Recycled powder as filler admixture in cementitious systems : production and characterization

In concrete production, aggregate represents almost 75% of the materials used. The exploitation of natural sources for this purpose also causes an environmental impact, while deposition of wastes from construction industry pollutes soil and water. The feasibility of recycled coarse aggregate used as component of concrete has been amply proved. Fine recycled aggregate is a by-product derived from the processing of recycled coarse aggregate, but there are some technological difficulties for its use in concrete, because of the high water absorption and powder content. The aim of this study is to propose and analyse the alternative use of milled recycled fine aggregate as mineral admixture. For this purpose, dry recycled fine aggregate was processed in a laboratory ball mill for cement, with the aid of cylpebs. Grinding was carried out for 2:00, 2:45 and 3:30 hours, and the sampling of ground recycled fine aggregate (GRFA) was done after each period. For the three grindings periods, the characterization of GFRA was performed for assessing its suitability as mineral filler. Tests included determinations of contents of material < 45 μm and < 75 μm by wet sieving, density, particle size distribution by laser diffraction, chemical composition and Blaine specific surface. Additionally, water demand for standard consistency paste with ordinary Portland cement (OPC) was prepared as reference, and also determined for pastes with replacement of 15% and 30% of cement by GRFA for each grinding period. Also, setting times and strength were measured. Results showed limited filler effect from GRFA when incorporated in cementitious materials, with the consideration of the grinding period as an important factor. Thus, further feasibility studies are necessary in order to investigate different potential applications of this ground material

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

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

Differential Effects of Lipid-lowering Drugs in Modulating Morphology of Cholesterol Particles.

Treatment of dyslipidemia patients with lipid-lowering drugs leads to a significant reduction in low-density lipoproteins (LDL) level and a low to moderate level of increase in high-density lipoprotein (HDL) cholesterol in plasma. However, a possible role of these drugs in altering morphology and distribution of cholesterol particles is poorly understood. Here, we describe the in vitro evaluation of lipid-lowering drug effects in modulating morphological features of cholesterol particles using the plaque array method in combination with imaging flow cytometry. Image analyses of the cholesterol particles indicated that lovastatin, simvastatin, ezetimibe, and atorvastatin induce the formation of both globular and linear strand-shaped particles, whereas niacin, fibrates, fluvastatin, and rosuvastatin induce the formation of only globular-shaped particles. Next, purified very low-density lipoprotein (VLDL) and LDL particles incubated with these drugs showed changes in the morphology and image texture of cholesterol particles subpopulations. Furthermore, screening of 50 serum samples revealed the presence of a higher level of linear shaped HDL cholesterol particles in subjects with dyslipidemia (mean of 18.3%) compared to the age-matched normal (mean of 11.1%) samples. We also observed considerable variations in lipid-lowering drug effects on reducing linear shaped LDL and HDL cholesterol particles formation in serum samples. These findings indicate that lipid-lowering drugs, in addition to their cell-mediated hypolipidemic effects, may directly modulate morphology of cholesterol particles by a non-enzymatic mechanism of action. The outcomes of these results have potential to inform diagnosis of atherosclerosis and predict optimal lipid-lowering therapy

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

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

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

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

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

Inference-Based Quantum Sensing

In a standard Quantum Sensing (QS) task one aims at estimating an unknown parameter $\theta$, encoded into an $n$-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 $\mathcal{R}(\theta)$ (i.e., changes in the measurement outcomes). For simple cases the form of $\mathcal{R}(\theta)$ 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, $\mathcal{R}(\theta)$ can be fully characterized by only measuring the system response at $2n+1$ 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 $\delta$, if one measures the system response with a number of shots that scales only as $\Omega(\log^3(n)/\delta^2)$. 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