Pedagogy For Internet-based Teaching And Learning And The Impact Of That Pedagogy On Student Achievement And Satisfaction

The purpose of this research was to identify appropriate pedagogical practices for Internet-based teaching and learning, determine the status of their use in the community college adjunct instructor\u27s Internet-based classroom, and examine the impact of these practices on student academic achievement and satisfaction. Frequencies, measures of central tendency, percentages, and SPSS Cross Tabulation procedures described and analyzed data from student and instructor surveys to answer these questions. Internet-based best practice and recommended practice pedagogical methods and strategies were identified through extensive content analysis of the professional literature. Internet-based adjunct instructors at a Central Florida community college rated 43 selected recommended practices. Ratings were based on instructor perceptions of each practice\u27s importance to student academic achievement in and satisfaction with their Internet-based learning experience. Students of community college adjunct instructors also rated these practices for their perceived impact on student academic achievement and satisfaction. Students identified from selected recommended practices the pedagogies that had been designed into the described Internet-based course in which they had been enrolled, providing better understanding of the current use of appropriate Internet-based practice in the instruction of adjunct community college instructors. To examine the impact of the use of those practices, average course scores were related to student-reported presence of practices in described courses and student-reported academic success and satisfaction in described courses was related to the presence of best and recommended practices designed into the course. Results from this study can provide guidance for community college Internet-based programs and for adjunct instructors in those programs as they strive to design and instruct quality courses with appropriate pedagogical focus. Results can also provide local data to the larger discussion of appropriate pedagogy throughout the Internet-based educational community

Routes of freedom: slave resistance and the politics of literary geography

This dissertation integrates rhetorical, historical, and spatial analysis in an effort to expand our understanding of the cultural work performed by antebellum narratives that take slavery in the United States as their subject matter. Specifically, it focuses on the complicated relationship between place and human praxis as revealed in five texts: The Confessions of Nat Turner, Harriet Beecher Stowe’s Dred, Martin R. Delany’s Blake, Frederick Douglass’s “The Heroic Slave,” and Herman Melville’s Benito Cereno. In my attention to literary geographies, I trace spatial patterns in which considerations of organized resistance and slave rebellion are repeatedly placed in “wild-spaces” such as the Great Dismal Swamp, the Red River region of Louisiana, and the open ocean. Exploring their strict alignment with considerations of violence, I argue that these wild-spaces do not function as passive settings, supporting and paralleling narrative events or themes. Instead they can be seen to drive narrative action as they carry with them powerful cultural associations that translate into plot momentum. My methodological approach employs two general steps. First I document how antislavery writers developed a historically resonant narrative landscape to defuse criticism and buttress their rhetorical indictments of slavery. Second, I investigate how these writers negotiated the complicated demands of such landscapes in order to supplement moral interpretations with creative imaginings of how alternative forms of slave resistance might play out. By isolating the ties between literary landscapes and the narratives’ imaginings of slave resistance, we are able to see the intensely pragmatic, real world problem-solving in which these writers were engaged. Such a methodology highlights the formative function of place in literary output, while also providing insight into obstacles to real-world reform. I conclude that the narratives I examine served as a forum for cultural experimentation as their writers attempted to work through social and political problems that had no easy or ready solutions. Considerations of place are shown to be essential to antislavery writers’ attempts to see through the shadow of slavery to its end, and, in doing so, point the way forward

Meta-analysis of yield response of foliar fungicide-treated hybrid corn in the United States and Ontario, Canada

Foliar fungicide applications to corn (Zea mays L.) occur at one or more application timings ranging from early vegetative growth stages to mid-reproductive stages. Previous studies indicated that fungicide applications are profitable under high disease pressure when applied during the tasseling to silking growth stages. Few comprehensive studies in corn have examined the impact of fungicide applications at an early vegetative growth stage (V6) compared to late application timings (VT) for yield response and return on fungicide investment (ROI) across multiple locations

Meta-analysis of yield response of foliar fungicide-treated hybrid corn in the United States and Ontario, Canada

Background Foliar fungicide applications to corn (Zea mays L.) occur at one or more application timings ranging from early vegetative growth stages to mid-reproductive stages. Previous studies indicated that fungicide applications are profitable under high disease pressure when applied during the tasseling to silking growth stages. Few comprehensive studies in corn have examined the impact of fungicide applications at an early vegetative growth stage (V6) compared to late application timings (VT) for yield response and return on fungicide investment (ROI) across multiple locations. Objective Compare yield response of fungicide application timing across multiple fungicide classes and calculate the probability of positive ROI. Methods Data were collected specifically for this analysis using a uniform protocol conducted in 13 states in the United States and one province in Canada from 2014–2015. Data were subjected to a primary mixed-model analysis of variance. Subsequent univariate meta-analyses, with and without moderator variables, were performed using standard meta-analytic procedures. Follow-up power and prediction analyses were performed to aid interpretation and development of management recommendations. Results Fungicide application resulted in a range of yield responses from -2,683.0 to 3,230.9 kg/ha relative to the non-treated control, with 68.2% of these responses being positive. Evidence suggests that all three moderator variables tested (application timing, fungicide class, and disease base level), had some effect (α = 0.05) on the absolute difference in yield between fungicide treated and non-treated plots (). Application timing influenced , with V6 + VT and the VT application timings resulting in greater yield responses than the V6 application timing alone. Fungicide formulations that combined demethylation inhibitor and quinone outside inhibitor fungicides significantly increased yield response. Conclusion Foliar fungicide applications can increase corn grain yield. To ensure the likelihood of a positive ROI, farmers should focus on applications at VT and use fungicides that include a mix of demethylation inhibitor and quinone outside inhibitor active ingredients

Expression Analysis of Stress-Related Genes in Kernels of Different Maize (Zea mays L.) Inbred Lines with Different Resistance to Aflatoxin Contamination

This research examined the expression patterns of 94 stress-related genes in seven maize inbred lines with differential expressions of resistance to aflatoxin contamination. The objective was to develop a set of genes/probes associated with resistance to A. flavus and/or aflatoxin contamination. Ninety four genes were selected from previous gene expression studies with abiotic stress to test the differential expression in maize lines, A638, B73, Lo964, Lo1016, Mo17, Mp313E, and Tex6, using real-time RT-PCR. Based on the relative-expression levels, the seven maize inbred lines clustered into two different groups. One group included B73, Lo1016 and Mo17, which had higher levels of aflatoxin contamination and lower levels of overall gene expression. The second group which included Tex6, Mp313E, Lo964 and A638 had lower levels of aflatoxin contamination and higher overall levels of gene expressions. A total of six “cross-talking” genes were identified between the two groups, which are highly expressed in the resistant Group 2 but down-regulated in susceptible Group 1. When further subjected to drought stress, Tex6 expressed more genes up-regulated and B73 has fewer genes up-regulated. The transcript patterns and interactions measured in these experiments indicate that the resistant mechanism is an interconnected process involving many gene products and transcriptional regulators, as well as various host interactions with environmental factors, particularly, drought and high temperature

Responses of Aspergillus flavus to Oxidative Stress Are Related to Fungal Development Regulator, Antioxidant Enzyme, and Secondary Metabolite Biosynthetic Gene Expression

The infection of maize and peanut with Aspergillus flavus and subsequent contamination with aflatoxin pose a threat to global food safety and human health, and is exacerbated by drought stress. Drought stress-responding compounds such as reactive oxygen species (ROS) are associated with fungal stress responsive signaling and secondary metabolite production, and can stimulate the production of aflatoxin by A. flavus in vitro. These secondary metabolites have been shown to possess diverse functions in soil-borne fungi including antibiosis, competitive inhibition of other microbes, and abiotic stress alleviation. Previously, we observed that isolates of A. flavus showed differences in oxidative stress tolerance which correlated with their aflatoxin production capabilities. In order to better understand these isolate-specific oxidative stress responses, we examined the transcriptional responses of field isolates of A. flavus with varying levels of aflatoxin production (NRRL3357, AF13, and Tox4) to H2O2-induced oxidative stress using an RNA sequencing approach. These isolates were cultured in an aflatoxin-production conducive medium amended with various levels of H2O2. Whole transcriptomes were sequenced using an Illumina HiSeq platform with an average of 40.43 million filtered paired-end reads generated for each sample. The obtained transcriptomes were then used for differential expression, gene ontology, pathway, and co-expression analyses. Isolates which produced higher levels of aflatoxin tended to exhibit fewer differentially expressed genes than isolates with lower levels of production. Genes found to be differentially expressed in response to increasing oxidative stress included antioxidant enzymes, primary metabolism components, antibiosis-related genes, and secondary metabolite biosynthetic components specifically for aflatoxin, aflatrem, and kojic acid. The expression of fungal development-related genes including aminobenzoate degradation genes and conidiation regulators were found to be regulated in response to increasing stress. Aflatoxin biosynthetic genes and antioxidant enzyme genes were also found to be co-expressed and highly correlated with fungal biomass under stress. This suggests that these secondary metabolites may be produced as part of coordinated oxidative stress responses in A. flavus along with antioxidant enzyme gene expression and developmental regulation

Drought stress and aflatoxin contamination: transcriptional responses of Aspergillus flavus to oxidative stress are related to stress tolerance and aflatoxin production capability

Oilseed crops such as maize and peanut are staple food crops which are vital for global food security. The contamination of these crops with carcinogenic aflatoxins during infection by Aspergillus flavus under drought stress conditions is a serious threat to the safety of these commodities. In order to better understand the role of aflatoxin production in the biology of this pathogen under environmental stress, a collaborative transcriptome project was undertaken to examine the transcriptional responses of toxigenic and atoxigenic isolates of A. flavus to oxidative stress. Selected isolates were cultured in aflatoxin production-conducive and non-conducive media amended with varying levels of H2O2. Isolates which possessed greater tolerance to H2O2 stress and aflatoxin production capability exhibited fewer differentially expressed genes (DEGs) than those which possessed less tolerance and lower aflatoxin production. Primary metabolic mechanisms were also stimulated in response to stress along with antioxidant enzyme-encoding genes. Genes related to fungal development such as aminobenzoate degradation genes and conidiation regulators were also differentially expressed in response to stress. Secondary metabolite biosynthetic processes also formed a large component of the isolate responses to stress including those for aflatoxin, aflatrem, and kojic acid. Co-expression analyses also showed that aflatoxin biosynthetic gene expression along with antioxidant genes were highly correlated with toxigenic isolate biomass under variable stresses. These results along with others in the literature suggest that the production of these secondary metabolites may provide supplemental oxidative stress alleviation. Additional data validation using proteomics, metabolomics and whole genome resequencing (WGRS) approaches will also be discussed

A Coordinated Effort to Manage Soybean Rust in North America: A Success Story in Soybean Disease Monitoring

Existing crop monitoring programs determine the incidence and distribution of plant diseases and pathogens and assess the damage caused within a crop production region. These programs have traditionally used observed or predicted disease and pathogen data and environmental information to prescribe management practices that minimize crop loss (3,69). Monitoring programs are especially important for crops with broad geographic distribution or for diseases that can cause rapid and great economic losses. Successful monitoring programs have been developed for several plant diseases, including downy mildew of cucurbits, Fusarium head blight of wheat, potato late blight, and rusts of cereal crops (13,36,51,80)