Search

Your search keyword '"Pálsson G"' showing total 75 results
Start Over Author "Pálsson G"
75 results on '"Pálsson G"'

1. Hard x-ray standing-wave photoemission study of the interfaces in a BiFeO$_3$/La$_{0.7}$Sr$_{0.3}$MnO$_3$ superlattice

Author

Martins, H. P., Khan, S. A., Conti, G., Greer, A. A., Saw, A. Y., Palsson, G. K., Huijben, M., Kobayashi, K., Ueda, S., Schneider, C. M., Vishik, I. M., Minár, J., Gray, A. X., Fadley, C. S., and Nemšák, S.

Subjects
Condensed Matter - Materials Science
Abstract

Hybrid multiferroics such as BiFeO$_3$ (BFO) and La$_{0.7}$Sr$_{0.3}$MnO$_3$ (LSMO) heterostructures are highly interesting functional systems due to their complex electronic and magnetic properties. One of the key parameters influencing the emergent properties is the quality of interfaces, where varying interdiffusion lengths can give rise to different chemistry and distinctive electronic states. Here we report high-resolution depth resolved chemical and electronic investigation of BFO/LSMO superlattice using standing-wave hard X-ray photoemission spectroscopy in the first-order Bragg as well as near-total-reflection geometry. Our results show that the interfaces of BFO on top of LSMO are atomically abrupt, while the LSMO on top of BFO interfaces show an interdiffusion length of around 1.2 unit cells. The two interfaces also exhibit different chemical gradients, with the BFO/LSMO interface being Sr-terminated by a spectroscopically distinctive high binding energy component in Sr 2p core-level spectra, which is spatially contained within 1 unit cell from the interface. From the electronic point of view, unique valence band features were observed for bulk-BFO, bulk-LSMO and their interfaces. Our X-ray optical analysis revealed a unique electronic signature at the BFO/LSMO interface, which we attribute to the coupling between those respective layers. Valence band decomposition based on the Bragg-reflection standing-wave measurement also revealed the band alignment between BFO and LSMO layers. Our work demonstrates that standing-wave hard x-ray photoemission is a reliable non-destructive technique for probing depth-resolved electronic structure of buried layers and interfaces with sub-unit-cell resolution. Equivalent investigations can be successfully applied to a broad class of material such as perovskite complex oxides with emergent interfacial phenomena.

Published
2020

2. Hard x-ray standing-wave photoemission insights into the structure of an epitaxial Fe/MgO multilayer magnetic tunnel junction

Author

Conlon, C. S., Conti, G., Nemšák, S., Palsson, G., Moubah, R., Kuo, C. -T., Gehlmann, M., Ciston, J., Rault, J., Rueff, J. -P., Salmassi, F., Stolte, W., Rattanachata, A., Lin, S. -C., Keqi, A., Saw, A., Hjörvarsson, B., and Fadley, C. S.

Subjects
Condensed Matter - Materials Science, Condensed Matter - Mesoscale and Nanoscale Physics
Abstract

The Fe/MgO magnetic tunnel junction is a classic spintronic system, with current importance technologically, and interest for future innovation. The key magnetic properties are linked directly to the structure of hard-to-access buried interfaces, and the Fe and MgO components near the surface are unstable when exposed to air, making a deeper probing, non-destructive, in-situ measurement ideal for this system. We have thus applied hard x-ray photoemission spectroscopy (HXPS) and standing-wave (SW) HXPS in the few keV energy range to probe the structure of an epitaxially-grown MgO/Fe superlattice. The superlattice consists of 9 repeats of MgO grown on Fe by magnetron sputtering on an MgO (001) substrate, with a protective Al2O3 capping layer. We determine through SW-HXPS that 8 of the 9 repeats are similar and ordered, with a period of 33 $\pm$ 4 angstrom, with minor presence of FeO at the interfaces and a significantly distorted top bilayer with ca. 3 times the oxidation of the lower layers at the top MgO/Fe interface. There is evidence of asymmetrical oxidation on the top and bottom of the Fe layers. We find agreement with dark-field scanning transmission electron microscope (STEM) and x-ray reflectivity measurements. Through the STEM measurements we confirm an overall epitaxial stack with dislocations and warping at the interfaces of ca. 5 angstrom. We also note a distinct difference in the top bilayer, especially MgO, with possible Fe inclusions. We thus demonstrate that SW-HXPS can be used to probe deep buried interfaces of novel magnetic devices with few angstrom precision., Comment: 37 pages, 13 figures

Published
2019
Full Text
View/download PDF

3. Depth profiling charge accumulation from a ferroelectric into a doped Mott insulator

Author

Marinova, M., Rault, J. E., Gloter, A., Nemsak, S., Palsson, G. K., Rueff, J. -P., Fadley, C. S., Carretero, C., Yamada, H., March, K., Garcia, V., Fusil, S., Barthelemy, A., Stephan, O., Colliex, C., and Bibes, M.

Subjects
Condensed Matter - Materials Science
Abstract

The electric field control of functional properties is a crucial goal in oxide-based electronics. Non-volatile switching between different resistivity or magnetic states in an oxide channel can be achieved through charge accumulation or depletion from an adjacent ferroelectric. However, the way in which charge distributes near the interface between the ferroelectric and the oxide remains poorly known, which limits our understanding of such switching effects. Here we use a first-of-a-kind combination of scanning transmission electron microscopy with electron energy loss spectroscopy, near-total-reflection hard X-ray photoemission spectroscopy, and ab-initio theory to address this issue. We achieve a direct, quantitative, atomic-scale characterization of the polarization-induced charge density changes at the interface between the ferroelectric BiFeO3 and the doped Mott insulator Ca1-xCexMnO3, thus providing insight on how interface-engineering can enhance these switching effects., Comment: Work supported by ERC Consolidator grant MINT (Contract No. 615759)

Published
2017
Full Text
View/download PDF

4. Depth-Resolved Composition and Electronic Structure of Buried Layers and Interfaces in a LaNiO$_3$/SrTiO$_3$ Superlattice from Soft- and Hard- X-ray Standing-Wave Angle-Resolved Photoemission

Author

Eiteneer, D., Pálsson, G. K., Nemšák, S., Gray, A. X., Kaiser, A. M., Son, J., LeBeau, J., Conti, G., Greer, A. A., Keqi, A., Rattanachata, A., Saw, A. Y., Bostwick, A., Rotenberg, E., Gullikson, E. M., Ueda, S., Kobayashi, K., Janotti, A., Van de Walle, C. G., Blanca-Romero, A., Pentcheva, R., Schneider, C. M., Stemmer, S., and Fadley, C. S.

Subjects
Condensed Matter - Strongly Correlated Electrons
Abstract

LaNiO$_3$ (LNO) is an intriguing member of the rare-earth nickelates in exhibiting a metal-insulator transition for a critical film thickness of about 4 unit cells [Son et al., Appl. Phys. Lett. 96, 062114 (2010)]; however, such thin films also show a transition to a metallic state in superlattices with SrTiO$_3$ (STO) [Son et al., Appl. Phys. Lett. 97, 202109 (2010)]. In order to better understand this transition, we have studied a strained LNO/STO superlattice with 10 repeats of [4 unit-cell LNO/3 unit-cell STO] grown on an (LaAlO$_3$)$_{0.3}$(Sr$_2$AlTaO$_6$)$_{0.7}$ substrate using soft x-ray standing-wave-excited angle-resolved photoemission (SWARPES), together with soft- and hard- x-ray photoemission measurements of core levels and densities-of-states valence spectra. The experimental results are compared with state-of-the-art density functional theory (DFT) calculations of band structures and densities of states. Using core-level rocking curves and x-ray optical modeling to assess the position of the standing wave, SWARPES measurements are carried out for various incidence angles and used to determine interface-specific changes in momentum-resolved electronic structure. We further show that the momentum-resolved behavior of the Ni 3d eg and t2g states near the Fermi level, as well as those at the bottom of the valence bands, is very similar to recently published SWARPES results for a related La$_{0.7}$Sr$_{0.3}$MnO$_3$/SrTiO$_3$ superlattice that was studied using the same technique (Gray et al., Europhysics Letters 104, 17004 (2013)), which further validates this experimental approach and our conclusions. Our conclusions are also supported in several ways by comparison to DFT calculations for the parent materials and the superlattice, including layer-resolved density-of-states results.

Published
2015
Full Text
View/download PDF

5. Observation by resonant angle-resolved photoemission of a critical thickness for 2-dimensional electron gas formation in SrTiO$_3$ embedded in GdTiO$_3$

Author

Nemšák, S., Conti, G., Pálsson, G. K., Conlon, C., Cho, S., Rault, J., Avila, J., Asensio, M. -C., Jackson, C., Moetakef, P., Janotti, A., Bjaalie, L., Himmetoglu, B., Van de Walle, C. G., Balents, L., Schneider, C. M., Stemmer, S., and Fadley`, C. S.

Subjects
Condensed Matter - Materials Science, Condensed Matter - Strongly Correlated Electrons
Abstract

For certain conditions of layer thickness, the interface between GdTiO$_3$ (GTO) and SrTiO$_3$ (STO) in multilayer samples has been found to form a two-dimensional electron gas (2DEG) with very interesting properties including high mobilities and ferromagnetism. We have here studied two trilayer samples of the form [2 nm GTO/1.0 or 1.5 unit cells STO/10 nm GTO] as grown on (001) (LaAlO$_3$)$_{0.3}$(Sr$_2$AlTaO$_6$)$_{0.7}$ (LSAT), with the STO layer thicknesses being at what has been suggested is the critical thickness for 2DEG formation. We have studied these with Ti-resonant angle-resolved (ARPES) and angle-integrated photoemission and find that the spectral feature in the spectra associated with the 2DEG is present in the 1.5 unit cell sample, but not in the 1.0 unit cell sample. We also observe through core-level spectra additional states in Ti and Sr, with the strength of a low-binding-energy state for Sr being associated with the appearance of the 2DEG, and we suggest it to have an origin in final-state core-hole screening., Comment: 12 pages, 4 figures

Published
2015
Full Text
View/download PDF

6. Energetic, spatial and momentum character of a buried interface: the two-dimensional electron gas between two metal oxides

Author

Nemšák, S., Conti, G., Gray, A. X., Pálsson, G. K., Conlon, C., Eiteneer, D., Keqi, A., Rattanachata, A., Saw, A. Y., Bostwick, A., Moreschini, L., Strocov, V., Kobayashi, M., Stolte, W., Ueda, S., Kobayashi, K., Gloskovskii, A., Drube, W., Jackson, C., Moetakef, P., Janotti, A., Bjaalie, L., Himmetoglu, B., Van de Walle, C. G., Borek, S., Minár, J., Braun, J., Ebert, H., Plucinski, L., Kortright, J. B., de Groot, F. M. F., Schneider, C. M., Balents, L., Stemmer, S., and Fadley, C. S.

Subjects
Condensed Matter - Materials Science, Condensed Matter - Other Condensed Matter, Condensed Matter - Strongly Correlated Electrons
Abstract

The interfaces between two condensed phases often exhibit emergent physical properties that can lead to new physics and novel device applications, and are the subject of intense study in many disciplines. We here apply novel experimental and theoretical techniques to the characterization of one such interesting interface system: the two-dimensional electron gas (2DEG) formed in multilayers consisting of SrTiO$_3$ (STO) and GdTiO$_3$ (GTO). This system has been the subject of multiple studies recently and shown to exhibit very high carrier charge densities and ferromagnetic effects, among other intriguing properties. We have studied a 2DEG-forming multilayer of the form [6 unit cells STO/3 unit cells of GTO]$_{20}$ using a unique array of photoemission techniques including soft and hard x-ray excitation, soft x-ray angle-resolved photoemission, core-level spectroscopy, resonant excitation, and standing-wave effects, as well as theoretical calculations of the electronic structure at several levels and of the actual photoemission process. Standing-wave measurements below and above a strong resonance have been introduced as a powerful method for studying the 2DEG depth distribution. We have thus characterized the spatial and momentum properties of this 2DEG with unprecedented detail, determining via depth-distribution measurements that it is spread throughout the 6 u.c. layer of STO, and measuring the momentum dispersion of its states. The experimental results are supported in several ways by theory, leading to a much more complete picture of the nature of this 2DEG, and suggesting that oxygen vacancies are not the origin of it. Similar multi-technique photoemission studies of such states at buried interfaces, combined with comparable theory, will be a very fruitful future approach for exploring and modifying the fascinating world of buried-interface physics and chemistry., Comment: 34 pages, 10 figures

Published
2015
Full Text
View/download PDF

7. Satellite Band Structure in Silicon Caused by Electron-Plasmon Coupling

Author

Lischner, Johannes, Palsson, G. K., Vigil-Fowler, Derek, Nemsak, S., Avila, J., Asensio, M. C., Fadley, C. S., and Louie, S. G.

Subjects
Condensed Matter - Materials Science
Abstract

We report the first angle-resolved photoemission measurement of the wave-vector dependent plasmon satellite structure of a three-dimensional solid, crystalline silicon. In sharp contrast to nanomaterials, which typically exhibit strongly wave-vector dependent, low-energy plasmons, the large plasmon energy of silicon facilitates the search for a plasmaron state consisting of resonantly bound holes and plasmons and its distinction from a weakly interacting plasmon-hole pair. Employing a first-principles theory, which is based on a cumulant expansion of the one-electron Green's function and contains significant electron correlation effects, we obtain good agreement with the measured photoemission spectrum for the wave-vector dependent dispersion of the satellite feature, but without observing the existence of plasmarons in the calculations., Comment: 7 pages, 5 figures, accepted for publication in PRB

Published
2015
Full Text
View/download PDF

8. Mg/Ti multilayers: structural, optical and hydrogen absorption properties

Author

Baldi, A., Palsson, G. K., Gonzalez-Silveira, M., Schreuders, H., Slaman, M., Rector, J. H., Krishnan, G., Kooi, B. J., Walker, G. S., Fay, M. W., Hjorvarsson, B., Wijngaarden, R. J., Dam, B., and Griessen, R.

Subjects
Condensed Matter - Materials Science
Abstract

Mg-Ti alloys have uncommon optical and hydrogen absorbing properties, originating from a "spinodal-like" microstructure with a small degree of chemical short-range order in the atoms distribution. In the present study we artificially engineer short-range order by depositing Pd-capped Mg/Ti multilayers with different periodicities and characterize them both structurally and optically. Notwithstanding the large lattice parameter mismatch between Mg and Ti, the as-deposited metallic multilayers show good structural coherence. Upon exposure to H2 gas a two-step hydrogenation process occurs, with the Ti layers forming the hydride before Mg. From in-situ measurements of the bilayer thickness L at different hydrogen pressures, we observe large out-of-plane expansions of the Mg and Ti layers upon hydrogenation, indicating strong plastic deformations in the films and a consequent shortening of the coherence length. Upon unloading at room temperature in air, hydrogen atoms remain trapped in the Ti layers due to kinetic constraints. Such loading/unloading sequence can be explained in terms of the different thermodynamic properties of hydrogen in Mg and Ti, as shown by diffusion calculations on a model multilayered systems. Absorption isotherms measured by hydrogenography can be interpreted as a result of the elastic clamping arising from strongly bonded Mg/Pd and broken Mg/Ti interfaces.

Published
2009
Full Text
View/download PDF

9. Towards realistic electronic structure calculations of strongly correlated electron systems

Author

Oudovenko, V. S., Palsson, G., Haule, K., Savrasov, S. Y., and Kotliar, G.

Subjects
Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Materials Science
Abstract

We review some aspects of the realistic implementation of the dynamical mean-field method. We extend the techniques introduced in Ref.[A. Georges, G. Kotliar, W. Krauth, and M.J. Rozenberg, Rev. Mod. Phys. 68, 13 (1996)] to include the calculations of transport coefficients. The approach is illustrated on La_{1-x}Sr_xTiO_3 material undergoing a density driven Mott transition., Comment: 29 pages, 25 PS figures, in RevTex format

Published
2004

10. Calculations of Optical Properties in Strongly Correlated Materials

Author

Oudovenko, V. S., Palsson, G., Haule, K., Savrasov, S. Y., and Kotliar, G.

Subjects
Condensed Matter - Strongly Correlated Electrons
Abstract

We present a new method to calculate optical properties of strongly correlated systems. It is based on dynamical mean field theory and it uses as an input realistic electronic structure obtained by local density functional calculations. Numerically tractable equations for optical conductivity, which show a correct non-interacting limit, are derived. Illustration of the method is given by computing optical properties of the doped Mott insulator La_{1-x}Sr_xTiO_3., Comment: 7 pages, 3 EPS figures, in Phys. Rev format

Published
2002

16. Associations of autozygosity with a broad range of human phenotypes

Author

Clark, D.W. (David W), Okada, Y. (Yukinori), Moore, K.H.S. (Kristjan H S), Mason, D. (Dan), Pirastu, N. (Nicola), Gandin, I. (Ilaria), Mattsson, H. (Hannele), Barnes, C.L.K. (Catriona L K), Lin, K. (Kuang), Zhao, J.H. (Jing Hua), Deelen, P. (Patrick), Rohde, R. (Rebecca), Schurmann, C. (Claudia), Guo, X. (Xiuqing), Giulianini, F. (Franco), Zhang, W. (Weihua), Medina-Gomez, M.C. (Carolina), Karlsson, R. (Robert), Bao, Y. (Yanchun), Bartz, T.M. (Traci M), Baumbach, C. (Clemens), Biino, G. (Ginevra), Bixley, M.J. (Matthew J), Brumat, M. (Marco), Chai, J.-F. (Jin-Fang), Corre, T. (Tanguy), Cousminer, D.L. (Diana), Dekker, A.M. (Annelot M), Eccles, D.A. (David A), Eijk, K.R. (Kristel) van, Fuchsberger, C. (Christian), Gao, H. (He), Germain, M. (Marine), Gordon, S.D. (Scott D.), de Haan, H.G. (Hugoline G), Harris, S.E. (Sarah), Hofer, E. (Edith), Huerta-Chagoya, A. (Alicia), Igartua, C. (Catherine), Jansen, I. (Iris), Jia, Y. (Yucheng), Kacprowski, T. (Tim), Karlsson, T. (Torgny), Kleber, M.E. (Marcus), Li, S.A. (Shengchao Alfred), Li-Gao, R. (Ruifang), Mahajan, A. (Anubha), Matsuda, K. (Koichi), Meidtner, K. (Karina), Meng, W. (Weihua), Montasser, M.E. (May E.), Most, P.J. (Peter) van der, Munz, M. (Matthias), Nutile, T. (Teresa), Palviainen, T. (Teemu), Prasad, G. (Gauri), Prasad, R.B. (Rashmi B), Priyanka, T.D.S. (Tallapragada Divya Sri), Rizzi, F. (Federica), Salvi, E. (Erika), Sapkota, B.R. (Bishwa R), Shriner, D. (Daniel), Skotte, L. (Line), Smart, M.C. (Melissa C), Smith, A.V. (Albert), Spek, A. (Ashley) van der, Spracklen, C.N. (Cassandra N), Strawbridge, R.J. (Rona), Tajuddin, S.M. (Salman M), Trompet, S. (Stella), Turman, C. (Constance), Verweij, N. (Niek), Viberti, C. (Clara), Wang, L. (Lihua), Warren, H. (Helen), Wootton, R.E. (Robyn E), Yanek, L.R. (Lisa), Yao, J. (Jie), Yousri, N.A. (Noha A), Zhao, W. (Wei), Adeyemo, A.A. (Adebowale A), Afaq, S. (Saima), Aguilar-Salinas, C.A. (Carlos Alberto), Akiyama, M. (Masato), Albert, M.L. (Matthew L), Allison, M.A. (Matthew A), Alver, M. (Maris), Aung, T. (Tin), Azizi, J. (Joshan), Bentley, A.R. (Amy), Boeing, H. (Heiner), Boerwinkle, E.A. (Eric), Borja, J.B. (Judith B), Borst, G.J. (Gert) de, Bottinger, E.P. (Erwin), Broer, L. (Linda), Campbell, H. (Harry), Chanock, S.J. (Stephen), Chee, M.-L. (Miao-Li), Chen, G. (Guanjie), Chen, Y.-D.I. (Yii-Der I), Chen, Z. (Zhengming), Chiu, Y.-F. (Yen-Feng), Cocca, M. (Massimiliano), Collins, F.S. (Francis), Concas, M.P. (Maria Pina), Corley, J. (Janie), Cugliari, G. (Giovanni), Dam, R.M. (Rob) van, Damulina, A. (Anna), Daneshpour, M.S. (Maryam S), Day, F.R. (Felix), Delgado, G., Dhana, K. (Klodian), Doney, A.S.F. (Alex), Dörr, M. (Marcus), Doumatey, A. (Ayo), Dzimiri, N. (Nduna), Ebenesersdóttir, S.S. (S Sunna), Elliott, J. (Joshua), Elliott, P. (Paul), Ewert, R. (Ralf), Felix, J.F. (Janine), Fischer, K. (Krista), Freedman, B.I. (Barry), Girotto, S., Goel, A. (Anuj), Gögele, M. (Martin), Goodarzi, M. (Mark), Graff, M.J. (Maud J.L.), Granot-Hershkovitz, E. (Einat), Grodstein, F. (Francine), Guarrera, S. (Simonetta), Gudbjartsson, D.F. (Daniel), Guity, K. (Kamran), Gunnarsson, B. (Bjarni), Guo, Y. (Yu), Hagenaars, S.P. (Saskia P), Haiman, C.A. (Christopher), Halevy, A. (Avner), Harris, T.B. (Tamara B), Hedayati, M. (Mehdi), Heel, D.A. (David) van, Hirata, M. (Makoto), Höfer, I. (Imo), Hsiung, C.A. (Chao Agnes), Huang, J. (Jinyan), Hung, Y.-J. (Yi-Jen), Ikram, M.A. (Arfan), Jagadeesan, A. (Anuradha), Jousilahti, P. (Pekka), Kamatani, Y. (Yoichiro), Kanai, M. (Masahiro), Kerrison, N.D. (Nicola D), Kessler, T. (Thorsten), Khaw, K.-T. (Kay-Tee), Khor, C.C., Kleijn, D.P.V. (Dominique) de, Koh, W.-P. (Woon-Puay), Kolcic, I. (Ivana), Kraft, P. (Peter), Krämer, B.K. (Bernhard), Kutalik, Z. (Zoltán), Kuusisto, J. (Johanna), Langenberg, C. (Claudia), Launer, L.J. (Lenore), Lawlor, D.A. (Debbie), Lee, I.-T. (I-Te), Lee, W.-J. (Wen-Jane), Lerch, M. (M.), Li, L. (Liming), Liu, J. (Jianjun), Loh, M. (Marie), London, S.J. (Stephanie J), Loomis, S.J. (Stephanie J.), Lu, Y. (Yingchang), Luan, J. (Jian’an), Mägi, R. (Reedik), Manichaikul, A.W. (Ani W), Manunta, P. (Paolo), Masson, G. (Gisli), Matoba, N. (Nana), Mei, X.W. (Xue W), Meisinger, C. (Christa), Meitinger, T. (Thomas), Mezzavilla, M. (Massimo), Milani, L. (Lili), Millwood, I.Y. (Iona), Momozawa, Y. (Yukihide), Moore, A. (Amy), Morange, P.-E. (P.), Moreno-Macías, H. (Hortensia), Mori, T.A. (Trevor A), Morrison, A.C. (Alanna), Muka, T. (Taulant), Murakami, Y. (Yoshinori), Murray, A.D. (Alison D), Mutsert, R. (Reneé) de, Mychaleckyj, J.C. (Josyf), Nalls, M.A. (Michael), Nauck, M. (Matthias), Neville, M.J. (Matthew), Nolte, I.M. (Ilja), Ong, K.K. (Ken K), Orozco, L. (Lorena), Padmanabhan, S. (Sandosh), Pálsson, G. (Gunnar), Palmer, C.N.A. (Colin), Penninx, B.W.J.H., Pattie, A. (Alison), Polasek, O. (Ozren), Poulter, N.R. (Neil), Pramstaller, P.P. (Peter P), Quintana-Murci, L. (Lluis), Räikkönen, K. (Katri), Ralhan, S. (Sarju), Rao, D.C. (Dabeeru C), Rheenen, W. (Wouter) van, Rich, S.S. (Stephen), Ridker, P.M. (Paul M), Rietveld, C.A. (Cornelius A), Robino, A. (Antonietta), Rooij, F.J.A. (Frank) van, Ruggiero, D., Saba, Y. (Yasaman), Sabanayagam, C. (Charumathi), Sabater-Lleal, M. (Maria), Sala, C. (Cinzia), Salomaa, V. (Veikko), Sandow, K. (Kevin), Schmidt, H. (Helena), Scott, L.J. (Laura J), Scott, W.R. (William R), Sedaghati-Khayat, B. (Bahareh), Sennblad, B. (Bengt), Setten, J. (Jessica) van, Sever, P.J. (Peter J), Sheu, W.H.-H. (Wayne H-H), Shi, Y. (Yuan), Shrestha, S. (Smeeta), Shukla, S.R. (Sharvari Rahul), Sigurdsson, J.K. (Jon K), Sikka, T.T. (Timo Tonis), Singh, J.R. (Jai Rup), Smith, B.H. (Blair), Stancáková, A. (Alena), Stanton, A. (Alice), Starr, J.M. (John), Stefansdottir, L. (Lilja), Straker, L. (Leon), Sulem, P. (Patrick), Sveinbjornsson, G. (Gardar), Swertz, M.A. (Morris A), Taylor, A.M. (Adele M), Taylor, K.D. (Kent), Terzikhan, N. (Natalie), Tham, Y.-C. (Yih-Chung), Thorleifsson, G. (Gudmar), Thorsteinsdottir, U. (Unnur), Tillander, A. (Annika), Tracy, R.P. (Russell), Tusié-Luna, T. (Teresa), Tzoulaki, I., Vaccargiu, S. (Simona), Vangipurapu, J. (Jagadish), Veldink, J.H. (Jan), Vitart, V. (Veronique), Völker, U. (Uwe), Vuoksimaa, E. (Eero), Wakil, S.M. (Salma M), Waldenberger, M. (Melanie), Wander, G.S. (Gurpreet S), Wang, Y.X. (Ya Xing), Wareham, N.J. (Nick), Wild, S.H. (Sarah), Yajnik, C.S. (Chittaranjan S), Yuan, J.-M. (Jian-Min), Zeng, L. (Lingyao), Zhang, L. (Liang), Zhou, J. (Jie), Amin, N. (Najaf), Asselbergs, F.W. (Folkert), Bakker, S.J.L. (Stephan), Becker, D.M. (Diane), Lehne, B. (Benjamin), Bennett, D.A. (David), Berg, L.H. (Leonard) van den, Berndt, S.I. (Sonja), Bharadwaj, D. (Dwaipayan), Bielak, L.F. (Lawrence F.), Bochud, M. (Murielle), Boehnke, M. (Michael), Bouchard, C. (Claude), Bradfield, J.P. (Jonathan), Brody, J.A. (Jennifer A), Campbell, A. (Archie), Carmi, S. (Shai), Caulfield, M. (Mark), Cesarini, D. (David), Chambers, J.C. (John C), Chandak, G.R. (Giriraj), Cheng, C.-Y. (Ching-Yu), Ciullo, M. (Marina), Warrington, N.M. (Nicole), Cusi, D. (Daniele), Smith, G.D. (George Davey), Deary, I.J. (Ian J), Dorajoo, R. (Rajkumar), Duijn, C.M. (Cornelia) van, Ellinghaus, D. (David), Erdmann, J. (Jeanette), Hagen, K. (Knut), Evangelou, E. (Evangelos), Evans, M.K. (Michele), Faul, J.D. (Jessica D), Feenstra, B. (Bjarke), Feitosa, M.F. (Mary Furlan), Foisy, S. (Sylvain), Franke, A. (Andre), Friedlander, Y. (Yechiel), Gasparini, P. (Paolo), Gieger, C. (Christian), Gonzalez, C. (Clicerio), Goyette, P. (Philippe), Grant, S.F.A. (Struan), Griffiths, L.R. (Lyn R), Groop, L. (Leif), Gudnason, V. (Vilmundur), Gyllensten, U. (Ulf), Hakonarson, H. (Hakon), Hamsten, A. (Anders), Harst, P. (Pim) van der, Heng, C.K. (Chew-Kiat), Hicks, A.A. (Andrew A), Hochner, H., Huikuri, H.V. (Heikki), Hunt, S.C. (Steven), Jaddoe, V.W.V. (Vincent), De Jager, P., Johannesson, M. (Magnus), Johansson, A. (Åsa), Jonas, J.B. (Jost B), Jukema, J.W. (Jan Wouter), Junttila, M.J. (Juhani), Kaprio, J. (Jaakko), Kardia, S.L.R. (Sharon), Karpe, F. (Fredrik), Kumari, M. (Meena), Laakso, M. (Markku), van der Laan, S.W. (Sander W), Lahti, J. (Jari), Laudes, M. (Matthias), Lea, R.A. (Rodney A), Lieb, W. (Wolfgang), Lumley, T. (Thomas), Martin, N.G. (Nicholas), Ye, S. (Shu), Matullo, G., McCarthy, M.I. (Mark), Medland, S.E. (Sarah), Merriman, A., Metspalu, A. (Andres), Meyer, B.F. (Brian F), Mohlke, K.L. (Karen L), Montgomery, G.W. (Grant), Mook-Kanamori, D. (Dennis), Munroe, P. (Patricia), North, K.E. (Kari), Nyholt, D.R. (Dale), O’connell, J.R. (Jeffery R), Ober, C. (Carole), Oldehinkel, A.J. (Albertine), Palmas, W. (Walter), Pasterkamp, G.G. (Gerard G), Patin, E. (Etienne), Pennell, C.E. (Craig), Perusse, L. (Louis), Peyser, P.A. (Patricia A.), Pirastu, M. (Mario), Polderman, T.J.C. (Tinca), Porteous, D.J. (David J.), Posthuma, D. (Danielle), Psaty, B.M. (Bruce M), Rioux, J.D. (John), Rivadeneira, F. (Fernando), Rotimi, C. (Charles), Rotter, J.I. (Jerome I.), Rudan, I. (Igor), Ruijter, H.M. (Hester ) den, Sanghera, D.K. (Dharambir K), Sattar, N. (Naveed), Schmidt, R. (Reinhold), Schulze, M.B. (Matthias), Schunkert, H. (Heribert), Scott, R.A. (Robert), Shuldiner, A.R. (Alan R), Sim, X. (Xueling), Small, N. (Neil), Smith, J.A. (Jennifer A), Sotoodehnia, N. (Nona), Tai, E.-S. (E-Shyong), Teumer, A. (Alexander), Timpson, N.J. (Nicholas), Toniolo, D. (Daniela), Tregouet, D.-A. (David-Alexandre), Tuomi, T. (Tiinamaija), Vollenweider, P. (Peter), Wang, C.A. (Carol A), Weir, D.R. (David R), Whitfield, J. (John), Wijmenga, C. (Cisca), Wong, T.-Y. (Tien-Yin), Wright, J. (John), Yang, J. (Jingyun), Yu, L. (Lei), Zemel, B.S. (Babette S.), Zonderman, A.B. (Alan B), Perola, M. (Markus), Magnusson, P.K. (Patrik), Uitterlinden, A.G. (André), Kooner, J.S. (Jaspal S.), Chasman, D.I. (Daniel), Loos, R.J.F. (Ruth), Franceschini, N. (Nora), Franke, L. (Lude), Haley, C. (Chris), Hayward, C. (Caroline), Walters, R.G. (Robin G), Perry, J.R.B. (John R. B.), Esko, T. (Tõnu), Helgason, A. (Agnar), Zwart, J-A. (John-Anker), Joshi, P.K. (Peter), Kubo, M. (Michiaki), Wilson, J.F. (James), Clark, D.W. (David W), Okada, Y. (Yukinori), Moore, K.H.S. (Kristjan H S), Mason, D. (Dan), Pirastu, N. (Nicola), Gandin, I. (Ilaria), Mattsson, H. (Hannele), Barnes, C.L.K. (Catriona L K), Lin, K. (Kuang), Zhao, J.H. (Jing Hua), Deelen, P. (Patrick), Rohde, R. (Rebecca), Schurmann, C. (Claudia), Guo, X. (Xiuqing), Giulianini, F. (Franco), Zhang, W. (Weihua), Medina-Gomez, M.C. (Carolina), Karlsson, R. (Robert), Bao, Y. (Yanchun), Bartz, T.M. (Traci M), Baumbach, C. (Clemens), Biino, G. (Ginevra), Bixley, M.J. (Matthew J), Brumat, M. (Marco), Chai, J.-F. (Jin-Fang), Corre, T. (Tanguy), Cousminer, D.L. (Diana), Dekker, A.M. (Annelot M), Eccles, D.A. (David A), Eijk, K.R. (Kristel) van, Fuchsberger, C. (Christian), Gao, H. (He), Germain, M. (Marine), Gordon, S.D. (Scott D.), de Haan, H.G. (Hugoline G), Harris, S.E. (Sarah), Hofer, E. (Edith), Huerta-Chagoya, A. (Alicia), Igartua, C. (Catherine), Jansen, I. (Iris), Jia, Y. (Yucheng), Kacprowski, T. (Tim), Karlsson, T. (Torgny), Kleber, M.E. (Marcus), Li, S.A. (Shengchao Alfred), Li-Gao, R. (Ruifang), Mahajan, A. (Anubha), Matsuda, K. (Koichi), Meidtner, K. (Karina), Meng, W. (Weihua), Montasser, M.E. (May E.), Most, P.J. (Peter) van der, Munz, M. (Matthias), Nutile, T. (Teresa), Palviainen, T. (Teemu), Prasad, G. (Gauri), Prasad, R.B. (Rashmi B), Priyanka, T.D.S. (Tallapragada Divya Sri), Rizzi, F. (Federica), Salvi, E. (Erika), Sapkota, B.R. (Bishwa R), Shriner, D. (Daniel), Skotte, L. (Line), Smart, M.C. (Melissa C), Smith, A.V. (Albert), Spek, A. (Ashley) van der, Spracklen, C.N. (Cassandra N), Strawbridge, R.J. (Rona), Tajuddin, S.M. (Salman M), Trompet, S. (Stella), Turman, C. (Constance), Verweij, N. (Niek), Viberti, C. (Clara), Wang, L. (Lihua), Warren, H. (Helen), Wootton, R.E. (Robyn E), Yanek, L.R. (Lisa), Yao, J. (Jie), Yousri, N.A. (Noha A), Zhao, W. (Wei), Adeyemo, A.A. (Adebowale A), Afaq, S. (Saima), Aguilar-Salinas, C.A. (Carlos Alberto), Akiyama, M. (Masato), Albert, M.L. (Matthew L), Allison, M.A. (Matthew A), Alver, M. (Maris), Aung, T. (Tin), Azizi, J. (Joshan), Bentley, A.R. (Amy), Boeing, H. (Heiner), Boerwinkle, E.A. (Eric), Borja, J.B. (Judith B), Borst, G.J. (Gert) de, Bottinger, E.P. (Erwin), Broer, L. (Linda), Campbell, H. (Harry), Chanock, S.J. (Stephen), Chee, M.-L. (Miao-Li), Chen, G. (Guanjie), Chen, Y.-D.I. (Yii-Der I), Chen, Z. (Zhengming), Chiu, Y.-F. (Yen-Feng), Cocca, M. (Massimiliano), Collins, F.S. (Francis), Concas, M.P. (Maria Pina), Corley, J. (Janie), Cugliari, G. (Giovanni), Dam, R.M. (Rob) van, Damulina, A. (Anna), Daneshpour, M.S. (Maryam S), Day, F.R. (Felix), Delgado, G., Dhana, K. (Klodian), Doney, A.S.F. (Alex), Dörr, M. (Marcus), Doumatey, A. (Ayo), Dzimiri, N. (Nduna), Ebenesersdóttir, S.S. (S Sunna), Elliott, J. (Joshua), Elliott, P. (Paul), Ewert, R. (Ralf), Felix, J.F. (Janine), Fischer, K. (Krista), Freedman, B.I. (Barry), Girotto, S., Goel, A. (Anuj), Gögele, M. (Martin), Goodarzi, M. (Mark), Graff, M.J. (Maud J.L.), Granot-Hershkovitz, E. (Einat), Grodstein, F. (Francine), Guarrera, S. (Simonetta), Gudbjartsson, D.F. (Daniel), Guity, K. (Kamran), Gunnarsson, B. (Bjarni), Guo, Y. (Yu), Hagenaars, S.P. (Saskia P), Haiman, C.A. (Christopher), Halevy, A. (Avner), Harris, T.B. (Tamara B), Hedayati, M. (Mehdi), Heel, D.A. (David) van, Hirata, M. (Makoto), Höfer, I. (Imo), Hsiung, C.A. (Chao Agnes), Huang, J. (Jinyan), Hung, Y.-J. (Yi-Jen), Ikram, M.A. (Arfan), Jagadeesan, A. (Anuradha), Jousilahti, P. (Pekka), Kamatani, Y. (Yoichiro), Kanai, M. (Masahiro), Kerrison, N.D. (Nicola D), Kessler, T. (Thorsten), Khaw, K.-T. (Kay-Tee), Khor, C.C., Kleijn, D.P.V. (Dominique) de, Koh, W.-P. (Woon-Puay), Kolcic, I. (Ivana), Kraft, P. (Peter), Krämer, B.K. (Bernhard), Kutalik, Z. (Zoltán), Kuusisto, J. (Johanna), Langenberg, C. (Claudia), Launer, L.J. (Lenore), Lawlor, D.A. (Debbie), Lee, I.-T. (I-Te), Lee, W.-J. (Wen-Jane), Lerch, M. (M.), Li, L. (Liming), Liu, J. (Jianjun), Loh, M. (Marie), London, S.J. (Stephanie J), Loomis, S.J. (Stephanie J.), Lu, Y. (Yingchang), Luan, J. (Jian’an), Mägi, R. (Reedik), Manichaikul, A.W. (Ani W), Manunta, P. (Paolo), Masson, G. (Gisli), Matoba, N. (Nana), Mei, X.W. (Xue W), Meisinger, C. (Christa), Meitinger, T. (Thomas), Mezzavilla, M. (Massimo), Milani, L. (Lili), Millwood, I.Y. (Iona), Momozawa, Y. (Yukihide), Moore, A. (Amy), Morange, P.-E. (P.), Moreno-Macías, H. (Hortensia), Mori, T.A. (Trevor A), Morrison, A.C. (Alanna), Muka, T. (Taulant), Murakami, Y. (Yoshinori), Murray, A.D. (Alison D), Mutsert, R. (Reneé) de, Mychaleckyj, J.C. (Josyf), Nalls, M.A. (Michael), Nauck, M. (Matthias), Neville, M.J. (Matthew), Nolte, I.M. (Ilja), Ong, K.K. (Ken K), Orozco, L. (Lorena), Padmanabhan, S. (Sandosh), Pálsson, G. (Gunnar), Palmer, C.N.A. (Colin), Penninx, B.W.J.H., Pattie, A. (Alison), Polasek, O. (Ozren), Poulter, N.R. (Neil), Pramstaller, P.P. (Peter P), Quintana-Murci, L. (Lluis), Räikkönen, K. (Katri), Ralhan, S. (Sarju), Rao, D.C. (Dabeeru C), Rheenen, W. (Wouter) van, Rich, S.S. (Stephen), Ridker, P.M. (Paul M), Rietveld, C.A. (Cornelius A), Robino, A. (Antonietta), Rooij, F.J.A. (Frank) van, Ruggiero, D., Saba, Y. (Yasaman), Sabanayagam, C. (Charumathi), Sabater-Lleal, M. (Maria), Sala, C. (Cinzia), Salomaa, V. (Veikko), Sandow, K. (Kevin), Schmidt, H. (Helena), Scott, L.J. (Laura J), Scott, W.R. (William R), Sedaghati-Khayat, B. (Bahareh), Sennblad, B. (Bengt), Setten, J. (Jessica) van, Sever, P.J. (Peter J), Sheu, W.H.-H. (Wayne H-H), Shi, Y. (Yuan), Shrestha, S. (Smeeta), Shukla, S.R. (Sharvari Rahul), Sigurdsson, J.K. (Jon K), Sikka, T.T. (Timo Tonis), Singh, J.R. (Jai Rup), Smith, B.H. (Blair), Stancáková, A. (Alena), Stanton, A. (Alice), Starr, J.M. (John), Stefansdottir, L. (Lilja), Straker, L. (Leon), Sulem, P. (Patrick), Sveinbjornsson, G. (Gardar), Swertz, M.A. (Morris A), Taylor, A.M. (Adele M), Taylor, K.D. (Kent), Terzikhan, N. (Natalie), Tham, Y.-C. (Yih-Chung), Thorleifsson, G. (Gudmar), Thorsteinsdottir, U. (Unnur), Tillander, A. (Annika), Tracy, R.P. (Russell), Tusié-Luna, T. (Teresa), Tzoulaki, I., Vaccargiu, S. (Simona), Vangipurapu, J. (Jagadish), Veldink, J.H. (Jan), Vitart, V. (Veronique), Völker, U. (Uwe), Vuoksimaa, E. (Eero), Wakil, S.M. (Salma M), Waldenberger, M. (Melanie), Wander, G.S. (Gurpreet S), Wang, Y.X. (Ya Xing), Wareham, N.J. (Nick), Wild, S.H. (Sarah), Yajnik, C.S. (Chittaranjan S), Yuan, J.-M. (Jian-Min), Zeng, L. (Lingyao), Zhang, L. (Liang), Zhou, J. (Jie), Amin, N. (Najaf), Asselbergs, F.W. (Folkert), Bakker, S.J.L. (Stephan), Becker, D.M. (Diane), Lehne, B. (Benjamin), Bennett, D.A. (David), Berg, L.H. (Leonard) van den, Berndt, S.I. (Sonja), Bharadwaj, D. (Dwaipayan), Bielak, L.F. (Lawrence F.), Bochud, M. (Murielle), Boehnke, M. (Michael), Bouchard, C. (Claude), Bradfield, J.P. (Jonathan), Brody, J.A. (Jennifer A), Campbell, A. (Archie), Carmi, S. (Shai), Caulfield, M. (Mark), Cesarini, D. (David), Chambers, J.C. (John C), Chandak, G.R. (Giriraj), Cheng, C.-Y. (Ching-Yu), Ciullo, M. (Marina), Warrington, N.M. (Nicole), Cusi, D. (Daniele), Smith, G.D. (George Davey), Deary, I.J. (Ian J), Dorajoo, R. (Rajkumar), Duijn, C.M. (Cornelia) van, Ellinghaus, D. (David), Erdmann, J. (Jeanette), Hagen, K. (Knut), Evangelou, E. (Evangelos), Evans, M.K. (Michele), Faul, J.D. (Jessica D), Feenstra, B. (Bjarke), Feitosa, M.F. (Mary Furlan), Foisy, S. (Sylvain), Franke, A. (Andre), Friedlander, Y. (Yechiel), Gasparini, P. (Paolo), Gieger, C. (Christian), Gonzalez, C. (Clicerio), Goyette, P. (Philippe), Grant, S.F.A. (Struan), Griffiths, L.R. (Lyn R), Groop, L. (Leif), Gudnason, V. (Vilmundur), Gyllensten, U. (Ulf), Hakonarson, H. (Hakon), Hamsten, A. (Anders), Harst, P. (Pim) van der, Heng, C.K. (Chew-Kiat), Hicks, A.A. (Andrew A), Hochner, H., Huikuri, H.V. (Heikki), Hunt, S.C. (Steven), Jaddoe, V.W.V. (Vincent), De Jager, P., Johannesson, M. (Magnus), Johansson, A. (Åsa), Jonas, J.B. (Jost B), Jukema, J.W. (Jan Wouter), Junttila, M.J. (Juhani), Kaprio, J. (Jaakko), Kardia, S.L.R. (Sharon), Karpe, F. (Fredrik), Kumari, M. (Meena), Laakso, M. (Markku), van der Laan, S.W. (Sander W), Lahti, J. (Jari), Laudes, M. (Matthias), Lea, R.A. (Rodney A), Lieb, W. (Wolfgang), Lumley, T. (Thomas), Martin, N.G. (Nicholas), Ye, S. (Shu), Matullo, G., McCarthy, M.I. (Mark), Medland, S.E. (Sarah), Merriman, A., Metspalu, A. (Andres), Meyer, B.F. (Brian F), Mohlke, K.L. (Karen L), Montgomery, G.W. (Grant), Mook-Kanamori, D. (Dennis), Munroe, P. (Patricia), North, K.E. (Kari), Nyholt, D.R. (Dale), O’connell, J.R. (Jeffery R), Ober, C. (Carole), Oldehinkel, A.J. (Albertine), Palmas, W. (Walter), Pasterkamp, G.G. (Gerard G), Patin, E. (Etienne), Pennell, C.E. (Craig), Perusse, L. (Louis), Peyser, P.A. (Patricia A.), Pirastu, M. (Mario), Polderman, T.J.C. (Tinca), Porteous, D.J. (David J.), Posthuma, D. (Danielle), Psaty, B.M. (Bruce M), Rioux, J.D. (John), Rivadeneira, F. (Fernando), Rotimi, C. (Charles), Rotter, J.I. (Jerome I.), Rudan, I. (Igor), Ruijter, H.M. (Hester ) den, Sanghera, D.K. (Dharambir K), Sattar, N. (Naveed), Schmidt, R. (Reinhold), Schulze, M.B. (Matthias), Schunkert, H. (Heribert), Scott, R.A. (Robert), Shuldiner, A.R. (Alan R), Sim, X. (Xueling), Small, N. (Neil), Smith, J.A. (Jennifer A), Sotoodehnia, N. (Nona), Tai, E.-S. (E-Shyong), Teumer, A. (Alexander), Timpson, N.J. (Nicholas), Toniolo, D. (Daniela), Tregouet, D.-A. (David-Alexandre), Tuomi, T. (Tiinamaija), Vollenweider, P. (Peter), Wang, C.A. (Carol A), Weir, D.R. (David R), Whitfield, J. (John), Wijmenga, C. (Cisca), Wong, T.-Y. (Tien-Yin), Wright, J. (John), Yang, J. (Jingyun), Yu, L. (Lei), Zemel, B.S. (Babette S.), Zonderman, A.B. (Alan B), Perola, M. (Markus), Magnusson, P.K. (Patrik), Uitterlinden, A.G. (André), Kooner, J.S. (Jaspal S.), Chasman, D.I. (Daniel), Loos, R.J.F. (Ruth), Franceschini, N. (Nora), Franke, L. (Lude), Haley, C. (Chris), Hayward, C. (Caroline), Walters, R.G. (Robin G), Perry, J.R.B. (John R. B.), Esko, T. (Tõnu), Helgason, A. (Agnar), Zwart, J-A. (John-Anker), Joshi, P.K. (Peter), Kubo, M. (Michiaki), and Wilson, J.F. (James)

Abstract

In many species, the offspring of related parents suffer reduced reproductive success, a phenomenon known as inbreeding depression. In humans, the importance of this effect has remained unclear, partly because reproduction between close relatives is both rare and frequently associated with confounding social factors. Here, using genomic inbreeding coefficients (FROH) for >1.4 million individuals, we show that FROH is significantly associated (p < 0.0005) with apparently deleterious changes in 32 out of 100 traits analysed. These changes are associated with runs of homozygosity (ROH), but not with common variant homozygosity, suggesting that genetic variants associated with inbreeding depression are predominantly rare. The effect on fertility is striking: FROH equivalent to the offspring of first cousins is associated with a 55% decrease [95% CI 44–66%] in the odds of having children. Finally, the effects of FROH are confirmed within full-sibling pairs, where the variation in FROH is independent of all environmental confounding.

Published
2019
Full Text
View/download PDF

17. Electronic structure of the dilute magnetic semiconductor G a 1 − x M n x P from hard x-ray photoelectron spectroscopy and angle-resolved photoemission

Author

Keqi, A., Gehlmann, M., Hategan, M., Pálsson, G. K., Conlon, C., Eiteneer, D., Saw, A. Y., Gray, A. X., Kobayashi, K., Ueda, S., Dubon, O. D., Schneider, C. M., Conti, G., Fadley, C. S., Nemsak, Slavomir, Rattanachata, A., Minár, J., Plucinski, L., Rault, J. E., Rueff, J. P., and Scarpulla, M.

Subjects
Condensed Matter::Materials Science, Condensed Matter::Strongly Correlated Electrons, ddc:530
Abstract

We have investigated the electronic structure of the dilute magnetic semiconductor (DMS) Ga0.98Mn0.02P and compared it to that of an undoped GaP reference sample, using hard x-ray photoelectron spectroscopy (HXPS) and hard x-ray angle-resolved photoemission spectroscopy (HARPES) at energies of about 3 keV. We present experimental data, as well as theoretical calculations, to understand the role of the Mn dopant in the emergence of ferromagnetism in this material. Both core-level spectra and angle-resolved or angle-integrated valence spectra are discussed. In particular, the HARPES experimental data are compared to free-electron final-state model calculations and to more accurate one-step photoemission theory. The experimental results show differences between Ga0.98Mn0.02P and GaP in both angle-resolved and angle-integrated valence spectra. The Ga0.98Mn0.02P bands are broadened due to the presence of Mn impurities that disturb the long-range translational order of the host GaP crystal. Mn-induced changes of the electronic structure are observed over the entire valence band range, including the presence of a distinct impurity band close to the valence-band maximum of the DMS. These experimental results are in good agreement with the one-step photoemission calculations and a prior HARPES study of Ga0.97Mn0.03As and GaAs [Gray et al., Nat. Mater. 11, 957 (2012)], demonstrating the strong similarity between these two materials. The Mn 2p and 3s core-level spectra also reveal an essentially identical state in doping both GaAs and GaP.

Published
2018
Full Text
View/download PDF

18. Band offsets in complex-oxide thin films and heterostructures of SrTiO3/LaNiO3 and SrTiO3/GdTiO3 by soft and hard X-ray photoelectron spectroscopy.

Author

Conti, G., Kaiser, A. M., Gray, A. X., Nemsˇák, S., Pálsson, G. K., Son, J., Moetakef, P., Janotti, A., Bjaalie, L., Conlon, C. S., Eiteneer, D., Greer, A. A., Keqi, A., Rattanachata, A., Saw, A. Y., Bostwick, A., Stolte, W. C., Gloskovskii, A., Drube, W., and Ueda, S.

Subjects
STRONTIUM titanate films, THIN film research, HETEROSTRUCTURES, PHOTOELECTRON spectroscopy, SURFACE charging
Abstract

The experimental determination of valence band offsets (VBOs) at interfaces in complex-oxide heterostructures using conventional soft x-ray photoelectron spectroscopy (SXPS, hν ≤ 1500 eV) and reference core-level binding energies can present challenges because of surface charging when photoelectrons are emitted and insufficient probing depth to clearly resolve the interfaces. In this paper, we compare VBOs measured with SXPS and its multi-keV hard x-ray analogue (HXPS, hν > 2000 eV). We demonstrate that the use of HXPS allows one to minimize charging effects and to probe more deeply buried interfaces in heterostructures such as SrTiO3/LaNiO3 and SrTiO3/GdTiO3. The VBO values obtained by HXPS for these interfaces are furthermore found to be close to those determined by first-principles calculations. [ABSTRACT FROM AUTHOR]

Published
2013
Full Text
View/download PDF

19. Electronic structure of the dilute magnetic semiconductor Ga1−xMnxP from hard x-ray photoelectron spectroscopy and angle-resolved photoemission

Author

Keqi, A., primary, Gehlmann, M., additional, Conti, G., additional, Nemšák, S., additional, Rattanachata, A., additional, Minár, J., additional, Plucinski, L., additional, Rault, J. E., additional, Rueff, J. P., additional, Scarpulla, M., additional, Hategan, M., additional, Pálsson, G. K., additional, Conlon, C., additional, Eiteneer, D., additional, Saw, A. Y., additional, Gray, A. X., additional, Kobayashi, K., additional, Ueda, S., additional, Dubon, O. D., additional, Schneider, C. M., additional, and Fadley, C. S., additional

Published
2018
Full Text
View/download PDF

20. The magnetization profile induced by the double magnetic proximity effect in an Fe/Fe0.30V0.70 superlattice.

Author

Palonen, H., Mukhamedov, B. O., Ponomareva, A. V., Pálsson, G. K., Abrikosov, I. A., and Hjörvarsson, B.

Subjects
MAGNETIZATION, NEUTRON reflectivity, ELECTRIC currents, DENSITY functional theory, MAGNETIZATION measurement
Abstract

The double magnetic proximity effect (MPE) in an Fe/Fe0.30V0.70 superlattice is studied by a direct measurement of the magnetization profile using polarized neutron reflectivity. The experimental magnetization profile is shown to qualitatively agree with a profile calculated using density functional theory. The profile is divided into a short range interfacial part and a long range tail. The interfacial part is explained by charge transfer and induced magnetization, while the tail is attributed to the inhomogeneous nature of the FeV alloy. The long range tail in the magnetization persists up to 170% above the intrinsic ordering temperature of the FeV alloy. The observed effects can be used to design systems with a direct exchange coupling between layers over long distances through a network of connected atoms. When combined with the recent advances in tuning and switching, the MPE with electric fields and currents, the results can be applied in spintronic devices. [ABSTRACT FROM AUTHOR]

Published
2019
Full Text
View/download PDF

21. Temperature responsive lipid liquid crystal layers with embedded nanogels

Author

Dabkowska, A. P., primary, Hirst, C., additional, Valldeperas, M., additional, Clifton, L. A., additional, Montis, C., additional, Nöjd, S., additional, Gentile, L., additional, Wang, M., additional, Pálsson, G. K., additional, Lages, S., additional, Berti, D., additional, Barauskas, J., additional, and Nylander, T., additional

Published
2017
Full Text
View/download PDF

26. Mg/Ti multilayers: Structural and hydrogen absorption properties

Author

Wijngaarden, R.J., Baldi, A., Pálsson, G. K., Gonzalez-Silveira, M., Schreuders, H., Slaman, M.J., Rector, J.H., Krishnan, G., Kooi, B.J., Walker, G. S., Fay, M. W., Hjörvarsson, B., Dam, B., Griessen, R.P., Wijngaarden, R.J., Baldi, A., Pálsson, G. K., Gonzalez-Silveira, M., Schreuders, H., Slaman, M.J., Rector, J.H., Krishnan, G., Kooi, B.J., Walker, G. S., Fay, M. W., Hjörvarsson, B., Dam, B., and Griessen, R.P.

Abstract

Mg-Ti alloys have uncommon optical and hydrogen absorbing properties, originating from a "spinodal-like" microstructure with a small degree of chemical short-range order in the atomic distribution. In the present study we artificially engineer short-range order by depositing Pd-capped Mg/Ti multilayers with different periodicities. Notwithstanding the large lattice mismatch between Mg and Ti, the as-deposited metallic multilayers show good structural coherence. On exposure to H2 gas a two-step hydrogenation process occurs with the Ti layers forming the hydride before Mg. From in situ measurements of the bilayer thickness Λ at different hydrogen pressures, we observe large out-of-plane expansions of Mg and Ti layers on hydrogenation, indicating strong plastic deformations in the films and a consequent shortening of the coherence length. On unloading at room temperature in air, hydrogen atoms remain trapped in the Ti layers due to kinetic constraints. Such loading/unloading sequence can be explained in terms of the different thermodynamic properties of hydrogen in Mg and Ti, as shown by diffusion calculations on a model multilayered systems. Absorption isotherms measured by hydrogenography can be interpreted as a result of the elastic clamping arising from strongly bonded Mg/Pd and broken Mg/Ti interfaces. © 2010 The American Physical Society.

Published
2010
Full Text
View/download PDF

30. Saturated ablation in metal hydrides and acceleration of protons and deuterons to keV energies with a soft-x-ray laser

Author

Andreasson, J., primary, Iwan, B., additional, Andrejczuk, A., additional, Abreu, E., additional, Bergh, M., additional, Caleman, C., additional, Nelson, A. J., additional, Bajt, S., additional, Chalupsky, J., additional, Chapman, H. N., additional, Fäustlin, R. R., additional, Hajkova, V., additional, Heimann, P. A., additional, Hjörvarsson, B., additional, Juha, L., additional, Klinger, D., additional, Krzywinski, J., additional, Nagler, B., additional, Pálsson, G. K., additional, Singer, W., additional, Seibert, M. M., additional, Sobierajski, R., additional, Toleikis, S., additional, Tschentscher, T., additional, Vinko, S. M., additional, Lee, R. W., additional, Hajdu, J., additional, and Tîmneanu, N., additional

Published
2011
Full Text
View/download PDF

31. Mg/Ti multilayers: Structural and hydrogen absorption properties

Author

Baldi, A., primary, Pálsson, G. K., additional, Gonzalez-Silveira, M., additional, Schreuders, H., additional, Slaman, M., additional, Rector, J. H., additional, Krishnan, G., additional, Kooi, B. J., additional, Walker, G. S., additional, Fay, M. W., additional, Hjörvarsson, B., additional, Wijngaarden, R. J., additional, Dam, B., additional, and Griessen, R., additional

Published
2010
Full Text
View/download PDF

39. Long-range antiferromagnetic order in epitaxial Mn2GaC thin films from neutron reflectometry.

Author

Ingason, A. S., Pálsson, G. K., Dahlqvist, M., and Rosen, J.

Subjects
*ANTIFERROMAGNETISM, *MANGANESE compounds, *NEUTRON reflectometry
Abstract

The nature of the magnetic structure in magnetic so-called MAX phases is a topic of some controversy. Here we present unpolarized neutron-diffraction data between 3.4 and 290.0 K and momentum transfer between Q=0.0and1.1 Å-1, as well as complementary x-ray-diffraction data on epitaxial thin films of the MAX phase material Mn2GaC. This inherently layered material exhibits neutron-diffraction peaks consistent with long-ranged antiferromagnetic order with a periodicity of two structural unit cells. The magnetic structure is present throughout the measured temperature range. The results are in agreement with first-principles calculations of antiferromagnetic structures for this material where the Mn-C-Mn atomic trilayers are found to be ferromagnetically coupled internally but spin flipped or rotated across the Ga layers. The present findings have significant bearing on the discussion regarding the nature of the magnetic structure in magnetic MAX phases. [ABSTRACT FROM AUTHOR]

Published
2016
Full Text
View/download PDF

40. Beneficial effects of a Paleolithic diet on cardiovascular risk factors in type 2 diabetes: a randomized cross-over pilot study

Author

Hansson Anita, Pålsson Gunvor, Branell Ulla-Carin, Ahrén Bo, Granfeldt Yvonne, Jönsson Tommy, Söderström Margareta, and Lindeberg Staffan

Subjects
Diseases of the circulatory (Cardiovascular) system, RC666-701
Abstract

Abstract Background Our aim was to compare the effects of a Paleolithic ('Old Stone Age') diet and a diabetes diet as generally recommended on risk factors for cardiovascular disease in patients with type 2 diabetes not treated with insulin. Methods In a randomized cross-over study, 13 patients with type 2 diabetes, 3 women and 10 men, were instructed to eat a Paleolithic diet based on lean meat, fish, fruits, vegetables, root vegetables, eggs and nuts; and a Diabetes diet designed in accordance with dietary guidelines during two consecutive 3-month periods. Outcome variables included changes in weight, waist circumference, serum lipids, C-reactive protein, blood pressure, glycated haemoglobin (HbA1c), and areas under the curve for plasma glucose and plasma insulin in the 75 g oral glucose tolerance test. Dietary intake was evaluated by use of 4-day weighed food records. Results Study participants had on average a diabetes duration of 9 years, a mean HbA1c of 6,6% units by Mono-S standard and were usually treated with metformin alone (3 subjects) or metformin in combination with a sulfonylurea (3 subjects) or a thiazolidinedione (3 subjects). Mean average dose of metformin was 1031 mg per day. Compared to the diabetes diet, the Paleolithic diet resulted in lower mean values of HbA1c (-0.4% units, p = 0.01), triacylglycerol (-0.4 mmol/L, p = 0.003), diastolic blood pressure (-4 mmHg, p = 0.03), weight (-3 kg, p = 0.01), BMI (-1 kg/m2, p = 0.04) and waist circumference (-4 cm, p = 0.02), and higher mean values of high density lipoprotein cholesterol (+0.08 mmol/L, p = 0.03). The Paleolithic diet was mainly lower in cereals and dairy products, and higher in fruits, vegetables, meat and eggs, as compared with the Diabetes diet. Further, the Paleolithic diet was lower in total energy, energy density, carbohydrate, dietary glycemic load, saturated fatty acids and calcium, and higher in unsaturated fatty acids, dietary cholesterol and several vitamins. Dietary GI was slightly lower in the Paleolithic diet (GI = 50) than in the Diabetic diet (GI = 55). Conclusion Over a 3-month study period, a Paleolithic diet improved glycemic control and several cardiovascular risk factors compared to a Diabetes diet in patients with type 2 diabetes. Trial registration ClinicalTrials.gov NCT00435240.

Published
2009
Full Text
View/download PDF

43. Reversible exchange bias in epitaxial V 2 O 3 /Ni hybrid magnetic heterostructures.

Author

Ignatova K, Thorsteinsson EB, Jósteinsson BA, Strandqvist N, Vantaraki C, Kapaklis V, Devishvili A, Pálsson GK, and Arnalds UB

Abstract

In this work we present a temperature and angular dependent study of the structural and magnetic properties in highly crystalline V 2 O 3 /Ni/Zr magnetic heterostructure films. Our investigation focuses on the coupling between the ferromagnetic Ni layer and V 2 O 3 layer which undergoes an antiferromagnetic/paramagnetic phase transition coupled to the structural phase transition of the material at around 150 K. Structural investigations using x-ray diffraction reveal highly crystalline films of a quality which has previously not been reported in the literature. The Ni layers display an absence of in-plane magnetic anisotropy owing to the highly textured (1 1 1) layering of the Ni films on the underlying V 2 O 3 (0 0 0 1) oriented layer. During the transition we observe a strain related enhancement of the coercivity and the onset of a weak exchange bias for cooling under an external magnetic field. Heating the films to above the transition temperature, the exchange bias in the Ni is removed and can be reversed upon subsequent cooling under an inverted external magnetic field. Using temperature dependent polarized neutron reflectometry we investigate the film structure at the interface, capturing the magnetic and nuclear profiles., (© 2022 IOP Publishing Ltd.)

Published
2022
Full Text
View/download PDF

44. Associations of autozygosity with a broad range of human phenotypes.

Author

Clark DW, Okada Y, Moore KHS, Mason D, Pirastu N, Gandin I, Mattsson H, Barnes CLK, Lin K, Zhao JH, Deelen P, Rohde R, Schurmann C, Guo X, Giulianini F, Zhang W, Medina-Gomez C, Karlsson R, Bao Y, Bartz TM, Baumbach C, Biino G, Bixley MJ, Brumat M, Chai JF, Corre T, Cousminer DL, Dekker AM, Eccles DA, van Eijk KR, Fuchsberger C, Gao H, Germain M, Gordon SD, de Haan HG, Harris SE, Hofer E, Huerta-Chagoya A, Igartua C, Jansen IE, Jia Y, Kacprowski T, Karlsson T, Kleber ME, Li SA, Li-Gao R, Mahajan A, Matsuda K, Meidtner K, Meng W, Montasser ME, van der Most PJ, Munz M, Nutile T, Palviainen T, Prasad G, Prasad RB, Priyanka TDS, Rizzi F, Salvi E, Sapkota BR, Shriner D, Skotte L, Smart MC, Smith AV, van der Spek A, Spracklen CN, Strawbridge RJ, Tajuddin SM, Trompet S, Turman C, Verweij N, Viberti C, Wang L, Warren HR, Wootton RE, Yanek LR, Yao J, Yousri NA, Zhao W, Adeyemo AA, Afaq S, Aguilar-Salinas CA, Akiyama M, Albert ML, Allison MA, Alver M, Aung T, Azizi F, Bentley AR, Boeing H, Boerwinkle E, Borja JB, de Borst GJ, Bottinger EP, Broer L, Campbell H, Chanock S, Chee ML, Chen G, Chen YI, Chen Z, Chiu YF, Cocca M, Collins FS, Concas MP, Corley J, Cugliari G, van Dam RM, Damulina A, Daneshpour MS, Day FR, Delgado GE, Dhana K, Doney ASF, Dörr M, Doumatey AP, Dzimiri N, Ebenesersdóttir SS, Elliott J, Elliott P, Ewert R, Felix JF, Fischer K, Freedman BI, Girotto G, Goel A, Gögele M, Goodarzi MO, Graff M, Granot-Hershkovitz E, Grodstein F, Guarrera S, Gudbjartsson DF, Guity K, Gunnarsson B, Guo Y, Hagenaars SP, Haiman CA, Halevy A, Harris TB, Hedayati M, van Heel DA, Hirata M, Höfer I, Hsiung CA, Huang J, Hung YJ, Ikram MA, Jagadeesan A, Jousilahti P, Kamatani Y, Kanai M, Kerrison ND, Kessler T, Khaw KT, Khor CC, de Kleijn DPV, Koh WP, Kolcic I, Kraft P, Krämer BK, Kutalik Z, Kuusisto J, Langenberg C, Launer LJ, Lawlor DA, Lee IT, Lee WJ, Lerch MM, Li L, Liu J, Loh M, London SJ, Loomis S, Lu Y, Luan J, Mägi R, Manichaikul AW, Manunta P, Másson G, Matoba N, Mei XW, Meisinger C, Meitinger T, Mezzavilla M, Milani L, Millwood IY, Momozawa Y, Moore A, Morange PE, Moreno-Macías H, Mori TA, Morrison AC, Muka T, Murakami Y, Murray AD, de Mutsert R, Mychaleckyj JC, Nalls MA, Nauck M, Neville MJ, Nolte IM, Ong KK, Orozco L, Padmanabhan S, Pálsson G, Pankow JS, Pattaro C, Pattie A, Polasek O, Poulter N, Pramstaller PP, Quintana-Murci L, Räikkönen K, Ralhan S, Rao DC, van Rheenen W, Rich SS, Ridker PM, Rietveld CA, Robino A, van Rooij FJA, Ruggiero D, Saba Y, Sabanayagam C, Sabater-Lleal M, Sala CF, Salomaa V, Sandow K, Schmidt H, Scott LJ, Scott WR, Sedaghati-Khayat B, Sennblad B, van Setten J, Sever PJ, Sheu WH, Shi Y, Shrestha S, Shukla SR, Sigurdsson JK, Sikka TT, Singh JR, Smith BH, Stančáková A, Stanton A, Starr JM, Stefansdottir L, Straker L, Sulem P, Sveinbjornsson G, Swertz MA, Taylor AM, Taylor KD, Terzikhan N, Tham YC, Thorleifsson G, Thorsteinsdottir U, Tillander A, Tracy RP, Tusié-Luna T, Tzoulaki I, Vaccargiu S, Vangipurapu J, Veldink JH, Vitart V, Völker U, Vuoksimaa E, Wakil SM, Waldenberger M, Wander GS, Wang YX, Wareham NJ, Wild S, Yajnik CS, Yuan JM, Zeng L, Zhang L, Zhou J, Amin N, Asselbergs FW, Bakker SJL, Becker DM, Lehne B, Bennett DA, van den Berg LH, Berndt SI, Bharadwaj D, Bielak LF, Bochud M, Boehnke M, Bouchard C, Bradfield JP, Brody JA, Campbell A, Carmi S, Caulfield MJ, Cesarini D, Chambers JC, Chandak GR, Cheng CY, Ciullo M, Cornelis M, Cusi D, Smith GD, Deary IJ, Dorajoo R, van Duijn CM, Ellinghaus D, Erdmann J, Eriksson JG, Evangelou E, Evans MK, Faul JD, Feenstra B, Feitosa M, Foisy S, Franke A, Friedlander Y, Gasparini P, Gieger C, Gonzalez C, Goyette P, Grant SFA, Griffiths LR, Groop L, Gudnason V, Gyllensten U, Hakonarson H, Hamsten A, van der Harst P, Heng CK, Hicks AA, Hochner H, Huikuri H, Hunt SC, Jaddoe VWV, De Jager PL, Johannesson M, Johansson Å, Jonas JB, Jukema JW, Junttila J, Kaprio J, Kardia SLR, Karpe F, Kumari M, Laakso M, van der Laan SW, Lahti J, Laudes M, Lea RA, Lieb W, Lumley T, Martin NG, März W, Matullo G, McCarthy MI, Medland SE, Merriman TR, Metspalu A, Meyer BF, Mohlke KL, Montgomery GW, Mook-Kanamori D, Munroe PB, North KE, Nyholt DR, O'connell JR, Ober C, Oldehinkel AJ, Palmas W, Palmer C, Pasterkamp GG, Patin E, Pennell CE, Perusse L, Peyser PA, Pirastu M, Polderman TJC, Porteous DJ, Posthuma D, Psaty BM, Rioux JD, Rivadeneira F, Rotimi C, Rotter JI, Rudan I, Den Ruijter HM, Sanghera DK, Sattar N, Schmidt R, Schulze MB, Schunkert H, Scott RA, Shuldiner AR, Sim X, Small N, Smith JA, Sotoodehnia N, Tai ES, Teumer A, Timpson NJ, Toniolo D, Tregouet DA, Tuomi T, Vollenweider P, Wang CA, Weir DR, Whitfield JB, Wijmenga C, Wong TY, Wright J, Yang J, Yu L, Zemel BS, Zonderman AB, Perola M, Magnusson PKE, Uitterlinden AG, Kooner JS, Chasman DI, Loos RJF, Franceschini N, Franke L, Haley CS, Hayward C, Walters RG, Perry JRB, Esko T, Helgason A, Stefansson K, Joshi PK, Kubo M, and Wilson JF

Subjects
Alleles, Haplotypes, Homozygote, Humans, Body Size genetics, Cognition, Consanguinity, Fertility genetics, Health Status, Inbreeding Depression genetics, Risk-Taking
Abstract

In many species, the offspring of related parents suffer reduced reproductive success, a phenomenon known as inbreeding depression. In humans, the importance of this effect has remained unclear, partly because reproduction between close relatives is both rare and frequently associated with confounding social factors. Here, using genomic inbreeding coefficients (F ROH ) for >1.4 million individuals, we show that F ROH is significantly associated (p < 0.0005) with apparently deleterious changes in 32 out of 100 traits analysed. These changes are associated with runs of homozygosity (ROH), but not with common variant homozygosity, suggesting that genetic variants associated with inbreeding depression are predominantly rare. The effect on fertility is striking: F ROH equivalent to the offspring of first cousins is associated with a 55% decrease [95% CI 44-66%] in the odds of having children. Finally, the effects of F ROH are confirmed within full-sibling pairs, where the variation in F ROH is independent of all environmental confounding.

Published
2019
Full Text
View/download PDF

45. Multiple transmissions of de novo mutations in families.

Author

Jónsson H, Sulem P, Arnadottir GA, Pálsson G, Eggertsson HP, Kristmundsdottir S, Zink F, Kehr B, Hjorleifsson KE, Jensson BÖ, Jonsdottir I, Marelsson SE, Gudjonsson SA, Gylfason A, Jonasdottir A, Jonasdottir A, Stacey SN, Magnusson OT, Thorsteinsdottir U, Masson G, Kong A, Halldorsson BV, Helgason A, Gudbjartsson DF, and Stefansson K

Subjects
Adult, Child, Embryonic Germ Cells metabolism, Family Characteristics, Female, Germ-Line Mutation, Humans, Male, Mosaicism, Pedigree, Family, Inheritance Patterns genetics, Mutation, Parent-Child Relations
Abstract

De novo mutations (DNMs) cause a large proportion of severe rare diseases of childhood. DNMs that occur early may result in mosaicism of both somatic and germ cells. Such early mutations can cause recurrence of disease. We scanned 1,007 sibling pairs from 251 families and identified 878 DNMs shared by siblings (ssDNMs) at 448 genomic sites. We estimated DNM recurrence probability based on parental mosaicism, sharing of DNMs among siblings, parent-of-origin, mutation type and genomic position. We detected 57.2% of ssDNMs in the parental blood. The recurrence probability of a DNM decreases by 2.27% per year for paternal DNMs and 1.78% per year for maternal DNMs. Maternal ssDNMs are more likely to be T>C mutations than paternal ssDNMs, and less likely to be C>T mutations. Depending on the properties of the DNM, the recurrence probability ranges from 0.011% to 28.5%. We have launched an online calculator to allow estimation of DNM recurrence probability for research purposes.

Published
2018
Full Text
View/download PDF

46. Temperature dependence of the electrical resistivity and electronic structure of amorphous Fe100-xZrx films and multilayers.

Author

Kapaklis V, Pálsson GK, Vegelius J, Haverhals MM, Korelis PT, Butorin SM, Modin A, Kavčič M, Zitnik M, Bučar K, Kvashnina KO, and Hjörvarsson B

Abstract

The electrical resistivity of amorphous Fe(100-x)Zr(x) metal alloy films and multilayers has been investigated in a wide temperature and composition range. The overall behavior of the resistivity is consistent with bulk measurements, exhibiting prominent semiconductor-like changes at low temperatures. The transition from positive (metallic) to negative temperature coefficient of resistivity behavior is accompanied by minute changes in magnetoresistance and we can therefore rule out magnetic phase changes as being the cause for the observed changes in the resistivity. Using x-ray absorption and emission spectroscopies we are able to probe the unoccupied and occupied electronic densities of states. The corresponding spectra are found to significantly overlap, as expected for a metallic-like electronic structure and the absence of a band gap. Besides a broadening of the x-ray emission lines expected from an amorphous material, remarkably small differences are observed in the electronic structures when changing the amount of Zr. The resistivity data were modeled and agreement with the Mott variable range hopping model was found, indicating localized electronic states due the disordered structure of the Fe(100-x)Zr(x) alloys.

Published
2012
Full Text
View/download PDF

47. Increasing incidence of late-onset neonatal invasive group B streptococcal infections in Iceland.

Author

Óladóttir GL, Erlendsdóttir H, Pálsson G, Björnsdóttir ES, Kristinsson KG, and Haraldsson Á

Subjects
Blood microbiology, Cerebrospinal Fluid microbiology, Female, Humans, Iceland epidemiology, Incidence, Infant, Infant, Newborn, Male, Retrospective Studies, Serotyping, Streptococcal Infections mortality, Streptococcus agalactiae classification, Streptococcal Infections epidemiology, Streptococcal Infections microbiology, Streptococcus agalactiae isolation & purification
Abstract

Background: Group B streptococci (GBS) may cause life-threatening invasive infections in infants. The incidence of these infections has been increasing during the last decades. The aim of the study was to determine the epidemiology of neonatal GBS infections to be able to implement therapeutic and preventive measures more effectively., Methods: A retrospective case study was conducted in Iceland that included all neonates with positive GBS cultures from blood or cerebrospinal fluid during the period 1975 to 2006. Serotyping of all available GBS isolates was performed., Results: A total of 87 children with 89 infections were included in the study. In all, 53 infants had early-onset (EO) GBS infections (occurring <7 days after birth) and 34 had late-onset (LO) infections (occurring on days 7-90). EO infections increased during the first 3 quartiles of the study period but decreased during the last quartile. LO infections increased throughout the entire study period. GBS was cultured from cerebrospinal fluid in 21 patients; 9 with EO and 12 with LO infections. Premature infants comprised 15 with EO and 14 with LO infections. Eight children died of GBS infection, 7 with EO and 1 with LO infections; no correlation with serotypes was found. Serotype III was most common for both EO (34%) and LO infections (62%)., Conclusion: The number of GBS infections increased during the study period. The decrease in EO infections in recent years could be attributed to intrapartum antibiotic treatment. The increasing number of LO infections is a concern.

Published
2011
Full Text
View/download PDF

48. Genomic anthropology: coming in from the cold?

Author

Pálsson G

Subjects
Canada, Epigenesis, Genetic, History, 20th Century, History, 21st Century, Humans, Inuit genetics, Anthropology, Cultural history, Inuit history
Abstract

By rendering obsolete the theoretical opposition of nature and culture, the study of the human genome has given rise to fresh networks among anthropologists and other scholars. These developments, in turn, invite a refashioning of anthropology. Because genomic studies are directly concerned with the constitution of personhood, they must engage with local notions of personhood and belonging, thus undermining the distinction between experts and laypersons and demonstrating the need for new frameworks for collaboration between anthropologists and their subjects. These trends are illustrated by research in Nunavut (Canada) and Greenland, in particular an examination of the similarities and differences between modern gene talk about the constitution of the individual and "Inuit epigenetics"--local notions of naming, subjectivity, and relatedness.

Published
2008

49. [Hyponatremia in very low birth weight infants].

Author

Gudmundsson K, Thórkelsson T, Pálsson G, Bergsteinsson H, Kjartansson S, Haraldsson A, and Dagbjartsson A

Subjects
Birth Weight, Fluid Therapy, Gestational Age, Humans, Hyponatremia metabolism, Hyponatremia prevention & control, Iceland, Infant, Newborn, Intensive Care Units, Neonatal, Kidney growth & development, Retrospective Studies, Risk Factors, Sodium blood, Sodium urine, Time Factors, Weight Loss, Hyponatremia etiology, Infant, Very Low Birth Weight, Kidney metabolism, Sodium metabolism
Abstract

Aim: Hyponatremia can potentially have serious effects in the premature infant, Therefore, it is important to recognize its causes and prevent it if possible. The aim of this study was to evaluate the causes of hyponatremia in very low birth weight (VLBW) infants cared for at the Neonatal Intensive Care Unit (NICU) of Children's Hospital Iceland., Subjects and Methods: Retrospective descriptive study of 20 VLBW infants at the NICU of Children's Hospital Iceland, born after <30 weeks gestation with birth weight of < or =1250 g. Information was obtained on fluid administration, weight loss, sodium administration and serum sodium concentrations during their first ten days of life., Results: The median gestational age was 27 weeks (24-29 weeks) and the median birth weight was 905 g (620-1250 g). A negative correlation was found between birth weight and the amount of fluids given (R2=-0.42; p=0.002). The median weight loss was 10.6% (3.1-29.5%). A positive correlation was found between weight loss and the amount of fluids the infants received (R2=0.76; p<0.001). The amount of sodium given was on the average 5.7+3.1 mmól/kg/24 hours. The median serum sodium concentration was 137 mmól/L (127-150 mmól/L). A negative correlation was found between the amount of sodium given and serum sodium concentrations (R2=-0.42; p<0.001). There was no correlation between the amount of fluids given and serum sodium concentrations (R2=0.006; p=0.7). A negative correlation was found between birth weight and serum sodium concentrations (R2=-0.24; p=0.027)., Conclusion: High sodium requirements in VLBW infants at our hospital suggests that their hyponatremia is mainly due to the immaturity of their kidneys, which is known to result in excessive loss of sodium in the urine.

Published
2008

50. [Viral hepatitis B and C among immigrants in Iceland].

Author

Jónsdóttir G, Briem H, Blöndal T, Pálsson G, Olafsson S, and Gudnason T

Subjects
Adolescent, Adult, Africa ethnology, Age Distribution, Aged, Aged, 80 and over, Asia ethnology, Child, Child, Preschool, Europe, Eastern ethnology, Hepatitis Antibodies blood, Hepatitis B enzymology, Hepatitis B virology, Hepatitis C enzymology, Hepatitis C virology, Humans, Iceland epidemiology, Infant, Infant, Newborn, Middle Aged, Prevalence, Registries statistics & numerical data, Seroepidemiologic Studies, Time Factors, Transaminases blood, Emigration and Immigration statistics & numerical data, Endemic Diseases statistics & numerical data, Hepatitis B epidemiology, Hepatitis C epidemiology, Mass Screening
Abstract

Background: Viral hepatitis B and C are a major health problem worldwide. The prevalence of these diseases varies throughout the world. In Iceland, the incidence of hepatitis B and C has increased in recent years. At the same time, the number of immigrants from countries where viral hepatitis is endemic, has also increased. The aim of this study was to investigate the epidemiology of hepatitis B and C among immigrants in Iceland., Material and Methods: Immigrants from outside the European Economic Area (EEA) were screened for hepatitis B and C. Medical records for the years 2000-2002 were reviewed for country of origin, viral serology and liver transaminases. Information was gathered from the State Epidemiologist's central registry of notifiable diseases and from the Icelandic Directorate of Immigration on the number of residence permits issued., Results: 70% of all immigrants from countries outside the EEA during the study period were included in the study. Blood samples were obtained from 2946 immigrants. 83 (2.8%) had hepatitis B and 24 (0.8%) had hepatitis C. Prevalence of hepatitis B was highest among immigrants from Africa,11/171 (6.4%; 95% CI: 3.3-11.2%) and hepatitis C among immigrants from Eastern Europe, 16/1502 (1.1%; 95% CI: 0.6-1.7%). 482 (16%) had serological markers of previous hepatitis B infection. Of all registered cases of hepatitis B, immigrants were 56% and of hepatitis C 10%., Conclusions: 1. Majority of those diagnosed with hepatitis B during the study period were immigrants. 2. Among immigrants, hepatitis B was more prevalent than hepatitis C. 3) The high prevalence of hepatitis B justifies screening for the disease in this population.

Published
2006

Catalog

Books, media, physical & digital resources
See catalog results