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The shear viscosity η of a quark–gluon plasma in equilibrium can be calculated analytically using multiple methods or numerically using the Green–Kubo relation. It has been realized, which we confirm here, that the Chapman–Enskog method agrees well with the Green–Kubo result for both isotropic and anisotropic two-body scatterings. We then apply the Chapman–Enskog method to study the shear viscosity of the parton matter from a multi-phase transport model. In particular, we study the parton matter in the center cell of central and midcentral Au + Au collisions at 200A GeV and Pb + Pb collisions at 2760A GeV, which is assumed to be a plasma in thermal equilibrium but partial chemical equilibrium. As a result of using a constant Debye mass or cross section σ for parton scatterings, the η / s ratio increases with time (as the effective temperature decreases), contrary to the trend preferred by Bayesian analysis of the experimental data or pQCD results that use temperature-dependent Debye masses. At σ = 3 mb that enables the transport model to approximately reproduce the elliptic flow data of the bulk matter, the average η / s of the parton matter in partial equilibrium is found to be very small, between one to two times 1 / (4 π) . [ABSTRACT FROM AUTHOR]

We use the string melting version of a multi-phase transport (AMPT) model to study Cu+Au collisions at s NN = 200 GeV. The rapidity distributions of identified hadrons show asymmetric dependences on rapidity. In addition, elliptic and triangular flows at mid-rapidity from the AMPT model for pions, kaons, and protons agree reasonably with the experimental data up to p T ∼ 1 GeV/c. We then investigate the forward/backward asymmetry of v 2 and v 3 . We find that these anisotropic flows are larger on the Au-going side than the Cu-going side, while the asymmetry tends to go away in very peripheral collisions. We also make predictions on transverse momentum spectra of identified hadrons and longitudinal decorrelations of charged particles, where the average decorrelation of elliptic flow in asymmetric Cu+Au collisions is found to be stronger than that in Au+Au collisions. [ABSTRACT FROM AUTHOR]

Recently, the rapidity-odd directed flow ( v 1 ) of produced hadrons ( K − , ϕ , p ¯ , Λ ¯ , Ξ ¯ + , Ω − , and Ω ¯ + ) has been studied. Several combinations of these produced hadrons, with very small mass differences but differences in the net electric charge ( Δ q ) and net strangeness ( Δ S ) on the two sides, have been considered. A difference in v 1 between the two sides of these combinations ( Δ v 1 ) has been proposed as a consequence of the electromagnetic field produced in relativistic heavy-ion collisions, especially if Δ v 1 increases with Δ q . Our study is performed to understand the effect of the coalescence sum rule (CSR) on Δ v 1 . We point out that the CSR leads to Δ v 1 = c q Δ q + c S Δ S , where the coefficients c q and c S reflect the Δ v 1 of produced quarks. Equivalently, one can write Δ v 1 = c q Δ q + c B Δ B , involving the difference in the net baryon number Δ B , where the CSR gives c B = − 3 c S . We then propose two methods to extract the coefficients for the Δ q and Δ S dependences of Δ v 1 . [ABSTRACT FROM AUTHOR]

In non-central relativistic heavy ion collisions, the created matter possesses a large initial orbital angular momentum. Particles produced in the collisions could be polarized globally in the direction of the orbital angular momentum due to spin–orbit coupling. Recently, the STAR experiment has presented polarization signals for Λ hyperons and possible spin alignment signals for ϕ mesons. Here we discuss the effects of finite coverage on these observables. The results from a multi-phase transport and a toy model both indicate that a pseudorapidity coverage narrower than | η | < ∼ 1 will generate a larger value for the extracted ϕ -meson ρ 00 parameter; thus a finite coverage can lead to an artificial deviation of ρ 00 from 1/3. We also show that a finite η and p T coverage affect the extracted p H parameter for Λ hyperons when the real p H value is non-zero. Therefore proper corrections are necessary to reliably quantify the global polarization with experimental observables. [ABSTRACT FROM AUTHOR]

Flow-like signals including the ridge structure observed in small collision systems that are similar to those in large collision systems have led to questions about the onset of collectivity in nuclear collisions. In this study, we use the string melting version of a multi-phase transport model with or without the sub-nucleon geometry for the proton to study multiparticle cumulants in p + p collisions at 13 TeV. Both versions of the model can produce negative c 2 { 4 } values at high multiplicities. In addition, the dependences of c 2 { 4 } and c 2 { 2 } on the parton cross section σ are found to be strong and non-monotonous, where only an intermediate range of σ values leads to negative c 2 { 4 }. Furthermore, the model with sub-nucleon geometry better describes the multiplicity dependence of c 2 { 4 } , demonstrating the importance of the sub-nucleon geometry for studies of small systems. [ABSTRACT FROM AUTHOR]

It is commonly believed that azimuthal anisotropies in relativistic heavy ion collisions are generated by hydrodynamic evolution of the strongly interacting quark-gluon plasma. Here we use transport models to study how azimuthal anisotropies depend on the number of collisions that each parton suffers. We find that the majority of ν 2 comes from the anisotropic escape of partons, not from the parton collective flow, for semi-central Au+Au collisions at 200A GeV. As expected, the fraction of ν 2 from the anisotropic particle escape is even higher for smaller systems such as d+Au. Our transport model results also confirm that azimuthal anisotropies would be dominated by hydrodynamic flow at unrealistically-high parton cross sections. Our finding thus naturally explains the similarity of azimuthal anisotropies in small and large systems; however, it presents a challenge to the paradigm of anisotropic flow. [ABSTRACT FROM AUTHOR]

Image authentication is a type of technique for the content protection of digital images. This technique is able to detect and locate tampered regions on a digital image. In this paper, two self-embedding image authentication approaches are proposed to involve distinctive singular values. Both of them extract self-characteristics of an image as the crucial authentication information for that image. Subsequently, this information is converted into the two dimensional code format and that codes are then embedded into digital image pixels. With the capability of error correction in two dimensional codes, the extracted authentication data, even being detected with a tamper, still can be completely restored and errorless. As well, it can be utilized to detect whether an image has been tampered with or not. According to experimental results, the proposed approaches are superior to other schemes for images that have been modified to a certain attack extent because the authentication data could be completely extracted in more effective way, and the tampered regions could be identified more accurately. In addition, the proposed approaches utilize these complete self-characteristics to restore tampered regions into their original states. [ABSTRACT FROM AUTHOR]

The rapidity-odd directed flows (v 1) of identified hadrons are expected to follow the coalescence sum rule when the created matter is initially in parton degrees of freedom and then hadronizes through quark coalescence. A recent study has considered the v 1 of produced hadrons that do not contain u or d constituent quarks. It has constructed multiple hadron sets with a small mass difference but given difference in electric charge Δ q and strangeness Δ S between the two sides, where a nonzero and increasing Δ v 1 with Δ q has been proposed to be a consequence of electromagnetic fields. In this study, we examine the consequence of coalescence sum rule on the Δ v 1 of the hadron sets in the absence of electromagnetic fields. We find that in general Δ v 1 ≠ 0 for a hadron set with nonzero Δ q and/or Δ S due to potential v 1 differences between u ¯ and d ¯ and between s and s ¯ quarks. We further propose methods to extract the coefficients for the Δ q - and Δ S -dependences of the direct flow difference, where a nonzero constant term would indicate the breaking of the coalescence sum rule. The extraction methods are then demonstrated with transport model results. [ABSTRACT FROM AUTHOR]

The Petasis reaction using (1S,2R)-1-amino-2-indanol as the substrate and an activator to construct α- and β-butadienyl amines in optically pure forms was realized, which are otherwise difficult to prepare. The reactions feature a metal-free nature, broad substrate scope, complete regioselectivities (γ-selectivity of pinacol homoallenyl- and isoprenylboronates), and high to excellent chirality induction (up to >20 : 1 dr). The favored nucleophilic addition across the Si-face of the imine intermediate was explained using DFT calculations of the six-membered chair-like transition state. [ABSTRACT FROM AUTHOR]

We trace the development of azimuthal anisotropy ( v n , n = 2 , 3 ) via parton–parton collision history in two transport models. The parton v n is studied as a function of the number of collisions of each parton in Au + Au and d + Au collisions at s NN = 200 GeV . It is found that the majority of v n comes from the anisotropic escape probability of partons, with no fundamental difference at low and high transverse momenta. The contribution to v n from hydrodynamic-type collective flow is found to be small. Only when the parton–parton cross-section is set unrealistically large does this contribution start to take over. Our findings challenge the current paradigm emerged from hydrodynamic comparisons to anisotropy data. [ABSTRACT FROM AUTHOR]

Perioperative or postoperative adjuvant chemotherapy based on 5-fluorouracil (5-FU) is a common first-line adjuvant therapy for gastric cancer (GC). However, drug resistance and the side effects of 5-FU have reduced its efficacy. Among these side effects, gastrointestinal (GI) toxicity is one of the most common. Xianglian Pill (XLP) is a Chinese patent medicine that is commonly used for the treatment of diarrhoea. It can reduce inflammation and has a protective effect on the intestinal mucosa. Recent studies have shown that many components of XLP can inhibite tumor cell growth. However, the therapeutic effect of XLP in combination with 5-FU on GC is unclear. To investigate whether the combination of XLP and 5-FU can enhance anti-GC activity while reducing GI toxicity. XLP was administered orally during intraperitoneal injection of 5-FU in GC mice model. Mice were continuously monitored for diarrhea and xenograft tumor growth. After 2 weeks, the mice were sacrificed and serum was collected to determine interleukin-6 levels. Pathological changes, the expression of pro-inflammatory factors and p38 mitogen-activated protein kinase (MAPK) in GI tissue were determined by Western blot analysis. Pathological changes, apoptosis levels and p38 MAPK expression levels in xenograft tissues were also determined. The results showed that XLP could alleviate GI mucosal injury caused by 5-FU, alleviated diarrhea, and inhibited the expression of nuclear factor (NF)-κB and myeloid differentiation primary response-88. Besides, XLP could promote the 5-FU-induced apoptosis of GC cells and enhance the inhibitory effect of 5-FU on tumor xenografts. Further study showed that XLP administration could regulate the expression of p38 MAPK. XLP in combination with 5-FU could alleviate its GI side effects and enhance its inhibitory effect on xenograft tumor. Moreover, these effects were found to be related to the regulation of the p38 MAPK/NF-κB pathway. [Display omitted] • XLP combined with 5-FU could alleviate the diarrhea and reduce the inflammation of gastrointestinal mucosa in GC mice model. • XLP combined with 5-FU could inhibit the growth of xenogaft and promote tumor cell apoptosis in GC mice model. • Those effects were related to the regulation of p38MAPK/NF-κB signaling pathway by XLP. [ABSTRACT FROM AUTHOR]

Rhein, one of the main active components of rhubarb (Dahuang) and Polygonum multiflorum (Heshouwu), has a wide range of effective pharmacological effects. Recently, increasing studies have focused on its potential hepatorenal toxicity, but the cardiotoxicity is unknown. In this study, we found that the IC 50 of rhein to H9c2 cells at 24 h and 48 h were 94.5 and 45.9μmol/L, respectively, with positive correlation of dose-toxicity and time-toxicity. After the treatment of rhein (106, 124 and 132μmol/L), the number of H9c2 cells decreased significantly, and the morphology of H9c2 cells showed atrophy, round shape and wall detachment. Moreover, the proportion of apoptotic cells in H9c2 cells treated with rhein was significantly increased in a dose-dependent manner. And rhein induced S phase arrest of H9c2 cells and inhibited cell proliferation. Rhein up-regulated ROS, LDH levels and low MMP but down-regulated SOD content in H9c2 cells. Additionally, the results showed that the cardiac function LVEF and LVFS of rhein high-medium-low dose groups (350, 175, 87.5 mg/kg) were significantly reduced. And the contents of Ca2+, cTnT, CK and LDH in serum of KM mice were significantly up-regulated by rhein. Furthermore, western blot results suggested that rhein the above effects via promoting Fas-induced apoptosis pathway in vitro and in vivo. In general, rhein may cause cardiotoxicity via Fas-induced apoptosis pathway in vivo and in vitro , which provides reference for the safe use of medicinal plant containing rhein and its preparations. [Display omitted] • The cardiotoxicity of rhein was identified and verified in vivo and in vitro for the first time. • It was proved that rhein could induce the membrane potential and microscopic changes of mitochondria in H9c2 cardiomyocytes. • The cardiotoxic mechanism of rhein was investigated: FAS - induced apoptosis pathway. [ABSTRACT FROM AUTHOR]

We have studied the K* production within a multi-phase transport model (AMPT) for + collisions at to understand the hadronic re-scattering effect on the measured yields of the resonance. The hadronic re-scattering of the K* decay daughter particles (π and K) will alter their momentum distribution thereby making it difficult to reconstruct the K* signal through the invariant mass method. An increased hadronic re-scattering effect thus leads to a decrease in the reconstructed yield of K* in the heavy-ion collisions. Through this simulation study, we argue that a decrease in K*/K ratio with the increase in collision centrality necessarily reflects the hadronic re-scattering effect. Since the re-scattering occurs in the hadronic phase and K* has a lifetime of 4 fm/c, we present a toy model-based discussion on using measured K*/K to put a lower limit on the hadronic phase lifetime in high energy nuclear collisions. [ABSTRACT FROM AUTHOR]

Using a multiphase transport model, we study the production of multistrange (anti)baryons from the hadronic matter formed in relativistic heavy ion collisions. The mechanism we introduce is the strangeness-exchange reactions between antikaons and hyperons for strange particle production and between kaons and antihyperons for strange antiparticle production. We find that these reactions contribute significantly to the production of multistrange baryons and antibaryons in heavy ion collisions at SPS energies, which has been found to be appreciably enhanced. We have also made predictions for multistrange baryon and antibaryon production in heavy ion collisions at RHIC and found a similar enhancement. The (anti)particle mass dependence of inverse slope parameters extracted from their transverse mass spectra in the transport model exhibit similar trend as in the available experimental data at both SPS and RHIC energies. [Copyright &y& Elsevier]

Within a multiphase transport model we study phi meson production in relativistic heavy ion collisions from both superposition of initial multiple proton–proton interactions and the secondary collisions in the produced hadronic matter. The yield of phi mesons is then reconstructed from their decaying product of either the kaon–antikaon pairs or the dimuon pairs. Since the kaon–antikaon pairs at midrapidity with low transverse momenta are predominantly rescattered or absorbed in the hadronic medium, they cannot be used to reconstruct the phi meson and lead thus to a smaller reconstructed phi meson yield than that reconstructed from the dimuon channel. With in-medium mass modifications of kaons and φ mesons, the φ yield from dimuons is further enhanced compared to that from the kaon–antikaon pairs. The model result is compared with the experimental data at the CERN/SPS and RHIC energies and its implications to quark–gluon plasma formation are discussed. [Copyright &y& Elsevier]

It has been a challenge to understand the experimental data on both the nuclear modification factor and elliptic flow of D 0 mesons in p −Pb collisions at LHC energies. In this work, we study these collisions with an improved multi-phase transport model. By including the independent fragmentation and a significant Cronin effect (i.e., transverse momentum broadening) for charm quarks, we provide the first simultaneous description of the D 0 meson R pA and v 2 data at p T ≤ 8 GeV/ c. The model also reasonably describes the D 0 meson p T spectra and the low- p T charged hadron spectra, R pA and v 2. Our results show that both parton interactions and the Cronin effect are important for the D 0 meson R pA , while parton interactions are mostly responsible for the D 0 meson v 2. It is thus essential to include the Cronin effect for the simultaneous description of the D 0 meson R pA and v 2. This work implies that the Cronin effect could also be important for heavy hadrons in large systems. [ABSTRACT FROM AUTHOR]

Context: Liuweibuqi (LWBQ) capsule has been reported to influence symptoms of patients with chronic obstructive pulmonary disease (COPD); however, specific function of LWBQ capsules in COPD with lung-qi deficiency syndrome remains elusive. Objective: This study investigates effect of LWBQ capsules on STAT4/STAT6 and MMP-9/TIMP-1 expression and pulmonary function in stable COPD with lung-qi deficiency syndrome. Materials and methods: Totally, 429 patients diagnosed with stable COPD and lung-qi deficiency syndrome were treated with starch capsules (each time for 9 capsules), or different doses: low (each dose for 8 capsules and 1 LWBQ capsules), medium (each time for 6 capsules and 3 LWBQ capsules), or high (each time for 9 LWBQ capsules) of LWBQ capsules for 30 days, 3 times a day. Forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC% and DLco%pred were evaluated by pulmonary function meter. STAT4/STAT6 and MMP-9/TIMP-1 expression was assessed by RT-qPCR and western blot analysis, and serum concentrations of IL-4, IFN-γ and IL-6 by ELISA. Results: Spearman rank correlation analysis and ROC curve showed that STAT4/STAT6 and MMP-9/TIMP-1 affected pulmonary functions and curative effect of stable COPD with lung-qi deficiency syndrome. After LWBQ capsule treatment, FEV1, FVC, FEV1/FVC% and DLco%pred elevated; STAT4/STAT6, MMP-9/TIMP-1, IFN-γ and IL-6 expression declined whereas IL-4 expression increased (p < 0.05). Logistic regression analysis demonstrated that FEV1/FVC was negatively correlated with STAT4/STAT6 and MMP-9/TIMP-1 expression in COPD patients. Conclusions: LWBQ capsules play a beneficial role in pulmonary function of stable COPD with lung-qi deficiency syndrome via STAT4/STAT6 and MMP-9/TIMP-1. [ABSTRACT FROM AUTHOR]

Abstract In these proceedings we show that the premise of the isobaric Ru 44 96 + 44 96 Ru and Zr 40 96 + 40 96 Zr collisions to search for the chiral magnetic effect (CME) may not hold as originally anticipated due to large uncertainties in the isobaric nuclear structures. We demonstrate this using Woods-Saxon densities and the proton and neutron densities calculated by the density functional theory. Furthermore, a novel method is proposed to gauge background and possible CME contributions in the same system, intrinsically better than the isobaric collisions of two different systems. We illustrate the method with Monte Carlo Glauber and AMPT (A Multi-Phase Transport) simulations. [ABSTRACT FROM AUTHOR]

In this report, we presented a new approach to access a (1,3-butadiene-2-yl)carbinol, (1R,2R)- and (1S,2S)-1-(hydroxymethyl)-1-vinyl-1,2,3,4-tetrahydronaphthalene-2-ols. Starting from commercially available 1,4-diol-2-butyne, a six-step synthesis involving dibromination, Zn-mediated addition reaction of phenylpropyl aldehyde, epoxidation, epoxy-arene cyclization, and resolution with D(+)-Camphor afforded the title compounds. [ABSTRACT FROM AUTHOR]

Predictions for cold nuclear matter effects on charged hadrons, identified light hadrons, quarkonium and heavy flavor hadrons, Drell–Yan dileptons, jets, photons, gauge bosons and top quark pairs produced in p +Pb collisions at s N N = 8.16 TeV are compiled and, where possible, compared to each other. Predictions of the normalized ratios of p +Pb to p + p cross sections are also presented for most of the observables, providing new insights into the expected role of cold nuclear matter effects. In particular, the role of nuclear parton distribution functions on particle production can now be probed over a wider range of phase space than ever before. [ABSTRACT FROM AUTHOR]

Dual C–H thiolation reactions using elemental sulphur remain a challenge. This communication discloses an oxidative radical dual sp2/sp3 C–H thiolation strategy for the coupling of imidazopyridines with ethers or alkanes using elemental sulphur. [ABSTRACT FROM AUTHOR]

Predictions made in Albacete et al. [ Int. J. Mod. Phys. E 22 (2013) 1330007] prior to the LHC Pb run at TeV are compared to currently available data. Some predictions shown here have been updated by including the same experimental cuts as the data. Some additional predictions are also presented, especially for quarkonia, that were provided to the experiments before the data were made public but were too late for the original publication. [ABSTRACT FROM AUTHOR]

The near-side depression in two-proton or two-antiproton azimuthal correlations in pp collisions at s = 7 TeV has been observed experimentally and then qualitatively reproduced in our earlier studies with a multi-phase transport model. In this study, we further investigate the origin of the depression feature in two-baryon correlations in small collision systems. We find that the initial parton-level spatial correlation, a finite expansion in the parton stage, and quark coalescence are important ingredients leading to the near-side depression. In particular, we find that a finite expansion of the parton system leads to a finite space-momentum correlation at hadronization, which then converts the near-side depression in the coordinate space to that in the momentum space. These results suggest that a partonic matter with a finite lifetime is formed in the pp collisions. Further studies are needed to determine whether the partonic matter is near local equilibrium and can thus be called a QGP or far away from local equilibrium. [ABSTRACT FROM AUTHOR]

Double strangeness Ξ − production in Au+Au collisions at 2, 4, and 6 GeV/nucleon incident beam energies is studied with the pure hadron cascade version of a multi-phase transport model. It is found that due to larger nuclear compression, the model with the soft equation of state (EoS) gives larger yields of both single strangeness (K + and Λ + Σ 0) and double strangeness Ξ −. The sensitivity of the double strangeness Ξ − to the EoS is evidently larger than that of K + or Λ + Σ 0 since the phase-space distribution of produced Ξ − is more compact compared to those of the single strangeness. The larger sensitivity of the yields ratio of Ξ − to the EoS from heavy and light systems is kept compared to that of the single strangeness. The study of Ξ − production in relativistic heavy-ion collisions provides an alternative for the ongoing heavy-ion collision program at facilities worldwide for identifying the EoS at high densities, which is relevant to the investigation of the phase boundary and onset of deconfinement of dense nuclear matter. [ABSTRACT FROM AUTHOR]