993 resultados para 7139-204


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This study investigates the landscape evolution and soil development in the loess area near Regensburg between approximately 6000-2000 yr BP (radiocarbon years), Eastern Bavaria. The focus is on the question how man and climate influenced landscape evolution and what their relative significance was. The theoretical background concerning the factors that controlled prehistoric soil erosion in Middle Europe is summarized with respect to rainfall intensity and distribution, pedogenesis, Pleistocene relief, and prehistoric farming. Colluvial deposits , flood loams, and soils were studied at ten different and representative sites that served as archives of their respective palaeoenvironments. Geomorphological, sedimentological, and pedological methods were applied. According to the findings presented here, there was a high asynchronity of landscape evolution in the investigation area, which was due to prehistoric land-use patterns. Prehistoric land use and settlement caused highly difIerenciated phases of morphodynamic activity and stability in time and space. These are documented at the single catenas ofeach site. In general, Pleistocene relief was substantially lowered. At the same time smaller landforms such as dells and minor asymmetric valleys filled up and strongly transformed. However, there were short phases at many sites, forming short lived linear erosion features ('Runsen'), resulting from exceptional rainfalls. These forms are results of single events without showing regional trends. Generally, the onset of the sedimentation of colluvial deposits took place much earlier (usually 3500 yr BP (radiocarbon) and younger) than the formation of flood loams. Thus, the deposition of flood loams in the Kleine Laaber river valley started mainly as a consequence of iron age farming only at around 2500 yr BP (radiocarbon). A cascade system explains the different ages of colluvial deposits and flood loams: as a result of prehistoric land use, dells and other minor Pleistocene landforms were filled with colluvial sediments. After the filling of these primary sediment traps , eroded material was transported into flood plains, thus forming flood loams. But at the moment we cannot quantify the extent ofprehistoric soil erosion in the investigation area. The three factors that controlled the prehistoric Iandscapc evolution in the Ioess area near Regensburg are as follows: 1. The transformation from a natural to a prehistoric cultural landscape was the most important factor: A landscape with stable relief was changed into a highly morphodynamic one with soil erosion as the dominant process of this change. 2. The sediment traps of the pre-anthropogenic relief determined where the material originated from soil erosion was deposited: either sedimentation took place on the slopes or the filled sediment traps of the slopes rendered flood loam formation possible. Climatic influence of any importance can only be documented as the result of land use in connection with singular and/or statistic events of heavy rainfalls. Without human impact, no significant change in the Holocene landscape would have been possible.

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Contenido: El tiempo como medida de la primera esfera en la Física de Aristóteles / Marcelo L. Imperiale – Verdad, tiempo y justicia. Un tema de la filosofía de Anselmo de Canterbury / Ubaldo Pérez Paoli – La aportación de Tomás de Aquino a la filosofía de la justicia / Carlos Ignacio Massini Correas – Libertad y naturaleza: la voluntad como naturaleza y como razón según Tomás de Aquino / Guillermo Eduardo Spiegel Sosa – La representación como desvelamiento en Tomás de Aquino / Patrica Moya C. – Las condiciones de una nueva teoría del ente natural tras la condena de 1277. La Physica de Walter Burley y sus peculiaridades / Olga L. Larre – Gewibheit und Wahrheit. Descartes’ Grundlegung der Ersten Philosophie / Wilhelm Metz – La noción aristotélico-tomista de verdad y su interpretación en “El ser y el tiempo” de Martin Heidegger / Silvana Filippi – Subjetivistas radicales y hermenéutica en la escuela austríaca de economía / Ricardo F. Crespo – Examen de los principios de la bioética contemporánea predominantes / Camilo Tale – Sguardi sulla fine dei tempi e sulle cose ultime. A proposito Della struttura escatologica del cristianísimo / Vittorio Possenti – Naturaleza teleológica: articulación entre ser, deber ser y virtud / Jorge Peña Vial -- ¿Qué es un doctor de la Iglesia? / Francisco Canals Vidal – Anotaciones sobre la recepción y la crítica de la metafísica tomista en el pensamiento contemporáneo / Mario Enrique Sacchi – Notas y comentarios -- Bibliografía

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The cosmic-ray positron and negatron spectra between 11 and 204 MeV have been measured in a series of 3 high-altitude balloon flights launched from Fort Churchill, Manitoba, on July 16, July 21, and July 29, 1968. The detector system consisted of a magnetic spectrometer utilizing a 1000-gauss permanent magnet, scintillation counters, and a lucite Čerenkov counter.

Launches were timed so that the ascent through the 100 g/cm2 level of residual atmosphere occurred after the evening geomagnetic cutoff transition. Data gathered during ascent are used to correct for the contribution of atmospheric secondary electrons to the flux measured at float altitude. All flights floated near 2.4 g/cm2.

A pronounced morning intensity increase was observed in each flight. We present daytime positron and negatron data which support the interpretation of the diurnal flux variation as a change in the local geomagnetic cutoff. A large diurnal variation was observed in the count rate of positrons and negatrons with magnetic rigidities less than 11 MV and is evidence that the nighttime cutoff was well below this value.

Using nighttime data we derive extraterrestrial positron and negatron spectra. The positron-to-total-electron ratio which we measure indicates that the interstellar secondary, or collision, source contributes ≾50 percent of the electron flux within this energy interval. By comparing our measured positron spectrum with the positron spectrum calculated for the collision source we derive the absolute solar modulation for positrons in 1968. Assuming negligible energy loss during modulation, we derive the total interstellar electron spectrum as well as the spectrum of directly accelerated, or primary, electrons. We examine the effect of adiabatic deceleration and find that many of the conclusions regarding the interstellar electron spectrum are not significantly altered for an assumed energy loss of up to 50 percent of the original energy.

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86. Reise FFS "Anton Dohrn", 13. Februar - 9. April 1978

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The oxovanadium phosphonates (VO(P-204)(2) and VO(P-507)(2)) activated by various alkylaluminums (AlR3, R = Et, i-Bu, n-Oct; HAIR(2), R = Et, i-Bu) were examined in butadiene (Bd) polymerization. Both VO(P-204)(2) and VO(P-507)(2) showed higher activity than those of classical vanadium-based catalysts (e.g. VOCl3, V(acac)(3)). Among the examined catalysts, the VO(P-204)(2)/Al(Oct)(3) system (I) revealed the highest catalytic activity, giving the poly(Bd) bearing M-n of 3.76 x 10(4) g/mol, and M-w/M-n ratio of 2.9, when the [Al]/[V] molar ratio was 4.0 at 40 degrees C. The polymerization rate for I is of the first order with respect to the concentration of monomer. High thermal stability of I was found, since a fairly good catalytic activity was achieved even at 70 degrees C (polymer yield > 33%); the M-n value and M-w/M-n, ratio were independent of polymerization temperature in the range of 40-70 degrees C. By IR and DSC, the poly(Bd)s obtained had high 1,2-unit content (> 65%) with atactic configuration. The 1,2-unit content of the polymers obtained by I was nearly unchanged, regardless of variation of reaction conditions, i.e. [Al]/[V], ageing time, and reaction temperature, indicating the high stability of stereospecificity of the active sites.

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Servicios registrales

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The Miller Family Papers consist of notes on the Miller, Cathcart, and Roddey families, genealogical data on the Lindsay, Stewart, and McCaughrin families, and an American Civil War reminiscence of William Joseph Miller entitled, “My Experience as a Soldier in the Confederate Army. Written at the Request of Barnette, My Only Living Daughter.” Miller served in the 12th Regiment, South Carolina Volunteers of the Confederate Army.

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USFWS to Explore Canada Goose Management Strategies -- from a press release issued Aug. 3 by the US. Fish & Wildlife Service, written by Chris Tollefson. Anti-Trapping Measure Passes House Oregon Legislature Moves To Ensure Safety Of Its Citizens Against Cougars Acord Promoted Away From Wildlife Services New State Director US DA/APHIS in Mississippi is Kristina Godwin BOOk R e v i e w : "Living With Wildlife: How to Enjoy, Cope With, and Protect North America's Wild Creatures Around Your Home and Theirs," The California Center for Wildlife, with Diana Landau and Shelley Stump. San Francisco: A Sierra Club Book. 1994. 340 pp. + index $15.00. French Shepherds Protest Predators Rabbit Calicivirus Kills 65% of Rabbit Population Abstracts from the 2nd International Wildlife Management Congress, Hungary Crop Damage by Wildlife in Northern Ghana – O. I. Aalangdon* and A.S. Langyintuo, *Dept. of Renewable Natural Resources, University for Development Studies, Tamale Northern Region, Ghana Large Predators in Slovenia On the Way from Near Extermination to Overprotection and Back: Is Conservation Management of Large Predators in Cultural Landscapes Possible At All? -- M. Adamic, Chair of Wildlife Ecology, Biotechnical Faculty, University of Ljubljana, Slovenia Human-wolf Conflicts in the East Baltic: Past, Present, and Future -- Z. Andersone*, L. Balciauskas, and H. Valdmann., *Kemeri National Park, KemeriJurmala, Latvia Gray Wolf Restoration in the Northwestern United States -- E.E. Bangs*, J.A. Fontaine, D.W. Smith, C. Mack, and C. C. Niemeyer, *U.S. Fish & Wildlife Service, Helena, MT The Impact of Changing U.S. Demographics on the Future of Deer Hunting -- R. D. Brown, Wildlife & Fisheries Sciences, Texas A&M University, College Station, TX Management of Overabundant Marcropods in Nature Reserves: 6 Case Studies from Southeastern Australia -- G. Coulson, Dept. of Zoology,University of Melbourne,Parkville, Victoria, Australia