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1.
Phys Rev Lett ; 130(21): 212301, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37295104

RESUMO

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.

2.
Phys Rev Lett ; 130(11): 112301, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-37001106

RESUMO

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.

3.
Phys Rev Lett ; 130(8): 082301, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36898098

RESUMO

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.

5.
Int J Tuberc Lung Dis ; 23(8): 907-912, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31533880

RESUMO

SETTING: Endobronchial ultrasound (EBUS) is now the preferred tool to sample malignant mediastinal lesions. Data on its role in tubercular mediastinal adenopathy are limited.OBJECTIVE: To evaluate the efficacy of EBUS in diagnosing tubercular mediastinal lymphadenopathy and correlate the cytological and microbiological results obtained on aspirate with standard methods (radiology and the tuberculin skin test) suggesting tuberculosis (TB).DESIGN: A prospective study of 125 patients with suspected tubercular mediastinal lymphadenopathy who underwent EBUS-transbronchial needle aspiration. Only patients with a microbiologically confirmed diagnosis or unequivocal clinico-radiological response to anti-TB treatment during follow-up were included.RESULTS: A total of 122 patients showed findings suggesting TB on cytopathology (sensitivity 97.6%), 105 (84%) of whom had microbiological evidence of TB (positive smear/culture or both). Performing staining for acid-fast bacilli on slides prepared during the procedure vs. only on samples submitted in saline significantly improved the yield. Only 92 patients (73.6%) were Mantoux-positive. Cytology was more sensitive than computed tomography in picking up necrosis. Granulomas, with or without necrosis, were equally likely to be microbiologically positive. However, presence of only necrosis in a TB-endemic region invariably points towards TB diagnosis.CONCLUSIONS: EBUS was highly sensitive and specific for diagnosis of mediastinal TB and may be considered the investigation of choice for tubercular mediastinal adenopathy.


Assuntos
Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Linfadenopatia/diagnóstico , Doenças do Mediastino/diagnóstico , Tuberculose dos Linfonodos/diagnóstico , Adolescente , Adulto , Idoso , Antituberculosos/administração & dosagem , Criança , Feminino , Seguimentos , Humanos , Linfadenopatia/tratamento farmacológico , Masculino , Doenças do Mediastino/tratamento farmacológico , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Tuberculose dos Linfonodos/tratamento farmacológico , Adulto Jovem
6.
Br Dent J ; 207(12): 577-82; discussion 574, 2009 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-20019726

RESUMO

OBJECTIVES: To evaluate a pilot specialist practice-based minor oral surgery service. METHODS: Service monitoring data were analysed to evaluate activity, waiting times and outcomes. Patient satisfaction was assessed by a modified version of the Dental Visit Satisfaction Scale. RESULTS: Of 705 treatment appointments, 12.7% were not attended and treatment was not provided in another 11.6%. Mean waiting time from referral receipt to treatment was 6.8 weeks. Treatment provided included surgical removal of third molars, surgical removal of non-third molars and surgical endodontics (26.7%, 60.4% and 4.9% of cases, respectively). Antibiotics were prescribed in 15.0% of treatment cases and 2.3% of treatment cases required appointments for postoperative complications. The response rate for the satisfaction survey was 81%. All participants reported overall satisfaction and strongly agreed/agreed with positive attitudinal statements about the oral surgeon's communication/information giving, technical competence and understanding/acceptance. 77.8% were seen on time and 22.2% within 15 minutes of their appointment. Overall 74.1% felt the standard of service was better than they would expect from a hospital and none felt it was worse. CONCLUSION: The findings of the evaluation suggest that specialist minor oral surgery can be successfully provided in dental practice and is acceptable to patients.


Assuntos
Procedimentos Cirúrgicos Bucais , Odontologia Estatal , Antibacterianos/uso terapêutico , Agendamento de Consultas , Atitude Frente a Saúde , Competência Clínica , Unidade Hospitalar de Odontologia , Relações Dentista-Paciente , Inglaterra , Humanos , Procedimentos Cirúrgicos Menores/estatística & dados numéricos , Dente Molar/cirurgia , Dente Serotino/cirurgia , Procedimentos Cirúrgicos Bucais/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde , Educação de Pacientes como Assunto , Satisfação do Paciente , Projetos Piloto , Complicações Pós-Operatórias , Atenção Primária à Saúde , Encaminhamento e Consulta/estatística & dados numéricos , Tratamento do Canal Radicular , Fatores de Tempo , Extração Dentária/estatística & dados numéricos , Resultado do Tratamento
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