71 research outputs found
The Effects of Reading Fluency in the Elementary Montessori Classroom
READING FLUENCY IN ELEMENTARY Abstract The purpose of this research was to identify ways of improving reading fluency for elementary children in grades first through sixth. Children scoring below the 40th percentile on reading standardized test scores, determined our testing population. Four data collections tools were used, including a child-centered survey, a reading fluency rubric, teacher observations, and fluency graphs. The Read Naturally Program was used as the reading fluency intervention. Students made fluency progress in both the upper and lower elementary levels. This research highlights the importance of reading fluency interventions. Further research might focus on self reflection for children using the iPad Read Naturally Program
Biological detoxification of the mycotoxin deoxynivalenol and its use in genetically engineered crops and feed additives
Deoxynivalenol (DON) is the major mycotoxin produced by Fusarium fungi in grains. Food and feed contaminated with DON pose a health risk to humans and livestock. The risk can be reduced by enzymatic detoxification. Complete mineralization of DON by microbial cultures has rarely been observed and the activities turned out to be unstable. The detoxification of DON by reactions targeting its epoxide group or hydroxyl on carbon 3 is more feasible. Microbial strains that de-epoxidize DON under anaerobic conditions have been isolated from animal digestive system. Feed additives claimed to de-epoxidize trichothecenes enzymatically are on the market but their efficacy has been disputed. A new detoxification pathway leading to 3-oxo-DON and 3-epi-DON was discovered in taxonomically unrelated soil bacteria from three continents; the enzymes involved remain to be identified. Arabidopsis, tobacco, wheat, barley, and rice were engineered to acetylate DON on carbon 3. In wheat expressing DON acetylation activity, the increase in resistance against Fusarium head blight was only moderate. The Tri101 gene from Fusarium sporotrichioides was used; Fusarium graminearum enzyme which possesses higher activity towards DON would presumably be a better choice. Glycosylation of trichothecenes occurs in plants, contributing to the resistance of wheat to F. graminearum infection. Marker-assisted selection based on the trichothecene-3-O-glucosyltransferase gene can be used in breeding for resistance. Fungal acetyltransferases and plant glucosyltransferases targeting carbon 3 of trichothecenes remain promising candidates for engineering resistance against Fusarium head blight. Bacterial enzymes catalyzing oxidation, epimerization, and less likely de-epoxidation of DON may extend this list in future
Incidence of post-harvest disease and airborne fungal spores in a vegetable market
The sampling of bioaerosols has been carried out using a Rotorod sampler as well as by exposing culture plates. The screening of some common vegetables was also done for the isolation of fungi as market pathogens to study post-harvest diseases. Altogether, fifty nine fungal spore types and 78 species of 33 genera belonging to different groups were recorded respectively on the rotorod strips and on exposed Petri dishes. Many saprophytic and pathogenic fungi were found to be associated with sampled vegetables from the market. In all forty-six fungal species belonging to 26 genera were recovered from five varieties of vegetables collected from the same market. The most dominant forms of fungi were of Aspergillus followed by Cladosporium, Penicillium, Alternaria, Fusarium, Curvularia, Trichoderma, and Rhizopus. Aspergillus niger, A. flavus, A. fumigatus, Penicillium spp. and Cladosporium herbarum, found to be dominant during the period of investigation. Important mycotoxin-producing fungi such as A. flavus, A. fumigatus and Fusarium moniliforme were isolated from the vegetables collected from the market
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