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Fritz, Thibaud M. (author), Dedoussi, I.C. (author), Eastham, Sebastian D. (author), Speth, Raymond L. (author), Henze, Daven K. (author), Barrett, Steven R.H. (author)
Depletion of stratospheric ozone, and the associated increase in population exposure to UV radiation, is an environmental consequence of high-altitude, supersonic aviation. Assessments of the impacts of emissions from subsonic aircraft – which fly at lower altitudes – have instead shown that they produce a net increase, rather than decrease,...
journal article 2022
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Gijsen, F.J.H. (author), Vis, Bas (author), Barrett, Hilary E. (author), Zadpoor, A.A. (author), Verhagen, Hence J. (author), Bos, Daniel (author), van der Steen, A.F.W. (author), Akyildiz, A.C. (author)
Objective: Atherosclerotic plaque rupture in carotid arteries is a major source of cerebrovascular events. Calcifications are highly prevalent in carotid plaques, but their role in plaque rupture remains poorly understood. This work studied the morphometric features of calcifications in carotid plaques and their effect on the stress...
journal article 2021
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Van der Heiden, K. (author), Barrett, H. E. (author), van Gaalen, K.C. (author), Krenning, B. J. (author), Beekman, F.J. (author), Verhagen, H. J.M. (author), Norenberg, J. P. (author), de Jong, M. (author), Gijsen, F.J.H. (author)
Background: Calcification and inflammation are atherosclerotic plaque compositional biomarkers that have both been linked to stroke risk. The aim of this study was to evaluate their co-existing prevalence in human carotid plaques with respect to plaque phenotype to determine the value of hybrid imaging for the detection of these biomarkers....
journal article 2021
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Barrett, John (author), Gavin, Kenneth (author), Doyle, Tom (author)
Tidal-stream (tidal) energy is a renewable form of energy produced by harnessing the kinetic energy of marine currents created by the rise and fall of the tides and converting it into electricity. To-date, tidal energy development remains largely in the demonstration stage and the development community has not rallied behind any one foundation...
conference paper 2020
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Barrett, Hilary E. (author), Meester, Eric J. (author), van Gaalen, Kim (author), van der Heiden, Kim (author), Krenning, Boudewijn J. (author), Beekman, F.J. (author), Verhagen, H. J. (author), de Jong, M. (author), Gijsen, F.J.H. (author)
Purpose: Atherosclerotic plaque development and progression signifies a complex inflammatory disease mediated by a multitude of proinflammatory leukocyte subsets. Using single photon emission computed tomography (SPECT) coupled with computed tomography (CT), this study tested a new dual-isotope acquisition protocol to assess each radiotracer...
journal article 2020
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Henneman, Lucas R. F. (author), Dedoussi, I.C. (author), Casey, Joan A. (author), Choirat, Christine (author), Barrett, Steven R. H. (author), Zigler, Corwin M. (author)
Expanded use of reduced complexity approaches in epidemiology and environmental justice investigations motivates detailed evaluation of these modeling approaches. Chemical transport models (CTMs) remain the most complete representation of atmospheric processes but are limited in applications that require large numbers of runs, such as those that...
journal article 2020
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Dedoussi, I.C. (author), Allroggen, Florian (author), Flanagan, Robert (author), Hansen, Tyler (author), Taylor, Brandon (author), Barrett, Steven R. H. (author), Boyce, James K. (author)
Fossil fuel combustion releases carbon dioxide into the atmosphere along with co-pollutants such as sulfur dioxide, nitrogen oxides, and others. These emissions result in environmental externalities primarily in terms of climate and air quality. Here we quantify the cost of co-pollutant emissions per ton of CO <sub>2</sub> emissions from US...
journal article 2019
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Kozijn, A. E. (author), Tartjiono, M. T. (author), Ravipati, S. (author), van der Ham, F. (author), Barrett, D. A. (author), Mastbergen, S. C. (author), Korthagen, N. M. (author), Lafeber, F. P.J.G. (author), Zuurmond, A. M. (author), Bobeldijk, I. (author), Weinans, Harrie (author), Stoop, R. (author)
Objective: C-reactive protein (CRP) levels can be elevated in osteoarthritis (OA) patients. In addition to indicating systemic inflammation, it is suggested that CRP itself can play a role in OA development. Obesity and metabolic syndrome are important risk factors for OA and also induce elevated CRP levels. Here we evaluated in a human CRP ...
journal article 2019
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de Visser, H.M. (author), Mastbergen, S. C. (author), Ravipati, S. (author), Welsing, P. M.J. (author), Pinto, F.C. (author), Lafeber, F.P.J.G. (author), Chapman, V. (author), Barrett, D. A. (author), Weinans, Harrie (author)
Objective Bioactive oxidised lipids (oxylipins) are important signalling mediators, capable of modulating the inflammatory state of the joint and anticipated to be of importance in joint homeostasis and status of osteoarthritis. The aim of this study was to quantify oxylipin levels in plasma and synovial fluid from rats with experimentally...
journal article 2018
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Vos, R. (author), Scheepstra, J. (author), Barrett, R. (author)
The paper begins with a brief historical overview of pressure adaptive materials and structures. By examining avian anatomy, it is seen that pressure-adaptive structures have been used successfully in the Natural world to hold structural positions for extended periods of time and yet allow for dynamic shape changes from one flight state to the...
conference paper 2011
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Scheepstra, J. (author), Vos, R. (author), Barrett, R. (author)
A new method for designing a morphing Fowler flap based on pressure-adaptive honeycomb is detailed. Pressure adaptive honeycomb has been shown to be able to induce gross camber deformations in airfoil sections, such as a flap. However, due to the large amount of design variables the integration of the honeycomb as a distributed actuator in a...
conference paper 2011
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Vos, R. (author), Barrett, R. (author)
A new type of adaptive structure is presented that relies on pressurized honeycomb cells that extent a significant length with respect to the plane of the hexagons. By varying the pressure inside each of the cells, the stiffness can be altered. A variable stiffness in combination with an externally applied force field results in a fully embedded...
conference paper 2010
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Vos, R. (author), Barrett, R. (author)
A new type of adaptive structure is presented that relies on a pressure derential to perform gross structural deformations. This structure relies on highly compliant honey-comb cells that can be pressurized externally or can rely on a pressure differential that exists at elevated altitudes. By pressurizing this honeycomb, its stiffness can be...
conference paper 2010
document
Vos, R. (author), Barrett, R. (author)
A new type of adaptive structure is presented that relies on pressurized honeycomb cells that extent a significant length with respect to the plane of the hexagons. By varying the pressure inside each of the cells, the stiffness can be altered. A variable stiffness in combination with an externally applied force field results in a fully embedded...
conference paper 2010
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Groen, M. (author), Van Schravendijk, M. (author), Barrett, R. (author), Vos, R. (author)
The dynamic response of a new class of flight control actuators that rely on post-buckled recompressed (PBP) piezoelectric elements is investigated. While past research has proven that PBP actuators are capable of generating deflections three times higher than conventional bimorph actuators, this paper quantifies the work output and power...
conference paper 2009
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Barrett, R. (author), Vos, R. (author), De Breuker, R. (author)
This paper describes a new class of flight control actuators using Post-Buckled Precompressed (PBP) piezoelectric elements to provide much improved actuator performance. These PBP actuator elements are modeled using basic large deflection Euler-beam estimations accounting for laminated plate effects. The deflection estimations are then coupled...
conference paper 2007
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Vos, R. (author), Barrett, R. (author), De Breuker, R. (author), Tiso, P. (author)
journal article 2007
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Barrett, R.H. (author), Tiso, P. (author)
Actuator comprising: a) a support beam (10) b) a first means (20, 30, 40) for placing said support beam in compression (50) without causing flexure of said support beam; c) a first layer of material (90) adhered to a first surface of said support beam and d) a second means (120, 130) for causing movement of said first layer of material to cause...
patent 2006
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Vos, R. (author), Barrett, R. (author), Krakers, L. (author), Van Tooren, M. (author)
This paper presents the use of a new class of flight control actuators employing Post-Buckled Precompressed (PBP) piezoelectric elements in morphing wing Uninhabited Aerial Vehicles (UAVs). The new actuator relieson axial compression to amplify deflections and control forces simultaneously. Two designs employing morphingwing panels based on PBP...
conference paper 2006
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Barrett, R. (author), Melkert, J. (author)
Visual signature suppression (VSS) methods for several classes of aircraft from WWII on are examined and historically summarized. This study shows that for some classes of uninhabited aerial vehicles (UAVs), primary mission threats do not stem from infrared or radar signatures, but from the amount that an aircraft visually stands out against the...
conference paper 2005
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