702 research outputs found
Urban West Revisited: Governing Cities in Uncertain Times
Urban West Revisited offers a colorful primer on challenges faced by elected officials in midsized western cities. Featuring ten bellwether citiesâBoise, Eugene, Modesto, Pueblo, Reno, Salem, Salt Lake, Spokane, Tacoma, and Tempeâthe exploration finds common problems and hard-fought solutions in difficult times.https://scholarworks.boisestate.edu/fac_books/1365/thumbnail.jp
Realâtime Bâmode ultrasound quality control test procedures. Report of AAPM Ultrasound Task Group No. 1
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134873/1/mp8404.pd
Exact solutions to chaotic and stochastic systems
We investigate functions that are exact solutions to chaotic dynamical
systems. A generalization of these functions can produce truly random numbers.
For the first time, we present solutions to random maps. This allows us to
check, analytically, some recent results about the complexity of random
dynamical systems. We confirm the result that a negative Lyapunov exponent does
not imply predictability in random systems. We test the effectiveness of
forecasting methods in distinguishing between chaotic and random time-series.
Using the explicit random functions, we can give explicit analytical formulas
for the output signal in some systems with stochastic resonance. We study the
influence of chaos on the stochastic resonance. We show, theoretically, the
existence of a new type of solitonic stochastic resonance, where the shape of
the kink is crucial. Using our models we can predict specific patterns in the
output signal of stochastic resonance systems.Comment: 31 pages, 18 figures (.eps). To appear in Chaos, March 200
Demonstration of methods for analytical measurement of natural circulation flow in EBR-II
Statement of responsibility on title page reads: R. J. Witt and J. E. Meyer, Includes MIT technical contributions from J. I. Choi, D. D. Lanning, J. E. Meyer, A. L. Schor, R. J. Witt and R. D. Wittmeier.""February, 1986."Includes bibliographical references (leaf 44)Final project reportSupported by U.S. Dept. of Energy, Breeder Technology Program, Division of Educational Programs, Argonne National Laborator
Building on the past, shaping the future: The environmental mutagenesis and genomics society
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97167/1/em21765.pd
Opportunities to integrate new approaches in genetic toxicology: An ILSI-HESI workshop report
Genetic toxicity tests currently used to identify and characterize potential human mutagens and carcinogens rely on measurements of primary DNA damage, gene mutation, and chromosome damage in vitro and in rodents. The International Life Sciences Institute Health and Environmental Sciences Institute (ILSI-HESI) Committee on the Relevance and Follow-up of Positive Results in In Vitro Genetic Toxicity Testing held an April 2012 Workshop in Washington, DC, to consider the impact of new understanding of biology and new technologies on the identification and characterization of genotoxic substances, and to identify new approaches to inform more accurate human risk assessment for genetic and carcinogenic effects. Workshop organizers and speakers were from industry, academe, and government. The Workshop focused on biological effects and technologies that would potentially yield the most useful information for evaluating human risk of genetic damage. Also addressed was the impact that improved understanding of biology and availability of new techniques might have on genetic toxicology practices. Workshop topics included (1) alternative experimental models to improve genetic toxicity testing, (2) Biomarkers of epigenetic changes and their applicability to genetic toxicology, and (3) new technologies and approaches. The ability of these new tests and technologies to be developed into tests to identify and characterize genotoxic agents; to serve as a bridge between in vitro and in vivo rodent, or preferably human, data; or to be used to provide dose response information for quantitative risk assessment was also addressed. A summary of the workshop and links to the scientific presentations are provided.International Life Sciences Institute/Health and Environmental Sciences Institute Committe
Multi-Messenger Gravitational Wave Searches with Pulsar Timing Arrays: Application to 3C66B Using the NANOGrav 11-year Data Set
When galaxies merge, the supermassive black holes in their centers may form
binaries and, during the process of merger, emit low-frequency gravitational
radiation in the process. In this paper we consider the galaxy 3C66B, which was
used as the target of the first multi-messenger search for gravitational waves.
Due to the observed periodicities present in the photometric and astrometric
data of the source of the source, it has been theorized to contain a
supermassive black hole binary. Its apparent 1.05-year orbital period would
place the gravitational wave emission directly in the pulsar timing band. Since
the first pulsar timing array study of 3C66B, revised models of the source have
been published, and timing array sensitivities and techniques have improved
dramatically. With these advances, we further constrain the chirp mass of the
potential supermassive black hole binary in 3C66B to less than using data from the NANOGrav 11-year data set. This
upper limit provides a factor of 1.6 improvement over previous limits, and a
factor of 4.3 over the first search done. Nevertheless, the most recent orbital
model for the source is still consistent with our limit from pulsar timing
array data. In addition, we are able to quantify the improvement made by the
inclusion of source properties gleaned from electromagnetic data to `blind'
pulsar timing array searches. With these methods, it is apparent that it is not
necessary to obtain exact a priori knowledge of the period of a binary to gain
meaningful astrophysical inferences.Comment: 14 pages, 6 figures. Accepted by Ap
Dust and Super Star Clusters in NGC 5253
We present new observations of the famous starburst galaxy NGC 5253 which
owes its celebrity to possibly being the youngest and closest starburst galaxy
known. Our observations in the infrared and millimeter contribute to shed light
on the properties of this interesting object. We have used our new data along
with data from the literature to study the properties of the young stellar
clusters present in NGC 5253. We find that the brightest optical clusters are
all characterized by a near-infrared excess that is explained by the combined
effect of extinction and emission by dust. For the brightest infrared cluster
we model the spectral energy distribution from the optical to the radio. We
find that this cluster dominates the galaxy emission longward of 3 \mic, that
it has a bolometric luminosity of and a mass of , giving . The cluster is obscured by 7 mag of
optical extinction produced by about 1.5 10 of dust. The dust
properties are peculiar with respect to the dust properties in the solar
neighbourhood with a composition characterized by a lack of silicates and a
flatter size distribution than the standard one, i.e. a bias toward larger
grains. We find that NGC 5253 is a striking example of a galaxy where the
infrared-submillimeter and ultraviolet-optical emissions originate in totally
decoupled regions of vastly different physical sizes.Comment: 13 pages, 3 figure
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