2,787 research outputs found
Zu einer Fundamentalreform der deutschen Einkommensteuer: die Einfachsteuer des Heidelberger Kreises
Die mehr oder weniger zaghaften Reformversuche bei der Einkommen- und Körperschaftsteuer haben nicht zu einer grundlegenden Stärkung der Wachstumsdynamik in Deutschland geführt. Auch wenn die Reformschritte 2004 und 2005 noch ausstehen, sind diese bereits in den Erwartungsbildungen antizipiert, so dass unser Land auch weiterhin auf den hinteren Rängen der vielen internationalen Effizienzvergleiche positioniert sein wird. Nur eine Fundamentalreform bei der Einkommens- und Gewinnbesteuerung, die insbesondere mit wesentlichen Vereinfachungen in der Steuersystematik verbunden ist, kann die notwendigen steuerlichen Impulse setzen, um neue Wachstumskräfte zu wecken. Dabei hat der Heidelberger Steuerkreis immer betont, dass eine grundlegende Steuerreform auch sozial- und arbeitsmarktpolitisch unterfüttert werden muss
Effects of grain shape on packing and dilatancy of sheared granular materials
Granular material exposed to shear shows a variety of unique phenomena:
Reynolds dilatancy, positional order and orientational order effects may
compete in the shear zone. We study granular packings consisting of macroscopic
prolate, oblate and spherical grains and compare their behaviour. X-ray
tomography is used to determine the particle positions and orientations in a
cylindrical split bottom shear cell. Packing densities and the arrangements of
individual particles in the shear zone are evaluated. For anisometric
particles, we observe the competition of two opposite effects. One the one
hand, the sheared granulate is dilated, but on the other hand the particles
reorient and align with respect to the streamlines. Even though aligned
cylinders in principle may achieve higher packing densities, this alignment
compensates for the effect of dilatancy only partially. The complex
rearrangements lead to a depression of the surface above the well oriented
region while neigbouring parts still show the effect of dilation in the form of
heaps. For grains with isotropic shapes, the surface remains rather flat.
Perfect monodisperse spheres crystallize in the shear zone, whereby positional
order partially overcompensates dilatancy effects. However, already slight
deviations from the ideal monodisperse sphere shape inhibit crystallization.Comment: 12 pages, 13 figures, accepted in Soft Matte
Минералого-петрохимические и геохимические черты околорудного метасоматизма в Западном золоторудном месторождении (Северное Забайкалье)
Приведены данные об условиях залегания, морфологии рудных тел, минеральном составе, физико-химических и термодинамических режимах образования руд Западного золоторудного месторождения Северного Забайкалья. Впервые показаны порядок минеральной зональности (структура) и минералого-петрохимические черты аподолеритовых околожильных метасоматических ореолов. Доказывается принадлежность последних к березитовой метасоматической формации, а месторождения - к золотой субформации золото-уран-полиметаллической березитовой рудной формации. Слабо контрастные аномалии золота, серебра, ртути приурочены к тыловым зонам околожильных метасоматических ореолов в непосредственном обрамлении слабозолотоносных (первые г/т) интервалов кварцевых жил. Аргументируются генетические связи околожильных метасоматических и геохимических ореолов с рудами и образование их в рудообразующем процессе позднепалеозойской металлогенической эпохи. Основные минералого-петрохимические и геохимические черты околожильного метасоматизма рассмотрены в сравнении с таковыми других месторождений Северо-Забайкальского золоторудного района
Evolution of shear zones in granular materials
The evolution of wide shear zones (or shear bands) was investigated
experimentally and numerically for quasistatic dry granular flows in split
bottom shear cells. We compare the behavior of materials consisting of beads,
irregular grains (e.g. sand) and elongated particles. Shearing an initially
random sample, the zone width was found to significantly decrease in the first
stage of the process. The characteristic shear strain associated with this
decrease is about unity and it is systematically increasing with shape
anisotropy, i.e. when the grain shape changes from spherical to irregular (e.g.
sand) and becomes elongated (pegs). The strongly decreasing tendency of the
zone width is followed by a slight increase which is more pronounced for rod
like particles than for grains with smaller shape anisotropy (beads or
irregular particles). The evolution of the zone width is connected to shear
induced density change and for nonspherical particles it also involves grain
reorientation effects. The final zone width is significantly smaller for
irregular grains than for spherical beads.Comment: 11 pages, 12 figures, submitted to Phys. Rev.
Expression of Human Immunodeficiency Virus Type 1 Gag Protein Precursor and Envelope Proteins from a Vesicular Stomatitis Virus Recombinant: High-Level Production of Virus-like Particles Containing HIV Envelope
AbstractRecombinant vesicular stomatitis viruses have been developed as high-level expression vectors which serve as effective vaccine vectors in animals (Roberts et al., 1998, J. Virol. 72, 4704–4711; Roberts et al., 1999, J. Virol. 73, 3723–3732). Here we show that two genes can be expressed simultaneously from a single, live-attenuated VSV recombinant. The genes used encode the Pr55gag protein precursor of HIV-1 (1.7-kb gene) and an HIV-1 envelope (Env) protein (2.4 kb gene). Our results show that VSV can accommodate up to a 40% increase in genome size with only a threefold reduction in virus titer. Recombinants expressing the Pr55gag protein precursor with or without Env protein produced abundant HIV virus-like particles (VLPs) in addition to bullet-shaped VSV particles. HIV Env protein expressed from a VSV recombinant also expressing Gag was specifically incorporated into the HIV VLPs but not into the VSV particles. In contrast, VSV G protein was found in both VSV particles and in HIV VLPs. Such VSV/HIV recombinants producing HIV VLPs with Env protein could be an effective source of HIV-like particles inducing both cellular and antibody-mediated immunity to HIV-1
The Metropolis and Evangelical Life: Coherence and Fragmentation in the ‘Lost City of London’
This article examines the interplay of different processes of cultural and subjective fragmentation experienced by conservative evangelical Anglicans, based on an ethnographic study of a congregation in central London. The author focuses on the evangelistic speaking practices of members of this church to explore how individuals negotiate contradictory norms of interaction as they move through different city spaces, and considers their response to tensions created by the demands of their workplace and their religious lives. Drawing on Georg Simmel’s ‘The Metropolis and Mental Life’, the author argues that their faith provides a sense of coherence and unity that responds to experiences of cultural fragmentation characteristic of everyday life in the city, while simultaneously leading to a specific consciousness of moral fragmentation that is inherent to conservative evangelicalism
Untersuchung der Praxistauglichkeit eines Ortungssystems zur Verbesserung des Herdenmanagements eines Milchviehbetriebes
Ziel dieses Versuches, der im Rahmen eines Praxisprojektes durchgeführt wurde, war die Überprüfung der Praxistauglichkeit des Real Time Location Systems (RTLS) Ubisense 7000 für das Herdenmanagement. Neben der Überprüfung der Genauigkeit der mit dem Ortungssystems erhobenen Daten, wurden Daten, zur Aktivitätsmessung, Brunsterkennung, Aufenthaltsdauer in den Funktionsbereichen sowie Laufverhalten mithilfe von Pedometern und Videobeobachtung erfasst
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