2,499 research outputs found
Demographic responses to the chemical control of Doublegee
Control of Doublegee in medic pasture, 88WH47. Competitive effect and response of Emex australis in a grazed animal pasture
Long-time Behavior of a Two-layer Model of Baroclinic Quasi-geostrophic Turbulence
We study a viscous two-layer quasi-geostrophic beta-plane model that is
forced by imposition of a spatially uniform vertical shear in the eastward
(zonal) component of the layer flows, or equivalently a spatially uniform
north-south temperature gradient. We prove that the model is linearly unstable,
but that non-linear solutions are bounded in time by a bound which is
independent of the initial data and is determined only by the physical
parameters of the model. We further prove, using arguments first presented in
the study of the Kuramoto-Sivashinsky equation, the existence of an absorbing
ball in appropriate function spaces, and in fact the existence of a compact
finite-dimensional attractor, and provide upper bounds for the fractal and
Hausdorff dimensions of the attractor. Finally, we show the existence of an
inertial manifold for the dynamical system generated by the model's solution
operator. Our results provide rigorous justification for observations made by
Panetta based on long-time numerical integrations of the model equations
Il rischio di liquiditĂ : regolamentazione e best practice
In the light of the recent financial market turmoil, this paper focuses on liquidity risk management from the point of view of both supervisory authorities and large financial institutions. This research aims at pointing out the main differences between national regulations and supervisory regimes in the most important EU Countries (UK, DE, IT, FR, SP), trying to explain the rationale and the limits of the different approaches. Taking into account liquidity risk management models adopted in the major banking groups within the same countries, this paper also suggests the most significant issues to be considered in order to implement effective liquidity risk management. Areas of convergence/divergence at international level are highlighted and “food for thought” is offered on a subject that is gaining more and more attention of academics and officials worldwide, that is to say the importance of finding regulatory solutions and management models suited to 'remove' systemic crisis
Il rischio di liquiditĂ : regolamentazione e best practice
In the light of the recent financial market turmoil, this paper focuses on liquidity risk management from the point of view of both supervisory authorities and large financial institutions. This research aims at pointing out the main differences between national regulations and supervisory regimes in the most important EU Countries (UK, DE, IT, FR, SP), trying to explain the rationale and the limits of the different approaches. Taking into account liquidity risk management models adopted in the major banking groups within the same countries, this paper also suggests the most significant issues to be considered in order to implement effective liquidity risk management. Areas of convergence/divergence at international level are highlighted and “food for thought” is offered on a subject that is gaining more and more attention of academics and officials worldwide, that is to say the importance of finding regulatory solutions and management models suited to 'remove' systemic crisis
Coupling Microstructure Outputs of Process Models to Ultrasonic Inspectability Predictions
The efforts of the materials community can be characterized as the study of the relationship of processing, structure, properties and performance, as schematically illustrated in Figure 1. Added, in parentheses, are quantities of importance when these ideas are applied to ultrasonic NDE. It would be highly desirable if one could start from models of processes such as rolling, casting and extrusion; predict the microstructural features produced, such as grain size or shape, texture (preferred grain orientation), or the two-point correlation of elastic constants (to be discussed later); predict the resulting ultrasonic properties such as velocity v, attenuation a and backscattering coefficient η; and ultimately determine the inspectability of the part. Such a capability would allow NDE to be considered explicitly during the selection of material processing procedures
Dispersive stabilization of the inverse cascade for the Kolmogorov flow
It is shown by perturbation techniques and numerical simulations that the
inverse cascade of kink-antikink annihilations, characteristic of the
Kolmogorov flow in the slightly supercritical Reynolds number regime, is halted
by the dispersive action of Rossby waves in the beta-plane approximation. For
beta tending to zero, the largest excited scale is proportional to the
logarithm of one over beta and differs strongly from what is predicted by
standard dimensional phenomenology which ignores depletion of nonlinearity.Comment: 4 pages, LATEX, 3 figures. v3: revised version with minor correction
Absence of FGFR3–TACC3 rearrangement in hematological malignancies with numerical chromosomal alteration
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3D enamel thickness in Neandertal and modern human permanent canines
Enamel thickness figures prominently in studies of human evolution, particularly for taxonomy, phylogeny, and paleodietary reconstruction. Attention has focused on molar teeth, through the use of advanced imaging technologies and novel protocols. Despite the important results achieved thus far, further work is needed to investigate all tooth classes. We apply a recent approach developed for anterior teeth to investigate the 3D enamel thickness of Neandertal and modern human (MH) canines. In terms of crown size, the values obtained for both upper and lower unworn/slightly worn canines are significantly greater in Neandertals than in Upper Paleolithic and recent MH. The 3D relative enamel thickness (RET) is significantly lower in Neandertals than in MH. Moreover, differences in 3D RET values between the two groups appear to decrease in worn canines beginning from wear stage 3, suggesting that both the pattern and the stage of wear may have important effects on the 3D RET value. Nevertheless, the 3D average enamel thickness (AET) does not differ between the two groups. In both groups, 3D AET and 3D RET indices are greater in upper canines than in lower canines, and overall the enamel is thicker on the occlusal half of the labial aspect of the crown, particularly in MH. By contrast, the few early modern humans investigated show the highest volumes of enamel while for all other components of 3D enamel, thickness this group holds an intermediate position between Neandertals and recent MH. Overall, our study supports the general findings that Neandertals have relatively thinner enamel than MH (as also observed in molars), indicating that unworn/slightly worn canines can be successfully used to discriminate between the two groups. Further studies, however, are needed to understand whether these differences are functionally related or are the result of pleiotropic or genetic drift effects
Effect of lifestyle factors on Staphylococcus aureus gut colonization in Swedish and Italian infants
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