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Quantitative Ftir Analysis Of Gas Phase Cigarette Smoke., Rafael Cueto Jan 1990

Quantitative Ftir Analysis Of Gas Phase Cigarette Smoke., Rafael Cueto

LSU Historical Dissertations and Theses

A new method, using Fourier transform infrared spectroscopy (FTIR), was developed for the simultaneous determination of nitrogen dioxide and nitric oxide in gas phase cigarette smoke and in model systems. The FTIR method also allows the simultaneous determination of other components. The method uses multivariate least-squares regression analysis, that allows simultaneous quantitation of several components even in the presence of overlapping peaks, and fast data acquisition for kinetic analysis. For the preparation of the gas mixtures an apparatus that uses mass flow controllers, check-valves, and ground glass joints was constructed. This apparatus gives very exact metering, allowing the preparation of …

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Computational Neural Learning Formalisms For Perceptual Manipulation: Singularity Interaction Dynamics Model., Sandeep Gulati Jan 1990

Computational Neural Learning Formalisms For Perceptual Manipulation: Singularity Interaction Dynamics Model., Sandeep Gulati

LSU Historical Dissertations and Theses

This dissertation addresses a fundamental problem in computational AI--developing a class of massively parallel, neural algorithms for learning robustly, and in real-time, complex nonlinear transformations from representative exemplars. Provision of such a capability is at the core of many real-life problems in robotics, signal processing and control. The concepts of terminal attractors in dynamical systems theory and adjoint operators in nonlinear sensitivity theory are exploited to provide a firm mathematical foundation for learning such mappings with dynamical neural networks, while achieving a dramatic reduction in the overall computational costs. Further, we derive an efficient methodology for handling a multiplicity of …

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Chromatographic Peak Shape Analysis And Modeling., Mark Stephen Jeansonne Jan 1990

Chromatographic Peak Shape Analysis And Modeling., Mark Stephen Jeansonne

LSU Historical Dissertations and Theses

Various aspects of chromatographic peak quantitation and shape characterization are investigated in detail for single and overlapping chromatographic peaks. From the viewpoint of providing better quantitation of real chromatographic data while minimizing computational complexity, the results presented should be easily incorporated into existing routine chromatographic data analysis regimes. Three topics applicable to modern chromatographic data analysis are considered. First, progress in the application of the exponentially modified Gaussian (EMG) function to chromatography is reviewed. The review covers the following areas: (1) equations derived from the model, (2) studies of inherent errors in the quantitation of chromatographic peaks via use of …

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Genetic Comparisons And Systematic Studies Of Termites (Isoptera)., Amy Kathryn Korman Jan 1990

Genetic Comparisons And Systematic Studies Of Termites (Isoptera)., Amy Kathryn Korman

LSU Historical Dissertations and Theses

Eusociality has evolved in only two insect orders: the Isoptera and Hymenoptera. While hymenopteran genetics has been the subject of intensive study, genetic information on termites is conspicuously lacking. The purpose of this dissertation was to utilize starch gel electrophoresis in genetic studies of termites. Chapter I consists of electrophoretic methods and a study of genetic variability among four families of termites. Although some representative species/colonies demonstrated low levels of variation, the ranges of polymorphic loci and gene diversity were within levels generally observed for the class Insecta. Levels of genetic variation exhibited by termites were higher than those values …

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Gas Kick Behavior During Well Control Operations In Vertical And Slanted Wells., Edson Yoshihito Nakagawa Jan 1990

Gas Kick Behavior During Well Control Operations In Vertical And Slanted Wells., Edson Yoshihito Nakagawa

LSU Historical Dissertations and Theses

An experimental study for the determination of the gas fraction and gas velocity in the mud during gas kick control operations was performed. It consisted of two-phase flow of gas-water and gas-mud mixtures through a 14 m (46 ft) fully eccentric annular section of an experimental apparatus. The inclination from the vertical position was varied from 0$\sp\circ$ to 80$\sp\circ$. The results from these tests allowed the evaluation of a previous model for gas bubbles in vertical wells. They also provided support for modifications of that model concerning two aspects: extending its application to slanted wells and improving the simulation in …

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Attributions Of Teachers And Students In Middle School Science Classrooms., Lennie Holomon Rhys Jan 1990

Attributions Of Teachers And Students In Middle School Science Classrooms., Lennie Holomon Rhys

LSU Historical Dissertations and Theses

The purpose of the present study was to examine: (a) teachers' notions about their students, (b) students' notions about themselves and learning, and (c) important factors that characterize, and possibly influence, these notions. The investigation was based on attribution theory, which proposes a framework for ascribing causes of a person's behavior, given that person's belief system. In this study, five notions, or attributions, were specified: attachment, concern, satisfied, indifferent, and rejection, and were expressed in three forms: oral, written, and behavioral. Subjects included three sixth-grade science teachers, three eighth-grade science teachers, and one science class from each teacher's schedule. For …

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The Spectroscopy Of Vapor Phase Benzaldehyde And Distant Intercellular Interactions Of Chick Embryo Fibroblast Cell Cultures., Vestel Bryan Shirley Jan 1990

The Spectroscopy Of Vapor Phase Benzaldehyde And Distant Intercellular Interactions Of Chick Embryo Fibroblast Cell Cultures., Vestel Bryan Shirley

LSU Historical Dissertations and Theses

Spectra in different regions of the electromagnetic spectrum were taken at different temperatures for benzaldehyde vapor. A review of the literature revealed that the existing data could not be interpreted by this model. Possible perturbations were reviewed. Potential models based on these perturbations were proposed. Calculations were carried out to test the interpretation. No disagreement between experimental and computational findings resulted. The models proposed contradicted no existing experimental determination of the ground state of vapor phase benzaldehyde. It was determined that electron and neutron diffraction experiments were necessary to determine the ground state structure of benzaldehyde. If the results show …

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Canonical Commutator And Mass Renormalization, G. W. Ford, R. F. O'Connell Nov 1989

Canonical Commutator And Mass Renormalization, G. W. Ford, R. F. O'Connell

Faculty Publications

The question considered is the effect on the canonical commutation rules of mass renormalization in quantum electrodynamics. This is investigated by considering the quantum Langevin equation for a charged quantum oscillator interacting with the radiation field via dipole interaction. Explicit expressions for the commutator are obtained for finite cutoff frequency as well as the large-cutoff limit. The surprising result obtained is that the exactly equal-time (canonical) commutator involves the bare mass, while the corresponding commutator for infinitesimally displaced times involves the renormalized mass. © 1989 Plenum Publishing Corporation.

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Erratum, John C. Larkin, Paul A. Lefebvre, Carolyn D. Silflow Aug 1989

Erratum, John C. Larkin, Paul A. Lefebvre, Carolyn D. Silflow

Faculty Publications

No abstract provided.

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Louisiana Agriculture Magazine, Summer 1989, Lsu Agricultural Experiment Station Jul 1989

Louisiana Agriculture Magazine, Summer 1989, Lsu Agricultural Experiment Station

Louisiana Agriculture

No abstract provided.

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Louisiana Agriculture Magazine, Spring 1989, Lsu Agricultural Experiment Station Apr 1989

Louisiana Agriculture Magazine, Spring 1989, Lsu Agricultural Experiment Station

Louisiana Agriculture

No abstract provided.

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Polarized Radiation From Inhomogeneous Shocks., Kinwah Wu Jan 1989

Polarized Radiation From Inhomogeneous Shocks., Kinwah Wu

LSU Historical Dissertations and Theses

Strongly polarized radiation from AM Herculis binaries is believed to be due to cyclotron emission from hot magnetized plasmas. The flat optically thin spectra and strong IR polarization observed in these binaries cannot be explained by models assuming a homogeneous emission region with a simple geometry. We have therefore studied the cyclotron emission from infinite plasma cylinders with uniform magnetic fields and temperatures, but with a variety of axially symmetric electron density profiles and shown that such inhomogeneous plasmas are able to produce relatively flat spectra which cannot be produced by the homogeneous models. The polarization at low frequencies is …

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Adolescent Alcohol Expectancies And Alcohol Use As Functions Of Familial Factors., Andrew Ward Millar Jan 1989

Adolescent Alcohol Expectancies And Alcohol Use As Functions Of Familial Factors., Andrew Ward Millar

LSU Historical Dissertations and Theses

In an extension of Brown, Creamer and Stetson (1987), this study investigated the relationships between components of family life, adolescent drinking and alcohol expectancies. Alcohol expectancies are defined as the learned associations between alcohol consumption and the results of drinking. Out of 73 adolescent (12- to 18-year old) subjects screened, 55 met criteria and participated in two comparisons with multiple dependent variables. In the first of these, 15 subjects who were exposed to alcoholics for at least 75% of their lives were found to have stronger expectations that alcohol would provide cognitive and motor enhancement than did 15 matched subjects …

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Using Expert Systems In Maintenance Monitoring And Management., Tahoomars Rastin Jan 1989

Using Expert Systems In Maintenance Monitoring And Management., Tahoomars Rastin

LSU Historical Dissertations and Theses

In this research, a model for fault diagnosis of equipment is discussed. The model discusses the use of multi-variable monitoring for a more precise means of equipment malfunction trouble shooting. Also within this model means are discussed for automatically generating work-orders. Equipments are divided into subsystems. The subsystems are broken down into sub-subgroups and further down to individual parts. Preventive maintenance techniques, along with expert system technology, are used to develope the maintenance expert system (MES). Statistical pattern recognition techniques are used as a way to describe the relationship between categories of equipment. The relationships shown here are mostly that …

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Determination Of The Wavelength Dependence Of The Optical Properties Of Soot From In-Situ Measurements., Hyunsoo Chang Jan 1989

Determination Of The Wavelength Dependence Of The Optical Properties Of Soot From In-Situ Measurements., Hyunsoo Chang

LSU Historical Dissertations and Theses

The index of refraction of soot particles is of considerable importance in many areas of research and engineering applications such as combustion diagnostics and radiative transfer from combustion systems. The present study aims toward the analysis of compositional effect on the refractive index and the spectral variation of the indices of soot particles by combining classical and dynamic light scattering measurements with the Kramers-Kronig relations in hydrocarbon flames. The particle size distribution is determined from photon correlation measurements. The number densities, volume fractions and refractive indices are then determined as a function of the height above the burner and fuel …

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Development Of A Karplus-Type Relationship For Solid State Deuterium Nuclear Magnetic Resonance Spectroscopy., Margaret Alice Callaghan Jackisch Jan 1989

Development Of A Karplus-Type Relationship For Solid State Deuterium Nuclear Magnetic Resonance Spectroscopy., Margaret Alice Callaghan Jackisch

LSU Historical Dissertations and Theses

This dissertation is the first application of a Karplus-type relationship to solid-state deuterium NMR spectroscopy. In particular zero-field high-resolution deuterium adiabatic demagnetization in the laboratory frame (ADLF) spectroscopy has been used to distinguish between two inequivalent deuterium positions in alpha substituted arylacetic acids. High resolution spectra with linewidths of 1-2 kHz were observed and have been used successfully to document the inequivalent positions both by single and double transition spectra. Further, small applied fields, inducing Zeeman splitting, have proven the deuterons observed to be from the transition frequencies of two different deuterons. Individual spectra are shown for all compounds included …

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An Empirical Investigation Of The Financial Statement Characteristics Of Firms Engaging In In-Substance Defeasance Of Debt., Raymond Jeffords Jr Jan 1989

An Empirical Investigation Of The Financial Statement Characteristics Of Firms Engaging In In-Substance Defeasance Of Debt., Raymond Jeffords Jr

LSU Historical Dissertations and Theses

Extinguishment of debt through in-substance defeasance is a powerful debt management tool that enables corporations to eliminate debt from their balance sheets and record substantial gains on extinguishment whenever market rates of interest exceed the coupon rate of defeased debt. Corporations engaging in in-substance defeasance must conform to the provision of Statement of Financial Accounting Standards No. 76, Extinguishment of Debt, issued by the Financial Accounting Standards Board in 1983. Critics of Statement No. 76 charge that in-substance defeasance may be used to window dress the financial statements. This study represents an initial test of the assertion that in-substance defeasance …

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An Experimental Research Study On The Effect Of Accrual Of Nonpension Postretirement Benefit Costs On Loan Officers' Decisions., Joyce Ann Strawser Jan 1989

An Experimental Research Study On The Effect Of Accrual Of Nonpension Postretirement Benefit Costs On Loan Officers' Decisions., Joyce Ann Strawser

LSU Historical Dissertations and Theses

On February 14, 1989, the Financial Accounting Standards Board issued an exposure draft entitled "Employers' Accounting for Postretirement Benefits Other Than Pensions." The provisions of this proposed Statement of Financial Accounting Standards would require that the costs of nonpension postretirement benefits be recognized in employer financial statements over the service lives of employees expected to receive benefits. This study examined the decisions of commercial bank loan officers in an experiment designed to determine whether the proposed accrual of postretirement health care benefits affects the decisions of financial statement users. The following issues were also addressed: (1) Does the nonpension postretirement …

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Overestimation Of Basis Set Superposition Error In Molecular Dimer Correlation Potential Energy Calculations., Jia-An Yang Jan 1989

Overestimation Of Basis Set Superposition Error In Molecular Dimer Correlation Potential Energy Calculations., Jia-An Yang

LSU Historical Dissertations and Theses

It is important to remove the basis set superposition error (BSSE) from the intermolecular potential energy calculations with the counterpoise (CP) correction especially for weak intermolecular interactions. However, it has been still questioned whether the counterpoise (CP) correction overestimates the real BSSE. To answer this question is the purpose of this research. In this study, the overestimation of basis set superposition error (BSSE) by the counterpoise (CP) method has been analyzed by an approach called "localized orbital pair correlation". This approach is able to eliminate the overestimation of basis set superposition error (BSSE) for the second order potential energies. Prototype …

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An Experiment To Study The Effects Of Changing Format And Scaling Characteristics Of Financial Statement Data., Paul Michael Goldwater Jan 1989

An Experiment To Study The Effects Of Changing Format And Scaling Characteristics Of Financial Statement Data., Paul Michael Goldwater

LSU Historical Dissertations and Theses

Current financial statements present single numbers, the result of a measurement process embracing many estimates and arbitrary classifications, summarizations, judgments, and allocations. These point-estimates and the ensuing uncertainty for decisionmakers has been cause for concern to both academics and practitioners, evoking various recommendations to change the format and scaling of financial statement data. The most significant acknowledgment of this problem came from the Financial Accounting Standards Board in 1978, when it released Objectives of Financial Reporting by Business Enterprises (SFAC No. 1). The primary interest of this research was to study the impact on decisionmaking about prospective cash flows by …

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Gongora's "Soledades" As A Problem Of Language And Meaning In Seventeenth Century Spain., Ted Eustace Mcvay Jr Jan 1989

Gongora's "Soledades" As A Problem Of Language And Meaning In Seventeenth Century Spain., Ted Eustace Mcvay Jr

LSU Historical Dissertations and Theses

The exploration of the epistemological assumptions necessary for the interpretation of Luis de Gongora's "Soledades" is an area of critical attention that has gone virtually neglected since his 1927 "rehabilitation." This study offers an approach to understanding the long, difficult poem and the bitter critical reaction against it in the context of the seventeenth-century shift of predominant epistemologies discussed by Michel Foucault in The Order of Things. An approach that focuses on how the world is known is most appropriate to a study of the "Soledades" for several reasons, one being that those writers who attacked the poem did so …

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Harmonic Measurement And Reduction In Power Systems., Rutisurhata Kurniawan Hartana Jan 1989

Harmonic Measurement And Reduction In Power Systems., Rutisurhata Kurniawan Hartana

LSU Historical Dissertations and Theses

Harmonic voltages and currents are created by nonlinear loads in power systems. These harmonics can cause serious problems to the energy suppliers (utility companies) and energy users (consumers). This dissertation presents new techniques for harmonic measurement and the accompanying problem, harmonic reduction. To reduce harmonics, the location and magnitude of harmonic sources must be known a priori. However, to measure and monitor harmonic sources requires specialized instrumentation that is not generally permanently installed at most buses. In this study, a method is developed to use neural networks in conjunction with state estimation for monitoring and estimating harmonic sources with only …

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Theoretical And Numerical Models For Heat And Mass Transport And Groundwater Flow Near Salt Domes., David Griffin Evans Jan 1989

Theoretical And Numerical Models For Heat And Mass Transport And Groundwater Flow Near Salt Domes., David Griffin Evans

LSU Historical Dissertations and Theses

Groundwater near salt domes is an inherently complex hydrogeologic system because groundwater is subject to large lateral gradients in salinity and temperature. Moreover, groundwater flow is indirectly coupled to salt tectonics because diapirism alters the salinity and thermal conditions as a sedimentary basin evolves. In order to study this complex environment, mathematical and numerical models are developed which explicitly couple heat and dissolved salt transport to groundwater flow, and account for basin subsidence and salt diapirism. The groundwater flow field is described using a mass stream function which does not require the Boussinseq assumption. The numerical model uses a control …

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Development And Field Applications Of Shaly Sand Petrophysical Models., Milton Noel Lau Jan 1989

Development And Field Applications Of Shaly Sand Petrophysical Models., Milton Noel Lau

LSU Historical Dissertations and Theses

A new, theoretically derived model expressing shaly sand conductivity is presented. The proposed model is based on dual water and cation exchange capacity concepts. The new model is based on the Waxman and Smits concept of supplementing the water conductivity with a clay counterions conductivity. The model also utilizes the dual water theory, which relates each conductivity term to a particular type of water, each occupying a specific volume of the total pore space. The proposed model, however, assumes that the counterion conductivity can be represented by a hypothetical electrolyte. The properties of this electrolyte were derived from electrochemical and …

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Analytical Studies Of Wireline Formation Testing And Pressure Losses Across Gravel Packs., Turhan Yildiz Jan 1989

Analytical Studies Of Wireline Formation Testing And Pressure Losses Across Gravel Packs., Turhan Yildiz

LSU Historical Dissertations and Theses

A three-dimensional (3-D) analytical model was developed to improve the analyses of the transient pressure response of a reservoir to wireline formation testing (WFT). Available analysis techniques of the WFT oversimplify the flow geometry by assuming either a radial or a spherical flow pattern. The proposed model simulates the exact flow geometry of the WFT flow pattern. The model was derived by solving the 3-D diffusivity equation coupled with the boundary conditions prevailing during the test. The Laplace transformation and the separation of variables were used to obtain the solution. The solution is expressed in terms of the infinite Fourier-Bessel …

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The Biosynthesis Of The Chromophore Of Phycocyanin. Pathway Of Reduction Of Biliverdin To Phycocyanobilin., S. B. Brown, J. A. Holroyd, D. I. Vernon, Y. K. Shim, K. M. Smith Jan 1989

The Biosynthesis Of The Chromophore Of Phycocyanin. Pathway Of Reduction Of Biliverdin To Phycocyanobilin., S. B. Brown, J. A. Holroyd, D. I. Vernon, Y. K. Shim, K. M. Smith

Faculty Publications

The later stages in the pathway of biosynthesis of phycocyanobilin, the chromophore of phycocyanin, were studied by using radiolabelled intermediates. Three possible pathways from biliverdin IX-alpha to phycocyanobilin were considered. 14C-labelled samples of key intermediates in two of the pathways, 3-vinyl-18-ethyl biliverdin IX-alpha and 3-ethyl-18-vinyl biliverdin IX-alpha, were synthesized chemically and were administered to cultures of Cyanidium caldarium that were actively synthesizing photosynthetic pigments in the light. Neither of these two compounds was apparently incorporated into the phycobiliprotein chromophore, suggesting that two of the three pathways were not operative. By elimination, the results imply that the third possible pathway, which …

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Efficacy Of Phospholipid Analysis In Determining Microbial Biomass In Sediments, R. H. Findlay, G. M. King, L. Watling Jan 1989

Efficacy Of Phospholipid Analysis In Determining Microbial Biomass In Sediments, R. H. Findlay, G. M. King, L. Watling

Faculty Publications

Improvements in the analysis of lipid-bound phosphates resulted in a simplified and sensitive method for determining microbial biomass in sediments. Sensitivity was enhanced over previous methods by use of a dye, malachite green, which when complexed with phosphomolybdate at low pH has a high extinction coefficient (at 610 nm). The use of a persulfate oxidation technique to liberate phosphate from lipids increased the simplicity and safety of the method relative to the traditional perchloric acid digestions. The modified method was both accurate (yielding quantitative recoveries of cells added to sediments) and precise (coefficient of variation of less than 5% for …

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Factors Affecting Supervisors' Use Of Corrective Actions Following Poor Performance., Wanda Ann Trahan Jan 1989

Factors Affecting Supervisors' Use Of Corrective Actions Following Poor Performance., Wanda Ann Trahan

LSU Historical Dissertations and Theses

The present study examined the relationships between supervisor, subordinate, and contextual variables and corrective action severity. Hypotheses were tested using questionnaire data from 103 nursing supervisors in 15 hospitals. Supervisors were asked to describe an incident of subordinate poor performance, indicate the corrective action used, then complete questions measuring incident severity, attributions, initiating structure and consideration leader styles, intent of the supervisor, effectiveness ratings of the corrective action, influence of contextual variables, and subordinate likableness. Analyses confirmed that severity of the incident of poor performance, supervisor attributions, and supervisor intent were related to corrective action severity. Also, corrective actions rated …

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On The Pierce-Birkhoff Conjecture Over Ordered Fields, Charles N. Delzell Jan 1989

On The Pierce-Birkhoff Conjecture Over Ordered Fields, Charles N. Delzell

Faculty Publications

No abstract provided.

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Reference Standards For Flow Cytometry And Application In Comparative Studies Of Nuclear Dna Content, Terrence R. Tiersch, Robert W. Chandler, Stephen S. Wachtel, Sherman Elias Jan 1989

Reference Standards For Flow Cytometry And Application In Comparative Studies Of Nuclear Dna Content, Terrence R. Tiersch, Robert W. Chandler, Stephen S. Wachtel, Sherman Elias

Faculty Publications

Nuclear DNA mass in cells from a reference species can be used to obtain high‐resolution estimates of DNA mass from a target species. In our study of DNA mass in cells from 45 selected species, representing each of the major vertebrate classes, we have obtained values of from 1.5 to 110.0 pg of DNA. Because values in or near this range would be expected in the study of nuclear DNA mass in vertebrates and other organisms, the species in this report can provide a useful catalogue of references for comparative studies of DNA. Copyright © 1989 Wiley‐Liss, Inc.

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