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Institution

Wright-Patterson Air Force Base

OtherWright-Patterson AFB, Ohio, United States
About: Wright-Patterson Air Force Base is a other organization based out in Wright-Patterson AFB, Ohio, United States. It is known for research contribution in the topics: Laser & Mach number. The organization has 5817 authors who have published 9157 publications receiving 292559 citations. The organization is also known as: Wright-Patterson AFB & FFO.


Papers
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Journal ArticleDOI
TL;DR: The field of toxicology reviewed here represents an interface between pharmacokinetic research and studies on basic mechanisms of toxic action, and entails utilization of quantitative concepts to better understand the physiological and biochemical controls which regulate the expression of the toxicity of various chemicals.
Abstract: Metabolism plays a central role in regulating the toxicity of a variety of chemicals. Relatively innocuous substances can be converted to highly toxic metabolites. Conversely, toxic substances can be biotransformed to less harmful metabolites or be excreted, thus limiting their duration of biological action. Virtually all metabolism and many excretory processes utilize specific binding proteins, i.e., enzymes and carrier proteins. These metabolic and carrier-mediated excretory clearance pathways are capacity-limited, becoming saturated at sufficiently high substrate concentrations. Saturable metabolic clearance processes lead to dose-dependent pharmacokinetics for many chemicals. When dose-dependent pharmacokinetics prevail, internally significant parameters, such as area under the curve for concentration of toxicant at active sites and the amount of metabolite formed during inhalation exposure, are not linearly related to externally significant parameters such as administered dose or inspired concentration. Dose-response curves should relate observed effects to some internally significant parameter. Toxic response should often be indexed to area under the curve relationships or total amount metabolized, instead of dose or inspired concentration. The former parameters are complexly related to the latter. The nature of the relationship depends on the kinetic constants for metabolic and excretory clearance. Pharmacokinetic analyses of dose-dependent clearance mechanisms provide an understanding of how one transforms externally significant parameters to internally significant parameters under various exposure conditions. Consideration of metabolic clearance at the organ level illuminates the importance of physiological factors, showing unequivocally that blood flow may be rate-limiting for metabolism under many exposure conditions. Recognition of the potential for this behavior is essential to the proper design and evaluation of certain toxicological experimentation. Development of comprehensive pharmacokinetic descriptions of the influence of saturable clearance on delivery of active chemical to target sites augurs well for improving both intraspecies and interspecies extrapolation of toxicity data. This is a critical area of contemporary toxicology. Dose selection for chronic studies could also be improved by knowledge of the dose-dependence of pharmacokinetic parameters in proposed test species. The field of toxicology reviewed here represents an interface between pharmacokinetic research and studies on basic mechanisms of toxic action. It entails utilization of quantitative concepts to better understand the physiological and biochemical controls which regulate the expression of the toxicity of various chemicals. Much work remains to be accomplished in this exciting area of toxicological research. Some of the predictions of the pharmacokinetic analyses are still tentative and require more definitive experimentation...

88 citations

Journal ArticleDOI
TL;DR: Evidence is presented to demonstrate that materials-directing peptides can be controllably modified to substantially enhance particle functionality without significantly altering nanostructural morphology.
Abstract: Peptide-based methods represent new approaches to selectively produce nanostructures with potentially important functionality. Unfortunately, biocombinatorial methods can only select peptides with target affinity and not for the properties of the final material. In this work, we present evidence to demonstrate that materials-directing peptides can be controllably modified to substantially enhance particle functionality without significantly altering nanostructural morphology. To this end, modification of selected residues to vary the site-specific binding strength and biological recognition can be employed to increase the catalytic efficiency of peptide-capped Pd nanoparticles. These results represent a step toward the de novo design of materials-directing peptides that control nanoparticle structure/function relationships.

87 citations

Journal ArticleDOI
TL;DR: In this paper, the morphology of transmission gratings with varying Bragg spacings formed using polymer-dispersed liquid crystals was examined using high-resolution scanning electron microscopy and image analysis techniques.
Abstract: The morphology of transmission gratings with varying Bragg spacings formed using polymer-dispersed liquid crystals were examined using high-resolution scanning electron microscopy and image analysis techniques. The effect on the morphology of small changes in the overall functionality of the prepolymer syrup was observed. An increase in the amount of monofunctional compound resulted in small, nearly spherical domains (<100 nm in diameter) confined in well-defined lamellae for samples with a 0.49 μm Bragg spacing. A decrease in concentration (an effective increase in monomer functionality) at this Bragg spacing resulted in larger domains (100-200 nm) with much greater distribution of sizes and shapes. The local volume fractions of discrete liquid crystalline (LC) domains was considerably larger in the latter case. An increase in the Bragg spacing to 1.35 μm also resulted in well-defined lamellae of LC domains, although much more coalescence into irregularly shaped individual domains was observed. Surprisingly, the local volume fraction of LC increased in the larger Bragg spacing samples. The morphology results are discussed qualitatively in terms of liquid-gel demixing where the inherent crosslink density and elasticity of the polymeric host must be considered in phase separation processes on the nanoscale.

87 citations

Journal ArticleDOI
TL;DR: The ultrafast response of a pyroelectric sensor with near-infrared responsivity is demonstrated by combining a py roelectric thermal detector with wavelength-selective nanoparticle absorbers.
Abstract: Thermal detectors, such as bolometric, pyroelectric and thermoelectric devices, are uniquely capable of sensing incident radiation for any electromagnetic frequency; however, the response times of practical devices are typically on the millisecond scale1–7. By integrating a plasmonic metasurface with an aluminium nitride pyroelectric thin film, we demonstrate spectrally selective, room-temperature pyroelectric detectors from 660–2,000 nm with an instrument-limited 1.7 ns full width at half maximum and 700 ps rise time. Heat generated from light absorption diffuses through the subwavelength absorber into the pyroelectric film producing responsivities up to 0.18 V W−1 due to the temperature-dependent spontaneous polarization of the pyroelectric films. Moreover, finite-element simulations reveal the possibility of reaching a 25 ps full width at half maximum and 6 ps rise time rivalling that of semiconductor photodiodes8. This design approach has the potential to realize large-area, inexpensive gigahertz pyroelectric detectors for wavelength-specific detection from the ultraviolet to short-wave infrared or beyond for, for example, high-speed hyperspectral imaging. The ultrafast response of a pyroelectric sensor with near-infrared responsivity is demonstrated by combining a pyroelectric thermal detector with wavelength-selective nanoparticle absorbers.

87 citations

Journal ArticleDOI
TL;DR: Artificial hair sensors consisting of a piezoresistive carbon-nanotube-coated glass fiber embedded in a microcapillary that resemble a hair plug that may be integrated in a wide range of host materials are assembled and characterized.
Abstract: Artificial hair sensors consisting of a piezoresistive carbon-nanotube-coated glass fiber embedded in a microcapillary are assembled and characterized. Individual sensors resemble a hair plug that may be integrated in a wide range of host materials. The sensors demonstrate an air-flow detection threshold of less than 1 m/s with a piezoresistive sensitivity of 1.3% per m/s air-flow change.

87 citations


Authors

Showing all 5825 results

NameH-indexPapersCitations
John A. Rogers1771341127390
Liming Dai14178182937
Mark C. Hersam10765946813
Gareth H. McKinley9746734624
Robert E. Cohen9141232494
Michael F. Rubner8730129369
Howard E. Katz8747527991
Melvin E. Andersen8351726856
Eric A. Stach8156542589
Harry L. Anderson8039622221
Christopher K. Ober8063129517
Vladimir V. Tsukruk7948128151
David C. Look7852628666
Richard A. Vaia7632425387
Kirk S. Schanze7351219118
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Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
20234
202211
2021279
2020298
2019290
2018272