440 research outputs found

    Ground-simulation investigations of VTOL airworthiness criteria for terminal-area operations

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    Several ground-based simulation experiments undertaken to investigate concerns related to tilt-rotor aircraft airworthiness were conducted. The experiments were conducted on the National Aeronautics and Space Administration (NASA) Ames Research Center's Vertical Motion Simulator, which permits simulation of a wide variety of aircraft with a high degree of fidelity of motion cueing. Variations in conversion/deceleration profile, type of augmentation or automation, level of display assistance, and meteorological conditions were considered in the course of the experiments. Certification pilots from the Federal Aviation Administration (FAA) and the Civil Aviation Authority (CAA) participated, in addition to NASA research pilots. The setup of these experiments on the simulator is summarized, and some of the results highlighted

    Use of Alternative Tobacco Products in Multiethnic Youth from Jujuy, Argentina

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    This study examines alternative tobacco use among Latin American youth. A self-administered survey in a random sample of 27 schools was administered in 2004 in Jujuy, Argentina (N = 3218). Prevalence of alternative tobacco product use was 24.1%; 15.3% of youth used hand-rolled cigarettes, 7.8% smoked cigars, 2.3% chewed tobacco leaf and 1.6% smoked pipe. Among youth who never smoked manufactured cigarettes, alternative product use was rare (2.9%), except for chewing tobacco (22%). In multivariate logistic regression boys were more likely than girls to smoke pipe (OR = 3.1; 95% CI 1.1–8.7); indigenous language was associated with smoking hand-rolled cigarettes (OR = 1.4; 95% CI-1.1–1.9) and pipe (OR = 2.2; 95% CI 1.5–3.4). Working in tobacco sales was a risk factor for chewing tobacco (OR = 2.9; 95% CI: 1.7–4.9) and smoking hand-rolled cigarettes (OR = 1.4; 95% CI 1.1–1.8). Having friends who smoked was associated with chewing tobacco (OR = 1.8; 95% CI 1.0–3.2) and with smoking cigars (OR = 2.1; 95% CI 1.5–2.9). Current drinking and thrill-seeking orientation were associated with cigars and pipe smoking. Findings highlight the importance of surveillance of alternative tobacco products use and availability among youth and for addressing identified risk factors

    Functionalized up conversion rare earth nanoparticles for bio imaging of cancer cells

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    In recent yearsupconversion nanoparticles (UCNPs)have being investigated due to their potential applications in biomedicine such as fluorescent biolabels, among many others. The luminescence of this kind of NP's are effectively activatedby near infrared radiation (NIR) and upconvertto luminescence in the visible region. Besides, their luminescence is not faded as compared with organic dyes and fluorescent proteins. In this study, UCNPs made of Y2O3:Yb3+, Er3+ (1%, 10% mol) and Gd2O3:Yb3+, Er3+ (1%, 10% mol) were functionalized with aminosilanes and folic acid (UCNP-NH2-FA) and characterized with transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and luminescence measurements. Moreover, cytotoxicity was analyzed via colorimetric assays MTT (methy-134 thiazolyltetrazolium) in two cancer cell lines: cervical adenocarcinoma cells (HeLa) and breast cancer cells MB-MDA-231. It is found that the functionalized UCNPs were non-cytotoxic in all cancer cell lines. Confocal images revealed that UCNP-NH2-FA conjugates as a target to attract cells with overexpressed folate receptor (FR). The UCNPs offer a great potential to be used as bio labels because their fluorescence was clearly localized into cell cytoplasm

    Inference-Based Quantum Sensing

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    In a standard Quantum Sensing (QS) task one aims at estimating an unknown parameter θ\theta, encoded into an nn-qubit probe state, via measurements of the system. The success of this task hinges on the ability to correlate changes in the parameter to changes in the system response R(θ)\mathcal{R}(\theta) (i.e., changes in the measurement outcomes). For simple cases the form of R(θ)\mathcal{R}(\theta) is known, but the same cannot be said for realistic scenarios, as no general closed-form expression exists. In this work we present an inference-based scheme for QS. We show that, for a general class of unitary families of encoding, R(θ)\mathcal{R}(\theta) can be fully characterized by only measuring the system response at 2n+12n+1 parameters. In turn, this allows us to infer the value of an unknown parameter given the measured response, as well as to determine the sensitivity of the sensing scheme, which characterizes its overall performance. We show that inference error is, with high probability, smaller than δ\delta, if one measures the system response with a number of shots that scales only as Ω(log3(n)/δ2)\Omega(\log^3(n)/\delta^2). Furthermore, the framework presented can be broadly applied as it remains valid for arbitrary probe states and measurement schemes, and, even holds in the presence of quantum noise. We also discuss how to extend our results beyond unitary families. Finally, to showcase our method we implement it for a QS task on real quantum hardware, and in numerical simulations.Comment: 5+10 pages, 3+5 figure

    Country and gender differences in the association between violence and cigarette smoking among youth

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    Background: Exposure to violence in youth may be associated with substance use and other adverse health effects. This study examined cigarette smoking in two middle-income areas with different levels and types of exposure to violence. Methods: Association of exposure to verbal and physical violence with cigarette smoking in the West Bank oPt (2008) and in Jujuy Argentina (2006) was examined using cross-sectional surveys of 14 to 17-year old youth in 7th to 10th grade using probabilistic sampling. Results: Violence exposure rates were more than double for Palestinian girls (99.6% vs. 41.2%) and boys (98.7% vs. 41.1%) compared with Argentinians. The rate of current cigarette smoking was significantly higher among Argentinian girls compared with Palestinian girls (33.1% vs. 7.1%, p < 0.001). Exposure to verbal violence from family and to physical violence increased the odds of current cigarette smoking, respectively, among Argentinian girls (aOR = 1.3, 95% CI = 1.0–1.7; aOR = 2.5, 95%CI = 1.7–3.8), Palestinian girls (aOR 2.2, 95%CI = 1.1–2.4; aOR = 2.0, 95%CI = 1.1–3.6) and Argentinian boys (aOR = 1.5, 95%CI = 1.1–2.0; aOR = 2.2, 95%CI = 1.6–3.0), but not among Palestinian boys. Conclusion: Findings highlight the importance of producing context and gender specific evidence from exposure to violence, to inform and increase the impact of targeted smoking prevention strategies.Fil: Abu Rmeileh, Niveen M. E.. Birzeit University; Palestina (ANP)Fil: Alderete, Ethel del Carmen. Universidad Nacional de Jujuy; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Unidad Ejecutora en Ciencias Sociales Regionales y Humanidades. Universidad Nacional de Jujuy. Unidad Ejecutora en Ciencias Sociales Regionales y Humanidades; Argentina. Instituto de Ciencia y Tecnología Regional; ArgentinaFil: Husseini, Abdullatif. Birzeit University; Palestina (ANP)Fil: Livaudais Toman, Jennifer. University of California; Estados UnidosFil: Pérez Stable, Eliseo J.. National Institutes of Health; Estados Unido

    Youth working in tobacco farming: effects on smoking behavior and association with health status

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    Background: Cultivation of tobacco raises concerns about detrimental health and social consequences for youth, but tobacco producing countries only highlight economic benefits. We compared sociodemographic and health-related characteristics of school-age youth who worked and did not work in tobacco farming and assessed the effects on smoking behavior and health at 1 year. Methods: We used existing data collected in the province of Jujuy, Argentina where 3188 youth 13 to 17 years of age from a random middle school sample responded to longitudinal questionnaires in 2005 and 2006. Multivariate logistic regression models predicted association of tobacco farming work with health status and smoking behavior at 1 year. Results: 22.8% of youth in the tobacco growing areas of the province were involved in tobacco farming. The mean age of initiation to tobacco farming was 12.6 years. Youth working in farming had higher rates of fair or poor versus good or excellent self-perceived health (30.3% vs. 19.0%), having a serious injury (48.5% vs. 38.5%), being injured accidentally by someone else (7.5% vs. 4.6%), being assaulted (5.5% vs. 2.6%), and being poisoned by exposure to chemicals (2.5% vs. 0.7%). Youth working in tobacco farming also had higher prevalence of ever (67.9% vs. 55.2%), current (48.0% vs. 32.6%) and established smoking (17.8% vs. 9.9%). In multivariate logistic regression models tobacco farming in 2005 was associated with significant increased reporting of serious injury (OR = 1.4; 95%CI 1.1-2.0), accidental injury by someone else (OR = 1.5; 95% 1.0-2.1), assault (OR = 2.2; 95% CI 1.3-3.8), and poisoning by exposure to chemicals (OR = 2.5; 95% CI 1.2-5.4). Tobacco farming in 2005 predicted established smoking 1 year later (OR = 1.5; 95% CI 1.1-2.0). Conclusion: Youth who work in tobacco faming face a challenging burden of adversities that increase their vulnerability. Risk assessments should guide public policies to protect underage youth working in tobacco farming. (298 words).Fil: Alderete, Ethel del Carmen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Unidad Ejecutora en Ciencias Sociales Regionales y Humanidades. Universidad Nacional de Jujuy. Unidad Ejecutora en Ciencias Sociales Regionales y Humanidades; ArgentinaFil: Livaudais Toman, Jennifer. University of California; Estados UnidosFil: Kaplan, Celia. University of California; Estados UnidosFil: Gregorich, Steven E.. University of California; Estados UnidosFil: Mejía, Raúl. Centro de Estudios de Estado y Sociedad; ArgentinaFil: Pérez Stable, Eliseo J.. National Institutes of Health; Estados Unido
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