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Brigham Young University

2006

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Long-Term Effects Of Tebuthiuron On Bromus Tectorum, Dana M. Blumenthal, Urszula Norton, Justin D. Derner, Jean D. Reeder Dec 2006

Long-Term Effects Of Tebuthiuron On Bromus Tectorum, Dana M. Blumenthal, Urszula Norton, Justin D. Derner, Jean D. Reeder

Western North American Naturalist

Use of herbicides to thin dense stands of Artemisia spp. (sagebrush) can free up resources for herbaceous plants and increase forage production, but may also facilitate weed invasion. We revisited a sagebrush thinning experiment in a north central Wyoming big sagebrush–grassland 11 years after application of tebuthiuron (N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N-N′-dimethylurea) to determine the long-term responses of shrubs, available soil resources, perennial grasses, and Bromus tectorum L. (downy brome). Tebuthiuron reduced shrub cover by more than half, from 31% in untreated plots to 15% in treated plots (P = 0.002), and increased downy brome cover approximately 4-fold, from 0.9% in untreated plots …

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Long-Term Interactions Of Climate, Productivity, Species Richness, And Growth Form In Relictual Sagebrush Steppe Plant Communities, Neil E. West, Terence P. Yorks Dec 2006

Long-Term Interactions Of Climate, Productivity, Species Richness, And Growth Form In Relictual Sagebrush Steppe Plant Communities, Neil E. West, Terence P. Yorks

Western North American Naturalist

Vegetation trends due to climatic changes are difficult to separate from disturbances caused by varying land uses. To separate climatic influences from livestock grazing and fire disturbances within sagebrush steppe, we compared vegetation structure and productivity during 2 periods (10-year sequences of data from the late 1950s to the late 1960s and 3 years in the early 1990s) at 12 stands within 3 relict areas in or near the Great Rift of southern Idaho. Year-to-year fluctuations in annual net aboveground phytomass accumulation (ANAPA) were considerable in response to varying climate during both periods. More importantly, an apparently significant increase in …

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Stand-Level Herbivory In An Old-Growth Conifer Forest Canopy, David C. Shaw, Kristina A. Ernest, H. Bruce Rinker, Margaret D. Lowman Dec 2006

Stand-Level Herbivory In An Old-Growth Conifer Forest Canopy, David C. Shaw, Kristina A. Ernest, H. Bruce Rinker, Margaret D. Lowman

Western North American Naturalist

Herbivory is an important ecological process in forest canopies but is difficult to measure, especially for whole stands. We used the Wind River Canopy Crane in Washington State to access 101 randomly-located sample points throughout the forest canopy. This provided a relatively quick and convenient way to estimate herbivory for a whole stand. The overall level of herbivory was estimated at 1.6% of leaf area. The distribution was strongly skewed to the lower canopy where broad-leafed species experienced higher levels of herbivory. Herbivory averaged 0.3% in conifers and 13.5% in broad-leafed species. Fully half of the sample points had no …

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Populations And Habitat Relationships Of Piute Ground Squirrels In Southwestern Idaho, Karen Steenhof, Eric Yensen, Michael N. Kochert, Kenneth L. Gage Dec 2006

Populations And Habitat Relationships Of Piute Ground Squirrels In Southwestern Idaho, Karen Steenhof, Eric Yensen, Michael N. Kochert, Kenneth L. Gage

Western North American Naturalist

Piute ground squirrels (Spermophilus mollis idahoensis) are normally above ground from late January until late June or early July in the Snake River Birds of Prey National Conservation Area in southwestern Idaho. In 2002 they were rarely seen above ground after early May. Because of the ecological importance of ground squirrels for nesting raptors and other species, we sought to determine the reasons for their early disappearance. We sampled 12 sites from January 2003 through March 2003 to determine if a population crash had occurred in 2002. Tests indicated that Piute ground squirrels had not been exposed to …

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Serologic Survey Of The Island Spotted Skunk On Santa Cruz Island, Victoria J. Bakker, Dirk H. Van Vuren, Kevin R. Crooks, Cheryl A. Scott, Jeffery T. Wilcox, David K. Garcelon Dec 2006

Serologic Survey Of The Island Spotted Skunk On Santa Cruz Island, Victoria J. Bakker, Dirk H. Van Vuren, Kevin R. Crooks, Cheryl A. Scott, Jeffery T. Wilcox, David K. Garcelon

Western North American Naturalist

Two rare endemic carnivores occur on California's northern Channel Islands: island spotted skunks (Spilogale gracilis amphiala) and island foxes (Urocyon littoralis). As insular carnivores, both may be particularly vulnerable to novel pathogens. We tested sera from 31 island spotted skunks on Santa Cruz Island, where both skunks and foxes occur sympatrically, to establish their exposure to disease agents. One skunk (3%) tested positive for canine heartworm, and 3 skunks (10%) tested positive for canine parvovirus. None showed evidence of exposure to canine adenovirus, canine distemper virus, canine herpesvirus, Leptospira bacteria (serovars pomona, canicola, and …

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Ecology Of Owens Valley Vole (Microtus Californicus Vallicola), Fletcher C. Nelson, Michael L. Morrison, Roel R. Lopez, Fred E. Smeins, Nova J. Silvy Dec 2006

Ecology Of Owens Valley Vole (Microtus Californicus Vallicola), Fletcher C. Nelson, Michael L. Morrison, Roel R. Lopez, Fred E. Smeins, Nova J. Silvy

Western North American Naturalist

No abstract provided.

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Invasion Biology: Critique Of A Pseudoscience By David Theodoropoulos, Howard Clark Dec 2006

Invasion Biology: Critique Of A Pseudoscience By David Theodoropoulos, Howard Clark

Western North American Naturalist

No abstract provided.

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Raptors Of California By Hans Peeters And Pam Peeters, Clayton M. White Dec 2006

Raptors Of California By Hans Peeters And Pam Peeters, Clayton M. White

Western North American Naturalist

No abstract provided.

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End Matter, Vol. 66 No. 4 Dec 2006

End Matter, Vol. 66 No. 4

Western North American Naturalist

No abstract provided.

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Brain Stimulation Reward Is Integrated By A Network Of Electrically-Coupled Gaba Neurons, Matthew Brian Lassen Dec 2006

Brain Stimulation Reward Is Integrated By A Network Of Electrically-Coupled Gaba Neurons, Matthew Brian Lassen

Theses and Dissertations

Although it is well-established that animals will self-stimulate electric current to various diverse brain structures, the neural substrate of brain stimulation reward (BSR) has eluded identification since its discovery more than a half-century ago. We show that GABA neurons in the midbrain, hypothalamus and thalamus express connexin-36 (Cx36) gap junctions and couple electrically with dopamine application or by stimulation of the internal capsule (IC), which also supports self-stimulation. The threshold for responding for self-stimulation of the IC is the threshold for coupling between these GABA neurons, the degree of responding for IC ICSS is proportional to the magnitude of electrical …

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Evolution In Neotropical Herpetofauna: Species Boundaries In High Andean Frogs And Evolutionary Genetics In The Lava Lizard Genus Microlophus (Squamata: Tropiduridae): A History Of Colonization And Dispersal, Edgar Benavides Dec 2006

Evolution In Neotropical Herpetofauna: Species Boundaries In High Andean Frogs And Evolutionary Genetics In The Lava Lizard Genus Microlophus (Squamata: Tropiduridae): A History Of Colonization And Dispersal, Edgar Benavides

Theses and Dissertations

In this collection of papers I have summarized my investigations into the field of evolutionary genetics and more specifically into patterns of biodiversity and evolutionary processes. The lizards (and frogs) studied here share common features in that they are largely present in unique environments, which are also regions that are biologically understudied. Most of these taxa show high degrees of endemism, interesting natural history characteristics, and each group manifests distinctive adaptations of general evolutionary interest. My work in the genus Telmatobius has been a progressive approach that began in my MS program, and it first focused on alpha taxonomy, morphological …

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Analysis Of Near-Infrared Phase Effects On Biometric Iris Data, Brady Roos Stevenson Dec 2006

Analysis Of Near-Infrared Phase Effects On Biometric Iris Data, Brady Roos Stevenson

Theses and Dissertations

The purpose of this research is to ascertain potential iris scan data variations from near infrared waves derived from fluorescent illumination. Prior studies of iris data variances from infrared wave interference of halogen, incandescent, and sunlight with iris cameras suggest that similar changes may exist under near infrared wavelengths from fluorescent light. The concern is that the fluorescent energy emission may interfere with the near infrared detection of an iris camera. An iris camera is used to measure human eye characteristics known as biometrics. If such infrared emission is statistically significant, then it can alter the validity of the iris …

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A Dynamic Workflow Framework For Mass Customization Using Web Service And Autonomous Agent Technologies, Daniel J. Karpowitz Dec 2006

A Dynamic Workflow Framework For Mass Customization Using Web Service And Autonomous Agent Technologies, Daniel J. Karpowitz

Theses and Dissertations

Custom software development and maintenance is one of the key expenses associated with developing automated systems for mass customization. This paper presents a method for reducing the risk associated with this expense by developing a flexible environment for determining and executing dynamic workflow paths. Strategies for developing an autonomous agent-based framework and for identifying and creating web services for specific process tasks are presented. The proposed methods are outlined in two different case studies to illustrate the approach for both a generic process with complex workflow paths and a more specific sequential engineering process.

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A Torque Based Power Input Model For Friction Stir Welding, Jefferson W. Pew Dec 2006

A Torque Based Power Input Model For Friction Stir Welding, Jefferson W. Pew

Theses and Dissertations

For decades models have been developed for predicting the size of the weld nugget and heat affected zones in fusion welded structures. The basis for these models is the welding heat input, which is fairly well understood for most arc welding processes. However, this traditional approach is not as straightforward for Friction Stir Welding (FSW). To date, there is no definitive relationship to quantify the heat input for FSW. An important step to establish a heat input model is to identify how FSW process parameters affect weld power. This study details the relationship between FSW process parameters and torque for …

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Design And Construction Of Pavements In Cold Regions: State Of The Practice, Brad Steven Smith Dec 2006

Design And Construction Of Pavements In Cold Regions: State Of The Practice, Brad Steven Smith

Theses and Dissertations

The effects of frost action introduce many challenges in the design and construction of roadways in cold regions throughout the United States. The penetration of frost into pavement structures can lead to differential frost heave during winter and thaw weakening during spring. Both of these damage mechanisms lead to premature pavement distress, structural deterioration, and poor ride quality. Because the availability of naturally occurring non-frost-susceptible pavement base materials is rapidly diminishing in many areas while project budgets remain largely inadequate, pavement engineers are utilizing alternative materials and techniques to minimize such damage. The purpose of this research was to investigate …

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Shape Matching, Relevance Feedback, And Indexing With Application To Spine X-Ray Image Retrieval, Xiaoqian Xu Dec 2006

Shape Matching, Relevance Feedback, And Indexing With Application To Spine X-Ray Image Retrieval, Xiaoqian Xu

Theses and Dissertations

The National Library of Medicine (NLM), an institute in the National Institutes of Health (NIH), maintains a collection of 17,000 digitized spine X-ray images obtained from the second National Health and Nutrition Examination Survey (NHANES II). Research effort has been devoted to develop a web-accessible retrieval system that allows retrieval of images from the NHANES II database on relevant and frequently found pathologies. A comprehensive and successful image retrieval system requires effective image representation and matching methods, relevance feedback algorithms to incorporate user opinions, and efficient indexing schemes for fast access to image databases. This dissertation studies and develops approaches …

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An Analysis Of The Accounting Methods Used By Builders Producing Twenty-Five Or Fewer Homes Per Year, David Andrus Dec 2006

An Analysis Of The Accounting Methods Used By Builders Producing Twenty-Five Or Fewer Homes Per Year, David Andrus

Theses and Dissertations

Accounting plays a crucial role in the success of any business, but it is particularly vital in the construction industry, a complex field that typically requires the coordination of multiple subcontractors and multiple jobs in any given year. Although small-volume home builders make up 70 percent of the membership of the National Association of Home Builders (NAHB), a trade association of the home building industry, little is known about the accounting practices of these builders. This thesis undertook to study the accounting practices of small-volume home builders. Small-volume home builders were defined as those producing 25 homes or fewer in …

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The Birth Of Sacrifice: Iconographic Metaphors For Spiritual Rebirth In Master Matthias' Isenheim Altarpiece, Katherine Lena Anderson Dec 2006

The Birth Of Sacrifice: Iconographic Metaphors For Spiritual Rebirth In Master Matthias' Isenheim Altarpiece, Katherine Lena Anderson

Theses and Dissertations

While little is known concerning the events surrounding the commission of the Isenheim Altarpiece or of the artist known to us as Master Matthias Grünewald, much can be ascertained about the message of the Altarpiece through careful study of the socio-historical-religious context from which the work was commissioned and iconographic analysis of the images portrayed by Master Matthias. This thesis explores iconographic metaphors for birth and sacrifice, metaphors which work to create a theological dialogue about Christian redemption within the nine painted panels and the underlying sculpture that makes up the Isenheim Altarpiece. First, we will address the panels in …

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Large 3-D Deflection And Force Analysis Of Lateral Torsional Buckled Beams, Robert Parley Chase Dec 2006

Large 3-D Deflection And Force Analysis Of Lateral Torsional Buckled Beams, Robert Parley Chase

Theses and Dissertations

This thesis presents research on the force and deflection behavior of beams with rectangular cross-sections undergoing lateral torsional buckling. The large 3-D deflection path of buckling beam tips was closely approximated by circular arcs in two planes. A new chain algorithm element was created from pseudo-rigid-body segments and used in a chain calculation that accurately predicted the force deflection relationship of beams with large 3-D deflections.

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Pilgrimage Narrative: A Pattern For Heavenly Theatre In King Lear, Alexandra Chantal Yvette Mackenzie Dec 2006

Pilgrimage Narrative: A Pattern For Heavenly Theatre In King Lear, Alexandra Chantal Yvette Mackenzie

Theses and Dissertations

I have always felt personally challenged and invigorated by one line in Peter Brook's canonical text The Empty Stage: “if the need for a true contact with a sacred invisibility through the theatre still exists, then all possible vehicles must be re-examined" (Brook 54). This thesis will endeavour to suggest and explore heavenly theatre, one possible vehicle to find that sacred invisibility. I will argue that heavenly theatre encompasses Peter Brook's understanding of holy theatre, but is more specific and tied to the manifestation of deity in the form of the Holy Spirit as understood and defined within my personal …

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Using Duplication With Compare For On-Line Error Detection In Fpga-Based Designs, Daniel L. Mcmurtrey Dec 2006

Using Duplication With Compare For On-Line Error Detection In Fpga-Based Designs, Daniel L. Mcmurtrey

Theses and Dissertations

Space destined FPGA-based systems must employ redundancy techniques to account for the effects of upsets caused by radiated environments. Error detection techniques can be used to alert external systems to the presence of these upsets. Readback with compare is an error detection technique commonly employed in FPGA-based designs. This work introduces duplication with compare (DWC) as an automated on-line error detection technique that can be used as an alternative to readback with compare. This work also introduces a set of metrics that is used to quantify the effectiveness and coverage of this error detection technique. A tool is presented that …

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Life Data Analysis Of Repairable Systems: A Case Study On Brigham Young University Media Rooms, Stephen Oluaku Manortey Dec 2006

Life Data Analysis Of Repairable Systems: A Case Study On Brigham Young University Media Rooms, Stephen Oluaku Manortey

Theses and Dissertations

It is an undisputable fact that most systems, upon consistence usage are bound to fail in the performance of their intended functions at a point in time. When this occurs, various strategies are set in place to restore them back to a satisfactory performance. This may include replacing the failed component with a new one, swapping parts, resetting adjustable parts to mention but a few. Any such system is referred to as a repairable system. There is the need to study these systems and use statistical models to predict their failing time and be able to set modalities in place …

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A Bayesian Perspective On Estimating Mean, Variance, And Standard-Deviation From Data, Travis E. Oliphant Dec 2006

A Bayesian Perspective On Estimating Mean, Variance, And Standard-Deviation From Data, Travis E. Oliphant

Faculty Publications

This article shows how to compute confidence intervals for mean, standard-deviation, and variance using Bayesian methods. The method is implemented in SciPy as scipy.stats.bayes_mvs After reviewing some classical estimators for mean, variance, and standard-deviation and showing that un-biased estimates are not usually desirable, a Bayesian perspective is employed to determine what is known about mean, variance, and standard deviation given only that a data set in-fact has a common mean and variance. Maximum-entropy is used to argue that the likelihood function in this situation should be the same as if the data were independent and identically distributed Gaussian. A non-informative …

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Forage Adaptability Trials For Forage And Seed Production In Bolivia; Effect Of 5 Herbicides On 7 Native Utah Forbs, Joshua C. Voss Dec 2006

Forage Adaptability Trials For Forage And Seed Production In Bolivia; Effect Of 5 Herbicides On 7 Native Utah Forbs, Joshua C. Voss

Theses and Dissertations

The harsh environmental and poor economic conditions of the Bolivian Altiplano require intervention to assist many of those that live there to become economically self-sufficient. We attempted to find introduced dry season reserve forage grasses that could produce enough biomass to be useful as feed for livestock, and that could also produce enough seed to distribute to farmers. While some of the grasses produced reasonable amounts of biomass, none produced seed in quantities that would be even close to being economically viable. The most likely cause of this is that the timing of resources that the grasses need to flower …

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Development Of Polymer Monoliths For The Analysis Of Peptides And Proteins, Binghe Gu Dec 2006

Development Of Polymer Monoliths For The Analysis Of Peptides And Proteins, Binghe Gu

Theses and Dissertations

Several novel polymer monoliths for the analysis of peptides and proteins were synthesized using polyethylene glycol diacrylate (PEGDA) as crosslinker. Photo-initiated copolymerization of polyethylene glycol methyl ether acrylate and PEGDA yielded an inert monolith that could be used for size exclusion liquid chromatography of peptides and proteins. This macroscopically uniform monolith did not shrink or swell in either water or tetrahydrofuran. More importantly, it was found to resist adsorption of both acidic and basic proteins in aqueous buffer without any organic solvent additives. A strong cation-exchange polymer monolith was synthesized by copolymerization of 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) and PEGDA. A ternary …

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Effects Of Telephone Weight Loss Coaching On Body Composition In Adults: A Randomized Controlled Study, Amy Jensen Cook Dec 2006

Effects Of Telephone Weight Loss Coaching On Body Composition In Adults: A Randomized Controlled Study, Amy Jensen Cook

Theses and Dissertations

Objective: To determine the extent to which coaching over the telephone is an effective method in promoting the loss of body weight and body fat percentage. Research Methods and Procedures: Over a period of four months, in a randomized, double blind, placebo-controlled study, 120 overweight and obese (BMI 25-35 kg/m²) adults either received telephone coaching or no coaching. In addition, each participant was randomly assigned to take a supplement or placebo daily. Body weight and body fat percentage were measured at baseline, two months, and four months. Body weight was measured on an electronic scale and body fat percentage was …

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The Role Of Wnt Signaling In Development Of The Ophthalmic Trigeminal Placode., Rhonda Nicole Lassiter Dec 2006

The Role Of Wnt Signaling In Development Of The Ophthalmic Trigeminal Placode., Rhonda Nicole Lassiter

Theses and Dissertations

Cranial placodes are ectodermal regions that contribute extensively to the vertebrate peripheral nervous system. The development of the ophthalmic trigeminal (opV) placode, which gives rise only to sensory neurons of the ophthalmic lobe of the trigeminal ganglion, is a well-studied model of sensory neuron development. While key differentiation processes have been characterized at the tissue and cellular levels, the molecules governing opV placode development have not been well described. This study identifies the canonical Wnt signaling pathway as a regulator of opV trigeminal placode development. Introducing dominant-negative TCF and dominant-active β-catenin expression constructs by in ovo electroporation, we have manipulated …

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Synthesis And Optical Properties Of Four Oligothiophene-Ruthenium Complexes And Synthesis Of A Bidentate Ligand For C-F Bond Activation, Joseph S. Bair Dec 2006

Synthesis And Optical Properties Of Four Oligothiophene-Ruthenium Complexes And Synthesis Of A Bidentate Ligand For C-F Bond Activation, Joseph S. Bair

Theses and Dissertations

Photovoltaic cells and fluorescence sensing are two important areas of research in chemistry. The combination of photon-activated electron donors with electron acceptors provides a strong platform for the study of optical devices. A series of four oligothiophene-ruthenium complexes has been synthesized. Variation in oligothiophene length and bipyridine substitution allowed comparison of these variables on electronic properties. The longer oligothiophenes display lower energy absorption and emission compared to the shorter ones. Aromatic conjugation appears more complete with para-, rather than meta-, substitution. Oligothiophenes and Ru(bpy)32+ are highly fluorescent individually, but fluorescence is quenched when connected. Bonds of carbon to fluorine are …

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Using Social Network Analysis To Investigate Potential Bias In Editorial Peer Review In Core Journals Of Comparative/International Education, Biao Cheng Dec 2006

Using Social Network Analysis To Investigate Potential Bias In Editorial Peer Review In Core Journals Of Comparative/International Education, Biao Cheng

Theses and Dissertations

This study explores potential bias in the editorial peer-review system within the context of the field of comparative and international education. Assuming the role as “Guardian of Science” and “social status judge” (Zuckerman & Merton, 1971), peer-review, the quality control system of science, directly affects the growth of science, scientists' academic career and their institutions. The very basic tenet of the peer review system is its assumed objectivity. Bias in editorial peer review process, however, is inevitable. The constitution of the blind peer review mechanism is itself a simply undeniable acknowledgement of that fact. Therefore, this study investigated potential peer-review …

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Charting The Future Of Brigham Young University: Franklin S. Harris And The Changing Landscape Of The Church's Educational Network, 1921-1926, J. Gordon Daines Iii Dec 2006

Charting The Future Of Brigham Young University: Franklin S. Harris And The Changing Landscape Of The Church's Educational Network, 1921-1926, J. Gordon Daines Iii

BYU Studies Quarterly

Education is deeply embedded in the theology and religion of The Church of Jesus Christ of Latter-day Saints. Formal educational systems began to develop soon after the establishment of the Church in 1830. The first of these formal systems was the School of the Prophets, established in Kirtland, Ohio, in December 1832 to prepare selected members for missionary work. Nearly a decade later an attempt was made to establish a university in Nauvoo, Illinois. After the move to Utah, the Church continued its involvement in formal education with the establishment of “common schools, stake academies, and colleges and universities.” The …

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