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Techniques For Resolving Incomplete Systems In K-Systems Analysis., Gary J. Asmus Jan 1998

Techniques For Resolving Incomplete Systems In K-Systems Analysis., Gary J. Asmus

LSU Historical Dissertations and Theses

K-systems analysis is a generalization of reconstructability analysis (RA), where any general, complete multivariate system (g-system) can be transformed into an isomorphic, dimensionless system (a K-system) that has sufficient properties to be analyzed using probabilistic RA algorithms. In particular, a g-system consists of a set of states formed from a complete combination of the variables assigned specific values from a finite set of possible values and an associated system function value. The g-system must be complete in that all possible states must have an associated system function value. K-systems analysis has been applied to a variety of systems, but many …

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A Cross-Site Inquiry Into Reading Instruction In Differentially Successful Title I Schools., Gypsye Dugas Bryan Jan 1998

A Cross-Site Inquiry Into Reading Instruction In Differentially Successful Title I Schools., Gypsye Dugas Bryan

LSU Historical Dissertations and Theses

By design, elementary schools are places where students perform specified tasks and become literate. In practice, elementary schools enroll students who engage in instructional activity, yet many of these students fail to reach minimum literacy standards. This multiple-case qualitative inquiry focused on the inner workings of schools where students placed at risk learned to read and examined schools where similar students did not learn to read. Research conducted in four elementary schools addressed the following questions: (a) What resources, time factors, and management systems do elementary teachers use to create an effective reading environment? (b) How do reading assessment measures …

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Pressure-Induced Changes In Structural And Mechanical Properties Of Gallium Arsenide And Nanophase Silicon Carbide Using Parallel Molecular Dynamics Simulations., Alok Chatterjee Jan 1998

Pressure-Induced Changes In Structural And Mechanical Properties Of Gallium Arsenide And Nanophase Silicon Carbide Using Parallel Molecular Dynamics Simulations., Alok Chatterjee

LSU Historical Dissertations and Theses

Large-scale parallel molecular-dynamics (MD) simulations are performed to investigate properties and processes in nanophase silicon carbide (n-SiC) and gallium arsenide (GaAs) under pressure. These simulations involve 10 6 atoms interacting via realistic interatomic potentials. Structure and sintering of crystalline n-SiC are also investigated with neutron scattering experiments performed at the Intense Pulsed Neutron Source Division (IPNS), Argonne National Laboratory. Both MD simulations and neutron scattering experiments indicate the onset of sintering around 1500K. During sintering, the pores shrink in size while maintaining their morphology: Their fractal dimension remains ∼2.4 and their surface roughness exponent is ∼0.45. The pair distribution functions …

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Evangelical Communication: Reference Group Membership Influence On Message Interpretation And Public Opinion., Mary Diane Hollems Jan 1998

Evangelical Communication: Reference Group Membership Influence On Message Interpretation And Public Opinion., Mary Diane Hollems

LSU Historical Dissertations and Theses

The purpose of the present dissertation was to examine the influence of reference group membership on message interpretation and whether one's interpretation then influences one's agreement with the message source and subsequent willingness to speak with the message source about the topic. In particular, this study looked at conservative Christian reference group membership and message interpretations about the topic of abortion. The independent variables of level of Christian fundamentalism, involvement in a Christian reference group, and socio-political conservatism were averaged to create a conservative fundamentalist composite score which was then used to split the sample at the median. Findings indicated …

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Influence Of Diet And Genetic Strain On Desirable Flavors In Farm-Raised Catfish., Carol Ann Kelly Jan 1998

Influence Of Diet And Genetic Strain On Desirable Flavors In Farm-Raised Catfish., Carol Ann Kelly

LSU Historical Dissertations and Theses

This farm-raised catfish quality study measured desirable flavor attributes, Chickeny, Nutty, Fat Complex, Corn, Sweet, with the objective to determine effects of feed ingredients, time-on-diet and genetic strain. Overall flavor impact differences were tested by triangle tests. The diets were Casein-base reference feed by itself or partially substituted with: 10% catfish meal, 10% meat and bone meal, 10% rice bran, or 3% menhaden oil and commercial feed formulation. Fish were grown indoors to minimize environmental flavors for 70, 160, 210 and 318 days. The genetic strains evaluated were channel, albino channel, blue, hybrid channel x blue, and black bullhead catfish. …

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Redefining Babes, Booze And Brawls: Men Against Violence. Towards A New Masculinity., Luoluo Hong Jan 1998

Redefining Babes, Booze And Brawls: Men Against Violence. Towards A New Masculinity., Luoluo Hong

LSU Historical Dissertations and Theses

Despite evidence that 90% of violent crimes are committed by men, higher education professionals and researchers still understand relatively little about the process by which mate students acquire the attitudes, knowledge, values and skills which serve as deterrents to perpetrating violence against women and against other men. Men Against Violence is a peer advocacy organization at a large, public Research I institution in the South which focuses on the special and unique responsibility men have to end violence. Through participation in a wide array of service learning, community action and leadership opportunities, MAV members challenge cultural norms which link masculinity …

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The Effects Of Autocorrelation In The Estimation Of Process Capability Indices., Lawrence Lee Magee Jan 1998

The Effects Of Autocorrelation In The Estimation Of Process Capability Indices., Lawrence Lee Magee

LSU Historical Dissertations and Theses

The current popularity of the process capability index, a measure of a supplier's ability to meet the product specifications demanded by a customer, has become a matter of some controversy. While admitting the validity of much existing criticism, this research demonstrates that sample estimation of the triple index (Cpl, Cp, Cpu), a variant of the widely used index pair (Cp, Cpk), is equivalent to estimation of the natural parameters (mu, sigma) whenever the measured process characteristic X has an unconditional (marginal) normal probability density function. This includes processes which obey the strictly stationary, normal ARMA( p, q) model. By this …

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Factors Determining University Enrollment Status: The Case Of High School Students Recruited To Attend Louisiana State University College Of Agriculture., Fredrick Muyia Nafukho Jan 1998

Factors Determining University Enrollment Status: The Case Of High School Students Recruited To Attend Louisiana State University College Of Agriculture., Fredrick Muyia Nafukho

LSU Historical Dissertations and Theses

The purpose of this study was to determine whether a model existed that significantly increased the researcher's ability to accurately explain whether or not a recruited student in the College of Agriculture at LSU will enroll based upon the current recruitment strategies. The target population for this study consisted of 1,130 prospective freshmen recruited to attend the College of Agriculture in the fall 1997. A comparison of students who resided on the College of Agriculture's 1997 prospective freshmen data base, with the university undergraduate data base gave an accessible population of 226 students. The actual sample size was determined using …

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Rhetoric And Social Struggle: In Search Of The Topoi Of Violence., Edward Christopher Reilly Jan 1998

Rhetoric And Social Struggle: In Search Of The Topoi Of Violence., Edward Christopher Reilly

LSU Historical Dissertations and Theses

The rhetorical study of violence tends to examine violence within larger generic boundaries such as social movements studies or war rhetoric. In order to work toward a generalizable rhetorical theory of violence and discourse, this study examines texts which justify violence across generic boundaries. Accordingly, four case studies individually examine texts which justify political violence. This study compares and contrasts the rhetorical strategies of George Bush, the Unabomber, Earth First! and Abbie Hoffman. This study concludes that there are no universal strategies among the four case studies in the justification of violence. However, there appears to be a continuum of …

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Components That Should Be Included In An Ethics Enhancement Program For State Legislatures., Kenneth Ward Jan 1998

Components That Should Be Included In An Ethics Enhancement Program For State Legislatures., Kenneth Ward

LSU Historical Dissertations and Theses

The purpose of the study was to identify the components and sub-components that should be included in an ethics enhancement program for a state legislature, as perceived by a national panel of experts in the areas of legislative ethics. A Delphi panel comprised of state legislators and state ethics officers was established and comprised of persons representing each of the four regions of the United States. In Round One of the study, the panel identified 12 primary components and 124 related sub-components for an ethics enhancement program in a state legislature. Each of the suggested items were unique and nearly …

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Literacy Stories: Attitudes Toward Literacy And Motivation To Read Among African-American Males In An Urban Community., Donna Parham Washington Jan 1998

Literacy Stories: Attitudes Toward Literacy And Motivation To Read Among African-American Males In An Urban Community., Donna Parham Washington

LSU Historical Dissertations and Theses

Through methods of ethnographic research this study explores the attitudes toward literacy and the motivation to read of African American male secondary school students in an urban community. This study includes historical inquiry obtained through the gathering of oral histories from men who experienced their youth and adolescence in the same geographic area as the secondary school students. Over the past fifty years the neighborhood focused on in this study has undergone tremendous change, both societal and structural. Information obtained through the interviews of the older men and the younger men will be compared to determine changes in literacy attitudes, …

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Parallelization And Implementation Of Approximate Root Isolation For Nonlinear System By Monte Carlo., Ebrahim Khosravi Jan 1998

Parallelization And Implementation Of Approximate Root Isolation For Nonlinear System By Monte Carlo., Ebrahim Khosravi

LSU Historical Dissertations and Theses

This dissertation solves a fundamental problem of isolating the real roots of nonlinear systems of equations by Monte-Carlo that were published by Bush Jones. This algorithm requires only function values and can be applied readily to complicated systems of transcendental functions. The implementation of this sequential algorithm provides scientists with the means to utilize function analysis in mathematics or other fields of science. The algorithm, however, is so computationally intensive that the system is limited to a very small set of variables, and this will make it unfeasible for large systems of equations. Also a computational technique was needed for …

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Sustainable Resources Utilization And Implications For Economic Development In Sub-Saharan Africa: A Case Study Of Cote D'Ivoire., Ahile Nicolas Koudou Jan 1998

Sustainable Resources Utilization And Implications For Economic Development In Sub-Saharan Africa: A Case Study Of Cote D'Ivoire., Ahile Nicolas Koudou

LSU Historical Dissertations and Theses

In the 1960's, sub-Saharan Africa had one of the world's largest rain forests. Today, however, Africa accounts for only 27 percent of the world's forest area. Expansion of agricultural lands at the expense of forests remains the fundamental contributor to deforestation in Cote d'Ivoire. Other factors include a high natural rate of population growth (3.9 percent annually) and flexible immigration policies that create land use pressures. Consequently, Cote d'Ivoire has lost almost 83 percent of its 16 million hectares (39.5 million acres) of tropical forests. Some corrective actions, such as halting illicit harvesting, reforestation and reforming logging activities, have been …

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Passion Plays In The United States: The Contemporary Outdoor Tradition., Charlene Faye Monk Jan 1998

Passion Plays In The United States: The Contemporary Outdoor Tradition., Charlene Faye Monk

LSU Historical Dissertations and Theses

The purpose of this dissertation is to trace the development of the outdoor passion plays in the United States, comparing their content and approach with the continental medieval tradition and analyzing how effectively the current American plays are modifying their presentations to meet the expectations of today's modern society. This study documents the historical development and physical plants for the eight passion play productions in the United States that maintained membership in the Institute of Outdoor Drama and played during the summer seasons of the research period from 1992-1996: The Black Hills Passion Play (1939, Spearfish, South Dakota), The Great …

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Texts And Talk: A Close Look At Gender In Literature Discussion Groups., Peggy Sue Rice Jan 1998

Texts And Talk: A Close Look At Gender In Literature Discussion Groups., Peggy Sue Rice

LSU Historical Dissertations and Theses

This study investigated discourse according to gender-related patterns of eight sixth-grade students (four boys and four girls) as they discussed four realistic fiction short stories in peer-led discussion groups that alternated between same-sex and mixed-sex group compositions. Descriptive data were analyzed according to the constant comparative method of analysis. Quantitative analysis was used to determine discourse patterns in terms of frequency. Data were analyzed to answer the following questions: (1) Will the discourse patterns vary when the students discuss their responses in same-sex groups and mixed-sex groups? If so, in what ways will they vary? (2) Will gender differences be …

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The Selective Digital Integrator: A New Device For Modulated Polarization Spectroscopy., Aljosa Vrancic Jan 1998

The Selective Digital Integrator: A New Device For Modulated Polarization Spectroscopy., Aljosa Vrancic

LSU Historical Dissertations and Theses

A new device, a selective digital integrator (SDI), for the acquisition of modulated polarization spectroscopy (MPS) signals is described. Special attention is given to the accurate measurement of very small (AC component of interest $<$10$\sp{-3}$ x DC component), rapidly modulated ($\sim$50 kHz) signals at or below noise levels. Various data acquisition methods and problems associated with the collection of modulated signals are discussed. The SDI solves most of these problems and has the following advantages: it provides the average-time resolved profile of a modulated signal; it eliminates errors if the modulation is not sinusoidal; it enables separate measurements of the various phases of the signal modulation cycle; it permits simultaneous measurement of absorption, circular dichroism (CD) and linear dichroism (LD) spectra; it facilitates 3-D absorbance measurements; it has a wide gain-switching-free dynamic range (10 orders of magnitude or more); it offers a constant S/N ratio mode of operation; it eliminates the need for photomultiplier voltage feedback, and it has faster scanning speeds. The time-resolution, selectivity, wide dynamic range, and low-overhead on-the-fly data processing are useful for other modulated spectroscopy (MS) and non-MS experiments such as pulse height distribution and time-resolved pulse counting measurements. The advantages of the MPS-SDI method are tested on the first Rydberg electronic transitions of (+)-3-methylcyclopentanone. The experimental results validate the predicted SDI capabilities. However, they also point to two difficulties that had not been noted previously: the presence of LD in a gaseous sample and a pressure-dependence of the relative peak heights of the CD spectrum. Models for these anomalies are proposed. The presence of the oscillatory LD (but not an LD background) is explained with a sample cell model based on the observed polarization-dependent time-resolved profiles of transmitted light intensity. To obtain expressions for these intensities, a theoretical background, which provides a new approach to the treatment of light/matter interaction, is included as an Appendix. To explain the second anomaly, present only at high optical densities, a model based on the presence of scattered light is introduced and verified. The mode of correction for the scattering problem is outlined.

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Managing Promises And Marketing Activities In The Cultivation Of Long-Term Relationship Commitment: The Development Of A Model For The Services Industries., John Michael Weber Jan 1998

Managing Promises And Marketing Activities In The Cultivation Of Long-Term Relationship Commitment: The Development Of A Model For The Services Industries., John Michael Weber

LSU Historical Dissertations and Theses

The concept of promises is important with services, because they can represent some tangible aspect of the service organization upon which the customer can develop expectations and partially evaluate the performance of the organization. It is also important to examine the marketing processes (external, internal, and interactive) the organization utilizes and the consumer can participate in, because these processes act as the communication avenue for the promises. Finally, it is important to evaluate the promises and marketing processes from the perspective of the consumer in order to determine the consumer's expectations, perception of service personnel, evaluations of actual service delivery, …

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Creativity And The Cathartic Moment: Chaos Theory And The Art Of Theatre., Robert E. Brooks Jan 1998

Creativity And The Cathartic Moment: Chaos Theory And The Art Of Theatre., Robert E. Brooks

LSU Historical Dissertations and Theses

This dissertation investigates the potential applications of the scientific paradigm known as "chaos theory" in the examination of dramatic theory. By illuminating the limitations of traditional Newtonian physics and Euclidean geometry, chaos theory conveys philosophical implications that transcend the scientific and provide suitable tools for describing cultural and artistic phenomena. These implications include emphasis on unpredictability, interaction and feedback, qualitative rather that quantitative analyses, and a nonlinear, continuous, even holistic perspective of systems traditionally viewed as dischotomous (such as order and disorder or part and whole). This study examines several standard works of dramatic theory, concentrating on the relationship of …

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Dyslexic College Students: Quest For Literacy., Frances Grace Crochet Jan 1998

Dyslexic College Students: Quest For Literacy., Frances Grace Crochet

LSU Historical Dissertations and Theses

The initial purpose of this study focused on an Orton-Gillingham phonics remediation program and the effect the program had on college students. The emphasis of the study changed due to the fact that the Orton-Gillingham phonics program did not impact the college students' learning, which was mainly due to the students having previously received some form of phonics instruction. The students had learned to compensate for their poor spelling ability through invented spelling, and the use of the computer and the spell checker. The other accommodations that decreased their need for knowledge of a spelling program were the use of …

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Serological And Molecular Biological Studies Of Marine Predator-Prey Systems., Marilyn J. Hoyt Jan 1998

Serological And Molecular Biological Studies Of Marine Predator-Prey Systems., Marilyn J. Hoyt

LSU Historical Dissertations and Theses

Two aspects of species identification were addressed; a molecular approach to identify anchovy larval and serological methods for prey detection in predator gut washes. Analysis of the pattern of restriction fragments of mitochondrial DNA (mtDNA) from adult anchovies from the Gulf of Mexico was employed to speciate four anchovy species. MtDNA isolated from white muscle of adult Anchoa mitchilli, A. hepsetus, A. nasuta and Engraulis eurystole produced an amplified 2.4 Kb DNA product when primers for NADH dehydrogenase 5 and 6 genes were used in polymerase chain reactions (PCR). Digestion of the amplified sequence with Dpn II produced a unique …

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Aflatoxin B(1) And Fumonisin B(1) Co-Contamination: Interactive Effects, Possible Mechanisms Of Toxicity, And Decontamination Procedures., Rebeca Lopez-Garcia Jan 1998

Aflatoxin B(1) And Fumonisin B(1) Co-Contamination: Interactive Effects, Possible Mechanisms Of Toxicity, And Decontamination Procedures., Rebeca Lopez-Garcia

LSU Historical Dissertations and Theses

The current study evaluated interactions between the mycotoxins aflatoxin B$\sb1$ (AFB$\sb1$) and fumonisin B$\sb1$ (FB$\sb1$) in pure systems as well as in corn. During storage at 25$\sp\circ$C with high moisture (ca. 50%), corn contaminated with Aspergillus flavus (L13) and/or Fusarium moniliforme (A00102) presented different aflatoxin and fumonisin levels. Toxin production/degradation varied over storage time (0-45 days). Evaluation of the mutagenicity of unifungal or bifungal corn extracts with the Salmonella/microsomal assay (tester strains TA-100 and TA-98) with metabolic activation (S9) showed positive mutagenic responses. Different ratios of pure AFB$\sb1$/FB$\sb1$ produced divergent mutagenic responses (tester strains TA-100 and TA-98) with S9. The …

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Behavior Of Red Snapper, Lutjanus Campechanus, In Relation To Trawl Modifications To Reduce Shrimp Trawler Bycatch., Donna Reeve Rogers Jan 1998

Behavior Of Red Snapper, Lutjanus Campechanus, In Relation To Trawl Modifications To Reduce Shrimp Trawler Bycatch., Donna Reeve Rogers

LSU Historical Dissertations and Theses

Behavioral responses of young-of-the-year red snapper, Lutjanus campechanus, to alterations in water flow were examined in the laboratory and the field in an effort to facilitate their release from shrimp trawls. Experiments with red snapper, collected by divers, were conducted in a racetrack flume. Four vertical and two horizontal mesh and solid panel types were examined. Four snapper (out of 96) escaped with vertical panels and thirteen fish (out of 48) exited with horizontal panels. Escapes occurred primarily with solid panels containing 0.95-cm holes drilled at 5-cm intervals. However, snapper that escaped with solid horizontal panels frequently went back into …

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Development And Assessment Of A Property Rights-Based Measure Of State Regulatory Climate., Ferdinand Francis Wirth Iii Jan 1998

Development And Assessment Of A Property Rights-Based Measure Of State Regulatory Climate., Ferdinand Francis Wirth Iii

LSU Historical Dissertations and Theses

States implement many of the environmental laws enacted during the last thirty years. A key policy issue is the effect of differences in state institutions and environmental policies on the location of livestock agriculture. There is widespread belief that the stringency of state environmental regulations, known as regulatory climate, is an important factor influencing the location, growth and expansion decisions of livestock agriculture. Existing regulatory climate measures are not tailored to agriculture, and their use has given mixed results. Conceptual and empirical models were developed for the U.S. aquaculture industry, based on elements of public choice and firm location theories …

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Wavelet-Based Registration Of Medical Images., Raj Sharman Jan 1998

Wavelet-Based Registration Of Medical Images., Raj Sharman

LSU Historical Dissertations and Theses

Registration is the process of spatially aligning two objects and is normally a preprocessing step in most object recognition algorithms. Registration of images and recognition of signatures of objects in images is important for clinical and diagnostic purposes in medicine. Recognizing structure, potential targets for defense purposes and changes in the terrain, from aerial surveillance images and SAR images is the focus of extensive research and development today. Automatic Target Recognition is becoming increasingly important as the defense systems and armament technology move to use smarter munitions. Registration of images is a preprocessing step in any kind of machine vision …

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Arthur Miller In Montreal: Cultural Transfer Of American Plays In Quebec (1965-1997)., Bernard Lavoie Jan 1998

Arthur Miller In Montreal: Cultural Transfer Of American Plays In Quebec (1965-1997)., Bernard Lavoie

LSU Historical Dissertations and Theses

In the 1960s, American plays presented in Montreal were translated in France; the following decade saw the first of American plays translated or adapted in Quebec. In the 1980s, the translative practices employed in the seventies proved the dominant mode. In the 1990s, only exceptionally has an American play been presented in a translation originating outside of Quebec. It is now the rule that all foreign plays produced in Quebec are translated in the Quebecois idiom. This translative situation has stabilized, and the translation of American plays into Quebecois reflects an established practice. The tracing and analysis of this translative …

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United States Foreign Policy And Media Coverage Of Uzbekistan: A Case Study., Mardon Nigmatovich Yakubov Jan 1998

United States Foreign Policy And Media Coverage Of Uzbekistan: A Case Study., Mardon Nigmatovich Yakubov

LSU Historical Dissertations and Theses

This study reviews the impact of U.S. political interests on media coverage of Uzbekistan, a Central Asian republic which became independent after the breakup of the Soviet Union. A content analysis of coverage from 1991 to 1996 in the New York Times, Washington Post, and Los Angeles Times was compared to American government documents and pronouncements on Uzbekistan. Striking similarities between U.S. policy towards Uzbekistan and the negative interpretation of events appearing in American newspapers were found. The democracy and human rights agendas advanced by U.S. officials apparently prompted editors and reporters to focus more on these subjects, while overlooking …

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Aspects Of Searching And Tunneling Behavior In Resource Utilization By The Formosan Subterranean Termite, Coptotermes Formosanus Shiraki., Justin Carl Hedlund Jan 1998

Aspects Of Searching And Tunneling Behavior In Resource Utilization By The Formosan Subterranean Termite, Coptotermes Formosanus Shiraki., Justin Carl Hedlund

LSU Historical Dissertations and Theses

Formosan subterranean termites, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae), were acclimated with different masses of pine or no wood (control) and then allowed access to a thin sand filled tunneling chamber. As available pine increased, termite survival and food consumption increased but search tunnel volume decreased. Increased food size resulted in termites excavating fewer exploratory tunnels due to decreases in secondary and tertiary branch tunnels. An increase in food size also decreased the total length of a search tunnel network, due to decreases in primary and secondary branch order lengths. Search tunnel networks had proportionally more length devoted to primary tunnels …

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Discovery Of A Supernova Explosion At Half The Age Of The Universe, S. Perlmutter, G. Aldering, M. Della Valle, S. Deustua, R. S. Ellis, S. Fabbro, A. Fruchter, G. Goldhaber, D. E. Groom, I. M. Hook, A. G. Kim, M. Y. Kim, R. A. Knop, C. Lidman, R. G. Mcmahon, P. Nugent, R. Pain, N. Panagia, C. R. Pennypacker, P. Ruiz-Lapuente, B. Schaefer, N. Walton Jan 1998

Discovery Of A Supernova Explosion At Half The Age Of The Universe, S. Perlmutter, G. Aldering, M. Della Valle, S. Deustua, R. S. Ellis, S. Fabbro, A. Fruchter, G. Goldhaber, D. E. Groom, I. M. Hook, A. G. Kim, M. Y. Kim, R. A. Knop, C. Lidman, R. G. Mcmahon, P. Nugent, R. Pain, N. Panagia, C. R. Pennypacker, P. Ruiz-Lapuente, B. Schaefer, N. Walton

Faculty Publications

The ultimate fate of the Universe, infinite expansion or a big crunch, can be determined by using the redshifts and distances of very distant supernovae to monitor changes in the expansion rate. We can now find large numbers of these distant supernovae, and measure their redshifts and apparent brightnesses; moreover, recent studies of nearby type Ia supernovae have shown how to determine their intrinsic luminosities- and therefore with their apparent brightnesses obtain their distances. The >50 distant supernovae discovered so far provide a record of changes in the expansion rate over the past several billion years. However, it is necessary …

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Egret Observations Of The Extragalactic Gamma-Ray Emission, P. Sreekumar, D. L. Bertsch, B. L. Dingus, J. A. Esposito, C. E. Fichtel, R. C. Hartman, S. D. Hunter, G. Kanbach, D. A. Kniffen, Y. C. Lin, H. A. Mayer-Hasselwander, P. F. Michelson, C. Von Montigny, A. Mücke, R. Mukherjee, P. L. Nolan, M. Pohl, O. Reimer, E. Schneid, J. G. Stacy, F. W. Stecker, D. J. Thompson, T. D. Willis Jan 1998

Egret Observations Of The Extragalactic Gamma-Ray Emission, P. Sreekumar, D. L. Bertsch, B. L. Dingus, J. A. Esposito, C. E. Fichtel, R. C. Hartman, S. D. Hunter, G. Kanbach, D. A. Kniffen, Y. C. Lin, H. A. Mayer-Hasselwander, P. F. Michelson, C. Von Montigny, A. Mücke, R. Mukherjee, P. L. Nolan, M. Pohl, O. Reimer, E. Schneid, J. G. Stacy, F. W. Stecker, D. J. Thompson, T. D. Willis

Faculty Publications

The all-sky survey in high-energy gamma rays (E > 30 MeV) carried out by EGRET aboard the Compton Gamma Ray Observatory provides a unique opportunity to examine in detail the diffuse gamma-ray emission. The observed diffuse emission has a Galactic component arising from cosmic-ray interactions with the local interstellar gas and radiation, as well as an almost uniformly distributed component that is generally believed to originate outside the Galaxy. Through a careful study and removal of the Galactic diffuse emission, the flux, spectrum, and uniformity of the extragalactic emission are deduced. The analysis indicates that the extragalactic emission is well described …

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Starburst-Like Dust Extinction In The Small Magellanic Cloud, Karl D. Gordon, Geoffrey C. Clayton Jan 1998

Starburst-Like Dust Extinction In The Small Magellanic Cloud, Karl D. Gordon, Geoffrey C. Clayton

Faculty Publications

The recent discovery that the ultraviolet (UV) dust extinction in starburst galaxies is similar to that found in the Small Magellanic Cloud (SMC) motivated us to reinvestigate the UV extinction found in the SMC. We have been able to improve significantly on previous studies by carefully choosing pairs of well-matched reddened and unreddened stars. In addition, we benefited from the improved signal-tonoise ratio of the NEWSIPS International Ultraviolet Explorer (WE) data and the larger sample of SMC stars now available. Searching the WE Final Archive, we found only four suitable early-type stars that were significantly reddened and had well-matched comparison …

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