions. Transport model calculations without critical dynamics predict mostly positive values except for the most central collisions within uncertainties. These observations seem to favor a smooth crossover in the high-energy nuclear collisions at top RHIC energy.
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The hepatic compensatory response to elevated systemic sulfide promotes diabetes. Cell Rep 2021; 37:109958. [PMID: 34758301 PMCID: PMC8595646 DOI: 10.1016/j.celrep.2021.109958] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 07/06/2021] [Accepted: 10/15/2021] [Indexed: 12/12/2022] Open
Abstract
Impaired hepatic glucose and lipid metabolism are hallmarks of type 2 diabetes. Increased sulfide production or sulfide donor compounds may beneficially regulate hepatic metabolism. Disposal of sulfide through the sulfide oxidation pathway (SOP) is critical for maintaining sulfide within a safe physiological range. We show that mice lacking the liver- enriched mitochondrial SOP enzyme thiosulfate sulfurtransferase (Tst-/- mice) exhibit high circulating sulfide, increased gluconeogenesis, hypertriglyceridemia, and fatty liver. Unexpectedly, hepatic sulfide levels are normal in Tst-/- mice because of exaggerated induction of sulfide disposal, with associated suppression of global protein persulfidation and nuclear respiratory factor 2 target protein levels. Hepatic proteomic and persulfidomic profiles converge on gluconeogenesis and lipid metabolism, revealing a selective deficit in medium-chain fatty acid oxidation in Tst-/- mice. We reveal a critical role of TST in hepatic metabolism that has implications for sulfide donor strategies in the context of metabolic disease.
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Ratiometric Detection of Hypochlorous Acid in Brain Tissues of Neuroinflammation and Maternal Immune Activation Models with a Deep-Red/Near-Infrared Emitting Probe. ACS Sens 2021; 6:3253-3261. [PMID: 34467757 DOI: 10.1021/acssensors.1c00930] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Reactive oxygen species (ROS) produced by an inflammatory response in the brain are associated with various neurological disorders. To investigate ROS-associated neuroinflammatory diseases, fluorescent probes with practicality are in demand. We have investigated hypochlorous acid, an important ROS, in the brain tissues of neuroinflammation and maternal immune activation (MIA) model mice, using a new fluorescent probe. The probe has outstanding features over many known probes, such as providing two bright ratio signals in cells and tissues in deep-red/near-infrared wavelength regions with a large spectral separation, in addition to being strongly fluorescent, photo- and chemo-stable, highly selective and sensitive, fast responding, and biocompatible. We have found that the level of hypochlorous acid in the brain tissue of a neuroinflammatory mouse model was higher (2.7-4.0-fold) compared with that in normal brain tissue. Furthermore, the level of hypochlorous acid in the brain tissue of a MIA mouse model was higher (1.2-1.3-fold) compared with that in the normal brain tissue. The "robust" probe provides a practical tool for studying ROS-associated neurological disorders.
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Observation of D_{s}^{±}/D^{0} Enhancement in Au+Au Collisions at sqrt[s_{NN}]=200 GeV. PHYSICAL REVIEW LETTERS 2021; 127:092301. [PMID: 34506181 DOI: 10.1103/physrevlett.127.092301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 05/12/2021] [Accepted: 07/21/2021] [Indexed: 06/13/2023]
Abstract
We report on the first measurement of charm-strange meson D_{s}^{±} production at midrapidity in Au+Au collisions at sqrt[s_{NN}]=200 GeV from the STAR experiment. The yield ratio between strange (D_{s}^{±}) and nonstrange (D^{0}) open-charm mesons is presented and compared to model calculations. A significant enhancement, relative to a pythia simulation of p+p collisions, is observed in the D_{s}^{±}/D^{0} yield ratio in Au+Au collisions over a large range of collision centralities. Model calculations incorporating abundant strange-quark production in the quark-gluon plasma and coalescence hadronization qualitatively reproduce the data. The transverse-momentum integrated yield ratio of D_{s}^{±}/D^{0} at midrapidity is consistent with a prediction from a statistical hadronization model with the parameters constrained by the yields of light and strange hadrons measured at the same collision energy. These results suggest that the coalescence of charm quarks with strange quarks in the quark-gluon plasma plays an important role in D_{s}^{±}-meson production in heavy-ion collisions.
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Measurement of e^{+}e^{-} Momentum and Angular Distributions from Linearly Polarized Photon Collisions. PHYSICAL REVIEW LETTERS 2021; 127:052302. [PMID: 34397228 DOI: 10.1103/physrevlett.127.052302] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 06/17/2021] [Accepted: 06/29/2021] [Indexed: 06/13/2023]
Abstract
The Breit-Wheeler process which produces matter and antimatter from photon collisions is experimentally investigated through the observation of 6085 exclusive electron-positron pairs in ultraperipheral Au+Au collisions at sqrt[s_{NN}]=200 GeV. The measurements reveal a large fourth-order angular modulation of cos4Δϕ=(16.8±2.5)% and smooth invariant mass distribution absent of vector mesons (ϕ, ω, and ρ) at the experimental limit of ≤0.2% of the observed yields. The differential cross section as a function of e^{+}e^{-} pair transverse momentum P_{⊥} peaks at low value with sqrt[⟨P_{⊥}^{2}⟩]=38.1±0.9 MeV and displays a significant centrality dependence. These features are consistent with QED calculations for the collision of linearly polarized photons quantized from the extremely strong electromagnetic fields generated by the highly charged Au nuclei at ultrarelativistic speed. The experimental results have implications for vacuum birefringence and for mapping the magnetic field which is important for emergent QCD phenomena.
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Role of gas flow on plasma stream dynamics in a pulsed plasma accelerator. FUSION ENGINEERING AND DESIGN 2021. [DOI: 10.1016/j.fusengdes.2021.112400] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Measurement of transverse single-spin asymmetries of
π0
and electromagnetic jets at forward rapidity in 200 and 500 GeV transversely polarized proton-proton collisions. Int J Clin Exp Med 2021. [DOI: 10.1103/physrevd.103.092009] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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24
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Global Polarization of Ξ and Ω Hyperons in Au+Au Collisions at sqrt[s_{NN}]=200 GeV. PHYSICAL REVIEW LETTERS 2021; 126:162301. [PMID: 33961449 DOI: 10.1103/physrevlett.126.162301] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Accepted: 04/01/2021] [Indexed: 06/12/2023]
Abstract
Global polarization of Ξ and Ω hyperons has been measured for the first time in Au+Au collisions at sqrt[s_{NN}]=200 GeV. The measurements of the Ξ^{-} and Ξ[over ¯]^{+} hyperon polarization have been performed by two independent methods, via analysis of the angular distribution of the daughter particles in the parity violating weak decay Ξ→Λ+π, as well as by measuring the polarization of the daughter Λ hyperon, polarized via polarization transfer from its parent. The polarization, obtained by combining the results from the two methods and averaged over Ξ^{-} and Ξ[over ¯]^{+}, is measured to be ⟨P_{Ξ}⟩=0.47±0.10(stat)±0.23(syst)% for the collision centrality 20%-80%. The ⟨P_{Ξ}⟩ is found to be slightly larger than the inclusive Λ polarization and in reasonable agreement with a multiphase transport model. The ⟨P_{Ξ}⟩ is found to follow the centrality dependence of the vorticity predicted in the model, increasing toward more peripheral collisions. The global polarization of Ω, ⟨P_{Ω}⟩=1.11±0.87(stat)±1.97(syst)% was obtained by measuring the polarization of daughter Λ in the decay Ω→Λ+K, assuming the polarization transfer factor C_{ΩΛ}=1.
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Nonmonotonic Energy Dependence of Net-Proton Number Fluctuations. PHYSICAL REVIEW LETTERS 2021; 126:092301. [PMID: 33750161 DOI: 10.1103/physrevlett.126.092301] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 11/19/2020] [Accepted: 01/27/2021] [Indexed: 06/12/2023]
Abstract
Nonmonotonic variation with collision energy (sqrt[s_{NN}]) of the moments of the net-baryon number distribution in heavy-ion collisions, related to the correlation length and the susceptibilities of the system, is suggested as a signature for the quantum chromodynamics critical point. We report the first evidence of a nonmonotonic variation in the kurtosis times variance of the net-proton number (proxy for net-baryon number) distribution as a function of sqrt[s_{NN}] with 3.1 σ significance for head-on (central) gold-on-gold (Au+Au) collisions measured solenoidal tracker at Relativistic Heavy Ion Collider. Data in noncentral Au+Au collisions and models of heavy-ion collisions without a critical point show a monotonic variation as a function of sqrt[s_{NN}].
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26
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A Study on Hypoxia Susceptibility of Organ Tissues by Fluorescence Imaging with a Ratiometric Nitroreductase Probe. ACS Sens 2021; 6:148-155. [PMID: 33334101 DOI: 10.1021/acssensors.0c01989] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Hypoxia, a condition of oxygen deficiency in tissues, features various diseases including solid tumor. Under hypoxia, several reductases such as nitroreductases are elevated. Based on this fact, we have investigated an indirect way to assess the hypoxia susceptibility of different organ tissues (mouse lung, heart, spleen, kidney, and liver) by detecting nitroreductase present within. Among the organs, the kidney showed a notable susceptibility to hypoxia, which was due to the renal medulla, not due to the renal cortex, as observed by ratiometric fluorescence imaging with a probe. The probe features ratiometric signaling, NIR-emitting, two-photon absorbing, and pH-insensitive emission properties, offering a practical tool for studying the nitroreductase activity and, furthermore, hypoxia-associated biological processes.
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27
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First Measurement of Λ_{c} Baryon Production in Au+Au Collisions at sqrt[s_{NN}]=200 GeV. PHYSICAL REVIEW LETTERS 2020; 124:172301. [PMID: 32412276 DOI: 10.1103/physrevlett.124.172301] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 02/24/2020] [Accepted: 03/27/2020] [Indexed: 06/11/2023]
Abstract
We report on the first measurement of the charmed baryon Λ_{c}^{±} production at midrapidity (|y|<1) in Au+Au collisions at sqrt[s_{NN}]=200 GeV collected by the STAR experiment at the Relativistic Heavy Ion Collider. The Λ_{c}/D^{0} [denoting (Λ_{c}^{+}+Λ_{c}^{-})/(D^{0}+D[over ¯]^{0})] yield ratio is measured to be 1.08±0.16 (stat)±0.26 (sys) in the 0%-20% most central Au+Au collisions for the transverse momentum (p_{T}) range 3<p_{T}<6 GeV/c. This is significantly larger than the pythia model calculations for p+p collisions. The measured Λ_{c}/D^{0} ratio, as a function of p_{T} and collision centrality, is comparable to the baryon-to-meson ratios for light and strange hadrons in Au+Au collisions. Model calculations including coalescence hadronization for charmed baryon and meson formation reproduce the features of our measured Λ_{c}/D^{0} ratio.
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28
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A systematic study on the discrepancy of fluorescence properties between in solutions and in cells: super-bright, environment-insensitive benzocoumarin dyes. Chem Commun (Camb) 2020; 56:10556-10559. [DOI: 10.1039/d0cc03586f] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The benzocoumarins show distinctive emission behaviour from some commonly-used dyes in organic, aqueous buffer, and cellular media, which compels us to recognize the cellular environment as the third space for fluorophores.
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29
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Far-red/near-infrared emitting, two-photon absorbing, and bio-stable amino-Si-pyronin dyes. Chem Sci 2019; 10:9028-9037. [PMID: 31762981 PMCID: PMC6855311 DOI: 10.1039/c9sc02287b] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 08/03/2019] [Indexed: 12/12/2022] Open
Abstract
Organic fluorophores emitting in the far-red/near-infrared (NIR) wavelength region are in great demand for minimal autofluorescence and reduced light scattering in deep tissue or whole body imaging. Currently, only a few classes of far-red/NIR fluorophores are available including widely used cyanine dyes, which are susceptible to photobleaching and form nonfluorescent aggregates. Even rare are those far-red/NIR emitting dyes that have two-photon imaging capability. Here we report a new class of far-red/NIR-emitting dyes that are photo-stable, very bright, biocompatible, and also two-photon absorbing. The introduction of an electron-withdrawing group such as N-acyl or N-alkoxycarbonyl groups on the C-10-amino substituent of the new julolidine-derived amino-Si-pyronin dyes (ASiPj), which emit in the far-red region, causes large bathochromic shifts, leading to NIR-emitting amino-Si-pyronin dyes (NIR-ASiPj) having high cellular stability. Furthermore, the ASiPj-NIR-ASiPj couple offers a novel ratiometric bioimaging platform with a large spectral gap, as demonstrated here with a boronate-containing NIR-ASiPj derivative that is converted to the corresponding ASiPj dye upon reaction with hydrogen peroxide.
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First Observation of the Directed Flow of D^{0} and D^{0}[over ¯] in Au+Au Collisions at sqrt[s_{NN}]=200 GeV. PHYSICAL REVIEW LETTERS 2019; 123:162301. [PMID: 31702332 DOI: 10.1103/physrevlett.123.162301] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 08/09/2019] [Indexed: 06/10/2023]
Abstract
We report the first measurement of rapidity-odd directed flow (v_{1}) for D^{0} and D^{0}[over ¯] mesons at midrapidity (|y|<0.8) in Au+Au collisions at sqrt[s_{NN}]=200 GeV using the STAR detector at the Relativistic Heavy Ion Collider. In 10-80% Au+Au collisions, the slope of the v_{1} rapidity dependence (dv_{1}/dy), averaged over D^{0} and D^{0}[over ¯] mesons, is -0.080±0.017(stat)±0.016(syst) for transverse momentum p_{T} above 1.5 GeV/c. The absolute value of D^{0} meson dv_{1}/dy is about 25 times larger than that for charged kaons, with 3.4σ significance. These data give a unique insight into the initial tilt of the produced matter, and offer constraints on the geometric and transport parameters of the hot QCD medium created in relativistic heavy-ion collisions.
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31
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Polarization of Λ (Λ[over ¯]) Hyperons along the Beam Direction in Au+Au Collisions at sqrt[s_{NN}]=200 GeV. PHYSICAL REVIEW LETTERS 2019; 123:132301. [PMID: 31697517 DOI: 10.1103/physrevlett.123.132301] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 08/21/2019] [Indexed: 06/10/2023]
Abstract
The Λ (Λ[over ¯]) hyperon polarization along the beam direction has been measured in Au+Au collisions at sqrt[s_{NN}]=200 GeV, for the first time in heavy-ion collisions. The polarization dependence on the hyperons' emission angle relative to the elliptic flow plane exhibits a second harmonic sine modulation, indicating a quadrupole pattern of the vorticity component along the beam direction, expected due to elliptic flow. The polarization is found to increase in more peripheral collisions, and shows no strong transverse momentum (p_{T}) dependence at p_{T} greater than 1 GeV/c. The magnitude of the signal is about 5 times smaller than those predicted by hydrodynamic and multiphase transport models; the observed phase of the emission angle dependence is also opposite to these model predictions. In contrast, the kinematic vorticity calculations in the blast-wave model tuned to reproduce particle spectra, elliptic flow, and the azimuthal dependence of the Gaussian source radii measured with the Hanbury Brown-Twiss intensity interferometry technique reproduce well the modulation phase measured in the data and capture the centrality and transverse momentum dependence of the polarization signal.
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32
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Observation of Excess J/ψ Yield at Very Low Transverse Momenta in Au+Au Collisions at sqrt[s_{NN}]=200 GeV and U+U Collisions at sqrt[s_{NN}]=193 GeV. PHYSICAL REVIEW LETTERS 2019; 123:132302. [PMID: 31697545 DOI: 10.1103/physrevlett.123.132302] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 07/21/2019] [Indexed: 06/10/2023]
Abstract
We report on the first measurements of J/ψ production at very low transverse momentum (p_{T}<0.2 GeV/c) in hadronic Au+Au collisions at sqrt[s_{NN}]=200 GeV and U+U collisions at sqrt[s_{NN}]=193 GeV. Remarkably, the inferred nuclear modification factor of J/ψ at midrapidity in Au+Au (U+U) collisions reaches about 24 (52) for p_{T}<0.05 GeV/c in the 60%-80% collision centrality class. This noteworthy enhancement cannot be explained by hadronic production accompanied by cold and hot medium effects. In addition, the dN/dt distribution of J/ψ for the very low p_{T} range is presented for the first time. The distribution is consistent with that expected from the Au nucleus and shows a hint of interference. Comparison of the measurements to theoretical calculations of coherent production shows that the excess yield can be described reasonably well and reveals a partial disruption of coherent production in semicentral collisions, perhaps due to the violent hadronic interactions. Incorporating theoretical calculations, the results strongly suggest that the dramatic enhancement of J/ψ yield observed at extremely low p_{T} originates from coherent photon-nucleus interactions. In particular, coherently produced J/ψ's in violent hadronic collisions may provide a novel probe of the quark-gluon plasma.
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33
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An Endeavor in the Reaction-Based Approach to Fluorescent Probes for Biorelevant Analytes: Challenges and Achievements. Acc Chem Res 2019; 52:2571-2581. [PMID: 31469267 DOI: 10.1021/acs.accounts.9b00314] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The promising features of fluorescence spectroscopy have inspired a quest for fluorescent probes for analysis and monitoring of molecular interactions in biochemical, medical, and environmental sciences. To overcome the competitive supramolecular interactions in aqueous media encountered with conventional molecular-recognition-based probes, the use of reaction-based probes that involve making or breaking of covalent bonds has emerged as a complementary sensing strategy to realize higher selectivity and sensitivity with larger spectroscopic changes. In spite of the enormous efforts, the development of reaction-based fluorescent probes meets with certain challenges in terms of their practical applications, demanding "intelligent design" of probes with an appropriate fluorophore attached to an efficient reactive moiety at the right place. This Account summarizes the results of our efforts made in the development and fine-tuning of reaction-based fluorescent probes toward those goals, classified by the type of analyte (anions, metal cations, and biomolecules) with notes on the challenges and achievements. The reaction-based approach was demonstrated to be powerful for the selective sensing of anions (cyanide and (amino)carboxylates) for the first time, and later it was extended to develop two-photon probes for bisulfite and fluoride ions. The reaction-based approach also enabled selective sensing of noble metal ions such as silver, gold, and palladium along with toxic (methyl)mercury species and paramagnetic copper ions. Furthermore, microscopic imaging and monitoring of biologically relevant species with reaction-based two-photon probes were explored for hydrogen sulfide, hypochlorous acid, formaldehyde, monoamine oxidase enzyme, and ATP.
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Modulation of Kinetic Pathways of Enzyme–Substrate Interaction in a Microfluidic Channel: Nanoscopic Water Dynamics as a Switch. Chemistry 2019; 25:9728-9736. [DOI: 10.1002/chem.201901751] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 05/04/2019] [Indexed: 01/25/2023]
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35
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Azimuthal Harmonics in Small and Large Collision Systems at RHIC Top Energies. PHYSICAL REVIEW LETTERS 2019; 122:172301. [PMID: 31107064 DOI: 10.1103/physrevlett.122.172301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 03/26/2019] [Indexed: 06/09/2023]
Abstract
The first (v_{1}^{fluc}), second (v_{2}), and third (v_{3}) harmonic coefficients of the azimuthal particle distribution at midrapidity are extracted for charged hadrons and studied as a function of transverse momentum (p_{T}) and mean charged particle multiplicity density ⟨N_{ch}⟩ in U+U (sqrt[s_{NN}]=193 GeV), Au+Au, Cu+Au, Cu+Cu, d+Au, and p+Au collisions at sqrt[s_{NN}]=200 GeV with the STAR detector. For the same ⟨N_{ch}⟩, the v_{1}^{fluc} and v_{3} coefficients are observed to be independent of the collision system, while v_{2} exhibits such a scaling only when normalized by the initial-state eccentricity (ϵ_{2}). The data also show that ln(v_{2}/ϵ_{2}) scales linearly with ⟨N_{ch}⟩^{-1/3}. These measurements provide insight into initial-geometry fluctuations and the role of viscous hydrodynamic attenuation on v_{n} from small to large collision systems.
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Unraveling the Role of Monoolein in Fluidity and Dynamical Response of a Mixed Cationic Lipid Bilayer. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:4682-4692. [PMID: 30807692 DOI: 10.1021/acs.langmuir.9b00043] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The maintenance of cell membrane fluidity is of critical importance for various cellular functions. At lower temperatures when membrane fluidity decreases, plants and cyanobacteria react by introducing unsaturation in the lipids, so that the membranes return to a more fluidic state. To probe how introduction of unsaturation leads to reduced membrane fluidity, a model cationic lipid dioctadecyldimethylammonium bromide (DODAB) has been chosen, and the effects of an unsaturated lipid monoolein (MO) on the structural dynamics and phase behavior of DODAB have been monitored by quasielastic neutron scattering and time-resolved fluorescence measurements. In the coagel phase, fluidity of the lipid bilayer increases significantly in the presence of MO relative to pure DODAB vesicles and becomes manifest in significantly enhanced dynamics of the constituent lipids along with faster hydration and orientational relaxation dynamics of a fluorophore. On the contrary, MO restricts both lateral and internal motions of the lipid molecules in the fluid phase (>330 K), which is consistent with relatively slow hydration and orientational relaxation dynamics of the fluorophore embedded in the mixed lipid bilayer. The present study illustrates how incorporation of an unsaturated lipid at lower temperatures (below the phase transition) assists the model lipid (DODAB) in regulating fluidity via enhancement of dynamics of the constituent lipids.
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37
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Probing relaxation dynamics of a cationic lipid based non-viral carrier: a time-resolved fluorescence study. RSC Adv 2019; 9:35549-35558. [PMID: 35528090 PMCID: PMC9074709 DOI: 10.1039/c9ra06824d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 10/18/2019] [Indexed: 01/11/2023] Open
Abstract
Lipid vesicles composed of cationic dioctadecyldimethylammonium bromide (DODAB) and neutral 1-monooleoyl-rac-glycerol (MO) are promising non-viral carriers of nucleic acids for delivery into cells. Among them, higher cell transfection efficiency was displayed by DODAB-rich vesicles than those enriched with MO. Structural relaxation of these mixed lipid vesicles plays a key role in their cell transfection efficiency because structural organization of the DODAB-rich vesicles are different from that of the MO-rich vesicles. Polarization-gated anisotropy in conjunction with picosecond resolved emission transients of a novel fluorophore 6-acetyl-(2-((4-hydroxycyclohexyl)(methyl)amino)naphthalene) (ACYMAN) has been employed to probe relaxation dynamics in pure DODAB vesicles, and in mixed vesicles of DODAB with varying content of MO. Both orientational relaxation of ACYMAN and relaxation dynamics of its local environment are retarded significantly in mixed lipid vesicles with increasing MO content, from a mole fraction (χMO) of 0.2 to that of 0.8 which is consistent with increased rigidity of the MO-rich (χMO > 0.5) vesicles relative to the DODAB-rich (χMO < 0.5) vesicles. Therefore, higher structural rigidity of the MO-rich vesicles (χMO > 0.5) gives rise to their lower cell transfection efficiency than the more flexible DODAB-rich (χMO < 0.5) vesicles as observed in previous in vivo studies (Biochim. Biophys. Acta, Biomembr., 2014, 1838, 2555–2567). Lipid vesicles composed of cationic dioctadecyldimethylammonium bromide (DODAB) and neutral 1-monooleoyl-rac-glycerol (MO) are promising non-viral carriers of nucleic acids for delivery into cells.![]()
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Improved measurement of the longitudinal spin transfer to
Λ
and
Λ¯
hyperons in polarized proton-proton collisions at
s=200 GeV. Int J Clin Exp Med 2018. [DOI: 10.1103/physrevd.98.112009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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39
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Low-p_{T} e^{+}e^{-} Pair Production in Au+Au Collisions at sqrt[s_{NN}]=200 GeV and U+U Collisions at sqrt[s_{NN}]=193 GeV at STAR. PHYSICAL REVIEW LETTERS 2018; 121:132301. [PMID: 30312102 DOI: 10.1103/physrevlett.121.132301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 08/30/2018] [Indexed: 06/08/2023]
Abstract
We report first measurements of e^{+}e^{-} pair production in the mass region 0.4<M_{ee}<2.6 GeV/c^{2} at low transverse momentum (p_{T}<0.15 GeV/c) in noncentral Au+Au collisions at sqrt[s_{NN}]=200 GeV and U+U collisions at sqrt[s_{NN}]=193 GeV. Significant enhancement factors, expressed as ratios of data over known hadronic contributions, are observed in the 40%-80% centrality of these collisions. The excess yields peak distinctly at low p_{T} with a width (sqrt[⟨p_{T}^{2}⟩]) between 40 and 60 MeV/c. The absolute cross section of the excess depends weakly on centrality, while those from a theoretical model calculation incorporating an in-medium broadened ρ spectral function and radiation from a quark gluon plasma or hadronic cocktail contributions increase dramatically with an increasing number of participant nucleons. Model calculations of photon-photon interactions generated by the initial projectile and target nuclei describe the observed excess yields but fail to reproduce the p_{T}^{2} distributions.
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40
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Longitudinal double-spin asymmetries for
π0s
in the forward direction for 510 GeV polarized
pp
collisions. Int J Clin Exp Med 2018. [DOI: 10.1103/physrevd.98.032013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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41
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Fluorescence Analysis: From Sensing to Imaging. JOURNAL OF ANALYTICAL METHODS IN CHEMISTRY 2018; 2018:2654127. [PMID: 30155340 PMCID: PMC6093013 DOI: 10.1155/2018/2654127] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Accepted: 06/24/2018] [Indexed: 06/08/2023]
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42
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Beam Energy Dependence of Jet-Quenching Effects in Au+Au Collisions at sqrt[s_{NN}]=7.7, 11.5, 14.5, 19.6, 27, 39, and 62.4 GeV. PHYSICAL REVIEW LETTERS 2018; 121:032301. [PMID: 30085817 DOI: 10.1103/physrevlett.121.032301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 03/29/2018] [Indexed: 06/08/2023]
Abstract
We report measurements of the nuclear modification factor R_{CP} for charged hadrons as well as identified π^{+(-)}, K^{+(-)}, and p(p[over ¯]) for Au+Au collision energies of sqrt[s_{NN}]=7.7, 11.5, 14.5, 19.6, 27, 39, and 62.4 GeV. We observe a clear high-p_{T} net suppression in central collisions at 62.4 GeV for charged hadrons which evolves smoothly to a large net enhancement at lower energies. This trend is driven by the evolution of the pion spectra but is also very similar for the kaon spectra. While the magnitude of the proton R_{CP} at high p_{T} does depend on the collision energy, neither the proton nor the antiproton R_{CP} at high p_{T} exhibit net suppression at any energy. A study of how the binary collision-scaled high-p_{T} yield evolves with centrality reveals a nonmonotonic shape that is consistent with the idea that jet quenching is increasing faster than the combined phenomena that lead to enhancement.
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Beam-Energy Dependence of Directed Flow of Λ, Λ[over ¯], K^{±}, K_{s}^{0}, and ϕ in Au+Au Collisions. PHYSICAL REVIEW LETTERS 2018; 120:062301. [PMID: 29481217 DOI: 10.1103/physrevlett.120.062301] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Indexed: 06/08/2023]
Abstract
Rapidity-odd directed-flow measurements at midrapidity are presented for Λ, Λ[over ¯], K^{±}, K_{s}^{0}, and ϕ at sqrt[s_{NN}]=7.7, 11.5, 14.5, 19.6, 27, 39, 62.4, and 200 GeV in Au+Au collisions recorded by the Solenoidal Tracker detector at the Relativistic Heavy Ion Collider. These measurements greatly expand the scope of data available to constrain models with differing prescriptions for the equation of state of quantum chromodynamics. Results show good sensitivity for testing a picture where flow is assumed to be imposed before hadron formation and the observed particles are assumed to form via coalescence of constituent quarks. The pattern of departure from a coalescence-inspired sum rule can be a valuable new tool for probing the collision dynamics.
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44
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Two-photon fluorescent probe for hydrogen sulfide based on a red-emitting benzocoumarin dye. Tetrahedron Lett 2018. [DOI: 10.1016/j.tetlet.2017.11.050] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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45
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Two-photon absorbing 8-hydroxy-benzo[g]coumarins with giant Stokes shifts: an environment-insensitive dye platform for probing biomolecules. J Mater Chem B 2018; 6:4446-4452. [DOI: 10.1039/c8tb01144c] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
An 8-hydroxybenzo[g]coumarin derivative with two-photon absorptivity and a large Stokes shift has been highlighted as an environment insensitive dye platform.
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46
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Dijet imbalance measurements in Au+Au and pp collisions at sqrt[s_{NN}]=200 GeV at STAR. PHYSICAL REVIEW LETTERS 2017; 119:062301. [PMID: 28949601 DOI: 10.1103/physrevlett.119.062301] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Indexed: 06/07/2023]
Abstract
We report the first dijet transverse momentum asymmetry measurements from Au+Au and pp collisions at RHIC. The two highest-energy back-to-back jets reconstructed from fragments with transverse momenta above 2 GeV/c display a significantly higher momentum imbalance in heavy-ion collisions than in the pp reference. When reexamined with correlated soft particles included, we observe that these dijets then exhibit a unique new feature-momentum balance is restored to that observed in pp for a jet resolution parameter of R=0.4, while rebalancing is not attained with a smaller value of R=0.2.
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47
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Hypothalamic-Pituitary Axis Regulates Hydrogen Sulfide Production. Cell Metab 2017; 25:1320-1333.e5. [PMID: 28591635 PMCID: PMC5722247 DOI: 10.1016/j.cmet.2017.05.003] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 01/20/2017] [Accepted: 05/11/2017] [Indexed: 01/27/2023]
Abstract
Decreased growth hormone (GH) and thyroid hormone (TH) signaling are associated with longevity and metabolic fitness. The mechanisms underlying these benefits are poorly understood, but may overlap with those of dietary restriction (DR), which imparts similar benefits. Recently we discovered that hydrogen sulfide (H2S) is increased upon DR and plays an essential role in mediating DR benefits across evolutionary boundaries. Here we found increased hepatic H2S production in long-lived mouse strains of reduced GH and/or TH action, and in a cell-autonomous manner upon serum withdrawal in vitro. Negative regulation of hepatic H2S production by GH and TH was additive and occurred via distinct mechanisms, namely direct transcriptional repression of the H2S-producing enzyme cystathionine γ-lyase (CGL) by TH, and substrate-level control of H2S production by GH. Mice lacking CGL failed to downregulate systemic T4 metabolism and circulating IGF-1, revealing an essential role for H2S in the regulation of key longevity-associated hormones.
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Measurement of D^{0} Azimuthal Anisotropy at Midrapidity in Au+Au Collisions at sqrt[s_{NN}]=200 GeV. PHYSICAL REVIEW LETTERS 2017; 118:212301. [PMID: 28598664 DOI: 10.1103/physrevlett.118.212301] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Indexed: 06/07/2023]
Abstract
We report the first measurement of the elliptic anisotropy (v_{2}) of the charm meson D^{0} at midrapidity (|y|<1) in Au+Au collisions at sqrt[s_{NN}]=200 GeV. The measurement was conducted by the STAR experiment at RHIC utilizing a new high-resolution silicon tracker. The measured D^{0} v_{2} in 0%-80% centrality Au+Au collisions can be described by a viscous hydrodynamic calculation for a transverse momentum (p_{T}) of less than 4 GeV/c. The D^{0} v_{2} as a function of transverse kinetic energy (m_{T}-m_{0}, where m_{T}=sqrt[p_{T}^{2}+m_{0}^{2}]) is consistent with that of light mesons in 10%-40% centrality Au+Au collisions. These results suggest that charm quarks have achieved local thermal equilibrium with the medium created in such collisions. Several theoretical models, with the temperature-dependent, dimensionless charm spatial diffusion coefficient (2πTD_{s}) in the range of ∼2-12, are able to simultaneously reproduce our D^{0} v_{2} result and our previously published results for the D^{0} nuclear modification factor.
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Ratiometric Fluorescence Detection of Anthrax Biomarker with EuIII
-EDTA Functionalized Mixed Poly(diacetylene) Liposomes. ASIAN J ORG CHEM 2017. [DOI: 10.1002/ajoc.201700158] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Measurement of the cross section and longitudinal double-spin asymmetry for dijet production in polarized
pp
collisions at
s=200 GeV. Int J Clin Exp Med 2017. [DOI: 10.1103/physrevd.95.071103] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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