Climate variability and ice-sheet dynamics during the last three glaciations

AbstractA composite North Atlantic record from DSDP Site 609 and IODP Site U1308 spans the past 300,000 years and shows that variability within the penultimate glaciation differed substantially from that of the surrounding two glaciations. Hematite-stained grains exhibit similar repetitive down-core variations within the Marine Isotope Stage (MIS) 8 and 4–2 intervals, but little cyclic variability within the MIS 6 section. There is also no petrologic evidence, in terms of detrital carbonate-rich (Heinrich) layers, for surging of the Laurentide Ice Sheet through the Hudson Strait during MIS 6. Rather, very high background concentration of iceberg-rafted debris (IRD) indicates near continuous glacial meltwater input that likely increased thermohaline disruption sensitivity to relatively weak forcing events, such as expanded sea ice over deepwater formation sites. Altered (sub)tropical precipitation patterns and Antarctic warming during high orbital precession and low 65°N summer insolation appear related to high abundance of Icelandic glass shards and southward sea ice expansion. Differing European and North American ice sheet configurations, perhaps aided by larger variations in eccentricity leading to cooler summers, may have contributed to the relative stability of the Laurentide Ice Sheet in the Hudson Strait region during MIS 6

High-resolution Quaternary record of marine organic carbon content in the hemipelagic sediments of the Japan Sea from bromine counts measured by XRF core scanner

Abstract The marine organic carbon content in sediments is a useful tool for reconstructing past productivity in the ocean. Bromine has been proposed as a useful proxy for marine organic carbon, since bromine is more concentrated in marine organic matter compared to terrestrial organic matter. Here, we present a high-resolution Quaternary record of marine organic carbon in the hemipelagic sediments of the Japan Sea obtained during Integrated Ocean Drilling Program (IODP) Expedition 346. We measured the bromine content in the sediments using an XRF core scanner (ITRAX). The total organic carbon content, total nitrogen, and stable carbon isotope values were also measured for discrete samples from the same sediments. The total organic carbon/total nitrogen ratio and the stable carbon isotope ratio of the total organic carbon are used to estimate the marine organic carbon content within the total organic carbon. The Br counts and marine organic carbon content show a high correlation, which we used to construct a calibration equation of the marine organic carbon content from the Br counts. Using the calibration equation, we reconstructed the changes in the marine organic carbon content during the Quaternary with a time resolution of ~ 50 years using sediment cores from IODP Site U1424 in the east central Japan Sea. The method to estimate the marine organic carbon content from the Br counts measured by the XRF core scanner proposed in this paper will be a useful tool to reconstruct the organic carbon content with high resolution and high speed

The Y4-RNA fragment, a potential diagnostic marker, exists in saliva

The 94-nt full-length Y4-RNA is thought to have roles in the initiation of DNA replication and RNA quality control. Although its 31/32-nt fragment also exists abundantly in plasma, little is known about its physiological role. Since the 31/32-nt Y4-RNA fragment in sera is reported to be more abundant in patients with coronary artery disease than healthy persons, the fragment may have a potential for a diagnostic and/or prognostic biomarker for some diseases regardless of its functionality. As a step toward further investigation of its potential utility, we examined if the 31/32-nt Y4-RNA fragment also exists in saliva that can be obtained noninvasively, and showed that, in addition to the 31/32-nt fragment, 14- and 11-nt Y4-RNA fragments are present in all saliva RNA samples from four healthy persons. We established a PCR method to accurately quantitate the amount of the 31/32-nt Y4-RNA fragment, and estimated its amount in saliva of healthy persons to be 0.06 ± 0.04 fmol per nanogram of saliva RNA. We also tried to develop an easier quantitation method using a DNA molecular beacon. Keywords: Y4-RNA fragment, Saliva RNA, Diagnostic/prognostic marker, Next-generation sequencing, RT-PCR, Molecular beaco

Climate variability and ice-sheet dynamics during the last three glaciations

A composite North Atlantic record from DSDP Site 609 and IODP Site U1308 spans the past 300,000 years and shows that variability within the penultimate glaciation differed substantially from that of the surrounding two glaciations. Hematite-stained grains exhibit similar repetitive down-core variations within the Marine Isotope Stage (MIS) 8 and 4–2 intervals, but little cyclic variability within the MIS 6 section. There is also no petrologic evidence, in terms of detrital carbonate-rich (Heinrich) layers, for surging of the Laurentide Ice Sheet through the Hudson Strait during MIS 6. Rather, very high background concentration of iceberg-rafted debris (IRD) indicates near continuous glacial meltwater input that likely increased thermohaline disruption sensitivity to relatively weak forcing events, such as expanded sea ice over deepwater formation sites. Altered (sub)tropical precipitation patterns and Antarctic warming during high orbital precession and low 65°N summer insolation appear related to high abundance of Icelandic glass shards and southward sea ice expansion. Differing European and North American ice sheet configurations, perhaps aided by larger variations in eccentricity leading to cooler summers, may have contributed to the relative stability of the Laurentide Ice Sheet in the Hudson Strait region during MIS 6

Selected Chapters on Baseball History in the World and the Czech Republic

Vybrané kapitoly z historie baseballu ve světě a ČR Selected chapters from baseball history in the world and the Czech Republic Cíl práce: Zpracovat prapočátky baseballu a vyřešit otázku původu baseballu, zmínit nejvýznamnější momenty ve světové historii baseballu, analyzovat historii a současnou situaci baseballu v ČR a navrhnout možnosti zlepšení situace v Česku. Metoda: Pro zpracování základních informací z historie baseballu byla v největším rozsahu použita metoda přímá, induktivní a deduktivní. Dále pak bylo použito metody diachronní progresivní, kvantitativní a komparativní. Výsledky: Mohou pomoci seznámit se s baseballovým odvětvím, blíže pak s jeho celosvětovým vývojem. Klíčová slova: Baseball, Major league baseball, American league, Nationalleague, liga, tým, hráč, USA. V Praze, dne 31. srpna 2006. 1KinantropologieFaculty of Physical Education and SportFakulta tělesné výchovy a sport

Construction of perfectly continuous records of physical properties for dark-light sediment sequences collected from the Japan Sea during Integrated Ocean Drilling Program Expedition 346 and their potential utilities as paleoceanographic studies

Abstract Establishment of sedimentary sequence is essential for the interpretation of the sedimentary records. Integrated Ocean Drilling Program (IODP) Expedition (Exp.) 346 drilled high-quality sediment archives with more than three holes each at nine sites that enable us to establish continuous sedimentary sequences through splicing technique. After extensive efforts to replace the disturbed, missed, or duplicated intervals found in spliced sediment sequences constructed onboard during IODP Exp. 346 to the corresponding undisturbed intervals, nearly perfectly continuous sediment columns and physical property records for the Pleistocene intervals of Sites U1422-U1427 and U1430 collected from the Japan Sea have been established. Same kind of efforts to correct the shipboard splices were also achieved for Plio-Miocene intervals at Sites U1425 and U1430. The continuous records established for these sites will allow a much more detailed understanding of the long-term variability in East Asian paleoclimate and North Pacific oceanography