A new method for spectral analysis of non-stationary signals from impact tests

To obtain the spectrum of impulse response from impact test, the paper proposes an approach based on envelope of cross-correlation function. This is achieved by correlating the impulse response and reference single-harmonic signals. An envelope of cross-correlation makes it possible to detect and identify the harmonics of impulse response. The presented method gives a possibility to point the frequency value of the harmonic component of an impulse response signal independently of the commonly used fast Fourier transform. Its main advantage over the fast Fourier transform is that the spectral resolution does not depend on duration of the impulse response

Symplectic geometry of entanglement

We present a description of entanglement in composite quantum systems in terms of symplectic geometry. We provide a symplectic characterization of sets of equally entangled states as orbits of group actions in the space of states. In particular, using Kostant-Sternberg theorem, we show that separable states form a unique Kaehler orbit, whereas orbits of entanglement states are characterized by different degrees of degeneracy of the canonical symplectic form on the complex projective space. The degree of degeneracy may be thus used as a new geometric measure of entanglement and we show how to calculate it for various multiparticle systems providing also simple criteria of separability. The presented method is general and can be applied also under different additional symmetry conditions stemming, eg. from the indistinguishability of particles.Comment: LaTex, 31 pages, typos correcte

Middle Pleistocene fauna and palaeoenvironment in the south of Eastern Europe: A case study of the Medzhybizh 1 locality (MIS 11, Ukraine)

The Middle Pleistocene was a period of dynamic changes in Europe. During MIS 11, a number of modern mammal taxa appeared and environmental conditions remained warm and favourable for a relatively long time. The Medzhybizh 1 locality of Ukraine dated to this very period comprises alluvial deposits with rich animal remains, which allow not only to reconstruct the fauna composition, but also to highlight the environmental conditions that dominated at this locality. A revision of the fauna of Medzhybizh 1 locality based on remains of all vertebrate groups revealed a taxonomically diverse fish community (16 species of 11 genera) dominated by cyprinids common for lacustrine or riverine assemblages. Amphibians are represented by 11 species, while the number of reptile and bird remains are less significant. Mammals are the most represented group at the locality, including small mammals (30 species), carnivorans (2 species), and ungulates (5 taxa), the latter dominated by C. elaphus. The taxonomic composition of terrestrial groups indicates temperate climate with boreal-type forests and meadows similar to cold steppe, as well as low wet areas and riparian habitats inhabited by amphibians, reptiles, insectivores, beavers, and various voles. The fish assemblage indicates a partially overgrown but well-aerated water body (lake or slow-flowing river) with sandy-silty bottom. Lithic artefacts found at the Medzhybizh 1 locality contribute to a better understanding of relationships between ancient hominins and faunas during the Middle Pleistocene of Eastern Europe.Archaeological field works at Medzhybizh were supported by the NASU state research projects 0105U001383 (2005–2009), 0109U008921 (2010–2014) and partly funded by the State Fund of Fundamental Research of Ukraine grant 0118U001457 (F77/50–2018). This research was also supported by the grant 0201/2048/18 ‘Life and death of extinct rhino (Stephanorhinus sp.) from Western Poland: a multi-proxy palaeoenvironmental approach’ financed from the funds of the National Science Centre, Poland. JvdM received support from the Spanish Ministerio de Ciencia, Inovación y Universidades (current grant numbers PGC2018-093925-B-C31 and PGC2018-095489-B-I00).Peer reviewe

Browsers, grazers or mix-feeders? Study of the diet of extinct Pleistocene Eurasian forest rhinoceros Stephanorhinus kirchbergensis (J¨ager, 1839) and woolly rhinoceros Coelodonta antiquitatis (Blumenbach, 1799)

The wooly rhinoceros (Coelodonta antiquitatis) and forest rhinoceros (Stephanorhinus kirchbergensis) were prominent representatives of the Middle and Late Pleistocene glacial and interglacial faunas of Eurasia. Their diet has traditionally been inferred on functional morphology of the dentition and skull. In rare cases, food remains are preserved in the fossas of the teeth or as gut content. New approaches to infer diet include the study of isotopes and mesowear. Here we apply all four methods to infer the diet of these emblematic rhinoceros’ species and compare the food actually taken with the food available, as indicated by independent botanical data from the localities where the rhinoceros’ fossils were found: Gorz´ow Wielkopolski (Eemian) and Starunia (Middle Vistulian) as well as analysis of literature data. We also made inferences on the season of death of these individuals. Our results indicate that the woolly rhino in both Europe and Asia (Siberia) was mainly a grazer, although at different times of the year and depending on the region its diet was also supplemented by leaves of shrubs and trees. According to the results of isotope studies, there were important individual variations. The data show a clear seasonal variation in the isotope composition of this rhino’s diet. In contrast, Stephanorhinus kirchbergensis was a browser, though its diet included low-growing vegetation. Its habitat consisted of various types of forests, from riparian to deciduous and mixed forests, and open areas. The diet of this species consisted of selected items of vegetation, also including plants growing near both flowing and standing waters. The food remains from the fossae of the teeth indicated flexible browsing, confirming the previous interpretations based on functional morphology and stable isotopes. Long-term data from mesowear and microwear across a wider range of S. kirchbergensis fossils indicate a more mixed diet with a browsing component. The different diets of both of rhinoceros reflect not only the different habitats, but also climate changes that occurred during the Late Pleistocene

Diversity of muskox Ovibos moschatus (Zimmerman, 1780) (Bovidae, Mammalia) in time and space based on cranial morphometry

Muskox Ovibos moschatus is a Pleistocene relic, which has survived only in North America and Greenland. During the Pleistocene, it was widely distributed in Eurasia and North America. To evaluate its morphological variability through time and space, we conducted an extensive morphometric study of 217 Praeovibos and Ovibos skull remains. The analyses showed that the skulls grew progressively wider from Praeovibos sp. to the Pleistocene O. moschatus, while from the Pleistocene to the recent O. moschatus, the facial regions of the skull turned narrower and shorter. We also noticed significant geographic differences between the various Pleistocene Ovibos crania. Siberian skulls were usually larger than those from Western and Central Europe. Eastern Europeanmuskoxen also exceeded in size those from the other regions of Europe. The large size of Late Pleistocene muskoxen from regions located in more continental climatic regimes was probably associated with the presence of more suitable food resources in steppe-tundra settings. Consistently, radiocarbon-dated records of this species are more numerous in colder periods, when the steppe-tundra was widely spread, and less abundant in warmer periods

A skeleton of peat-trapped forest rhinoceros Stephanorhinus kirchbergensis (Jäger, 1839) from Gorzów Wielkopolski, Northwestern Poland: a record of life and death of the Eemian large mammals

We present a description of an almost complete skeleton of the forest rhino (Stephanorhinus kirchbergensis) found near Gorzów Wielkopolski (Northwest Poland) in its geological and palaeoenvironmental context. While finds of bones and teeth are common, the importance of this find resides in, that it is the most complete specimen of this species, almost perfectly preserved in a well-studied and dated stratigraphic and sedimentological context, along with other fossil fauna and flora. The OSL dates of glaciofluvial sediments sandwiching skeleton-bearing horizons indicate a Middle Eemian age of the Pleistocene paleolake land. This warm climate is also indicated by the results of sedimentological, geochemical, paleobotanical, and isotopic analyses. The rhino skeleton was deposited in a shallow area near the lake’s littoral zone. Bite marks of a large predator (cave hyena) were recognized on the rhino’s pelvis, which, due to their location, were probably created post-mortem. With an estimated height of 1.82 m at the withers, this was a large adult Stephanorhinus kirchbergensis. The results of osteometric analyses indicate that we are dealing with one of the largest known individuals of this species. Although it suffered from a pathologically deformed spine, the individual died at a relatively old age.Peer reviewe

Cross-Correlation-Based Method vs. Classical Fft for Spectral Analysis of Impulse Response

The paper presents comparison of results of impulse response spectral analysis that has been obtained using a method based on cross-correlation with results obtained using classical FFT. The presented non-Fourier method is achieved by correlating the analyzed signal and reference single-harmonic signals and using Hilbert transform to obtain an envelope of cross-correlation. The envelope of crosscorrelation makes it possible to calculate appropriate indicator and make its plot in frequency domain as a spectrum. The spectrum obtained this way has its advantage over the FFT that the spectral resolution does not depend on duration of signal. At the same time, the spectral resolution can be much greater than spectral resolution resultant from FFT. Obtained results show that presented non-Fourier method gives frequency readout more accurate in comparison to FFT when the impulse response is a short-time signal e.g. few dozen of miliseconds lasting

Rapid and Sensitive Analysis of Hormones and Other Emerging Contaminants in Groundwater Using Ultrasound-Assisted Emulsification Microextraction with Solidification of Floating Organic Droplet Followed by GC-MS Detection

Ultrasound-assisted emulsification microextraction with solidification of floating organic droplet (USAEME-SFOD) has been applied to isolate hormones and other emerging contaminants from groundwater samples. Simultaneously with the extraction process, derivatization in the matrix was carried out using acetic anhydride. Quantification of studied organic pollutants was done through gas chromatography mass spectrometry (GC-MS). Hormones included β-estradiol (E2), estrone (E1), and diethylstilbestrol (DES). Other compounds belonged to groups of pharmaceuticals (diclofenac (DIC)), antiseptics (triclosan (TRC)), preservatives (propylparaben (PP) and butylparaben (BP)), sunscreen agents (benzophenone (BPH), and 3-(4-methylbenzylidene)camphor (3MBC)), repellents (N,N-diethyltoluamide (DEET)), industrial chemicals (bisphenol A (BPA), 4-t-octylphenol (4OP), 4-n-nonylphenol (4NP)). A non-toxic and inexpensive 1-undecanol was successfully used as the extraction solvent. Volume of extractant and derivatization agent, ionic strength, and time of extraction were optimized. Very low limits of detection (LoD) ranging from 0.01 to 5.9 ng/L were obtained. Recoveries ranged from 90% to 123%, with relative standard deviation being lower than 17%. The developed procedure was used to determine target compounds in groundwater collected at municipal waste landfills as well as in groundwater from wells distant from sources of pollution