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We report a measurement of exclusive J/ψ and ψ(2s) photoproduction in Au+Au ultraperipheral collisions at sqrt[s_{NN}]=200 GeV using the STAR detector. For the first time, (i) the ψ(2s) photoproduction in midrapidity at the Relativistic Heavy-Ion Collider has been experimentally measured; (ii) nuclear suppression factors are measured for both the coherent and incoherent J/ψ production. At average photon-nucleon center-of-mass energy of 25.0 GeV, the coherent and incoherent J/ψ cross sections of Au nuclei are found to be 71±10% and 36±7%, respectively, of that of free protons. The stronger suppression observed in the incoherent production provides a new experimental handle to study the initial-state parton density in heavy nuclei. Data are compared with theoretical models quantitatively.
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BACKGROUND: Surgical treatment is playing an increasingly important role in the management of nasopharyngeal carcinoma (NPC). This consensus focuses on the indications for optimal surgery, and surgical methods in the whole process of treatment for NPC to provide a useful reference to assist these difficult clinical decisions. METHODOLOGY: A thorough review of available literature on NPC and surgery was conducted by the Association for the prevention and treatment of nasopharyngeal carcinoma in China, international exchange and promotion Association for medicine and healthcare, and the Committee on nasopharyngeal cancer of Guangdong provincial anticancer association. A set of questions and a preliminary draft guideline was circulated to a panel of 1096 experienced specialists on this disease for voting on controversial areas and comments. A refined second proposal, based on a summary of the initial voting and different opinions expressed, was recirculated to the experts in two authoritative medical science and technology academic groups in the prevention and treatment of NPC in China for review and reconsideration. RESULTS: The initial round of questions showed variations in clinical practice even among similar specialists, reflecting the lack of high-quality supporting data and resulting difficulties in formulating clinical decisions. Through exchange of comments and iterative revisions, recommendations with high-to-moderate agreement were formulated on general treatment strategies and details of surgery, including indications and surgical approaches. CONCLUSION: By standardizing the surgical indications and practice, we hope not only to improve the surgical outcomes, but also to highlight the key directions of future clinical research in the surgical management of NPC.
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Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/cirurgia , Neoplasias Nasofaríngeas/cirurgia , Neoplasias Nasofaríngeas/patologia , Consenso , Medicina Baseada em Evidências/métodos , ChinaRESUMO
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}â¼750 MeV at sqrt[s_{NN}]=3 GeV is starkly different from those at vanishing µ_{B}â¼24 MeV at sqrt[s_{NN}]=200 GeV and higher collision energies.
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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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Hidrodinâmica , Masculino , Humanos , Anisotropia , Movimento (Física)RESUMO
This corrects the article DOI: 10.1103/PhysRevLett.126.162301.
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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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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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We report on measurements of sequential Ï 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 Ï(1S) and Ï(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 Ï(3S) R_{AA} is 0.17 at a 95% confidence level. This provides experimental evidence that the Ï(3S) is significantly more suppressed than the Ï(1S) at RHIC. The level of suppression for Ï(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 Ï states.
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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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BACKGROUND: Post radiation nasopharyngeal necrosis (PRNN) invading the internal carotid artery (ICA) contributes to the death of 69.2-72.7% of PRNN patients. ICA occlusion is an effective treatment to avoid fatal bleeding, while some patients are intolerant. We present a novel method that allows for these patients without interrupting blood flow through the ICA. METHODOLOGY: This study enrolled patients with PRNN-invaded ICA who were not suitable for ICA occlusion from April 2020 to November 2022. ICA stent pretreatment was performed in the 36 patients and followed the endoscopic nasopharyngectomy (ENPG) or conservative treatment for PRNN. We report the survival outcome and incidence of complications after stent implantation and compare the survival outcomes of ENPG and conservative treatment for PRNN followed by stent implantation. RESULTS: ICA stent pretreatment was performed in the 36 enrolled patients, among which 14 underwent ENPG, and 22 received conservative treatment. 27.8% patients died after a median follow-up of 15 months. The Kaplan-Meier estimates of overall survival were higher in the ENPG group than in the conservative treatment group. Karnofsky performance status (KPS) was significantly higher in the ENPG group than in the non-ENPG group. CONCLUSIONS: The innovative application of ICA stents is a promising treatment to improve outcomes in patients with PRNN invading the ICA who are unsuitable for ICA embolization, especially when followed by endoscopic surgery. However, methods to avoid postoperative cerebral ischemia and nasopharyngeal hemorrhage still require further study.
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BACKGROUND: The surgical treatment of recurrent nasopharyngeal carcinoma (rNPC) involving the internal carotid artery (ICA) is challenging, as the massive bleeding caused by intraoperative rupture of the ICA is life-threatening. We reported that ICA embolization is an effective pretreatment to avoid fatal bleeding, but some patients cannot tolerate the procedure. We used endovascular vascular protection (ICA stents), vascular sacrifice (bypass grafting) and extravascular vascular protection (transcervical external stent placement) of the ICA to provide alternative options for these patients. METHODOLOGYy: This study enrolled patients with rNPC adjacent to or invading the ICA who were unsuitable for ICA embolization from January 2015 to June 2020. ICA pretreatment combined with endoscopic nasopharyngectomy (ENPG) was performed for the 30 patients. We report the survival outcome and incidence of complications after ICA pretreatment. RESULTS: ICA pretreatment was performed for the 30 enrolled patients, among whom 8 underwent endoscopic-assisted transcervical protection of the parapharyngeal ICA combined with ENPG, 6 underwent bypass grafting, and 16 underwent ICA stent implantation followed by ENPG. After pretreatment, at a median follow-up of 43 months (range, 2-80 months), the 3-year locoregional overall survival (OS), progression-free survival (PFS), locoregional recurrence-free survival (LRRFS), and distant metastasis-free survival (DMFS) were 62.9%, 61.3%, 70.2%, and 71.4%, respectively. CONCLUSIONS: ICA pretreatment combined with salvage ENPG enables the feasible and effective resection of rNPC lesions involving the ICA in patients who cannot tolerate ICA embolization. Therefore, this treatment may be an effective method for improving outcomes. Multidisciplinary therapy is needed to reduce operation-related complications.
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With the determination of the whole genome sequence of varicella-zoster virus (VZV) virus, the successful breakthrough of infectious cloning technology of VZV, and the emergence of effective preventive vaccines, which have been proven to be effective and safe, varicella has become a disease preventable by specific immunity. This article will review the genomic structure, epidemiological characteristics, and research application progress of varicella vaccine and herpes zoster vaccine of varicella zoster virus to provide reference for primary prevention of the disease.
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Vacina contra Herpes Zoster , Herpes Zoster , Humanos , Herpesvirus Humano 3/genética , Herpes Zoster/prevenção & controle , Vacina contra Varicela , GenômicaRESUMO
Pancreatic cancer is a malignant tumor of digestive system with poor prognosis,and surgical resection is still the only hope for a radical cure. Although the current consensus and guidelines describe in detail the standard and extended range of lymph node dissection,the selection of specific range of lymph node dissection and its impact on prognosis are still controversial. Current studies have not only proposed some improved extent of lymph node dissection, such as total mesopancreas excision and Heidelberg triangle dissection, but also suggested different extent of lymph node dissection for ventral and dorsal pancreatic head cancer. In addition, the prognosis of pancreatic head cancer in uncinate process and non-uncinate process is different after para-aortic lymph node dissection, which is worthy of further study. Neoadjuvant therapy or conversion therapy provides more surgical opportunities for patients with pancreatic cancer. For these patients, Heidelberg triangle dissection has potential value in improving prognosis. This paper summarizes the exploration and latest progress of standard and extended lymph node dissection, lymph node dissection of specific site of pancreatic head cancer and the extent of lymph node dissection after neoadjuvant/transformation therapy in recent years.
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Excisão de Linfonodo , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/cirurgia , Neoplasias Pancreáticas/patologia , Linfonodos/patologia , Pâncreas/patologia , Prognóstico , Neoplasias PancreáticasRESUMO
Objective: To compare the safety and efficacy of different anticoagulants in patients with indications for anticoagulation after transcatheter aortic valve replacement (TAVR). Methods: This is a retrospective study. Patients who underwent TAVR from April 2016 to February 2022 in Guangdong Provincial People's Hospital and had indications for anticoagulation were included and divided into two groups according to the type of anticoagulants, i.e. non-vitamin K antagonist oral anticoagulant (NOAC) and warfarin, and patients were followed up for 30 days. The primary endpoint was the combination of death, stroke, myocardial infarction, valve thrombosis, intracardiac thrombosis and major bleeding. The incidence of endpoints was compared between two groups, and multivariate logistic regression analysis was applied to adjust the bias of potential confounders. Results: A total of 80 patients were included. Mean age was (74.4±7.1) years, 43 (53.8%) were male. Forty-nine (61.3%) patients used NOAC, 31 used warfarin, and major indication for anticoagulants was atrial fibrillation (76/80, 95.0%). The adjusted risks of the primary endpoint (OR=0.23, 95%CI 0.06-0.94, P=0.040) of NOAC were lower than that of warfarin, mainly driven by a lower risk of major bleeding (OR=0.19, 95%CI 0.04-0.92, P=0.039). Conclusions: The short-term outcome of NOAC is better than that of warfarin in patients with indications for anticoagulation after TAVR. Randomized controlled trials of large sample size with long-term follow-up are needed to further testify this finding.
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Fibrilação Atrial , Acidente Vascular Cerebral , Substituição da Valva Aórtica Transcateter , Humanos , Masculino , Idoso , Idoso de 80 Anos ou mais , Feminino , Anticoagulantes/uso terapêutico , Varfarina/uso terapêutico , Estudos Retrospectivos , Hemorragia , Acidente Vascular Cerebral/epidemiologia , Fibrilação Atrial/tratamento farmacológico , Resultado do Tratamento , Administração OralRESUMO
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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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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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
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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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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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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.