Fast cosmic microwave background power spectrum estimation of temperature and polarization with Gabor transforms     

Frode K. Hansen  Krzysztof M. Górski 《Monthly notices of the Royal Astronomical Society》2003,343(2):559-584

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Pleurozium schreberi as bioindicator of mercury pollution in heavily industrialized region     

Aleksandra Samecka-Cymerman  Grzegorz Kosior  Krzysztof Kolon  Bronisław Wojtuń  Krzysztof Zawadzki  Andrzej Rudecki  Alexander J. Kempers 《Journal of Atmospheric Chemistry》2013,70(2):105-114

This research is continuation of the investigation of metal accumulation in native and transplanted moss Pleurozium schreberi in the most industrialized and affected region in Poland (Upper Silesia). We tested the hypotheses that in Upper Silesia transplants of P. schreberi may be used in a 90 days bioindication experiment in case native specimens are absent; a 90 days exposure of transplanted P. schreberi was long enough for evaluation of Hg pollution of the environment. An assay was carried out with native mosses at 27 polluted sites and mosses from an uncontaminated control site transplanted to the same 27 polluted sites. P. schreberi collected from the same sites as classified for more and less polluted basing on Pb and Zn concentrations show quite different pattern of pollution with mercury; The accumulation of Hg by the transplants increased much faster in the first 45 days of the experiment (accumulation factor 1.5–6.7; mean 3.4?±?0.5) in comparison with the second period from day 45 to 90 (accumulation factor 1.0–1.6; mean 1.2?±?0.1). The 90 days exposure of transplanted P. schreberi was long enough for evaluation of Hg pollution of the environment. Transplants of P. schreberi may be used in a 90 days bioindication experiment in case native specimens are absent.  相似文献   

Gabor transforms on the sphere with applications to CMB power spectrum estimation     

Frode K. Hansen  Krzysztof M. Górski  Eric Hivon 《Monthly notices of the Royal Astronomical Society》2002,336(4):1304-1328

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Magnetic Fields in Cluster and Interacting Galaxies     

Krzysztof T. Chyży  Marek Urbanik  Marian Soida  Rainer Beck 《Astrophysics and Space Science》2002,281(1-2):409-410

Our VLA and Effelsberg radio polarization studies of the interacting and cluster galaxies (NGC 3627, NGC 4038/39, NGC 4254) show that magnetic fields could help us in understanding galaxy peculiar gas motions and cluster environmental effects. This revised version was published online in September 2006 with corrections to the Cover Date.  相似文献   

Thermodynamic properties and phase stability of wadsleyite II     

Kamil Tokár  Paweł T. Jochym  Przemysław Piekarz  Jan Łażewski  Małgorzata Sternik  Krzysztof Parlinski 《Physics and Chemistry of Minerals》2013,40(3):251-257

The thermodynamical stability of a newly observed wadsleyite II phase in the Mg₂SiO₄ system is studied by the density functional theory. The wadsleyite II equation of state has been derived. The phase boundaries of Mg₂SiO₄ polymorphs: wadsleyite, wadsleyite II and ringwoodite are studied using the quasi-harmonic approximation at high external pressures. Clapeyron slopes determined for wadsleyite II–ringwoodite and wadsleyite–wadsleyite II boundaries are 0.0047 and 0.0058 GPa/K, respectively. It is shown that the wadsleyite II phase is not thermodynamically preferred in the pure Mg₂SiO₄ system and will probably not occur between wadsleyite and ringwoodite phases.  相似文献   

Paleomagnetism and magnetic mineralogy of metabasites and granulites from Orlica-Śnieżnik Dome (Central Sudetes)     

Magdalena Kądziałko-Hofmokl  Jacek Szczepański  Tomasz Werner  Maria Jeleńska  Krzysztof Nejbert 《Acta Geophysica》2013,61(3):535-568

The results of palaeomagnetic, rock magnetic, and microscopic study of Early Paleozoic metabasites and granulites from the Orlica?nie?nik Dome (OSD, Sudetes) have been combined with geochronological data. In the eastern part of the OSD (?nie?nik Massif, SM) ferrimagnetic pyrrhotite is prevalent, accompanied by various amounts of Fe-oxides. In the western part of the OSD (Orlica-Bystrzyca Massif, OBM) Fe-oxides dominate. All magnetic minerals originated during hydrothermal and weathering processes. The palaeomagnetic study revealed the presence of three secondary components of natural remanence: Late Carboniferous, Late Permian, and Mesozoic. Two Paleozoic components are related to volcanic activity in the Sudetes. They are carried by pyrrhotite and Fe-oxides and were isolated only in SM rocks. The Mesozoic component was determined in both parts of the OSD and is carried by Fe-oxides. It covers a time span, from ～160 to ～40 Ma, corresponding to a long period of alteration.  相似文献   

Late Holocene changes in cyanobacterial community structure in maritime Antarctic lakes     

Rafael Fernandez-Carazo  Elie Verleyen  Dominic A. Hodgson  Stephen J. Roberts  Krzysztof Waleron  Wim Vyverman  Annick Wilmotte 《Journal of Paleolimnology》2013,50(1):15-31

Despite the dominance of cyanobacteria in polar freshwater aquatic ecosystems, little is known about their past biodiversity and response to climate and environmental changes. We explored the use of light microscopy of microfossils, high performance liquid chromatography of the fossil pigment composition and denaturing gradient gel electrophoresis of fossil 16S rRNA genes to study past and present-day differences in cyanobacterial community structure in response to climate changes in two adjacent maritime Antarctic lakes with contrasting depths (4 and 26 m) and light climates. Light microscopy was of limited use because of degradation of cell structures. Fossil cyanobacterial pigment concentrations were below the detection limits of our method in several sediment samples in the deep lake, but abundant and diverse in the sediment core from the shallow pond, probably as a consequence of increased light availability and/or a more diverse and abundant benthic cyanobacterial flora. Total carotenoid and chlorophyll concentrations were highest in both lakes between ca. 2,950 and 1,800 cal yr BP, which coincides with the late Holocene climate optimum recognised elsewhere in maritime Antarctica. Cyanobacterial molecular diversity was higher in the top few centimeters of the sediments in both lakes. In deeper sediments, the taxonomic turnover of cyanobacteria appeared to be relatively small in response to past climate anomalies in both lakes, underscoring the broad tolerance of cyanobacteria to environmental variability. This, however, may in part be explained by the low taxonomic resolution obtained with the relatively conserved 16S rRNA gene and/or the preferential preservation of particular taxa. Our results highlight the potential of fossil DNA in lake sediments to study colonization and succession dynamics of lacustrine cyanobacteria and warrant further investigation of the factors that affect preservation of cyanobacterial DNA.  相似文献   

Mesozoic marine reptiles from Spitsbergen and their ecosystems     

Lene L. Delsett  Patrick S. Druckenmiller   yvind Hammer  Krzysztof Hryniewicz  Espen M. Knutsen  Maayke J. Koevoets  Hans A. Nakrem  Aubrey J. Roberts  Jrn H. Hurum 《Geology Today》2019,35(1):20-25

In the Mesozoic seas, the apex predators were reptiles. From the Arctic archipelago of Svalbard, the Spitsbergen Mesozoic Research Group has excavated numerous well preserved marine reptile skeletons in order to understand the biology of these animals and the environment they lived in. The work of eleven field seasons has made this one of the largest and most productive palaeontological research projects in the high Arctic world‐wide. The initial eight seasons focused on one of the richest occurrences of Late Jurassic—earliest Cretaceous (c. 150–139 Ma) marine reptiles in the world, and nearly sixty specimens have been collected, together with a diverse assemblage of invertebrates, some of which are associated with methane seeps. The last three seasons were spent investigating events further back in time, as Spitsbergen preserves the remains from some of the first marine reptile radiations in the wake of the most devastating extinction in the history of the Earth, at the Permian–Triassic boundary (c. 252 Ma).  相似文献   

A new magnetic index based on the external part of vertical geomagnetic variations     

Tomasz Ernst  Jerzy Jankowski  Krzysztof Nowożynski 《Acta Geophysica》2010,58(6):963-972

Variations of geomagnetic components X, Y, and Z recorded in 19 Intermagnet European observatories in 2004 were analysed. The original data from all observatories were preliminarily processed. In the first step, periods longer than three hours were filtered out. In the second step, variations of vertical geomagnetic component Z were separated into external and internal parts. We introduced a non-dimensional index η defined as the square root of a ratio of the energy of the external part of the vertical component to that of the horizontal components. Maps of the surface distribution of a new magnetic index η for the area of Europe at selected time periods were created, and their time changes are presented. The time changes of η for selected observatories are also shown. Moreover, we discuss a very interesting phenomenon we discovered, that has never been described in geophysical literature. Namely, in the recordings of all the observatories we noticed the presence of very regular variations, observed almost exclusively in the vertical component Z, which is quite unusual. These regular variations occur in the form of sinusoidal “wave packets”. The amplitudes of these variations do not depend on the geomagnetic latitude and appear in the records of all the observatories we analyzed. They occur in quiet days, which suggests that their source is in the ionosphere.  相似文献   

Usefulness of AFORS—autonomous fibre-optic rotational seismograph for investigation of rotational phenomena     

Leszek R. Jaroszewicz  Zbigniew Krajewski  Krzysztof P. Teisseyre 《Journal of Seismology》2012,16(4):573-586

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