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Understanding The Biological Concept "Bird": A Kindergarten Case Study., Dilek Buchholz Jan 2000

Understanding The Biological Concept "Bird": A Kindergarten Case Study., Dilek Buchholz

LSU Historical Dissertations and Theses

The purpose of this qualitative, multiple case study of 14 students in a metropolitan public school in the Deep South was to find out, during a period of three months, what these kindergarten-aged children knew about birds, whether this knowledge represented current scientific thought, if such science instruction meaningfully affected their prior knowledge, and if so, what the factors during instruction that seemed to influence their understanding of the concept of bird were. The research was conducted in three phases; preinstruction interviews, instruction, and postinstruction interviews. The theoretical framework for this research was based on the Human Constructivism theory of …

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Development Of Novel Separation Strategies: Part I. The Separation And Characterization Of The Insecticidal Pyrethrin Esters. Part Ii. Separations In Capillary Electrochromatography., Charles William Henry Iii Jan 2000

Development Of Novel Separation Strategies: Part I. The Separation And Characterization Of The Insecticidal Pyrethrin Esters. Part Ii. Separations In Capillary Electrochromatography., Charles William Henry Iii

LSU Historical Dissertations and Theses

The analytical investigation of the natural insecticide pyrethrum has been conducted. In this research, novel approaches were designed to yield either faster, or more complete separation of the active pesticidal esters in pyrethrum extracts as well as more complete conformational information of the structures of these compounds in solution. A combination of techniques was used: micellar electrokinetic chromatography (MEKC), nuclear magnetic resonance spectroscopy (NMR), and capillary electrochromatography (CEC). Using MEKC, an optimized separation of the six pyrethrin esters was achieved in 25 minutes with 25 mM Tris, buffered at pH 9, containing 30 mM SDS, 25% (v/v) acetonitrile, and an …

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Evaluating Alternative Instructional Strategies To Improve Sixth Graders' Reading Comprehension., Emma Mccall Schorzman Jan 2000

Evaluating Alternative Instructional Strategies To Improve Sixth Graders' Reading Comprehension., Emma Mccall Schorzman

LSU Historical Dissertations and Theses

Although little empirical evidence supporting various instructional strategies for teaching reading comprehension exists, many educators utilize particular strategies assuming their effectiveness. Because difficulties with comprehension are intensified as students reach the intermediate grades, it is necessary that middle school educators instruct using strategies empirically supported through research. This mixed-method study examined the effectiveness of the Directed Reading-Thinking Activity (Stauffer, 1969), the PreP technique (Langer, 1981), and graphic organizers (Barron, 1969), three popular strategies among middle school teachers. Six teachers participated in the two-group design, pretest/posttest study; over a seven-week period, three of the teachers instructed their sixth-grade students using lessons …

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An Information Theoretic Approach To Content Based Image Retrieval., John Morris Zachary Jr Jan 2000

An Information Theoretic Approach To Content Based Image Retrieval., John Morris Zachary Jr

LSU Historical Dissertations and Theses

We propose an information theoretic approach to the representation and comparison of color features in digital images to handle various problems in the area of content-based image retrieval. The interpretation of color histograms as joint probability density functions enables the use of a wide range of concepts from information theory to be considered in the extraction of color features from images and the computation of similarity between pairs of images. The entropy of an image is a measure of the randomness of the color distribution in an image. Rather than replacing color histograms as an image representation, we demonstrate that …

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Well Integrity Mechanism, Failure, And Testing In Shallow Marine Sediments., Desheng Zhou Jan 2000

Well Integrity Mechanism, Failure, And Testing In Shallow Marine Sediments., Desheng Zhou

LSU Historical Dissertations and Theses

The leak-off test (LOT) is an in-situ method for testing casing shoe integrity in a well. It is used to evaluate the cement and formation integrity relative to the well plan specifications. The results determine whether any remedial cementing or corrective actions are required and are a basis for planning future wells in the area. Typical analysis of LOTs assumes an elastic wellbore and involves identification of linear trends on the recorded plots. However, LOTs recorded in shallow marine sediments (SMS) are inherently nonlinear and their analysis is a problem. Starting from the analyses of shallow soil properties, LOT plots, …

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Salinity History Of Coastal Marshes Reconstructed From Diatom Remains, Michael L. Parsons, Quay Dortch, R. Eugene Turner, Nancy N. Rabalais Dec 1999

Salinity History Of Coastal Marshes Reconstructed From Diatom Remains, Michael L. Parsons, Quay Dortch, R. Eugene Turner, Nancy N. Rabalais

Faculty Publications

Sediment cores were collected from three Louisiana coastal marsh ponds, dated with radioisotopes, and analyzed for diatom remains to determine if long-term salinity changes were evident in the sediment record. A diatom-based salinity index formulated from a statistical comparison of available salinity data and changing diatom assemblages demonstrated that diatom remains appear to preserve salinity signals in coastal brackish and salt marsh environments. The salinity index was applied to sediment cores spanning the late 1600s to the 1990s and provided a more complete record of salinity than field data, which were temporally and spatially incomplete. The salinity reconstructions indicated that …

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Maximizing Economic Returns From Sugarcane Production Through Optimization Of Harvest Schedule (Bulletin #868), Michael E. Salassi, Lonnie P. Champagne, Benjamin L. Legendre Dec 1999

Maximizing Economic Returns From Sugarcane Production Through Optimization Of Harvest Schedule (Bulletin #868), Michael E. Salassi, Lonnie P. Champagne, Benjamin L. Legendre

LSU AgCenter Bulletins

This bulletin presents a methodology for the incorporation of within-season sucrose accumulation in sugarcane into an optimal single-season, daily harvest scheduling model at the individual farm level.

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A Class Of Non-Binary Matroids With Many Binary Minors, Allan D. Mills, James G. Oxley Sep 1999

A Class Of Non-Binary Matroids With Many Binary Minors, Allan D. Mills, James G. Oxley

Faculty Publications

It is a well-known result of Tutte, A homotopy theorem for matroids, I, II, Trans. Amer. Math. Soc. 88 (1958) 144-174. that U2,4 is the only non-binary matroid M such that, for every element e, both M\e and M/e are binary. Oxley generalized this result by characterizing the non-binary matroids M such that, for every element e of M, the deletion M\e or the contraction M/e is binary. We characterize those non-binary matroids M such that, for all elements e and f, at least two of M\e, f; M\e/f; M/e\f; and M/e, f are binary. © 1999 Elsevier Science B.V. …

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The Impact Of Accelerating Land-Use Change On The N-Cycle Of Tropical Aquatic Ecosystems: Current Conditions And Projected Changes, J. A. Downing, M. Mcclain, R. Twilley, J. M. Melack, J. Elser, Nancy N. Rabalais, W. M. Lewis Jr., R. Eugene Turner, J. Corredor, D. Soto, A. Yanez Arancibia, J. A. Kopaska, R. W. Howarth Jul 1999

The Impact Of Accelerating Land-Use Change On The N-Cycle Of Tropical Aquatic Ecosystems: Current Conditions And Projected Changes, J. A. Downing, M. Mcclain, R. Twilley, J. M. Melack, J. Elser, Nancy N. Rabalais, W. M. Lewis Jr., R. Eugene Turner, J. Corredor, D. Soto, A. Yanez Arancibia, J. A. Kopaska, R. W. Howarth

Faculty Publications

Published data and analyses from temperate and tropical aquatic systems are used to summarize knowledge about the potential impact of land-use alteration on the nitrogen biogeochemistry of tropical aquatic ecosystems, identify important patterns and recommend key needs for research. The tropical N-cycle is traced from pre-disturbance conditions through the phases of disturbance, highlighting major differences between tropical and temperate systems that might influence development strategies in the tropics. Analyses suggest that tropical freshwaters are more frequently N-limited than temperate zones, while tropical marine systems may show more frequent P limitation. These analyses indicate that disturbances to pristine tropical lands will …

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A Confederate Dame: Cornelia Jones Pond's Reminiscence Captures A Vanished Grandeur, Karen Rae Mehaffey Jun 1999

A Confederate Dame: Cornelia Jones Pond's Reminiscence Captures A Vanished Grandeur, Karen Rae Mehaffey

Civil War Book Review

In the recent past, an excellent variety of biographies, diaries, and memoirs have been published about women during the Civil War period. Among those have been accounts of nurses, spies, and extraordinary women. Others recount the lives of ordinary women living in extraordinary times. In the latter....

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Characterization Of Hypoxia: Topic 1 Report For The Integrated Assessment On Hypoxia In The Gulf Of Mexico, Nancy N. Rabalais, R. Eugene Turner, Dubravko Justic, Quay Dortch, William J. Wiseman May 1999

Characterization Of Hypoxia: Topic 1 Report For The Integrated Assessment On Hypoxia In The Gulf Of Mexico, Nancy N. Rabalais, R. Eugene Turner, Dubravko Justic, Quay Dortch, William J. Wiseman

Faculty Publications

No abstract provided.

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A Reanalysis Of The Ultraviolet Extinction From Interstellar Dust In The Large Magellanic Cloud, K. A. Misselt, Geoffrey C. Clayton, Karl D. Gordon Apr 1999

A Reanalysis Of The Ultraviolet Extinction From Interstellar Dust In The Large Magellanic Cloud, K. A. Misselt, Geoffrey C. Clayton, Karl D. Gordon

Faculty Publications

We have reanalyzed the Large Magellanic Cloud's (LMC) ultraviolet (UV) extinction using data from the IUE final archive. Our new analysis takes advantage of the improved signal-to-noise ratio of the IUE NEWSIPS reduction, the exclusion of stars with very low reddening, the careful selection of well-matched comparison stars, and an analysis of the effects of Galactic foreground dust. Differences between the average extinction curves of the 30 Dor region and the rest of the LMC are reduced compared with previous studies. We find that there is a group of stars with very weak 2175 Å bumps that lie in or …

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Nutrient Enhanced Coastal Ocean Productivity In The Northern Gulf Of Mexico, William J. Wiseman Jr., Michael J. Dagg, Nancy N. Rabalais, Terry E. Whitledge Apr 1999

Nutrient Enhanced Coastal Ocean Productivity In The Northern Gulf Of Mexico, William J. Wiseman Jr., Michael J. Dagg, Nancy N. Rabalais, Terry E. Whitledge

Faculty Publications

No abstract provided.

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Synthesis Of A Novel ??-Amino Acid Capable Of Stabilizing A 310-Helix Via Side-Chain Salt-Bridging, Reema K. Thalji Apr 1999

Synthesis Of A Novel ??-Amino Acid Capable Of Stabilizing A 310-Helix Via Side-Chain Salt-Bridging, Reema K. Thalji

Honors Capstones

No abstract provided.

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Pressure Dependence Of The Metal-Insulator Transition In Fesi1-Xa1x, Brian Perone Apr 1999

Pressure Dependence Of The Metal-Insulator Transition In Fesi1-Xa1x, Brian Perone

Honors Capstones

No abstract provided.

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Novel Precursors For Chemical Vapor Deposition Of Copper Metal, Zuzanna T. Cygan Apr 1999

Novel Precursors For Chemical Vapor Deposition Of Copper Metal, Zuzanna T. Cygan

Honors Capstones

No abstract provided.

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Diet Overlap Of Native And Translocated Northern White-Tailed Deer In Southeastern Louisiana, Brian Matthew Zielinski Mar 1999

Diet Overlap Of Native And Translocated Northern White-Tailed Deer In Southeastern Louisiana, Brian Matthew Zielinski

LSU Historical Dissertations and Theses

I used microhistological analysis of fecal pellets to estimate and compare seasonal diet compositions between free-ranging, southern and translocated. northern woodland white-tailed deer (Odocoileus virginianus) on Golden Ranch Hunting Farm, Gheens, Louisiana,. over four consecutive seasons, from January 1997 through January 1998. I analyzed pellet groups with Near Infrared Reflectance Spectroscopy (NIRS) and wet chemistry techniques to evaluate and compare crude protein levels between populations of deer and provide indices of diet quality. On average, native and translocated deer diets were 87.65% similar during the entire study, and were significantly associated during all seasons ( P < 0.0000 I ). suggesting that deer fed on similar plant species in like quantities throughout the year. Few differences were found in plant selection frequencies per fecal sample. hut significant differences were detected (P 0.00 l) among deer populations in the use of Berchemia scandens and Vitis rotundifolia during spring. Northern deer also ingested a greater diversity of plants (P < 0.05) during spring and winter; and fecal crude protein levels were similar (P > 0.05) in all seasons …

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Erratum: Lizards Took Express Train To Polynesia (Nature (1999) 397 (13- 114), C. Austin Feb 1999

Erratum: Lizards Took Express Train To Polynesia (Nature (1999) 397 (13- 114), C. Austin

Faculty Publications

No abstract provided.

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Integral Kernel Operators In The Cochran -Kuo -Sengupta Space., John Joseph Whitaker Jan 1999

Integral Kernel Operators In The Cochran -Kuo -Sengupta Space., John Joseph Whitaker

LSU Historical Dissertations and Theses

This dissertation contains several results about integral kernel operators in white noise analysis. The results found here apply to the space of test functions and generalized functions that were constructed in the paper of Cochran, Kuo, and Sengupta, based on a sequence of numbers &cubl0;an&cubr0; infinityn=0. . We shall prove results about existence, restrictions, and extensions of integral kernel operators based on the conditions on &cubl0;an&cubr0; infinityn=0. contained in the paper of Kubo, Kuo, and Sengupta. Also, we shall prove an analytic property and growth condition of the symbol of a continuous operator in CKS space. Our results are similar …

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Estimating The Returns To Investment In Louisiana's Agricultural Research System., Yongli Zhu Jan 1999

Estimating The Returns To Investment In Louisiana's Agricultural Research System., Yongli Zhu

LSU Historical Dissertations and Theses

This study demonstrates one way in which the combined nonparametric and parametric estimates of returns-to-research can be used to build a stronger argument for public investment in agricultural research. The data used in this study were constructed from time series information covering the period 1949--95. Tornqvist-Theil quantity indices were calculated to determine the implicit state price for each input category. The returns-to-research in Louisiana agriculture were estimated using both nonparametric and parametric estimators, with appropriate emphasis given to lag structures, data coherence, and functional forms. Model misspecification testing for the parametric model was examined. Internal rates of return were calculated …

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On The Numerical Solution Of The Cylindrical Poisson Equation For Isolated Self -Gravitating Systems., Howard Saul Cohl Jan 1999

On The Numerical Solution Of The Cylindrical Poisson Equation For Isolated Self -Gravitating Systems., Howard Saul Cohl

LSU Historical Dissertations and Theses

This dissertation addresses the need for an accurate and efficient technique which solves the Poisson equation for arbitrarily complex, isolated, self-gravitating fluid systems. Generally speaking, a potential solver is composed of two distinct pieces: a boundary solver and an interior solver. The boundary solver computes the potential, phi(xB) on a surface which bounds some finite volume of space, V, and contains an isolated mass-density distribution, rho(x). Given rho(x) and phi(xB), the interior solver computes the potential phi(x) everywhere within V. Herein, we describe the development of a numerical technique which efficiently solves Poisson's equation in cylindrical coordinates on massively parallel …

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Clarinet Concertos By Post World War Ii Generation Norwegian Composers: Bjorn Kruse, Olav Berg, And Rolf Wallin., Beverly Ann Gibson Jan 1999

Clarinet Concertos By Post World War Ii Generation Norwegian Composers: Bjorn Kruse, Olav Berg, And Rolf Wallin., Beverly Ann Gibson

LSU Historical Dissertations and Theses

A substantial body of Norwegian clarinet literature exists that is infrequently performed outside of the Scandinavian countries and Europe. A new generation of composers emerged in the 1980s who have made visible their own individual approaches to composition. This monograph focuses on a selection of clarinet concertos composed by Bjorn Kruse (b. 1946), Olav Berg (b. 1949), and Rolf Wallin (b. 1957) which represent the most extensive pieces for clarinet in the respective composers' outputs to date and have been awarded prizes in composition contests. The composers have distinguished themselves as leading figures in the contemporary music scene in Norway, …

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Pine-Polyethylene (Wood -Polymer) Composites: Synthesis And Mechanical Behavior Characterization., Parviz S. Razi Jan 1999

Pine-Polyethylene (Wood -Polymer) Composites: Synthesis And Mechanical Behavior Characterization., Parviz S. Razi

LSU Historical Dissertations and Theses

Processing of recycled wood chips, recently produced after extraction of creosote from telephone posts and railroad crossties, and combining them with a recycled polymer for the synthesis of novel composite materials would initiate a new trend toward preservation of natural resources. The challenge is taken in this work to produce and study the properties of such materials for further advancement of science. In the present study, addition of pine wood chips to HDPE reduced the tensile strength and break strain in tensile loading. Smaller wood chips generally resulted in smaller reductions. Peak load, modulus of rupture and stiffness were slightly …

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Design Of Work-Rest Schedules For Vdt Operators., Rana Balci Jan 1999

Design Of Work-Rest Schedules For Vdt Operators., Rana Balci

LSU Historical Dissertations and Theses

The number of musculoskeletal and psychological discomforts is increasing as a result of continuing growth of VDT work. Although ergonomic improvements in workstation design can be applied, an effective work-rest schedule is an economical way to reduce these problems. The objective of this research was to determine an effective work-rest schedule for VDT operators. In addition to a discomfort questionnaire, performance and electromyography measurements from trapezius and flexor carpi radialis were used. Three different work-rest schedules were applied: 60-minute work/10-minute rest, 30-minute work/5-minute rest, and for the third schedule, the subjects received four breaks from VDT work each hour additional …

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How Does Undergraduate College Biology Students' Level Of Understanding, In Regard To The Role Of The Seed Plant Root System, Relate To Their Level Of Understanding Of Photosynthesis?, James Gicheha Njeng'ere Jan 1999

How Does Undergraduate College Biology Students' Level Of Understanding, In Regard To The Role Of The Seed Plant Root System, Relate To Their Level Of Understanding Of Photosynthesis?, James Gicheha Njeng'ere

LSU Historical Dissertations and Theses

This research study investigated how undergraduate college biology students' level of understanding of the role of the seed plant root system relates to their level of understanding of photosynthesis. This research was conducted with 65 undergraduate non-majors biology who had completed 1 year of biology at Louisiana State University in Baton Rouge and Southeastern Louisiana University in Hammond. A root probe instrument was developed from some scientifically acceptable propositional statements about the root system, the process of photosynthesis, as well as the holistic nature of the tree. These were derived from research reviews of the science education and the arboriculture …

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Improving Searches For Gravitational Wave Bursts., Carroll Andrew Morse Jan 1999

Improving Searches For Gravitational Wave Bursts., Carroll Andrew Morse

LSU Historical Dissertations and Theses

The first half of this dissertation discusses the details of calibrating a resonant mass gravitational wave antenna and determining its sensitivity. We dispense with the assumption of a perfectly tuned antenna and transducer and model the system using a coordinate rotation. We demonstrate that all of the important model parameters can be directly measured. We demonstrate that the signal response of the two detector modes should be equal despite any mistuning and that the mistuning parameter can be measured in two separate ways. These properties are useful for determining the degree to which a real detector's behavior parallels that of …

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An Analysis And Performer's Guide To The Sonatine For Flute And Piano By Pierre Boulez., Diana M. Tiffany Jan 1999

An Analysis And Performer's Guide To The Sonatine For Flute And Piano By Pierre Boulez., Diana M. Tiffany

LSU Historical Dissertations and Theses

In spite of the preeminence of its composer, the Sonatine for Flute and Piano by Pierre Boulez is not a well known work. The piece poses truly formidable technical and aesthetic challenges for players and audiences. The purpose of this study is to present an analysis and some practical suggestions for flutists preparing the piece for performance. This serial-based work is divided into four continuous main stanzas, each demonstrating a different style and varying compositional techniques while using the same row. The repetition of specific pitch-class sets, rhythm motives, and pitch classes within each stanza lends each one aurally identifiable …

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An Empirical Examination Of Maximum Entropy Estimation., Randall Charles Campbell Jan 1999

An Empirical Examination Of Maximum Entropy Estimation., Randall Charles Campbell

LSU Historical Dissertations and Theses

Maximum entropy estimation is a relatively new estimation technique in econometrics. We carry out several Monte Carlo experiments using real data as a basis in order to understand the properties of the maximum entropy estimator. We compare the maximum entropy and generalized maximum entropy estimators to traditional estimation techniques in linear regression, binary choice, and multinomial choice models. In addition, we discuss maximum entropy estimation in censored and truncated regression models. We find that the generalized maximum entropy estimator dominates the logit estimator and the multinomial logit estimator in Monte Carlo experiments. The generalized maximum entropy estimator in discrete choice …

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Development Of Immunochemical Methods For Gossypol Analysis., Xi Wang Jan 1999

Development Of Immunochemical Methods For Gossypol Analysis., Xi Wang

LSU Historical Dissertations and Theses

Gossypol is a reactive polyphenolic compound present in the cotton plant. During cottonseed processing, gossypol can react with other compounds to form bound gossypol. Gossypol analyses using chemical methods do not always agree with its bioavailability to animal possibly because of various bound forms of gossypol with different stabilities in vivo and the (+/-)-gossypol enantiomers with different biological activities. The objectives of this research were to produce anti-gossypol antibodies and use antibodies to study gossypol chemistry and to analyze gossypol in cottonseed samples and cottonseed by-products. Polyclonal antibodies were produced from rabbits after they were immunized with gossypol-LPH (Limulus polyphemus …

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Rhetorical Theory: Discourse Practices Of Utopian Communities., Irvin Andreu Wilhite Jan 1999

Rhetorical Theory: Discourse Practices Of Utopian Communities., Irvin Andreu Wilhite

LSU Historical Dissertations and Theses

This study is interested in idealized expressions of political ideology in utopian science fiction literature written during the Cold War following World War II. Accordingly, a dramatistic analysis is presented regarding fourteen science fiction novels published between 1949 and 1959 which describes their thematic content with respect to consonant and contrasting moral/social/political positions and the influx of advancing technology. A description of the canonical works precedes this analysis. Subsequently, contemporary related studies are lightly analyzed for comparative and contextual considerations. Conclusions address the importance of rhetoric and performance in restoring the destabilized balance of power as an aftermath of violent …

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