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11th Annual Joseph C. Andrews Mentoring Breakfast, February 2, 2006, Black Faculty And Staff Association Jan 2006

11th Annual Joseph C. Andrews Mentoring Breakfast, February 2, 2006, Black Faculty And Staff Association

BFSA Collection - Mentoring Breakfast Materials

No abstract provided.

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Computer-Based Instructional Systems Design Tools: Current State And Implications For The Future, Anna A. Andrews Jan 2006

Computer-Based Instructional Systems Design Tools: Current State And Implications For The Future, Anna A. Andrews

Electronic Theses and Dissertations

This study examines the current state of computer-based instructional systems design (ISD) tools and outlines its implications for the future. The study utilizes the grounded theory methodology to capture and document modern instructional designers' perspectives regarding the current state of ISD tools, the issues associated with them, and their interrelationships. The study also presents a framework for classifying modern ISD tools and a conceptual prototype of a designer-oriented system of computer-based ISD tools.

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Enhancing Vocabulary Acquisition Through Synthetic Learning Experiences: Implementing Virtual Field Trips Into Classrooms, Alicia Sanchez Jan 2006

Enhancing Vocabulary Acquisition Through Synthetic Learning Experiences: Implementing Virtual Field Trips Into Classrooms, Alicia Sanchez

Electronic Theses and Dissertations

A Synthetic Learning Environment (SLE) the Virtual Field Trip (VFT) was designed to increase vocabulary acquisition and knowledge by utilizing simulation based technologies and leveraging sound educational findings. Vocabulary acquisition is considered a prerequisite to becoming a good reader and therefore a critical predictor of academic and lifelong success for early learners, however, teachers report that students lack the real world knowledge required for vocabulary knowledge. The VFT provides a meaningful context for anchored and situated instruction. Second grade students were assigned to either use the VFT or to listen to stories read aloud by a researcher on a video …

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The Effect Of School Culture On Science Education At An Elementary School: An Ethnographic Case Study, Lori Meier Jan 2006

The Effect Of School Culture On Science Education At An Elementary School: An Ethnographic Case Study, Lori Meier

Electronic Theses and Dissertations

This ethnographic case study investigated one elementary school to understand how the school's culture influenced its science curriculum design and instruction. The main data was formal and informal semi-structured interviews with key teachers to understand their values, beliefs, practices, materials, and problems with science instruction. To triangulate these data, the researcher observed classroom practice, school-wide activities, and collected artifacts and documents. Data were analyzed using a theoretical framework that emphasizes that culture cannot be reduced to beliefs, values, practices, materials or problems, but rather each aspect of culture is interdependent and mutually reinforcing. The main finding suggests that the school's …

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Identification Of System Design Features That Affect Sickness In Virtual Environments, Julie Drexler Jan 2006

Identification Of System Design Features That Affect Sickness In Virtual Environments, Julie Drexler

Electronic Theses and Dissertations

The terms "simulator" and "VR" are typically used to refer to specific types of virtual environments (VEs) which differ in the technology used to display the simulated environment. While simulators and VR devices may offer advantages such as low cost training, numerous studies on the effects to humans of exposure to different VEs indicate that motion sickness-like symptoms are often produced during or after exposure to the simulated environment. These deleterious side effects have the potential to limit the utilization of VE systems if they jeopardize the health and/or safety of the user and create liability issues for the manufacturer. …

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The Evolution Of French Identity: A Study Of The Huguenots In Colonial South Carolina, 1680-1740, Nancy Maurer Jan 2006

The Evolution Of French Identity: A Study Of The Huguenots In Colonial South Carolina, 1680-1740, Nancy Maurer

Electronic Theses and Dissertations

This thesis examines the changes that occurred in the French identity of Huguenot immigrants to colonial Carolina. In their pursuit of prosperity and religious toleration, the Huguenots' identity evolved from one of French religious refugees to that of white South Carolinians. How and why this evolution occurred is the focus of this study. Upon arriving in the colony in the 1680s and 1690s, the Huguenots' identity was based on several common factors: their French language, their Calvinist religion, and their French heritage. As the immigrant group began to build their new lives in Carolina, these identifying factors began to disappear. …

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The Effects Of Perceptions Of Crowding On Juror Attitudes And Decision-Making, Charles Short Jan 2006

The Effects Of Perceptions Of Crowding On Juror Attitudes And Decision-Making, Charles Short

HIM 1990-2015

Previous studies have explored the effects of crowding on non-human animals, human communities, human behavior, and differential effects on men and women. This area of research demands greater attention. Much of the existing work was performed in the 1970s and 80s. Further, it seeks to operationalize crowding only in terms of density. This study is premised on the idea set forth by Freedman that crowding is not merely the number of individuals per unit of space, but rather a subjective feeling. This thesis looks beyond density to find the effects of crowding on juror attitudes and decision-making. Participants were placed …

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Challenging A Traditional Social Norm In A Second Grade Mathematics Classroom, Lisa Egendoerfer Jan 2006

Challenging A Traditional Social Norm In A Second Grade Mathematics Classroom, Lisa Egendoerfer

Electronic Theses and Dissertations

In an attempt to examine classroom dialogue within a second grade classroom, I encouraged students to participate in mathematics discussions without needing to raise their hands before speaking. I challenged this traditional social norm and established sociomathematical norms as the study progressed. My study showed the effects of this change on the dialogue of students in my classroom. Focus was placed on the participation in classroom discussions when traditional social and sociomathematical norms were in place as well as when new norms were established. The study helped determine the effects of student-centered dialogue on conceptual understanding as demonstrated in the …

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Working Memory, Search, And Signal Detection: Implications For Interactive Voice Response System Menu Design, Patrick Commarford Jan 2006

Working Memory, Search, And Signal Detection: Implications For Interactive Voice Response System Menu Design, Patrick Commarford

Electronic Theses and Dissertations

Many researchers and speech user interface practitioners assert that interactive voice response (IVR) menus must be relatively short due to constraints of the human memory system. These individuals commonly cite Miller's (1956) paper to support their claims. The current paper argues that these authors commonly misuse the information provided in Miller's paper and that hypotheses drawn from modern theories of working memory (e.g., Baddeley and Hitch, 1974) would lead to the opposite conclusion – that reducing menu length by creating a greater number of menus and a deeper structure will actually be more demanding on users' working memories and will …

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The Effect Of Social Presence On Teacher Technology Acceptance, Continuance Intention, And Performance In An Online Teacher Professional Development Course, Jo Smith Jan 2006

The Effect Of Social Presence On Teacher Technology Acceptance, Continuance Intention, And Performance In An Online Teacher Professional Development Course, Jo Smith

Electronic Theses and Dissertations

The purpose of this study was to determine if the Technology Acceptance Model (TAM) could explain the relationship between teacher's acceptance of an online teacher professional development course and their continuance intentions regarding online teacher professional development (oTPD). This study focused on the perceptions of the teachers as opposed to the design or implementation of oTPD. The participants (N=517) were mostly teachers (88.8%) enrolled in a statewide online course to provide classroom teachers with the latest knowledge of research-based instructional reading strategies. The course was offered over a 10-14 week period during the Spring 2006 semester through a public state …

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In Transition: An Activity Theoretical Analysis Examining Electronic Portfolio Tools' Mediation Of The Preservice Teacher's Authoring Experience, Rebecca Fiedler Jan 2006

In Transition: An Activity Theoretical Analysis Examining Electronic Portfolio Tools' Mediation Of The Preservice Teacher's Authoring Experience, Rebecca Fiedler

Electronic Theses and Dissertations

Co-chairs: Dr. Donna Baumbach Dr. Gail West Background: Electronic portfolios are increasingly used to make critical decisions about teacher candidates and program accreditation. Adoption rates for portfolios are at nearly 90% for schools, colleges, and departments of education (Salzman, Denner, & Harris, 2002). Over 50% of institutions who rated themselves or were nominated by others as exemplary users of electronic portfolios use web-based database-driven electronic portfolio systems (Strudler & Wetzel, 2005b; Wetzel & Strudler, 2005b). There is a paucity of theory-driven, systematic, rigorous research on electronic portfolios and a need for in-depth, context-aware research on such initiatives. Purpose: To explicate …

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A Focus Group Of Adolescent Haitian Immigrants: Factors Affecting Their Perceptions Of Academic Success In A Florida Public High School, Mercedes Pichard Jan 2006

A Focus Group Of Adolescent Haitian Immigrants: Factors Affecting Their Perceptions Of Academic Success In A Florida Public High School, Mercedes Pichard

Electronic Theses and Dissertations

The goal of this ethnographic research was to examine the perceptions of academic success of adolescent Haitian immigrant students who have arrived in the United States within the last five years and attend a public high school in Florida. The Haitian students were asked to explain the tensions they perceive between Haitian societal and educational norms and beliefs and American ones, and explain their perceptions and concerns regarding success. The importance of their perceptions as influences on their behavior was related to Bandura's Social Cognitive Learning Theory. The relevance of certain questions concerning academic success for Haitian students was investigated …

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Silence, Absence, And Mystery In Linda Hogan's Mean Spirit, Solar Storms, And Power, Kathryn Erickson Jan 2006

Silence, Absence, And Mystery In Linda Hogan's Mean Spirit, Solar Storms, And Power, Kathryn Erickson

Electronic Theses and Dissertations

In Mean Spirit, Solar Storms, and Power, Linda Hogan uses the devices of silence, absence, and mystery to articulate the oppression and marginalization of Native Americans. Specifically, because of the environmental crises that produce conflict in each novel, the project benefits from ecocriticism, ecofeminism, and ecopsychology. Also, because of various interpretations that open up when silence is examined, theories of deconstruction strengthen the thesis. Ultimately, Hogan's characters move from silence as a form of tyranny to silence as a form of reconnection with tribal ways. As the characters discover pathways to native traditions, they also discover spiritual connections with the …

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The Taino Are Still Alive, Taino Cuan Yahabo: An Example Of The Social Construction Of Race And Ethnicity, David Cintron Jan 2006

The Taino Are Still Alive, Taino Cuan Yahabo: An Example Of The Social Construction Of Race And Ethnicity, David Cintron

Electronic Theses and Dissertations

Definitions and boundaries of race and ethnicity are socially constructed. They are malleable inventions created by the negotiation of ascribed ideas from outside groups and asserted notions from the inside group's membership. The revitalization of Taíno identity and culture within the Puerto Rican and related communities is a classic case example of this negotiation. Although objective conditions exist to recognize the descendants of these Caribbean aboriginals as an identifiable group, their identities are contested and sometimes ridiculed. Even though Taíno heritage is accepted as an essential root of Puerto Rico's cultural and biological make-up, this group has been classified as …

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A Fluid Structure Interaction Model Of Intracoronary Atherosclerotic Plaque Rupture, Eric Teuma-Melago Jan 2006

A Fluid Structure Interaction Model Of Intracoronary Atherosclerotic Plaque Rupture, Eric Teuma-Melago

Electronic Theses and Dissertations

Plaque rupture with superimposed thrombosis is the primary cause of acute coronary syndromes of unstable angina, myocardial infarction and sudden death. Although intensive studies in the past decade have shed light on the mechanism that causes unstable atheroma, none has directly addressed the clinical observation that most myocardial infarction (MI) patients have moderate stenoses (less than 50%). Considering the important role the arterial wall compliance and pulsitile blood flow play in atheroma rupture, fluid-structure interaction (FSI) phenomenon has been of interest in recent studies. In this thesis, the impact is investigated numerically of coupled blood flow and structural dynamics on …

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The Relationship Between Self-Reported Chronic Stress And Divided Attention Performance, Diane Petrac Jan 2006

The Relationship Between Self-Reported Chronic Stress And Divided Attention Performance, Diane Petrac

Electronic Theses and Dissertations

While previous research has extensively examined the effect of acute stress on cognitive performance, relatively little research has explored the relationship between chronic stress and cognitive performance. The current study aimed to control for current state anxiety to better isolate more chronic stress, when examining the relationship with performance on divided attention tasks. Fifty-four university undergraduates, who self-reported a wide range of perceived chronic stress (10-item Perceived Stress Scale), completed the Trail-Making Test and a dual (auditory and visual) Continuous Performance Test (CPT). Hierarchical regressions were performed to explore cognitive predictors of chronic perceived stress. After covarying for state anxiety …

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New Developments On High-Resolution Luminescence Spectroscopy And Their Application To The Direct Analysis Of Organic Pollutants, Shenjiang Yu Jan 2006

New Developments On High-Resolution Luminescence Spectroscopy And Their Application To The Direct Analysis Of Organic Pollutants, Shenjiang Yu

Electronic Theses and Dissertations

Polycyclic aromatic compounds (PACs), which comprise a complex class of condensed multi-ring benzenoid compounds, are important environmental pollutants originating from a wide variety of natural and anthropogenic sources. PACs are generally formed during incomplete combustion of pyrolisis of organic matter containing carbon and hydrogen. Because combustion of organic materials is involved in countless natural processes or human activities, PACs are omnipresent and abundant pollutants in air, soil, and water. Chemical analysis of PACs is of great environmental and toxicological importance. Many of them are highly suspect as etiological agents in human cancer. Because PACs carcinogenic properties strongly depend on molecular …

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Image-Based Material Editing, Erum Khan Jan 2006

Image-Based Material Editing, Erum Khan

Electronic Theses and Dissertations

Photo editing software allows digital images to be blurred, warped or re-colored at the touch of a button. However, it is not currently possible to change the material appearance of an object except by painstakingly painting over the appropriate pixels. Here we present a set of methods for automatically replacing one material with another, completely different material, starting with only a single high dynamic range image, and an alpha matte specifying the object. Our approach exploits the fact that human vision is surprisingly tolerant of certain (sometimes enormous) physical inaccuracies. Thus, it may be possible to produce a visually compelling …

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A Comparative Study Of Ant Colony Optimization, Matthew Becker Jan 2006

A Comparative Study Of Ant Colony Optimization, Matthew Becker

Electronic Theses and Dissertations

Ant Colony Optimization (ACO) belongs to a class of biologically-motivated approaches to computing that includes such metaheuristics as artificial neural networks, evolutionary algorithms, and artificial immune systems, among others. Emulating to varying degrees the particular biological phenomena from which their inspiration is drawn, these alternative computational systems have succeeded in finding solutions to complex problems that had heretofore eluded more traditional techniques. Often, the resulting algorithm bears little resemblance to its biological progenitor, evolving instead into a mathematical abstraction of a singularly useful quality of the phenomenon. In such cases, these abstract computational models may be termed biological metaphors. Mindful …

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E-Commerce And Caulerpa: Unregulated Dispersal Of Invasive Species, Linda J. Walters, Katherine R. Brown, Wytze T. Stam, Jeanine L. Olsen Jan 2006

E-Commerce And Caulerpa: Unregulated Dispersal Of Invasive Species, Linda J. Walters, Katherine R. Brown, Wytze T. Stam, Jeanine L. Olsen

Faculty Bibliography 2000s

Professional aquarists and hobbyists are thought to be the source of invasions of the aquarium strain of the green macroalga Caulerpa taxi folia in the Mediterranean, southern California, and Australia. The US Department of Agriculture, Animal and Plant Health Inspection Service (USDA-APHIS) restricted interstate commerce and importation of the Mediterranean clone of C taxi folia prior to the California invasion and is currently deciding if it should strengthen regulation of this genus as more species of Caulerpa are being described as invasive. Here we document the importance of e-commerce as a mode of dispersal for many species of Caulerpa in …

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Managing Fire-Prone Forests In The Western United States, Reed F. Noss, Jerry F. Franklin, William L. Baker, Tania Schoennagel, Peter B. Moyle Jan 2006

Managing Fire-Prone Forests In The Western United States, Reed F. Noss, Jerry F. Franklin, William L. Baker, Tania Schoennagel, Peter B. Moyle

Faculty Bibliography 2000s

The management of fire-prone forests is one of the most controversial natural resource issues in the US today, particularly in the west of the country. Although vegetation and wildlife in these forests are adapted to fire, the historical range of fire frequency and severity was huge. When fire regimes are altered by human activity, major effects on biodiversity and ecosystem function are unavoidable. We review the ecological science relevant to developing and implementing fire and fuel management policies for forests before, during, and after wildfires. Fire exclusion led to major deviations from historical variability in many dry, low-elevation forests, but …

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Genetically Engineered Human Mesenchymal Stem Cells Produce Met-Enkephalin At Augmented Higher Levels In Vitro, Ikuko Sugaya, Tingyu Qu, Kiminobu Sugaya, George D. Pappas Jan 2006

Genetically Engineered Human Mesenchymal Stem Cells Produce Met-Enkephalin At Augmented Higher Levels In Vitro, Ikuko Sugaya, Tingyu Qu, Kiminobu Sugaya, George D. Pappas

Faculty Bibliography 2000s

We have reported that transplantation of adrenal medullary chromaffin cells that release endogenous opioid peptides into pain modulatory regions in the CNS produce significant antinociceptive effects in patients with terminal cancer pain. However, the usefulness of this procedure is minimal because the availability of human adrenal tissue is very limited. Alternative xenogeneic materials, such as porcine and bovine adrenal chromaffin cells present problems of immune rejection and possible pathogenic contamination. In an attempt to develop opioid peptide-producing cells of autologous origin, we have transfected human mesenchymal stem cells (hMeSCs) with a mammalian expression vector containing a fusion gene of green …

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Whole-Genome Plasticity Among Mycobacterium Avium Subspecies: Insights From Comparative Genomic Hybridizations, Chia-Wei Wu, Jeremy Glasner, Michael Collins, Saleh Naser, Adel M. Talaat Jan 2006

Whole-Genome Plasticity Among Mycobacterium Avium Subspecies: Insights From Comparative Genomic Hybridizations, Chia-Wei Wu, Jeremy Glasner, Michael Collins, Saleh Naser, Adel M. Talaat

Faculty Bibliography 2000s

Infection with Mycobacterium avium subsp. paratuberculosis causes Johne's disease in cattle and is also implicated in cases of Crohn's disease in humans. Another closely related strain, M. avium subsp. avium, is a health problem for immunocompromised patients. To understand the molecular pathogenesis of M. avium subspecies, we analyzed the genome contents of isolates collected from humans and domesticated or wildlife animals. Comparative genomic hybridizations indicated distinct lineages for each subspecies where the closest genomic relatedness existed between M. avium subsp. paratuberculosis isolates collected from human and clinical cow samples. Genomic islands (n = 24) comprising 846 kb were present in …

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Collapsin Response Mediator Protein 1 Mediates Reelin Signaling In Cortical Neuronal Migration, Naoya Yamashita, Yutaka Uchida, Toshio Ohshima, Syu-Ichi Hirai, Fumio Nakamura, Masahiko Taniguchi, Katsuhiko Mikoshiba, Jerôme Honnorat, Pappachan Kolattukudy, Nicole Thomasset, Kohtaro Takei, Takuya Takahashi, Yoshio Goshima Jan 2006

Collapsin Response Mediator Protein 1 Mediates Reelin Signaling In Cortical Neuronal Migration, Naoya Yamashita, Yutaka Uchida, Toshio Ohshima, Syu-Ichi Hirai, Fumio Nakamura, Masahiko Taniguchi, Katsuhiko Mikoshiba, Jerôme Honnorat, Pappachan Kolattukudy, Nicole Thomasset, Kohtaro Takei, Takuya Takahashi, Yoshio Goshima

Faculty Bibliography 2000s

Collapsin response mediator protein 1 ( CRMP1) is one of the CRMP family members that mediates signal transduction of axon guidance molecules. Here, we show evidence that CRMP1 is involved in Reelin ( Reln) signaling to regulate neuronal migration in the cerebral cortex. In crmp1(-/-) mice, radial migration of cortical neurons was retarded. This phenotype was not observed in the sema3A(-/-) and crmp1(+/+); sema3A(+/+) cortices. However, CRMP1 was colocalized with disabled- 1 ( Dab1), an adaptor protein in Reln signaling. In the Reln(rl/rl) cortex, CRMP1 and Dab1 were expressed at a higher level, yet tyrosine phosphorylated at a lower level. …

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Biodiversity Of Sessile And Motile Macrofauna On Intertidal Oyster Reefs In Mosquito Lagoon, Florida, Michelle L. Boudreaux, Jennifer L. Stiner, Linda J. Walters Jan 2006

Biodiversity Of Sessile And Motile Macrofauna On Intertidal Oyster Reefs In Mosquito Lagoon, Florida, Michelle L. Boudreaux, Jennifer L. Stiner, Linda J. Walters

Faculty Bibliography 2000s

Our research focused on determining the diversity and abundance of sessile and motile macrofauna that use intertidal reefs of the eastern oyster Crassostrea virginica for feeding, settlement space or refuge in Mosquito Lagoon, Florida. Five replicate lift nets were deployed at six sites (three impacted reefs with seaward margins of disarticulated shells, three reference reefs Without dead margins) to determine the species composition and numbers present on these reef types. All nets were deployed intertidally on backreef areas on living oyster reefs, just above mean low water. One and a half liters of live oysters and oyster shells were placed …

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Characterization Of The Ifn-Gamma T-Cell Responses To Immediate Early Antigens In Humans With Genital Herpes, Ralph P. Braun, Lendon G. Payne, Lichun Dong Jan 2006

Characterization Of The Ifn-Gamma T-Cell Responses To Immediate Early Antigens In Humans With Genital Herpes, Ralph P. Braun, Lendon G. Payne, Lichun Dong

Faculty Bibliography 2000s

Background: The IFN-gamma ELISPOT assay has been used to examine the T-cell repertoire for many disease states in humans but, as yet, not genital herpes. Using overlapping synthetic peptide libraries, an IFN-gamma ELISPOT assay was established that could measure CD4 and CD8 T-cell responses to HSV-2 antigens in patients with genital herpes. Results: In unexpanded T-cells isolated from peripheral blood, CD4 responses were readily measured against four immediate early antigens (ICP0, ICP4, ICP22 and ICP27), VP22 and gD. The CD4 responses were characterized by a low number of positive cells which produced large ELISPOTs. CD4 responses had a broad specificity …

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Mitochondrial Uncoupling Protein-4 Regulates Calcium Homeostasis And Sensitivity To Store Depletion-Induced Apoptosis In Neural Cells, Sic. L. Chan, Dong Liu, George A. Kyriazis, Pamela Bagisyao, Xin Ouyang, Mark P. Mattson Jan 2006

Mitochondrial Uncoupling Protein-4 Regulates Calcium Homeostasis And Sensitivity To Store Depletion-Induced Apoptosis In Neural Cells, Sic. L. Chan, Dong Liu, George A. Kyriazis, Pamela Bagisyao, Xin Ouyang, Mark P. Mattson

Faculty Bibliography 2000s

An increase in the cytoplasmic-free Ca2+ concentration mediates cellular responses to environmental signals that influence a range of processes, including gene expression, motility, secretion of hormones and neurotransmitters, changes in energy metabolism, and apoptosis. Mitochondria play important roles in cellular Ca2+ homeostasis and signaling, but the roles of specific mitochondrial proteins in these processes are unknown. Uncoupling proteins (UCPs) are a family of proteins located in the inner mitochondrial membrane that can dissociate oxidative phosphorylation from respiration, thereby promoting heat production and decreasing oxyradical production. Here we show that UCP4, a neuronal UCP, influences store-operated Ca2+ entry, a process in …

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Theta-Defensins Prevent Hiv-1 Env-Mediated Fusion By Binding Gp41 And Blocking 6-Helix Bundle Formation, Stephen A. Gallo, Wei Wang, Satinder S. Rawat, Grace Jung, Alan J. Waring, Alexander M. Cole, Hong Lu, Xuxia Yan, Norelle L. Daly, David J. Craik, Shibo Jiang, Robert I. Lehrer, Robert Blumenthal Jan 2006

Theta-Defensins Prevent Hiv-1 Env-Mediated Fusion By Binding Gp41 And Blocking 6-Helix Bundle Formation, Stephen A. Gallo, Wei Wang, Satinder S. Rawat, Grace Jung, Alan J. Waring, Alexander M. Cole, Hong Lu, Xuxia Yan, Norelle L. Daly, David J. Craik, Shibo Jiang, Robert I. Lehrer, Robert Blumenthal

Faculty Bibliography 2000s

Retrocyclin-1, a 0-defensin, protects target cells from human immunodeficiency virus, type 1 (HIV-1) by preventing viral entry. To delineate its mechanism, we conducted fusion assays between susceptible target cells and effector cells that expressed HIV-1 Env. Retrocyclin-1 (4 mu M) completely blocked fusion mediated by HIV-1 Envs that used CXCR4 or CCR5 but had little effect on cell fusion mediated by HIV-2 and simian immunodeficiency virus Envs. Retrocyclin-1 inhibited HIV-1 Env-mediated fusion without impairing the lateral mobility of CD4, and it inhibited the fusion of CD4-deficient cells with cells bearing CD4-independent HIV-1 Env. Thus, it could act without cross-linking membrane …

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In Search Of Quorum Effects In Metacommunity Structure: Species Co-Occurrence Analyses, David G. Jenkins Jan 2006

In Search Of Quorum Effects In Metacommunity Structure: Species Co-Occurrence Analyses, David G. Jenkins

Faculty Bibliography 2000s

Alternative models of community assembly emphasize regional, stochastic, dispersal-based processes or local, deterministic, niche-based processes. Community ecology's historical focus on local processes implicitly assumes that local processes surpass regional processes over time or across space to derive nonrandom metacommunity structure ( i.e., a quorum effect). Quorum effects are expected late in succession among nearby sites, whereas quorum effects are not expected early in succession among distant sites. I conducted a meta-analysis of zooplankton data sets encompassing time scales of one to thousands of years and spatial scales of < 1 m to thousands of kilometers. Species co-occurrence analyses statistically evaluated presence/absence patterns relative to random patterns obtained with Monte Carlo null models. A series of weighted analyses was conducted and alternative randomization algorithms and null models were evaluated. Most zooplankton metacommunities were randomly structured in unweighted analyses, and the distribution of significant structure did not follow quorum effect predictions. Weighted analyses ( e. g., by habitat area) revealed significant, nonrandom structure in most zooplankton metacommunities, but the distribution of significant structure still did not adhere well to quorum effect predictions. Finally, additional weighting for study scale (number of sites) nullified most significant area-weighted structure, and again, the distribution of significant structure did not follow quorum effect predictions. Overall, a quorum effect was not supported, perhaps related to zooplankton life histories and energetics and/ or the quorum effect itself. Results at the presence/absence level of resolution indicated that local processes did not generally override regional processes over time or across space to drive community structure. A full integration of dispersal- and niche-based concepts in metacommunity dynamics will be most fruitful for unraveling community assembly. Species co-occurrence analyses were scale dependent ( habitat area and study size). Future analyses should use weights for important factors ( e. g., habitat area), and meta-analyses should include study scale as an additional factor contributing to apparent patterns.

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The Complete Chloroplast Genome Sequence Of Gossypium Hirsutum: Organization And Phylogenetic Relationships To Other Angiosperms, Seung-Bum Lee, Charalambos Kaittanis, Robert K. Jansen, Jessica B. Hostetler, Luke J. Tallon, Christopher D. Town, Hnery Daniell Jan 2006

The Complete Chloroplast Genome Sequence Of Gossypium Hirsutum: Organization And Phylogenetic Relationships To Other Angiosperms, Seung-Bum Lee, Charalambos Kaittanis, Robert K. Jansen, Jessica B. Hostetler, Luke J. Tallon, Christopher D. Town, Hnery Daniell

Faculty Bibliography 2000s

Background: Cotton (Gossypium hirsutum) is the most important fiber crop grown in 90 countries. In 2004-2005, US farmers planted 79% of the 5.7-million hectares of nuclear transgenic cotton. Unfortunately, genetically modified cotton has the potential to hybridize with other cultivated and wild relatives, resulting in geographical restrictions to cultivation. However, chloroplast genetic engineering offers the possibility of containment because of maternal inheritance of transgenes. The complete chloroplast genome of cotton provides essential information required for genetic engineering. In addition, the sequence data were used to assess phylogenetic relationships among the major clades of rosids using cotton and 25 other completely …

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