Hyalotekite, (Ba,Pb,K)(4)(Ca,Y)(2)Si-8(B,Be)(2)(Si,B)(2)O28F, a Tectosilicate Related to Scapolite: New Structure Refinement, Phase Transitions and a Short-Range Ordered 3B Superstructure

Hyalotekite, a framework silicate of composition (Ba,Pb,K)(4)(Ca,Y)(2)Si-8(B,Be)(2) (Si,B)(2)O28F, is found in relatively high-temperature(greater than or equal to 500 degrees C) Mn skarns at Langban, Sweden, and peralkaline pegmatites at Dara-i-Pioz, Tajikistan. A new paragenesis at Dara-i-Pioz is pegmatite consisting of the Ba borosilicates leucosphenite and tienshanite, as well as caesium kupletskite, aegirine, pyrochlore, microcline and quartz. Hyalotekite has been partially replaced by barylite and danburite. This hyalotekite contains 1.29-1.78 wt.% Y2O3, equivalent to 0.172-0.238 Y pfu or 8-11% Y on the Ca site; its Pb/(Pb+Ba) ratio ranges 0.36-0.44. Electron microprobe F contents of Langban and Dara-i-Pioz hyalotekite range 1.04-1.45 wt.%, consistent with full occupancy of the F site. A new refinement of the structure factor data used in the original structural determination of a Langban hyalotekite resulted in a structural formula, (Pb1.96Ba1.86K0.18)Ca-2(B1.76Be0.24)(Si1.56B0.44)Si8O28F, consistent with chemical data and all cations with positive-definite thermal parameters, although with a slight excess of positive charge (+57.14 as opposed to the ideal +57.00). An unusual feature of the hyalotekite framework is that 4 of 28 oxygens are non-bridging; by merging these 4 oxygens into two, the framework topology of scapolite is obtained. The triclinic symmetry of hyalotekite observed at room temperature is obtained from a hypothetical tetragonal parent structure via a sequence of displacive phase transitions. Some of these transitions are associated with cation ordering, either Pb-Ba ordering in the large cation sites, or B-Be and Si-B ordering on tetrahedral sites. Others are largely displacive but affect the coordination of the large cations (Pb, Ba, K, Ca). High-resolution electron microscopy suggests that the undulatory extinction characteristic of hyalotekite is due to a fine mosaic microstructure. This suggests that at least one of these transitions occurs in nature during cooling, and that it is first order with a large volume change. A diffuse superstructure observed by electron diffraction implies the existence of a further stage of short-range cation ordering which probably involves both (Pb,K)-Ba and (BeSi,BB)-BSi.

DNA binding properties of oligodeoxynucleotides containing pyrrolidino C-nucleosides

We have incorporated pyrrolidino-C-nucleosides (pyrrolidino-pseudonucleosides) containing the base uracil and N-1-methyl uracil into oligodeoxynucleotides and compared their thermal duplex and triplex stabilities with unmodified or pseudouridine-containing oligodeoxynucleotides. We find relative destabilizations of triplex formation by ca. -13 to -1 degrees C per modification (relative to thymidine) in a strongly sequence dependent mode. Duplex formation is less destabilizing and more homogeneous with -4 to -2 degrees C per modification

Vapnikite Ca3UO6 – a new double-perovskite mineral from pyrometamorphic larnite rocks of the Jabel Harmun, Palestinian Autonomy, Israel

The new mineral species vapnikite, Ca3UO6, was found in larnite pyrometamorphic rocks of the Hatrurim Formation at Jabel Harmun in the Judean desert, Palestinian Autonomy, Israel. Vapnikite is an analogue of the synthetic ordered double-perovskite β-Ca3UO6 and is isostructural with the natural fluorperovskite – cryolite Na3AlF6. Vapnikite Ca3UO6 (P21/n,Z = 2, a = 5.739(1), b = 5.951(1), c = 8.312(1) Å, β = 90.4(1)°, V = 283.9(1) Å3) forms yellow-brown xenomorphic grains with a strong vitreous lustre. Small grains up to 20 – 30 m m in size are wedged between larnite, brownmillerite and ye'elimite. Vapnikite has irregular fracture, cleavage and parting were not observed. The calculated density is 5.322 g cm–3, the microhardness is VHN25 = 534 kg mm–2 (mean of seven measurements) corresponding to the hardness of ~5 on the Mohs scale. The crystal structure of vapnikite Ca3UO6 differs from that of its synthetic analogue β-Ca3UO6 by having a larger degree of Ca, U disorder. Vapnikite formed at the high-temperature retrograde stage of pyrometamorphism when larnite rocks were altered by fluids/melts of high alkalinity.

Twentieth Century Delta δC Variability in Surface Water Dissolved Inorganic Carbon Recorded by Coralline Algae in the Northern North Pacific Ocean and the Bering Sea

The oxygen isotopic composition and Mg/Ca ratios in the skeletons of long-lived coralline algae record ambient seawater temperature over time. Similarly, the carbon isotopic composition in the skeletons record delta(13)C values of ambient seawater dissolved inorganic carbon. Here, we measured delta(13)C in the coralline alga Clathromorphum nereostratum to test the feasibility of reconstructing the intrusion of anthropogenic CO(2) into the northern North Pacific Ocean and Bering Sea. The delta(13)C was measured in the high Mgcalcite skeleton of three C. nereostratum specimens from two islands 500 km apart in the Aleutian archipelago. In the records spanning 1887 to 2003, the average decadal rate of decline in delta(13)C values increased from 0.03% yr(-1) in the 1960s to 0.095% yr(-1) in the 1990s, which was higher than expected due to solely the delta(13)C-Suess effect. Deeper water in this region exhibits higher concentrations of CO(2) and low delta(13)C values. Transport of deeper water into surface water (i.e., upwelling) increases when the Aleutian Low is intensified. We hypothesized that the acceleration of the delta(13)C decline may result from increased upwelling from the 1960s to 1990s, which in turn was driven by increased intensity of the Aleutian Low. Detrended delta(13)C records also varied on 4-7 year and bidecadal timescales supporting an atmospheric teleconnection of tropical climate patterns to the northern North Pacific Ocean and Bering Sea manifested as changes in upwelling.

Beiträge zur Entwicklungsgeschichte des Judentums, von ca. 400 v. Chr. bis ca. 1000 n. Chr.

von D. Chwolson

Na 1 Nachlass Max Horkheimer, 707 - "German Refugees from Eastern Zone" (p. IX 183.1-2 - IX 184.2-18)

"German Refugees from the Eastern Zone" 1952; 1. "Outline of a Pilot Study of German Refugees from the Eastern Zone Who are presently in Berlin" a) Typoskript, 4 Blatt; b) Typoskript, 3 Blatt; 2. "Budget for a Pilot Study of German Refugees from the Eastern Zone in Berlin" a) 2 Blatt; b) 1 Blatt; c) 1 Blatt; d) 1 Blatt; "Universität und Gesellschaft" 1952-1956; 1. "Universität und Gesellschaft" Teil III: Expertenbefragung. Forschungsbericht, 1953; als Typoskript vervielfältigt und gebunden, 77 Blatt; 2.-7. Allgemeine Darstellung der Untersuchungen; 2. "Einige wichtige Ergebnisse der Universitätsstudie", 1956. Als Typoskript vervielfältigt, 5 Blatt; 3. "Vorläufige Gliederung für den Bericht der Hochschul-Untersuchung" 2 Blatt; 4. "The German University of Today. Progress Report on a Research Project" 02.11.1955 a) Typoskirpt, 12 Blatt; b) Typoskript mit handschriftlichen Korrekturen, 12 Blatt; 5. "The German University of Today. A Progress Report on a Research Project" a) Typoskript, 7 Blatt; b) Typoskript mit handschriftlichen Korrekturen, 8 Blatt; c) Typoskirpt mit handschriftlichen Korrekturen, 12 Blatt; 6. "Funktion und Wirklichkeit der Universität heute. Zwischenbericht über drei Studien des Instituts für Sozialforschung an der Johann Wolfgang Goethe- Universität". Typoskript, 25 Blatt; 7. "Pläne einer Untersuchung über die Vorstellung von der Finktion der heutigen deutschen Universität bei bestimmten Personenkreisen" a) Typoskirpt, 11 Blatt; b) Typoskript, 11 Blatt; 8.-10. Studentenbefragung; 8. Fagebogen zur Umfrage "Warum studieren Studenten?", als Typoskript vervielfältigt, 19 Blatt; 9. "The Economic Situation of Students at the Johann Wolfgang Goethe- University in Frankfurt am Main" Resultate der Umfrage vom Winter 1952/43; Januar 1956; a) Typoskript, 43 Blatt; b) 43 Blatt; 10. "Students and Parentl Influence. Results of a Survey" a) Typoskript, 25 Blatt; b) Typoskript mit handschriftlichen Korrekturen von Frederick Pollock, 25 Blatt; 11.-14. Aktennotizen; 11. "Bericht über die Verhandlungen zwischen Herrn Professor Baumgarten, Tenbruck und Habermas am 12.12.1956 im Institut für vergleichende Sozialwissenschaften in Stuttgart. Betreff: Professorenstudie" 13.13.1956 vermutlich 13.03.1956. Typoskript, 2 Blatt; 12. Gembardt, Ulrich: Aktennotiz zur Hochschuluntersuchung. 23.05.1955, Typoskript, 3 Blatt; 13. Gembardt, Ulrich: Bemerkungen zur Aktennotiz vom 23.05.1955, Typoskript, 2 Blatt; 14. "Aktennotiz über die Hochschul-Forschungsprojekte des Göttinger Soziologischen Seminars und des Frankfurter Institut für Sozialforschung, die deim Hauptausschuß der Deutschen Forschungsgemeinschaft am 1. August 1953 zur Finanzierung vorgelegt werden" 20.07.1953. Typoskript, 2 Blatt; 15.-18. Briefe; 15. Löwenthal, Leo: 1 Brief mit Unterschrift an MAx Horkheimer, New York, 20.01.1955, 3 Blatt; 16. Horkheimer, Max [?]: 1 Brief an Chauncy D. Harris, ohne Ort, Januar 1955; a) Typoskirpt, 1 Blatt; b) Typoskirpt mit handschriftlichen Korrekturen, 1 Blatt; c) Typoskirpt mit handschriftlichen Korrekturen, 1 Blatt; d) Typoskirpt, 1 Blatt; 17. Horkheimer, Max: Drei gleichlautende Briefe an die Rektoren der Universität Bonn, Heidelberg und Koel, ohne Ort, 15.11.1953; a) Typoskript, 6 Blatt; b) Typoskript mit eigenhändigen KOrrekturen, 3 Blatt; 18. Plessner, Helmuth: 1 Brief mit Unterschrift mit Beilage an Max Horkheimer, Göttingen 02.07.1953, 4 Blatt;

Na 1 Nachlass Max Horkheimer, 564 - Korrespondenzen u.a. mit Alice H. Maier und Leo Löwenthal (p. VI 27, 254-402)

Briefwechsel zwischen Max Horkheimer und Alice H. Maier; 5 Briefe an Maurice und Carolyn Tumarkin von Max Horkheimer, 1957/1964; 3 Briefe zwischen Alice H. Maier und H. P. Edelman, 1957/1963; 2 Briefe von Alice H. Maier an Friedrich Pollock, 1960/1966; 2 Briefe von Max Horkheimer an The Diners Club (New York), 1965; 1 Brief an Patricia und Edward R. Wilbur von Alice H. Maier, 17.05.1965; 2 Briefe von Max Horkheimer an Patricia und Edward R. Wilbur, 1964; 2 Briefe zwischen Alice H. Maier und Alfred L. Copley, 1965; 5 Briefe zwischen William C. Kirkwood und Max Horkheimer, 1964; 2 Briefe von Max Horkheimer an Ulla Posnansky, 1964; 1 Brief an Leo Löwenthal von Max Horkheimer, 23.06.1964; 1 Brief von Max Horkheimer an Amerino Lionetti, 03.06.1964; 10 Briefe zwischen Herbert Marcuse und Max Horkheimer, 1935 - 1936; 1 Brief von R. Piper an Herbert Marcuse, 26.03.1936;

Great Barrier Reef coral element/Ca and stable isotope data and U-Th ages from IODP Expedition 325

Tropical south-western Pacific temperatures are of vital importance to the Great Barrier Reef (GBR), but the role of sea surface temperatures (SSTs) in the growth of the GBR since the Last Glacial Maximum remains largely unknown. Here we present records of Sr/Ca and d18O for Last Glacial Maximum and deglacial corals that show a considerably steeper meridional SST gradient than the present day in the central GBR. We find a 1-2 °C larger temperature decrease between 17° and 20°S about 20,000 to 13,000 years ago. The result is best explained by the northward expansion of cooler subtropical waters due to a weakening of the South Pacific gyre and East Australian Current. Our findings indicate that the GBR experienced substantial meridional temperature change during the last deglaciation, and serve to explain anomalous deglacial drying of northeastern Australia. Overall, the GBR developed through significant SST change and may be more resilient than previously thought.

Dinoflagellate cyst assemblages, oxygen isotope records of foraminifera, and alkenone and Mg/Ca-based SST estimates for the time interval 3.40-3.18 Ma (Late Pliocene) from five North Atlantic and Caribbean sediment cores

The early Late Pliocene (3.6 to ~3.0 million years ago) is the last extended interval in Earth's history when atmospheric CO2 concentrations were comparable to today's and global climate was warmer. Yet a severe global glaciation during marine isotope stage (MIS) M2 interrupted this phase of global warmth ~3.30 million years ago, and is seen as a premature attempt of the climate system to establish an ice-age world. Our geochemical and palynological records from five marine sediment cores along a Caribbean to eastern North Atlantic transect show that increased Pacific-to-Atlantic flow via the Central American Seaway weakened the North Atlantic Current (NAC) and attendant northward heat transport prior to MIS M2. The consequent cooling of the northern high latitude oceans permitted expansion of the Greenland ice sheet during MIS M2, despite near-modern atmospheric CO2 concentrations. Before and after MIS M2, heat transport via the NAC was crucial in maintaining warm climates comparable to those predicted for the end of this century.