37 research outputs found
Indication of Electron Neutrino Appearance from an Accelerator-Produced Off-Axis Muon Neutrino Beam
The T2K experiment observes indications of nu(mu) -> nu(mu) e appearance in data accumulated with 1.43 x 10(20) protons on target. Six events pass all selection criteria at the far detector. In a three-flavor neutrino oscillation scenario with |Delta m(23)(2)| = 2.4 x 10(-3) eV(2), sin(2)2 theta(23) = 1 and sin(2)2 theta(13) = 0, the expected number of such events is 1.5 +/- 0.3(syst). Under this hypothesis, the probability to observe six or more candidate events is 7 x 10(-3), equivalent to 2.5 sigma significance. At 90% C.L., the data are consistent with 0.03(0.04) < sin(2)2 theta(13) < 0.28(0.34) for delta(CP) = 0 and a normal (inverted) hierarchy
Does the Order of Invasive Species Removal Matter? The Case of the Eagle and the Pig
Invasive species are recognized as a primary driver of native species endangerment and their removal is often a key component of a conservation strategy. Removing invasive species is not always a straightforward task, however, especially when they interact with other species in complex ways to negatively influence native species. Because unintended consequences may arise if all invasive species cannot be removed simultaneously, the order of their removal is of paramount importance to ecological restoration. In the mid-1990s, three subspecies of the island fox Urocyon littoralis were driven to near extinction on the northern California Channel Islands owing to heightened predation by golden eagles Aquila chrysaetos. Eagles were lured to the islands by an abundant supply of feral pigs Sus scrofa and through the process of apparent competition pigs indirectly facilitated the decline in foxes. As a consequence, both pigs and eagles had to be removed to recover the critically endangered fox. Complete removal of pigs was problematic: removing pigs first could force eagles to concentrate on the remaining foxes, increasing their probability of extinction. Removing eagles first was difficult: eagles are not easily captured and lethal removal was politically distasteful.Using prey remains collected from eagle nests both before and after the eradication of pigs, we show that one pair of eagles that eluded capture did indeed focus more on foxes. These results support the premise that if the threat of eagle predation had not been mitigated prior to pig removal, fox extinction would have been a more likely outcome.If complete eradication of all interacting invasive species is not possible, the order in which they are removed requires careful consideration. If overlooked, unexpected consequences may result that could impede restoration
T2K neutrino flux prediction
The Tokai-to-Kamioka (T2K) experiment studies neutrino oscillations using an
off-axis muon neutrino beam with a peak energy of about 0.6 GeV that originates
at the J-PARC accelerator facility. Interactions of the neutrinos are observed
at near detectors placed at 280 m from the production target and at the far
detector -- Super-Kamiokande (SK) -- located 295 km away. The flux prediction
is an essential part of the successful prediction of neutrino interaction rates
at the T2K detectors and is an important input to T2K neutrino oscillation and
cross section measurements. A FLUKA and GEANT3 based simulation models the
physical processes involved in the neutrino production, from the interaction of
primary beam protons in the T2K target, to the decay of hadrons and muons that
produce neutrinos. The simulation uses proton beam monitor measurements as
inputs. The modeling of hadronic interactions is re-weighted using thin target
hadron production data, including recent charged pion and kaon measurements
from the NA61/SHINE experiment. For the first T2K analyses the uncertainties on
the flux prediction are evaluated to be below 15% near the flux peak. The
uncertainty on the ratio of the flux predictions at the far and near detectors
is less than 2% near the flux peak
Optimisation of an enzymatic method for beta-galactosidase.
BACKGROUND: The enzyme beta-galactosidase present in the Kupffer cells of the liver has potential as a marker of liver dysfunction prior to transplantation. Spectrophotometric methods have insufficient sensitivity. METHODS: Fluorimetric methods have the required sensitivity and we have optimised such a method in a microtitre plate format to improve its utility. beta-galactosidase acts on the substrate 4-methylumbelliferyl-galactoside (MUG) to produce 4-methylumbelliferone (4-MU), detected fluorimetrically with excitation wavelength 355 nm and emission wavelength 460 nm. RESULTS: Reaction conditions in a citrate-phosphate buffer were optimised to give maximal enzyme activity: pH was optimal at 4.4 (range investigated 3.6-5.0) and substrate concentration at 3.33 mmol/l. A small specimen volume (10 microl) in 80 microl of substrate solution produced adequate fluorescent yield after an incubation period of 30 to 60 min at 37 degrees C. Reaction was terminated by addition of 200 microl of glycine-NaOH, pH 12.8. The assay is linear to 3,000 U/ml. The intra-assay coefficient of variation (CV%) at 50, 502, and 2,012 U/ml was 4.7, 3.1, and 3.4, respectively (n=10). Inter-assay CV% at 51, 496, and 1,986 U/ml was 7.0, 4.0, and 3.9, respectively (n=10). CONCLUSIONS: The assay has greater practical utility and demonstrated significant differences in the perfusate beta-galactosidase between cold-stored and warm-perfused livers in a porcine model of transplantation
Factors Associated with Favorable Drinking Outcome 12 Months After Hospitalization in a Prospective Cohort Study of Inpatients with Unhealthy Alcohol Use
BACKGROUND: Prevalence of unhealthy alcohol use among medical inpatients is high.
OBJECTIVE: To characterize the course and outcomes of unhealthy alcohol use, and factors associated with these outcomes. DESIGN: Prospective cohort study.
PARTICIPANTS: A total of 287 medical inpatients with unhealthy alcohol use.
MAIN MEASURES: At baseline and 12 months later, consumption and alcohol-related consequences were assessed. The outcome of interest was a favorable drinking outcome at 12 months (abstinence or drinking "moderate" amounts without consequences). The independent variables evaluated included demographics, physical/sexual abuse, drug use, depressive symptoms, alcohol dependence, commitment to change (Taking Action), spending time with heavy-drinking friends and receipt of alcohol treatment (after hospitalization). Adjusted regression models were used to evaluate factors associated with a favorable outcome.
KEY RESULTS: Thirty-three percent had a favorable drinking outcome 1 year later. Not spending time with heavy-drinking friends [adjusted odds ratio (AOR) 2.14, 95% CI: 1.14-4.00] and receipt of alcohol treatment [AOR (95% CI): 2.16(1.20-3.87)] were associated with a favorable outcome. Compared to the first quartile (lowest level) of Taking Action, subjects in the second, third and highest quartiles had higher odds of a favorable outcome [AOR (95% CI): 3.65 (1.47, 9.02), 3.39 (1.38, 8.31) and 6.76 (2.74, 16.67)].
CONCLUSIONS: Although most medical inpatients with unhealthy alcohol use continue drinking at-risk amounts and/or have alcohol-related consequences, one third are abstinent or drink "moderate" amounts without consequences 1 year later. Not spending time with heavy-drinking friends, receipt of alcohol treatment and commitment to change are associated with this favorable outcome. This can inform efforts to address unhealthy alcohol use among patients who often do not seek specialty treatment
Radical Surgery in the Presence of Biliary Metallic Stents: Revising the Palliative Scenario
BACKGROUND: The application of endobiliary self-expandable metallic stents (SEMS) is considered the palliative treatment of choice in patients with biliary obstruction in the setting of inoperable malignancies. In the presence of SEMS, however, radical surgery is the only curative option when the resectability status is revised in case of malignancies or for overcoming complications arising from their application in benign conditions that masquerade as inoperable tumours. The aim of our study was to report our surgical experience with patients who underwent an operation due to revision of the initial palliative approach, whilst they had already been treated with biliary SEMS exceeding the hilar bifurcation. METHODS: Three patients with hilar cholangiocarcinoma that was considered inoperable and one patient with IgG4 autoimmune cholangio-pancreatopathy mimicking pancreatic cancer underwent radical resections in the presence of biliary SEMS. RESULTS: After a detailed preoperative workup, two right trisectionectomies, one left extended hepatectomy and a radical extrahepatic biliary resection were performed. All cases demanded resection and reconstruction of the portal vein. R0 resection was achieved in all the malignant cases. Two patients required multiple biliodigestive anastomoses entailing three and seven bile ducts respectively. There was one perioperative death due to postoperative portal vein and hepatic artery thrombosis, whilst two patients developed grade III complications. At follow-up, one patient died at 13 months due to disease recurrence, whilst the remaining two are free of disease or symptoms at 21 and 12 months, respectively. CONCLUSIONS: Revising the initial palliative approach and operating in the setting of biliary metallic stents is extremely demanding and carries significant mortality and morbidity. Radical resection is the only option for offering cure in such complex cases, and this should only be attempted in advanced hepatopancreaticobiliary centres with active involvement in liver transplantation
