270 research outputs found

    Photometric and proper motion study of neglected open cluster NGC 2215

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    Optical UBVRI photometric measurements using the Faulkes Telescope North were taken in early 2011 and combined with 2MASS JHKs_s and WISE infrared photometry as well as UCAC4 proper motion data in order to estimate the main parameters of the galactic open cluster NGC 2215 of which large uncertainty exists in the current literature. Fitting a King model we estimate a core radius of 1.12±'\pm0.04' (0.24±\pm0.01pc) and a limiting radius of 4.3±4.3'\pm0.5' (0.94±\pm0.11pc) for the cluster. The results of isochrone fits indicates an age of log(t)=8.85±0.10log(t)=8.85\pm0.10 with a distance of d=790±90d=790\pm90pc, a metallicity of [Fe/H]=0.40±0.10[Fe/H]=-0.40\pm0.10 dex and a reddening of E(BV)=0.26±0.04E(B-V)=0.26\pm0.04. A proportion of the work in this study was undertaken by Australian and Canadian upper secondary school students involved in the Space to Grow astronomy education project, and is the first scientific publication to have utilized our star cluster photometry curriculum materials.Comment: 10 pages, 9 Figures, 3 Table

    The \u3cem\u3eChlamydomonas\u3c/em\u3e Genome Reveals the Evolution of Key Animal and Plant Functions

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    Chlamydomonas reinhardtii is a unicellular green alga whose lineage diverged from land plants over 1 billion years ago. It is a model system for studying chloroplast-based photosynthesis, as well as the structure, assembly, and function of eukaryotic flagella (cilia), which were inherited from the common ancestor of plants and animals, but lost in land plants. We sequenced the ∼120-megabase nuclear genome of Chlamydomonas and performed comparative phylogenomic analyses, identifying genes encoding uncharacterized proteins that are likely associated with the function and biogenesis of chloroplasts or eukaryotic flagella. Analyses of the Chlamydomonas genome advance our understanding of the ancestral eukaryotic cell, reveal previously unknown genes associated with photosynthetic and flagellar functions, and establish links between ciliopathy and the composition and function of flagella

    Slow violence and toxic geographies : ‘out of sight’ to whom?

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    Toxic pollution is a form of violence. This article explores the gradual brutalities that communities surrounded by petrochemical infrastructure endure over time. Contributing to political geographies of violence and environmental justice, this paper puts the concept of ‘slow violence’ into critical comparison with work on ‘structural violence’. In doing so, the paper makes two key contributions: First, it emphasizes the intimate connections between structural and slow forms of harm, arguing that structural inequality can mutate into noxious instances of slow violence. Second, the paper pushes back against framings of toxic landscapes as entirely invisible to the people they impact. Instead of accepting the standard definition of slow violence as ‘out of sight’, we have to instead ask the question: ‘out of sight to whom?’ In asking this question, and taking seriously the knowledge claims of communities who inhabit toxic spaces, we can begin to unravel the political structures that sustain the uneven geographies of pollution. Based on long-term ethnographic research in a postcolonial region of Louisiana, nicknamed ‘Cancer Alley’, this paper reveals how people gradually ‘witness’ the impacts of slow violence in their everyday lives. Finally, drawing on the notion of ‘epistemic violence’, the paper suggests that slow violence does not persist due to a lack of arresting stories about pollution, but because these stories do not count, thus rendering certain populations and geographies vulnerable to sacrifice

    ARTIST???S CREATIVE CONTRIBUTIONS IN THE CONTEXT OF INTERDISCIPLINARY RESEARCH

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    While expectations regarding art???s potential contributions to the interdisciplinary research context continue to grow, the creative endeavors of individual artists remain under-examined, perhaps because of the inter-relational nature of joint research settings. To explore, how artists navigate their contribution to a given research community, this study reviews the art practice of Seung-Hyun Ko, who participated in Science Walden, a Convergent Research Center carrying out an interdis-ciplinary research project that aimed to build an ecologically sustainable community. Drawing on comprehensive views of creativity that emphasize the importance of the social context in which the efforts of individuals emerge and are assessed, the study examines Ko???s recent collaborative practice in Science Walden within the larger context of his long-term practice as a leading artist of Yatoo, a bioregionally conscious artist community. Ko???s responses to the opportunities and challenges of his involvement in these two interrelated contexts disclose the value of the creative dynamics of interdisciplinary research, with implications for the increasingly diverse interdisciplinary research practices emerging within science and technology

    Back the bid: the 2012 summer games and the governance of London

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    The Olympic Park being developed in east London for the 2012 Games is one large urban renewal project among many in the city. The impact of the Games on urban development may be of less significance than the impact on city politics. Bidding for and delivering the Games has contributed to a reassessment of the recent experiment with mayoral government. The paper examines these changing representations of the structures of London government that are now seen as a success. Much of the literature on Olympic cities is highly critical of the impact of the games, but the (current) substantial support for London2012 also needs to be explained. We examine how London has created opportunities for support, and moments and spaces for celebration when political leaders and Londoners can come together around particular representations of themselves and the city

    Using Genomic Sequencing for Classical Genetics in E. coli K12

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    We here develop computational methods to facilitate use of 454 whole genome shotgun sequencing to identify mutations in Escherichia coli K12. We had Roche sequence eight related strains derived as spontaneous mutants in a background without a whole genome sequence. They provided difference tables based on assembling each genome to reference strain E. coli MG1655 (NC_000913). Due to the evolutionary distance to MG1655, these contained a large number of both false negatives and positives. By manual analysis of the dataset, we detected all the known mutations (24 at nine locations) and identified and genetically confirmed new mutations necessary and sufficient for the phenotypes we had selected in four strains. We then had Roche assemble contigs de novo, which we further assembled to full-length pseudomolecules based on synteny with MG1655. This hybrid method facilitated detection of insertion mutations and allowed annotation from MG1655. After removing one genome with less than the optimal 20- to 30-fold sequence coverage, we identified 544 putative polymorphisms that included all of the known and selected mutations apart from insertions. Finally, we detected seven new mutations in a total of only 41 candidates by comparing single genomes to composite data for the remaining six and using a ranking system to penalize homopolymer sequencing and misassembly errors. An additional benefit of the analysis is a table of differences between MG1655 and a physiologically robust E. coli wild-type strain NCM3722. Both projects were greatly facilitated by use of comparative genomics tools in the CoGe software package (http://genomevolution.org/)

    Meta-analysis of bone mineral density in adults with phenylketonuria

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    © 2024. The Author(s).BACKGROUND: Lifelong management of phenylketonuria (PKU) centers on medical nutrition therapy, including dietary phenylalanine (Phe) restriction in addition to Phe-free or low-Phe medical foods/protein substitutes. Studies have reported low bone mineral density (BMD) in mixed-age PKU populations, possibly related to long-term Phe restriction. Therefore, a meta-analysis investigating BMD specifically in adults with PKU was conducted. METHODS: Studies reporting BMD-related outcomes were identified from a systematic literature review evaluating somatic comorbidities experienced by adults with PKU on a Phe-restricted diet (searched February 1, 2022, updated November 1, 2023). Risk of study bias was assessed (Scottish Intercollegiate Guidelines Network checklists). The primary outcome of the meta-analysis was pooled mean BMD Z-scores of different bones. Secondary outcomes were the prevalence of low BMD Z-scores at pre-specified thresholds. Subgroup analyses of mean BMD Z-scores (decade of study publication, controlled versus uncontrolled blood Phe levels, gender) were conducted. RESULTS: BMD-related data from 4097 individuals across 10 studies rated as at least acceptable quality were included. Mean BMD Z-scores were statistically significantly lower compared with an age-matched control or reference (non-PKU) population, across bones, but still within the expected range for age (> -2.0): lumbar spine (seven studies, n = 304), -0.63 (95% confidence interval (CI): -0.74, -0.52); femoral neck (four studies, n = 170), -0.74 (95% CI: -1.25, -0.22); radius (three studies, n = 114), -0.77 (95% CI: -1.21, -0.32); total body (four studies, n = 157), -0.61 (95% CI: -0.77, -0.45). The small number of observations in the subgroup analyses resulted in a high degree of uncertainty, limiting interpretation. Estimated prevalence of BMD Z-scores ≤ -2.0 was 8% (95% CI: 5%, 13%; four studies, n = 221) and < -1.0 was 42% (95% CI: 35%, 51%; five studies, n = 144). CONCLUSIONS: Adults with PKU had lower BMD Z-scores than the reference (non-PKU) population but < 1 in 10 were below the expected range for age. The low number of studies prevents identification of which population characteristics are most impacting BMD. This meta-analysis was supported by BioMarin Pharmaceutical Inc., Novato, CA and is registered with the Research Registry (reviewregistry1476).publishersversionpublishe

    Kinds of well-being: A conceptual framework that provides direction for caring

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    This article offers a conceptual framework by which different kinds and levels of well-being can be named, and as such, provides a foundation for a resource-oriented approach in situations of illness and vulnerability (rather than a deficit-oriented approach). Building on a previous paper that articulated the philosophical foundations of an existential theory of well-being (“Dwelling-mobility”), we show here how the theory can be further developed towards practice-relevant concerns. We introduce 18 kinds of well-being that are intertwined and inter-related, and consider how each emphasis can lead to the formulation of resources that have the potential to give rise to well-being as a felt experience. By focusing on a much wider range of well-being possibilities, practitioners may find new directions for care that are not just literal but also at an existential level

    Earliest Olduvai hominins exploited unstable environments ~ 2 million years ago

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    Rapid environmental change is a catalyst for human evolution, driving dietary innovations, habitat diversification, and dispersal. However, there is a dearth of information to assess hominin adaptions to changing physiography during key evolutionary stages such as the early Pleistocene. Here we report a multiproxy dataset from Ewass Oldupa, in the Western Plio-Pleistocene rift basin of Olduvai Gorge (now Oldupai), Tanzania, to address this lacuna and offer an ecological perspective on human adaptability two million years ago. Oldupai’s earliest hominins sequentially inhabited the floodplains of sinuous channels, then river-influenced contexts, which now comprises the oldest palaeolake setting documented regionally. Early Oldowan tools reveal a homogenous technology to utilise diverse, rapidly changing environments that ranged from fern meadows to woodland mosaics, naturally burned landscapes, to lakeside woodland/palm groves as well as hyper-xeric steppes. Hominins periodically used emerging landscapes and disturbance biomes multiple times over 235,000 years, thus predating by more than 180,000 years the earliest known hominins and Oldowan industries from the Eastern side of the basin.Introduction Results - Stratigraphy and archaeology - Early Oldowan ecology at ~ 2 Ma Discussion Methods - Biomarkers - Energy dispersive X-ray fluorescence - Excavation - Fauna - Mineral geochemistry - Phytolith analysis - Pollen and microcharcoal - Stable carbon and oxygen isotope analysis of faunal dental enamel - Stone tool

    Genetic diversity in invasive populations of Argentine stem weevil associated with adaptation to biocontrol

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    Modified, agricultural landscapes are susceptible to damage by insect pests. Biological control of pests is typically successful once a control agent has established, but this depends on the agent’s capacity to co-evolve with the host. Theoretical studies have shown that different levels of genetic variation between the host and the control agent will lead to rapid evolution of resistance in the host. Although this has been reported in one instance, the underlying genetics have not been studied. To address this, we measured the genetic variation in New Zealand populations of the pasture pest, Argentine stem weevil (Listronotus bonariensis), which is controlled with declining effectiveness by a parasitoid wasp, Microctonus hyperodae. We constructed a draft reference genome of the weevil, collected samples from a geographical survey of 10 sites around New Zealand, and genotyped them using a modified genotyping-by-sequencing approach. New Zealand populations of Argentine stem weevil have high levels of heterozygosity and low population structure, consistent with a large effective population size and frequent gene flow. This implies that Argentine stem weevils were able to evolve more rapidly than their biocontrol agent, which reproduces asexually. These findings show that monitoring genetic diversity in biocontrol agents and their targets is critical for long-term success of biological control
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