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Tytuł:
A study of stable isotope composition of chosen foodstuffs from the Polish market
Autorzy:
Malec-Czechowska, K.
Wierzchnicki, R.
Powiązania:
https://bibliotekanauki.pl/articles/148152.pdf
Data publikacji:
2013
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
stable isotope
honey
meat
hen eggs
food authenticity
Opis:
In the present work the carbon and nitrogen isotopic composition of food products bought in the retail trade in Warsaw is demonstrated. The research was carried out using meat (pork, chicken), hen eggs and honey. These products originated from the conventional and ecological farms. The values of the isotopic ratios are expressed as δ notation and correspond to the international standards (V-PDB for δ13C, and air for δ15N) according to the following general formula: δ(‰) = [(R sample / R standard) – 1] × 1000, where R represents the ratio between the less abundant and more abundant isotopes, in particular 13C/12C and 15N/14N. The results received in our laboratory, were compared with results presented in the literature for similar products. The results of the study show that the N and C stable isotope ratios in the tested products can be applied to verify their authenticity.
Źródło:
Nukleonika; 2013, 58, 2; 323-327
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Carbon and oxygen isotope variability among foraminifera and ostracod carbonated shells
Autorzy:
Fourel, François
Martineau, François
Emoke Tóth, Emoke
Görög, Agnes
Escarguel, Gilles
Lécuyer, Christophe
Powiązania:
https://bibliotekanauki.pl/articles/763395.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej
Tematy:
stable isotope
foraminifera
ostracod
heterogeneity
single shell analysis
Opis:
This study investigates the effect of biological and environmental inter-individual variability on the meaning of d18O and d13C values acquired on small carbonated shells. First we present data obtained with a MultiPrep automated carbonate system on small sample sizes of a homogeneous carbonate material: Carrara marble. This demonstrates the capacities of the analytical system to reliably run small amounts of carbonates even down to 10 mg. Then we present two data sets obtained on real fossil samples of various size (sensu number of individual organisms) calibrated against the NBS19 carbonate standard. Both datasets evidence a clear trend of between-biological sample standard deviation increase for both d18O and d13C measurements when the number of pooled specimens per sample decreases. According to the results obtained from a systematic study of a geologically homogeneous sample of coeval fossil Elphidium foraminifera, we estimate that there is 95% of chances to reach between-biological sample standard deviation values higher than 1.02‰ (d18O) and 1.45‰ d13C) based on single-cell measurements. Such values are one order of magnitude higher than the instrumental standard deviations associated with these stable isotope ratios. Conversely, a minimum of 35 (d18O) and 44 (d13C) pooled specimens of Elphidium appears necessary to reach a between-sample standard deviation £ 0.25‰ with a probability of 95%. Such biological intrinsic and irreducible variability between coeval individuals, and thus samples, clearly questions the interest for single-cell analyses, more precisely, for coastal marine species, such as Elphidium, subject to many environmental changes during their life-time. Indeed, strong variations in salinity or temperature, as well as biogenic fractionation, could influence the isotopic composition of an individual specimen. Results might be less problematic for an average community including several tests. This paper underlines uncertainties linked to specific environments in which selected organisms live, especially for paleoceanographic or paleoclimatic reconstruction purposes where secular oxygen and carbon isotope variations typically range from 0.5 to 1.5‰.
Źródło:
Annales Universitatis Mariae Curie-Skłodowska, sectio AAA – Physica; 2015, 70
0137-6861
Pojawia się w:
Annales Universitatis Mariae Curie-Skłodowska, sectio AAA – Physica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Unraveling cementation environment and patterns of Holocene beachrocks in the Arabian Gulf and the Gulf of Aqaba : stable isotope approach
Autorzy:
Koeshidayatullah, A.
Al-Ramadan, K.
Powiązania:
https://bibliotekanauki.pl/articles/2059746.pdf
Data publikacji:
2014
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
cementation
beachrocks
stable isotope
Arabian Gulf
Gulf of Aqaba
Opis:
This paper analyses Holocene beachrocks from the Arabian Gulf and the Gulf of Aqaba to explain the mechanisms that influence the cementation process in these areas. Holocene beachrocks in the Gulf of Aqaba are composed of predominantly terrigenous material derived from erosion of adjacent uplifted Precambrian basement, while the beachrocks in the Arabian Gulf are composed mainly of marine bioclasts and wind-blown siliciclastic sands. The cements of beachrocks in both areas show three textural varieties: (1) isopachous phreatic acicular aragonite; (2) a micritic envelope of high-Mg calcite (HMC); (3) meniscus and gravitational vadose HMC. Radiocarbon dating of beachrock samples from the Arabian Gulf yielded ages from ca. 2300 to 660 yr cal BP whereas samples from the Gulf of Aqaba range in age between 5500 and 2800 yr cal BP. Oxygen isotope values range from 2.6 to 4.4‰ respectively for the Arabian Gulf whereas the Gulf of Aqaba values range from 1.2 to 1.5‰. Carbon isotope values range from 3.2 to 5.9‰ for the Arabian Gulf whereas those from the Gulf of Aqaba range from 3.8 to 4.6‰. The values of δ18OVPDB and δ13CVPDB in the beachrocks of both areas suggest a marine origin. The beachrocks of the Arabian Gulf were precipitated under high evaporation conditions, while beachrocks from the Gulf of Aqaba were precipitated in normal shallow-marine conditions. The mineralogy and textural habits suggest that cementation of these beachrocks started within the shallow-marine phreatic zone.
Źródło:
Geological Quarterly; 2014, 58, 2; 207--216
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Antibiotic therapy and fat digestion and absorption in cystic fibrosis
Autorzy:
Lisowska, Aleksandra
Pogorzelski, Andrzej
Oracz, Grzegorz
Skorupa, Wojciech
Cofta, Szczepan
Szydłowski, Jarosław
Socha, Jerzy
Walkowiak, Jarosław
Powiązania:
https://bibliotekanauki.pl/articles/1039883.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
stable isotope breath test
malabsorption
antibiotic therapy
cystic fibrosis
Opis:
Antibiotic therapy in the cystic fibrosis (CF) mouse model has been shown to result in reduced bacterial load of the intestine and significant body mass gain. The effect was suggested to be linked to the improvement of intestinal digestion and absorption. Therefore, we aimed to assess the influence of routinely applied antibiotic therapy in CF patients on fat assimilation. Twenty-four CF patients aged 6 to 30 years entered the study. Inclusion criteria comprised confirmed exocrine pancreatic insufficiency and bronchopulmonary exacerbation demanding antibiotic therapy. Exclusion criteria comprised: antibiotic therapy six weeks prior to the test, liver cirrhosis, diabetes mellitus, oxygen dependency, the use of systemic corticosteroids. In all enrolled CF subjects, 13C-labelled mixed triglyceride breath test (13C MTG-BT) was performed to assess lipid digestion and absorption, before and after antibiotic therapy. Sixteen subjects were treated intravenously with ceftazidime and amikacin, eight patients orally with ciprofloxacin. Cumulative percentage dose recovery (CPDR) was considered to reflect digestion and absorption of lipids. The values are expressed as means (medians). The values of CPDR before and after antibiotic therapy did not differ in the whole studied group [4.6(3.3) % vs. 5.7(5.3) %, p = 0.100] as well as in the subgroup receiving them intravenously [4.6(3.2) % vs. 5.7(5.3) %, p = 0.327] or in that with oral drug administration [4.6(3.4) % vs. 5.7(5.4) %, p = 0.167]. In conclusion, antibiotic therapy applied routinely in the course of pulmonary exacerbation in CF patients does not seem to result in an improvement of fat digestion and absorption.
Źródło:
Acta Biochimica Polonica; 2011, 58, 3; 345-347
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Black "marble" in the Polish architecture - characteristics and possibility of its provenance determination: the case of the Dębnik limestone
Autorzy:
Marszałek, M.
Powiązania:
https://bibliotekanauki.pl/articles/184492.pdf
Data publikacji:
2014
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
black limestone
provenance
petrography
stable isotope geochemistry
deterioration
Polska
Belgium
Opis:
Black limestone, also known as black "marble", was widely used in the Polish small-scale architecture and art of the 17th and 18th centuries. Besides the Devonian limestone from Dębnik near Krakow, also popular were the Netherlandish (Wallonian), Devonian to Carboniferous limestones from the Meuse River and Schelde River valleys. This paper deals with the possibility of identifying the rocks imported to Poland. Macroscopic similarities between the Netherlandish rocks and some Dębnik limestones have been highlighted for the oldest Carmelite quarry in Dębnik, exploiting the best stones. The analyses include: optical microscopy, scanning electron microscopy with EDS, X-ray diffraction, X-ray fluorescence and isotope ratio mass spectrometry (13 C and 18 O stable isotopes). Carboniferous limestones from Netherlands can be identified within and distinguished from the Dębnik limestone in the macroscopic observations. Differences, depending on the varieties, are associated primarily with the presence of white calcite fragments of fossils, calcite veins intersecting the rock in all directions or hardness of the limestones. Deeply black Devonian limestones from Wallonia and Dębnik without macrofossils and calcite veins differ in microscopic observations considering their texture, type of microfossils and inventory of non-carbonate components. The characteristic graying and whitening of the black limestones has also been discussed as a possible feature of rock provenance.
Źródło:
Geology, Geophysics and Environment; 2014, 40, 2; 189-205
2299-8004
2353-0790
Pojawia się w:
Geology, Geophysics and Environment
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Isotopic mass balance of metamorphic fluids in the Gogołów–Jordanów serpentinite massif, Lower Silesia, SW Poland
Autorzy:
Mydłowski, A.
Powiązania:
https://bibliotekanauki.pl/articles/191462.pdf
Data publikacji:
2009
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
serpentinization
stable isotope
tectonics
numerical modelling
Gogołów-Joradanów Massif
SW Poland
Opis:
This work aims at estimation of the amount of metamorphic fluids which led to the present-day variability of isotopic compositions, ?D and ?18O, in serpentinites from the Gogołów–Jordanów Massif. This goal was achieved by means of a numerical model reproducing selected features of geological environment and a computer application supporting this model. The Gogołów–Jordanów Massif consists of peridotites transformed to a different degree into serpentinites and subject to brittle deformation that produced a complex fracture system. The potential tectonic control on the pattern of the fluid migration paths was investigated using palaeostress analysis based on slickenside measurements. Isotopic analyses were carried out for hydrogen and oxygen from serpentine, oxygen from magnetite, and hydrogen and oxygen from carbonates. The variability of ?D and ?18O in the serpentinites along the modelled migration paths demonstrates that serpentinization of peridotites was caused by fluids derived from at least three sources revealing different isotopic characteristics. Fluids produced during the magmatic-hydrothermal stage played a major role in serpetinization, since they represent approximately 95% of all fluids interacting with the rock. In contrast, oceanic water represents only 1% of fluids involved in serpenti- nization. The calculated mean amount of fluid required for serpentinization of 1 m3 of peridotite is equal to 98 × 104 kg.
Źródło:
Annales Societatis Geologorum Poloniae; 2009, 79, No 2; 147-158
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Origin of sulfates in the post-mining lakes in the eastern part of Muskau Arch (Polish-German borderland)
Autorzy:
Labus, K. M.
Skoczyńska-Gajda, S.
Powiązania:
https://bibliotekanauki.pl/articles/2060557.pdf
Data publikacji:
2013
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
acid mine drainage
post-mining lakes
stable isotope analyis
Muskau Arch
Opis:
Exploitation of lignites, carried out within glaciotectonic structures of Muskau Arch, led to formation of numerous post-minng lakes impacted by Acid Mine Drainage (AMD). . The isotopic analyses decribed in this paper allowed for identification of sources of the dissolved sulphates in the waters of two representative lakes. One of the sources of sulfur isotopes could be oxidation of sulphides (supplied in debris sliding from the slopes of waste dumps, which are surrounding the lakes) in the water column. The fraction of oxygen from water in forming the sulphates vary from about 5% to 25% in the first lake, while in the second it falls within the range 25%-85%. The research confirmed that the main source of sulfates in the lakes is the oxidation of pyrite.
Źródło:
Geological Quarterly; 2013, 57, 3; 561--566
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessment of Agricultural Use of the Bottom Sediments from Eutrophic Rzeszów Reservoir
Ocena możliwości rolniczego wykorzystania osadów dennych z eutroficznego zbiornika zaporowego Rzeszów
Autorzy:
Bartoszek, L.
Koszelnik, P.
Gruca-Rokosz, R
Powiązania:
https://bibliotekanauki.pl/articles/1818154.pdf
Data publikacji:
2015
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
zbiornik zaporowy
osady denne
stabilne izotopy
reservoirs
bottom sediment
stable isotope
Opis:
Zbiornik zaporowy Rzeszów na rzece Wisłok w południowo-wschodniej Polsce, został zbudowany w 1973 roku. W trakcie jego eksploatacji, niektóre strefy zbiornika zostały zamulone i zalądowione, przez co jego powierzchnia i głębokość istotnie się zmniejszyły. Pomimo kilkukrotnych rekultywacji, zbiornik jest nadal silnie zamulony i jego funkcje użytkowe są mocno ograniczone. Celem pracy jest analiza zanieczyszczeń i możliwość wykorzystania rolniczego urobku wydobytego ze zbiornika. W pracy dokonano analizy ilościowej zarówno substancji potencjalnie toksycznych jak i biogennych w próbkach osadów pobranych w ciągu ostatnich pięciu lat ze stanowisk zlokalizowanych wzdłuż osi zbiornika. Ponadto, zostało oszacowane pochodzenie materii organicznej zawartej w tych osadach. W tym celu wykorzystano analizy zawartości stabilnych izotopów N i C jak również stosunków elementarnych tych pierwiastków. Krzemionka była dominującym składnikiem osadu (około 67% suchej masy osadu), zaś materia organiczna (OM) stanowiła około 10% s.m.o. Stężenia związków biogennych: OWO, azotu ogólnego i fosforu ogólnego wynosiły średnio odpowiednio 2,31%, 0,21% i 0,031% s.m.o. Pochodzenie osadów dennych zbiornika Rzeszów jest mieszane. Niespodziewanie wysoki udział materii autochtonicznej może być wynikiem intensywnej eutrofizacji wód zbiornika. Zawartości WWA były stosunkowo niskie. Najwyższe zauważone stężenie wynosiło 0,164 ppm w przypadku benzo(k)fluorantenu. Zawartość benzo(a)pirenu była niższa od 0,14 ppm. Poziomy stężeń wybranych kongenerów PCB mieściły się w przedziale od 0,0006 do 0,003 ppm i były poniżej wartości normatywnych. Badane osady były umiarkowanie zanieczyszczone metalami ciężkimi (Cu, Cd, Cr, Zn, Ni, Pb). Średnie stężenia wszystkich metali przekraczały sporadycznie tło geochemiczne i poziom TEC, ale wartość PEC nie została przekroczona w żadnej z analizowanych próbek. Charakter badanych osadów wskazuje, że nie są one odpowiednie do stosowania w rolnictwie ze względu na zanieczyszczenie i brak żyzności. Jednak mogą one być wykorzystywane do rekultywacji gruntów nierolniczych. Istnieją metody umożliwiające usunięcie z wydobytego materiału z tych zanieczyszczeń, głównie metali ciężkich, ale z uwagi na znaczne ilości urobku proces może okazać się nieopłacalny.
Źródło:
Rocznik Ochrona Środowiska; 2015, Tom 17, cz. 1; 396-409
1506-218X
Pojawia się w:
Rocznik Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stanowisko mamuta – Mammuthus primigenius (Blumenbach, 1799) w górnym plejstocenie Kopalni Węgla Brunatnego Bełchatów
Mammuthus primigenius (Blumenbach, 1799) fromUpper Pleistocene deposits of the Be³chatów Coal Mine
Autorzy:
Błażejowski, B.
Jakubowski, G.
Gieszcz, P.
Kowalski, R.
Hołda-Michalska, A.
Powiązania:
https://bibliotekanauki.pl/articles/2075107.pdf
Data publikacji:
2014
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
mamut włochaty
izotopy stabilne w zębach
Bełchatów
woolly mammoth
stable isotope composition of teeth
Opis:
The fossil remains of juvenile woolly mammoth (Mammuthus primigenius) from Pleistocene deposits of the Be³chatów coal mine are described. Precise measurements of the excavated bones allowed for approximate reconstruction of the specimen, which turned out to be in the estimated age of 10 years. Serial samples for isotope analysis of carbon and oxygen were taken from a tooth, and the isotope record has revealed a probable change of diet due to switching from milk-based to plant-based food.
Źródło:
Przegląd Geologiczny; 2014, 62, 11; 755--760
0033-2151
Pojawia się w:
Przegląd Geologiczny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Trophic connectivity between intertidal and offshore food webs in Mirs Bay, China
Autorzy:
Ning, J.
Du, F.
Wang, X.
Wang, L.
Li, Y.
Powiązania:
https://bibliotekanauki.pl/articles/47613.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
intertidal zonation
offshore zone
food web
different habitat
trophic interaction
stable isotope
carbon isotope composition
Mirs Bay
China
Źródło:
Oceanologia; 2019, 61, 2
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Tracing the signature of various frontal systems in stable isotopes (oxygen and carbon) of the planktonic foraminiferal species Globigerina bulloides in the Southern Ocean (Indian Sector)
Autorzy:
Khare, N.
Chaturvedi, S.K.
Powiązania:
https://bibliotekanauki.pl/articles/48922.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
Foraminifera
Globigerina bulloides
stable isotope
frontal system
oxygen
carbon
foraminiferal species
water mass
Southern Ocean
Opis:
Twenty-five surficial sediment samples, collected on board ORV Sagar Kanya during her 199th and 200th cruises along a north-south transect between latitudes 9.69◦N and 55.01◦S, and longitudes 80◦E and 40◦ E were studied for isotopic variations (values of δ18O and δ13C) of the indicator planktonic species Globigerina bulloides. The results indicate that from latitudes 9.69◦N to 15◦ S both these isotopes (δ18O and δ13C) fluctuated significantly. Between latitudes from around 15◦S to 30–35◦S δ18O values steadily increased, whereas δ13C showed a decreasing trend. However, to the south of latitudes 30–35◦S, both isotope values showed a similar response with a gradual increase up to latitude 50◦S, beyond which δ18O continued to increase while δ13C declined. The characteristic patterns of the values of both isotopes indicates that the signatures of different water masses are associated with various frontal systems and/or water masses across the transect. The signature of the Polar Front at around latitude 50◦S shows the specific response of the isotopic values (δ18O and δ13C) of G. bulloides. Such a response beyond 50◦S latitude is ascribable to the general decrease in the ambient temperature, resulting in a continuous increase in δ18O values, while δ13C values decrease as a result of reduced photosynthesis in regions approaching higher latitudes owing to low light penetration. To further corroborate our results, those of many such transects from geographically distinct regions need to be studied for isotopic variations in the calcareous shells of planktonic foraminiferal species. The results have the potential to be used as a proxy to assess the movement of frontal systems in southern high latitude regions.
Źródło:
Oceanologia; 2012, 54, 2
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Limitation of lignin derivatives as biomarkers of land derived organic matter in the coastal marine sediments
Autorzy:
Pempkowiak, J.
Powiązania:
https://bibliotekanauki.pl/articles/2079190.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
lignin oxidation
biomarker
stable carbon isotope
nonlinear analysis
Gdansk Bay
Southern Baltic Sea
coastal sediment
Opis:
Lignin oxidation products (vanillyl, syringil and cummaryl phenols), and δ13C were measured in a variety of land and marine samples collected in Inner Puck Bay – dominated by marine vascular plants, small river run-off, and shallow bottom, and in Gdańsk Bay – characterized by large river run-off, small marine vascular plants population, and the average depth exceeding euphotic zone. Both study areas are parts of the Gdańsk Basin, Southern Baltic. Typical δ13C values (δ13C = -28‰) and both composition and concentrations of lignin phenols were measured in samples originating from land. Small, yet easily measurable amounts of lignin phenols were found in marine vascular plants biomass (Σ8 = 90 µg/100 mg organic matter). The biomass was characterized by exceptionally high δ13C values (-12‰). No lignin phenols and typical δ13C values (-22‰) were measured in marine phytoplankton biomass. δ13C and both composition and content of lignin phenols in organic matter of surface sediments collected in the study area fall in the range marked by the end members. The proportion of land derived organic matter calculated using lignin phenols, or δ13C in Gdańsk Bay were comparable, while in Puck Bay they differed substantially. It was concluded that a) in areas with substantial bottom coverage with vascular plants the two end members approach, usually employed to establish the contribution of organic matter sources, is insufficient, b) organic matter originating from three sources: riverine, phytoplankton, and vascular plants contribute to sedimentary organic matter in Puck Bay with the respective proportion 30:40:30.
Źródło:
Oceanologia; 2020, 62, 3; 374-386
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Elemental and organic carbon proxies for redox conditions of the Oligocene formations in the Ropa Tectonic Window (Outer Carpathians, Poland) : palaeoenvironmental implications
Autorzy:
Wójcik-Tabol, P.
Powiązania:
https://bibliotekanauki.pl/articles/973585.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
organic matter
stable organic carbon isotope
trace metals
anoxia
Grybów Succession
Oligocene
Opis:
The Oligocene Grybów Succession is recognized as a counterpart of the anoxic Menilite Formation. Its comprehensive geochemical investigations are made in the key sections of the Ropa Tectonic Window (the Grybów Unit, Polish Outer Carpathians). The maceral assemblages, dominated by land-plant liptinite, vitrinite and intertinite, correspond to kerogen types II and III. A Tmax vs. HI diagram shows terrestrial kerogen type II with various additions of type III and algal kerogen type I. A variation in δ13Corg. (from –25.21 to –27.38‰) may have resulted from variations in the composition of organic matter (the content of terrestrial vs. marine organic matter), controlled by depositional setting (turbidite vs. hemipelagic). The highest TOC contents are associated with an enhanced influx of land-derived organic matter. The redox-sensitive trace elements positively correlate with TOC and TS contents. Redox conditions varied between oxic and anoxic, as was concluded from TOC-TS, V/(V+Ni) and U/Th. The turbidity currents might have ventilated the bottom waters, especially more efficiently in the proximal zone of turbidite sedimentation. Moreover, oxygenated bottom waters may have also affected the concentration of trace metals, owing to migration of the redox interface downward within the sediments.
Źródło:
Annales Societatis Geologorum Poloniae; 2017, 87, 1; 41-53
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
13C-urea breath test for detection of Helicobacter pylori and its correlation with endoscopic and histologic findings
Autorzy:
Hilker, E
Domschke, W.
Stoll, R.
Powiązania:
https://bibliotekanauki.pl/articles/71128.pdf
Data publikacji:
1996
Wydawca:
Polskie Towarzystwo Fizjologiczne
Tematy:
gastritis
gastric ulcer
infection
mucosa
endoscopical finding
duodenal ulcer
urea breath test
Helicobacter pylori
gastric carcinoma
lymphatic tissue
ulcer
stable isotope
histological finding
stomach
urease
malignant lymphoma
Źródło:
Journal of Physiology and Pharmacology; 1996, 47, 1
0867-5910
Pojawia się w:
Journal of Physiology and Pharmacology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zróżnicowanie zawartości pierwiastków śladowych w osadach torfowisk Wolbrom i Otrębowskie Brzegi odzwierciedleniem wpływu antropopresji
Variability of trace element concentrations in deposits of the Wolbrom and Otrębowskie Brzegi peatlands: a reflection of an anthropogenic impact
Autorzy:
Pawełczyk, Fatima
Okupny, Daniel
Michczyński, Adam
Powiązania:
https://bibliotekanauki.pl/articles/578347.pdf
Data publikacji:
2018
Wydawca:
Łódzkie Towarzystwo Naukowe
Tematy:
torf
pierwiastki śladowe
stabilne izotopy ołowiu
antropopresja
Polska Południowa
peat
trace elements
stable lead isotope
anthropogenic activity
Southern Poland
Opis:
W artykule zaprezentowano analizę geochemiczną profili torfowych z dwóch torfowisk, położonych w Polsce Południowej, dokumentujących przedział czasowy od okresu atlantyckiego (od 4900 BC Wolbrom i od 4200 BC Otrębowskie Brzegi) do czasów współczesnych. Jej wyniki poddano analizie statystycznej z użyciem programu PAST, celem porównania badanych torfowisk pod względem wpływu działalności człowieka oraz położenia w różnych zlewniach, z uwzględnieniem przeprowadzonych wcześniej analiz botanicznych, datowania radiowęglowego i ołowiem-210 oraz analizy składu izotopowego Pb. Koncentracja pierwiastków w badanych profilach torfowych zależała od rodzaju osadu i była mocno zróżnicowana, wahając się w przedziale od wartości niskich, zbliżonych do lokalnego tła geochemicznego, aż do ekstremalnie wysokich (w szczególności w przypadku metali ciężkich, takich jak cynk i ołów). Przeprowadzona analiza porównawcza pozwoliła na zaobserwowanie synchronicznego zapisu lokalnych, jak i regionalnych zmian składu chemicznego w dwóch torfowiskach, różniących się lokalizacją, litologią i rodzajem torfu.
A geochemical analysis was conducted on peat cores from two peatlands in Southern Poland that cover a time span from the Atlantic period (from 4900 BC in Wolbrom and from 4200 BC in Otrębowskie Brzegi) to modern times. The results were subjected to a statistical analysis using PAST software. The analysis was conducted taking into account previous botanical analyses, radiocarbon dating and lead-210 dating. The aim was to compare these two study sites in terms of their locations in different basins and anthropogenic activity. Elemental concentrations in the tested peat profiles were dependent on sediment type and their values range between very low (close to geochemical background values) and extremely high – especially in the case of heavy metals, like zinc and lead. The comparative analysis showed a synchronous record of local and regional changes of chemical composition in the two peatlands, which vary in terms of location, lithology and type of peat sediment.
Źródło:
Acta Geographica Lodziensia; 2018, 107; 175-190
0065-1249
Pojawia się w:
Acta Geographica Lodziensia
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 18

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