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Some properties on -evaluation and its applications to -martingale decomposition
In this article, a sublinear expectation induced by -expectation is
introduced, which is called -evaluation for convenience. As an application,
we prove that any with some the
decomposition theorem holds and any integrable symmetric
-martingale can be represented as an It integral w.r.t
-Brownian motion. As a byproduct, we prove a regular property for
-martingale: Any -martingale has a quasi-continuous versionComment: 22 page
Probing the Low Mass Stellar End of the eta Chamaeleontis Cluster
We have identified three faint new members of the eta Chamaeleontis cluster.
Spectral types of the new members are estimated to be ~M5 based on their TiO
band strengths and broadband colors. With an age of 5-8 Myr for the cluster,
masses of these new members are estimated to be ~0.08 Msun. All three display
strong Li 6708A absorption and Halpha emission features including one with
Halpha emission equivalent width ~60A along with HeI 6678 & 7605 A emission
features that are characteristics of classical T Tauri stars.Comment: 11 pages, 4 figures, 2 tables, accepted in Ap
THEORETICAL STUDIES OF BILIPROTEIN CHROMOPHORES AND RELATED BILE PIGMENTS BY MOLECULAR ORBITAL AND RAMACHANDRAN TYPE CALCULATIONS
Ramachandran calculations have been used to gain insight into steric hindrance in bile
pigments related to biliprotein chromophores. The high optical activity of denatured phycocyanin, as
compared to phycoerythrin, has been related to the asymmetric substitution at ring A, which shifts the
equilibrium towards the P-helical form of the chromophore. Geometric effects on the electronic structures
and transitions have then been studied by molecular orbital calculations for several conjugation
systems including the chromophores of phycocyanin. phytochrome P,, cations, cation radicals and
tautomeric forms. For these different chromophores some general trends can be deduced. For instance,
for a given change in the gross shape (e.g. either unfolding of the molecule from a cyclic-helical to a fully
extended geometry, or upon out-of-plane twists of the pyrrole ring A) of the molecules under study, the
predicted absorption spectra all change in a simikar way. Nonetheless, there are characteristic distinctions
between the different n-systems, both in the transition energies and the charge distribution, which
can be related to their known differences in spectroscopic properties and their reactivity
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