932 resultados para Language, Origin of.


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Apollinaris Mons is an isolated volcano on Mars straddling the boundary between the southern highlands and the northern plains. One of its most distinctive features is its massive fan-shaped deposit that extends from a breach on its summit to distances of more than 150 km and drapes its entire southern flank. The composition and formation mechanism of these deposits remains controversial. We investigate the radar properties of the fan deposits (FD) of Apollinaris Mons using low-frequency sounding radar data in combination with high-resolution images and crater-size frequency analysis to constrain their inner shape and bulk composition. Our analysis indicates that the FD attains an irregular thickness and is gradually thinner towards their lateral margins. The crater-size frequency analysis shows that they may have undergone repeated resurfacing, which is suggestive of long-term evolution. Our analysis of Shallow Radar (SHARAD) radargrams traversing different sections of the FD reveals multiple and different subsurface interfaces among the radargrams crossing the thinnest part, which suggests a layered and complex inner shape. Our estimates for the bulk real part of the dielectric constant of the FD ranges from 3 to 5, which is consistent with an icy-silicate mixture or pyroclastic composition. Therefore, we conclude that lahars or pyroclastic flows are the most likely mechanism that created the FD, yet we cannot rule out additional contributions from lava flows. A combination of multiple processes is also possible since the deposits appear to have been modified by fluvial processes at a later stage of their formation.

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Very recently, the ATLAS and CMS Collaborations reported diboson and dijet excesses above standard model expectations in the invariant mass region of 1.8–2.0 TeV. Interpreting the diboson excess of events in a model independent fashion suggests that the vector boson pair production searches are best described by WZ or ZZ topologies, because states decaying into W+W− pairs are strongly constrained by semileptonic searches. Under the assumption of a low string scale, we show that both the diboson and dijet excesses can be steered by an anomalous U(1) field with very small coupling to leptons. The Drell–Yan bounds are then readily avoided because of the leptophobic nature of the massive Z′ gauge boson. The non-negligible decay into ZZ required to accommodate the data is a characteristic footprint of intersecting D-brane models, wherein the Landau–Yang theorem can be evaded by anomaly-induced operators involving a longitudinal Z. The model presented herein can be viewed purely field-theoretically, although it is particularly well motivated from string theory. Should the excesses become statistically significant at the LHC13, the associated Zγ topology would become a signature consistent only with a stringy origin.

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We show that global properties of gauge groups can be understood as geometric properties in M-theory. Different wrappings of a system of N M5-branes on a torus reduce to four-dimensional theories with AN−1 gauge algebra and different unitary groups. The classical properties of the wrappings determine the global properties of the gauge theories without the need to impose any quantum conditions. We count the inequivalent wrappings as they fall into orbits of the modular group of the torus, which correspond to the S-duality orbits of the gauge theories.

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[Philadelphia], Univ., Diss., [1914]

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3. "Plan d'ensemble d'une enquête sur les attitudes generales de la population allemande a l'egard de la France et leurs consequences en ce qui concerne l'orientation des emissions en langue allemande de la radiodiffusion francaise", 18.05.1953. Typoskript, 7 Blatt; 4. "Note" Über Methode, Forschungsrichtung und Reichweite der Ergebnisse der Untersuchung; 18.05.1953; Typoskript, 7 Blatt; 5. "Note" Über Geschichte und Tätigkeit des Instituts für Sozialforschung; 18.05.1953; Typoskript, 5 Blatt; 6. Memorandum des Instituts zu Verfahren und ergebnissen der Untersuchung; 1954 [?]; Typoskript, 2 Blatt; 7.-17. Décamps, Jacques: Memoranden; 7. Memorandum, 12.09.1953; Typoskript, 1 Blatt; 8. "Memorandum re: Besprechung in Bad Godesberg in Bezug auf die französische Studie, am 04.September 1953", 10.09.1953. Typoskript, 1 Blatt; 9. "Memorandum re: Vorhaben des 'Centre d'Etudes Sociologiques, Paris', eine deutsch-französische Arbeitsgemeinschft für die Durchführung von Gemeindestudien zu gründen", 15.06.1953. Typoskript, 1 Blatt; 10. "Memorandum über den Besuch von M. Jean L. Pelosse, Centre d'Etudes sociologiques Paris", 12.06.1953. Typoskript, 3 Blatt; 11. "Bericht über die 'Journées d'Etudes eurropéennes sur la Population' Paris, 21., 22. und 23. Mai 1953", 01.06.1953; 12. "Bericht über den Stand der Verhandlungen mit dem Französischen Auswärtigen Amt und dem französischem Rundfunk. Besprechungen in Paris am 27. und 28. Mai 1953", 01.06.1953. Typoskript, 2 Blatt; 13. Angaben für Max Horkheimer zur Übergabe von Memoranden, Projektbeschreibungen und Briefentwürfen, Mai 1953; Typoskript, 1 Blatt; 14. "Bericht über das 'Institut National d'Etudes Démographiques'", 07.05.1953. Typoskript, 4 Blatt; 15. "Memorandum re: Methode der Gruppendiskussion", 04.05.1953. Typoskript, 1 Blatt; 16. "Besprechung im 'Institut francaise d'Opinion Publique, Paris' und bei der hohen Behörde Luxemburg" 30.04.1953; 17. "Besprechung im Auswärtigen Amt und bei dem französischen Rundfunk", 29.04.1953. Typoskript, 6 Blatt; 18. Horkheimer, Max: 1 Brief an den französischen Botschafter in der Bundesrepublik Deutschland, ohen Ort, ohne Datum; Typoskript, 1 Blatt; 19. Radiodiffusion-Télévision Francaise, le Directeur: 1 Briefabschrift an Jacques Décamps, Paris, 09.03.1954; 1 Blatt; 20. Plessner, Helmuth: 1 Brief an den französischen Außenminister, ohne Ort, 18.05.1953; 1 Blatt; 21. Plessner, Helmuth: 1 Brief an Radiodiffusion Francaise, ohne Ort, 18.05.1953; 1 Blatt; 22. Plessner, Helmuth: 1 Brief an den Ministerialrat der Sektion "Agences et Radio" im französischem Außenministerium, ohne Ort, 18.05.1953; 1 Blatt; "The Effectiveness of Candid versus Evasive German-Language Broadcasts of the Voice of America. Final Report", 1953. Typoskript, gebunden, 432 Blatt;

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This study deals with the mineralogical variability of siliceous and zeolitic sediments, porcellanites, and cherts at small intervals in the continuously cored sequence of Deep Sea Drilling Project Site 462. Skeletal opal is preserved down to a maximum burial depth of 390 meters (middle Eocene). Below this level, the tests are totally dissolved or replaced and filled by opal-CT, quartz, clinoptilolite, and calcite. Etching of opaline tests does not increase continously with deeper burial. Opal solution accompanied by a conspicuous formation of authigenic clinoptilolite has a local maximum in Core 16 (150 m). A causal relationship with the lower Miocene hiatus at this level is highly probable. Oligocene to Cenomanian sediments represent an intermediate stage of silica diagenesis: the opal-CT/quartz ratios of the silicified rocks are frequently greater than 1, and quartz filling pores or replacing foraminifer tests is more widespread than quartz which converted from an opal-CT precursor. As at other sites, there is a marked discontinuity of the transitions from biogenic opal via opal-CT to quartz with increasing depth of burial. Layers with unaltered opal-A alternate with porcellanite beds; the intensity of the opal-CT-to-quartz transformation changes very rapidly from horizon to horizon and obviously is not correlated with lithologic parameters. The silica for authigenic clinoptilolite was derived from biogenic opal and decaying volcanic components.

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CH4 and CO2 species in pore fluids from slope sediments off Guatemala show extreme 13C-enrichment (d13C of -41 and +38 per mil, respectively) compared with the typical degree of 13C-enrichment in pore fluids of DSDP sediments (d13C of - 60 and + 10 per mil). These unusual isotopic compositions are believed to result from microbial decomposition of organic matter, and possibly from additional isotopic fractionation associated with the formation of gas hydrates. In addition to the isotopic fractionation displayed by CH4 and CO2, the pore water exhibits a systematic increase in d18O with decrease in chlorinity. As against seawater d18O values of 0 and chlorinity of 19 per mil, the water collected from decomposed gas hydrate from Hole 570 had a d18O of + 3.0 per mil and chlorinity of 9.5 per mil. The isotopic compositions of pore-fluid constituents change gradually with depth in Hole 568 and discontinuously with depth in Hole 570.

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The sediments recovered on Deep Sea Drilling Project Leg 54 appear to be mixtures of the normal pelagic sediments of the area and hydrothermally produced manganese and iron phases. The latter are mineralogically and chemically very similar to phases recovered from surficial sampling of the mounds. The hydrothermal nontronite which is approximately 15 meters thick in the three holes is essentially free of carbonate or detrital contaminants. The basal sediments are similar to the carbonate oozes presently being deposited in the region, but are enriched in Mn and Fe. This enrichment appears to be the result of hydrothermal deposition that took place at or near the spreading center and may not be associated with the mounds formation. Three different hypotheses for the formation of the nontronite layer and the mounds deposits are considered. An initial deposition of a widespread nontronite layer and subsequent diapiric-like movement of the layer into carbonates could account for the observed stratigraphy; however, if this be correct, analogous deposits should be present in other DSDP sites. The second hypothesis - replacement of the normal sediments by nontronite - may be feasible, but the high purity of the nontronite requires dissolution and removal of refractory elements. The third hypothesis, metal deposition in an advancing oxidation gradient, is compatible with submersible observations of the mounds; however, it can account only for the high purity of the nontronite by very rapid deposition of the hydrothermal phases.

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Drilling at Site 534 in the Blake-Bahama Basin recovered 268 m of Lower Cretaceous, Berriasian to Hauterivian, pelagic carbonates, together with volumetrically minor intercalations of claystone, black shales, and terrigenous and calcareous elastics. Radiolarian nannofossil pelagic carbonates accumulated in water depths of about 3300 to 3650 m, below the ACD (aragonite compensation depth) but close to the CCD (calcite compensation depth). Radiolarian abundance points to a relatively fertile ocean. In the Hauterivian and Barremian, during times of warm, humid climate and rising sea level, turbiditic influxes of both terrigenous and calcareous sediments, and minor debris flows were derived from the adjacent Blake Plateau. The claystones and black shales accumulated on the continental rise, then were redeposited onto the abyssal plain by turbidity currents. Dark organic-rich and pale organic-poor couplets are attributed to climatic variations on land, which controlled the input of terrigenous organic matter. Highly persistent, fine, parallel lamination in the pelagic chalks is explained by repeated algal "blooms." During early diagenesis, organic-poor carbonates remained oxygenated and were cemented early, whereas organic-rich intervals, devoid of burrowing organisms, continued to compact later in diagenesis. Interstitial dissolved-oxygen levels fluctuated repeatedly, but bottom waters were never static nor anoxic. The central western Atlantic in the Lower Cretaceous was thus a relatively fertile and wellmixed ocean basin.