664 research outputs found

    Microbial players and processes involved in phytoplankton bloom utilization in the water column of a fast-flowing, river-dominated estuary

    Get PDF
    © The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in MicrobiologyOpen 6 (2017): e467, doi:10.1002/mbo3.467.Fueled by seasonal phytoplankton blooms, the Columbia River estuary is a natural bioreactor for organic matter transformations. Prior metagenome analyses indicated high abundances of diverse Bacteroidetes taxa in estuarine samples containing phytoplankton. To examine the hypothesis that Bacteroidetes taxa have important roles in phytoplankton turnover, we further analyzed metagenomes from water collected along a salinity gradient at 0, 5, 15, 25, and 33 PSU during bloom events. Size fractions were obtained by using a 3-μm prefilter and 0.2-μm collection filter. Although this approach targeted bacteria by removing comparatively large eukaryotic cells, the metagenome from the ES-5 sample (5 PSU) nevertheless contained an abundance of diatom DNA. Biogeochemical measurements and prior studies indicated that this finding resulted from the leakage of cellular material due to freshwater diatom lysis at low salinity. Relative to the other metagenomes, the bacterial fraction of ES-5 was dramatically depleted of genes annotated as Bacteroidetes and lysogenic bacteriophages, but was overrepresented in DNA of protists and Myxococcales bacterivores. We suggest the following equally plausible scenarios for the microbial response to phytoplankton lysis: (1) Bacteroidetes depletion in the free-living fraction may at least in part be caused by their attachment to fluvial diatoms as the latter are lysed upon contact with low-salinity estuarine waters; (2) diatom particle colonization is likely followed by rapid bacterial growth and lytic phage infection, resulting in depletion of lysogenic bacteriophages and host bacteria; and (3) the subsequent availability of labile organic matter attracted both grazers and predators to feed in this estuarine biogeochemical “hotspot,” which may have additionally depleted Bacteroidetes populations. These results represent the first detailed molecular analysis of the microbial response to phytoplankton lysis at the freshwater–brackish water interface in the fast-flowing Columbia River estuary.National Science Foundation Grant Numbers: OCE 0424602, MCB 064446

    Metal Decorated Multi-Walled Carbon Nanotube/Polyimide Composites with High Dielectric Constants and Low Loss Factors

    Get PDF
    The measurement of observable electromagnetic phenomena in materials and their derived intrinsic electrical material properties are of prime importance in the discovery and development of material systems for electronic and aerospace applications. Nanocomposite materials comprised of metal decorated multi-walled carbon nanotubes (MWCNTs) were prepared by a facile method and characterized. Metal particles such as silver(Ag), platinum(Pt) and palladium(Pd) with diameters ranging from less than 5 to over 50 nanometers were distributed randomly on the MWCNTs. The present study is focused on silver decorated MWCNTs dispersed in a polyimide matrix. The Ag-containing MWCNTs were melt mixed into Ultem(TradeMark) and the mixture extruded as ribbons. The extruded ribbons exhibited a moderate to high degree of MWCNT alignment as determined by HRSEM. These ribbons were then fabricated into test specimens while maintaining MWCNT alignment and subsequently characterized for electrical and electromagnetic properties at 8-12 GHz. The results of the electromagnetic characterization showed that certain sample configurations exhibited a decoupling of the permittivity (epsilon ) and loss factor (epsilon") indicating that these properties could be tailored within certain limits. The decoupling and independent control of these fundamental electrical material parameters offers a new class of materials with potential applications in electronics, microwave engineering and optics

    Cancer-related Disparities among Residents of Appalachia Ohio

    Full text link
    The authors sought to identify cancer-related disparities in Appalachia Ohio and better understand reasons for the disparities. Data from the Ohio Cancer Incidence Surveillance System, among other sources, were used to examine potential cancer disparities among residents of Appalachia Ohio. Using Ohio census data, the authors examined contributions of household income, educational attainment and population density to disparities in cancer incidence. Results suggest the following disparities in Appalachia Ohio (compared to non-Appalachia Ohio): greater cancer incidence and mortality rates for cancers of the cervix, colon and rectum, lung and bronchus and melanoma of the skin; a later stage at diagnosis of melanoma of the skin; lower prevalence of cancer screening behaviors of mammography, Pap smears, and sigmoidoscopy/colonoscopy; and less favorable cancer-related behaviors of obesity, physical activity, diet and especially tobacco smoking. Disparities in Appalachia Ohio may be associated with differences in household income, educational attainment and population density

    KRAP tethers IP3 receptors to actin and licenses them to evoke cytosolic Ca2+ signals

    Get PDF
    Regulation of IP3 receptors (IP3Rs) by IP3 and Ca2+ allows regenerative Ca2+ signals, the smallest being Ca2+ puffs, which arise from coordinated openings of a few clustered IP3Rs. Cells express thousands of mostly mobile IP3Rs, yet Ca2+ puffs occur at a few immobile IP3R clusters. By imaging cells with endogenous IP3Rs tagged with EGFP, we show that KRas-induced actin-interacting protein (KRAP) tethers IP3Rs to actin beneath the plasma membrane. Loss of KRAP abolishes Ca2+ puffs and the global increases in cytosolic Ca2+ concentration evoked by more intense stimulation. Over-expressing KRAP immobilizes additional IP3R clusters and results in more Ca2+ puffs and larger global Ca2+ signals. Endogenous KRAP determines which IP3Rs will respond: it tethers IP3R clusters to actin alongside sites where store-operated Ca2+ entry occurs, licenses IP3Rs to evoke Ca2+ puffs and global cytosolic Ca2+ signals, implicates the actin cytoskeleton in IP3R regulation and may allow local activation of Ca2+ entry. 2021, The Author(s).The authors thank Martyn Reynolds and Stephen Tovey (Cairn, UK) for help with super-resolution confocal microscopy. Supported by a Wellcome Senior Investigator Award (grant no. 101844), and by a grant (grant no. BB/T012986/1) and studentship (to H.A.S) from the Biotechnology and Biological Sciences Research Council UK. P.A.-A. is a research fellow of Emmanuel College, Cambridge.Scopu

    Antenna with Dielectric Having Geometric Patterns

    Get PDF
    An antenna includes a ground plane, a dielectric disposed on the ground plane, and an electrically-conductive radiator disposed on the dielectric. The dielectric includes at least one layer of a first dielectric material and a second dielectric material that collectively define a dielectric geometric pattern, which may comprise a fractal geometry. The radiator defines a radiator geometric pattern, and the dielectric geometric pattern is geometrically identical, or substantially geometrically identical, to the radiator geometric pattern

    Human aging is characterized by focused changes in gene expression and deregulation of alternative splicing

    Get PDF
    This is the final version. Available on open access from Wiley via the DOI in this recordSummary: Aging is a major risk factor for chronic disease in the human population, but there are little human data on gene expression alterations that accompany the process. We examined human peripheral blood leukocyte in-vivo RNA in a large-scale transcriptomic microarray study (subjects aged 30-104years). We tested associations between probe expression intensity and advancing age (adjusting for confounding factors), initially in a discovery set (n=458), following-up findings in a replication set (n=240). We confirmed expression of key results by real-time PCR. Of 16571 expressed probes, only 295 (2%) were robustly associated with age. Just six probes were required for a highly efficient model for distinguishing between young and old (area under the curve in replication set; 95%). The focused nature of age-related gene expression may therefore provide potential biomarkers of aging. Similarly, only 7 of 1065 biological or metabolic pathways were age-associated, in gene set enrichment analysis, notably including the processing of messenger RNAs (mRNAs); [P<0.002, false discovery rate (FDR) q<0.05]. This is supported by our observation of age-associated disruption to the balance of alternatively expressed isoforms for selected genes, suggesting that modification of mRNA processing may be a feature of human aging. © 2011 The Authors. Aging Cell © 2011 Blackwell Publishing Ltd/Anatomical Society of Great Britain and Ireland.National Institute for Health Research (NIHR

    Early observed transient prostate-specific antigen elevations on a pilot study of external beam radiation therapy and fractionated MRI guided High Dose Rate brachytherapy boost

    Get PDF
    PURPOSE: To report early observation of transient PSA elevations on this pilot study of external beam radiation therapy and magnetic resonance imaging (MRI) guided high dose rate (HDR) brachytherapy boost. MATERIALS AND METHODS: Eleven patients with intermediate-risk and high-risk localized prostate cancer received MRI guided HDR brachytherapy (10.5 Gy each fraction) before and after a course of external beam radiotherapy (46 Gy). Two patients continued on hormones during follow-up and were censored for this analysis. Four patients discontinued hormone therapy after RT. Five patients did not receive hormones. PSA bounce is defined as a rise in PSA values with a subsequent fall below the nadir value or to below 20% of the maximum PSA level. Six previously published definitions of biochemical failure to distinguish true failure from were tested: definition 1, rise >0.2 ng/mL; definition 2, rise >0.4 ng/mL; definition 3, rise >35% of previous value; definition 4, ASTRO defined guidelines, definition 5 nadir + 2 ng/ml, and definition 6, nadir + 3 ng/ml. RESULTS: Median follow-up was 24 months (range 18–36 mo). During follow-up, the incidence of transient PSA elevation was: 55% for definition 1, 44% for definition 2, 55% for definition 3, 33% for definition 4, 11% for definition 5, and 11% for definition 6. CONCLUSION: We observed a substantial incidence of transient elevations in PSA following combined external beam radiation and HDR brachytherapy for prostate cancer. Such elevations seem to be self-limited and should not trigger initiation of salvage therapies. No definition of failure was completely predictive

    Manual / Issue 13 / Storage

    Get PDF
    Manual, a journal about art and its making. Storage. Manual 13 opens with an introduction by Fred Wilson, who confides, “You can look at all the opulence on display in a museum and begin to understand that something nefarious might be behind it. Storage, for me, is where the action is.” Museums usually make choices for viewers, their curators presenting what they think most important within a category. They can be so good at doing this that visitors sometimes don’t realize there’s anything else to see: they don’t realize the nature of the decisions behind an exhibition, and they accept that the elites have made a judgment about which shoe is the shoe to see. Visitors can learn about what’s great, but they don’t necessarily consider the process of discernment. –– Fred Wilson The RISD Museum’s thirteenth issue of Manual unpacks the idea and reality of storage—objects museums don’t put on view, works made as containers of various sorts, and more metaphorical considerations about how meanings and narratives are stored. This issue serves as a companion to the Raid the Icebox Now series of exhibitions on view at the RISD Museum through November 2020, in which nine contemporary artists and design collectives use the museum and its collections as a site for critical creative production and presentation. Raid the Icebox Now marks the 50th anniversary of Raid the Icebox 1 with Andy Warhol, held in 1970 at the RISD Museum. Softcover, 120 pages. Published Fall/Winter 2019 by the RISD Museum. Manual 13 (Storage) contributors include: Christina Alderman, Issac M. Alderman, A.H. Jerriod Avant, Hannah Carlson, Wai Yee Chiong, John Dunnigan, Maria Morris Hambourg, David Hartt, Elaine Tyler May, Claire McCardell, Denise Murrell, Ingrid Schaffner, Holly Shaffer, Tanya Sheehan, John W. Smith, Mimi Smith, Sassan Tabatabai, Allen Wexler, and Fred Wilson.https://digitalcommons.risd.edu/risdmuseum_journals/1039/thumbnail.jp
    • …
    corecore