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The CODATwins Project: The Current Status and Recent Findings of COllaborative Project of Development of Anthropometrical Measures in Twins
- K. Silventoinen, A. Jelenkovic, Y. Yokoyama, R. Sund, M. Sugawara, M. Tanaka, S. Matsumoto, L. H. Bogl, D. L. Freitas, J. A. Maia, J. v. B. Hjelmborg, S. Aaltonen, M. Piirtola, A. Latvala, L. Calais-Ferreira, V. C. Oliveira, P. H. Ferreira, F. Ji, F. Ning, Z. Pang, J. R. Ordoñana, J. F. Sánchez-Romera, L. Colodro-Conde, S. A. Burt, K. L. Klump, N. G. Martin, S. E. Medland, G. W. Montgomery, C. Kandler, T. A. McAdams, T. C. Eley, A. M. Gregory, K. J. Saudino, L. Dubois, M. Boivin, M. Brendgen, G. Dionne, F. Vitaro, A. D. Tarnoki, D. L. Tarnoki, C. M. A. Haworth, R. Plomin, S. Y. Öncel, F. Aliev, E. Medda, L. Nisticò, V. Toccaceli, J. M. Craig, R. Saffery, S. H. Siribaddana, M. Hotopf, A. Sumathipala, F. Rijsdijk, H.-U. Jeong, T. Spector, M. Mangino, G. Lachance, M. Gatz, D. A. Butler, W. Gao, C. Yu, L. Li, G. Bayasgalan, D. Narandalai, K. P. Harden, E. M. Tucker-Drob, K. Christensen, A. Skytthe, K. O. Kyvik, C. A. Derom, R. F. Vlietinck, R. J. F. Loos, W. Cozen, A. E. Hwang, T. M. Mack, M. He, X. Ding, J. L. Silberg, H. H. Maes, T. L. Cutler, J. L. Hopper, P. K. E. Magnusson, N. L. Pedersen, A. K. Dahl Aslan, L. A. Baker, C. Tuvblad, M. Bjerregaard-Andersen, H. Beck-Nielsen, M. Sodemann, V. Ullemar, C. Almqvist, Q. Tan, D. Zhang, G. E. Swan, R. Krasnow, K. L. Jang, A. Knafo-Noam, D. Mankuta, L. Abramson, P. Lichtenstein, R. F. Krueger, M. McGue, S. Pahlen, P. Tynelius, F. Rasmussen, G. E. Duncan, D. Buchwald, R. P. Corley, B. M. Huibregtse, T. L. Nelson, K. E. Whitfield, C. E. Franz, W. S. Kremen, M. J. Lyons, S. Ooki, I. Brandt, T. S. Nilsen, J. R. Harris, J. Sung, H. A. Park, J. Lee, S. J. Lee, G. Willemsen, M. Bartels, C. E. M. van Beijsterveldt, C. H. Llewellyn, A. Fisher, E. Rebato, A. Busjahn, R. Tomizawa, F. Inui, M. Watanabe, C. Honda, N. Sakai, Y.-M. Hur, T. I. A. Sørensen, D. I. Boomsma, J. Kaprio
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- Journal:
- Twin Research and Human Genetics / Volume 22 / Issue 6 / December 2019
- Published online by Cambridge University Press:
- 31 July 2019, pp. 800-808
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The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
Paleoclimatic and paleogeographic implications of a lower Tertiary laterite (latosol) on the Iceland—Faeroe Ridge, North Atlantic region
- T. H. Nilsen, D. R. Kerr
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- Journal:
- Geological Magazine / Volume 115 / Issue 3 / May 1978
- Published online by Cambridge University Press:
- 01 May 2009, pp. 153-182
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A lower Tertiary lateritic paleosol resting on a plateau basalt was penetrated by drilling at DSDP Site 336 on the NE flank of the Iceland—Faeroe Ridge. The sea floor at the site is about 800 m below sea level and about 400 m below the generally smooth, flat and largely sediment-free top of the ridge. The paleosol is approximately 30 m thick and can be divided into four subunits, in ascending order, basaltic rubble, red clay with altered basaltic clasts, interlayered red and pale-orange clay, and red clay. The paleosol is overlain by about 300 m of marine mudstone of medial Eocene to medial late Oligocene age that was deposited in progressively deeper water through time. About 170 m of Pliocene and Pleistocene glacio-marine sediments unconformably overlie the Paleogene deposits.
In the lowest subunit of the paleosol, feldspar, pyroxene, magnetite and chlorite decrease in abundance abruptly upward and are replaced by montmorillonite and small amounts of hematite and goethite. At the contact between the second and third subunits of the paleosol, kaolinite becomes an important constituent and increases greatly in abundance upward. In the uppermost red clay subunit, kaolinite has completely replaced montmorillonite and the amount of hematite and goethite increases markedly. Within the paleosol subunits, the relative amounts of silicon, ferrous iron, magnesium, calcium, sodium, and potassium decrease upward, whereas the amounts of aluminum, ferric iron, and titanium increase upward. The red and pale-orange clay subunit contains layers characterized by veinlet-like structures alternating with more massive layers. The veinlet network is thought to have developed by segregation of ferric iron and alumina as a result of chemical weathering of basalt and possibly thin overlying airfall tuffs.
The paleosol indicates a humid, warm climate and demonstrates that the Iceland-Faeroe Ridge was above sea level during the early Tertiary. The ridge formed the main part of the Thulean land bridge that permitted free migration of land mammals between North America-Greenland and Europe prior to late Eocene time. It developed during the early Tertiary break-up and rifting apart of North America-Greenland and Europe. Formerly situated over an active mantle plume or hot spot, the ridge subsequently subsided in late Eocene and Oligocene time, eventually permittingfree interchange of marine waters between the Norwegian-Greenland Sea and the North Atlantic Ocean. Basalts of the Iceland-Faeroe Ridge are simijar in age and character to other basalts of the North Atlantic early Tertiary igneous province on the Rockall and Voring Plateaus, northern Ireland, Scotland, the Faeroe Islands, East and West Greenland, and Baffin Island. Bauxite, lignite, and laterite associated with some of these basalt sequences, as well as vertebrate, plant, and microfossil remains, suggest a relatively uniform, warm, humid climate in the early Tertiary throughout the North Atlantic area and into the region of the Arctic Ocean.
5 - The Mid-Appalachian Shale Barrens
- Edited by Roger C. Anderson, Illinois State University, James S. Fralish, Southern Illinois University, Carbondale, Jerry M. Baskin, University of Kentucky
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- Book:
- Savannas, Barrens, and Rock Outcrop Plant Communities of North America
- Published online:
- 21 October 2009
- Print publication:
- 28 July 1999, pp 83-98
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Summary
Introduction
Shale barrens have been a source of fascination to naturalists for the past one hundred years. In the late 19th and early 20th century, botanists noticed sites in the Middle Appalachians supporting an unusual herbaceous flora distinct from the surrounding eastern deciduous forest. Steele (1911) formally introduced shale barren communities to botanists with the following passage:
Several of the species considered are inhabitants of a type of land widely distributed through the mountains of middle Virginia which might well be denominated “shale barrens.” … The barrenness is perhaps largely due to the constant washing away of fine particles of soil, but in some cases it seems as if it must be chargeable to chemical composition. … The variety of plant life is very considerable and together with many plants well known on other substrata, these barrens possess a number peculiar unto themselves.
Thus, the first description delineated shale barren communities on the basis of substrate and presence of a unique flora. In addition, Steele (1911) speculated that in at least some cases soil chemistry must be a factor creating barrens. According to Platt (1951), a surface layer of rock fragments and its rapid erosion are important in maintaining shale barrens. Therefore, it is the structural characteristics of the ground surface and root zone that set shale barren communities apart from the surrounding sandstone ridges and limestone valleys.
Nevertheless, soil features alone are not adequate to delineate a shale barren community.