305 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

    Pandemic Paradox: Early Life H2N2 Pandemic Influenza Infection Enhanced Susceptibility to Death during the 2009 H1N1 Pandemic.

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    Recent outbreaks of H5, H7, and H9 influenza A viruses in humans have served as a vivid reminder of the potentially devastating effects that a novel pandemic could exert on the modern world. Those who have survived infections with influenza viruses in the past have been protected from subsequent antigenically similar pandemics through adaptive immunity. For example, during the 2009 H1N1 "swine flu" pandemic, those exposed to H1N1 viruses that circulated between 1918 and the 1940s were at a decreased risk for mortality as a result of their previous immunity. It is also generally thought that past exposures to antigenically dissimilar strains of influenza virus may also be beneficial due to cross-reactive cellular immunity. However, cohorts born during prior heterosubtypic pandemics have previously experienced elevated risk of death relative to surrounding cohorts of the same population. Indeed, individuals born during the 1890 H3Nx pandemic experienced the highest levels of excess mortality during the 1918 "Spanish flu." Applying Serfling models to monthly mortality and influenza circulation data between October 1997 and July 2014 in the United States and Mexico, we show corresponding peaks in excess mortality during the 2009 H1N1 "swine flu" pandemic and during the resurgent 2013-2014 H1N1 outbreak for those born at the time of the 1957 H2N2 "Asian flu" pandemic. We suggest that the phenomenon observed in 1918 is not unique and points to exposure to pandemic influenza early in life as a risk factor for mortality during subsequent heterosubtypic pandemics.IMPORTANCE The relatively low mortality experienced by older individuals during the 2009 H1N1 influenza virus pandemic has been well documented. However, reported situations in which previous influenza virus exposures have enhanced susceptibility are rare and poorly understood. One such instance occurred in 1918-when those born during the heterosubtypic 1890 H3Nx influenza virus pandemic experienced the highest levels of excess mortality. Here, we demonstrate that this phenomenon was not unique to the 1918 H1N1 pandemic but that it also occurred during the contemporary 2009 H1N1 pandemic and 2013-2014 H1N1-dominated season for those born during the heterosubtypic 1957 H2N2 "Asian flu" pandemic. These data highlight the heretofore underappreciated phenomenon that, in certain instances, prior exposure to pandemic influenza virus strains can enhance susceptibility during subsequent pandemics. These results have important implications for pandemic risk assessment and should inform laboratory studies aimed at uncovering the mechanism responsible for this effect

    A novel route for identifying starch diagenetic products in the archaeological record

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    This work introduces a novel analytical chemistry method potentially applicable to the study of archaeological starch residues. The investigation involved the laboratory synthesis of model Maillard reaction mixtures and their analysis through Fourier-Transform Ion Cyclotron Resonance Mass Spectrometry (FTICR-MS). Thus, starch from sixteen plant species were matured while reacting it with the amino acid glycine. The FTICR-MS analysis revealed > 5,300 molecular compounds, with numerous unique heteroatom rich compound classes, ranging from 20 (Zea mays) to 50 (Sorghum bicolor). These classes were investigated as repositories of chemical structure retaining source and process-specific character, linked back to botanical provenance. We discussed the Maillard reaction products thus generated, a possible pathway for the preservation of degraded starch, while also assessing diagenetic recalcitrance and adsorption potential to mineral surfaces. In some cases, hydrothermal experimentation on starches without glycine reveals that the chemical complexity of the starch itself is sufficient to produce some Maillard reaction products. The article concludes that FTICR-MS offers a new analytical window to characterize starchy residue and its diagenetic products, and is able to recognize taxonomic signals with the potential to persist in fossil contexts.Introduction Materials and methods - Sample preparation and characterization - FTICR-MS analysis Results - Characterization of Maillard reaction products based on atomic ratios (H/C, O/C, N/C, N/O) and compound class distribution - Variations in molecular distribution Discussion - The Maillard reaction products - Preservation pathway - Diagenetic recalcitrance of Maillard reaction products Conclusion

    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

    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

    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

    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/)
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