2,473 research outputs found
Post-Dissolution Liabilities of Shareholders and Directors for Claims Against Dissolved Corporations
This Article initially will explore the nature and extent of shareholders\u27 and directors\u27 liabilities for contingent claims against the dissolved corporation by examining section 105 of the Model Business Corporation Act and the case law of those states that have adopted the Model Act.\u27 Two purposes underlying the Model Act are uniformity and progressive resolution of issues inadequately resolved by the common law or earlier statutes. An exhaustive analysis of the case law under section 105 of the Model Act, however,reveals that both purposes have been frustrated, if not defeated. First, uniformity among jurisdictions, as well as within each Model Act state, is defeated by the overwhelming inconsistency in the case law. Litigants presently can choose precedent to support almost any position they seek to argue. Moreover, section 105 itself does not resolve clearly any of the major post-dissolution liability issues. Its ambiguous language has furnished litigants and courts with little guidance in determining the legislatively intended answers to key issues
On the ill/well-posedness and nonlinear instability of the magneto-geostrophic equations
We consider an active scalar equation that is motivated by a model for
magneto-geostrophic dynamics and the geodynamo. We prove that the non-diffusive
equation is ill-posed in the sense of Hadamard in Sobolev spaces. In contrast,
the critically diffusive equation is well-posed. In this case we give an
example of a steady state that is nonlinearly unstable, and hence produces a
dynamo effect in the sense of an exponentially growing magnetic field.Comment: We have modified the definition of Lipschitz well-posedness, in order
to allow for a possible loss in regularity of the solution ma
Second-order gravitational self-force
We derive an expression for the second-order gravitational self-force that
acts on a self-gravitating compact-object moving in a curved background
spacetime. First we develop a new method of derivation and apply it to the
derivation of the first-order gravitational self-force. Here we find that our
result conforms with the previously derived expression. Next we generalize our
method and derive a new expression for the second-order gravitational
self-force. This study also has a practical motivation: The data analysis for
the planned gravitational wave detector LISA requires construction of waveforms
templates for the expected gravitational waves. Calculation of the two leading
orders of the gravitational self-force will enable one to construct highly
accurate waveform templates, which are needed for the data analysis of
gravitational-waves that are emitted from extreme mass-ratio binaries.Comment: 35 page
Emergence of fractal behavior in condensation-driven aggregation
We investigate a model in which an ensemble of chemically identical Brownian
particles are continuously growing by condensation and at the same time undergo
irreversible aggregation whenever two particles come into contact upon
collision. We solved the model exactly by using scaling theory for the case
whereby a particle, say of size , grows by an amount over the
time it takes to collide with another particle of any size. It is shown that
the particle size spectra of such system exhibit transition to dynamic scaling
accompanied by the emergence of fractal of
dimension . One of the remarkable feature of this
model is that it is governed by a non-trivial conservation law, namely, the
moment of is time invariant regardless of the choice of the
initial conditions. The reason why it remains conserved is explained by using a
simple dimensional analysis. We show that the scaling exponents and
are locked with the fractal dimension via a generalized scaling relation
.Comment: 8 pages, 6 figures, to appear in Phys. Rev.
Bone mass does not correlate with the serum fibroblast growth factor 23 in hemodialysis patients
Circulating fibroblast growth factor 23 (FGF23) increases renal phosphate excretion, decreases bone mineralization and is markedly increased in hemodialysis patients. Bone cells express fibroblast growth receptor 1, suggesting that FGF23 could alter bone mineralization by means of a direct effect on the skeleton and/or secondarily due to hypophosphatemia. To distinguish between these possibilities we measured serum concentrations of FGF23, parathyroid hormone, phosphate, calcium, and markers of bone remodeling, and assessed bone mineral density in 99 hemodialysis patients. FGF23 concentrations were increased in all hemodialysis patients, even in those without hyperphosphatemia, and positively correlated with serum phosphate but not with parathyroid hormone. Hemodialysis did not decrease the serum FGF23 concentration. We found no significant correlation between serum FGF23 levels and bone mineral density. Further analysis by gender or T-score did not modify these results. Serum markers of bone remodeling significantly correlated with parathyroid hormone but not with FGF23 levels. The increase in serum FGF23 concentration in hemodialysis patients cannot be solely ascribed to hyperphosphatemia. Our study suggests that the effects of FGF23 on bone mineralization are mainly due to hypophosphatemia and not a direct effect on bone
Conformal scattering for a nonlinear wave equation on a curved background
The purpose of this paper is to establish a geometric scattering result for a
conformally invariant nonlinear wave equation on an asymptotically simple
spacetime. The scattering operator is obtained via trace operators at null
infinities. The proof is achieved in three steps. A priori linear estimates are
obtained via an adaptation of the Morawetz vector field in the Schwarzschild
spacetime and a method used by H\"ormander for the Goursat problem. A
well-posedness result for the characteristic Cauchy problem on a light cone at
infinity is then obtained. This requires a control of the nonlinearity uniform
in time which comes from an estimates of the Sobolev constant and a decay
assumption on the nonlinearity of the equation. Finally, the trace operators on
conformal infinities are built and used to define the conformal scattering
operator
A family of diameter-based eigenvalue bounds for quantum graphs
We establish a sharp lower bound on the first non-trivial eigenvalue of the
Laplacian on a metric graph equipped with natural (i.e., continuity and
Kirchhoff) vertex conditions in terms of the diameter and the total length of
the graph. This extends a result of, and resolves an open problem from, [J. B.
Kennedy, P. Kurasov, G. Malenov\'a and D. Mugnolo, Ann. Henri Poincar\'e 17
(2016), 2439--2473, Section 7.2], and also complements an analogous lower bound
for the corresponding eigenvalue of the combinatorial Laplacian on a discrete
graph. We also give a family of corresponding lower bounds for the higher
eigenvalues under the assumption that the total length of the graph is
sufficiently large compared with its diameter. These inequalities are sharp in
the case of trees.Comment: Substantial revision of v1. The main result, originally for the first
eigenvalue, has been generalised to the higher ones. The title has been
changed and the proofs substantially reorganised to reflect the new result,
and a section containing concluding remarks has been adde
Support varieties for selfinjective algebras
Support varieties for any finite dimensional algebra over a field were
introduced by Snashall-Solberg using graded subalgebras of the Hochschild
cohomology. We mainly study these varieties for selfinjective algebras under
appropriate finite generation hypotheses. Then many of the standard results
from the theory of support varieties for finite groups generalize to this
situation. In particular, the complexity of the module equals the dimension of
its corresponding variety, all closed homogeneous varieties occur as the
variety of some module, the variety of an indecomposable module is connected,
periodic modules are lines and for symmetric algebras a generalization of
Webb's theorem is true
Influence of primary particle density in the morphology of agglomerates
Agglomeration processes occur in many different realms of science such as
colloid and aerosol formation or formation of bacterial colonies. We study the
influence of primary particle density in agglomerate structure using
diffusion-controlled Monte Carlo simulations with realistic space scales
through different regimes (DLA and DLCA). The equivalence of Monte Carlo time
steps to real time scales is given by Hirsch's hydrodynamical theory of
Brownian motion. Agglomerate behavior at different time stages of the
simulations suggests that three indices (fractal exponent, coordination number
and eccentricity index) characterize agglomerate geometry. Using these indices,
we have found that the initial density of primary particles greatly influences
the final structure of the agglomerate as observed in recent experimental
works.Comment: 11 pages, 13 figures, PRE, to appea
Johnson-Kendall-Roberts theory applied to living cells
Johnson-Kendall-Roberts (JKR) theory is an accurate model for strong adhesion
energies of soft slightly deformable material. Little is known about the
validity of this theory on complex systems such as living cells. We have
addressed this problem using a depletion controlled cell adhesion and measured
the force necessary to separate the cells with a micropipette technique. We
show that the cytoskeleton can provide the cells with a 3D structure that is
sufficiently elastic and has a sufficiently low deformability for JKR theory to
be valid. When the cytoskeleton is disrupted, JKR theory is no longer
applicable
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