43 research outputs found

    False stereotypes: Future teacher's expectations for their students [abstract]

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    Abstract only availablePrevious research has shown that teacher have preconceived expectations for their students. This mixed-methodological study examined how pre-service teachers expected students to perform academically based on demographic characteristics and the academic year of enrollment between sophomore and senior students. Participants (n = 354) included undergraduates enrolled in a teacher education program at a large mid-western university. Data were collected in a survey format in which participants ranked one out of twelve possible student scenarios defined by the following characteristics: gender, race, and SES. All twelve student scenarios presented a child with a stable family and involved in extracurricular activities. The participants used a scale from 1 to 5 (3 being "average" and 5 being "above average") to rank what their expectations for that particular student would be in their classroom. In addition, the participants explained their rating with a rationale. We examined the rationales for the numerical ratings provided on one question in particular within the survey, "How do you expect this student to perform academically in your classroom?" Above average ratings were further explored because the majority of both seniors and sophomores rated their scenario accordingly. (Seniors: 72.5%; Sophomores: 76.8%) Qualitative responses into the following categories: race, SES, family stability, and extracurricular involvement were tallied and analyzed. Overall, extracurricular involvement and/or family stability were viewed as indicators for above average academic performance. No significant differences were found between the sophomore and senior responses. Across scenarios the most stated reasons for above average academic performance were family stability and/or extracurricular involvement. No differences were found between race, gender, or SES. These findings suggest that many pre-service teachers, regardless of class rank, hold assumptions that a "stable" family and extracurricular involvement plays a significant role in their student's academic performance. Further implications for teacher preparation programs are discussed.College of Educatio

    Acaulospora flavopapillosa, a new fungus in the Glomeromycetes from a coffee plantation in Peru, with an updated key for the identification of Acaulosporaceae species

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    A new fungus of the arbuscular-mycorrhiza forming Glomeromycetes was found in a coffee plantation in Palestina, located in the Amazonian region of San Martín State in Peru. The fungus was propagated in bait cultures on Brachiaria brizantha, Medicago sativa and Sorghum vulgare as host plants. It forms typical acaulosporoid spores laterally on sporiferous saccule necks. The spores are brownish yellow to yellow brown, 125-160 μm in diam and are crowded with papillae on their surface. The papillae are approximately 1 μm wide as well as high. According to the color and surface structure of its spores, the fungus is here described under the epithet Acaulospora flavopapillosa. Phylogenetically, the new fungus clusters in a well-separated clade within a group that comprises A. fragilissima, A. saccata, A. papillosa, A. morrowiae, A. delicata, A. rugosa, A. dilatata and A. longula. Also A. excavata and A. dilatata were found by concomitant morphological and molecular phylogenetic analyses in San Martín State during this study: A. excavata in another coffee plantation, and A. dilatata in an inka nut plantation. An identification key for all species in the family Acaulosporaceae is updated in this study

    Acaulospora flava, a new arbuscular mycorrhizal fungus from Coffea arabica and Plukenetia volubilis plantations at the sources of the Amazon river in Peru

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    A new arbuscular mycorrhizal fungus, Acaulospora flava, was found in coffee (Coffea arabica) and inka nut (Plukenetia volubilis) plantations in the Amazonia region of San Martín State in Peru. The fungus was propagated in bait cultures on Sorghum vulgare, Brachiaria brizantha and Medicago sativa as host plants. It differentiates typical acaulosporoid spores laterally on sporiferous saccule necks. The spores are light yellow, bright yellow to yellow brown, (95-)105-160 × (95-)100-150 μm in diameter and have smooth spore surfaces. Phylogenetically, A. flava clusters in a well-separated clade, nearest to A. kentinensis, followed by A. herrerae, A. spinosissima, A. excavata and A. aspera, of which remarkably A. spinosissima, A. excavata and A. aspera had also been found in inka nut plantations of San Martín State during the last years. Here, we report also A. herrerae and A. fragilissima as fungal symbionts within the rhizosphere of coffee and the inka nut. The later two fungi had so far been recorded by concomitant morphological and molecular analyses only from tropical islands, A. herrerae from Cuba in the Golf of Mexico and A. fragilissima from New Caledonia in the southwest Pacific Ocean close to Australia. In this study, the ITS region of A. herrerae was analyzed for the first time and deposited in the public databases. In total, we already recovered fourteen Acaulospora species from coffee and inka nut plantations in San Martín State of Peru, suggesting that Acaulospora species are frequent and beneficial symbionts in coffee and inka nut roots in San Martín State of Peru

    Paraglomus pernambucanum sp. nov. and Paraglomus bolivianum comb. nov., and biogeographic distribution of Paraglomus and Pacispora

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    Paraglomus pernambucanum sp. nov. (Paraglomeromycetes) was found in a tropical dry forest in the semi-arid Caatinga biome of Pernambuco State (NE Brazil), in a cowpea and in two maize production sites. It was characterized by combined morphological and molecular analyses on the spores isolated from field soil samples. Another species, Pacispora boliviana (Glomeromycetes), first described only by spore morphology, had been known from another semi-arid biome in Southern America, the Gran Chaco in Bolivia. We detected this fungus now also at different locations in semi-arid to semi-humid NE Brazil. As for P. pernambucanum phylogenetic analyses were performed on nuclear ribosomal RNA gene sequences of the LSU region. For P. boliviana, the spores for these analyses originated from a trap culture inoculated with soils from the type location. The results now revealed that also P. boliviana belongs to Paraglomus. It grouped in a separate monophyletic cluster adjacent to P. pernambucanum, to P. brasilianum, P. laccatum and the type species P. occultum. Thus, P. boliviana is transferred to Paraglomus, as Paraglomus bolivianum comb. nov. Remarkably, it is the first species known in the Paraglomeromycetes with pigmented spores. Paraglomus pernambucanum and P. bolivianum have several features in common: e.g. bi-walled spores, and densely pitted surface ornamentations on the structural layer of the outer wall. Spores of the two species can be distinguished by color and the diagnostic nature of their pitted ornamentation. The current knowledge about the global distribution of Paraglomus and Pacispora species is summarized and discussed

    EXD2 governs germ stem cell homeostasis and lifespan by promoting mitoribosome integrity and translation

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    Mitochondria are subcellular organelles critical for meeting the bioenergetic and biosynthetic needs of the cell. Mitochondrial function relies on genes and RNA species encoded both in the nucleus and mitochondria, as well as their coordinated translation, import and respiratory complex assembly. Here we describe the characterization of exonuclease domain like 2 (EXD2), a nuclear encoded gene that we show is targeted to the mitochondria and prevents the aberrant association of mRNAs with the mitochondrial ribosome. The loss of EXD2 resulted in defective mitochondrial translation, impaired respiration, reduced ATP production, increased reactive oxygen species and widespread metabolic abnormalities. Depletion of EXD2/CG6744 in D.melanogaster caused developmental delays and premature female germline stem cell attrition, reduced fecundity and a dramatic extension of lifespan that could be reversed with an anti-oxidant diet. Our results define a conserved role for EXD2 in mitochondrial translation that influences development and aging

    Maternal variants in NLRP and other maternal effect proteins are associated with multilocus imprinting disturbance in offspring

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    Background: Genomic imprinting results from the resistance of germline epigenetic marks to reprogramming in the early embryo for a small number of mammalian genes. Genetic, epigenetic or environmental insults that prevent imprints from evading reprogramming may result in imprinting disorders, which impact growth, development, behaviour and metabolism. We aimed to identify genetic defects causing imprinting disorders, by whole-exome sequencing in families with one or more members affected by multi-locus imprinting disturbance. Methods: Whole-exome sequencing was performed in 38 pedigrees where probands had multi-locus imprinting disturbance, in five of whom, maternal variants in NLRP5 have previously been found. Results: We now report 15 further pedigrees in which offspring had disturbance of imprinting, while their mothers had rare, predicted-deleterious variants in maternal-effect genes, including NLRP2, NLRP7 and PADI6. As well as clinical features of well-recognised imprinting disorders, some offspring had additional features including developmental delay, behavioural problems and discordant monozygotic twinning, while some mothers had reproductive problems including pregnancy loss. Conclusion: The identification of 20 putative maternal-effect variants in 38 families affected by multi-locus imprinting disorders adds to the evidence that maternal genetic factors affect oocyte fitness and thus offspring development. Testing for maternal-effect genetic variants should be considered in families affected by atypical imprinting disorders.<br/

    Fungal Systematics and Evolution: FUSE 8

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    In this 8th contribution to the Fungal Systematics and Evolution series published by Sydowia, the authors formally describe 11 species: Cortinarius caryae, C. flavolilacinus, C. lilaceolamellatus, C. malodorus, C. olivaceolamellatus, C. quercophilus, C. violaceoflavescens, C. viridicarneus, Entoloma meridionale (Agaricales), Hortiboletus rupicapreus (Boletales), and Paraglomus peruvianum (Paraglomerales). The following new country records are reported: Bolbitius callistus (Agaricales) from Russia and Hymenoscyphus equiseti (Helotiales) from Sweden. Hymenoscyphus equiseti is proposed as a new combination for Lanzia equiseti, based on ITS and LSU sequence data in combination with morphological study

    Reflecting the automated vehicle’s perception and intention: Light-based interaction approaches for on-board HMI in highly automated vehicles

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    The number of automated driving functionalities in conventional vehicles is rising year by year. Intensive research regarding highly automated vehicles (AV) is performed by all big OEMs. AVs need advanced sensors and intelligence to detect relevant objects in driving situations and to perform driving tasks safely. Due to the shift of control, the role of the driver changes to an on-board user without any driving related tasks. However, the interaction between the AV and its on-board user stays vital in terms of creating a common understanding of the current situation and establishing a shared representation of the upcoming manoeuvre to ensure user acceptance and trust in automation. The current paper investigates two different light-based HMI approaches for AV / on-board user interaction. In a VR-Study 33 participants experienced an automated left turn in an urban scenario in highly automated driving. While turning, the AV had to consider other road users (pedestrian or another vehicle). The two HMI approaches (intention- vs. perception-based) were compared to a baseline using a within-subject design. Results reveal that using perception- or intention-based interaction design lead to higher user trust and usability in both scenarios
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