496 research outputs found

    Phenomenological study of special education teachers using an emergency license

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    The shortage of special education teachers is critical. One means used to increase the supply of available teachers is to issue an emergency license to teachers not fully certified in special education. This is a phenomenological study of four general education teachers practicing special education using an emergency license. Their experience is characterized around four themes--diminished control over their lives, teaching, but on the outside, supportive relationships, and becoming new and or renewed. Universal themes of lived space, lived time, and lived human relationships provide the lens through which their experiences are interpreted

    Induction of Volatile Emissions in Maize by Different Larval Instars of Spodoptera littoralis

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    Maize plants under attack by caterpillars emit a specific blend of volatiles that is highly attractive to parasitic wasps. The release of these signals is induced by elicitors in the caterpillar regurgitant. Studies suggest that plants respond differently to different herbivore species and even to different herbivore stages, thus providing parasitoids and predators with specific signals. We tested if this is the case for different larval instars of the noctuid moth Spodoptera littoralis when they feed on maize plants. Cut maize plants were incubated in diluted regurgitant from second, third, or fifth instar caterpillars. There were no differences in total amount released after these treatments, but there were small differences in the release of the minor compounds phenethyl acetate and α-humulene. Regurgitant of all three instars contained the elicitor volicitin. To test the effect of actual feeding by the larvae, potted plants were infested with caterpillars of one of the three instars, and volatiles were collected the following day. The intensity of the emissions was correlated with the number of larvae feeding on a plant, and with the amount of damage inflicted, but was independent of the instar that caused the damage. We also used artificial damage to mimic the manner of feeding of each instar to test the importance of physical aspects of damages for the odor emission. The emission was highly variable, but no differences were found among the different types of damage. In olfactometer tests, Microplitis rufiventris, a parasitoid that can only successfully parasitize second and early third instar S. littoralis, did not differentiate among the odors of maize plants attacked by different instar larvae. The odor analyses as well as the parasitoid's responses indicate that maize odors induced by S. littoralis provide parasitoids with poor information on the larval developmental stage. We discuss the results in the context of variability and lack of specificity in odorous plant signal

    The Greatest Metaphor Ever Mixed: Gold in the British Bible, 1750–1850

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    Given the frequency of negative references to gold in British allusions to filthy lucre, it emerges as an historical puzzle that Britons resorted to biblical metaphors of gold so often in describing heaven and their aspiration to be purified in God\u27s crucible. This article provides evidence for the prominence of these two metaphors in British religious and secular discourse between 1750 and 1850, and argues that Britons tried to resolve the resulting tensions by celebrating their uniquely abstract valuation of gold, in contrast to less civilized connotations of gold in Catholic and non-Christian cultures

    Teacher Retention: Retaining Teachers in High-Needs, Urban Secondary Schools in a Midwest State Post-Pandemic

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    Teacher retention has been a challenge for most schools for several years. High-needs schools have been known to have twice the trouble with teacher retention as schools not considered high-needs. The purpose of this study was to identify effective practices school principals can implement to retain teachers at high-needs, urban secondary schools. This quantitative study called on teachers from high-needs schools in Iowa to complete a survey identifying principal qualities related to retention, perceived reasons for teacher attrition, and reasons they continue to teach at their current school. Three hundred eighty-five teachers from five different Iowa school districts participated in the study. The findings of the study suggest teacher attrition and retention revolves around three main elements—Leader Member Exchange (LMX), teacher allocations, and school climate

    Effects of elevated [CO2 ] on maize defence against mycotoxigenic Fusarium verticillioides.

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    Maize is by quantity the most important C4 cereal crop; however, future climate changes are expected to increase maize susceptibility to mycotoxigenic fungal pathogens and reduce productivity. While rising atmospheric [CO2 ] is a driving force behind the warmer temperatures and drought, which aggravate fungal disease and mycotoxin accumulation, our understanding of how elevated [CO2 ] will effect maize defences against such pathogens is limited. Here we report that elevated [CO2 ] increases maize susceptibility to Fusarium verticillioides proliferation, while mycotoxin levels are unaltered. Fumonisin production is not proportional to the increase in F. verticillioides biomass, and the amount of fumonisin produced per unit pathogen is reduced at elevated [CO2 ]. Following F. verticillioides stalk inoculation, the accumulation of sugars, free fatty acids, lipoxygenase (LOX) transcripts, phytohormones and downstream phytoalexins is dampened in maize grown at elevated [CO2 ]. The attenuation of maize 13-LOXs and jasmonic acid production correlates with reduced terpenoid phytoalexins and increased susceptibility. Furthermore, the attenuated induction of 9-LOXs, which have been suggested to stimulate mycotoxin biosynthesis, is consistent with reduced fumonisin per unit fungal biomass at elevated [CO2 ]. Our findings suggest that elevated [CO2 ] will compromise maize LOX-dependent signalling, which will influence the interactions between maize and mycotoxigenic fungi
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