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71.
Zusammenfassung Der Transport radioaktiver Aerosol-Partikel durch die Atmosphäre wirft neue meteorologische Probleme auf. Eine kinematische Methode der Vorhersage von Trajektorien zeigt erhebliche Unterschiede gegenüber den Stromlinien. Die Ausbreitung von Partikelwolken ist eine Funktion der Vektorstreuung des Windfeldes und einem von der Zeit abhängigen Parameter. Der Massenaustausch zwischen der Troposphäre und der viel partikelreicheren Stratosphäre vollzieht sich vorwiegend in horizontaler Richtung im Niveau der Strahlströmungen. Einige Besonderheiten der Stratosphäre über dem tropischen Pazifik werden kurz beschrieben: die Aufspaltung der Tropopause über dem Äquator und die großen zeitlichen Änderungen der zonalen Windströmungen. Während die Gravitation und das Auswaschen durch Niederschläge vorwiegend gröbere Partikel (Durchmesser>2) zur Sedimentation bringen, fällt die Koagulation an Wolkenelementen hauptsächlich die kleinsten Partikel (<0.1 ) aus.
Summary The transport of radioactive particulate matter by the atmosphere introduces new meteorological problems. A kinematical method of forecasting air trajectories demonstrates substantial differences compared with stream-lines. The spread of particle clouds can be derived from the standard vector deviation of winds and a time-dependent parameter. Between the troposphere and the stratosphere with its much higher concentration of particles, the mass exchange occurs mainly in a horizontal direction near the jet-stream level. Some pecularities of the stratosphere above the Tropical Pacific are shortly described: the splitting of the tropopause above the equator, and the large time-variations of the zonal currents. While particles with a diameter of at least 2 micron are mainly deposited by gravitation and rain scavenging, coagulation with cloud droplets prefers particles below 0.1 micron.


Vortrag gehalten am 3. April 1959 auf der 7. Hauptversammlung der «Società Italiana di Geofisica e Meteorologia» (Genova: 3.–5. April 1959).  相似文献   
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Zusammenfassung Im westlichen Rheingaugebirge, am Südrand des Rheinischen Schiefergebirges, wurde durch kleintektonische und gefügekundliche Methoden der tektonische Großbau untersucht. Die vom nördlichen Schiefergebirge abweichende Fazies und die Nähe der Mitteldeutschen Schwelle beeinflußten das tektonische Bild des durch seinen Vergenzfächer, Abscherfaltungen, Schuppen und Achsenwölbungen charakterisierten Gebirges. - Eine strukturchronologische Gliederung zeigt die Persistenz der Bewegungen in den alten z.T. geosynklinalen Schwächezonen.  相似文献   
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Zusammenfassung Ausgehend von der herrschenden Vorstellung einer Transgression roter Liaskalke zur Zeit des oberen Unterlias über ein subaerisch verkarstetes Dachsteinkallerelief, untersuchte ich die Liassedimente in den Berchtesgadener Alpen eingehender und unternahm vergleichende Begehungen im östlichen Hagengebirge, im Steinernen Meer und in den Steinbrüchen von Adnet.Die Sedimente des Lias liegen in einer Graukalk- und einer abwechslungsreicheren Rotkalk-Fazies (F.Fabricius 1962) vor. Ammoniten zeigten, daß die Graukalkfazies einen Teil der Rotkalkfazies vertritt (im wesentlichen Sinemur). Auf die Ausbildung der Rotkalke hatten Mangelsedimentation, Subsolution und syngenetische Umlagerungen Einfluß.Normalerweise überlagert der Lias den Dachsteinkalk konkordant. Diskonforme Lagerung läßt sich durch submarine Kalklösung und synsedimentäre Spaltenbildung erklären. Die submarin entstandenen Zugspalten im Dachsteinkalk sind mit Rotkalksedimenten und Dachsteinkalktrümmern gefüllt. Die Bildungsdauer dieser, sich episodisch erweiternden Spalten ließ sich mit Ammoniten einschätzen.Argumente gegen die Annahme einer Transgression werden diskutiert.
Basing on the prevailing theory of a transgression of red Liassic limestones over a relief of Dachstein limestone affected by subaeric karstification, during late lower Liassic time, the author investigated the Liassic sediments of the Berchtesgaden Alps more in detail, comparing also with the eastern Hagen mountains, the Steinernes Meer and the quarries of Adnet.The Liassic sediments occur in two types of facies: gray limestone and a less uniform red limestone (Fabricius 1962). As ammonites prove, the gray limestone facies represents part of the red limestone facies (essentially Sinemur). The development of the red limestone was influenced by reduced sedimentation, subsolution and syngenetic rearrangement.In general, the Liassic strata are overlying the Dachstein limestone conformably, Disconformities may be explained by submarin limestone solution and synsedimentary formation of joints. The tension joints which developed by submarin action in the Dachstein limestone are filled up with red limestone sediments and debris of Dachstein limestone. It was possible to estimate the period of formation of these joints by ammonites.Arguments against the theory of a transgression are discussed.

Résumé En suivant la conception d'une transgression de calcaires liassiques rouges vers la fin du liassique inférieur sur un relief de calcaire «Dachstein» karstifié, l'auteur étudiait les dépôts liassiques des Alpes de Berchtesgaden plus en détail, y incluse une comparaison avec la montagne de Hagen orientale, le «Steinernes Meer» et les carrières d'Adnet.Les dépôts liassiques existent en deux faciès: des calcaires gris et des calcaires rouges plus variés (Fabricius 1962). Comme il est prouvé par des ammonites, le faciès de calcaires gris représente une partie du faciès de calcaires rouges (essentiellement Sinemur). Le développement des calcaires rouges était influencé par une sédimentation réduite, par la subsolution et par une réarrangement syngénétique.En général, les couches liassiques surmontent le calcaire «Dachstein» conformément. Discordance de stratification peut être expliquée par solution calcaire sous-marine et formation synsédimentaire de diaclases. Les diaclases d'extension formées en sous-marin dans le calcaire «Dachstein» sont remplies de dépôts de calcaire rouge et de débris du calcaire «Dachstein». La durée de formation de ces diaclases est à estimée par des ammonites.Des arguments contre la théorie d'une transgression sont discutés.

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Towards the end of the 19th century, geodetic observation techniques allowed it to create geodetic networks of continental size. The insight that big networks can only be set up through international collaboration led to the establishment of an international collaboration called “Central European Arc Measurement”, the predecessor of the International Association of Geodesy (IAG), in 1864. The scope of IAG activities was extended already in the 19th century to include gravity.At the same time, astrometric observations could be made with an accuracy of a few tenths of an arcsecond. The accuracy stayed roughly on this level, till the space age opened the door for milliarcsecond (mas) astrometry. Astrometric observations allowed it at the end of the 19th century to prove the existence of polar motion. The insight that polar motion is almost unpredictable led to the establishment of the International Latitude Service (ILS) in 1899.The IAG and the ILS were the tools (a) to establish and maintain the terrestrial and the celestial reference systems, including the transformation parameters between the two systems, and (b) to determine the Earth's gravity field.Satellite-geodetic techniques and astrometric radio-interferometric techniques revolutionized geodesy in the second half of the 20th century. Satellite Laser Ranging (SLR) and methods based on the interferometric exploitation of microwave signals (stemming from Quasars and/or from satellites) allow it to realize the celestial reference frame with (sub-)mas accuracy, the global terrestrial reference frame with (sub-)cm accuracy, and to monitor the transformation between the systems with a high time resolution and (sub-)mas accuracy. This development led to the replacement of the ILS through the IERS, the International Earth Rotation Service in 1989.In the pre-space era, the Earth's gravity field could “only” be established by terrestrial methods. The determination of the Earth's gravitational field was revolutionized twice in the space era, first by observing geodetic satellites with optical, Laser, and Doppler techniques, secondly by implementing a continuous tracking with spaceborne GPS receivers in connection with satellite gradiometry. The sequence of the satellite gravity missions CHAMP, GRACE, and GOCE allow it to name the first decade of the 21st century the “decade of gravity field determination”.The techniques to establish and monitor the geometric and gravimetric reference frames are about to reach a mature state and will be the prevailing geodetic tools of the following decades. It is our duty to work in the spirit of our forefathers by creating similarly stable organizations within IAG with the declared goal to produce the geometric and gravimetric reference frames (including their time evolution) with the best available techniques and to make accurate and consistent products available to wider Earth sciences community as a basis for meaningful research in global change. IGGOS, the Integrated Global Geodetic Observing System, is IAG's attempt to achieve these goals. It is based on the well-functioning and well-established network of IAG services.  相似文献   
77.
Alzheimer's disease (AD) is the most common form of dementia. Populations migrating from developing to industrialized countries seem to elicit a higher incidence and prevalence rate of AD, suggesting lifestyle and environmental factors to have a role in the pathophysiology of AD. One of its major neuropathological hallmarks is the deposition of Aβ peptides as amyloid plaques in the brain of AD patients. Aβ is proteolytically cleaved out of the larger amyloid precursor protein (APP). Cu and Mn are often found in drinking water and may have a neurotoxic potential. APP is involved in Cu homeostasis in mouse and man. In vitro observations and in vivo data obtained from APP mouse models provide strong evidence that APP overexpression enables intracellular Cu to be transported out of the cell. Disturbed metal‐ion homeostasis with elevated serum Cu levels occurs in Alzheimer and Down's patients and lowered levels in post‐mortem AD brain. We observed that bioavailable Cu has specific beneficial effects in an Alzheimer's disease mouse model. This should be regarded as a proof‐of‐concept for a prophylactic approach to overcome the observed CNS Cu deficiency in the brain of Alzheimer's disease patients. Manganism is a disorder with symptoms similar to that of Parkinson's disease. The precise mechanism how manganese can damage the nervous system is unknown. There is some evidence that iron and manganese may utilize similar transport systems. Epidemi ologic data strongly suggests that manganese enters the body primarily via inhalation and through the ingestion of manganese in drinking water.  相似文献   
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A high-resolution pollen record from a 5-m-long sediment core from the closed-lake basin Laguna Piusbi in the southern Colombian Pacific lowlands of Chocó, dated by 11 AMS14C dates that range from ca. 7670 to 22014C yr B.P., represents the first Holocene record from the Chocó rain forest area. The interval between 7600 and 610014C yr B.P. (500–265 cm), composed of sandy clays that accumulated during the initial phase of lake formation, is almost barren of pollen. Fungal spores and the presence of herbs and disturbance taxa suggest the basin was at least temporarily inundated and the vegetation was open. The closed lake basin might have formed during an earthquake, probably about 440014C yr B.P. From the interval of about 600014C yr B.P. onwards, 200 different pollen and spore types were identified in the core, illustrating a diverse floristic composition of the local rain forest. Main taxa are Moraceae/Urticaceae,Cecropia,Melastomataceae/Combretaceae,Acalypha, Alchornea,Fabaceae,Mimosa, Piper, Protium, Sloanea, Euterpe/Geonoma, Socratea,andWettinia.Little change took place during that time interval. Compared to the pollen records from the rain forests of the Colombian Amazon basin and adjacent savannas, the Chocó rain forest ecosystem has been very stable during the late Holocene. Paleoindians probably lived there at least since 346014C yr B.P. Evidence of agricultural activity, shown by cultivation ofZea maissurrounding the lake, spans the last 1710 yr. Past and present very moist climate and little human influence are important factors in maintaining the stable ecosystem and high biodiversity of the Chocó rain forest.  相似文献   
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Within the framework of the Tropospheric Research Programme (TFS) four working groups in Germany (University of Stuttgart, University of Cologne, Research Center Karlsruhe, German Weather Service) formed a network developing a model system for chemistry transport calculations on different scales. The network was optimized, based on each module and combined for the different interfaces in order to perform daily preoperational ozone forecasts and its precursors at the German Weather Service in summer 1999 (May through September). The setup of the model system, the interfaces and changes of each module are described. The results of the whole preoperational episode are displayed and discussed. Main efforts were done analyzing the model climate statistics and the verification of the predictions with an extensive data base of observations at stations in Germany. The results of this extensive verification demonstrate the relatively good performance of the entire forecast system.  相似文献   
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