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Clonal theory of radiation carcinogenesis

Description: In some cases, usually involving high-LET radiations, the dose response at low doses follows a power function of dose with exponent less than one over a wide dose range. This type of response is of great interest since (a) it implies greater effect per unit dose at progressively smaller doses, and (b) it is not predicted by most models and theories of radiobiology. A theoretical framework is presented for responses having the above characteristics over a dose range extending over a factor of 10… more
Date: January 1, 1982
Creator: Baum, J.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Assessment of the theory and hypotheses of the acidification of watersheds

Description: This report documents and critically assesses the evolution and status of the scientific understanding of the effects of acidic deposition on surface waters. The main conclusion is that the dominant theory of surface-water acidification fails to adequately incorporate many important factors and processes that influence surface water acidity. Some of these factors and processes are not well researched or recognized as being important by most scientists in the aquatic effects research area. 258 r… more
Date: April 1, 1989
Creator: Krug, E.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Jets in e/sup +/e/sup -/ annihilation

Description: We have a simple perturbative picture of the production of hadrons from e/sup +/e/sup -/ annihilations which works quite well in predicting the main features of this interaction. It explains the magnitude of the total cross-section, the basic two-jet structure, and the final state angular distributions. It is also consistent with our present ideas about the structure of hadronic matter and the requirement that at high enough energies, the corrections due to strong interactions are small and hen… more
Date: October 1, 1983
Creator: Hollebeek, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Study of heavy quark production with the Mark II at PEP

Description: The methods adopted by the Mark II collaboration to study heavy quark production at PEP are described. Two complementary techniques are used: D* tagging using the decay chain D*/sup +/. D/sup 0/..pi../sup +/, D/sup 0/ ..-->.. K/sup -/..pi../sup +/, and inclusive lepton tagging using the characteristic p/sub T/ distributions to distinguish contributions from b and c quarks. These techniques are used to derive information about heavy quark fragmentation and about the weak coupling of heavy quarks. more
Date: October 1, 1983
Creator: Abrams, G.; Amidei, D.; Baden, A.; de la Vaissiere, C.; Gidal, G.; Gold, M. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Properties of jets in high-E/sub T/ events produced in pp collisions at. sqrt. s = 63 GeV

Description: The properties of jets in high-E/sub tau/ events produced in pp collisions at ..sqrt..s = 63 GeV have been studied at the CERN Intersecting Storage Rings. The fragmentation of the jets is found to be similar to that of jets produced in e/sup +/e/sup -/ annihilation. The jets are wider than calculated from a constituent scattering model with no hard bremsstrahlung component. The charge correlations of positive and negative particles show differences consistent with expectation from valence-quark… more
Date: July 1, 1983
Creator: Akesson, T.; Albrow, M.G.; Almehed, S.; Batley, R.; Benary, O.; Boggild, H. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Low p/sub T/ inclusive production in hadron-nucleus collisions. [100 GeV/c]

Description: New experimental results on the A dependence of inclusive hadron scattering are described with emphasis on the projectile fragmentation region. The experiment measured h + A ..-->.. h' + x, where h was ..pi../sup +/, K/sup +/, or p; h' was ..pi../sup + -/, K/sup + -/, or p; and A, the nuclear target, was C, Al, Cu, Ag, or Pb. The experimental apparatus consisted of the Fermilab M6E beam line and the Single Arm Spectrometer Facility. An incident beam of 100 GeV/c was used; the produ… more
Date: January 1, 1980
Creator: Barton, D S
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Properties of D* production in e/sup +/e/sup -/ annihilation at 29 GeV

Description: D* production is studied in the decay chain D*/sup +/ ..-->.. D/sup 0/ ..pi../sup +/ with the D/sup 0/ observed in the K/sup -/..pi../sup +/ mode and the corresponding charge conjugate decays. The results were obtained from a preliminary analysis of an 80 pb/sup -1/ data sample of e/sup +/e/sup -/ annihilations at 29 GeV taken with the High Resolution Spectrometer at PEP. The excellent mass resolution of the HRS allows the study of the D* production and decay with very low background. We presen… more
Date: January 1, 1983
Creator: Ahlen, S.; Akerlof, C.; Baranko, G.; Baringer, P.; Beltrami, I.; Bender, D. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fragmentation of relativistic light nuclei: longitudinal and transverse momentum distributions. [0. 93 GeV/c/nucleon, 0. 5 to 11. 5, cross sections, limiting fragmentation, nuclear structure, production mechanism]

Description: The production of charged nuclear fragments was measured in collisions of 0.93 GeV/c/nucleon, 1.75 GeV/c/nucleon, and 2.88 GeV/c/nucleon alpha particles on targets of carbon, copper, lead, and CH/sub 2/, using a double focusing spectrometer. Single particle inclusive cross sections are then presented for the production of protons, deuterons, tritons, /sup 3/He, and /sup 4/He at momenta from 0.5 to 11.5 GeV/c and angles from 0 to 12/sup 0/. The relevance of the concept of limiting fragmentation … more
Date: September 1, 1977
Creator: Anderson, L.M. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Multiplicity of Charged Secondaries in Interactions of Protons in an Emulsion at 400-GeV/c

Description: The preliminary results on multiplicities of charged secondaries in proton-nucleus interactions at 400 Gev/c are presented. Multiplicity of produced particles is consistent in the first approximation with the KNO scaling hypothesis for hadron-nucleus interactions. The relations between different moments of multiplicity distribution in proton-nucleons interactions at high energies are discussed too.
Date: January 1, 1977
Creator: Boos, E.G.; Borisenko, A.I.; Kazanskaya, A.N.; Morozova, P.V.; Pavlova, N.P.; Kholmetskaya, A.V. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A measurement of the top quark's charge

Description: The top quark was discovered in 1995 at the Fermilab National Accelerator Laboratory (Fermilab). One way to confirm if the observed top quark is really the top quark posited in the Standard Model (SM) is to measure its electric charge. In the Standard Model the top quark is the isospin partner of the bottom quark and is expected to have a charge of +2/3. However, an alternative 'exotic' model has been proposed with a fourth generation exotic quark that has the same characteristics, such as mass… more
Date: November 1, 2007
Creator: Unalan, Zeynep Gunay
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Measurement of D^0-\bar{D^0} Mixing From a Time-Dependent Amplitude Analysis of D^0\ -> K^+\pi^-\pi0 Decays

Description: The authors present evidence of D{sup 0}-{bar D}{sup 0} mixing using a time-dependent amplitude analysis of the decay D{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0} in a data sample of 384 fb{sup -1} collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at SLAC. Assuming CP conservation, they measure the mixing parameters x{prime}{sub K{pi}{pi}{sup 0}} = [2.61{sub -0.68}{sup +0.57}(stat.) {+-} 0.39(syst.)]%, y{prime}{sub K{pi}{pi}{sup 0}} = [-0.06{sub -0.64}{sup +0.55}(sta… more
Date: August 4, 2008
Creator: Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department

Discovering and validating biological hypotheses from coherent patterns in functional genomics data

Description: The area of transcriptomics analysis is among the more established in computational biology, having evolved in both technology and experimental design. Transcriptomics has a strong impetus to develop sophisticated computational methods due to the large amounts of available whole-genome datasets for many species and because of powerful applications in regulatory network reconstruction as well as elucidation and modeling of cellular transcriptional responses. While gene expression microarray data… more
Date: August 12, 2008
Creator: Joachimiak, Marcin Pawel
Item Type: Refine your search to only Presentation
Partner: UNT Libraries Government Documents Department
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Observation of Disappearance of Muon Neutrinos in the NuMI Beam

Description: The Main Injector Neutrino Oscillation Search (MINOS) is a two detector long-baseline neutrino experiment designed to study the disappearance of muon neutrinos. MINOS will test the {nu}{sub {mu}} {yields} {nu}{sub {tau}} oscillation hypothesis and measure precisely {Delta}m{sub 23}{sup 2} and sin{sup 2} 2{theta}{sub 23} oscillation parameters. The source of neutrinos for MINOS experiment is Fermilab's Neutrinos at the Main Injector (NuMI) beamline. The energy spectrum and the composition of the… more
Date: May 1, 2008
Creator: Pavlovic, Zarko
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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The Origins of the Rate Enhancement in LiNi0.4Co0.2-yAlyMn0.4O2 (0<y<_0.2) Cathode Materials

Description: Recently, much research has been directed towards finding a replacement cathode material for LiCoO{sub 2} combining high performance with lower cost and toxicity. One promising candidate material is the mixed transition metal oxide LiNi{sub 0.4}Co{sub 0.2}Mn{sub 0.4}O{sub 2}, which delivers 180 mAh/g below 4.4 V versus Li/Li{sup +} (1, 2). However, in this material, there is 4% anti-site cation mixing, which hinders the mobility of lithium within the lattice, adversely affecting its rate perfor… more
Date: May 29, 2008
Creator: Doeff, Marca M; Wilcox, James & Doeff, Marca M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Role of Telomere Dysfunction in Driving Genomic Instability

Description: The mechanistic role of radiation-induced genomic instability in radiation carcinogenesis is an attractive hypothesis that remains to be rigorously tested. There are few in vivo studies on which to base judgments, but work in our laboratory with mouse models of radiogenic mammary neoplasia provided the first indications that certain forms of genetically predisposed radiation-induced genomic instability may contribute to tumor development. The central goal of this research project is to more fir… more
Date: January 17, 2008
Creator: Ullrich, Robert L & Bailey, Susan
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Recent Searches for Exotic Physics at the BaBar/PEP-II B-factory

Description: I present three recent results from searches for exotic physics at the BABAR/PEP-II B-factory. These results span many of the samples produced at the B-factory, including B mesons, {tau} leptons, and {Upsilon}(3S) mesons. We have searched for CPT-violation in B{sup 0} mixing and find no significant deviation from the no-violation hypothesis. We have also searched for lepton-flavor-violating decays of the {tau} using {tau}{sup -} {yields} {omega}{ell}{sup -} and {tau}{sup -} {yields} {ell}{sup -… more
Date: October 22, 2008
Creator: Sekula, Stephen Jacob
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Surface Specularity as an Indicator of Shock-induced Solid-liquid Phase Transitions in Tin

Description: When highly polished metal surfaces melt upon release after shock loading, they exhibit features that suggest significant surface changes accompany the phase transition. The reflection of light from such surfaces changes from specular (pre-shock) to diffuse upon melting. Typical of this phenomenon is the loss of signal light in velocity interferometer system for any reflector (VISAR) measurements, which usually occurs at pressures high enough to melt the free surface. Unlike many other potentia… more
Date: December 1, 2007
Creator: G. D. Stevens, S. S. Lutz, B. R. Marshall, W.D. Turley, et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Discovery of Non-random Spatial Distribution of Impacts in the Stardust Cometary Collector

Description: We report the discovery that impacts in the Stardust cometary collector are not distributed randomly in the collecting media, but appear to be clustered on scales smaller than {approx} 10 cm. We also report the discovery of at least two populations of oblique tracks. We evaluated several hypotheses that could explain the observations. No hypothesis was consistent with all the observations, but the preponderance of evidence points toward at least one impact on the central Whipple shield of the s… more
Date: April 6, 2007
Creator: Westphal, A. J.; Bastien, R. K.; Borg, J.; Bridges, J.; Brownlee, D. E.; Burchell, M. J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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An atmospheric muon neutrino disappearance measurement with the MINOS far detector

Description: It is now widely accepted that the Standard Model assumption of massless neutrinos is wrong, due primarily to the observation of solar and atmospheric neutrino flavor oscillations by a small number of convincing experiments. The MINOS Far Detector, capable of observing both the outgoing lepton and associated showering products of a neutrino interaction, provides an excellent opportunity to independently search for an oscillation signature in atmospheric neutrinos. To this end, a MINOS data set … more
Date: December 1, 2007
Creator: Gogos, Jeremy Peter
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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CeBr3 as a High-Resolution Gamma-Ray Detector

Description: Lanthanum halide (LaBr3:Ce) scintillators have been well-documented as high-resolution gamma-ray detectors that are operated at room temperature. These scintillators have better resolution (<3% at 662 keV) relative to sodium iodide (NaI(Tl)) scintillators (7% at 662 keV), but the naturally occurring radioactive isotope 138La causes self-activity in the crystal that occludes portions of the gamma-ray spectrum. This selfactivity limits the use of LaBr3:Ce in high-sensitivity applications. Cerium,… more
Date: November 13, 2008
Creator: Michael Reed, Paul Guss, Christopher Contreras
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Individual Genetic Susceptibility

Description: Risk estimates derived from epidemiological studies of exposed populations, as well as the maximum permissible doses allowed for occupational exposure and exposure of the public to ionizing radiation are all based on the assumption that the human population is uniform in its radiosensitivity, except for a small number of individuals, such as ATM homozygotes who are easily identified by their clinical symptoms. The hypothesis upon which this proposal is based is that the human population is not … more
Date: December 8, 2008
Creator: Hall, Eric J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Translating the cancer genome: Going beyond p values

Description: Cancer cells are endowed with diverse biological capabilities driven by myriad inherited and somatic genetic and epigenetic aberrations that commandeer key cancer-relevant pathways. Efforts to elucidate these aberrations began with Boveri's hypothesis of aberrant mitoses causing cancer and continue today with a suite of powerful high-resolution technologies that enable detailed catalogues of genomic aberrations and epigenomic modifications. Tomorrow will likely bring the complete atlas of rever… more
Date: April 3, 2008
Creator: Chin, Lynda; Chin, Lynda & Gray, Joe W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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An experimental study of the impact of location on the effectiveness of recruitment clusters for Red-cockaded Woodpeckers at the Savannah River Site.

Description: An experimental study of the impact of location on the effectiveness of recruitment clusters for Red-Cockaded Woodpeckers at the Savannah River Site.
Date: May 31, 2008
Creator: Walters, Jeffrey, R.; Johnston, Peter, A.; Crowder, Larry, B. & Priddy, Jeffrey, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Changes in vigorous physical activity and incident diabetes inmale runners

Description: We examined the dose-response relationship between changes in reported vigorous exercise (running distance, {Delta}km/wk) and self-reported physician diagnosed diabetes in 25,988 men followed prospectively for (mean {+-} SD) 7.8 {+-} 1.8 years. Logistic regression analyses showed that the log odds for diabetes declined significantly in relation to men's {Delta}km/wk (coefficient {+-} SE: -0.012 {+-} 0.004, P &lt; 0.01), which remained significant when adjusted for BMI (-0.018 {+-} 0.003, P &lt;… more
Date: April 30, 2007
Creator: Williams, Paul T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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