Search Results - "Viljanen, A"

Rapid Geomagnetic Variations During High‐Speed Stream, Sheath and Magnetic Cloud‐Driven Geomagnetic Storms From 1996 to 2023 by Pedersen, M. N., Juusola, L., Vanhamäki, H., Aikio, A. T., Viljanen, A.

“…The most detrimental geomagnetically induced currents (GICs) documented to date have all taken place during geomagnetic storms. Yet, the probability of GICs…”
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The association between objectively measured physical activity and life-space mobility among older people by Tsai, L.-T., Portegijs, E., Rantakokko, M., Viljanen, A., Saajanaho, M., Eronen, J., Rantanen, T.

“…The purpose of this cross‐sectional study was to investigate the association between objectively measured physical activity and life‐space mobility in…”
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Auroral Omega Bands are a Significant Cause of Large Geomagnetically Induced Currents by Apatenkov, S. V., Pilipenko, V. A., Gordeev, E. I., Viljanen, A., Juusola, L., Belakhovsky, V. B., Sakharov, Ya. A., Selivanov, V. N.

“…The strongest event of geomagnetically induced currents (GIC) detected by the North‐West Russian GIC network occurred during the main phase of the magnetic…”
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Validity of a single question to assess habitual physical activity of community‐dwelling older people by Portegijs, E., Sipilä, S., Viljanen, A., Rantakokko, M., Rantanen, T.

“…The aim is to determine concurrent validity of a single self‐report habitual physical activity (PA) question against accelerometer‐based PA and mobility…”
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Space weather events in July 1982 and October 2003 and the effects of geomagnetically induced currents on Swedish technical systems by WIK, M, PIRJOLA, R, LUNDSTEDT, H, VILJANEN, A, WINTOFT, P, PULKKINEN, A

“…In this paper, we analyse in detail two famous space weather events; a railway problem on 13–14 July 1982 and a power blackout on 30 October 2003. Both…”
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Application and validation of the spherical elementary currents systems technique for deriving ionospheric equivalent currents with the North American and Greenland ground magnetometer arrays by Weygand, James M., Amm, Olaf, Viljanen, A., Angelopoulos, V., Murr, D., Engebretson, M. J., Gleisner, H., Mann, I.

“…With data from the Canadian Magnetic Observatory System, Canadian Array for Real time Investigations of Magnetic Activity, Geophysical Institute Magnetometer…”
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On‐call stress among Finnish anaesthetists by Lindfors, P. M., Nurmi, K. E., Meretoja, O. A., Luukkonen, R. A., Viljanen, A.‐M., Leino, T. J., Härmä, M I.

“…Summary We investigated on‐call stress and its consequences among anaesthetists. A questionnaire was sent to all working Finnish anaesthetists (n = 550), with…”
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GPS phase scintillation at high latitudes during the geomagnetic storm of 17–18 March 2015 by Prikryl, P., Ghoddousi‐Fard, R., Weygand, J. M., Viljanen, A., Connors, M., Danskin, D. W., Jayachandran, P. T., Jacobsen, K. S., Andalsvik, Y. L., Thomas, E. G., Ruohoniemi, J. M., Durgonics, T., Oksavik, K., Zhang, Y., Spanswick, E., Aquino, M., Sreeja, V.

“…The geomagnetic storm of 17–18 March 2015 was caused by the impacts of a coronal mass ejection and a high‐speed plasma stream from a coronal hole. The…”
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Hearing as a Predictor of Falls and Postural Balance in Older Female Twins by Viljanen, Anne, Kaprio, Jaakko, Pyykkö, Ilmari, Sorri, Martti, Pajala, Satu, Kauppinen, Markku, Koskenvuo, Markku, Rantanen, Taina

“…Background The purpose of the present study was to examine, first, whether hearing acuity predicts falls and whether the potential association is explained by…”
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Climatology of rapid geomagnetic variations at high latitudes over two solar cycles by Viljanen, A, Tanskanen, E

“…We investigate the characteristics of rapid geomagnetic variations at high latitudes based on the occurrence of large time derivatives of the horizontal…”
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From space weather toward space climate time scales: Substorm analysis from 1993 to 2008 by Tanskanen, E. I., Pulkkinen, T. I., Viljanen, A., Mursula, K., Partamies, N., Slavin, J. A.

“…Magnetic activity in the Northern Hemisphere auroral region was examined during solar cycles 22 and 23 (1993–2008). Substorms were identified from ground‐based…”
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Fear of falling and coexisting sensory difficulties as predictors of mobility decline in older women by Viljanen, Anne, Kulmala, Jenni, Rantakokko, Merja, Koskenvuo, Markku, Kaprio, Jaakko, Rantanen, Taina

“…Mobility decline, the coexistence of several sensory difficulties and fear of falling (FOF) are all common concerns in older people; however, knowledge about…”
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Magnetosheath control of solar wind‐magnetosphere coupling efficiency by Pulkkinen, T. I., Dimmock, A. P., Lakka, A., Osmane, A., Kilpua, E., Myllys, M., Tanskanen, E. I., Viljanen, A.

“…We examine the role of the magnetosheath in solar wind‐magnetosphere‐ionosphere coupling using the Time History of Events and Macroscale Interactions during…”
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Atmospheric data over a solar cycle: no connection between galactic cosmic rays and new particle formation by Kulmala, M., Riipinen, I., Nieminen, T., Hulkkonen, M., Sogacheva, L., Manninen, H. E., Paasonen, P., Petäjä, T., Dal Maso, M., Aalto, P. P., Viljanen, A., Usoskin, I., Vainio, R., Mirme, S., Mirme, A., Minikin, A., Petzold, A., Hõrrak, U., Plaß-Dülmer, C., Birmili, W., Kerminen, V.-M.

“…Aerosol particles affect the Earth's radiative balance by directly scattering and absorbing solar radiation and, indirectly, through their activation into…”
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Short telomere length is associated with impaired cognitive performance in European ancestry cohorts by Hägg, S, Zhan, Y, Karlsson, R, Gerritsen, L, Ploner, A, van der Lee, S J, Broer, L, Deelen, J, Marioni, R E, Wong, A, Lundquist, A, Zhu, G, Hansell, N K, Sillanpää, E, Fedko, I O, Amin, N A, Beekman, M, de Craen, A J M, Degerman, S, Harris, S E, Kan, K-J, Martin-Ruiz, C M, Montgomery, G W, Adolfsson, A N, Reynolds, C A, Samani, N J, Suchiman, H E D, Viljanen, A, von Zglinicki, T, Wright, M J, Hottenga, J-J, Boomsma, D I, Rantanen, T, Kaprio, J A, Nyholt, D R, Martin, N G, Nyberg, L, Adolfsson, R, Kuh, D, Starr, J M, Deary, I J, Slagboom, P E, van Duijn, C M, Codd, V, Pedersen, N L

“…The association between telomere length (TL) dynamics on cognitive performance over the life-course is not well understood. This study meta-analyses…”
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Solar Cycle Occurrence of Alfvénic Fluctuations and Related Geo‐Efficiency by Tanskanen, E. I., Snekvik, K., Slavin, J. A., Pérez‐Suárez, D., Viljanen, A., Goldstein, M. L., Käpylä, M. J., Hynönen, R., Häkkinen, L. V. T., Mursula, K.

“…We examine solar wind intervals with Alfvénic fluctuations (ALFs) in 1995–2011. The annual number, the total annual duration, and the average length of ALFs…”
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Ionospheric disturbance magnetic field continuation from the ground to the ionosphere using spherical elementary current systems by AMM, O, VILJANEN, A

“…A new technique for continuation of the ground magnetic field caused by ionospheric currents to the ionosphere in spherical geometry is presented that makes…”
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Relation between substorm characteristics and rapid temporal variations of the ground magnetic field by VILJANEN, A, TANSKANEN, E. I, PULKKINEN, A

“…Auroral substorms are one of the major causes of large geomagnetically induced currents (GIC) in technological systems. This study deals with different phases…”
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Auroral electrojets during deep solar minimum at the end of solar cycle 23 by Pulkkinen, T. I., Tanskanen, E. I., Viljanen, A., Partamies, N., Kauristie, K.

“…We investigate the auroral electrojet activity during the deep minimum at the end of solar cycle 23 (2008–2009) by comparing data from the IMAGE magnetometer…”
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Solar wind control of ionospheric equivalent currents and their time derivatives by Juusola, L., Kauristie, K., van de Kamp, M., Tanskanen, E. I., Mursula, K., Asikainen, T., Andréeová, K., Partamies, N., Vanhamäki, H., Viljanen, A.

“…A solid understanding of the solar wind control of ground magnetic field disturbances is essential for utilizing the existing long time series of ground data…”
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