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Effects Of Rotational Grazing On Rodents And Raptors In A Coastal Grassland, Matthew D. Johnson, Christa M. Horn Dec 2008

Effects Of Rotational Grazing On Rodents And Raptors In A Coastal Grassland, Matthew D. Johnson, Christa M. Horn

Western North American Naturalist

We conducted a 4-year experiment to assess the impacts of rotational cattle grazing on rodents and raptors in a mesic coastal grassland in northwestern California. Live-trapping indicated that rodent abundance declined by 69% on the grazed area and increased by 14% on the ungrazed area. Raptor use of the grazed area declined by 15% and increased on the ungrazed area by 63%. Measures of giving-up density indicated that rodents perceived a 25% higher predation risk on grazed area than on ungrazed area, but raptor hunting surveys indicated that risk of depredation from raptors was 2.5 times lower in the grazed …

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Distribution And Status Of The Yellow-Faced Pocket Gopher In Kansas, Justin D. Hoffman, Jerry R. Choate Dec 2008

Distribution And Status Of The Yellow-Faced Pocket Gopher In Kansas, Justin D. Hoffman, Jerry R. Choate

Western North American Naturalist

Previous research suggests that the yellow-faced pocket gopher (Cratogeomys castanops) occupies a restricted range in western Kansas that is surrounded by the range of the plains pocket gopher (Geomys bursarius), which is regarded as a superior competitor. To determine whether the plains pocket gopher has encroached on the range of the yellow-faced pocket gopher in the past 35 years and to better understand the geographic relationships of these species, we trapped pocket gophers in western Kansas and collected soil texture and land cover data. We used ArcView 3.2 to map the distributions of these species in …

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Sex Ratios Of The White-Tailed Antelope Ground Squirrel (Ammospermophilus Leucurus), Indian Wells Valley, San Bernardino County, California, Charles J. Randel Iii, Howard O. Clark Jr. Dec 2008

Sex Ratios Of The White-Tailed Antelope Ground Squirrel (Ammospermophilus Leucurus), Indian Wells Valley, San Bernardino County, California, Charles J. Randel Iii, Howard O. Clark Jr.

Western North American Naturalist

We studied the white-tailed antelope ground squirrel during spring and summer 2006 to determine young-of-the-year and adult sex ratios in the Indian Wells Valley, San Bernardino County, California. We calculated a young-of-the-year sex ratio of 1.45:1 (female to male), whereas the adult sex ratio was approximately 1:1. Our young-of-the-year sex ratio was greater than the 1.1:1 (female to male) natal sex ratio previously reported. Differences between young-of-the-year and adult sex ratios may represent low female young-of-the-year survivorship in the Indian Wells Valley.

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The Biological Soil Crusts Of The San Nicolas Island: Enigmatic Algae From A Geographically Isolated Ecosystem, Valerie R. Flechtner, Jeffrey R. Johansen, Jayne Belnap Dec 2008

The Biological Soil Crusts Of The San Nicolas Island: Enigmatic Algae From A Geographically Isolated Ecosystem, Valerie R. Flechtner, Jeffrey R. Johansen, Jayne Belnap

Western North American Naturalist

Composite soil samples from 7 sites on San Nicolas Island were evaluated quantitatively and qualitatively for the presence of cyanobacteria and eukaryotic microalgae. Combined data demonstrated a rich algal flora with 19 cyanobacterial and 19 eukaryotic microalgal genera being identified, for a total of 56 species. Nine new species were identified and described among the cyanobacteria and the eukaryotic microalgae that were isolated: Leibleinia edaphica, Aphanothece maritima, Chroococcidiopsis edaphica, Cyanosarcina atroveneta, Hassallia californica, Hassallia pseudoramosissima, Microchaete terrestre, Palmellopsis californicus, and Pseudotetracystis compactis. Distinct distributional patterns of algal taxa existed among sites on the island and among soil algal floras of …

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Water Stress And Hybridization Between Quercus Gambelii And Quercus Grisea, Nathan G. Swenson, Jeanne M. Fair, Jeff Heikoop Dec 2008

Water Stress And Hybridization Between Quercus Gambelii And Quercus Grisea, Nathan G. Swenson, Jeanne M. Fair, Jeff Heikoop

Western North American Naturalist

The historical and environmental forces involved in determining the geographic location of plant hybrid zones have long been of interest. Often hybrid zones appear to be intimately tied to the environment, yet because many abiotic factors covary it is often difficult to understand which are truly the most important in maintaining the position and structure of a hybrid zone. This study uses empirical data and modeling analyses to examine whether abiotic factors are responsible for the location and structure of an oak (Quercus) hybrid zone and, if so, which factors are the most important. Specifically, leaf trait measurements …

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Unnatural Landscapes: Tracking Invasive Species By Ceiridwen Terrill, Howard O. Clark Jr. Dec 2008

Unnatural Landscapes: Tracking Invasive Species By Ceiridwen Terrill, Howard O. Clark Jr.

Western North American Naturalist

No abstract provided.

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New Distributional Records Of The Red Squirrel (Tamiasciurus Hudsonicus) In Western New Mexico And Evidence For Its Extirpation From The Zuni Mountains, Jennifer K. Frey Dec 2008

New Distributional Records Of The Red Squirrel (Tamiasciurus Hudsonicus) In Western New Mexico And Evidence For Its Extirpation From The Zuni Mountains, Jennifer K. Frey

Western North American Naturalist

In the American Southwest, the red squirrel (Tamiasciurus hudsonicus) occurs as disjunct populations in coniferous forests on mountaintops. There is a paucity of information concerning the species' distribution and habitat in western New Mexico. I report new records that document and verify the occurrence of red squirrels in additional montane areas in west central New Mexico, including the Mangas Mountains, Canovas Rim, Turner Mountain, Tularosa Mountains, Elk Mountains, Bearwallow Mountain, and Pinos Altos Mountains. I also report observations of red squirrels from an atypical habitat—low-elevation riparian forests. These new records suggest that the geographic distribution of the species …

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Optimal Temperatures For Growth And Upper Thermal Tolerance Of Juvenile Northern Leatherside Chub, Eric J. Billman, Eric J. Wagner, Ronney E. Arndt, Erin Vandyke Dec 2008

Optimal Temperatures For Growth And Upper Thermal Tolerance Of Juvenile Northern Leatherside Chub, Eric J. Billman, Eric J. Wagner, Ronney E. Arndt, Erin Vandyke

Western North American Naturalist

We examined optimal temperatures for growth and the upper thermal tolerance of juvenile northern leatherside chub (Lepidomeda copei). We conducted 2 experiments using the acclimated chronic-exposure method to estimate optimal temperature for growth of age-0 northern leatherside chub (range 12.8–28.3 °C). Upper thermal tolerance was estimated using the critical thermal maximum (CTM) and upper incipient lethal temperature (UILT) methods for fish acclimated at 15, 18, 23, and 28 °C. We also measured stream temperatures in Yellow Creek, Summit County, Utah, during July–August 2006 to compare our results to actual summer stream temperatures. Survival in growth tests was not …

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End Matter, Vol. 68 No. 4 Dec 2008

End Matter, Vol. 68 No. 4

Western North American Naturalist

No abstract provided.

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Short-Term Effects Of Wildfire On Montane Stream Ecosystems In The Southern Rocky Mountains: One And Two Years Post-Burn, Sharon J. Hall, Danica Lombardozzi Dec 2008

Short-Term Effects Of Wildfire On Montane Stream Ecosystems In The Southern Rocky Mountains: One And Two Years Post-Burn, Sharon J. Hall, Danica Lombardozzi

Western North American Naturalist

The frequency and intensity of wildfire in the western United States has increased over the last century, creating a heterogeneous mosaic of landscapes in various stages of recovery. The 2002 Hayman Fire was one of the largest wildfires in Colorado history and was unprecedented for its speed and intensity, with over 50%–70% of the burn area classified as moderate to high severity where much of the canopy crown was consumed. We evaluated the short-term impact of the Hayman Fire on ecological properties in montane stream ecosystems in the summers of 2003 and 2004, one and two years post-fire. Fire significantly …

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Front Matter, Vol. 68 No. 4 Dec 2008

Front Matter, Vol. 68 No. 4

Western North American Naturalist

No abstract provided.

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Diet And Sexual Dimorphism Of The Desert Iguana, Dipsosaurus Dorsalis, From Sonora, Mexico, Christopher J. Dibble, Geoffrey R. Smith, Julio A. Lemos-Espinal Dec 2008

Diet And Sexual Dimorphism Of The Desert Iguana, Dipsosaurus Dorsalis, From Sonora, Mexico, Christopher J. Dibble, Geoffrey R. Smith, Julio A. Lemos-Espinal

Western North American Naturalist

We examined the diet and sexual dimorphism of the desert iguana, Dipsosaurus dorsalis, from Sonora, Mexico. The diet consisted primarily of vegetation, with insect material contributing little to the overall volume of the diet. Plant matter was restricted to leaves and seeds. Animal prey consisted mostly of ants, termites, and beetles. Males and females did not differ significantly in snout–vent length, head length, or head width. These results confirm that in general D. dorsalis is herbivorous and not sexually dimorphic through much of its range.


Examinamos la dieta y dimorfismo sexual de la Iguana del Desierto, Dipsosaurus dorsalis, en Sonora, …

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Towards The Total Synthesis Of Thioviridamide: Thiyl Radical Approach To The Beta-Thioenamide Linkage Formation, Jung-Hoon Kang Dec 2008

Towards The Total Synthesis Of Thioviridamide: Thiyl Radical Approach To The Beta-Thioenamide Linkage Formation, Jung-Hoon Kang

Theses and Dissertations

We developed an approach to the β-thioenamide linkage contained in the S-(2-aminovinyl)cysteine (avCys) residue of thioviridamide.1,2 Kinetic and thermodynamic control of radical additions of thiols to ynamides were studied for the formation of β-thioenamide linkage. Thiyl radicals are electrophilic and ynamides are electron-rich alkynes. This complementary polarity of the radical and acceptor increases the likelihood of a successful radical addition reaction. Because little is known about these types of compounds (β-thioenamides), we were unsure what kinds of yields and stereoselectivities (cis vs. trans) to expect. The adduct stability is another issue to consider. Fortunately, under typical radical addition conditions, the …

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Utilitizing And Moving Beyond A Constructionist Approach To Trace The Emergence Of Racial And Ethnic Identities Among Pre-Mexican, Mexican And Americans Of Mexican Descent, Owen Williamson Dec 2008

Utilitizing And Moving Beyond A Constructionist Approach To Trace The Emergence Of Racial And Ethnic Identities Among Pre-Mexican, Mexican And Americans Of Mexican Descent, Owen Williamson

Theses and Dissertations

Cornell and Hartmann (2007) developed a constructionist framework that can describe the development of racial and ethnic identities. Yet this framework has greater utility than its authors have intended as it also provides the best rubric to date for comprehending the transitions between collective identity group types. This study engages in a thorough investigation of the development of racial and ethnic identities within the context of those that precede it via an ethnohistorical analysis. It also demonstrates that this framework is capable of describing pre-modern religious and national identity types in addition to racial and ethnic identity types. This permits …

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Ontology Generation, Information Harvesting And Semantic Annotation For Machine-Generated Web Pages, Cui Tao Dec 2008

Ontology Generation, Information Harvesting And Semantic Annotation For Machine-Generated Web Pages, Cui Tao

Theses and Dissertations

The current World Wide Web is a web of pages. Users have to guess possible keywords that might lead through search engines to the pages that contain information of interest and browse hundreds or even thousands of the returned pages in order to obtain what they want. This frustrating problem motivates an approach to turn the web of pages into a web of knowledge, so that web users can query the information of interest directly. This dissertation provides a step in this direction and a way to partially overcome the challenges. Specifically, this dissertation shows how to turn machine-generated web …

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Learning-Based Fusion For Data Deduplication, Sabra Dinerstein, Parris K. Egbert, Stephen W. Clyde, Jared Dinerstein Dec 2008

Learning-Based Fusion For Data Deduplication, Sabra Dinerstein, Parris K. Egbert, Stephen W. Clyde, Jared Dinerstein

Faculty Publications

Rule-based deduplication utilizes expert domain knowledge to identify and remove duplicate data records. Achieving high accuracy in a rule-based system requires the creation of rules containing a good combination of discriminatory clues. Unfortunately, accurate rule-based deduplication often requires significant manual tuning of both the rules and the corresponding thresholds. This need for manual tuning reduces the efficacy of rule-based deduplication and its applicability to real-world data sets. No adequate solution exists for this problem. We propose a novel technique for rule-based deduplication. We apply individual deduplication rules, and combine the resultant match scores via learning-based information fusion. We show empirically …

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Does Shape Predict Performance? An Analysis Of Morphology And Swimming Performance In Great Basin Fishes, John R. Aedo Dec 2008

Does Shape Predict Performance? An Analysis Of Morphology And Swimming Performance In Great Basin Fishes, John R. Aedo

Theses and Dissertations

Swimming performance strongly influences fitness in aquatic organisms and is closely tied to external body morphology. Although this connection has been closely examined at the individual and species level, few studies have focused on this relationship as it pertains to functional group assemblages. Using functional groups based on similarities in habitat use and morphology, I tested the hypothesis that swimming performance can be reliably predicted by functional group composition. I measured swimming performance as burst speed using a simulated predator attack and as prolonged speed using a step-endurance test in a laboratory flume. I measured morphology using geometric morphometric techniques. …

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A Population Genetic Study Of Middle Eastern Populations Using Dys 458 Microvariants And Cohen Modal Haplotypes, Enass Nabeel Tinah Dec 2008

A Population Genetic Study Of Middle Eastern Populations Using Dys 458 Microvariants And Cohen Modal Haplotypes, Enass Nabeel Tinah

Theses and Dissertations

A comprehensive population study in the Middle East was conducted using different genetic markers in order to establish a wider genetic profile of the Middle Eastern populations. The main goal of this study was to analyze DNA from samples collected from different locations, and produce genetic motifs and patterns that could be used to identify and distinguish the target populations. This information will allow us to analyze the ancestry of these populations, their interactions through time and space, and the effects these interactions have on the populations' structure. We have collected around 1300 individual samples from different populations in the …

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The Effects Of Excess Corticosterone On Lkb1 And Ampk Signaling In Skeletal Muscle Of Rats, Gary N. Nakken Dec 2008

The Effects Of Excess Corticosterone On Lkb1 And Ampk Signaling In Skeletal Muscle Of Rats, Gary N. Nakken

Theses and Dissertations

Cushing's syndrome and glucocorticoid therapy lead to central obesity, insulin resistance, and symptoms of altered energy regulation similar to those observed in the metabolic syndrome. We hypothesized that excess glucocorticoids alter energy sensing/signaling in skeletal muscle through mediation of the LKB1/AMPK signaling pathway. To test this hypothesis, three 100 mg pellets of corticosterone were implanted subcutaneously in each of nine rats for two weeks. Responses were compared with sham operated controls fed ad libitum or food restricted to produce the body weights similar to the treatment group rats. After the treatment period, animals were anesthetized and the right gastrocnemius-plantaris and …

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Assessing Water Quality Modeling In Subtropical Regions Based On A Case Study Of The Aguamilpa Reservoir, Oliver Obregon Dec 2008

Assessing Water Quality Modeling In Subtropical Regions Based On A Case Study Of The Aguamilpa Reservoir, Oliver Obregon

Theses and Dissertations

The shortage of water in Mexico has made public and private institutions look at reservoirs as an alternative solution for present and future water supply. However, eighty percent of the existing reservoirs in Mexico are contaminated at some level, many severely. Water quality models are water-management tools used to diagnose water quality problems and the impact of various environmental conditions. They can be effective in assessing various measures of remediation leading to improved water quality. In most of the cases such water quality models have been successfully applied in reservoirs located in temperate climates. However, the use of water quality …

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Film Families: The Portrayal Of The Family In Teen Films From 1980 To 2007, Caroline Clayton Clark Dec 2008

Film Families: The Portrayal Of The Family In Teen Films From 1980 To 2007, Caroline Clayton Clark

Theses and Dissertations

American adolescents watch an average of 3.5 hours of television and movies everyday; many attend more than one movie a month. Adolescents as a group watch more movies than any other group of the population, yet little research has been done on what is shown in teen movies. Adolescence is a time when values, beliefs, and opinions are formed and the media has been found to be a place that adolescents find information that can influence the construction of these identities. While there has been a vast amount of research looking at the family as portrayed on television shows, there …

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Sequence Alignment With Traceback On Reconfigurable Hardware, Scott Lloyd, Quinn O. Snell Dec 2008

Sequence Alignment With Traceback On Reconfigurable Hardware, Scott Lloyd, Quinn O. Snell

Faculty Publications

Biological sequence alignment is an essential tool used in molecular biology and biomedical applications. The growing volume of genetic data and the complexity of sequence alignment present a challenge in obtaining alignment results in a timely manner. Known methods to accelerate alignment on reconfigurable hardware only address sequence comparison, limit the sequence length, or exhibit memory and I/O bottlenecks. A space-efficient, global sequence alignment algorithm and architecture is presented that accelerates the forward scan and traceback in hardware without memory and I/O limitations. With 256 processing elements in FPGA technology, a performance gain over 300 times that of a desktop …

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Real-Time Automatic Price Prediction For Ebay Online Trading, Ilya Igorevitch Raykhel Nov 2008

Real-Time Automatic Price Prediction For Ebay Online Trading, Ilya Igorevitch Raykhel

Theses and Dissertations

While Machine Learning is one of the most popular research areas in Computer Science, there are still only a few deployed applications intended for use by the general public. We have developed an exemplary application that can be directly applied to eBay trading. Our system predicts how much an item would sell for on eBay based on that item's attributes. We ran our experiments on the eBay laptop category, with prior trades used as training data. The system implements a feature-weighted k-Nearest Neighbor algorithm, using genetic algorithms to determine feature weights. Our results demonstrate an average prediction error of 16%; …

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Design And Testing Of A Pumpless Microelectromechanical System Nanoinjector, Quentin Theodore Aten Nov 2008

Design And Testing Of A Pumpless Microelectromechanical System Nanoinjector, Quentin Theodore Aten

Theses and Dissertations

A deeper understanding of human development and disease is made possible partly through the study of genetically modified model organisms, such as the common mouse (Mus musculus). By genetically modifying such model organisms, scientists can activate, deactivate, or highlight particular characteristics. A genetically modified animal is generated by adding exogenous (foreign) genetic material to one or more embryonic cells at their earliest stages of development. Frequently, this exogenous genetic material consists of specially engineered DNA, which is introduced into a fertilized egg cell (zygote). When successfully introduced into the zygote, the exogenous DNA will be incorporated into the …

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The Promise Of Academic Learning Time In A Dose-Response Model Of Early Reading Achievement, Benjamin Heuston Nov 2008

The Promise Of Academic Learning Time In A Dose-Response Model Of Early Reading Achievement, Benjamin Heuston

Theses and Dissertations

Reading has long been acknowledged to be a critical skill that is best acquired early in life. According to the most recent National Assessment of Educational Progress (NAEP) reports, American public school children continue to struggle to master the basics of reading. Although federal funding in real dollars has increased consistently over time, reading scores have not followed suit, suggesting that fiscal resources have not been applied successfully to the variables that are directly related to reading acquisition and achievement. The current state of affairs therefore suggests the need for identifying a fiscally-targetable, instructionally-relevant variable with a direct, causal relationship …

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Evolution Of Picornaviruses: Impacts Of Recombination And Selection, Nicole Noel Lewis-Rogers Nov 2008

Evolution Of Picornaviruses: Impacts Of Recombination And Selection, Nicole Noel Lewis-Rogers

Theses and Dissertations

Picornaviruses are responsible for some of the most common and debilitating diseases affecting humans and animals worldwide. The objectives of this dissertation research were (1) estimate phylogenetic relationships among 11 picornavirus genera and within three species: foot-and-mouth disease virus (FMDV: Aphthovirus) which afflicts cloven-hoofed animals and human rhinovirus A and B (HRV: Enterovirus) which cause the common cold; (2) better understand the impact recombination has on genomic organization and evolution; (3) characterize where positive and purifying selection has occurred in proteins and how selection has influenced phenotype. The dissertation includes four studies. The first chapter provides an overview of the …

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Hair, Feces And Breath Isotope Fractionation In Alpacas (Llama Pacos), Llamas (Llama Glama) And Guanacos (Llama Guanacoe) From Bolivia And Chile, Lino Constancio Lopez Lopez Nov 2008

Hair, Feces And Breath Isotope Fractionation In Alpacas (Llama Pacos), Llamas (Llama Glama) And Guanacos (Llama Guanacoe) From Bolivia And Chile, Lino Constancio Lopez Lopez

Theses and Dissertations

This study was conducted to determinate carbon and nitrogen isotope fractionation in Bolivian and Chilean alpaca, llama and guanaco, hair, breath, plasma and feces. We also wanted to determine forage selection for these camelids using stable isotope technology. From the data, niche feeding and diet selection habits will determinate based on fecal composition. Bolivian sites were located near the high snow Altiplano Mountains at Tomarapi, Sajama, and at the Technical University Oruro's research center at Condoriri, Bolivia. Chilean samples were collected at INIA's (Instituto Nacional de Investigacion Agropecuaria) Kampenaike Research Station, Punta Arenas, Chile. Bolivian alpacas and llamas were 3 …

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Specific Compartmentalization Of Iga Ascs In Mouse Salivary Glands Via Differential Expression Of Chemokines And Chemokine Receptors, Yuet Ching Law Nov 2008

Specific Compartmentalization Of Iga Ascs In Mouse Salivary Glands Via Differential Expression Of Chemokines And Chemokine Receptors, Yuet Ching Law

Theses and Dissertations

The mucosal system, which forms a barrier between internal organ systems and the external environment, is frequently exposed to pathogenic microorganisms. Immunoglobulin A (IgA) antibody secreting cells (ASCs) localize in the lamina propria, and produce IgA antibodies which help protect mucosal tissues. The concept of a common mucosal immune system in which IgA ASCs have the ability to populate any mucosal site has been proposed (1, 2). However, recent research has suggested that IgA ASCs primed in different mucosal sites might possess different sets of chemokine receptors, and therefore migrate specifically to particular mucosal locations (3). In this study, the …

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Semantic Role Agency In Perceptions Of The Lexical Items Sick And Evil, Nathan G. Simmons Nov 2008

Semantic Role Agency In Perceptions Of The Lexical Items Sick And Evil, Nathan G. Simmons

Theses and Dissertations

Inspired by an ongoing debate in the clinical sciences concerning the value of evil as a label for human behavior (Mowrer 1960, Staub 1999, Wellman 2000, Williams 2004 etc.), this thesis examines the semantic role of AGENT in the lexical items sick and evil. Williams makes the argument that the label evil removes responsibility from the doctor, whereas, the label sick empowers the doctor in bringing about a cure. While this view is not universally accepted in the field, it does bring to light an interesting question in applied linguistic semantics as to the assignment of agency with respect to …

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Comprehension And Retention: The Effect Of Concrete Details And Causal Structure In Scientific Narrative, Wendi Michelle Wilcken Nov 2008

Comprehension And Retention: The Effect Of Concrete Details And Causal Structure In Scientific Narrative, Wendi Michelle Wilcken

Theses and Dissertations

The purpose of this study was to examine two of the salient elements of instructional narratives as a guide to instructional practice. The literature summarized in this report discusses the theoretical basis for narrative impact on comprehension and retention, enumerates and defines possible salient narrative elements from the literature, and examines the instructional impact of two of these elements: concrete details and causal structure. This is intended to help provide guidance to instructional designers and teachers who desire to use narrative in science instruction. Participants included 94 high school physics students. An experimental research design of 2 (Gender) x 2 …

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