48 research outputs found

    On speciation and hybridization among closely related species: establishing an experimental breeding lineage between two species of \u3ci\u3eAutomeris\u3c/i\u3e Hübner moths (Lepidoptera: Saturniidae) and implications for taxonomy

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    Many species of plants and a few species of animals are believed to have resulted from hybridization of parental species, and the ability of species to occasionally hybridize in captivity and in nature is even more widespread. In the present study, we describe a hybridization experiment conducted in the laboratory between the sexually dimorphic Automeris io (Fabricius), a widespread, variable species ranging from Canada to Costa Rica, and its congener A. louisiana (Ferguson and Brou), a more local, sexually monomorphic species (Lepidoptera: Saturniidae). The A. louisiana populations occur in a highly specialized habitat—the coastal marshland along the Gulf of Mexico in Louisiana and Texas and is nested inside the broad distribution of A. io, demonstrating strong differences from the latter in its ecology and morphology. No natural hybridization between the two species has been described. While the separate species status of A. io and A. louisiana is supported by morphology and ecology of their populations, we were able to create a hybrid lineage in the laboratory and maintained it for three generations. The hybrids were phenotypically intermediate between the parental species. Under a stricter reading of the biological species concept, such an ability to hybridize would be interpreted by some as a sign of conspecificity. Our experiments once again demonstrate the complexity of ‘species’ as a concept, which may need major redefinition in the popular interpretation of sciences

    Transcriptional regulation of FoxO3 gene by glucocorticoids in murine myotubes.

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    Glucocorticoids and FoxO3 exert similar metabolic effects in skeletal muscle. FoxO3 gene expression was increased by dexamethasone (Dex), a synthetic glucocorticoid, both in vitro and in vivo. In C2C12 myotubes the increased expression is due to, at least in part, the elevated rate of FoxO3 gene transcription. In the mouse FoxO3 gene, we identified three glucocorticoid receptor (GR) binding regions (GBRs): one being upstream of the transcription start site, -17kbGBR; and two in introns, +45kbGBR and +71kbGBR. Together, these three GBRs contain four 15-bp glucocorticoid response elements (GREs). Micrococcal nuclease (MNase) assay revealed that Dex treatment increased the sensitivity to MNase in the GRE of +45kbGBR and +71kbGBR upon 30- and 60-min Dex treatment, respectively. Conversely, Dex treatment did not affect the chromatin structure near the -17kbGBR, in which the GRE is located in the linker region. Dex treatment also increased histone H3 and/or H4 acetylation in genomic regions near all three GBRs. Moreover, using chromatin conformation capture (3C) assay, we showed that Dex treatment increased the interaction between the -17kbGBR and two genomic regions: one located around +500 bp and the other around +73 kb. Finally, the transcriptional coregulator p300 was recruited to all three GBRs upon Dex treatment. The reduction of p300 expression decreased FoxO3 gene expression and Dex-stimulated interaction between distinct genomic regions of FoxO3 gene identified by 3C. Overall, our results demonstrate that glucocorticoids activated FoxO3 gene transcription through multiple GREs by chromatin structural change and DNA looping

    Linking Science and Literacy Through Multimodal Text Sets: Student Perspectives

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    We present findings of a mixed methods study examining the perceptions of students’ (with and without disabilities) understanding and engagement with multimodal STEM text sets. Exit slip and survey data were used to identify areas for improvement in the development of the multimodal STEM text sets for middle school students. Data were collected from 434 middle school students, 86 of whom had a disability, from six teachers’ classrooms in Spring 2021. Significant differences in perceptions of understanding of argumentation were reported between students with and without disabilities. However, ratings of the lessons and the quality of learning, as well as interest in the topic, were statistically similar. Topic modeling on the responses showed that all students expressed similar learning experiences and confusions whether or not they were students with disabilities. This supports prior work which suggests that multi-modal text sets are an effective way to motivate students with a wide range of interests and abilities to engage with scientific literacy practices

    Beyond 'pivoting': Capitalising on new Knowledge and experience: in Technology and educational ‘pivoting’ in the wake of the Covid-19 pandemic: A collected commentary

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    The present document presents 13 commentaries that address the broad topic of the special issue Technology and educational 'pivoting' in the wake of the Covid-19 pandemic and, in some cases, specific articles from the issue itself. Since the launch of the journal in 2020, we have been explicit about our aspiration that Studies in Technology Enhanced Learning might serve as a vehicle for scholarly conversation (Bligh & Lee, 2020).Victoria I. Marín acknowledges grant RYC2019-028398-I funded by MCIN/AEI/ 10.13039/501100011033 and FSE “El FSE invierte en tu futuro

    On speciation and hybridization among closely related species: establishing an experimental breeding lineage between two species of \u3ci\u3eAutomeris\u3c/i\u3e Hübner moths (Lepidoptera: Saturniidae) and implications for taxonomy

    Get PDF
    Many species of plants and a few species of animals are believed to have resulted from hybridization of parental species, and the ability of species to occasionally hybridize in captivity and in nature is even more widespread. In the present study, we describe a hybridization experiment conducted in the laboratory between the sexually dimorphic Automeris io (Fabricius), a widespread, variable species ranging from Canada to Costa Rica, and its congener A. louisiana (Ferguson and Brou), a more local, sexually monomorphic species (Lepidoptera: Saturniidae). The A. louisiana populations occur in a highly specialized habitat—the coastal marshland along the Gulf of Mexico in Louisiana and Texas and is nested inside the broad distribution of A. io, demonstrating strong differences from the latter in its ecology and morphology. No natural hybridization between the two species has been described. While the separate species status of A. io and A. louisiana is supported by morphology and ecology of their populations, we were able to create a hybrid lineage in the laboratory and maintained it for three generations. The hybrids were phenotypically intermediate between the parental species. Under a stricter reading of the biological species concept, such an ability to hybridize would be interpreted by some as a sign of conspecificity. Our experiments once again demonstrate the complexity of ‘species’ as a concept, which may need major redefinition in the popular interpretation of sciences

    On speciation and hybridization among closely related species: establishing an experimental breeding lineage between two species of \u3ci\u3eAutomeris\u3c/i\u3e Hübner moths (Lepidoptera: Saturniidae) and implications for taxonomy

    No full text
    Many species of plants and a few species of animals are believed to have resulted from hybridization of parental species, and the ability of species to occasionally hybridize in captivity and in nature is even more widespread. In the present study, we describe a hybridization experiment conducted in the laboratory between the sexually dimorphic Automeris io (Fabricius), a widespread, variable species ranging from Canada to Costa Rica, and its congener A. louisiana (Ferguson and Brou), a more local, sexually monomorphic species (Lepidoptera: Saturniidae). The A. louisiana populations occur in a highly specialized habitat—the coastal marshland along the Gulf of Mexico in Louisiana and Texas and is nested inside the broad distribution of A. io, demonstrating strong differences from the latter in its ecology and morphology. No natural hybridization between the two species has been described. While the separate species status of A. io and A. louisiana is supported by morphology and ecology of their populations, we were able to create a hybrid lineage in the laboratory and maintained it for three generations. The hybrids were phenotypically intermediate between the parental species. Under a stricter reading of the biological species concept, such an ability to hybridize would be interpreted by some as a sign of conspecificity. Our experiments once again demonstrate the complexity of ‘species’ as a concept, which may need major redefinition in the popular interpretation of sciences

    Incidence, Progression, and Patterns of Multimorbidity in Community-Dwelling Middle-Aged Men and Women

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    Background: Determining the incidence, progression, and patterns of multimorbidity are important for the prevention, management, and treatment of concurrence of multiple conditions. This study aimed to analyze major multimorbidity patterns and the association of the onset of a primary condition or combinations of a primary and a secondary condition with the progression to subsequent conditions. Methods: We included 53,867 participants aged 45-64 years from the 45 and Up Study who were free of 10 predefined chronic conditions at baseline (2006-2009). The incidence of multimorbidity (coexistence of ≥2, ≥3, and ≥4 conditions) was identified using the claims database until December 31, 2016. The primary, secondary, tertiary, and quaternary condition for each participant was defined according to its temporal order of onset. Results: During a mean 9-years follow-up, the cumulative incidence of primary, secondary, tertiary, and quaternary conditions was 49.6, 23.7, 9.0, and 2.9%, respectively. The time to develop a subsequent condition decreased with the accumulation of conditions (P < 0.0001). Two concurrent cardiometabolic disorders (CMDs, 30.4%) and CMDs clustered with musculoskeletal disorders (15.2%), mental disorders (13.5%), asthma (12.0%), or cancer (8.7%) were the five most common multimorbidity patterns. CMDs tended to occur prior to mental or musculoskeletal disorders but after the onset of cancers or asthma. Compared with all participants who developed cancer as a primary condition, individuals who experienced mental disorders/neurodegenerative disorders and a comorbidity as cardiovascular disease, hypertension, dyslipidemia, diabetes, asthma, or osteoarthritis were 3.36-10.87 times more likely to develop cancer as a tertiary condition. Individuals with neurodegenerative disorders and a comorbidity as hypertension, dyslipidemia, osteoarthritis, or asthma were 5.14-14.15 times more likely to develop mental disorders as a tertiary condition. Conclusions: A high incidence of multimorbidity in middle-aged adults was observed and CMDs were most commonly seen in multimorbidity patterns. There may be accelerated aging after a primary condition occurs. Our findings also reveal a potential preventative window to obviate the development of secondary or tertiary conditions

    Iron-Catalyzed Enantioselective Multicomponent Cross-Couplings of alpha-Boryl Radicals

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    Despite recent interest in the development of iron-catalyzed transformations, methods that use iron-based catalysts capable of controlling enantioselectivity in carbon-carbon cross-couplings are underdeveloped. Herein, we report a practical and simple protocol that uses commercially available and expensive iron salts in combination with chiral bisphosphine ligands to enable thåe regio- and enantioselective (up to 91:9) multicomponent cross-coupling of vinyl boronates, (fluoro)alkyl halides, and Grignard reagents. Preliminary mechanistic studies are consistent with rapid formation of α-boryl radical followed by reversible radical addition to mono-aryl bisphosphine-Fe(II) and subsequent enantioselective inner-sphere reductive elimination. From a broader perspective, this work provides a blueprint to develop asymmetric Fe-catalyzed multicomponent cross-couplings via the use of alkenes as lynchpins to translocate alkyl radicals, modify their steric and electronic properties, and induce stereocontrol

    Fe-Catalyzed Conjunctive Cross-Couplings of Unactivated Alkenes with Grignard Reagents

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    The first iron-catalyzed three-component cross-coupling of unactivated olefins with alkyl halides and Grignard reagents is reported. The reaction operates under fast turnover frequency and tolerates a diverse range of sp2-hybridized nucleophiles, alkyl halides, and unactivated olefins bearing diverse functional groups to yield the desired 1,2-alkylarylated products with high regiocontrol. Further, we demonstrate that this protocol is amenable for the synthesis of new (hetero)carbocycles including tetrahydrofurans and pyrrolidines via a three-component radical cascade cyclization/arylation that forges three new C-C bonds

    Are Methanol-Derived Foliar Methyl Acetate Emissions a Tracer of Acetate-Mediated Drought Survival in Plants?

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    Upregulation of acetate fermentation in plants has recently been described as an evolutionarily conserved drought survival strategy, with the amount of acetate produced directly correlating to survival. However, destructive measurements are required to evaluate acetate-linked drought responses, limiting the temporal and spatial scales that can be studied. Here, 13C-labeling studies with poplar (Populus trichocarpa) branches confirmed that methyl acetate is produced in plants from the acetate-linked acetylation of methanol. Methyl acetate emissions from detached leaves were strongly stimulated during desiccation, with total emissions decreasing with the leaf developmental stage. In addition, diurnal methyl acetate emissions from whole physiologically active poplar branches increased as a function of temperature, and light-dark transitions resulted in significant emission bursts lasting several hours. During experimental drought treatments of potted poplar saplings, light-dark methyl acetate emission bursts were eliminated while strong enhancements in methyl acetate emissions lasting &gt; 6 days were observed with their initiation coinciding with the suppression of transpiration and photosynthesis. The results suggest that methyl acetate emissions represent a novel non-invasive tracer of acetate-mediated temperature and drought survival response in plants. The findings may have important implications for the future understanding of acetate-mediated drought responses to transcription, cellular metabolism, and hormone signaling, as well as its associated changes in carbon cycling and water use from individual plants to whole ecosystems
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