230 research outputs found
Tri-layer polymer actuators with variable dimensions
The ability of conducting polymer actuators to convert electrical energy into mechanical energy is influenced by manyfactors ranging from the actuators physical dimensions to the chemical structure of the conducting polymer. In order toutilise these actuators to their full potential, it is necessary to explore and quantify the effect of such factors on theoverall actuator performance. The aim of this study is to investigate the effect of various geometrical characteristics suchas the actuator width and thickness on the performance of tri-layer polypyrrole (PPy) actuators operating in air, asopposed to their predecessors operating in an appropriate electrolyte. For a constant actuator length, the influence of theactuator width is examined for a uniform thickness geometry. Following this study, the influence of a varied thicknessgeometry is examined for the optimised actuator width. The performance of the actuators is quantified by examination ofthe force output, tip displacement, efficiency as a function of electrical power and mechanical power, and time constantfor each actuator geometry. It was found that a width of 4mm gave the greatest overall performance without curlingalong the actuator length (which occurred with widths above 4mm). This curling phenomenon increased the rigidity ofthe actuator, significantly lowering the displacement for low loads. Furthermore, it was discovered that by focussing ahigher thickness of PPy material in certain regions of the actuators length, greater performances in various domainscould be achieved. The experimental results obtained set the foundation for us to synthesize PPy actuators with anoptimised geometry, allowing their performance to reach full potential for many cutting applications
Energy and operating cost analysis of the smart-scaled flow route directly to adipic acid
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Impaired toll like receptor-7 and 9 induced immune activation in chronic spinal cord injured patients contributes to immune dysfunction
Reduced immune activation or immunosuppression is seen in patients withneurological diseases. Urinary and respiratory infections mainly manifested as septicemia and pneumonia are the most frequent complications following spinal cord injuries and they account for the majority of deaths. The underlying reason of these losses is believed to arise due to impaired immune responses to pathogens. Here, we hypothesized that susceptibility to infections of chronic spinal cord injured (SCI) patients might be due to impairment in recognition of pathogen associated molecular patterns and subsequently declining innate and adaptive immune responses that lead to immune dysfunction. We tested our hypothesis on healthy and chronic SCI patients with a level of injury above T-6. Donor PBMCs were isolated and stimulated with different toll like receptor ligands and T-cell inducers aiming to investigate whether chronic SCI patients display differential immune activation to multiple innate and adaptive immune cell stimulants. We demonstrate that SCI patients' B-cell and plasmacytoid dendritic cells retain their functionality in response to TLR7 and TLR9 ligand stimulation as they secreted similar levels of IL6 and IFNα. The immune dysfunction is not probably due to impaired T-cell function, since neither CD4+ T-cell dependent IFNγ producing cell number nor IL10 producing regulatory T-cells resulted different outcomes in response to PMA-Ionomycin and PHA-LPS stimulation, respectively. We showed that TLR7 dependent IFNγ and IP10 levels and TLR9 mediated APC function reduced substantially in SCI patients compared to healthy subjects. More importantly, IP10 producing monocytes were significantly fewer compared to healthy subjects in response to TLR7 and TLR9 stimulation of SCI PBMCs. When taken together this work implicated that these defects could contribute to persistent complications due to increased susceptibility to infections of chronic SCI patients. © 2017 Gucluler et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Immunostimulatory activity of polysaccharide-poly(I:C) nanoparticles
Cataloged from PDF version of article.Immunostimulatory properties of mushroom derived polysaccharides (PS) as stand-alone agents were tested. Next. PS were nanocomplexed with polyI:C (pIC) to yield stable nanoparticles around 200 nm in size evidenced by atomic force microscopy and dynamic light scattering analyses. PSs were selectively engaged by cells expressing TLR2 and initiated NF kappa B dependent signaling cascade leading to a Th1-biased cytokine/chemokine secretion in addition to bactericidal nitric oxide (NO) production from macrophages. Moreover, cells treated with nanoparticles led to synergistic IL6, production and upregulation of TNF alpha, MIP3 alpha, IFN gamma and IP10 transcript expression. In mice, PS-Ovalbumin-pIC formulation surpassed anti-OVA IgG responses when compared to either PS-OVA or pIC-OVA mediated immunity. Our results revealed that signal transduction initiated both by TLR2 and TLR3 via co-delivery of pIC by PS in nanoparticle depot delivery system is an effective immunization strategy. The present work implicate that the PS and nucleic acid based nanoparticle approach along with protein antigens can be harnessed to prevent infectious diseases. (C) 2011 Elsevier Ltd. All rights reserve
Circulating LL37 targets plasma extracellular vesicles to immune cells and intensifies Behçet's disease severity
Behçet's disease (BD) activity is characterised by sustained, over-exuberant immune activation, yet the underlying mechanisms leading to active BD state are poorly defined. Herein, we show that the human cathelicidin derived antimicrobial peptide LL37 associates with and directs plasma extracellular vesicles (EV) to immune cells, thereby leading to enhanced immune activation aggravating BD pathology. Notably, disease activity was correlated with elevated levels of circulating LL37 and EV plasma concentration. Stimulation of healthy PBMC with active BD patient EVs induced heightened IL1β, IFNα, IL6 and IP10 secretion compared to healthy and inactive BD EVs. Remarkably, when mixed with LL37, healthy plasma-EVs triggered a robust immune activation replicating the pathology inducing properties of BD EVs. The findings of this study could be of clinical interest in the management of BD, implicating LL37/EV association as one of the major contributors of BD pathogenesis. © 2017 The Author(s)
Internal Structure of Einstein-Yang-Mills Black Holes
It is shown that a generic black hole solution of the SU(2)
Einstein-Yang-Mills equations develops a new type of an infinitely oscillating
behavior near the singularity. Only for certain discrete values of the event
horizon radius exceptional solutions exist, possessing an inner structure of
the Schwarzschild or Reissner-Nordstrom type.Comment: 4.5 LaTeX pages, 8 eps figures, uses RevTeX, boxedeps.tex. 4 more
typos fixed, a footnote adde
ASEPS-0 Testbed Interferometer
The ASEPS-O Testbed Interferometer is a long-baseline infrared interferometer optimized for high-accuracy narrow-angle astrometry. It is being constructed by JPL for NASA as a testbed for the future Keck Interferometer to demonstrate the technology for the astrometric detection of exoplanets from the ground. Recent theoretical and experimental work has shown that extremely high accuracy narrow-angle astrometry, at the level of tens of microarcseconds in an hour of integration time, can be achieved with a long-baseline interferometer measuring closely-spaced pairs of stars. A system with performance close to these limits could conduct a comprehensive search for Jupiter- and Saturn-mass planets around stars of all spectral types, and for short-period Uranus-mass planets around nearby M and K stars. The key features of an instrument which can achieve this accuracy are long baselines to minimize atmospheric and photon-noise errors, a dual-star feed to route the light from two separate stars to two beam combiners, cophased operation using an infrared fringe detector to increase sensitivity in order to locate reference stars near a bright target, and laser metrology to monitor systematic errors. The ASEPS-O Testbed Interferometer will incorporate these features, with a nominal baseline of 100 m, 50- cm siderostats, and 40-cm telescopes at the input to the dual- star feeds. The fringe detectors will operate at 2.2 micrometers , using NICMOS-III arrays in a fast-readout mode controlling high-speed laser-monitored delay lines. Development of the interferometer is in progress, with installation at Palomar Mountain planned to begin in 1994
A multidisciplinary approach to address climate-resilience, conservation and comfort in traditional architecture: The PROT3CT example
Traditional dwellings despite their environmental credentials, due to age, previous damage, and residents unable to afford even the limited maintenance allowed by restrictive legal framework, may offer poor thermal performance, which is expected to be further exacerbated by changing climate. More than 70% of Turkey’s built heritage stock is composed of traditional dwellings, which makes this stock able to create a major impact nationally on the building-related energy use, carbon emissions and population wellbeing. This research aims to develop an evidence-based multidisciplinary methodology for cost-effective retrofit of the traditional dwellings in Turkey, to improve energy performance, satisfy user expectations of comfort, and protect heritage value
Embedded Commissioning for Building Design
Building Commissioning has a broad scope that extends to all phases of building delivery. We view commissioning
as a building delivery embedded process that persistently verifies and validates design intent throughout the building lifecycle process.
In the building lifecycle approach, buildings are considered to have cradle-to-grave life spans. They are modeled through a variety
of different developmental phases. In this research project, we intend to build the necessary theory and tools to support the
embedded commissioning process as a co-function of building lifecycle
Fundamental Physics with the Laser Astrometric Test Of Relativity
The Laser Astrometric Test Of Relativity (LATOR) is a joint European-U.S.
Michelson-Morley-type experiment designed to test the pure tensor metric nature
of gravitation - a fundamental postulate of Einstein's theory of general
relativity. By using a combination of independent time-series of highly
accurate gravitational deflection of light in the immediate proximity to the
Sun, along with measurements of the Shapiro time delay on interplanetary scales
(to a precision respectively better than 0.1 picoradians and 1 cm), LATOR will
significantly improve our knowledge of relativistic gravity. The primary
mission objective is to i) measure the key post-Newtonian Eddington parameter
\gamma with accuracy of a part in 10^9. (1-\gamma) is a direct measure for
presence of a new interaction in gravitational theory, and, in its search,
LATOR goes a factor 30,000 beyond the present best result, Cassini's 2003 test.
The mission will also provide: ii) first measurement of gravity's non-linear
effects on light to ~0.01% accuracy; including both the Eddington \beta
parameter and also the spatial metric's 2nd order potential contribution (never
measured before); iii) direct measurement of the solar quadrupole moment J2
(currently unavailable) to accuracy of a part in 200 of its expected size; iv)
direct measurement of the "frame-dragging" effect on light by the Sun's
gravitomagnetic field, to 1% accuracy. LATOR's primary measurement pushes to
unprecedented accuracy the search for cosmologically relevant scalar-tensor
theories of gravity by looking for a remnant scalar field in today's solar
system. We discuss the mission design of this proposed experiment.Comment: 8 pages, 9 figures; invited talk given at the 2005 ESLAB Symposium
"Trends in Space Science and Cosmic Vision 2020," 19-21 April 2005, ESTEC,
Noodrwijk, The Netherland
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