298 research outputs found

    Intrinsic antimicrobial resistance determinants in the superbug Pseudomonas aeruginosa

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    Antimicrobial-resistant bacteria pose a serious threat in the clinic. This is particularly true for opportunistic pathogens that possess high intrinsic resistance. Though many studies have focused on understanding the acquisition of bacterial resistance upon exposure to antimicrobials, the mechanisms controlling intrinsic resistance are not well understood. In this study, we subjected the model opportunistic superbug Pseudomonas aeruginosa to 14 antimicrobials under highly controlled conditions and assessed its response using expression-and fitness-based genomic approaches. Our results reveal that gene expression changes and mutant fitness in response to sub-MIC antimicrobials do not correlate on a genomewide scale, indicating that gene expression is not a good predictor of fitness determinants. In general, fewer fitness determinants were identified for antiseptics and disinfectants than for antibiotics. Analysis of gene expression and fitness data together allowed the prediction of antagonistic interactions between antimicrobials and insight into the molecular mechanisms controlling these interactions. IMPORTANCE Infections involving multidrug-resistant pathogens are difficult to treat because the therapeutic options are limited. These infections impose a significant financial burden on infected patients and on health care systems. Despite years of antimicrobial resistance research, we lack a comprehensive understanding of the intrinsic mechanisms controlling antimicrobial resistance. This work uses two fine-scale genomic approaches to identify genetic loci important for antimicrobial resistance of the opportunistic pathogen Pseudomonas aeruginosa. Our results reveal that antibiotics have more resistance determinants than antiseptics/disinfectants and that gene expression upon exposure to antimicrobials is not a good predictor of these resistance determinants. In addition, we show that when used together, genomewide gene expression and fitness profiling can provide mechanistic insights into multidrug resistance mechanisms.open

    Northeast Folklore volume 1 numbers 1-4

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    The first ever issue of Northeast Folklore was published in the spring of 1958 under the editorship of Edward D. Ives (known as Sandy) and Bacil F. Kirtley through the Department of English at the University of Maine. The four editions that year were later bound into a single volume. Table of Contents Number 1 (Spring): Mishaps of a Maine Lobsterman Maine Winter Menus: A Study in Ingenuity “Young Jimmy Foulger:” A Hitherto Unrecorded Ballad in the Northeast John Ellis – Hunter, Guide, Legend Number 2 (Summer): Bibliography of New England-Maritimes Folklore Selected Bibliography of New England-Maritimes Folklore Collections and Studies Prior to 1950 Number 3 (Fall): Folklore from Aroostook County, Maine, and Neighboring Canada The Creation of Folk Songs Number 4 (Winter): Yankee Doodle: An Early Version Two Stories from the Maine Lumberwoods The First Miramichi Folksong Festival Folklore from Aroostook County, Maine, and Neighboring Canadahttps://digitalcommons.library.umaine.edu/nf/1001/thumbnail.jp

    Northeast Folklore volume 1 numbers 1-4

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    The first ever issue of Northeast Folklore was published in the spring of 1958 under the editorship of Edward D. Ives (known as Sandy) and Bacil F. Kirtley through the Department of English at the University of Maine. The four editions that year were later bound into a single volume. Table of Contents Number 1 (Spring): Mishaps of a Maine Lobsterman Maine Winter Menus: A Study in Ingenuity “Young Jimmy Foulger:” A Hitherto Unrecorded Ballad in the Northeast John Ellis – Hunter, Guide, Legend Number 2 (Summer): Bibliography of New England-Maritimes Folklore Selected Bibliography of New England-Maritimes Folklore Collections and Studies Prior to 1950 Number 3 (Fall): Folklore from Aroostook County, Maine, and Neighboring Canada The Creation of Folk Songs Number 4 (Winter): Yankee Doodle: An Early Version Two Stories from the Maine Lumberwoods The First Miramichi Folksong Festival Folklore from Aroostook County, Maine, and Neighboring Canadahttps://digitalcommons.library.umaine.edu/nf/1001/thumbnail.jp

    Osteoinductive PolyHIPE Foams as Injectable Bone Grafts

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    We have recently fabricated biodegradable polyHIPEs as injectable bone grafts and characterized the mechanical properties, pore architecture, and cure rates. In this study, calcium phosphate nanoparticles and demineralized bone matrix (DBM) particles were incorporated into injectable polyHIPE foams to promote osteoblastic differentiation of mesenchymal stem cells (MSCs). Upon incorporation of each type of particle, stable monoliths were formed with compressive properties comparable to control polyHIPEs. Pore size quantification indicated a negligible effect of all particles on emulsion stability and resulting pore architecture. Alizarin red calcium staining illustrated the incorporation of calcium phosphate particles at the pore surface, while picrosirius red collagen staining illustrated collagen-rich DBM particles within the monoliths. Osteoinductive particles had a negligible effect on the compressive modulus (∌30 MPa), which remained comparable to human cancellous bone values. All polyHIPE compositions promoted human MSC viability (∌90%) through 2 weeks. Furthermore, gene expression analysis indicated the ability of all polyHIPE compositions to promote osteogenic differentiation through the upregulation of bone-specific markers compared to a time zero control. These findings illustrate the potential for these osteoinductive polyHIPEs to promote osteogenesis and validate future in vivo evaluation. Overall, this work demonstrates the ability to incorporate a range of bioactive components into propylene fumarate dimethacrylate-based injectable polyHIPEs to increase cellular interactions and direct specific behavior without compromising scaffold architecture and resulting properties for various tissue engineering applications

    The MBA as Careerist: An Analysis of Early-Career Job Change

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    This study examined the job changes of 680 early-career business school graduates. Although a number of anecdotal articles characterize MBAs as overly “careerist” and oriented toward job-hopping, little empirical research has focused on this issue. The research included a direct comparison of job-hopping behavior of MBAs with bachelor S degree graduates, taking into account a number of control variables, including demographic and economic variables. Results indicated that MBAs changed jobs less frequently than bachelor 5 degree graduates, even when a variety of other factors were controlled.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

    Recent radio talks

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    Recent Rural Radio Talks Dairy Hygiene is Important; - D.C. Mickle Farm Water Supplies; - K. Needham Handling the Apple Crop; - K. Whitely Renovation of Irrigated Pastures; - Dairying division More About Lupinosis; - H. W. Bennetts Progress in Doublegee Control; - Norman Halse Changing Practices in Tobacco Growing in W.A.; - G. A. Pearce Progress in doublegee control; - G.A. Pearce Some Uses of Radio Isotopes in Agriculture; - E. N. Fitzpatrick Guildford Grass—Sign of a Run-Down Pasture; - R. A. Bettenay Silage and when to feed it; - R. Bettenay Ants in the Apiary; - R. S. Coleman Bacterial Canker of Stone Fruits; - Olga M. Goss Poison Plants in the Home Garden; - R. D. Royce The Cabbage White Butterfly; - C. F. H. Jenkins Summer Treatments for San Jose Scale; - C. F. H. Jenkins Preparations for Fodder Conservation; - H.G. Cariss Sudan Grass Survived Dry Summer; - R.A. Bettenay Root Maggot Flies; - J. A. Button Fallowing for Cropping; - A.S. Wild Feeding for Milk Quality; - L. C. Snook The Rabbit— Friend or Foe. A. R. Tomlinso

    Effects of warm water intrusions on populations of macrozooplankton on Georges Bank, Northwest Atlantic

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    Author Posting. © The Authors, 2004. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Continental Shelf Research 25 (2005): 143-156, doi:10.1016/j.csr.2004.07.028.As part of the Georges Bank/North West Atlantic GLOBEC (Global Ocean Ecosystems Dynamics) Program, macrozooplankton and micronekton were collected on 30 Broad Scale Survey Cruises between January – June, 1995 –1999, using a 10 m2 MOCNESS (3mm mesh). The objective of this study is to examine the effects of warm water intrusions on populations of macrozooplankton, namely Salpa spp., Phronima spp., Neomysis americana, and Crangon septemspinosa, on Georges Bank. Salpa spp. and Phronima spp. showed a large degree of horizontal co-occurrence, being found predominantly in Upper Slope/Gulf Stream Water and Georges Bank/Gulf of Maine Water. Abundances of these taxa showed striking interannual variability, and were only abundant on the southern flank and in the Northeast Channel in late spring/early summer of 1995 and 1999, periods during which AVHRR imagery and hydrographic data showed the presence of warm water intrusions. These intrusions seemed to have little effect on the distribution of other macrozooplankton (e.g., Neomysis americana and Crangon septemspinosa). Warm water intrusions can directly affect Salpa spp. and Phronima spp. populations by advecting them onto Georges Bank, although other, more resident populations, especially those inside the 100m isobath, seem to be little affected by such intrusions.Additional thanks goes to Tom Niesen and Stan Williams for their advice on data analysis and interpretation. This work was supported by NSF award No. OCE96-17209 and NOAA award No. NA66GP0356 to S. M. Bollens provided from the US GLOBEC Northwest Atlantic/Georges Bank Program, a joint program of the National Science Foundation and the National Oceanic and Atmospheric Administration

    A 'Multiple Lenses' Approach to Policy Change: the Case of Tobacco Policy in the UK

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    This article examines a period of rapid policy change following decades of stability in UK tobacco. It seeks to account for such a long period of policy stability, to analyse and qualify the extent of change, and to explain change using a 'multiple lenses' approach. It compares the explanatory value of policy network models such as punctuated equilibrium and the advocacy coalition framework, with models stressing change from 'above and below' such as multi-level governance and policy transfer. A key finding is that the value of these models varies according to the narrative of policy change that we select. The article challenges researchers to be careful about assuming the nature of policy change before embarking on explanation. While the findings of the case study may vary with other policy areas in British politics, the call for clarity and lessons from multiple approaches are widely applicable

    Ground and In-Flight Calibration of the OSIRIS-REx Camera Suite

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    The OSIRIS-REx Camera Suite (OCAMS) onboard the OSIRIS-REx spacecraft is used to study the shape and surface of the mission’s target, asteroid (101955) Bennu, in support of the selection of a sampling site. We present calibration methods and results for the three OCAMS cameras—MapCam, PolyCam, and SamCam—using data from pre-flight and in-flight calibration campaigns. Pre-flight calibrations established a baseline for a variety of camera properties, including bias and dark behavior, flat fields, stray light, and radiometric calibration. In-flight activities updated these calibrations where possible, allowing us to confidently measure Bennu’s surface. Accurate calibration is critical not only for establishing a global understanding of Bennu, but also for enabling analyses of potential sampling locations and for providing scientific context for the returned sample

    Deformation-induced microstructural banding in TRIP steels

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    Microstructure inhomogeneities can strongly influence the mechanical properties of advanced high-strength steels in a detrimental manner. This study of a transformation-induced plasticity (TRIP) steel investigates the effect of pre-existing contiguous grain boundary networks (CGBNs) of hard second-phases and shows how these develop into bands during tensile testing using in situ observations in conjunction with digital image correlation (DIC). The bands form by the lateral contraction of the soft ferrite matrix, which rotates and displaces the CGBNs of second-phases and the individual features within them to become aligned with the loading direction. The more extensive pre-existing CGBNs that were before the deformation already aligned with the loading direction are the most critical microstructural feature for damage initiation and propagation. They induce micro-void formation between the hard second-phases along them, which coalesce and develop into long macroscopic fissures. The hard phases, retained austenite and martensite, were not differentiated as it was found that the individual phases do not play a role in the formation of these bands. It is suggested that minimizing the presence of CGBNs of hard second-phases in the initial microstructure will increase the formability
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