9 results
Characterization of English and Spanish language proficiency among middle school English learners with reading difficulties
- Kelly T. Macdonald, David J. Francis, Arturo E. Hernandez, Anny P. Castilla-Earls, Paul T. Cirino
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- Journal:
- Bilingualism: Language and Cognition / Volume 25 / Issue 5 / November 2022
- Published online by Cambridge University Press:
- 08 March 2022, pp. 899-912
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Among bilinguals, language-related variables such as first and second language proficiency and balance may be related to important cognitive and academic outcomes, but approaches to characterizing these variables are inconsistent, particularly among at-risk samples of children. The current study employed comprehensive language assessment of English and Spanish language skills and contrasted various approaches to the characterization of language among at-risk ELs in middle school (N = 161). Specifically, we contrasted variable-centered and person-centered approaches, and convergence between objective and self-report measures. Findings support a two-factor structure of English and Spanish language skills in this population, three profiles of students (balanced, moderately unbalanced-higher Spanish, and very unbalanced-higher English), convergence between variable-centered and person-centered approaches, and mixed support for subjective indices of usage. Results provide a foundation from which to examine the roles of L1 and L2 proficiency as well as balance in important cognitive and academic outcomes in this at-risk and understudied population.
Hope in Dirt: Report of the Fort Apache Workshop on Forensic Sedimentology Applications to Cultural Property Crime, 15—19 October 2018
- John R. Welch, Mark T. Altaha, Garry J. Cantley, William H. Doelle, Sarah A. Herr, Morag M. Kersel, Brandi L. MacDonald, Francis P. McManamon, Barbara Mills, Fred Nials, Mary Ownby, Michael Richards, Ramon Riley, Stacy L. Ryan, Duston Whiting, Donna Yates
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- Journal:
- International Journal of Cultural Property / Volume 26 / Issue 2 / May 2019
- Published online by Cambridge University Press:
- 20 August 2019, pp. 197-210
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A 2018 workshop on the White Mountain Apache Tribe lands in Arizona examined ways to enhance investigations into cultural property crime (CPC) through applications of rapidly evolving methods from archaeological science. CPC (also looting, graverobbing) refers to unauthorized damage, removal, or trafficking in materials possessing blends of communal, aesthetic, and scientific values. The Fort Apache workshop integrated four generally partitioned domains of CPC expertise: (1) theories of perpetrators’ motivations and methods; (2) recommended practice in sustaining public and community opposition to CPC; (3) tactics and strategies for documenting, investigating, and prosecuting CPC; and (4) forensic sedimentology—uses of biophysical sciences to link sediments from implicated persons and objects to crime scenes. Forensic sedimentology served as the touchstone for dialogues among experts in criminology, archaeological sciences, law enforcement, and heritage stewardship. Field visits to CPC crime scenes and workshop deliberations identified pathways toward integrating CPC theory and practice with forensic sedimentology’s potent battery of analytic methods.
Trace Fossils with Spreiten from the Late Ediacaran Nama Group, Namibia: Complex Feeding Patterns Five Million Years Before the Precambrian–Cambrian Boundary
- Francis A. Macdonald, Sara B. Pruss, Justin V. Strauss
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- Journal:
- Journal of Paleontology / Volume 88 / Issue 2 / March 2014
- Published online by Cambridge University Press:
- 15 October 2015, pp. 299-308
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Here we describe large, complex trace fossils in the late Ediacaran Omkyk Member of the Zaris Formation, Nama Group, southern Namibia. The horizontal trace fossils are preserved on a number of talus blocks from a bedding plane of a cm-thick sandstone lens from a single stratigraphic horizon less than 100 m below an ash bed dated at 547.3 ± 0.7 Ma. The forms consist of overlapping U-shaped spreiten elements with parallel limbs surrounded by an outer tube. Individual U-shaped elements are 0.2 to 1 cm in diameter, the outer tube is less than 3 mm in diameter, and the forms as a whole range from 5 to 30 cm long and 3 to 10 cm wide. The specimens commonly show a change in direction and change in diameter. The morphology of these trace fossils is comparable to backfill structures, particularly specimens of Paleozoic Zoophycos from shallow water environments. Here we interpret these horizontal spreiten-burrows to record the grazing of the trace-maker on or below a textured organic surface. The identification of large late Ediacaran trace fossils is consistent with recent reports of backfilled horizontal burrows below the Precambrian–Cambrian boundary and is suggestive of the appearance of complex feeding habits prior to the Cambrian trace fossil explosion.
The Proterozoic Record of Eukaryotes
- Phoebe A. Cohen, Francis A. Macdonald
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- Journal:
- Paleobiology / Volume 41 / Issue 4 / September 2015
- Published online by Cambridge University Press:
- 10 September 2015, pp. 610-632
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Proterozoic strata host evidence of global “Snowball Earth” glaciations, large perturbations to the carbon cycle, proposed changes in the redox state of oceans, the diversification of microscopic eukaryotes, and the rise of metazoans. Over the past half century, the number of fossils described from Proterozoic rocks has increased exponentially. These discoveries have occurred alongside an increased understanding of the Proterozoic Earth system and the geological context of fossil occurrences, including improved age constraints. However, the evaluation of relationships between Proterozoic environmental change and fossil diversity has been hampered by several factors, particularly lithological and taphonomic biases. Here we compile and analyze the current record of eukaryotic fossils in Proterozoic strata to assess the effect of biases and better constrain diversity through time. Our results show that mean within assemblage diversity increases through the Proterozoic Eon due to an increase in high diversity assemblages, and that this trend is robust to various external factors including lithology and paleogeographic location. In addition, assemblage composition changes dramatically through time. Most notably, robust recalcitrant taxa appear in the early Neoproterozoic Era, only to disappear by the beginning of the Ediacaran Period. Within assemblage diversity is significantly lower in the Cryogenian Period than in the preceding and following intervals, but the short duration of the nonglacial interlude and unusual depositional conditions may present additional biases. In general, large scale patterns of diversity are robust while smaller scale patterns are difficult to discern through the lens of lithological, taphonomic, and geographic variability.
New Ediacaran fossils from the uppermost Blueflower Formation, northwest Canada: disentangling biostratigraphy and paleoecology
- Calla A. Carbone, Guy M. Narbonne, Francis A. Macdonald, Thomas H. Boag
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- Journal:
- Journal of Paleontology / Volume 89 / Issue 2 / March 2015
- Published online by Cambridge University Press:
- 04 June 2015, pp. 281-291
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New Ediacaran fossil finds at Sekwi Brook occur in lower shoreface to offshore transition beds at the top of the Blueflower Formation, which are the most shallow-water facies and the youngest strata in which Ediacara-type fossils have been described from the Mackenzie Mountains of NW Canada. Newly discovered Ediacaran body fossils include two new tubular genera: Sekwitubulus annulatus new genus new species was a mm-diameter rigid annulated tube that was rooted to the sea bottom by a holdfast; Annulatubus flexuosus n. gen. n. sp. was a cm-diameter, flexible annulated tube. In conjunction with previously described large attachment discs representing the form-genus Aspidella and a single specimen of the dickinsonid Windermeria, these fossils define an assemblage that differs markedly from the rangeomorph-dominated deeper-water and older assemblages lower in the same section at Sekwi Brook. In contrast, trace fossils show little change upwards through the Blueflower Formation, at least in part reflecting their origin by microbial grazers on mats that formed during low-energy periods in both deep- and shallow-water environments. This implies that the stratigraphic succession of Ediacaran fossils in NW Canada and probably globally represents both evolutionary changes with age and the paleoecology of specific depositional settings.
Contributors
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- By Mitchell Aboulafia, Frederick Adams, Marilyn McCord Adams, Robert M. Adams, Laird Addis, James W. Allard, David Allison, William P. Alston, Karl Ameriks, C. Anthony Anderson, David Leech Anderson, Lanier Anderson, Roger Ariew, David Armstrong, Denis G. Arnold, E. J. Ashworth, Margaret Atherton, Robin Attfield, Bruce Aune, Edward Wilson Averill, Jody Azzouni, Kent Bach, Andrew Bailey, Lynne Rudder Baker, Thomas R. Baldwin, Jon Barwise, George Bealer, William Bechtel, Lawrence C. Becker, Mark A. Bedau, Ernst Behler, José A. Benardete, Ermanno Bencivenga, Jan Berg, Michael Bergmann, Robert L. Bernasconi, Sven Bernecker, Bernard Berofsky, Rod Bertolet, Charles J. Beyer, Christian Beyer, Joseph Bien, Joseph Bien, Peg Birmingham, Ivan Boh, James Bohman, Daniel Bonevac, Laurence BonJour, William J. Bouwsma, Raymond D. Bradley, Myles Brand, Richard B. Brandt, Michael E. Bratman, Stephen E. Braude, Daniel Breazeale, Angela Breitenbach, Jason Bridges, David O. Brink, Gordon G. Brittan, Justin Broackes, Dan W. Brock, Aaron Bronfman, Jeffrey E. Brower, Bartosz Brozek, Anthony Brueckner, Jeffrey Bub, Lara Buchak, Otavio Bueno, Ann E. Bumpus, Robert W. Burch, John Burgess, Arthur W. Burks, Panayot Butchvarov, Robert E. Butts, Marina Bykova, Patrick Byrne, David Carr, Noël Carroll, Edward S. Casey, Victor Caston, Victor Caston, Albert Casullo, Robert L. Causey, Alan K. L. Chan, Ruth Chang, Deen K. Chatterjee, Andrew Chignell, Roderick M. Chisholm, Kelly J. Clark, E. J. Coffman, Robin Collins, Brian P. Copenhaver, John Corcoran, John Cottingham, Roger Crisp, Frederick J. Crosson, Antonio S. Cua, Phillip D. Cummins, Martin Curd, Adam Cureton, Andrew Cutrofello, Stephen Darwall, Paul Sheldon Davies, Wayne A. Davis, Timothy Joseph Day, Claudio de Almeida, Mario De Caro, Mario De Caro, John Deigh, C. F. Delaney, Daniel C. Dennett, Michael R. DePaul, Michael Detlefsen, Daniel Trent Devereux, Philip E. Devine, John M. Dillon, Martin C. Dillon, Robert DiSalle, Mary Domski, Alan Donagan, Paul Draper, Fred Dretske, Mircea Dumitru, Wilhelm Dupré, Gerald Dworkin, John Earman, Ellery Eells, Catherine Z. Elgin, Berent Enç, Ronald P. Endicott, Edward Erwin, John Etchemendy, C. Stephen Evans, Susan L. Feagin, Solomon Feferman, Richard Feldman, Arthur Fine, Maurice A. Finocchiaro, William FitzPatrick, Richard E. Flathman, Gvozden Flego, Richard Foley, Graeme Forbes, Rainer Forst, Malcolm R. Forster, Daniel Fouke, Patrick Francken, Samuel Freeman, Elizabeth Fricker, Miranda Fricker, Michael Friedman, Michael Fuerstein, Richard A. Fumerton, Alan Gabbey, Pieranna Garavaso, Daniel Garber, Jorge L. A. Garcia, Robert K. Garcia, Don Garrett, Philip Gasper, Gerald Gaus, Berys Gaut, Bernard Gert, Roger F. Gibson, Cody Gilmore, Carl Ginet, Alan H. Goldman, Alvin I. Goldman, Alfonso Gömez-Lobo, Lenn E. Goodman, Robert M. Gordon, Stefan Gosepath, Jorge J. E. Gracia, Daniel W. Graham, George A. Graham, Peter J. Graham, Richard E. Grandy, I. Grattan-Guinness, John Greco, Philip T. Grier, Nicholas Griffin, Nicholas Griffin, David A. Griffiths, Paul J. Griffiths, Stephen R. Grimm, Charles L. Griswold, Charles B. Guignon, Pete A. Y. Gunter, Dimitri Gutas, Gary Gutting, Paul Guyer, Kwame Gyekye, Oscar A. Haac, Raul Hakli, Raul Hakli, Michael Hallett, Edward C. Halper, Jean Hampton, R. James Hankinson, K. R. Hanley, Russell Hardin, Robert M. Harnish, William Harper, David Harrah, Kevin Hart, Ali Hasan, William Hasker, John Haugeland, Roger Hausheer, William Heald, Peter Heath, Richard Heck, John F. Heil, Vincent F. Hendricks, Stephen Hetherington, Francis Heylighen, Kathleen Marie Higgins, Risto Hilpinen, Harold T. Hodes, Joshua Hoffman, Alan Holland, Robert L. Holmes, Richard Holton, Brad W. Hooker, Terence E. Horgan, Tamara Horowitz, Paul Horwich, Vittorio Hösle, Paul Hoβfeld, Daniel Howard-Snyder, Frances Howard-Snyder, Anne Hudson, Deal W. Hudson, Carl A. Huffman, David L. Hull, Patricia Huntington, Thomas Hurka, Paul Hurley, Rosalind Hursthouse, Guillermo Hurtado, Ronald E. Hustwit, Sarah Hutton, Jonathan Jenkins Ichikawa, Harry A. Ide, David Ingram, Philip J. Ivanhoe, Alfred L. Ivry, Frank Jackson, Dale Jacquette, Joseph Jedwab, Richard Jeffrey, David Alan Johnson, Edward Johnson, Mark D. Jordan, Richard Joyce, Hwa Yol Jung, Robert Hillary Kane, Tomis Kapitan, Jacquelyn Ann K. Kegley, James A. Keller, Ralph Kennedy, Sergei Khoruzhii, Jaegwon Kim, Yersu Kim, Nathan L. King, Patricia Kitcher, Peter D. Klein, E. D. Klemke, Virginia Klenk, George L. Kline, Christian Klotz, Simo Knuuttila, Joseph J. Kockelmans, Konstantin Kolenda, Sebastian Tomasz Kołodziejczyk, Isaac Kramnick, Richard Kraut, Fred Kroon, Manfred Kuehn, Steven T. Kuhn, Henry E. Kyburg, John Lachs, Jennifer Lackey, Stephen E. Lahey, Andrea Lavazza, Thomas H. Leahey, Joo Heung Lee, Keith Lehrer, Dorothy Leland, Noah M. Lemos, Ernest LePore, Sarah-Jane Leslie, Isaac Levi, Andrew Levine, Alan E. Lewis, Daniel E. Little, Shu-hsien Liu, Shu-hsien Liu, Alan K. L. Chan, Brian Loar, Lawrence B. Lombard, John Longeway, Dominic McIver Lopes, Michael J. Loux, E. J. Lowe, Steven Luper, Eugene C. Luschei, William G. Lycan, David Lyons, David Macarthur, Danielle Macbeth, Scott MacDonald, Jacob L. Mackey, Louis H. Mackey, Penelope Mackie, Edward H. Madden, Penelope Maddy, G. B. Madison, Bernd Magnus, Pekka Mäkelä, Rudolf A. Makkreel, David Manley, William E. Mann (W.E.M.), Vladimir Marchenkov, Peter Markie, Jean-Pierre Marquis, Ausonio Marras, Mike W. Martin, A. P. Martinich, William L. McBride, David McCabe, Storrs McCall, Hugh J. McCann, Robert N. McCauley, John J. McDermott, Sarah McGrath, Ralph McInerny, Daniel J. McKaughan, Thomas McKay, Michael McKinsey, Brian P. McLaughlin, Ernan McMullin, Anthonie Meijers, Jack W. Meiland, William Jason Melanson, Alfred R. Mele, Joseph R. Mendola, Christopher Menzel, Michael J. Meyer, Christian B. Miller, David W. Miller, Peter Millican, Robert N. Minor, Phillip Mitsis, James A. Montmarquet, Michael S. Moore, Tim Moore, Benjamin Morison, Donald R. Morrison, Stephen J. Morse, Paul K. Moser, Alexander P. D. Mourelatos, Ian Mueller, James Bernard Murphy, Mark C. Murphy, Steven Nadler, Jan Narveson, Alan Nelson, Jerome Neu, Samuel Newlands, Kai Nielsen, Ilkka Niiniluoto, Carlos G. Noreña, Calvin G. Normore, David Fate Norton, Nikolaj Nottelmann, Donald Nute, David S. Oderberg, Steve Odin, Michael O’Rourke, Willard G. Oxtoby, Heinz Paetzold, George S. Pappas, Anthony J. Parel, Lydia Patton, R. P. Peerenboom, Francis Jeffry Pelletier, Adriaan T. Peperzak, Derk Pereboom, Jaroslav Peregrin, Glen Pettigrove, Philip Pettit, Edmund L. Pincoffs, Andrew Pinsent, Robert B. Pippin, Alvin Plantinga, Louis P. Pojman, Richard H. Popkin, John F. Post, Carl J. Posy, William J. Prior, Richard Purtill, Michael Quante, Philip L. Quinn, Philip L. Quinn, Elizabeth S. Radcliffe, Diana Raffman, Gerard Raulet, Stephen L. Read, Andrews Reath, Andrew Reisner, Nicholas Rescher, Henry S. Richardson, Robert C. Richardson, Thomas Ricketts, Wayne D. Riggs, Mark Roberts, Robert C. Roberts, Luke Robinson, Alexander Rosenberg, Gary Rosenkranz, Bernice Glatzer Rosenthal, Adina L. Roskies, William L. Rowe, T. M. Rudavsky, Michael Ruse, Bruce Russell, Lilly-Marlene Russow, Dan Ryder, R. M. Sainsbury, Joseph Salerno, Nathan Salmon, Wesley C. Salmon, Constantine Sandis, David H. Sanford, Marco Santambrogio, David Sapire, Ruth A. Saunders, Geoffrey Sayre-McCord, Charles Sayward, James P. Scanlan, Richard Schacht, Tamar Schapiro, Frederick F. Schmitt, Jerome B. Schneewind, Calvin O. Schrag, Alan D. Schrift, George F. Schumm, Jean-Loup Seban, David N. Sedley, Kenneth Seeskin, Krister Segerberg, Charlene Haddock Seigfried, Dennis M. Senchuk, James F. Sennett, William Lad Sessions, Stewart Shapiro, Tommie Shelby, Donald W. Sherburne, Christopher Shields, Roger A. Shiner, Sydney Shoemaker, Robert K. Shope, Kwong-loi Shun, Wilfried Sieg, A. John Simmons, Robert L. Simon, Marcus G. Singer, Georgette Sinkler, Walter Sinnott-Armstrong, Matti T. Sintonen, Lawrence Sklar, Brian Skyrms, Robert C. Sleigh, Michael Anthony Slote, Hans Sluga, Barry Smith, Michael Smith, Robin Smith, Robert Sokolowski, Robert C. Solomon, Marta Soniewicka, Philip Soper, Ernest Sosa, Nicholas Southwood, Paul Vincent Spade, T. L. S. Sprigge, Eric O. Springsted, George J. Stack, Rebecca Stangl, Jason Stanley, Florian Steinberger, Sören Stenlund, Christopher Stephens, James P. Sterba, Josef Stern, Matthias Steup, M. A. Stewart, Leopold Stubenberg, Edith Dudley Sulla, Frederick Suppe, Jere Paul Surber, David George Sussman, Sigrún Svavarsdóttir, Zeno G. Swijtink, Richard Swinburne, Charles C. Taliaferro, Robert B. Talisse, John Tasioulas, Paul Teller, Larry S. Temkin, Mark Textor, H. S. Thayer, Peter Thielke, Alan Thomas, Amie L. Thomasson, Katherine Thomson-Jones, Joshua C. Thurow, Vzalerie Tiberius, Terrence N. Tice, Paul Tidman, Mark C. Timmons, William Tolhurst, James E. Tomberlin, Rosemarie Tong, Lawrence Torcello, Kelly Trogdon, J. D. Trout, Robert E. Tully, Raimo Tuomela, John Turri, Martin M. Tweedale, Thomas Uebel, Jennifer Uleman, James Van Cleve, Harry van der Linden, Peter van Inwagen, Bryan W. Van Norden, René van Woudenberg, Donald Phillip Verene, Samantha Vice, Thomas Vinci, Donald Wayne Viney, Barbara Von Eckardt, Peter B. M. Vranas, Steven J. Wagner, William J. Wainwright, Paul E. Walker, Robert E. Wall, Craig Walton, Douglas Walton, Eric Watkins, Richard A. Watson, Michael V. Wedin, Rudolph H. Weingartner, Paul Weirich, Paul J. Weithman, Carl Wellman, Howard Wettstein, Samuel C. Wheeler, Stephen A. White, Jennifer Whiting, Edward R. Wierenga, Michael Williams, Fred Wilson, W. Kent Wilson, Kenneth P. Winkler, John F. Wippel, Jan Woleński, Allan B. Wolter, Nicholas P. Wolterstorff, Rega Wood, W. Jay Wood, Paul Woodruff, Alison Wylie, Gideon Yaffe, Takashi Yagisawa, Yutaka Yamamoto, Keith E. Yandell, Xiaomei Yang, Dean Zimmerman, Günter Zoller, Catherine Zuckert, Michael Zuckert, Jack A. Zupko (J.A.Z.)
- Edited by Robert Audi, University of Notre Dame, Indiana
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- The Cambridge Dictionary of Philosophy
- Published online:
- 05 August 2015
- Print publication:
- 27 April 2015, pp ix-xxx
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Microbial Sedimentology of Stromatolites in Neoproterozoic Cap Carbonates
- Tanja Bosak, Giulio Mariotti, Francis A. MacDonald, J. Taylor Perron, Sara B. Pruss
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- Journal:
- The Paleontological Society Papers / Volume 19 / October 2013
- Published online by Cambridge University Press:
- 21 July 2017, pp. 51-76
- Print publication:
- October 2013
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Stromatolite shapes, sizes, and spacings are products of microbial processes and interactions with topography, sedimentation, and flow. Laboratory experiments and studies of modern microbial mats and sediments can help reconstruct processes that shaped some typical stromatolite forms and some atypical microbially influenced sediments from Neoproterozoic cap carbonates. Studies of modern, cohesive microbial mats indicate that microbialaminite facies in the lower Rasthof Formation (Cryogenian) formed in the presence of very low flow and were not deformed by strong waves or currents. Giant wave ripples, corrugated stromatolites, and tube-hosting stromatolites in basal Ediacaran cap carbonates record interactions between microbes, flow, and evolving bedforms. Preferential cementation in and close to the giant ripple crests is attributed to interactions between flow and local topography. These interactions pumped alkaline porewaters into ripple crests and helped nucleate elongated stromatolites. The similar textures of giant wave ripples and elongated, corrugated, and tube-hosting stromatolites suggest growth in the presence of organic-rich, rounded particles and microbial mats, and in flow regimes that permitted mat growth. These hypotheses can be tested by experiments and models that investigate lithification and the macroscopic morphology of microbial mats as a function of the flow regime, preexisting topography, redox-stratification in sediments, and delivery of organic-rich particles. The widespread microbially influenced textures in Cryogenian microbialaminites and basal Ediacaran cap dolostones record a strong reliance of carbonate deposition on the presence of organic nuclei, supporting carbonate accumulation rates comparable to those in modern reefs. Therefore, the unusual macroscopic morphologies of microbially influenced facies in Neoproterozoic cap carbonates may not reflect oceans that were greatly oversaturated with respect to carbonate minerals.
Proceedings of the Rank Forum on Vitamin D
- S. A. Lanham-New, J. L. Buttriss, L. M. Miles, M. Ashwell, J. L. Berry, B. J. Boucher, K. D. Cashman, C. Cooper, A. L. Darling, R. M. Francis, W. D. Fraser, C. P. G. M. de Groot, E. Hyppönen, M. Kiely, C. Lamberg-Allardt, H. M. Macdonald, A. R. Martineau, T. Masud, A. Mavroeidi, C. Nowson, A. Prentice, E. M. Stone, S. Reddy, R. Vieth, C. M. Williams
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- Journal:
- British Journal of Nutrition / Volume 105 / Issue 1 / 14 January 2011
- Published online by Cambridge University Press:
- 07 December 2010, pp. 144-156
- Print publication:
- 14 January 2011
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The Rank Forum on Vitamin D was held on 2nd and 3rd July 2009 at the University of Surrey, Guildford, UK. The workshop consisted of a series of scene-setting presentations to address the current issues and challenges concerning vitamin D and health, and included an open discussion focusing on the identification of the concentrations of serum 25-hydroxyvitamin D (25(OH)D) (a marker of vitamin D status) that may be regarded as optimal, and the implications this process may have in the setting of future dietary reference values for vitamin D in the UK. The Forum was in agreement with the fact that it is desirable for all of the population to have a serum 25(OH)D concentration above 25 nmol/l, but it discussed some uncertainty about the strength of evidence for the need to aim for substantially higher concentrations (25(OH)D concentrations>75 nmol/l). Any discussion of ‘optimal’ concentration of serum 25(OH)D needs to define ‘optimal’ with care since it is important to consider the normal distribution of requirements and the vitamin D needs for a wide range of outcomes. Current UK reference values concentrate on the requirements of particular subgroups of the population; this differs from the approaches used in other European countries where a wider range of age groups tend to be covered. With the re-emergence of rickets and the public health burden of low vitamin D status being already apparent, there is a need for urgent action from policy makers and risk managers. The Forum highlighted concerns regarding the failure of implementation of existing strategies in the UK for achieving current vitamin D recommendations.
Nutrition and bone health projects funded by the UK Food Standards Agency: have they helped to inform public health policy?
- Margaret Ashwell, Elaine Stone, John Mathers, Stephen Barnes, Juliet Compston, Roger M. Francis, Tim Key, Kevin D. Cashman, Cyrus Cooper, Kay Tee Khaw, Susan Lanham-New, Helen Macdonald, Ann Prentice, Martin Shearer, Alison Stephen
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- Journal:
- British Journal of Nutrition / Volume 99 / Issue 1 / January 2008
- Published online by Cambridge University Press:
- 17 December 2007, pp. 198-205
- Print publication:
- January 2008
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The UK Food Standards Agency convened an international group of expert scientists to review the Agency-funded projects on diet and bone health in the context of developments in the field as a whole. The potential benefits of fruit and vegetables, vitamin K, early-life nutrition and vitamin D on bone health were presented and reviewed. The workshop reached two conclusions which have public health implications. First, that promoting a diet rich in fruit and vegetable intakes might be beneficial to bone health and would be very unlikely to produce adverse consequences on bone health. The mechanism(s) for any effect of fruit and vegetables remains unknown, but the results from these projects did not support the postulated acid–base balance hypothesis. Secondly, increased dietary consumption of vitamin K may contribute to bone health, possibly through its ability to increase the γ-carboxylation status of bone proteins such as osteocalcin. A supplementation trial comparing vitamin K supplementation with Ca and vitamin D showed an additional effect of vitamin K against baseline levels of bone mineral density, but the benefit was only seen at one bone site. The major research gap identified was the need to investigate vitamin D status to define deficiency, insufficiency and depletion across age and ethnic groups in relation to bone health.