A k-means-based formation algorithm for the delay-aware data collection network structure

2014-2015 > Academic research: refereed > Refereed conference paperAccepted ManuscriptPublishe

High-Contrast OLEDs with High-Efficiency

Peer reviewed: YesNRC publication: Ye

Realization of an Ultra-thin Metasurface to Facilitate Wide Bandwidth, Wide Angle Beam Scanning

© 2018 The Author(s). A wide bandwidth, ultra-thin, metasurface is reported that facilitates wide angle beam scanning. Each unit cell of the metasurface contains a multi-resonant, strongly-coupled unequal arm Jerusalem cross element. This element consists of two bent-arm, orthogonal, capacitively loaded strips. The wide bandwidth of the metasurface is achieved by taking advantage of the strong coupling within and between its multi-resonant elements. A prototype of the proposed metasurface has been fabricated and measured. The design concept has been validated by the measured results. The proposed metasurface is able to alleviate the well-known problem of impedance mismatch caused by mutual coupling when the main beam of an array is scanned. In order to validate the wideband and wide scanning ability of the proposed metasurface, it is integrated with a wideband antenna array as a wide angle impedance matching element. The metasurface-array combination facilitates wide angle scanning over a 6:1 impedance bandwidth without the need for bulky dielectrics or multi-layered structures

Incidence and predictors of upper gastrointestinal bleeding in patients receiving low-dose aspirin for secondary prevention of cardiovascular events in patients with coronary artery disease

Aim: The use of low-dose aspirin to prevent cardiovascular disease events is well established. However, the incidence and predictors of upper gastrointestinal bleeding (UGIB) with its use are unknown. We studied prospectively the incidence and outcome of peptic ulceration in low-dose aspirin users. Methods: A total of 991 patients with coronary artery disease (CAD) on low-dose aspirin were prospectively followed-up for two years for the occurrence and clinical features of first hospitalized episode of UGIB. Results: UGIB had a bimodal presentation with 45% occurring within four months of aspirin initiation and had an overall prevalence of 1.5% per year. There was no UGIB-related death. Hypertension (OR = 4.6, 95%CI 1.5 - 14.7, P = 0.009), history of peptic ulceration (OR = 3.1, 95%CI 1.1 - 9.0, P = 0.039), tertiary education (OR = 3.08, 95%CI 1.1 - 9.0, P = 0.039) and higher lean body mass (P = 0.016) were independent factors associated with UGIB. Use of nitrate did not reduce UGIB. Conclusion: The incidence of UGIB in patients with CAD on long-term low-dose aspirin is low, but is accompanied with significant morbidity. With prolonged use of aspirin, UGIB continues to be a problem for those with risk factors and especially in patients with a history of peptic ulcers, in which UGIB tends to occur early after aspirin therapy. © 2006 The WJG Press. All rights reserved.published_or_final_versio

Paradox of low field enhancement factor for field emission nanodiodes in relation to quantum screening effects

We put forward the quantum screening effect in field emission [FE] nanodiodes, explaining relatively low field enhancement factors due to the increased potential barrier that impedes the electron Fowler-Nordheim tunneling, which is usually observed in nanoscale FE experiments. We illustratively show this effect from the energy band diagram and experimentally verify it by performing the nanomanipulation FE measurement for a single P-silicon nanotip emitter (Φ = 4.94eV), with a scanning tungsten-probe anode (work function, Φ = 4.5eV) that constitutes a 75-nm vacuum nanogap. A macroscopic FE measurement for the arrays of emitters with a 17-μm vacuum microgap was also performed for a fair comparison

Lead Increases Lipopolysaccharide-Induced Liver Injury through Tumor Necrosis Factor-α Overexpression by Monocytes/Macrophages: Role of Protein Kinase C and p42/44 Mitogen-Activated Protein Kinase

Although lead and lipopolysaccharide (LPS), both important environmental pollutants, activate cells through different receptors and participate in distinct upstream signaling pathways, Pb increases the amount of LPS-induced tumor necrosis factor-α (TNF-α). We examined the cells responsible for the excess production of Pb-increased LPS-induced TNF-α and liver injury, and the roles of protein kinase C (PKC) and p42/44 mitogen-activated protein kinase (MAPK) in the induction of TNF-α. Peritoneal injection of Pb alone (100 μmol/kg) or a low dose of LPS (5 mg/kg) did not affect serum TNF-α or liver functions in A/J mice. In contrast, coexposure to these noneffective doses of Pb plus LPS (Pb+LPS) strongly induced TNF-α expression and resulted in profound liver injury. Direct inhibition of TNF-α or functional inactivation of monocytes/macrophages significantly decreased the level of Pb+LPS-induced serum TNF-α and concurrently ameliorated liver injury. Pb+LPS coexposure stimulated the phosphorylation of p42/44 MAPK and the expression of TNF-α in CD14(+) cells of cultured mouse whole blood, peritoneal macrophages, and RAW264.7 cells. Moreover, blocking PKC or MAPK effectively reduced Pb+LPS-induced TNF-α expression and liver injury. In summary, monocytes/macrophages were the cells primarily responsible for producing, through the PKC/MAPK pathway, the excess Pb-increased/LPS-induced TNF-α that caused liver injury

Effect of near‐bed turbulence on chronic detachment of epilithic biofilm: Experimental and modeling approaches.

The biomass dynamics of epilithic biofilm, a collective term for a complex microorganism community that grows on gravel bed rivers, was investigated by coupling experimental and numerical approaches focusing on epilithic biofilm‐flow interactions. The experiment was conducted during 65 days in an artificial rough open‐channel flow, where filtered river water circulated at a constant discharge. To characterize the effect of near‐bed turbulence on the chronic detachment process in the dynamics of epilithic biofilm, local hydrodynamic conditions were measured by laser Doppler anemometry and turbulent boundary layer parameters inferred from double‐averaged quantities. Numerical simulations of the EB biomass dynamics were performed using three different models of chronic detachment based upon three different descriptors for the flow conditions: Discharge Q, friction velocity u*, and roughness Reynolds number k+. Comparisons of numerical simulation results with experimental data revealed chronic detachment to be better simulated by taking the roughness Reynolds number as the external physical variable forcing chronic detachment. Indeed, the loss of epilithic matter through the chronic detachment process is related not only to hydrodynamic conditions, but also to change in bottom roughness. This suggests that changes in the behavior and dimensions of river bed roughness must be considered when checking the dynamics of epilithic biofilm in running waters

The NeuARt II system: a viewing tool for neuroanatomical data based on published neuroanatomical atlases

BACKGROUND: Anatomical studies of neural circuitry describing the basic wiring diagram of the brain produce intrinsically spatial, highly complex data of great value to the neuroscience community. Published neuroanatomical atlases provide a spatial framework for these studies. We have built an informatics framework based on these atlases for the representation of neuroanatomical knowledge. This framework not only captures current methods of anatomical data acquisition and analysis, it allows these studies to be collated, compared and synthesized within a single system. RESULTS: We have developed an atlas-viewing application ('NeuARt II') in the Java language with unique functional properties. These include the ability to use copyrighted atlases as templates within which users may view, save and retrieve data-maps and annotate them with volumetric delineations. NeuARt II also permits users to view multiple levels on multiple atlases at once. Each data-map in this system is simply a stack of vector images with one image per atlas level, so any set of accurate drawings made onto a supported atlas (in vector graphics format) could be uploaded into NeuARt II. Presently the database is populated with a corpus of high-quality neuroanatomical data from the laboratory of Dr Larry Swanson (consisting 64 highly-detailed maps of PHAL tract-tracing experiments, made up of 1039 separate drawings that were published in 27 primary research publications over 17 years). Herein we take selective examples from these data to demonstrate the features of NeuArt II. Our informatics tool permits users to browse, query and compare these maps. The NeuARt II tool operates within a bioinformatics knowledge management platform (called 'NeuroScholar') either as a standalone or a plug-in application. CONCLUSION: Anatomical localization is fundamental to neuroscientific work and atlases provide an easily-understood framework that is widely used by neuroanatomists and non-neuroanatomists alike. NeuARt II, the neuroinformatics tool presented here, provides an accurate and powerful way of representing neuroanatomical data in the context of commonly-used brain atlases for visualization, comparison and analysis. Furthermore, it provides a framework that supports the delivery and manipulation of mapped data either as a standalone system or as a component in a larger knowledge management system

Generalized scaling function from light-cone gauge AdS_5 x S^5 superstring

We revisit the computation of the 2-loop correction to the energy of a folded spinning string in AdS_5 with an angular momentum J in S^5 in the scaling limit log S, J >>1 with J / log S fixed. This correction gives the third term in the strong-coupling expansion of the generalized scaling function. The computation, using the AdS light-cone gauge approach developed in our previous paper, is done by expanding the AdS_5 x S^5 superstring partition function near the generalized null cusp world surface associated to the spinning string solution. The result corrects and extends the previous conformal gauge result of arXiv:0712.2479 and is found to be in complete agreement with the corresponding terms in the generalized scaling function as obtained from the asymptotic Bethe ansatz in arXiv:0805.4615 (and also partially from the quantum O(6) model and the Bethe ansatz data in arXiv:0809.4952). This provides a highly nontrivial strong coupling comparison of the Bethe ansatz proposal with the quantum AdS_5 x S^5 superstring theory, which goes beyond the leading semiclassical term effectively controlled by the underlying algebraic curve. The 2-loop computation we perform involves all the structures in the AdS light-cone gauge superstring action of hep-th/0009171 and thus tests its ultraviolet finiteness and, through the agreement with the Bethe ansatz, its quantum integrability. We do most of the computations for a generalized spinning string solution or the corresponding null cusp surface that involves both the orbital momentum and the winding in a large circle of S^5.Comment: 50 pages, late