Publications by authors named "McGhee G"

Cranberry (, L.) is a commercial small fruit that is native to North America. Oregon ranks fourth in cranberry production in the U.

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Coating thermal noise is one of the dominant noise sources in current gravitational wave detectors and ultimately limits their ability to observe weaker or more distant astronomical sources. This Letter presents investigations of TiO_{2} mixed with SiO_{2} (TiO_{2}:SiO_{2}) as a coating material. We find that, after heat treatment for 100 h at 850 °C, thermal noise of a highly reflective coating comprising of TiO_{2}:SiO_{2} and SiO_{2} reduces to 76% of the current levels in the Advanced LIGO and Advanced Virgo detectors-with potential for reaching 45%, if we assume the mechanical loss of state-of-the-art SiO_{2} layers.

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Article Synopsis
  • The study investigates compact binary coalescences with at least one component mass between 0.2 and 1.0 solar masses using data from Advanced LIGO and Advanced Virgo detectors over six months in 2019, but they found no significant gravitational wave candidates.
  • The analysis leads to an upper limit on the merger rate of subsolar binaries ranging from 220 to 24,200 Gpc⁻³ yr⁻¹, based on the detected signals’ false alarm rate.
  • The researchers use these limits to set new constraints on two models for subsolar-mass compact objects: primordial black holes (suggesting they make up less than 6% of dark matter) and
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As molecular genetic techniques improve and sequence data becomes available for more fungal species, taxonomic classifications historically based upon growth morphology alone are being revisited and occasionally reclassified. Herein, we present such an instance for the fungal pathogen that causes dry berry disease of caneberries. The organism was previously described as the basidiomycete fungus based upon the pathogen's production of Rhizoctonia-like angular branching hyphae.

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We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection.

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is a plant pathogen causing necrotrophic fire blight disease of apple, pear, and other rosaceous plants. This bacterium colonizes host vascular tissues via the production of exopolysaccharides (EPSs) including amylovoran. It is well-established that the nearly ubiquitous plasmid pEA29 of is an essential virulence factor, but the underlying mechanism remains uncharacterized.

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Thermal noise associated with the mechanical loss of current highly reflective mirror coatings is a critical limit to the sensitivity of gravitational-wave detectors. Several alternative coating materials show potential for reducing thermal noise, but cannot be used due to their high optical absorption. Multimaterial coatings have been proposed to enable the use of such materials to reduce thermal noise while minimizing their impact on the total absorption of the mirror coating.

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Convergent evolution reveals to us that the number of possibilities available for contingent events is limited, that historically contingent evolution is constrained to occur within a finite number of limited pathways, and that contingent evolution is thus probabilistic and predictable. That is, the phenomenon of convergence proves that truly contingent evolutionary processes can repeatedly produce the same, or very similar, organic designs in nature and that evolution is directional in these cases. For this reason it is argued in this paper that evolution can be directional without being teleological, and that the dichotomy that evolution must either be directionless and unpredictable or directional and predetermined (teleological) is false.

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Limits in the evolution of biological form can be empirically demonstrated by using theoretical morphospace analyses, and actual analytic examples are given for univalved ammonoid shell form, bivalved brachiopod shell form and helical bryozoan colony form. Limits in the evolution of form in these animal groups can be shown to be due to functional and developmental constraints on possible evolutionary trajectories in morphospace. Future evolutionary-limit research is needed to analyse the possible existence of temporal constraint in the evolution of biological form on Earth, and in the search for the possible existence of functional alien life forms on Titan and Triton that are developmentally impossible for Earth life.

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In surveys from 2006 to 2014, streptomycin resistance in Erwinia amylovora from pear-growing areas in California declined from very high incidence in 2006 and 2007 to very low incidence in 2013 and 2014. The majority of resistant strains were designated as moderately resistant-low (MR-L), and were almost exclusively found in Sacramento County, whereas highly resistant (HR) strains were only recovered in Sutter-Yuba and San Joaquin counties. Resistance of HR strains was associated with a mutation in codon 43 of the chromosomal rpsL gene that results in a change from lysine to arginine, the same mutation that was originally reported for resistant strains from California in the mid-1970s.

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Management of fire blight is complicated by limitations on use of antibiotics in agriculture, antibiotic resistance development, and limited efficacy of alternative control agents. Even though successful in control, preventive antibiotic sprays also affect non-target bacteria, aiding the selection for resistance which could ultimately be transferred to the pathogen Erwinia amylovora. Trunk injection is a target-precise pesticide delivery method that utilizes tree xylem to distribute injected compounds.

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Clustered regularly interspaced short palindromic repeats (CRISPRs) comprise a family of short DNA repeat sequences that are separated by non repetitive spacer sequences and, in combination with a suite of Cas proteins, are thought to function as an adaptive immune system against invading DNA. The number of CRISPR arrays in a bacterial chromosome is variable, and the content of each array can differ in both repeat number and in the presence or absence of specific spacers. We utilized a comparative sequence analysis of CRISPR arrays of the plant pathogen Erwinia amylovora to uncover previously unknown genetic diversity in this species.

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This article explores the skills needed for effective communication with people who have dementia. It describes the factors that influence the communication process and the effect this may have on the nurse-patient therapeutic relationship. Cognitive impairment in people with dementia may limit their ability to communicate effectively.

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The emergence and spread of streptomycin-resistant strains of Erwinia amylovora in Michigan has necessitated the evaluation of new compounds effective for fire blight control. The aminoglycoside antibiotic kasugamycin (Ks) targets the bacterial ribosome and is particularly active against E. amylovora.

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Streptomycin-resistant (Sm(R)) strains of the fire blight pathogen Erwinia amylovora were first isolated in southwest Michigan in 1991. Since that time, resistant strains have progressed northward to other apple-producing regions in the state. A total of 98.

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This study focused on the relationship that develops between professional key workers and dementia carers operating within the home environment. Some research has been directed towards those caring for a relative/friend with dementia and how their role might be made less burdensome; however, the relationship that exists and develops between a carer and their key professional is limited. The aim of this study was to examine this relationship in greater detail and generate a theoretical explanation of this psychosocial process.

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This article illustrates how the concept of reflexivity has matured in conjunction with developments in qualitative research, and makes the case for inclusion of a reflexive account to increase the rigour of the research process. A qualitative study (Jootun and McGhee 2006) is used to show how the reflexive process improved data reliability. Reflexivity is an invaluable tool to promote understanding of the phenomenon under study and the researcher's role.

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Erwinia amylovora, the causal agent of fire blight, is an enterobacterial pathogen of Rosaceous plants including apple and pear. We have been studying the response of E. amylovora to oxidative stress because, during infection, the bacterium elicits an oxidative burst response in host plants.

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ABSTRACT Four Erwinia strains, originally isolated in Japan from pear trees with bacterial shoot blight symptoms, were analyzed to determine their genetic relationship with Erwinia amylovora and E. pyrifoliae. When genomes were characterized with amplified fragment length polymorphism markers and by comparative groEL sequence analysis, the Japanese Erwinia sp.

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Aim: This paper is a report of a discussion of the arguments surrounding the role of the initial literature review in grounded theory.

Background: Researchers new to grounded theory may find themselves confused about the literature review, something we ourselves experienced, pointing to the need for clarity about use of the literature in grounded theory to help guide others about to embark on similar research journeys.

Discussion: The arguments for and against the use of a substantial topic-related initial literature review in a grounded theory study are discussed, giving examples from our own studies.

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The nucleotide sequences, genetic organization, and distribution of plasmids pEU30 (30,314 bp) and pEL60 (60,145 bp) from the plant pathogen Erwinia amylovora are described. The newly characterized pEU30 and pEL60 plasmids inhabited strains isolated in the western United States and Lebanon, respectively. The gene content of pEU30 resembled plasmids found in plant-associated bacteria, while that of pEL60 was most similar to IncL/M plasmids inhabiting enteric bacteria.

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Background: Research in nursing schools still falls behind that in other disciplines. Schools need to develop a good research culture, in which those undertaking and supervising research are supported and guided. This requires commitment from management and effective leadership.

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The plant pathogen Erwinia pyrifoliae has been classified as a separate species from Erwinia amylovora based in part on differences in molecular properties. In this study, these and other molecular properties were examined for E. pyrifoliae and for additional strains of E.

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