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Stegner MA, Hadly EA, Barnosky AD, La Selle S, Sherrod B, Anderson RS, Redondo SA, Viteri MC, Weaver KL, Cundy AB, Gaca P, Rose NL, Yang H, Roberts SL, Hajdas I, Black BA, Spanbauer TL. The Searsville Lake Site (California, USA) as a candidate Global boundary Stratotype Section and Point for the Anthropocene series. Anthropocene Rev 2023; 10:116-145. [PMID: 37213212 PMCID: PMC10193828 DOI: 10.1177/20530196221144098] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Cores from Searsville Lake within Stanford University's Jasper Ridge Biological Preserve, California, USA, are examined to identify a potential GSSP for the Anthropocene: core JRBP2018-VC01B (944.5 cm-long) and tightly correlated JRBP2018-VC01A (852.5 cm-long). Spanning from 1900 CE ± 3 years to 2018 CE, a secure chronology resolved to the sub-annual level allows detailed exploration of the Holocene-Anthropocene transition. We identify the primary GSSP marker as first appearance of 239,240Pu (372-374 cm) in JRBP2018-VC01B and designate the GSSP depth as the distinct boundary between wet and dry season at 366 cm (6 cm above the first sample containing 239,240Pu) and corresponding to October-December 1948 CE. This is consistent with a lag of 1-2 years between ejection of 239,240Pu into the atmosphere and deposition. Auxiliary markers include: first appearance of 137Cs in 1958; late 20th-century decreases in δ15N; late 20th-century elevation in SCPs, Hg, Pb, and other heavy metals; and changes in abundance and presence of ostracod, algae, rotifer and protozoan microfossils. Fossil pollen document anthropogenic landscape changes related to logging and agriculture. As part of a major university, the Searsville site has long been used for research and education, serves users locally to internationally, and is protected yet accessible for future studies and communication about the Anthropocene. Plain Word Summary The Global boundary Stratotype Section and Point (GSSP) for the proposed Anthropocene Series/Epoch is suggested to lie in sediments accumulated over the last ~120 years in Searsville Lake, Woodside, California, USA. The site fulfills all of the ideal criteria for defining and placing a GSSP. In addition, the Searsville site is particularly appropriate to mark the onset of the Anthropocene, because it was anthropogenic activities-the damming of a watershed-that created a geologic record that now preserves the very signals that can be used to recognize the Anthropocene worldwide.
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Scott Anderson R, Allison Stegner M, La Selle S, Sherrod B, Barnosky AD, Hadly EA. Witnessing history: comparison of a century of sedimentary and written records in a California protected area. Reg Environ Change 2023; 23:65. [PMID: 37125024 PMCID: PMC10116087 DOI: 10.1007/s10113-023-02056-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 03/04/2023] [Indexed: 05/03/2023]
Abstract
We use a combination of proxy records from a high-resolution analysis of sediments from Searsville Lake and adjacent Upper Lake Marsh and historical records to document over one and a half centuries of vegetation and socio-ecological change-relating to logging, agricultural land use change, dam construction, chemical applications, recreation, and other drivers-on the San Francisco Peninsula. A relatively open vegetation with minimal oak (Quercus) and coast redwood (Sequoia sempervirens) in the late 1850s reflects widespread logging and grazing during the nineteenth century. Forest and woodland expansion occurred in the early twentieth century, with forests composed of coast redwood and oak, among other taxa, as both logging and grazing declined. Invasive species include those associated with pasturage (Rume x, Plantago), landscape disturbance (Urtica, Amaranthaceae), planting for wood production and wind barriers (Eucalyptus), and agriculture. Agricultural species, including wheat, rye, and corn, were more common in the early twentieth century than subsequently. Wetland and aquatic pollen and fungal spores document a complex hydrological history, often associated with fluctuating water levels, application of algaecides, raising of Searsville Dam, and construction of a levee. By pairing the paleoecological and historical records of both lakes, we have been able to reconstruct the previously undocumented impacts of socio-ecological influences on this drainage, all of which overprinted known climate changes. Recognizing the ecological manifestations of these impacts puts into perspective the extent to which people have interacted with and transformed the environment in the transition into the Anthropocene. Supplementary Information The online version contains supplementary material available at 10.1007/s10113-023-02056-9.
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Affiliation(s)
- R. Scott Anderson
- School of Earth and Sustainability, Northern Arizona University, Flagstaff, AZ USA
| | - M. Allison Stegner
- Department of Biology and Jasper Ridge Biological Preserve, Stanford University, Stanford, CA USA
| | - SeanPaul La Selle
- United States Geological Survey Pacific Coastal and Marine Science Center, Santa Cruz, CA USA
| | - Brian Sherrod
- United States Geological Survey Earthquake Science Center at Department of Earth and Space Sciences, University of Washington, Seattle, WA USA
| | - Anthony D. Barnosky
- Department of Biology and Jasper Ridge Biological Preserve, Stanford University, Stanford, CA USA
| | - Elizabeth A. Hadly
- Department of Biology and Jasper Ridge Biological Preserve, Stanford University, Stanford, CA USA
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Mychajliw AM, Ellwood ER, Alagona PS, Anderson RS, Balisi MA, Biber E, Brown JL, George J, Hendy AJW, Higgins L, Hofman CA, Leger A, Ordeñana MA, Pauly GB, Putman BJ, Randall JM, Riley SPD, Shultz AJ, Stegner MA, Wake TA, Lindsey EL. Lessons for conservation from beneath the pavement. Conserv Biol 2022; 36:e13983. [PMID: 36069058 DOI: 10.1111/cobi.13983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 05/25/2022] [Accepted: 06/10/2022] [Indexed: 06/15/2023]
Affiliation(s)
- Alexis M Mychajliw
- La Brea Tar Pits & Museum, Los Angeles, California, USA
- Department of Biology and Environmental Studies Program, Middlebury College, Middlebury, Vermont, USA
| | - Elizabeth R Ellwood
- La Brea Tar Pits & Museum, Los Angeles, California, USA
- iDigBio, Florida Museum of Natural History, University of Florida, Gainesville, Florida, USA
| | - Peter S Alagona
- Environmental Studies Program, University of California, Santa Barbara, Santa Barbara, California, USA
| | - R Scott Anderson
- School of Earth and Sustainability, Northern Arizona University, Flagstaff, Arizona, USA
| | - Mairin A Balisi
- La Brea Tar Pits & Museum, Los Angeles, California, USA
- Department of Life and Environmental Sciences, University of California, Merced, Merced, California, USA
- Raymond M. Alf Museum of Paleontology, The Webb Schools, Claremont, California, USA
| | - Eric Biber
- School of Law, University of California, Berkeley, Berkeley, California, USA
| | - Justin L Brown
- National Park Service, Santa Monica Mountains National Recreation Area, Thousand Oaks, California, USA
| | - Jessie George
- Department of Geography, University of California, Los Angeles, Los Angeles, California, USA
| | - Austin J W Hendy
- Department of Invertebrate Paleontology, Natural History Museum of Los Angeles County, Los Angeles, California, USA
| | - Lila Higgins
- Community Science Program, Natural History Museum of Los Angeles County, Los Angeles, California, USA
- Urban Nature Research Center, Natural History Museum of Los Angeles County, Los Angeles, California, USA
| | - Courtney A Hofman
- Department of Anthropology, University of Oklahoma, Norman, Oklahoma, USA
- Laboratories of Molecular Anthropology & Microbiome Research, University of Oklahoma, Norman, Oklahoma, USA
| | - Ashley Leger
- Cogstone Resource Management, Orange, California, USA
| | - Miguel A Ordeñana
- Community Science Program, Natural History Museum of Los Angeles County, Los Angeles, California, USA
- Urban Nature Research Center, Natural History Museum of Los Angeles County, Los Angeles, California, USA
| | - Gregory B Pauly
- Urban Nature Research Center, Natural History Museum of Los Angeles County, Los Angeles, California, USA
- Department of Herpetology, Natural History Museum of Los Angeles County, Los Angeles, California, USA
| | - Breanna J Putman
- Urban Nature Research Center, Natural History Museum of Los Angeles County, Los Angeles, California, USA
- Department of Biology, California State University, San Bernardino, California, USA
| | - John M Randall
- The Nature Conservancy, California Chapter, San Diego, California, USA
| | - Seth P D Riley
- National Park Service, Santa Monica Mountains National Recreation Area, Thousand Oaks, California, USA
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, California, USA
| | - Allison J Shultz
- Department of Ornithology, Natural History Museum of Los Angeles County, Los Angeles, California, USA
| | - M Allison Stegner
- Jasper Ridge Biological Preserve, Stanford University, California, USA
- Department of Biology, Stanford University, Stanford, California, USA
| | - Thomas A Wake
- The Cotsen Institute of Archaeology, University of California, Los Angeles, Los Angeles, California, USA
- Department of Anthropology, University of California, Los Angeles, Los Angeles, California, USA
| | - Emily L Lindsey
- La Brea Tar Pits & Museum, Los Angeles, California, USA
- Institute of the Environment and Sustainability, University of California, Los Angeles, Los Angeles, California, USA
- Department of Earth Sciences, University of Southern California, Los Angeles, California, USA
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Cochran W, Shah P, Barker L, Langlee J, Freed K, Boyer L, Scott Anderson R, Belden M, Bannon J, Kates OS, Permpalung N, Mostafa H, Segev DL, Brennan DC, Avery RK. COVID-19 Clinical Outcomes in Solid Organ Transplant Recipients During the Omicron Surge. Transplantation 2022; 106:e346-e347. [PMID: 35404880 PMCID: PMC9213060 DOI: 10.1097/tp.0000000000004162] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/04/2022] [Accepted: 03/10/2022] [Indexed: 11/29/2022]
Affiliation(s)
- Willa Cochran
- Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD
- Comprehensive Transplant Center, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Pali Shah
- Comprehensive Transplant Center, Johns Hopkins University School of Medicine, Baltimore, MD
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Lindsay Barker
- Comprehensive Transplant Center, Johns Hopkins University School of Medicine, Baltimore, MD
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Julie Langlee
- Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD
- Comprehensive Transplant Center, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Kristin Freed
- Comprehensive Transplant Center, Johns Hopkins University School of Medicine, Baltimore, MD
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Lauren Boyer
- Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD
- Comprehensive Transplant Center, Johns Hopkins University School of Medicine, Baltimore, MD
| | - R. Scott Anderson
- Comprehensive Transplant Center, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Maura Belden
- Comprehensive Transplant Center, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Jaclyn Bannon
- Comprehensive Transplant Center, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Olivia S. Kates
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Nitipong Permpalung
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Heba Mostafa
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Dorry L. Segev
- Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Daniel C. Brennan
- Comprehensive Transplant Center, Johns Hopkins University School of Medicine, Baltimore, MD
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Robin K. Avery
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD
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Butterfield BJ, Holmgren CA, Anderson RS, Betancourt JL. Life history traits predict colonization and extinction lags of desert plant species since the Last Glacial Maximum. Ecology 2019; 100:e02817. [PMID: 31291688 DOI: 10.1002/ecy.2817] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 07/25/2019] [Accepted: 06/13/2019] [Indexed: 11/11/2022]
Abstract
Variation in life-history strategies can affect metapopulation dynamics and consequently the composition and diversity of communities. However, data sets that allow for the full range of species turnover from colonization to extinction over relevant time periods are limited. The late Quaternary record provides unique opportunities to explore the traits that may have influenced interspecific variation in responses to past climate warming, in particular the rate at which species colonized newly suitable habitat or went locally extinct from degrading habitat. We controlled for differences in species climate niches in order to predict expected colonization and extinction sequences recorded in packrat middens from 15 localities in the Mohave, Sonoran, and Chihuahuan deserts of North America. After accounting for temperature niche differences, we tested the hypotheses that dispersal syndrome (none, wind, vertebrate), growth form (herb, shrub, tree) and seed mass mediated variation in postglacial colonization lags among species, whereas clonality (clonal, non-clonal), growth form, and seed mass affected extinction lags. Growth form and dispersal syndrome interactively affected colonization lags, where herbaceous species lacking long-distance dispersal mechanisms exhibited lags that exceeded those of woody, wind or vertebrate-dispersed species by an average of 2,000-5,000 yr. Growth form and seed mass interactively affected extinction lags, with very small-seeded shrubs persisting for 4,000-8,000 yr longer than other functional groups. Taller, vertebrate-dispersed plants have been shown in other studies to disperse farther than shorter plants without specialized dispersal mechanisms. We found that variation along this axis of dispersal syndromes resulted in dramatic differences in colonization rates in response to past climate change. Very small seeded shrubs may have a unique combination of long vegetative and seed bank lifetimes that may allow them to persist for long periods despite declines in habitat condition. This study indicates that readily measurable traits may help predict which species will be more or less sensitive to future climate change, and inform interventions that can stabilize and promote at-risk populations.
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Affiliation(s)
- Bradley J Butterfield
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, 86011, USA
| | - Camille A Holmgren
- Geography and Planning Department, State University of New York College at Buffalo, Buffalo, New York, 14222, USA
| | - R Scott Anderson
- School of Earth and Sustainability, Northern Arizona University, Flagstaff, Arizona, 86011, USA
| | - Julio L Betancourt
- Science and Decisions Center, U.S. Geological Survey, Reston, Virginia, 20192, USA.,Earth System Science Interdisciplinary Center, University of Maryland, College Park, Maryland, 20740, USA
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Hardiman M, Scott AC, Pinter N, Anderson RS, Ejarque A, Carter-Champion A, Staff RA. Fire history on the California Channel Islands spanning human arrival in the Americas. Philos Trans R Soc Lond B Biol Sci 2017; 371:rstb.2015.0167. [PMID: 27216524 DOI: 10.1098/rstb.2015.0167] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/29/2016] [Indexed: 11/12/2022] Open
Abstract
Recent studies have suggested that the first arrival of humans in the Americas during the end of the last Ice Age is associated with marked anthropogenic influences on landscape; in particular, with the use of fire which, would have given even small populations the ability to have broad impacts on the landscape. Understanding the impact of these early people is complicated by the dramatic changes in climate occurring with the shift from glacial to interglacial conditions. Despite these difficulties, we here attempt to test the extent of anthropogenic influence using the California Channel Islands as a smaller, landscape-scale test bed. These islands are famous for the discovery of the 'Arlington Springs Man', which are some of the earliest human remains in the Americas. A unifying sedimentary charcoal record is presented from Arlington Canyon, Santa Rosa Island, based on over 20 detailed sedimentary sections from eight key localities. Radiocarbon dating was based on thin, fragile, long fragments of charcoal in order to avoid the 'inbuilt' age problem. Radiocarbon dating of 49 such fragments has allowed inferences regarding the fire and landscape history of the Canyon ca 19-11 ka BP. A significant period of charcoal deposition is identified approximately 14-12.5 ka BP and bears remarkable closeness to an estimated age range of the first human arrival on the islands.This article is part of the themed issue 'The interaction of fire and mankind'.
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Affiliation(s)
- Mark Hardiman
- Department of Geography, University of Portsmouth, Portsmouth, Hampshire, UK
| | - Andrew C Scott
- Department of Earth Sciences, Royal Holloway, University of London, Egham, Surrey, UK
| | - Nicholas Pinter
- Department of Earth and Planetary Sciences, University of California Davis, Davis, CA, USA
| | - R Scott Anderson
- School of Earth Sciences and Environmental Sustainability, Northern Arizona University, Flagstaff, AZ, USA
| | - Ana Ejarque
- UMR 6042, GEOLAB, CNRS, 4 rue Ledru, 63057 Clermont-Ferrand cedex 1, France GEOLAB, Université Clermont Auvergne, Université Blaise Pascal, BP 10448, 63000 Clermont-Ferrand, France
| | | | - Richard A Staff
- Oxford Radiocarbon Accelerator Unit (ORAU), Research Laboratory for Archaeology and the History of Art (RLAHA), University of Oxford, Dyson Perrins Building, South Parks Road, Oxford, UK
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García-Alix A, Jiménez-Espejo FJ, Toney JL, Jiménez-Moreno G, Ramos-Román MJ, Anderson RS, Ruano P, Queralt I, Delgado Huertas A, Kuroda J. Alpine bogs of southern Spain show human-induced environmental change superimposed on long-term natural variations. Sci Rep 2017; 7:7439. [PMID: 28785039 PMCID: PMC5547100 DOI: 10.1038/s41598-017-07854-w] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [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: 10/05/2016] [Accepted: 07/05/2017] [Indexed: 11/09/2022] Open
Abstract
Recent studies have proved that high elevation environments, especially remote wetlands, are exceptional ecological sensors of global change. For example, European glaciers have retreated during the 20th century while the Sierra Nevada National Park in southern Spain witnessed the first complete disappearance of modern glaciers in Europe. Given that the effects of climatic fluctuations on local ecosystems are complex in these sensitive alpine areas, it is crucial to identify their long-term natural trends, ecological thresholds, and responses to human impact. In this study, the geochemical records from two adjacent alpine bogs in the protected Sierra Nevada National Park reveal different sensitivities and long-term environmental responses, despite similar natural forcings, such as solar radiation and the North Atlantic Oscillation, during the late Holocene. After the Industrial Revolution both bogs registered an independent, abrupt and enhanced response to the anthropogenic forcing, at the same time that the last glaciers disappeared. The different response recorded at each site suggests that the National Park and land managers of similar regions need to consider landscape and environmental evolution in addition to changing climate to fully understand implications of climate and human influence.
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Affiliation(s)
- Antonio García-Alix
- School of Geographical and Earth Sciences, University of Glasgow, Glasgow, UK. .,Departamento de Estratigrafía y Paleontología, Universidad de Granada, Granada, Spain.
| | | | - Jaime L Toney
- School of Geographical and Earth Sciences, University of Glasgow, Glasgow, UK
| | | | - María J Ramos-Román
- Departamento de Estratigrafía y Paleontología, Universidad de Granada, Granada, Spain
| | - R Scott Anderson
- School of Earth Sciences and Environmental Sustainability, Northern Arizona University, Flagstaff, AZ, USA
| | - Patricia Ruano
- Departamento de Geodinámica, Universidad de Granada, Granada, Spain.,Instituto Andaluz de Ciencias de la Tierra (IACT), CISC-UGR, Armilla, Spain
| | - Ignasi Queralt
- Institute of Environmental Assessment and Water Research (IDAEA), CSIC, Barcelona, Spain
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Rick TC, Sillett TS, Ghalambor CK, Hofman CA, Ralls K, Anderson RS, Boser CL, Braje TJ, Cayan DR, Chesser RT, Collins PW, Erlandson JM, Faulkner KR, Fleischer R, Funk WC, Galipeau R, Huston A, King J, Laughrin L, Maldonado J, McEachern K, Muhs DR, Newsome SD, Reeder-Myers L, Still C, Morrison SA. Ecological Change on California's Channel Islands from the Pleistocene to the Anthropocene. Bioscience 2014. [DOI: 10.1093/biosci/biu094] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Anderson RS. You have a voice in Mississippi medicine; attend the annual session in Jackson. J Miss State Med Assoc 2014; 55:243; discussion 243. [PMID: 25252430] [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: 06/03/2023]
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Anderson RS. Vegetarian hunting in Garlandsville, Mississippi. J Miss State Med Assoc 2014; 55:67-68. [PMID: 25771618] [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: 06/04/2023]
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García-Alix A, Jimenez-Espejo FJ, Lozano JA, Jiménez-Moreno G, Martinez-Ruiz F, García Sanjuán L, Aranda Jiménez G, García Alfonso E, Ruiz-Puertas G, Anderson RS. Anthropogenic impact and lead pollution throughout the Holocene in Southern Iberia. Sci Total Environ 2013; 449:451-60. [PMID: 23454707 DOI: 10.1016/j.scitotenv.2013.01.081] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 01/15/2013] [Accepted: 01/17/2013] [Indexed: 05/04/2023]
Abstract
Present day lead pollution is an environmental hazard of global proportions. A correct determination of natural lead levels is very important in order to evaluate anthropogenic lead contributions. In this paper, the anthropogenic signature of early metallurgy in Southern Iberia during the Holocene, more specifically during the Late Prehistory, was assessed by mean of a multiproxy approach: comparison of atmospheric lead pollution, fire regimes, deforestation, mass sediment transport, and archeological data. Although the onset of metallurgy in Southern Iberia is a matter of controversy, here we show the oldest lead pollution record from Western Europe in a continuous paleoenvironmental sequence, which suggests clear lead pollution caused by metallurgical activities since ~3900 cal BP (Early Bronze Age). This lead pollution was especially important during Late Bronze and Early Iron ages. At the same time, since ~4000 cal BP, an increase in fire activity is observed in this area, which is also coupled with deforestation and increased erosion rates. This study also shows that the lead pollution record locally reached near present-day values many times in the past, suggesting intensive use and manipulation of lead during those periods in this area.
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Affiliation(s)
- A García-Alix
- Instituto Andaluz de Ciencias de la Tierra (IACT-CSIC-UGR), Consejo Superior de Investigaciones Científicas-Universidad de Granada, Avenida de las Palmeras no 4, 18100 Granada, Spain.
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Anderson RS. Doctors and magic. J Miss State Med Assoc 2012; 53:350. [PMID: 23210235] [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: 06/01/2023]
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Anderson RS. Supralumenal neutrinos and "the god particle"--a CERN update. J Miss State Med Assoc 2012; 53:97. [PMID: 22712182] [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: 06/01/2023]
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Anderson RS. The future of books. J Miss State Med Assoc 2011; 52:335. [PMID: 22268259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
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Fawcett PJ, Werne JP, Anderson RS, Heikoop JM, Brown ET, Berke MA, Smith SJ, Goff F, Donohoo-Hurley L, Cisneros-Dozal LM, Schouten S, Sinninghe Damsté JS, Huang Y, Toney J, Fessenden J, WoldeGabriel G, Atudorei V, Geissman JW, Allen CD. Erratum: Extended megadroughts in the southwestern United States during Pleistocene interglacials. Nature 2011. [DOI: 10.1038/nature09949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Anderson RS. Do not spill up nose!!! J Miss State Med Assoc 2011; 52:139-140. [PMID: 21678860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
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Anderson RS. Hard. J Miss State Med Assoc 2010; 51:374-375. [PMID: 21370611] [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: 05/30/2023]
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Anderson RS. The loss of magic. J Miss State Med Assoc 2010; 51:341-342. [PMID: 21365970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
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Anderson RS. Boils and goiters. J Miss State Med Assoc 2010; 51:278-279. [PMID: 21361093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
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Anderson RS. Evidence based. J Miss State Med Assoc 2010; 51:238-239. [PMID: 21365988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
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Abstract
Saltation is important in the transport of sand-sized granular material by wind and in the ejection of dust from the bed both on Earth and on Mars. The evolution of the saltating population and all its characteristic profiles is calculated from inception by pure aerodynamic entrainment through to steady state. Results of numerical simulations of single-grain impacts into granular beds are condensed into analytic expressions for the number and speeds of grains rebounding or rejected (splashed) from the bed. A model is combined with (i) this numerical representation, (ii) an expression for the aerodynamic entrainment rate, and (iii) the modification of the wind velocity profile by saltating grains. Calculated steady state mass fluxes are within the range of mass fluxes measured in wind tunnel experiments; mass flux is nonlinearly dependent on the shear velocity. Aerodynamically entrained grains in the system are primarily seeding agents; at steady state, aerodynamic entrainment is rare. The time for the entire system to reach steady state is roughly 1 second, or several long-trajectory hop times.
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Friedewald WF, Anderson RS. INFLUENCE OF EXTRANEOUS PROTEIN AND VIRUS CONCENTRATION ON THE INACTIVATION OF THE RABBIT PAPILLOMA VIRUS BY X-RAYS. ACTA ACUST UNITED AC 2010; 74:463-87. [PMID: 19871148 PMCID: PMC2135197 DOI: 10.1084/jem.74.5.463] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
The pronounced resistance to the x-rays manifested by the papilloma virus in ordinary suspensions is due to the protecting influence of extraneous matter and also in considerable degree to the amount of virus present in the preparation. Two to 4 million r were required to inactivate the virus contained in the crude papilloma extracts prepared for the present work, whereas 100,000 r or less was enough to inactivate comparable concentrations of virus after extraneous matter had been excluded by repeated differential centrifugation. The addition of normal rabbit serum or crystalline egg albumin to purified suspensions of virus was found to increase greatly the amount of irradiation required to inactivate the virus. Furthermore the percentage destruction of virus by a given amount of irradiation increases as the concentration is decreased by dilution with saline or buffer solutions. As little as 3,000 r will inactivate much of the virus in very dilute suspensions. The complement-binding antigen of papilloma virus suspensions is also inactivated by x-rays, but requires a somewhat larger amount of irradiation than necessary to destroy the infectivity of the suspensions. The effects of irradiation on the antiviral antibody present in the blood of animals which have become immune to the virus—an antibody that specifically fixes complement in mixture with the papilloma virus—are also conditioned by extraneous material. 250,000 to 500,000 r had only a slight effect on the antibody in whole serum, while this amount of irradiation completely inactivated comparable amounts of antibody in preparations partially purified by precipitation with ammonium sulfate. As a whole the findings indicate that under certain conditions of purity and concentration most of the radiation does not act by direct hits on virus or antibody particles, but indirectly by ionizing or exciting some other molecules present in the exposed suspension, which then react with the virus or antibody molecules.
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Affiliation(s)
- W F Friedewald
- Laboratories of The Rockefeller Institute for Medical Research and Memorial Hospital, New York
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Friedewald WF, Anderson RS. THE EFFECTS OF ROENTGEN RAYS ON CELL-VIRUS ASSOCIATIONS : FINDINGS WITH VIRUS-INDUCED RABBIT PAPILLOMAS AND FIBROMAS. ACTA ACUST UNITED AC 2010; 78:285-304. [PMID: 19871328 PMCID: PMC2135399 DOI: 10.1084/jem.78.4.285] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The virus-induced papillomas of cottontail as well as domestic rabbits regress completely within a few weeks when exposed to 5,000 r of x-ray irradiation. The x-rays do not immediately kill the papilloma cells, but lead to death by inhibiting cellular division and producing pathological changes in the cells which then continue to differentiate. The virus associated with the growths, however, not only persists in undiminished amount during regression, but often an increased yield of it can be obtained on extraction. The fibroma virus in crude extracts or in vivo is inactivated by far less irradiation than the papilloma virus. 10,000 r destroys 90 per cent or more of the infectivity of the fibroma virus, whereas at least 100,000 r is required to inactivate 50 per cent of the papilloma virus in extracts containing about the same amount of protein. No variant of the papilloma virus or fibroma virus has been encountered as a result of the irradiation.
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Affiliation(s)
- W F Friedewald
- Laboratories of The Rockefeller Institute for Medical Research and Memorial Hospital, New York
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Abstract
1. When normal, monodisperse hemocyanin (60.5S) from Limulus Rolyphemus was irradiated in neutral buffer with x-rays, several new, more rapidly sedimenting ultracentrifugal components (86S, 107S, 122S) were produced, with a corresponding loss in the amount of the unaffected protein. The amount of the effect was roughly proportional to the amount of irradiation. 2. The new resolvable components apparently represented an association of the primary particles into aggregates of 2, 3, and 4 primary particles respectively. 3. The proportional amount of hemocyanin affected decreased almost to the vanishing point as the concentration of the protein was raised to high levels. 4. The absolute effect, i.e. the total number of particles affected in a given volume, increased with the concentration of hemocyanin, at least for concentrations below 15 per cent. 5. The presence of 33 per cent horse serum during irradiation inhibited the effect on the hemocyanin almost completely, with hemocyanin concentrations of both 0.8 and 14 per cent. 6. The presence of 2.8 per cent egg albumin during irradiation lowered the effect by about 70 per cent in the case of dilute preparations (0.8 per cent hemocyanin), but by only about 25 per cent in the case of 14 per cent solutions. 7. A lowering of the solution's oxygen tension during irradiation enhanced the effect, almost doubling it in some cases. 8. The probable theoretical significance of these and other observations are discussed in the text.
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Affiliation(s)
- E G Pickels
- Laboratories of the International Health Division of The Rockefeller Foundation, New York, the Department of Physiology, School of Medicine, University of Maryland, Baltimore, and the Memorial Hospital, New York
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Abstract
Some solubility, oxidation, reduction, and compound-forming characteristics of extracts of Cypridina luciferin have been presented. A method of purification has been described which increased the amount of luciferin per unit of dry weight, as measured by the total light emitted, to about two thousand times that in the dry starting material. The best yields were from 50 to 65 per cent.
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Affiliation(s)
- R S Anderson
- Physiological Laboratory, Princeton University, Princeton, N. J
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Anderson RS, Harrison B. THE QUANTITATIVE EFFECT OF X-RAYS ON ASCORBIC ACID IN SIMPLE SOLUTION AND IN MIXTURES OF NATURALLY OCCURRING COMPOUNDS. ACTA ACUST UNITED AC 2010; 27:69-75. [PMID: 19873377 PMCID: PMC2142589 DOI: 10.1085/jgp.27.2.69] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Data on the x-ray induced reaction of ascorbic acid in simple inorganic solution, in solutions containing serum albumin, in plasma, and in muscle have been presented. The reaction occurred in the presence of serum albumin and in human plasma but was relatively small in excised rat muscle.
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Anderson RS. Eavesdropping. J Miss State Med Assoc 2010; 51:63-64. [PMID: 20827874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
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Anderson RS. Canine behavior. J Miss State Med Assoc 2010; 51:31-32. [PMID: 20827869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
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Anderson RS. The uncommon thread. J Miss State Med Assoc 2009; 50:438-439. [PMID: 20830874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
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Anderson RS. Where I fit in the food chain. J Miss State Med Assoc 2009; 50:67-68. [PMID: 19297950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
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Anderson RS. Risks. J Miss State Med Assoc 2008; 49:385-386. [PMID: 19297935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
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King RP, Anderson RS, Kandagatla KK. Comment on “Quantifying the interplay effect in prostate IMRT delivery using a convolution-based method” [Med. Phys., - (2008)]. Med Phys 2008; 35:5955-6. [DOI: 10.1118/1.3013551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Anderson RS. The faith of the moneychangers. J Miss State Med Assoc 2008; 49:355-356. [PMID: 19297930] [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: 05/27/2023]
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Wolsley CJ, Silvestri G, O'Neill J, Saunders KJ, Anderson RS. The association between multifocal electroretinograms and OCT retinal thickness in retinitis pigmentosa patients with good visual acuity. Eye (Lond) 2008; 23:1524-31. [PMID: 18978727 DOI: 10.1038/eye.2008.318] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
AIMS To investigate relationships between retinal morphology and retinal function in patients with retinitis pigmentosa (RP) using optical coherence tomography (OCT) and multifocal electroretinography (mfERG). METHODS In all, 14 patients with RP who had visual acuities of 0.2 logMAR or better and Humphrey central fields of 10 degrees or larger participated in the study along with 16 normal control subjects. The amplitudes and timings of the mfERG responses were compared with spatially corresponding measures of retinal layer thickness from OCT within the macula region (central 12 degrees ). RESULTS Eyes with RP showed thinning of the photoreceptor retinal (PR) layer and thickening of mid-inner retinal (MIR) layers beyond the fovea. mfERG amplitude was reduced in all regions, whereas mfERG timing was only significantly delayed at a retinal eccentricity of 6-12 degrees and was otherwise preserved within the foveal and parafoveal retina (0-6 degrees). PR layer thickness was correlated with mfERG amplitude across the macula region. mfERG timing was correlated with the total change in retinal thickness (combined PR thinning and MIR thickening) at an eccentricity of 6-12 degrees. CONCLUSIONS The relationship between mfERG timing and retinal thickness in RP is dependent on the retinal eccentricity. Preserved timing in the central retina (0-6 degrees ), despite significant disruption to retinal laminar structure, could be suggestive of inner retinal remodelling or functional redundancy. Cone system activity derived from mfERG amplitude appears to be related to the thickness of the photoreceptor layer in the macula region.
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Affiliation(s)
- C J Wolsley
- Vision Science Research Group, Department of Optometry, University of Ulster, Coleraine, UK.
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Anderson RS. Confabulation nation. J Miss State Med Assoc 2008; 49:259-260. [PMID: 19295049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
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Anderson RS. In response to: "Has our MSMA been hijacked?". J Miss State Med Assoc 2008; 49:220. [PMID: 19297914] [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: 05/27/2023]
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Anderson RS. SGR, GDP, and CRAP. J Miss State Med Assoc 2008; 49:195-196. [PMID: 19295044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
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Scott Anderson R, Smith SJ, Jass RB, Geoffrey Spaulding W. A Late Holocene Record of Vegetation and Climate from a Small Wetland in Shasta County, California. ACTA ACUST UNITED AC 2008. [DOI: 10.3120/0024-9637(2008)55[15:alhrov]2.0.co;2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Anderson RS. Eggs, beaches and shotguns. J Miss State Med Assoc 2007; 48:359-360. [PMID: 19292136] [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: 05/27/2023]
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Anderson RS. Stuff that wears you out. J Miss State Med Assoc 2007; 48:327-328. [PMID: 19292130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
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King RP, Anderson RS, Kandagatla KK. Comment on “IMRT should not be administered at photon energies greater than 10MV” [Med. Phys., - (2007)]. Med Phys 2007; 34:3696. [DOI: 10.1118/1.2767971] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Anderson RS. Saving lives-more. J Miss State Med Assoc 2007; 48:263-264. [PMID: 17944083] [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: 05/25/2023]
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Anderson RS. Saving lives. J Miss State Med Assoc 2007; 48:199-200. [PMID: 17941248] [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: 05/25/2023]
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Hogg RE, Zlatkova MB, Chakravarthy U, Anderson RS. Investigation of the effect of simulated lens yellowing, transparency loss and refractive error on in vivo resonance Raman spectroscopy. Ophthalmic Physiol Opt 2007; 27:225-31. [PMID: 17470234 DOI: 10.1111/j.1475-1313.2007.00478.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [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: 11/30/2022]
Abstract
PURPOSE To separately investigate the impact of simulated age-related lens yellowing, transparency loss and refractive error on measurements of macular pigment (MP) using resonance Raman spectroscopy. METHODS Two healthy young subjects with clear media underwent Raman spectroscopy under the following conditions: age-related lens yellowing was simulated using seven broad-band yellow filters with transmittance at 488 nm ranging from 0.54 to 0.90; cataract was simulated using five white filters of increasing opacity (scatter filters), the transmittance of which ranged from 0.42 to 0.86, each of which reduced peak contrast sensitivity by approximately 0.1 log units over the previous filter. Refractive error up to +6.25 D was achieved using soft contact lenses. RESULTS The Raman signal declined steadily to an average value of 43% of the starting value with the densest yellow filter in place. The white scatter filters produced a progressive linear reduction in signal resulting in almost complete signal loss with the densest filter. Refractive error resulted in an initial slight improvement in Raman count up to a value of +2.00 D followed by a decline thereafter. CONCLUSIONS These results imply that lens yellowing and increasing scatter has an influence on the Raman signal and suggest that studies using this technology to estimate MP levels in older populations should carefully account for the status of the lens.
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Affiliation(s)
- R E Hogg
- Department of Ophthalmology and Vision Science, Queen's University, Belfast, UK.
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Anderson RS. Subject: the AMA--should MSMA remain unified or deunify? Benefits of remaining unified with the AMA. J Miss State Med Assoc 2007; 48:111-112. [PMID: 17941259] [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: 05/25/2023]
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Treloar EJ, Anderson RS, Andrews HS, Bailey JL. Authors response to: Uterine necrosis following B-Lynch suture for primary postpartum haemorrhage. BJOG 2006. [DOI: 10.1111/j.1471-0528.2006.01093.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Hogg RE, Anderson RS, Stevenson MR, Zlatkova MB, Chakravarthy U. In vivo macular pigment measurements: a comparison of resonance Raman spectroscopy and heterochromatic flicker photometry. Br J Ophthalmol 2006; 91:485-90. [PMID: 16825281 PMCID: PMC1994744 DOI: 10.1136/bjo.2006.090936] [Citation(s) in RCA: 19] [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: 11/04/2022]
Abstract
AIM To investigate whether two methods of measuring macular pigment-namely, heterochromatic flicker photometry (HFP) and resonance Raman spectroscopy (RRS)--yield comparable data. METHODS Macular pigment was measured using HFP and RRS in the right eye of 107 participants aged 20-79 years. Correlations between methods were sought and regression models generated. RRS was recorded as Raman counts and HFP as macular pigment optical density (MPOD). The average of the top three of five Raman counts was compared with MPOD obtained at 0.5 degrees eccentricity, and an integrated measure (spatial profile; MPODsp) computed from four stimulus sizes on HFP. RESULTS The coefficient of variation was 12.0% for MPODsp and 13.5% for Raman counts. MPODsp exhibited significant correlations with Raman counts (r = 0.260, p = 0.012), whereas MPOD at 0.5 degrees did not correlate significantly (r = 0.163, p = 0.118). MPODsp was not significantly correlated with age (p = 0.062), whereas MPOD at 0.5 degrees was positively correlated (p = 0.011). Raman counts showed a significant decrease with age (p = 0.002) and were significantly lower when pupil size was smaller (p = 0.015). CONCLUSIONS Despite a statistically significant correlation, the correlations were weak, with those in excess of 90% of the variance between MPODsp and Raman counts remaining unexplained, meriting further research.
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Affiliation(s)
- R E Hogg
- Department of Ophthalmology, Queen's University Belfast BT12 6BA, UK.
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Affiliation(s)
- E J Treloar
- Women and Children's Health, Southmead Hospital, Bristol, UK
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