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1.
Phys Rev Lett ; 129(1): 011804, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35841552

RESUMO

We report a search for nonstandard neutrino interactions (NSI) using eight years of TeV-scale atmospheric muon neutrino data from the IceCube Neutrino Observatory. By reconstructing incident energies and zenith angles for atmospheric neutrino events, this analysis presents unified confidence intervals for the NSI parameter ε_{µτ}. The best-fit value is consistent with no NSI at a p value of 25.2%. With a 90% confidence interval of -0.0041≤ε_{µτ}≤0.0031 along the real axis and similar strength in the complex plane, this result is the strongest constraint on any NSI parameter from any oscillation channel to date.

2.
Phys Rev Lett ; 125(14): 141801, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33064514

RESUMO

The results of a 3+1 sterile neutrino search using eight years of data from the IceCube Neutrino Observatory are presented. A total of 305 735 muon neutrino events are analyzed in reconstructed energy-zenith space to test for signatures of a matter-enhanced oscillation that would occur given a sterile neutrino state with a mass-squared differences between 0.01 and 100 eV^{2}. The best-fit point is found to be at sin^{2}(2θ_{24})=0.10 and Δm_{41}^{2}=4.5 eV^{2}, which is consistent with the no sterile neutrino hypothesis with a p value of 8.0%.

3.
Phys Rev Lett ; 124(5): 051103, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32083934

RESUMO

This Letter presents the results from pointlike neutrino source searches using ten years of IceCube data collected between April 6, 2008 and July 10, 2018. We evaluate the significance of an astrophysical signal from a pointlike source looking for an excess of clustered neutrino events with energies typically above ∼1 TeV among the background of atmospheric muons and neutrinos. We perform a full-sky scan, a search within a selected source catalog, a catalog population study, and three stacked Galactic catalog searches. The most significant point in the northern hemisphere from scanning the sky is coincident with the Seyfert II galaxy NGC 1068, which was included in the source catalog search. The excess at the coordinates of NGC 1068 is inconsistent with background expectations at the level of 2.9σ after accounting for statistical trials from the entire catalog. The combination of this result along with excesses observed at the coordinates of three other sources, including TXS 0506+056, suggests that, collectively, correlations with sources in the northern catalog are inconsistent with background at 3.3σ significance. The southern catalog is consistent with background. These results, all based on searches for a cumulative neutrino signal integrated over the 10 years of available data, motivate further study of these and similar sources, including time-dependent analyses, multimessenger correlations, and the possibility of stronger evidence with coming upgrades to the detector.

4.
Transpl Infect Dis ; 11(2): 149-54, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19302281

RESUMO

Strongyloides hyperinfection syndrome has not been reported in lung transplant recipients. We describe the case of a 61-year-old Peruvian man, who received bilateral lung transplants for idiopathic pulmonary fibrosis, and subsequently developed persistent fever with pulmonary infiltrates, ventilator dependence, and pneumothoraces. Bronchoalveolar lavage (BAL) cultures for bacteria, viruses, and fungi were negative, but testing for ova and parasites from BAL fluid revealed Strongyloides stercoralis larvae on day 16 post transplant. He was successfully treated with albendazole and ivermectin, and immunosuppression was reduced. BAL fluid also grew Mycobacterium kansasii, for which he received combination anti-mycobacterial therapy. This case illustrates the importance of screening for parasitic infections before transplantation in the appropriate clinical setting, and demonstrates the utility of direct diagnostic evaluation for parasitic infections in at-risk post-transplant patients with unexplained illnesses.


Assuntos
Anti-Helmínticos/uso terapêutico , Transplante de Pulmão/efeitos adversos , Strongyloides stercoralis/isolamento & purificação , Estrongiloidíase/diagnóstico , Superinfecção/diagnóstico por imagem , Superinfecção/diagnóstico , Albendazol/uso terapêutico , Animais , Líquido da Lavagem Broncoalveolar/parasitologia , Humanos , Ivermectina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Contagem de Ovos de Parasitas , Radiografia , Estrongiloidíase/diagnóstico por imagem , Estrongiloidíase/tratamento farmacológico , Superinfecção/tratamento farmacológico , Tomógrafos Computadorizados
5.
J Postgrad Med ; 53(3): 171-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17699990

RESUMO

CONTEXT: Propofol and midazolam are commonly used sedatives during regional anesthesia in adults. Smaller doses of these drugs are required in older age due to altered pharmacokinetics and pharmacodynamics. AIMS: To study the sedation, side-effects and the costs involved with smaller doses of propofol and midazolam in patients aged above 60 years during spinal anesthesia. SETTINGS AND DESIGN: A randomized single-blind study was conducted in 60 ASA I-II patients aged > or = 60 years undergoing urological surgery under spinal anesthesia. MATERIALS AND METHODS: Sedation was administered after spinal anesthesia using propofol (bolus 0.4 mg.kg -1; infusion 3 mg/kg/hr) or midazolam (bolus 0.02 mg/kg; infusion 0.06 mg.kg -1.h -1) and titrated to achieve a sedation score of 3 on the modified Observer's Assessment of Alertness/Sedation Scale. Perioperative sedation, hemodynamics and respiratory events were monitored. STATISTICAL ANALYSIS: The analysis for parametric data was done using Student's unpaired t test and the incidence data using Chi-square test. RESULTS: The onset (13.0+/-4.2 vs. 18.8+/-4.2 min, P < 0.001) and offset (8.9+/-2.8 vs. 12.5+/-3.5 min, P < 0.001) of sedation were faster and the duration of adequate sedation longer (44.7+/-12.5 vs. 29.8+/-12.9% of total infusion time, P < 0.001) with propofol than midazolam. More patients receiving propofol compared to midazolam had hypotension (16 [50%] vs.4 [14.3%], P= 0.003). Airway obstruction occurred frequently in both the groups. Sedation was significantly more expensive with propofol than midazolam (US$ 9.83 +/- 2.80 vs. US$ 0.33 +/- 0.06, P 0.001). CONCLUSIONS: Propofol provided better titration and adequacy of sedation than midazolam in patients above 60 years of age, but caused hypotension. Lighter sedation is recommended in this age group.


Assuntos
Raquianestesia , Sedação Consciente/métodos , Hipnóticos e Sedativos/administração & dosagem , Midazolam/administração & dosagem , Propofol/administração & dosagem , Idoso , Sedação Consciente/economia , Feminino , Humanos , Hipnóticos e Sedativos/efeitos adversos , Hipotensão/induzido quimicamente , Masculino , Midazolam/efeitos adversos , Pessoa de Meia-Idade , Propofol/efeitos adversos , Método Simples-Cego
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