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    The Scientific Foundations of Forecasting Magnetospheric Space Weather

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    The magnetosphere is the lens through which solar space weather phenomena are focused and directed towards the Earth. In particular, the non-linear interaction of the solar wind with the Earth's magnetic field leads to the formation of highly inhomogenous electrical currents in the ionosphere which can ultimately result in damage to and problems with the operation of power distribution networks. Since electric power is the fundamental cornerstone of modern life, the interruption of power is the primary pathway by which space weather has impact on human activity and technology. Consequently, in the context of space weather, it is the ability to predict geomagnetic activity that is of key importance. This is usually stated in terms of geomagnetic storms, but we argue that in fact it is the substorm phenomenon which contains the crucial physics, and therefore prediction of substorm occurrence, severity and duration, either within the context of a longer-lasting geomagnetic storm, but potentially also as an isolated event, is of critical importance. Here we review the physics of the magnetosphere in the frame of space weather forecasting, focusing on recent results, current understanding, and an assessment of probable future developments.Peer reviewe

    Właściwości przeciwbakteryjne ekstraktów i ich frakcji trzech gatunków Eryngium L.

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    Introduction: Due to increasing resistance against antibiotics and antifungal agents, crude plant extracts, fractions, and isolated pure compounds became a new interest as antimicrobial agents. Objectives: The antimicrobial activity of methanolic extracts and fractions of Eryngium planum L., E. campestre L., and E. maritimum L. was evaluated against selected bacteria, yeast and mould, and compared in tested Eryngium species and in their organs. Methods: The antimicrobial activity was studied with use of broth microdilution method. The antibacterial (Staphylococcus aureus, Pseudomonas aeruginosa) and antifungal (Candida albicans, Aspergillus niger) activity of selected extracts and fractions compared with the reference substance was expressed by Minimal Inhibitory Concentration (MIC) and Minimal Bactericidal/Fungicidal Concentration (MBC/MFC).The extract and fraction compounds were identified on the basis of TLC examination. Results: The saponin-phenolic acid fractions of E. maritimum and E. planum and a saponin fraction of E. planum showed the highest activity against S. aureus (MIC = 1–2.5 mg·ml-1). The growth of C. albicans was inhibited by methanolic extract of E. planum cell suspension culture (MIC = 7.8 mg·ml-1). Conclusion: The antimicrobial activity depends on the Eryngium species, tested biomass, and microorganism.Wstęp: Z powodu rosnącej oporności na antybiotyki i środki przeciwgrzybicze rośnie zainteresowanie ekstraktami roślinnymi, frakcjami i wyizolowanymi czystymi związkami jako środkami przeciwdrobnoustrojowymi. Cel: Badano aktywność przeciwdrobnoustrojową ekstraktów metanolowych i frakcji Eryngium planum L., E. campestre L. i E. maritimum L. w stosunku do wybranych bakterii, drożdżaka i grzyba pleśniowego oraz porównywano badane gatunki Eryngium i ich organy. Metody: Aktywność przeciwdrobnoustrojową badano z zastosowaniem metody seryjnych rozcieńczeń w bulionie. Aktywność przeciwbakteryjna (Staphylococcus aureus, Pseudomonas aeruginosa) i przeciwgrzybicza (Candida albicans, Aspergillus niger) wybranych ekstraktów i frakcji, w porównaniu z substancją referencyjną, wyrażona została za pomocą minimalnego stężenia hamującego (MIC) i minimalnego stężenia bakterio- lub grzybobójczego (MBC/MFC). Wyniki: Frakcje saponinowo-fenolokwasowe E. maritimum i E. planum oraz frakcja saponinowa E. planum wykazały najwyższą aktywność wobec S. aureus (MIC = 1–2,5 mg∙ml -1). Wzrost C. albicans był hamowany przez metanolowy ekstrakt zawiesiny komórkowej E. planum (MIC = 7,8 mg∙ml -1). Wnioski: Aktywność przeciwdrobnoustrojowa zależy od gatunku Eryngium, testowanej biomasy i mikroorganizmu

    The Scientific Foundations of Forecasting Magnetospheric Space Weather

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