662 research outputs found
Future Atmospheric Neutrino Detectors
Future experiments focusing on atmospheric neutrino detection are reviewed.
One of the main goals of these experiments is the detection of an unambiguous
oscillation pattern (nu_mu reappearance) to prove the oscillation hypothesis.
Further goals include the discrimination of nu_mu - nu_tau and nu_mu -
nu_sterile oscillations, and the detection of a potential small nu_mu - nu_e
contribution. The search for matter effects in three or more flavour
oscillations can be used to constrain hybrid oscillation models and potentially
measure the sign of delta m^2. The detectors and measurement techniques
proposed to achieve these goals are described, and their physics reach is
discussed.Comment: 9 pages, invited talk at the XIX International Conference on Neutrino
Physics and Astrophysics, Sudbury, Canada, June 16-21, 2000, to appear in
Nucl. Phys. B (Proc. Suppl.
Development of Detonation in Liquid Fuel Spray with Gaseous Oxidizer Preliminary Experiments
Detonation in liquid fuel spray with gaseous oxidize
Efficient Replication of Over 180 Genetic Associations with Self-Reported Medical Data
While the cost and speed of generating genomic data have come down dramatically in recent years, the slow pace of collecting medical data for large cohorts continues to hamper genetic research. Here we evaluate a novel online framework for amassing large amounts of medical information in a recontactable cohort by assessing our ability to replicate genetic associations using these data. Using web-based questionnaires, we gathered self-reported data on 50 medical phenotypes from a generally unselected cohort of over 20,000 genotyped individuals. Of a list of genetic associations curated by NHGRI, we successfully replicated about 75% of the associations that we expected to (based on the number of cases in our cohort and reported odds ratios, and excluding a set of associations with contradictory published evidence). Altogether we replicated over 180 previously reported associations, including many for type 2 diabetes, prostate cancer, cholesterol levels, and multiple sclerosis. We found significant variation across categories of conditions in the percentage of expected associations that we were able to replicate, which may reflect systematic inflation of the effects in some initial reports, or differences across diseases in the likelihood of misdiagnosis or misreport. We also demonstrated that we could improve replication success by taking advantage of our recontactable cohort, offering more in-depth questions to refine self-reported diagnoses. Our data suggests that online collection of self-reported data in a recontactable cohort may be a viable method for both broad and deep phenotyping in large populations
Linfomas primários do estômago: casuística e discussão
Os autores relatam sua experiência com linfomas primários do estômago, revisando os casos assistidos no Hospital Santa Rita da Irmandade da Santa Casa de Misericórdia de Porto Alegre, ao curso de uma década. A despeito de se constituir em patologia de baixa incidência, ajuntaram, por denomada lida, em Serviço de Referência em Câncer, oito casos de linfomas gástricos e um de pseudolinfoma. Exibem os singulares aspectos clínicos, semiológicos e terapêuticos desta neoplasia, discernindo, particularmente, o seguimento daqueles pacientes
Recoilless resonant neutrino capture and basics of neutrino oscillations
It is shown that the experiment on recoilless resonant emission and
absorption of , proposed recently by Raghavan, could have an
important impact on our understanding of the physics of neutrino oscillations.Comment: Additional information in the last chapte
Observation of prompt single muons and of missing energy associated with pairs produced in hadronic interactions
In a study of interactions of 400 GeV protons in a totally absorbing iron calorimeter the authors report two observations indicating the hadronic production of heavy short-lived weakly decaying particles. First they have observed a prompt muon signal in the region .8<p/sub t /<2.5 GeV/c. The rate is comparable in magnitude to the prompt 2 mu rate in the same kinematic region. In addition to detecting mu /sup +/ mu /sup -/ events arising from electromagnetic sources (e.g. rho to mu /sup +/ mu /sup -/, psi to mu /sup +/ mu /sup -/ etc.) they have observed mu /sup +/ mu /sup -/ pairs associated with a significant amount of missing energy indicative of final state neutrinos. Interpreting these data as production of DD pairs followed by single or double muonic decays leads to a model dependent estimate of total production cross-section of order 15 mu b. (14 refs)
Neutrino oscillation parameters from MINOS, ICARUS and OPERA combined
We perform a detailed analysis of the capabilities of the MINOS, ICARUS and
OPERA experiments to measure neutrino oscillation parameters at the atmospheric
scale with their data taken separately and in combination. MINOS will determine
and to within 10% at the 99% C.L. with
10 kton-years of data. While no one experiment will determine with much precision, if its value lies in the combined
sensitivity region of the three experiments, it will be possible to place a
lower bound of O(0.01) at the 95% C.L. on this parameter by combining the data
from the three experiments. The same bound can be placed with a combination of
MINOS and ICARUS data alone.Comment: Version to appear in PR
A Compact Beam Stop for a Rare Kaon Decay Experiment
We describe the development and testing of a novel beam stop for use in a
rare kaon decay experiment at the Brookhaven AGS. The beam stop is located
inside a dipole spectrometer magnet in close proximity to straw drift chambers
and intercepts a high-intensity neutral hadron beam. The design process,
involving both Monte Carlo simulations and beam tests of alternative beam-stop
shielding arrangements, had the goal of minimizing the leakage of particles
from the beam stop and the resulting hit rates in detectors, while preserving
maximum acceptance for events of interest. The beam tests consisted of
measurements of rates in drift chambers, scintilation counter hodoscopes, a gas
threshold Cherenkov counter, and a lead glass array. Measurements were also
made with a set of specialized detectors which were sensitive to low-energy
neutrons, photons, and charged particles. Comparisons are made between these
measurements and a detailed Monte Carlo simulation.Comment: 39 pages, 14 figures, submitted to Nuclear Instruments and Method
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Association of a Workplace Sales Ban on Sugar-Sweetened Beverages With Employee Consumption of Sugar-Sweetened Beverages and Health.
ImportanceReductions in sugar-sweetened beverage (SSB) intake can improve health, but are difficult for individuals to achieve on their own.ObjectivesTo evaluate whether a workplace SSB sales ban was associated with SSB intake and cardiometabolic health among employees and whether a brief motivational intervention provides added benefits to the sales ban.Design, setting, and participantsThis before-after study and additional randomized trial conducted from July 28, 2015, to October 16, 2016, at a Northern California university and hospital assessed SSB intake, anthropometrics, and cardiometabolic biomarkers among 214 full-time English-speaking employees who were frequent SSB consumers (≥360 mL [≥12 fl oz] per day) before and 10 months after implementation of an SSB sales ban in a large workplace, with half the employees randomized to receive a brief motivational intervention targeting SSB reduction.InterventionsThe employer stopped selling SSBs in all workplace venues, and half the sample was randomized to receive a brief motivational intervention and the other half was a control group that did not receive the intervention. This intervention was modeled on standard brief motivational interventions for alcohol used in the workplace that promote health knowledge and goal setting.Main outcomes and measuresOutcomes included changes in SSB intake, Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), and measures of abdominal adiposity. The primary associations tested were the correlation between changes in SSB intake and changes in HOMA-IR.ResultsAmong the 214 study participants, 124 (57.9%) were women, with a mean (SD) age of 41.2 (11.0) years and a baseline mean (SD) body mass index of 29.4 (6.5). They reported a mean daily intake of 1050 mL (35 fl oz) of SSBs at baseline and 540 mL (18 fl oz) at follow-up-a 510-mL (17-fl oz) (48.6%) decrease (P < .001). Reductions in SSB intake correlated with improvements in HOMA-IR (r = 0.16; P = .03). Those not randomized to receive the brief intervention reduced their SSB intake by a mean (SD) of 246.0 (84.0) mL (8.2 [2.8] fl oz), while those also receiving the brief intervention reduced SSB intake by 762.0 (84.0) mL (25.4 [2.8] fl oz). From baseline to follow-up, there were significant reductions in mean (SE) waist circumference (2.1 [2.8] cm; P < .001).Conclusions and relevanceThis study's findings suggest that the workplace sales ban was associated with a reduction in SSB intake and a significant reduction in waist circumference among employees within 10 months. The randomized clinical trial portion of this study found that targeting those at high risk with a brief motivational intervention led to additional improvements. Workplace sales bans may offer a promising new private-sector strategy for reducing the health harms of SSB intake.Trial registrationClinicalTrials.gov identifier: NCT02585336
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