997 resultados para 7140-205


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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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Taxonomic revision of ergots and related fungi in Australia.

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Contenido: La encíclica Fides et ratio de Juan Pablo II / La Dirección – Die Gegenwart del Themis bei Parmenides un der entzug der bestimmung im Heideggers Lichtung / Stefan Winter – El tiempo como medida de la primera esfera en la Física de Aristóteles / Marcelo L. Imperiale – St. Albert the Great and St. Thomas Aquinas on the presence of elements in compounds / Steven Baldner – Santo Tomás de Aquino, psicólogo / Ignacio Andereggen – Aquinas on creation and the metaphysical foundation of science / William E. Carroll – Las fuentes jurídicas romanas en Santo Tomás de Aquino / Alfredo Gustavo Di Pietro – La causalidad humana en la filosofía de la historia de Giambattista Vico / Juan Francisco Franck – Questions disputées de la politique chrétienne de Jacques Maritain / Yves Floucat – Die tektonik des submodernen Denkens im Schein ihrer Kunst / Heribert Boeder – El concepto de tolerancia / Alejandro G. Vigo – Modern science and time: an evaluation / Leo J. Elders – Tecnociencia y crisis ambiental / Héctor J. Padrón – The importante of order in theological discusión / Timothy L. Smith – La metafísica a pesar de Heidegger / Mario Enrique Sacchi – Notas y comentarios – Bibliografía

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Grupo dos 32 (Trinta e dois) reúne-se para estudar os pontos críticos do substitutivo apresentado pelo Relator Bernardo Cabral, em busca de entendimento com o Grupo do Consenso em relação a temas como a reforma agrária, a anistia e sistema tributário. O Grupo dos 32 examinou também o capítulo sobre a administração pública. A Deputada Sandra Cavalcante (PFL-RJ) informa que a administração pública necessita de regras mais rígidas, de forma a acabar com o clientelismo dentro do Estado. Para o PMDB o substitutivo do relator, Deputado Bernardo Cabral (PMDB-AM), tem avanços importantes, mas há pontos que precisam refletir melhor as posições defendidas pelo partido. O Líder do PMDB, Deputado Mário Covas, considera que, tanto quanto possível, a Constituição será objeto de negociação, mas há certos temas que terão que ser decididos pelo voto no Plenário da Assembleia Nacional Constituinte (ANC). Um dos pontos que o PMDB quer mudar é a Reforma Agrária. Para José Eduardo Raduan, Presidente do Instituto Nacional de Colonização e Reforma Agrária (INCRA), é inviável a Reforma Agrária com imissão de posse após 90 dias da desapropriação. Projeto de Constituição não torna obrigatório o diploma de jornalismo para ser jornalista. O Deputado Carlos Alberto Oliveira (PDT-RJ) considera que é desastroso para o exercício de cidadania, porque a profissão de jornalista é tão especializada como tantas outras. A Deputada Cristina Tavares (PMDB-PE) declara que se trata de um dos mais graves retrocessos. Estudantes e professores de comunicação também são contra o fim da exigência de diploma. O professor de comunicação da UNB Wladimir de Carvalho declara que o caso parece ser resultado de um lobby da grande imprensa. Já o também professor de comunicação da UNB Murilo Ramos informa que o objetivo é abrir o mercado de mão-de-obra, para aumentar o lucro dos empresários. O Deputado Antônio Brito (PMDB-RS) afirma que a luta não é só dos jornalistas e sua situação profissional, mas que há preocupação com o país e com a qualidade da informação que os brasileiros receberão.

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本文研究了外水相pH值、流动载体浓度、表面活性剂浓度、内相解析酸浓度、水乳比、油内比等因素对二(2,4,4-三甲基戊基)单硫代膦酸(Cyanex302)-上胺205-正庚烷乳状液 膜迁移Sc(Ⅲ)的影响。在一定条件下,Sc(Ⅲ)可以快速而完全地迁移,有可能实现Sc(Ⅲ)与Fe(Ⅲ)、Lu(Ⅲ)的分离。

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本文研究了异丙基膦酸单(1-己基-4-乙基)辛酯(简称PT-2)上胺205-正庚烷乳状液膜分离钪(Ⅲ),铁(Ⅲ),镥(Ⅲ)及外相酸度、表面活性剂浓度、流动载体浓度和内相酸度对Sc(Ⅲ)、Fe(Ⅲ)、Lu(Ⅲ)迁移影响。实验结果表明,在一定的条件下Sc(Ⅲ)有可能实现与Fe(Ⅲ)、Lu(Ⅲ)的分离。

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本文研究了二(2,4,4-三甲基戊基)膦酸(Cyanex272)-上胺205-正庚烷乳状液膜分离Sc(Ⅲ)、Fe(Ⅲ)和Lu(Ⅲ)。考察了外相酸度、表面活性剂浓度、流动载体浓度及内相盐酸浓度对Sc(Ⅲ)迁移的影响。并探讨了该液膜体系分离Sc(Ⅲ)、Fe(Ⅲ)和Lu(Ⅲ)的可能性,结果表明,该体系对于稀土矿中Sc(Ⅲ)的分离与分析有良好的应用前景。

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Incorporation of Ags by dendritic cells (DCs) increases when Ags are targeted to endocytic receptors by mAbs. We have previously demonstrated in the mouse that mAbs against C-type lectins administered intradermally are taken up by epidermal Langerhans cells (LCs), dermal Langerin(neg) DCs, and dermal Langerin(+) DCs in situ. However, the relative contribution of these skin DC subsets to the induction of immune responses after Ag targeting has not been addressed in vivo. We show in this study that murine epidermal LCs and dermal DCs transport intradermally injected mAbs against the lectin receptor DEC-205/CD205 in vivo. Skin DCs targeted in situ with mAbs migrated through lymphatic vessels in steady state and inflammation. In the skin-draining lymph nodes, targeting mAbs were found in resident CD8a(+) DCs and in migrating skin DCs. More than 70% of targeted DCs expressed Langerin, including dermal Langerin(+) DCs and LCs. Numbers of targeted skin DCs in the nodes increased 2-3-fold when skin was topically inflamed by the TLR7 agonist imiquimod. Complete removal of the site where OVA-coupled anti-DEC-205 had been injected decreased endogenous cytotoxic responses against OVA peptide-loaded target cells by 40-50%. Surprisingly, selective ablation of all Langerin(+) skin DCs in Langerin-DTR knock-in mice did not affect such responses independently of the adjuvant chosen. Thus, in cutaneous immunization strategies where Ag is targeted to DCs, Langerin(+) skin DCs play a major role in transport of anti-DEC-205 mAb, although Langerin(neg) dermal DCs and CD8a(+) DCs are sufficient to subsequent CD8(+) T cell responses.