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Institution

University of Groningen

EducationGroningen, Groningen, Netherlands
About: University of Groningen is a education organization based out in Groningen, Groningen, Netherlands. It is known for research contribution in the topics: Population & Poison control. The organization has 36346 authors who have published 69116 publications receiving 2940370 citations. The organization is also known as: Rijksuniversiteit Groningen & RUG.


Papers
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Journal ArticleDOI
TL;DR: The duration of subsequent stride cycles and left/right steps, and estimations of step length and walking speed can be obtained from lower trunk accelerations, which can be the basis for an analysis of other signals within the stride cycle.

757 citations

Journal ArticleDOI
Kazunori Akiyama, Antxon Alberdi1, Walter Alef2, Keiichi Asada3  +394 moreInstitutions (78)
TL;DR: The Event Horizon Telescope (EHT) as mentioned in this paper is a very long baseline interferometry (VLBI) array that comprises millimeter and submillimeter-wavelength telescopes separated by distances comparable to the diameter of the Earth.
Abstract: The Event Horizon Telescope (EHT) is a very long baseline interferometry (VLBI) array that comprises millimeter- and submillimeter-wavelength telescopes separated by distances comparable to the diameter of the Earth. At a nominal operating wavelength of ~1.3 mm, EHT angular resolution (λ/D) is ~25 μas, which is sufficient to resolve nearby supermassive black hole candidates on spatial and temporal scales that correspond to their event horizons. With this capability, the EHT scientific goals are to probe general relativistic effects in the strong-field regime and to study accretion and relativistic jet formation near the black hole boundary. In this Letter we describe the system design of the EHT, detail the technology and instrumentation that enable observations, and provide measures of its performance. Meeting the EHT science objectives has required several key developments that have facilitated the robust extension of the VLBI technique to EHT observing wavelengths and the production of instrumentation that can be deployed on a heterogeneous array of existing telescopes and facilities. To meet sensitivity requirements, high-bandwidth digital systems were developed that process data at rates of 64 gigabit s^(−1), exceeding those of currently operating cm-wavelength VLBI arrays by more than an order of magnitude. Associated improvements include the development of phasing systems at array facilities, new receiver installation at several sites, and the deployment of hydrogen maser frequency standards to ensure coherent data capture across the array. These efforts led to the coordination and execution of the first Global EHT observations in 2017 April, and to event-horizon-scale imaging of the supermassive black hole candidate in M87.

756 citations

Journal ArticleDOI
TL;DR: In this article, a systematic analysis is performed on the effectiveness of removing degrees of freedom from hydrogen atoms and increasing hydrogen masses to increase the efficiency of molecular dynamics simulations of hydrogen-rich systems.
Abstract: A systematic analysis is performed on the effectiveness of removing degrees of freedom from hydrogen atoms andror increasing hydrogen masses to increase the efficiency of molecular dynamics simulations of hydrogen-rich systems such as proteins in water. In proteins, high-frequency bond-angle vibrations involving hydrogen atoms limit the time step to 3 fs, which is already a factor of 1.5 beyond the commonly used time step of 2 fs. Removing these degrees of freedom from the system by constructing hydrogen atoms as dummy atoms, allows the time step to be increased to 7 fs, a factor of 3.5 compared with 2 fs. Additionally, a gain in simulation stability can be achieved by increasing the masses of hydrogen atoms with remaining degrees of freedom from 1 to 4 u. Increasing hydrogen mass without removing the high-frequency degrees of freedom allows the time step to be increased only to 4 fs, a factor of two, compared with 2 fs. The net gain in efficiency of sampling configurational space may be up to 15% lower than expected from the increase in time step due to the increase in viscosity and decrease in diffusion constant. In principle, introducing dummy atoms and increasing hydrogen mass do not influence thermodynamical properties of the system and dynamical properties are shown to be influenced only to a moderate degree. Comparing the maximum . time step attainable with these methods 7 fs to the time step of 2 fs that is routinely used in simulation, and taking into account the increase in viscosity and decrease in diffusion constant, we can say that a net gain in simulation efficiency of a factor of 3 to 3.5 can be achieved. Q 1999 John Wiley & Sons, Inc. J Comput Chem 20: 786)798, 1999

755 citations

Journal ArticleDOI
Daniel F. Gudbjartsson1, Unnur S. Bjornsdottir1, Unnur S. Bjornsdottir2, Eva Halapi1, Anna Helgadottir1, Patrick Sulem1, Gudrun M. Jonsdottir1, Gudmar Thorleifsson1, Hafdis T. Helgadottir1, Valgerdur Steinthorsdottir1, Hreinn Stefansson1, Carolyn Williams3, Jennie Hui3, John Beilby3, Nicole M. Warrington3, Alan L. James3, Alan L. James4, Lyle J. Palmer3, Gerard H. Koppelman5, Andrea Heinzmann6, Marcus Krueger6, H. Marike Boezen7, Amanda Wheatley8, Janine Altmüller9, Hyoung Doo Shin10, Soo-Taek Uh11, Hyun Sub Cheong11, Brynja Jonsdottir, David Gislason, Choon-Sik Park11, Linda M. Rasmussen12, Celeste Porsbjerg12, Jakob Werner Hansen12, Vibeke Backer12, Thomas Werge, Christer Janson13, Ulla-Britt Jönsson13, Maggie C.Y. Ng14, Juliana C.N. Chan14, Wing-Yee So14, Ronald C.W. Ma14, Svati H. Shah15, Christopher B. Granger15, Arshed A. Quyyumi16, Allan I. Levey16, Viola Vaccarino16, Muredach P. Reilly17, Daniel J. Rader17, Michael J.A. Williams18, Andre M. van Rij18, Gregory T. Jones18, Elisabetta Trabetti19, Giovanni Malerba19, Pier Franco Pignatti19, Attilio Boner19, Lydia Pescollderungg, Domenico Girelli19, Oliviero Olivieri19, Nicola Martinelli19, Bjorn R. Ludviksson2, Dora Ludviksdottir, Gudmundur I. Eyjolfsson, David O. Arnar2, Gudmundur Thorgeirsson2, Klaus A. Deichmann6, Philip J. Thompson3, Matthias Wjst, Ian P. Hall9, Dirkje S. Postma7, Thorarinn Gislason2, Jeffrey R. Gulcher1, Augustine Kong1, Ingileif Jonsdottir2, Ingileif Jonsdottir1, Unnur Thorsteinsdottir2, Unnur Thorsteinsdottir1, Kari Stefansson1, Kari Stefansson2 
TL;DR: A genome-wide association scan for sequence variants affecting eosinophil counts in blood of 9,392 Icelanders found that a nonsynonymous SNP at 12q24, in SH2B3, associated significantly with myocardial infarction in six different populations.
Abstract: Eosinophils are pleiotropic multifunctional leukocytes involved in initiation and propagation of inflammatory responses and thus have important roles in the pathogenesis of inflammatory diseases. Here we describe a genome-wide association scan for sequence variants affecting eosinophil counts in blood of 9,392 Icelanders. The most significant SNPs were studied further in 12,118 Europeans and 5,212 East Asians. SNPs at 2q12 (rs1420101), 2q13 (rs12619285), 3q21 (rs4857855), 5q31 (rs4143832) and 12q24 (rs3184504) reached genome-wide significance (P = 5.3 x 10(-14), 5.4 x 10(-10), 8.6 x 10(-17), 1.2 x 10(-10) and 6.5 x 10(-19), respectively). A SNP at IL1RL1 associated with asthma (P = 5.5 x 10(-12)) in a collection of ten different populations (7,996 cases and 44,890 controls). SNPs at WDR36, IL33 and MYB that showed suggestive association with eosinophil counts were also associated with atopic asthma (P = 4.2 x 10(-6), 2.2 x 10(-5) and 2.4 x 10(-4), respectively). We also found that a nonsynonymous SNP at 12q24, in SH2B3, associated significantly (P = 8.6 x 10(-8)) with myocardial infarction in six different populations (6,650 cases and 40,621 controls).

754 citations

Journal ArticleDOI
17 Dec 1999-Science
TL;DR: It is shown that vancomycin and the antibacterial peptide nisin Z use the same target: the membrane-anchored cell wall precursor Lipid II, thus causing the peptide to be highly active (in the nanomolar range).
Abstract: Resistance to antibiotics is increasing in some groups of clinically important pathogens. For instance, high vancomycin resistance has emerged in enterococci. Promising alternative antibiotics are the peptide antibiotics, abundant in host defense systems, which kill their targets by permeabilizing the plasma membrane. These peptides generally do not act via specific receptors and are active in the micromolar range. Here it is shown that vancomycin and the antibacterial peptide nisin Z use the same target: the membrane-anchored cell wall precursor Lipid II. Nisin combines high affinity for Lipid II with its pore-forming ability, thus causing the peptide to be highly active (in the nanomolar range).

754 citations


Authors

Showing all 36692 results

NameH-indexPapersCitations
Ronald C. Kessler2741332328983
Nicholas J. Wareham2121657204896
André G. Uitterlinden1991229156747
Lei Jiang1702244135205
Brenda W.J.H. Penninx1701139119082
Richard H. Friend1691182140032
Panos Deloukas162410154018
Jerome I. Rotter1561071116296
Christopher M. Dobson1501008105475
Dirk Inzé14964774468
Scott T. Weiss147102574742
Dieter Lutz13967167414
Wilmar B. Schaufeli13751395718
Cisca Wijmenga13666886572
Arnold B. Bakker135506103778
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Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
2023166
2022543
20214,487
20203,990
20193,283
20182,836