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Recent hybrid origin of three rare chinese turtles

Description: Three rare geoemydid turtles described from Chinese tradespecimens in the early 1990s, Ocadia glyphistoma, O. philippeni, andSacalia pseudocellata, are suspected to be hybrids because they are knownonly from their original descriptions and because they have morphologiesintermediate between other, better-known species. We cloned the allelesof a bi-parentally inherited nuclear intron from samples of these threespecies. The two aligned parental alleles of O. glyphistoma, O.philippeni, and S. pseudocellata have 5-11.5 times more heterozygouspositions than do 13 other geoemydid species. Phylogenetic analysis showsthat the two alleles from each turtle are strongly paraphyletic, butcorrectly match sequences of other species that were hypothesized frommorphology to be their parental species. We conclude that these rareturtles represent recent hybrids rather than valid species. Specifically,"O. glyphistoma" is a hybrid of Mauremys sinensis and M. cf. annamensis,"O. philippeni" is a hybrid of M. sinensis and Cuora trifasciata, and "S.pseudocellata" is a hybrid of C. trifasciata and S. quadriocellata.Conservation resources are better directed toward finding and protectingpopulations of other rare Southeast Asian turtles that do representdistinct evolutionary lineages.
Date: February 7, 2006
Creator: Stuart, Bryan L. & Parham, James F.
Partner: UNT Libraries Government Documents Department

Mesoscopic structure conditions the emergence of cooperation on social networks

Description: We study the evolutionary Prisoner's Dilemma on two social networks substrates obtained from actual relational data. We find very different cooperation levels on each of them that cannot be easily understood in terms of global statistical properties of both networks. We claim that the result can be understood at the mesoscopic scale, by studying the community structure of the networks. We explain the dependence of the cooperation level on the temptation parameter in terms of the internal structure of the communities and their interconnections. We then test our results on community-structured, specifically designed artificial networks, finding a good agreement with the observations in both real substrates. Our results support the conclusion that studies of evolutionary games on model networks and their interpretation in terms of global properties may not be sufficient to study specific, real social systems. Further, the study allows us to define new quantitative parameters that summarize the mesoscopic structure of any network. In addition, the community perspective may be helpful to interpret the origin and behavior of existing networks as well as to design structures that show resilient cooperative behavior.
Date: December 1, 2008
Creator: Lozano, S.; Arenas, A. & Sanchez, A.
Partner: UNT Libraries Government Documents Department

On social sensitivity to either zealot or independent minorities

Description: This article uses the self-organized temporal criticality (SOTC) model to identify the timing of crucial events as a new mechanism with which to generate criticality, thereby establishing a way for the internal dynamics of the decision making process to suppresss the sensitivity of social opinion to either zealot or independent minorities.
Date: March 27, 2018
Creator: Mahmoodi, Korosh; Grigolini, Paolo & West, Bruce J.
Partner: UNT College of Arts and Sciences

Wet Mountains, Colorado, Thorium Investigations 1952-1954

Description: A report about a 22-square mile tract of pre-Cambrain rocks and veins containing thorium mapped at the scale of 1:6,000 located on the west flank of the Wet Mountains, Custer and Fremont Counties, northeast of Westcliffe, Colorado.
Date: August 1954
Creator: Christman, R. A.; Brock, M. R.; Pearson, R. C. & Singewald, Q. D.
Partner: UNT Libraries Government Documents Department

Models and Measurements: Complementary Tools for Predicting Atmospheric Dispersion and Assessing the Consequences of Nuclear and Radiological Emergencies

Description: Since its inception over 26 years ago, NARAC (the National Atmospheric Release and Advisory Center) has used measurement data to update model predictions of radioactive releases from known origins. NARAC continues to routinely participate in emergency response drills with organizations that collect air concentration, ground deposition, and radiation exposure measurements. From a complementary perspective, NARAC is now developing an advanced capability to combine models and data from monitoring systems to characterize and forensically reconstruct atmospheric release events of unknown origin.
Date: November 7, 2005
Creator: Bradley, M M; Kosovic, B & Nasstrom, J S
Partner: UNT Libraries Government Documents Department

qSF wavefront triplication in a transversely isotropicmaterial

Description: Triplication of a wavefront, also classically known as birefringence, can and does occur in transversely isotropic (TI) media. With the growing interest in shear waves, and in particular, converted shear waves, it becomes necessary to study this phenomenon, and the bright spots that accompany it. In a plane that includes the medium's rotational symmetry axis, there may exist a range of angles within which the qSV wave, whose polarization lies in that plane, may propagate at three distinct velocities. The region of the qSV wave curve where this can occur always corresponds to the region of the qSV slowness curve where the closed qSV curve about the origin is concave. When the range of angles is small and the three arrivals are close together, the usual situation, the qSV wave within that small range will be significantly brighter than in other directions. When the range of angles is large, the two cusps of the wave surface, on the borders of the region of triplication will both be bright spots.
Date: June 1, 2004
Creator: Schoenberg, Michael & Daley, Thomas M.
Partner: UNT Libraries Government Documents Department

CP Violation and B Physics

Description: This is a quick review of CP non-conservation in B physics. Several methods are described for testing the Kobayashi-Maskawa single phase origin of CP violation in B decays, pointing out some limitations due to hadronic uncertainties. A few characteristic signatures of new physics in B decay asymmetries are listed.
Date: August 17, 1999
Creator: Gronau, Michael
Partner: UNT Libraries Government Documents Department

The DOE Model for Improving Seismic Event Locations Using Travel Time Corrections: Description and Demonstration

Description: The U.S. National Laboratories, under the auspices of the Department of Energy, have been tasked with improv- ing the capability of the United States National Data Center (USNDC) to monitor compliance with the Comprehen- sive Test Ban Trea~ (CTBT). One of the most important services which the USNDC must provide is to locate suspicious events, preferably as accurately as possible to help identify their origin and to insure the success of on-site inspections if they are deemed necessary. The seismic location algorithm used by the USNDC has the capability to generate accurate locations by applying geographically dependent travel time corrections, but to date, none of the means, proposed for generating and representing these corrections has proven to be entirely satisfactory. In this presentation, we detail the complete DOE model for how regional calibration travel time information gathered by the National Labs will be used to improve event locations and provide more realistic location error esti- mates. We begin with residual data and error estimates from ground truth events. Our model consists of three parts: data processing, data storage, and data retrieval. The former two are effectively one-time processes, executed in advance before the system is made operational. The last step is required every time an accurate event location is needed. Data processing involves applying non-stationary Bayesian kriging to the residwd data to densifi them, and iterating to find the optimal tessellation representation for the fast interpolation in the data retrieval task. Both the kriging and the iterative re-tessellation are slow, computationally-expensive processes but this is acceptable because they are performed off-line, before any events are to be located. In the data storage task, the densified data set is stored in a database and spatially indexed. Spatial indexing improves the access efficiency of the geographically-ori- ented data requests associated with event ...
Date: October 20, 1998
Creator: Hipp, J.R.; Moore, S.G.; Shepherd, E. & Young, C.J.
Partner: UNT Libraries Government Documents Department

A possible hadronic excess in psi(2S) decay and the rho pi puzzle

Description: We study the so-called {rho}{pi} puzzle of the {psi}(2S) decay by incorporating two inputs; the relative phase between the one-photon and the gluonic decay amplitude, and a possible hadronic excess in the inclusive nonelectromagnetic decay rate of {psi}(2S). We look into the possibility that the hadronic excess in {psi}(2S) originates from a decay process of long-distance origin which is absent from the J/{upsilon} decay. We propose that the amplitude of this additional process happens to nearly cancel the short-distance gluonic amplitude in the exclusive decay {psi}(2S) {yields} 1{sup -}0{sup -} and turn the sum dominantly real in contrast to the J/{psi} decay. We present general consequences of this mechanism and survey two models which might possibly explain the source of this additional amplitude.
Date: November 9, 2000
Creator: Suzuki, Mahiko
Partner: UNT Libraries Government Documents Department

Molecular mechanisms of extensive mitochondrial gene rearrangementin plethodontid salamanders

Description: Extensive gene rearrangement is reported in the mitochondrial genomes of lungless salamanders (Plethodontidae). In each genome with a novel gene order, there is evidence that the rearrangement was mediated by duplication of part of the mitochondrial genome, including the presence of both pseudogenes and additional, presumably functional, copies of duplicated genes. All rearrangement-mediating duplications include either the origin of light strand replication and the nearby tRNA genes or the regions flanking the origin of heavy strand replication. The latter regions comprise nad6, trnE, cob, trnT, an intergenic spacer between trnT and trnP and, in some genomes, trnP, the control region, trnF, rrnS, trnV, rrnL, trnL1, and nad1. In some cases, two copies of duplicated genes, presumptive regulatory regions, and/or sequences with no assignable function have been retained in the genome following the initial duplication; in other genomes, only one of the duplicated copies has been retained. Both tandem and non-tandem duplications are present in these genomes, suggesting different duplication mechanisms. In some of these mtDNAs, up to 25 percent of the total length is composed of tandem duplications of non-coding sequence that includes putative regulatory regions and/or pseudogenes of tRNAs and protein-coding genes along with otherwise unassignable sequences. These data indicate that imprecise initiation and termination of replication, slipped-strand mispairing, and intra-molecular recombination may all have played a role in generating repeats during the evolutionary history of plethodontid mitochondrial genomes.
Date: June 1, 2005
Creator: Mueller, Rachel Lockridge & Boore, Jeffrey L.
Partner: UNT Libraries Government Documents Department

Rostral horn evolution among agamid lizards of the genus ceratophora endemic to Sri Lanka

Description: The first phylogenetic hypothesis for the Sri Lankan agamid lizard genus Ceratophora is presented based on 1670 aligned base positions (472 parsimony informative) of mitochondrial DNA sequences, representing coding regions for eight tRNAs, ND2, and portions of ND1 and COI. Phylogenetic analysis reveals multiple origins and possibly losses of rostral horns in the evolutionary history of Ceratophora. Our data suggest a middle Miocene origin of Ceratophora with the most recent branching of recognized species occurring at the Pliocene/Pleistocene boundary. Haplotype divergence suggests that an outgroup species, Lyriocephalus scutatus, dates at least to the Pliocene. These phylogenetic results provide a framework for comparative studies of the behavioral ecological importance of horn evolution in this group.
Date: July 10, 2001
Creator: Schulte II, James A.; Macey, J. Robert; Pethiyagoda, Rohan & Larson, Allan
Partner: UNT Libraries Government Documents Department

V-shaped inversion domains in InN grown on c-plane sapphire

Description: Inversion domains with a V-shape were found to nucleate inside a Mg-doped InN heteroepitaxial layer. They resemble Al-polarity domains, observed recently, in N-polarity AlN films. However, the angle between the side-walls of the V-shaped domain and the c-axis differs in these two cases. In InN, this angle is almost two times bigger than that reported for AlN. The origin of V-shaped inversion domains in InN film is not yet clear.
Date: April 27, 2004
Creator: Jasinski, J.; Liliental-Weber, Z.; Lu, H. & Schaff, W.J.
Partner: UNT Libraries Government Documents Department

Long baseline neutrino oscillations: Parameter degeneracies and JHF/NuMI complementarity

Description: A summary of the parameter degeneracy issue for long baseline neutrino oscillations is presented and how a sequence of measurements can be used to resolve all degeneracies. Next, a comparison of the JHF and NuMI Off-Axis proposals is made with emphasis on how both experiments running neutrinos can distinguish between the normal and inverted hierarchies provided the E/L of NuMI is less than or equal to the E/L of JHF. Due to the space limitations of this proceedings only an executive style summary can be presented here, but the references and transparencies of the talk contain the detailed arguments.
Date: October 13, 2003
Creator: Parke, Stephen; Minakata, Hisakazu & Nunokawa, Hiroshi
Partner: UNT Libraries Government Documents Department

Possible origin of RHIC R{sub out}/R{sub sid} HBT results

Description: The effects of opacity of the nuclei together with a blackbody type of emission along the system history are considered as a means to explain the ratio R{sub out}=R{sub sid} observed by STAR and PHENIX collaborations at RHIC. Within our model, no flow is required to explain the data trend of this ratio for large surface emissivities.
Date: September 30, 2002
Creator: Padula, Sandra S.
Partner: UNT Libraries Government Documents Department

Comparison of the oxidation state of Fe in comet 81P/Wild 2 and chondritic-porous interplanetary dust particles

Description: The fragile structure of chondritic-porous interplanetary dust particles (CP-IDPs) and their minimal parent-body alteration have led researchers to believe these particles originate in comets rather than asteroids where aqueous and thermal alterations have occurred. The solar elemental abundances and atmospheric entry speed of CP-IDPs also suggest a cometary origin. With the return of the Stardust samples from Jupiter-family comet 81P/Wild 2, this hypothesis can be tested. We have measured the Fe oxidation state of 15 CP-IDPs and 194 Stardust fragments using a synchrotron-based x-ray microprobe. We analyzed {approx}300 ng of Wild 2 material - three orders of magnitude more material than other analyses comparing Wild 2 and CP-IDPs. The Fe oxidation state of these two samples of material are > 2{sigma} different: the CP-IDPs are more oxidized than the Wild 2 grains. We conclude that comet Wild 2 contains material that formed at a lower oxygen fugacity than the parent-body, or parent bodies, of CP-IDPs. If all Jupiter-family comets are similar, they do not appear to be consistent with the origin of CP-IDPs. However, comets that formed from a different mix of nebular material and are more oxidized than Wild 2 could be the source of CP-IDPs.
Date: July 16, 2010
Creator: Ogliore, Ryan C.; Butterworth, Anna L.; Fakra, Sirine C.; Gainsforth, Zack; Marcus, Matthew A. & Westphal, Andrew J.
Partner: UNT Libraries Government Documents Department

Time reversal and the spatio-temporal matched filter

Description: It is known that focusing of an acoustic field by a time-reversal mirror (TRM) is equivalent to a spatio-temporal matched filter under conditions where the Green's function of the field satisfies reciprocity and is time invariant, i.e. the Green's function is independent of the choice of time origin. In this letter, it is shown that both reciprocity and time invariance can be replaced by a more general constraint on the Green's function that allows a TRM to implement the spatio-temporal matched filter even when conditions are time varying.
Date: March 8, 2004
Creator: Lehman, S K; Poggio, A J; Kallman, J S; Meyer, A W & Candy, J V
Partner: UNT Libraries Government Documents Department

EXTRATERRESTRIAL LIFE: SOME ORGANIC CONSTITUENTS OF METEORITES ANDTHEIR SIGNIFICANCE FOR POSSIBLE EXTRATERRESTRIAL BIOLOGICALEVOLUTION

Description: In order to decide the value and type of information to be obtained from outer space with regard to its pertinence for the evolution of life, a brief review is presented of the current status of our thinking on the origin of life on earth. This points up the particular kinds of chemicals whose presence, or absence, on other astral bodies might be significant. Heretofore, the only data available are the result of telescopic spectroscopy. We report here information indicating the presence in meteorites of complex organic materials, some of them apparently uniquely pertinent to life processes.
Date: December 7, 1959
Creator: Calvin, Melvin & Vaughn, Susan K.
Partner: UNT Libraries Government Documents Department