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2005

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Articles 4951 - 4980 of 5573

Full-Text Articles in Physical Sciences and Mathematics

An Improved Software Process Management Tool: Remote (Recursively Estimating Multi-Threaded Observation Tool Enterprise), Shujiang Xia Jan 2005

An Improved Software Process Management Tool: Remote (Recursively Estimating Multi-Threaded Observation Tool Enterprise), Shujiang Xia

Theses Digitization Project

The principal purpose of the project is to enable ReMoTe support for multi-databases. ReMoTe stands for the Recursively Estimating Multi-Threaded Observation Technology Enterprise, which is a web-based computer aided software engineering tool for monitoring software development process. Development of ReMoTe is based on the RMT (Recursive Multi-Threaded) software life cycle developed by Scott Simon, a CSUSB alum, in his master's thesis in 1997. ReMoTe enables the monitoring of projects that use different databases in various locations. Central management can view the progress information of each project using a web browser no matter where the database or project team is located. …


Food Wholesale Ordering System, Dennis Meng Yann Hsieh Jan 2005

Food Wholesale Ordering System, Dennis Meng Yann Hsieh

Theses Digitization Project

FWOS (Food Wholesaler Ordering System) demonstrates the application of web services to provide an ecommerce solution for general food wholesaler and their customers. The main goal of this project is to provide graphical user interfaces for the four user types including visitor, member, sales person and sales manager. The system provides a contact base ordering system, an account management sub-system, and a powerful accounting subsystem.


Online Solicitation Management System For The Office Of Technology Transfer And Commercialization, Chia-Chi Wang Jan 2005

Online Solicitation Management System For The Office Of Technology Transfer And Commercialization, Chia-Chi Wang

Theses Digitization Project

The Online Solicitation Management System (OSMS) is a web-based system designed for California State University, San Bernardino's Office of Technology Transfer and Commercialization (OTTC) to run grant proposal solicitations more efficiently. The system accepts grant proposals, finds the best matched evaluators, calculates evaluation scores, and generated reports. Users in the system are divided into five (5) different roles: system administrator, program officer, staff, evaluator and applicant.


A Study Of The Relationships Between End-User Information Systems Problems And Helpdesk Critical Success Factors In Higher Education, Richard Dale Parrott Jan 2005

A Study Of The Relationships Between End-User Information Systems Problems And Helpdesk Critical Success Factors In Higher Education, Richard Dale Parrott

CCE Theses and Dissertations

In the last fifteen years, information technology (IT) customer support has increased in importance within higher education. The pervasiveness of computers and technology on the campus has allowed students, staff, and faculty to perform a multitude of tasks by controlling their own environments and setting their own priorities. Qualified professional system and user support services have lagged demand. The problem investigated in this study was end-users' satisfaction levels of the higher education helpdesk and how end-users' satisfaction levels affected a helpdesk manager's critical success factors performance and goals. In this study, the first goal was to identify the critical success …


Predicting Software Size And Development Effort: Models Based On Stepwise Refinement, David P. Voorhees Jan 2005

Predicting Software Size And Development Effort: Models Based On Stepwise Refinement, David P. Voorhees

CCE Theses and Dissertations

This study designed a Software Size Model and an Effort Prediction Model, then performed an empirical analysis of these two models. Each model design began with identifying its objectives, which led to describing the concept to be measured and the meta-model. The numerical assignment rules were then developed, providing a basis for size measurement and effort prediction across software engineering projects. The Software Size Model was designed to test the hypothesis that a software size measure represents the amount of knowledge acquired and stored in software artifacts, and the amount of time it took to acquire and store this knowledge. …


Making Sense Of Nanocrystal Lattice Fringes, P. Fraundorf, Wentao Qin, Peter Moeck, Eric Mandell Jan 2005

Making Sense Of Nanocrystal Lattice Fringes, P. Fraundorf, Wentao Qin, Peter Moeck, Eric Mandell

Physics Faculty Publications and Presentations

The orientation dependence of thin-crystal lattice fringes can be gracefully quantified using fringe-visibility maps, a direct-space analog of Kikuchi maps [Nishikawa and Kikuchi, Nature (London) 121, 1019 (1928)]. As in navigation of reciprocal space with the aid of Kikuchi lines, fringe-visibility maps facilitate acquisition of crystallographic information from lattice images. In particular, these maps can help researchers to determine the three-dimensional lattice of individual nanocrystals, to 'fringe-fingerprint' collections of randomly oriented particles, and to measure local specimen thickness with only a modest tilt. Since the number of fringes in an image increases with maximum spatial-frequency squared, these strategies (with help …


Cns Connections, Winter 2005-06, University Of Northern Iowa. College Of Natural Sciences. Jan 2005

Cns Connections, Winter 2005-06, University Of Northern Iowa. College Of Natural Sciences.

CNS Connections

Inside this issue:

-- Message from the Dean
-- At Last: An updated home for Physics
-- PSM degrees a coming attraction at UNI
-- CEEE celebrates 10 productive years
-- CNS inaugurates special Preview Day
-- Faculty and Student Research Highlights
-- Purple Pride
-- UNI offers many opportunities in the classroom and beyond
-- Update from the Centers
-- Two programs increase diversity in Math Department
-- College News
-- ChemWall provides passport to Chemistry at UNI
-- Industrial Tech students build renewable energy system at area park
-- Alumni News
-- CNS Advisory Board


Water Resources Year In Review - Winter 2005, Vol. 18, No. 2, Annis Water Resource Institute Jan 2005

Water Resources Year In Review - Winter 2005, Vol. 18, No. 2, Annis Water Resource Institute

AWRI Reviews

No abstract provided.


Entropic Analysis Of Color Homogeneity, Kirill Alemaskin, Ica Manas Zloczower, Miron Kaufman Jan 2005

Entropic Analysis Of Color Homogeneity, Kirill Alemaskin, Ica Manas Zloczower, Miron Kaufman

Physics Faculty Publications

We propose an entropic measure to assess color homogeneity as well as deviations from a standard/ideal color. We illustrate the concept by analyzing samples obtained in a single screw extruder by mixing blue and yellow polymer pellets. Alternatively the proposed technique can be employed to assess the efficiency and degree of distributive mixing attained in polymer processing equipment.


320-Channel Dual Phase Lock-In Optical Spectrometer, Petru S. Fodor, S. Rothenberger, J. Levy Jan 2005

320-Channel Dual Phase Lock-In Optical Spectrometer, Petru S. Fodor, S. Rothenberger, J. Levy

Physics Faculty Publications

The development of a multiple-channel lock-in optical spectrometer (LIOS) is presented, which enables parallel phase-sensitive detection at the output of an optical spectrometer. The light intensity from a spectrally broad source is modulated at the reference frequency, and focused into a high-resolution imaging spectrometer. The height at which the light enters the spectrometer is controlled by an acousto-optic deflector, and the height information is preserved at the output focal plane. A two-dimensional InGaAs focal plane array collects light that has been dispersed in wavelength along the horizontal direction, and in time along the vertical direction. The data is demodulated using …


Epr And X-Ray Crystallographic Characterization Of The Product-Bound Form Of The MnIi-Loaded Methionyl Aminopeptidase From Pyrococcus Furiosus, Alicja J. Copik, Boguslaw P. Nocek, Sabina I. Swierczek, Shane Ruebush, Se Bok Jang, Lu Meng, Ventris M. D'Souza, John W. Peters, Brian Bennett, Richard C. Holz Jan 2005

Epr And X-Ray Crystallographic Characterization Of The Product-Bound Form Of The MnIi-Loaded Methionyl Aminopeptidase From Pyrococcus Furiosus, Alicja J. Copik, Boguslaw P. Nocek, Sabina I. Swierczek, Shane Ruebush, Se Bok Jang, Lu Meng, Ventris M. D'Souza, John W. Peters, Brian Bennett, Richard C. Holz

Physics Faculty Research and Publications

Methionine aminopeptidases (MetAPs) are ubiquitous metallohydrolases that remove the N-terminal methionine from nascent polypeptide chains. Although various crystal structures of MetAP in the presence of inhibitors have been solved, the structural aspects of the product-bound step has received little attention. Both perpendicular- and parallel-mode electron paramagnetic resonance (EPR) spectra were recorded for the MnII-loaded forms of the type-I (Escherichia coli) and type-II (Pyrococcus furiosus) MetAPs in the presence of the reaction product l-methionine (l-Met). In general, similar EPR features were observed for both [MnMn(EcMetAP-I)]−l-Met and [MnMn(PfMetAP-II)]−l-Met. The observed perpendicular-mode EPR …


Mercury Contamination Of Channel And Floodplain Sediments In Wilson Creek Watershed, Southwest Missouri, Willard E. Rodgers Ii Jan 2005

Mercury Contamination Of Channel And Floodplain Sediments In Wilson Creek Watershed, Southwest Missouri, Willard E. Rodgers Ii

MSU Graduate Theses

Mercury (Hg) is a pollutant affecting aquatic environments and human health world wide. Sediments in urban streams can store Hg from historical industrial waste releases in channel and floodplain deposits. Subsequent erosion of these deposits can remobilize sediment-bound Hg impacting downstream receiving waters. This study describes the distribution of Hg in floodplain and channel sediments of Wilson Creek and its tributaries using geochemical sediment analysis and cesium-137 dating. The upper Wilson Creek watershed drains the southern two-thirds of Springfield, Missouri. Results indicate that Hg concentrations in overbank and active channel sediments along the entire stream length are elevated above the …


Measurement Of Charm Fragmentation Ratios And Fractions In Photoproduction At Hera, S. Chekanov, M. Derrick, S. Magill, S. Miglioranzi, B. Musgrave, J. Repond, R. Yoshida, Margarita C. K. Mattingly, N. Pavel, A. G. Yagües Molina, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, A. Margotti, A. Montanari, R. Nania, F. Palmonari, A. Pesci, A. Polini Jan 2005

Measurement Of Charm Fragmentation Ratios And Fractions In Photoproduction At Hera, S. Chekanov, M. Derrick, S. Magill, S. Miglioranzi, B. Musgrave, J. Repond, R. Yoshida, Margarita C. K. Mattingly, N. Pavel, A. G. Yagües Molina, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, A. Margotti, A. Montanari, R. Nania, F. Palmonari, A. Pesci, A. Polini

Faculty Publications

© 2005, Springer New York LLC. All rights reserved. The production of D∗+, D0, D+, D+s and Λ+c charm hadrons and their antiparticles in ep scattering at HERA was measured with the ZEUS detector using an integrated luminosity of 79 pb−1. The measurement has been performed in the photoproduction regime with the exchanged-photon virtuality Q2 < 1GeV2 and for photon-proton centre-of-mass energies in the range 130 3.8GeV and pseudorapidity |η(D,Λc)| < 1.6. The production cross sections were used to determine the ratio of neutral and charged D-meson production rates, Ru/d, the strangeness-suppression factor, γs, and the fraction of charged D mesons produced in a vector state, Pdv. The measured Ru/d and γs values agree with those obtained in deep inelastic scattering and in e+e- annihilations. The measured Pdv value is smaller than, but consistent with, the previous measurements. The fractions of c quarks hadronising as a particular charm hadron, f(c → D, Λc), were derived in the given kinematic range. The measured open-charm fragmentation fractions are consistent with previous results, although the measured f(c → D*+) is smaller and f(c → Λ+c) is larger than those obtained in e+e- annihilations. These results generally support the hypothesis that fragmentation proceeds independently of the hard sub-process.


Farrell's Spider, Jeremiah Farrell, Ivan Moscovich Jan 2005

Farrell's Spider, Jeremiah Farrell, Ivan Moscovich

Scholarship and Professional Work - LAS

Puzzle game featured in Ivan Moscovich's magnetic puzzle pack:

Place the 18 discs on the web so that the sum of the numbers on each of the three hexagons and on each of the three ribs equals 57.


Intermediate Phase Of The One Dimensional Half-Filled Hubbard-Holstein Model, R. T. Clay, Rahul Hardikar Jan 2005

Intermediate Phase Of The One Dimensional Half-Filled Hubbard-Holstein Model, R. T. Clay, Rahul Hardikar

Scholarship and Professional Work - LAS

We present a numerical study of the Hubbard-Holstein model in one dimension at half filling, including finite-frequency quantum phonons. At half filling, the effects of the electron-phonon and electron-electron interactions compete with the Holstein phonon coupling acting as an effective negative Hubbard on-site interaction U that promotes on-site electron pairs and a Peierls charge-density wave state. Most previous work on this model has assumed that only Peierls or Mott phases are possible at half filling. However, there has been speculation that a third metallic phase exists between the Peierls and Mott phases. We confirm the intermediate phase, and show that …


Projectile-Residual-Target-Ion Scattering After Single Ionization Of Helium By Slow Proton Impact, N. V. Maydanyuk, Ahmad Hasan, M. Foster, B. Tooke, Don H. Madison, Michael Schulz, Emilio Nanni Jan 2005

Projectile-Residual-Target-Ion Scattering After Single Ionization Of Helium By Slow Proton Impact, N. V. Maydanyuk, Ahmad Hasan, M. Foster, B. Tooke, Don H. Madison, Michael Schulz, Emilio Nanni

Physics Faculty Research & Creative Works

We have measured fully differential single ionization cross sections for 75 keV p+He collisions. At this relatively small projectile velocity, signatures of the projectile-residual-target-ion interaction, which are not observable for fast projectiles and for electron impact, are revealed rather sensitively. In fact, this interaction appears to be more important than the postcollision interaction, which so far was assumed to be the most important factor in higher-order effects for slow ion impact. These features are not well reproduced by our three-distorted-wave calculations.


Study Of An Acrylamide-Based Photopolymer For Use As A Holographic Data Storage Medium, Hosam Sherif, Izabela Naydenova, Suzanne Martin, Colm Mcginn, G Berger, C Denz, Vincent Toal Jan 2005

Study Of An Acrylamide-Based Photopolymer For Use As A Holographic Data Storage Medium, Hosam Sherif, Izabela Naydenova, Suzanne Martin, Colm Mcginn, G Berger, C Denz, Vincent Toal

Conference Papers

An acrylamide-based photopolymer formulated in the Centre for Industrial and Engineering Optics has been investigated with a view to further optimisation for holographic optical storage. Series of 15 to 30 gratings were angularly multiplexed in a volume of the photopolymer layers with different thickness at a spatial frequency of 1500 lines/mm. Since the photopolymer is a saturable material, an exposure scheduling method was used to exploit the entire dynamic range of the material and allow equal strength gratings to be recorded. From this investigation the photopolymer layer’s M/# was determined with regard to the recording geometry used. The temporal stability …


Holographic Recording Of Patterns In Thin Film Acrylamide-Based Photopolymer, Izabela Naydenova, Kotakonda Pavani, Emilia Mihaylova, Katia Loudmer, Suzanne Martin, Vincent Toal Jan 2005

Holographic Recording Of Patterns In Thin Film Acrylamide-Based Photopolymer, Izabela Naydenova, Kotakonda Pavani, Emilia Mihaylova, Katia Loudmer, Suzanne Martin, Vincent Toal

Conference Papers

A study of the light induced surface relief modulation in thin photopolymer layers is reported. Due to the nature of the photopolymer used no additional post-processing is required after holographic recording. An investigation of the dependence of the amplitude of the photoinduced relief modulation on different parameters of recording such as spatial frequency, intensity of the beams and times of exposure has been carried out. The surface relief modulation is characterized by white light interferometry. Photopolymer layer thickness ranges from 1-5m. A model of the mechanism of surface relief formation is proposed on the basis of the measured dependencies. A …


Expert Testimony In Capital Sentencing: Juror Responses, John H. Montgomery, J. Richard Ciccone, Stephen P. Garvey, Theodore Eisenberg Jan 2005

Expert Testimony In Capital Sentencing: Juror Responses, John H. Montgomery, J. Richard Ciccone, Stephen P. Garvey, Theodore Eisenberg

Cornell Law Faculty Publications

The U.S. Supreme Court, in Furman v. Georgia (1972), held that the death penalty is constitutional only when applied on an individualized basis. The resultant changes in the laws in death penalty states fostered the involvement of psychiatric and psychologic expert witnesses at the sentencing phase of the trial, to testify on two major issues: (1) the mitigating factor of a defendant’s abnormal mental state and (2) the aggravating factor of a defendant’s potential for future violence. This study was an exploration of the responses of capital jurors to psychiatric/psychologic expert testimony during capital sentencing. The Capital Jury Project is …


Death Sentence Rates And County Demographics: An Empirical Study, Theodore Eisenberg Jan 2005

Death Sentence Rates And County Demographics: An Empirical Study, Theodore Eisenberg

Cornell Law Faculty Publications

The number of murders in a state largely determines the size of a state's death row. The more murders, the larger the death row. This fundamental relation yields surprising results, including the newsworthy finding that Texas's death sentencing rate is not unusually high. Recent state-level research also underscores the importance of race in the demography of death row. Death penalty research has long emphasized race's role, and with good reason--a racial hierarchy exists in death sentence rates. Black defendants who murder white victims receive death sentences at the highest rate; white defendants who murder white victims receive death sentences at …


Identification And Recovery Of An Asymmetric Calix[4]Arene Tetranitrile Derivative Using Liquid Chromatography And Mass Spectrometry, Benjamin Schazmann, Dermot Diamond Jan 2005

Identification And Recovery Of An Asymmetric Calix[4]Arene Tetranitrile Derivative Using Liquid Chromatography And Mass Spectrometry, Benjamin Schazmann, Dermot Diamond

Articles

A simple analytical LC-MS (Liquid Chromatography Mass Spectrometry) method and associated instrumentation has been adapted for use by the organic chemist to yield mg quantities of target compound from a reaction mixture. Calix[4]arene 3 was identified as representing 51% of total peak area of a reaction mixture containing no less than 10 components, using LC-MS. This peak corresponded to a mass of 878.8, equivalent to a complex of 3 and an ammonium cation. Molecular models further rationalise this observation by showing that the asymmetric binding cavity of 3 is suitable for binding tetrahedral guests like the ammonium ion. By scaling …


Geospatial Analysis Of Gravel Bar Deposition And Channel Migration Within The Ozark National Scenic Riverways, Missouri (1955-2003), Derek J. Martin Jan 2005

Geospatial Analysis Of Gravel Bar Deposition And Channel Migration Within The Ozark National Scenic Riverways, Missouri (1955-2003), Derek J. Martin

MSU Graduate Theses

Historical land clearing is believed to be responsible for present-day channel instability in main stem reaches in the Ozark National Scenic Riverways (ONSR) in south-central Missouri. The nature of instability is related to the delivery of excess amounts of gravel sediment to stream channels and higher rates of lateral bank erosion. These conditions are of concern to resource managers because of the potential damaging effects on recreational facilities and aquatic habitat. The purpose of this study is to develop a geographic information systems (GIS)/remote sensing (RS) based methodology to monitor spatial patterns of gravel deposition and lateral channel migration within …


Numerical Simulation Of Double‐Diffusive Finger Convection, Joseph D. Hughes, Ward E. Sanford, H. L. Vacher Jan 2005

Numerical Simulation Of Double‐Diffusive Finger Convection, Joseph D. Hughes, Ward E. Sanford, H. L. Vacher

School of Geosciences Faculty and Staff Publications

A hybrid finite element, integrated finite difference numerical model is developed for the simulation of double‐diffusive and multicomponent flow in two and three dimensions. The model is based on a multidimensional, density‐dependent, saturated‐unsaturated transport model (SUTRA), which uses one governing equation for fluid flow and another for solute transport. The solute‐transport equation is applied sequentially to each simulated species. Density coupling of the flow and solute‐transport equations is accounted for and handled using a sequential implicit Picard iterative scheme. High‐resolution data from a double‐diffusive Hele‐Shaw experiment, initially in a density‐stable configuration, is used to verify the numerical model. The temporal …


Cmodels For Tight Disjunctive Logic Programs, Yuliya Lierler Jan 2005

Cmodels For Tight Disjunctive Logic Programs, Yuliya Lierler

Computer Science Faculty Proceedings & Presentations

Disjunctive logic programming under the stable model semantics [GL91] is a new answer set programming (ASP) methodology for solving combinatorial search problems. It is a form of declarative programming related to logic programming languages, such as Prolog, where the solutions to a problem are represented by answer sets, and not by answer substitutions produced in response to a query as in convential logic programming. Instead of Prolog systems, this programming method uses answer set solvers, such as smodels1, smodelscc2, cmodels3, dlv4, and gnt1. These systems made it possible for ASP to be successfully applied in such areas as planning, bounded …


Disjunctive Answer Set Programming Via Satisfiability, Yuliya Lierler Jan 2005

Disjunctive Answer Set Programming Via Satisfiability, Yuliya Lierler

Computer Science Faculty Proceedings & Presentations

Using SAT solvers as inference engines in answer set programming systems showed to be a promising approach in building efficient systems. Nowadays SAT based answer set programming systems successfully work with nondisjunctive programs. This paper proposes a way to use SAT solvers for finding answer sets for disjunctive logic programs. We implement two different ways of SAT solver invocation used in nondisjunctive answer set programming. The algorithms are based on the definition of completion for disjunctive programs and the extension of loop formula to the disjunctive case. We propose the necessary modifications to the algorithms known for nondisjunctive programs in …


Development Of The Maryland Shoreline Inventory Methods And Guidelines For Anne Arundel County - Gis Data, Marcia Berman, Harry Berquist, Sharon Killeen, Karinna Nunez, Karen Reay, Tamia Rudnicky, Daniel E. Schatt, David Weiss Jan 2005

Development Of The Maryland Shoreline Inventory Methods And Guidelines For Anne Arundel County - Gis Data, Marcia Berman, Harry Berquist, Sharon Killeen, Karinna Nunez, Karen Reay, Tamia Rudnicky, Daniel E. Schatt, David Weiss

Data

The Center for Coastal Resources Management (CCRM) at the Virginia Institute of Marine Science (VIMS) has generated Shoreline Situation Reports (SSRs) for coastal localities in the state of Maryland. This effort compliments a parallel effort in Virginia by the same group. SSRs were developed by VIMS in the 1970s for Virginia and have been the foundation for shoreline management planning in Tidewater Virginia ever since. CCRM has developed new protocols for collecting, disseminating, and reporting data relevant to shoreline management issues using state of the art mapping and remote sensing techniques. New SSRs are being generated on a county by …


Synthetic Studies In Phytochrome Chemistry, Peter A. Jacobi, Imad Odeh, Subhas Buddhu, Guolin Cai, Sundaramoorthi Rajeswari, Douglas Fry, Wanjun Zheng, Robert W. Desimone, Jiasheng Guo, Lisa D. Coutts, Sheila I. Hauck, Sam H. Leung, Indranath Ghosh, Douglas Pippin Jan 2005

Synthetic Studies In Phytochrome Chemistry, Peter A. Jacobi, Imad Odeh, Subhas Buddhu, Guolin Cai, Sundaramoorthi Rajeswari, Douglas Fry, Wanjun Zheng, Robert W. Desimone, Jiasheng Guo, Lisa D. Coutts, Sheila I. Hauck, Sam H. Leung, Indranath Ghosh, Douglas Pippin

Dartmouth Scholarship

An account is given of the author’s several approaches to the synthesis of the parent chromophore of phytochrome (1), a protein-bound linear tetrapyrrole derivative that controls photomorphogenesis in higher plants. These studies culminated in enantioselective syntheses of both (2R)- and (2S)-phytochromobilin (4), as well as several 13C-labeled derivatives designed to probe the site of Z,E-isomerization during photoexcitation. When reacted in vitro, synthetic 2R-4 and recombinant-derived phytochrome apoprotein N-C produced a protein-bound chromophore with identical difference spectra to naturally occurring 1.


The Kerf Toolkit For Intrusion Analysis, Javed Aslam, Sergey Bratus, David Kotz, Ronald Peterson Jan 2005

The Kerf Toolkit For Intrusion Analysis, Javed Aslam, Sergey Bratus, David Kotz, Ronald Peterson

Dartmouth Scholarship

No abstract provided.


Reevaluation Of Species Concepts Of Uppermost Cretaceous Unionidae (Mollusca: Bivalvia) : Hell Creek Formation, Montana, U.S.A., Marron J. Bingle Jan 2005

Reevaluation Of Species Concepts Of Uppermost Cretaceous Unionidae (Mollusca: Bivalvia) : Hell Creek Formation, Montana, U.S.A., Marron J. Bingle

Theses and Dissertations

Species are the basic units of life relative to taxonomy, and a practical definition of species is imperative to paleontology in order to promote reproducible, unambiguous criteria for accurately interpreting past species relationships. The need for a well-defined rubric for identifying species is evident in the freshwater mussel assemblage (Family Unionidae) in the Hell Creek Formation. The Hell Creek Formation unionid species were first described by Whitfield in 1903 and 1907. His descriptions were often based on differences of a single trait. In 197 6, Russell reevaluated the original species descriptions, I but still based the classification of species on …


ข่าว& กิจกรรมสิ่งแวดล้อม Jan 2005

ข่าว& กิจกรรมสิ่งแวดล้อม

Thai Environment

No abstract provided.