35 research outputs found

    Autonomous pipeline monitoring and maintenance system: a RFID-based approach

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    Pipeline networks are one of the key infrastructures of our modern life. Proactive monitoring and frequent inspection of pipeline networks are very important for sustaining their safe and efficient functionalities. Existing monitoring and maintenance approaches are costly and inefficient because pipelines can be installed in large scale and in an inaccessible and hazardous environment. To overcome these challenges, we propose a novel Radio Frequency IDentification (RFID)-based Autonomous Maintenance system for Pipelines, called RAMP, which combines robotic, sensing, and RFID technologies for efficient and accurate inspection, corrective reparation, and precise geo-location information. RAMP can provide not only economical and scalable remedy but also safe and customizable solution. RAMP also allows proactive and corrective monitoring and maintenance of pipelines. One prominent advantage of RAMP is that it can be applied to a large variety of pipeline systems including water, sewer, and gas pipelines. Simulation results demonstrate the feasibility and superior performance of RAMP in comparison to the existing pipeline monitoring systems

    Geodesic motions in extraordinary string geometry

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    The geodesic properties of the extraordinary vacuum string solution in (4+1) dimensions are analyzed by using Hamilton-Jacobi method. The geodesic motions show distinct properties from those of the static one. Especially, any freely falling particle can not arrive at the horizon or singularity. There exist stable null circular orbits and bouncing timelike and null geodesics. To get into the horizon {or singularity}, a particle need to follow a non-geodesic trajectory. We also analyze the orbit precession to show that the precession angle has distinct features for each geometry such as naked singularity, black string, and wormhole.Comment: 15 pages, 11 figure

    Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context

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    Long noncoding RNAs (lncRNAs) are commonly dysregulated in tumors, but only a handful are known to play pathophysiological roles in cancer. We inferred lncRNAs that dysregulate cancer pathways, oncogenes, and tumor suppressors (cancer genes) by modeling their effects on the activity of transcription factors, RNA-binding proteins, and microRNAs in 5,185 TCGA tumors and 1,019 ENCODE assays. Our predictions included hundreds of candidate onco- and tumor-suppressor lncRNAs (cancer lncRNAs) whose somatic alterations account for the dysregulation of dozens of cancer genes and pathways in each of 14 tumor contexts. To demonstrate proof of concept, we showed that perturbations targeting OIP5-AS1 (an inferred tumor suppressor) and TUG1 and WT1-AS (inferred onco-lncRNAs) dysregulated cancer genes and altered proliferation of breast and gynecologic cancer cells. Our analysis indicates that, although most lncRNAs are dysregulated in a tumor-specific manner, some, including OIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergistically dysregulate cancer pathways in multiple tumor contexts. Chiu et al. present a pan-cancer analysis of lncRNA regulatory interactions. They suggest that the dysregulation of hundreds of lncRNAs target and alter the expression of cancer genes and pathways in each tumor context. This implies that hundreds of lncRNAs can alter tumor phenotypes in each tumor context

    Healthy eating and survival among elderly men with and without cardiovascularmetabolic diseases

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    Background and aimsThe strength of the associations of dietary scores with cardiovascular disease (CVD) and all-cause mortality in elderly vary considerably between a priori scores. To assess whether healthy eating lowers the risk of CVD and all-cause mortality among elderly men.Methods and resultsThe Zutphen Elderly Study (age 65–84 years) was divided into men with (n = 210) and without (n = 616) cardiovascular-metabolic diseases at baseline in 1985. Diet was assessed with the cross-check dietary history method. We created the “Dutch Healthy Nutrient and Food Score” (DHNaFS) and the “Dutch Undesirable Nutrient and Food Score” (DUNaFS). Associations of the scores with CVD and all-cause mortality were assessed using multivariable Cox regression models. Associations of scores with life years gained used general linear models.During a median follow-up of 10.6 years (IQR 5.8–15.9) 806 participants died, of whom 359 from CVD. In all men, diet scores did not predict death. Among men with cardiovascular-metabolic diseases, DHNaFS was associated with lower CVD (HR: 0.57; 95% CI: 0.35–0.93) and all-cause mortality risk (HR: 0.64; 95% CI: 0.44–0.94) comparing the highest vs. the lowest score tertiles. Men with cardiovascular-metabolic diseases in the highest vs. the lowest tertile of the DHNaFS lived approximately 2.5 years longer. The DHNaFS was not associated with CVD and all-cause mortality in men without cardiovascular-metabolic diseases. The DUNaFS was not associated with any of the outcomes.ConclusionA high quality diet was associated with a 40% lower mortality risk and 2.5 years longer life expectancy in elderly men with, but not without, cardiovascular-metabolic diseases.<br/

    Dynamic electro-optic response of graphene/graphitic flakes in nematic liquid crystals

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    Electric field induced dynamic reorientation phenomenon of graphene/graphitic flakes in homogeneously aligned nematic liquid crystal (NLC) medium has been demonstrated by optical microscopy. The flakes reorient from parallel to perpendicular configuration with respect to boundary plates of confining cells for an applied field strength of as low as tens of millivolt per micrometer. After field removal the reoriented flakes recover to their initial state with the help of relaxation of NLC. Considering flake reorientation phenomenon both in positive and negative dielectric anisotropy NLCs, the reorientation process depends on interfacial Maxwell-Wagner polarization and NLC director reorientation. We propose a phenomenological model based on electric field induced potential energy of graphitic flakes and coupling contribution of positive NLC to generate the rotational kinetic energy for flake reorientation. The model successfully explains the dependence of flake reorientation time over flake shape anisotropy, electric-field strength, and flake area. Using present operating scheme it is possible to generate dark field-off state and bright field-on state, having application potential for electro-optic light modulation devices. ©2013 Optical Society of America.114151sciescopu

    Field-induced stretching and dynamic reorientation of functionalized multiwalled carbon nanotube aggregates in nematic liquid crystals

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    Multiwalled carbon nanotubes (MWCNTs) exhibited distinct electrical stretching behavior in nematic liquid crystals (NLC) depending on nanotube surface state. We found that two different samples prepared by chemical functionalization (f-CNT) and physical grinding (g-CNT) revealed distinct field dependence from each other. The threshold stretching field was lower in the f-CNT aggregates than in g-CNT aggregates. This was attributed to polar functionality induced weakened van der Waals interaction in f-CNTs, which was confirmed in infrared (IR) and Raman spectroscopy. Dynamic reorientation of f-CNTs was observed under polarized optical microscopy where f-CNTs were found to follow orientation of NLC director. Uniformly aligned f-CNTs also exhibited selective light absorption in sufficiently long transient field off-state which could find potential applications in memory and modulator devices as well as the versatile functional composites. © 2015 Elsevier Ltd1441sciescopu
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