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Soares A, Edwards A, An D, Bagnoud A, Bradley J, Barnhart E, Bomberg M, Budwill K, Caffrey SM, Fields M, Gralnick J, Kadnikov V, Momper L, Osburn M, Mu A, Moreau JW, Moser D, Purkamo L, Rassner SM, Sheik CS, Sherwood Lollar B, Toner BM, Voordouw G, Wouters K, Mitchell AC. A global perspective on bacterial diversity in the terrestrial deep subsurface. Microbiology (Reading) 2023; 169:001172. [PMID: 36748549 PMCID: PMC9993121 DOI: 10.1099/mic.0.001172] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 03/07/2022] [Indexed: 01/19/2023]
Abstract
While recent efforts to catalogue Earth's microbial diversity have focused upon surface and marine habitats, 12-20 % of Earth's biomass is suggested to exist in the terrestrial deep subsurface, compared to ~1.8 % in the deep subseafloor. Metagenomic studies of the terrestrial deep subsurface have yielded a trove of divergent and functionally important microbiomes from a range of localities. However, a wider perspective of microbial diversity and its relationship to environmental conditions within the terrestrial deep subsurface is still required. Our meta-analysis reveals that terrestrial deep subsurface microbiota are dominated by Betaproteobacteria, Gammaproteobacteria and Firmicutes, probably as a function of the diverse metabolic strategies of these taxa. Evidence was also found for a common small consortium of prevalent Betaproteobacteria and Gammaproteobacteria operational taxonomic units across the localities. This implies a core terrestrial deep subsurface community, irrespective of aquifer lithology, depth and other variables, that may play an important role in colonizing and sustaining microbial habitats in the deep terrestrial subsurface. An in silico contamination-aware approach to analysing this dataset underscores the importance of downstream methods for assuring that robust conclusions can be reached from deep subsurface-derived sequencing data. Understanding the global panorama of microbial diversity and ecological dynamics in the deep terrestrial subsurface provides a first step towards understanding the role of microbes in global subsurface element and nutrient cycling.
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Affiliation(s)
- A. Soares
- Department of Geography and Earth Sciences (DGES), Aberystwyth University (AU), Aberystwyth, UK
- Institute of Biology, Environmental and Rural Sciences (IBERS), AU, Aberystwyth, UK
- Department of Plant and Microbial Biology, University of Minnesota, Minneapolis, MN, USA
- Present address: Group for Aquatic Microbial Ecology (GAME), University of Duisburg-Essen, Campus Essen - Environmental Microbiology and Biotechnology, Universitätsstr. 5, 45141 Essen, Germany
| | - A. Edwards
- Institute of Biology, Environmental and Rural Sciences (IBERS), AU, Aberystwyth, UK
- Interdisciplinary Centre for Environmental Microbiology (iCEM), AU, Aberystwyth, UK
| | - D. An
- Department of Biological Sciences, University of Calgary, Calgary, Canada
| | - A. Bagnoud
- Institut de Génie Thermique (IGT), Haute École d'Ingénierie et de Gestion du Canton de Vaud (HEIG-VD), Yverdon-les-Bains, Switzerland
| | - J. Bradley
- School of Geography, Queen Mary University of London, London, UK
| | - E. Barnhart
- U.S. Geological Survey (USGS), USA, Reston, VA, USA
- Center for Biofilm Engineering (CBE), Montana State University, Bozeman, MT, USA
| | - M. Bomberg
- VTT Technical Research Centre of Finland, Finland
| | | | | | - M. Fields
- Center for Biofilm Engineering (CBE), Montana State University, Bozeman, MT, USA
- Department of Microbiology & Immunology, MSU, Bozeman, MT, USA
| | - J. Gralnick
- Department of Plant and Microbial Biology, University of Minnesota, Minneapolis, MN, USA
| | - V. Kadnikov
- Institute of Bioengineering, Research Center of Biotechnology, Russian Academy of Sciences, Russia
| | - L. Momper
- Department of Earth, Atmospheric and Planetary Sciences (DEAPS), The Massachusetts Institute of Technology (MIT), Cambridge, MA, USA
| | - M. Osburn
- Department of Earth and Planetary Sciences, Northwestern University, Evanston, IL, USA
| | - A. Mu
- Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Australia
- Doherty Applied Microbial Genomics, Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Australia
- Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, University of Melbourne, Melbourne, Australia
| | - J. W. Moreau
- School of Earth Sciences, The University of Melbourne, Parkville, Australia
| | - D. Moser
- Division of Hydrologic Sciences, Desert Research Institute (DRI), Las Vegas, NV, USA
| | - L. Purkamo
- VTT Technical Research Centre of Finland, Finland
- School of Earth and Environmental Sciences (SEES), University of St. Andrews, St. Andrews, UK
- Geological Survey of Finland (GTK), Finland
| | - S. M. Rassner
- Department of Geography and Earth Sciences (DGES), Aberystwyth University (AU), Aberystwyth, UK
- Interdisciplinary Centre for Environmental Microbiology (iCEM), AU, Aberystwyth, UK
| | - C. S. Sheik
- Large Lakes Observatory, University of Minnesota, Duluth, MN, USA
| | | | - B. M. Toner
- Department of Soil, Water & Climate, University of Minnesota, Minneapolis/Saint Paul, MN, USA
| | - G. Voordouw
- Department of Biological Sciences, University of Calgary, Calgary, Canada
| | - K. Wouters
- Institute for Environment, Health and Safety (EHS), Belgian Nuclear Research Centre SCK•CEN, Mol, Belgium
| | - A. C. Mitchell
- Department of Geography and Earth Sciences (DGES), Aberystwyth University (AU), Aberystwyth, UK
- Interdisciplinary Centre for Environmental Microbiology (iCEM), AU, Aberystwyth, UK
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2
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Irvine-Fynn TDL, Edwards A, Stevens IT, Mitchell AC, Bunting P, Box JE, Cameron KA, Cook JM, Naegeli K, Rassner SME, Ryan JC, Stibal M, Williamson CJ, Hubbard A. Storage and export of microbial biomass across the western Greenland Ice Sheet. Nat Commun 2021; 12:3960. [PMID: 34172727 PMCID: PMC8233322 DOI: 10.1038/s41467-021-24040-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Accepted: 05/21/2021] [Indexed: 11/23/2022] Open
Abstract
The Greenland Ice Sheet harbours a wealth of microbial life, yet the total biomass stored or exported from its surface to downstream environments is unconstrained. Here, we quantify microbial abundance and cellular biomass flux within the near-surface weathering crust photic zone of the western sector of the ice sheet. Using groundwater techniques, we demonstrate that interstitial water flow is slow (~10−2 m d−1), while flow cytometry enumeration reveals this pathway delivers 5 × 108 cells m−2 d−1 to supraglacial streams, equivalent to a carbon flux up to 250 g km−2 d−1. We infer that cellular carbon accumulation in the weathering crust exceeds fluvial export, promoting biomass sequestration, enhanced carbon cycling, and biological albedo reduction. We estimate that up to 37 kg km−2 of cellular carbon is flushed from the weathering crust environment of the western Greenland Ice Sheet each summer, providing an appreciable flux to support heterotrophs and methanogenesis at the bed. Microbes that colonise ice sheet surfaces are important to the carbon cycle, but their biomass and transport remains unquantified. Here, the authors reveal substantial microbial carbon fluxes across Greenland’s ice surface, in quantities that may sustain subglacial heterotrophs and fuel methanogenesis.
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Affiliation(s)
- T D L Irvine-Fynn
- Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, UK.
| | - A Edwards
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, UK
| | - I T Stevens
- Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, UK.,School of Geography, Politics and Sociology, Newcastle University, Newcastle-upon-Tyne, UK.,Department of Environmental Science, Aarhus University, Frederiksborgvej, Roskilde, Denmark
| | - A C Mitchell
- Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, UK
| | - P Bunting
- Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, UK
| | - J E Box
- Department of Glaciology and Climate, Geological Survey of Denmark and Greenland, Copenhagen, Denmark
| | - K A Cameron
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, UK.,Department of Glaciology and Climate, Geological Survey of Denmark and Greenland, Copenhagen, Denmark.,School of Geographical and Earth Sciences, University of Glasgow, Glasgow, UK
| | - J M Cook
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, UK.,Department of Environmental Science, Aarhus University, Frederiksborgvej, Roskilde, Denmark.,Department of Geography, University of Sheffield, Sheffield, UK
| | - K Naegeli
- Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, UK.,Institute of Geography and Oeschger Center for Climate Change Research, University of Bern, Bern, Switzerland
| | - S M E Rassner
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, UK
| | - J C Ryan
- Institute at Brown for Environment and Society, Brown University, Providence, RI, USA
| | - M Stibal
- Department of Ecology, Faculty of Science, Charles University, Prague, Czechia
| | - C J Williamson
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, UK
| | - A Hubbard
- Centre for Gas Hydrate, Environment and Climate, Department of Geosciences, UiT-The Arctic University of Norway, Tromsø, Norway.,Geography Research Unit, University of Oulu, Oulu, Finland
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3
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Pimenta D, Barakat MF, Obika BD, Mitchell AC, Lockie TPE. P2669Prognostication in out-of-hospital cardiac arrest. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz748.0987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Out-of-hospital cardiac arrest (OOHCA) remains an area where little progress has been made in outcomes despite significant advances in cardiac care. The OOHCA cohort requires a large amount of resources, including primary coronary intervention and intensive care, often with poor eventual outcomes. A clinical prognostic scoring system would allow resources to be focused on OOHCA patients who are likely to survive; rather than expensive and futile treatments in those who are not. Several different scoring systems have been published but have not been compared in a real world cohort of OOHCA patients.
Method
The Cardiac Arrest Hospital Prognosis (CAHP) score that utilises 7 variables and a simpler three-factor prognostic score derived by Hirt et al were applied retrospectively to a cohort of 157 consecutive OOHCA patients presenting to a regional Centre in our city, UK between 2016 and 2018. For each patient the CAHP score was calculated where a score of >200 predicts a Cerebral Performance Category (CPC) outcome of 3–5 (severe disability, vegetative coma or death). They were also categorised using the Hirt algorithm into “Futile”, “Approaching Futility” and “Non-Futile” groups. CPC outcomes were then compared using both scores and diagnostic accuracy assessed.
Results
A CAHP score of >200 predicted a CPC outcome of 3–5 with 97% specificity and a positive predictive value of 92%. A CAHP score >200 predicted 30-day mortality with 96% specificity, and a positive predictive value of 89% (Fig. 1A). The same cohort categorised by the Hirt algorithm was less accurate; in those patients sorted into the “futile” category 15% of patients survived, and in the “approaching futility” group survival was 100% (Fig. 1B). The specificity and PPV of predicting futility was 94% and 85% respectively.
Conclusion
Although a simple three-factor prognostic score as suggested by Hirt et al is attractive in this cohort of OOHCA patients it did not discriminate those patients who were likely to survive and, the CAHP score was more accurate in predicting outcome. Further validation is required in prospective, multi-centre studies to ensure that application of these scores are reproducible in real-world OOHCA populations in decision making for emergency coronary angiography.
Acknowledgement/Funding
None
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Affiliation(s)
- D Pimenta
- Royal Free Hospital, London, United Kingdom
| | | | - B D Obika
- Royal Free Hospital, London, United Kingdom
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4
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Mitchell AC, McCabe EM, Brown KW. Psychiatrists' attitudes to physical examination of new out-patients with a major depressive disorder. Psychiatr bull 2018. [DOI: 10.1192/pb.22.2.82] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This survey examined Scottish psychiatrists' attitudes to physical examination and appropriate investigations in the routine assessment of new out-patients with a major depressive disorder. A discrepancy exists between current opinion towards and actual practice of physical examination in the assessment of new out-patients with depression. Numerous obstacles to performing investigations were identified including lack of time, inadequate consulting rooms, lack of equipment and lack of chaperon. The many obstacles identified are considerable but not insurmountable. Missed diagnoses may have adverse consequences for patients as well as medico-legal implications.
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5
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Mikucki JA, Lee PA, Ghosh D, Purcell AM, Mitchell AC, Mankoff KD, Fisher AT, Tulaczyk S, Carter S, Siegfried MR, Fricker HA, Hodson T, Coenen J, Powell R, Scherer R, Vick-Majors T, Achberger AA, Christner BC, Tranter M. Subglacial Lake Whillans microbial biogeochemistry: a synthesis of current knowledge. Philos Trans A Math Phys Eng Sci 2016; 374:rsta.2014.0290. [PMID: 26667908 DOI: 10.1098/rsta.2014.0290] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Liquid water occurs below glaciers and ice sheets globally, enabling the existence of an array of aquatic microbial ecosystems. In Antarctica, large subglacial lakes are present beneath hundreds to thousands of metres of ice, and scientific interest in exploring these environments has escalated over the past decade. After years of planning, the first team of scientists and engineers cleanly accessed and retrieved pristine samples from a West Antarctic subglacial lake ecosystem in January 2013. This paper reviews the findings to date on Subglacial Lake Whillans and presents new supporting data on the carbon and energy metabolism of resident microbes. The analysis of water and sediments from the lake revealed a diverse microbial community composed of bacteria and archaea that are close relatives of species known to use reduced N, S or Fe and CH4 as energy sources. The water chemistry of Subglacial Lake Whillans was dominated by weathering products from silicate minerals with a minor influence from seawater. Contributions to water chemistry from microbial sulfide oxidation and carbonation reactions were supported by genomic data. Collectively, these results provide unequivocal evidence that subglacial environments in this region of West Antarctica host active microbial ecosystems that participate in subglacial biogeochemical cycling.
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Affiliation(s)
- J A Mikucki
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, USA Department of Biology, Middlebury College, Middlebury, VT 05753, USA
| | - P A Lee
- Hollings Marine Lab, College of Charleston, Charleston, SC 29412, USA
| | - D Ghosh
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, USA
| | - A M Purcell
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, USA
| | - A C Mitchell
- Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, UK
| | - K D Mankoff
- Department of Geosciences, The Pennsylvania State University, University Park, PA 16802, USA
| | - A T Fisher
- Earth and Planetary Sciences, University of California, Santa Cruz, CA, USA
| | - S Tulaczyk
- Earth and Planetary Sciences, University of California, Santa Cruz, CA, USA
| | - S Carter
- Institute for Geophysics and Planetary Physics, Scripps Institution of Oceanography, University of California, San Diego, CA 92093, USA
| | - M R Siegfried
- Institute for Geophysics and Planetary Physics, Scripps Institution of Oceanography, University of California, San Diego, CA 92093, USA
| | - H A Fricker
- Institute for Geophysics and Planetary Physics, Scripps Institution of Oceanography, University of California, San Diego, CA 92093, USA
| | - T Hodson
- Department of Geology and Environmental Geosciences Northern, Illinois University, DeKalb, IL 60115, USA
| | - J Coenen
- Department of Geology and Environmental Geosciences Northern, Illinois University, DeKalb, IL 60115, USA
| | - R Powell
- Department of Geology and Environmental Geosciences Northern, Illinois University, DeKalb, IL 60115, USA
| | - R Scherer
- Department of Geology and Environmental Geosciences Northern, Illinois University, DeKalb, IL 60115, USA
| | - T Vick-Majors
- Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT 59717, USA
| | - A A Achberger
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
| | - B C Christner
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
| | - M Tranter
- Bristol Glaciology Centre, Geographical Sciences, University of Bristol, Bristol BS8 1SS, UK
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6
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Mitchell AC, Peterson L, Reardon CL, Reed SB, Culley DE, Romine MR, Geesey GG. Role of outer membrane c-type cytochromes MtrC and OmcA in Shewanella oneidensis MR-1 cell production, accumulation, and detachment during respiration on hematite. Geobiology 2012; 10:355-370. [PMID: 22360295 DOI: 10.1111/j.1472-4669.2012.00321.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The iron-reducing bacterium Shewanella oneidensis MR-1 has the capacity to contribute to iron cycling over the long term by respiring on crystalline iron oxides such as hematite when poorly crystalline phases are depleted. The ability of outer membrane cytochromes OmcA and MtrC of MR-1 to bind to and transfer electrons to hematite has led to the suggestion that they function as terminal reductases when this mineral is used as a respiratory substrate. Differences in their redox behavior and hematite-binding properties, however, indicate that they play different roles in the electron transfer reaction. Here, we investigated how these differences in cytochrome behavior with respect to hematite affected biofilm development when the mineral served as terminal electron acceptor (TEA). Upon attachment to hematite, cells of the wild-type (WT) strain as well as those of a ΔomcA mutant but not those of a ΔmtrC mutant replicated and accumulated on the mineral surface. The results indicate that MtrC but not OmcA is required for growth when this mineral serves as TEA. While an OmcA deficiency did not impede cell replication and accumulation on hematite prior to achievement of a maximum surface cell density comparable to that established by WT cells, OmcA was required for efficient electron transfer and cell attachment to hematite once maximum surface cell density was achieved. OmcA may therefore play a role in overcoming barriers to electron transfer and cell attachment to hematite imposed by reductive dissolution of the mineral surface from cell respiration associated with achievement of high surface cell densities.
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Affiliation(s)
- A C Mitchell
- Department of Microbiology and Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
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7
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8
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Abstract
Measurements of rotation rates and gravitational harmonics of Neptune made with the Voyager 2 spacecraft allow tighter constraints on models of the planet's interior. Shock measurements of material that may match the composition of Neptune, the so-calied planetary ;;ice,'' have been carried out to pressures exceeding 200 gigapascals (2 megabars). Comparison of shock data with inferred pressure-density profiles for both Uranus and Neptune shows substantial similarity through most of the mass of both planets. Analysis of the effect of Neptune's strong differential rotation on its gravitational harmonics indicates that differential rotation involves only the outermost few percent of Neptune's mass.
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9
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Mitchell AC, Dad S, Morgan CG. Selective detection of luminescence from semiconductor quantum dots by nanosecond time-gated imaging with a colour-masked CCD detector. J Microsc 2008; 230:172-6. [PMID: 18445145 DOI: 10.1111/j.1365-2818.2008.01973.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Quantum dots are of considerable interest as highly detectable labels with broad absorption, narrow spectral emission and good quantum yields. The luminescence emission has a longer decay time than that of the most common fluorophores, leading to facile rejection of much background emission (such as autofluorescence from biological samples) by means of gated detection. Here, it is shown that a new technique, true-colour nanosecond time-gated luminescence imaging, can be used for selective detection of quantum dot luminescence and should prove valuable for multiplexed detection on the basis of both spectral emission profile and luminescence decay time.
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Affiliation(s)
- A C Mitchell
- Biomedical Sciences Research Institute, School of Environmental and Life Sciences, University of Salford, Salford, United Kingdom
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10
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Morgan CG, Mitchell AC. Prospects for applications of lanthanide-based upconverting surfaces to bioassay and detection. Biosens Bioelectron 2006; 22:1769-75. [PMID: 17005389 DOI: 10.1016/j.bios.2006.08.024] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2006] [Revised: 08/11/2006] [Accepted: 08/18/2006] [Indexed: 11/28/2022]
Abstract
Biological assays to detect binding interactions are often conducted using fluorescence resonance energy transfer (FRET) but this has several disadvantages that markedly reduce the dynamic range of measurements. The very short range of FRET interactions also causes difficulties when large analytes such as viruses or spores are to be detected. Conventional FRET-based assays can in principle be improved using infrared-excited upconverting lanthanide-based energy donors but this does not address the short range of the FRET process. Here we investigate an alternative mode of energy transfer based on evanescent wave coupling from an erbium-doped waveguide to an absorbed fluorophore and characterise the luminescence from the dopant. The upconverted erbium emission is highly structured with well-separated bands in the violet, green and red spectral regions and very little detectable signal between the peaks. The relative intensity of these bands depends on power-density of infrared excitation. Green emission predominates at low power-density and red emission increases more rapidly as power-density increases, with a smaller violet peak also emerging. The temporal response of the upconverting material to pulsed infrared excitation was investigated and was shown to vary markedly with emission wavelength with the red component being particularly sensitive to the duration of the excitation pulse. A surface monolayer of the fluorescent protein R-phycoerythrin was very easily detected on binding to an upconverting waveguide. The potential advantages and limitations of the evanescent wave excitation technique for fluorescence detection are discussed and avenues for further development are considered.
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Affiliation(s)
- C G Morgan
- Biomedical Sciences Research Institute, School of Environmental and Life Sciences, University of Salford, Salford M5 4WT, UK.
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11
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Abstract
Total internal reflection fluorescence microscopy is well known as a means of studying surface-bound structures in cell biology. It is usually measured either by coupling a light source to the sample using a prism or with a special objective where light passing through the periphery of the lens illuminates the contact region beyond the critical angle. In this study we present a new and simple approach to total internal reflection fluorescence microscopy where the sample is mounted on a cover slip prepared from a high-index upconverting glass-ceramic. Excitation of the cover slip with a low-cost near-infrared laser diode generates intense narrow-band visible emission within the cover slip, some of which is totally internally reflected. This emission gives rise to an evanescent wave at the interface and hence can excite surface-bound fluorescent species. Depending on the excitation conditions the cover slip can generate violet, green and red emission and hence can excite a wide range of fluorescent labels. Fluorescence emission from the sample can be detected in spectral regions where the direct emission from the cover slip is very weak. The advantages and limitations of the technique are discussed in comparison with conventional total internal reflection fluorescence microscopy measurements and prospects for novel total internal reflection fluorescence microscopy geometries are considered.
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Affiliation(s)
- C G Morgan
- Biomedical Sciences Research Institute, School of Environmental and Life Sciences, University of Salford, Salford M5 4WT, UK.
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12
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Chau R, Mitchell AC, Minich RW, Nellis WJ. Metallization of fluid nitrogen and the mott transition in highly compressed low-Z fluids. Phys Rev Lett 2003; 90:245501. [PMID: 12857199 DOI: 10.1103/physrevlett.90.245501] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2002] [Indexed: 05/24/2023]
Abstract
Electrical conductivities are reported for degenerate fluid nitrogen at pressures up to 180 GPa (1.8 Mbar) and temperatures of approximately 7000 K. These extreme quasi-isentropic conditions were achieved with multiple-shock compression generated with a two-stage light-gas gun. Nitrogen undergoes a nonmetal-metal transition at 120 GPa, probably in the monatomic state. These N data and previous conductivity data for H, O, Cs, and Rb are used to develop a general picture of the systematics of the nonmetal-metal transition in these fluids. Specifically, the density dependences of electrical conductivities in the semiconducting fluid are well correlated with the radial extent of the electronic charge-density distributions of H, N, O, Cs, and Rb atoms. These new data for N scale with previous data for O, as expected from their similar charge-density distributions.
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Affiliation(s)
- R Chau
- Lawrence Livermore National Laboratory, University of California, Livermore, California 94550, USA
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13
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Abstract
CCD cameras coupled optically to gated image intensifiers have been used for fast time-resolved measurements for some years. Image intensifiers have disadvantages, however, and for some applications it would be better if the image sensor could be gated directly at high speed. Control of the 'charge drain' function on an interline-transfer CCD allows the sensor to be switched rapidly from an insensitive state. The temporal and spatial properties of the charge drain are explored in the present paper and it is shown that nanosecond time resolution with acceptable spatial uniformity can be achieved for a small commercial sensor. A fluorescence lifetime imaging system is demonstrated, based on a repetitively pulsed laser excitation source synchronized to the CCD control circuitry via a programmable delay unit.
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Affiliation(s)
- A C Mitchell
- Photonic Research Systems Ltd, Peel Building, The Crescent, Salford M5 4WT, UK
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14
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Mitchell AC, Wall JE, Murray JG, Morgan CG. Direct modulation of the effective sensitivity of a CCD detector: a new approach to time-resolved fluorescence imaging. J Microsc 2002; 206:225-32. [PMID: 12067367 DOI: 10.1046/j.1365-2818.2002.01029.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In this paper a novel approach to frequency-domain fluorescence lifetime imaging (FLIM) is described. In a CCD camera a single pixel is defined by a charge pattern on a group of electrodes. By modulation of the pattern of voltages defining the pixel structure it is possible to modulate the sensitivity of the CCD at radio frequency. The modulation enhances the noise performance of the CCD, in contrast to the deterioration in performance seen when an intensifier stage is similarly modulated. The new technology has potential applications to a wide range of assays as well as in conventional FLIM applications. Unlike intensifier-based systems, the directly modulated CCD is physically small, inexpensive, robust and offers superior resolution and noise performance.
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Affiliation(s)
- A C Mitchell
- Photonic Research Systems Ltd, Peel Building, The Crescent, Salford M5 4WT, UK
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15
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Nellis WJ, Hamilton DC, Mitchell AC. Electrical conductivities of methane, benzene, and polybutene shock compressed to 60 GPa (600 kbar). J Chem Phys 2001. [DOI: 10.1063/1.1379537] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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16
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Abstract
The effective treatment of patients suffering from a variety of difficult pain syndromes, including phantom pain and other neuropathic pains, remains a clinical challenge. Neuropathic pain has been shown to respond to drugs that block the N-methyl-D-aspartate (NMDA) receptor, such as ketamine and amantidine. A 44-year-old woman with a previous right-sided forequarter amputation presented to the Palliative Medicine Team complaining of neuropathic pain in her left arm, which was neurologically intact. The pain was treated with repeated infusions of intravenous ketamine. Twenty-one infusions were given over a period of four months. The pain intensity experienced by the patient lessened as the frequency of the ketamine infusions increased. This finding has not been described previously and supports the theory that there may be an optimum frequency of ketamine infusions to achieve adequate pain control.
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Affiliation(s)
- A C Mitchell
- Department of Palliative Medicine, Beatson Oncology Centre, Glasgow, Scotland, United Kingdom
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Bastea M, Mitchell AC, Nellis WJ. High pressure insulator-metal transition in molecular fluid oxygen. Phys Rev Lett 2001; 86:3108-3111. [PMID: 11290119 DOI: 10.1103/physrevlett.86.3108] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2000] [Indexed: 05/23/2023]
Abstract
We report the first experimental evidence for a metallic phase in fluid molecular oxygen. Our electrical conductivity measurements of fluid oxygen under dynamic quasi-isentropic compression show that a nonmetal-metal transition occurs at 3.4 fold compression, 4500 K, and 1.2 Mbar. We discuss the main features of the electrical conductivity dependence on density and temperature and give an interpretation of the nature of the electrical transport mechanisms in fluid oxygen at these extreme conditions.
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Affiliation(s)
- M Bastea
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550, USA.
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18
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Chau R, Mitchell AC, Minich RW, Nellis WJ. Electrical conductivity of water compressed dynamically to pressures of 70–180 GPa (0.7–1.8 Mbar). J Chem Phys 2001. [DOI: 10.1063/1.1332079] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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19
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Affiliation(s)
- A C Mitchell
- Department of Palliative Medicine, Beatson Oncology Centre, Glasgow, UK.
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20
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Bisby RH, Mead C, Mitchell AC, Morgan CG. Fast laser-induced solute release from liposomes sensitized with photochromic lipid: effects of temperature, lipid host, and sensitizer concentration. Biochem Biophys Res Commun 1999; 262:406-10. [PMID: 10462488 DOI: 10.1006/bbrc.1999.1206] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Liposomes of gel-phase phospholipid have been prepared containing a photochromic lipid sensitizer. A fast UV laser pulse isomerizes the sensitizer destabilizing the lipid bilayer structure and causing release of trapped solute. The kinetics of solute release have been investigated as a function of host lipid chain length, sensitizer concentration, and temperature, and the limits of liposome stability have been established. At low concentrations of sensitizer, pulsed laser irradiation induces some solute release when continuous UV illumination is ineffective. Although rates of solute release usually increase with temperature, at low sensitizer concentration in a rigid host, leakage at first increases but then decreases rapidly above a threshold temperature. The results presented are relevant to the design of photostimulated drug delivery systems and to potential applications of photosensitive liposomes as caging agents for biological effectors.
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Affiliation(s)
- R H Bisby
- Science Research Institute, University of Salford, Salford, M5 4WT, United Kingdom.
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21
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Nellis WJ, Holmes NC, Mitchell AC, Hamilton DC, Nicol M. Equation of state and electrical conductivity of “synthetic Uranus,” a mixture of water, ammonia, and isopropanol, at shock pressure up to 200 GPa (2 Mbar). J Chem Phys 1997. [DOI: 10.1063/1.475200] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- W. J. Nellis
- Lawrence Livermore National Laboratory, University of California, Livermore, California 94550
| | - N. C. Holmes
- Lawrence Livermore National Laboratory, University of California, Livermore, California 94550
| | - A. C. Mitchell
- Lawrence Livermore National Laboratory, University of California, Livermore, California 94550
| | - D. C. Hamilton
- Lawrence Livermore National Laboratory, University of California, Livermore, California 94550
| | - M. Nicol
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90024
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Abstract
Electrical conductivities of molecular hydrogen in Jupiter were calculated by scaling electrical conductivities measured at shock pressures in the range of 10 to 180 gigapascals (0.1 to 1.8 megabars) and temperatures to 4000 kelvin, representative of conditions inside Jupiter. Jupiter's magnetic field is caused by convective dynamo motion of electrically conducting fluid hydrogen. The data imply that Jupiter should become metallic at 140 gigapascals in the fluid, and the electrical conductivity in the jovian molecular envelope at pressures up to metallization is about an order of magnitude larger than expected previously. The large magnetic field is produced in the molecular envelope closer to the surface than previously thought.
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Affiliation(s)
- W J Nellis
- Lawrence Livermore National Laboratory, University of California, Livermore, CA 94550, USA
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24
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Abstract
Fluorescence microscopy is an important tool for biological research, in part because of the extremely high detection sensitivity that can be achieved, but also because fluorescent molecules can be used as probes on account of their environmental responsiveness, for example to measure intracellular pH or metal ion concentration. Unfortunately, the environmental sensitivity can sometimes be a source of problems because of enhancement or 'quenching', which can make it very difficult to relate emission intensity to the amount of fluorophore present. The measured intensity is essentially proportional to the product of the amount of fluorophore present in the sample and the local quantum yield of the fluorophore (the quantum yield can be thought of as the probability that an excited molecule decays by fluorescence emission rather than by other non-radiative processes). This is a particular difficulty in an environment such as a cell or tissue slice in which quantum yield and flurophore concentration can both vary within the sample. Ideally we would wish to be able to measure the quantum yield of fluorescence as well as the fluorescence intensity, as this would allow environmental effects to be compensated for. Unfortunately, this is not at all easy, and indirect means to achieve the same goal are more appropriate. A recently introduced technique, fluorescence lifetime imaging (Morgan et al. 1992, Wang et al. 1992), offers one such means to improve quantification of fluorescence microscopy. In addition, as will be explained, the technique offers the prospect of significantly improving detection sensitivity in appropriate circumstances.
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Affiliation(s)
- C G Morgan
- Department of Biological Sciences, University of Salford, UK
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Morgan CG, Bisby RH, Johnson SA, Mitchell AC. Fast solute release from photosensitive liposomes: an alternative to 'caged' reagents for use in biological systems. FEBS Lett 1995; 375:113-6. [PMID: 7498457 DOI: 10.1016/0014-5793(95)01193-i] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The kinetics of release of soluble marker trapped in liposomes of gel phase phospholipid containing a photoisomerisable phospholipid analogue have been investigated. Marker release is triggered by UV laser flash photolysis at 355 nm. A markedly temperature-dependent release rate is seen, and above 25 degrees C millisecond release kinetics can be achieved. These results suggest that such liposomes might find application as an alternative to conventional 'caged' reagents for photo-triggered reagent release in biological research.
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Affiliation(s)
- C G Morgan
- Department of Biological Sciences, University of Salford, UK
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Morgan CG, Yianni YP, Sandhu SS, Mitchell AC. Liposome fusion and lipid exchange on ultraviolet irradiation of liposomes containing a photochromic phospholipid. Photochem Photobiol 1995; 62:24-9. [PMID: 7638269 DOI: 10.1111/j.1751-1097.1995.tb05233.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A photochromic phospholipid, 1,2-bis[4-4(4-n-butylphenylazo) phenylbutyroyl] phosphatidylcholine (Bis-Azo PC) has been incorporated into liposomes of gel- and liquid-crystalline- phase phospholipids. Liposomes of gel-phase phospholipid are stable in the presence of the trans photostationary state Bis-Azo PC and can encapsulate fluorescent marker dye. On photoisomerization to the cis photostationary state, trapped marker is rapidly released. Liposomes containing Bis-Azo PC can rapidly fuse together after UV isomerization, this process continuing in the dark. Exposure to white light causes reversion of Bis-Azo Pc to the trans form and halts dye leakage and vesicle fusion. Both unilamellar and multilamellar liposomes are able to fuse together on UV exposure. On UV photolysis, liposomes containing Bis-Azo PC do not fuse with a large excess of unlabeled liposomes, but transfer of Bis-Azo PC can be demonstrated spectrophotometrically. Vesicles of pure gel-phase lipid containing trapped marker dye but initially no Bis-Azo PC become leaky as a result of this lipid transfer. Liposomes composed of liquid-crystalline-phase phosphatidylcholine- containing Bis-Azo PC neither leak trapped marker no fuse together on photolysis, nor do liquid-crystalline-phase liposomes fuse with gel-phase liposomes under these conditions. These results are discussed together with some possible applications of liposome photodestabilization.
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Affiliation(s)
- C G Morgan
- Department of Biological Sciences, University of Salford, UK
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Abstract
Recent legislation such as the Americans with Disabilities Act will have a significant impact on higher education in nursing. A survey was conducted to describe the extent to which BSN and ADN nursing programs in the United States admit and graduate special needs and chronically ill students, and to identify the accommodations which have been successful in providing nursing education to these students. Responses received from 86 schools of nursing in 44 states indicated that most schools have had contact with students with special needs such as visual, hearing, or mobility impairments, learning disabilities, and mental or chronic illnesses. Learning disabilities and mental impairment were cited most frequently as having been present among the student population. Few programs have had experience with students with vision problems. While most programs responding had little experience with providing special accommodations to special needs students, most were aware of accessibility on their campuses. Recent legislation aimed at creating opportunities for disabled individuals to successfully enter the work force creates challenges for schools of nursing in education of students with special needs. Issues are raised that must be addressed to meet this important challenge.
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Affiliation(s)
- J K Magilvy
- School of Nursing, University of Colorado Health Sciences Center, Denver 80262
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Nellis WJ, Mitchell AC, McCandless PC, Erskine DJ, Weir ST. Electronic energy gap of molecular hydrogen from electrical conductivity measurements at high shock pressures. Phys Rev Lett 1992; 68:2937-2940. [PMID: 10045533 DOI: 10.1103/physrevlett.68.2937] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Nellis WJ, Mitchell AC, Ree FH, Ross M, Holmes NC, Trainor RJ, Erskine DJ. Equation of state of shock‐compressed liquids: Carbon dioxide and air. J Chem Phys 1991. [DOI: 10.1063/1.461665] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Nellis WJ, Radousky HB, Hamilton DC, Mitchell AC, Holmes NC, Christianson KB, van Thiel M. Equation‐of‐state, shock‐temperature, and electrical‐conductivity data of dense fluid nitrogen in the region of the dissociative phase transition. J Chem Phys 1991. [DOI: 10.1063/1.459895] [Citation(s) in RCA: 101] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Radousky HB, Mitchell AC, Nellis WJ. Shock temperature measurements of planetary ices: NH3, CH4, and ‘‘synthetic Uranus’’. J Chem Phys 1990. [DOI: 10.1063/1.459302] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Nellis WJ, Hamilton DC, Holmes NC, Radousky HB, Ree FH, Mitchell AC, Nicol M. The Nature of the Interior of Uranus Based on Studies of Planetary Ices at High Dynamic Pressure. Science 1988; 240:779-81. [PMID: 17741451 DOI: 10.1126/science.240.4853.779] [Citation(s) in RCA: 92] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Data from the Voyager II spacecraft showed that Uranus has a large magnetic field with geometry similar to an offset tilted dipole. To interpret the origin of the magnetic field, measurements were made of electrical conductivity and equation-of-state data of the planetary "ices" ammonia, methane, and "synthetic Uranus" at shock pressures and temperatures up to 75 gigapascals and 5000 K. These pressures and temperatures correspond to conditions at the depths at which the surface magnetic field is generated. Above 40 gigapascals the conductivities of synthetic Uranus, water, and ammonia plateau at about 20(ohm-cm)(-1), providing an upper limit for the electrical conductivity used in kinematic or dynamo calculations. The nature of materials at the extreme conditions in the interior is discussed.
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Hamilton DC, Nellis WJ, Mitchell AC, Ree FH, van Thiel M. Electrical conductivity and equation of state of shock‐compressed liquid oxygen. J Chem Phys 1988. [DOI: 10.1063/1.454657] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Nellis WJ, Moriarty JA, Mitchell AC, Ross M, Dandrea RG, Ashcroft NW, Holmes NC, Gathers GR. Metals physics at ultrahigh pressure: Aluminum, copper, and lead as prototypes. Phys Rev Lett 1988; 60:1414-1417. [PMID: 10038032 DOI: 10.1103/physrevlett.60.1414] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Morgan CG, Thomas EW, Sandhu SS, Yianni YP, Mitchell AC. Light-induced fusion of liposomes with release of trapped marker dye is sensitised by photochromic phospholipid. Biochim Biophys Acta 1987; 903:504-9. [PMID: 3663656 DOI: 10.1016/0005-2736(87)90057-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Liposomes have been prepared from dipalmitoylphosphatidylcholine containing small amounts of a synthetic photochromic phospholipid, 'Bis-Azo PC'. In the dark, these are stable at room temperature, and contents do not significantly leak over weeks. Photoisomerisation results in immediate release of trapped marker, and in liposome fusion to form larger structures. Fusion has been detected using a fluorescence polarisation assay, and confirmed by electron microscopy. In mixtures, fusion occurs between 'photochromic' liposomes and those of pure lipid. Bis-Azo PC contains two photochromic acyl chains; analogues bearing a single photochromic chain appear to have little effect on bilayer permeability after isomerisation. Photo-induced leakage and liposome fusion suggest possible applications for localised drug delivery as an adjunct to phototherapy. The ability to non-invasively trigger fusion processes should be useful in fundamental studies of membrane interactions. We believe this to be the first report of photo-induced fusion to date.
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Affiliation(s)
- C G Morgan
- Department of Biological Sciences, University of Salford, U.K
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Radousky HB, Nellis WJ, Ross M, Hamilton DC, Mitchell AC. Molecular dissociation and shock-induced cooling in fluid nitrogen at high densities and temperatures. Phys Rev Lett 1986; 57:2419-2422. [PMID: 10033720 DOI: 10.1103/physrevlett.57.2419] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Nellis WJ, Ree FH, Trainor RJ, Mitchell AC, Boslough MB. Equation of state and optical luminosity of benzene, polybutene, and polyethylene shocked to 210 GPa (2.1 Mbar). J Chem Phys 1984. [DOI: 10.1063/1.447027] [Citation(s) in RCA: 94] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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42
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Elliott RV, Mitchell AC. Foundation report. New guidelines for chronic pain management. Colo Med 1983; 80:307-10. [PMID: 6197224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Nellis WJ, Mitchell AC, van Thiel M, Devine GJ, Trainor RJ, Brown N. Equation‐of‐state data for molecular hydrogen and deuterium at shock pressures in the range 2–76 GPa (20–760 kbar)a). J Chem Phys 1983. [DOI: 10.1063/1.445938] [Citation(s) in RCA: 214] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Mitchell AC. The hospital medical staff--1983. Colo Med 1983; 80:188-90. [PMID: 6627856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Mitchell AC, Nellis WJ. Equation of state and electrical conductivity of water and ammonia shocked to the 100 GPa (1 Mbar) pressure range. J Chem Phys 1982. [DOI: 10.1063/1.443030] [Citation(s) in RCA: 219] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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47
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Nellis WJ, Ree FH, van Thiel M, Mitchell AC. Shock compression of liquid carbon monoxide and methane to 90 GPa (900 kbar). J Chem Phys 1981. [DOI: 10.1063/1.442401] [Citation(s) in RCA: 118] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Mitchell AC. Barriers to therapeutic communication with black clients. Nurs Outlook 1978; 26:109-12. [PMID: 245615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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