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Glucose-sulfate conjugates as a new phase II metabolite formed by aquatic crustaceans
ArticleBIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS. 360(2): 490-495 (2007)journal articl
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A Discussion of Studies in CDST: An Introduction
In this special issue on Complex Dynamic Systems Theory (CDST), four empirical studies (by Ahmed, Choe, Ciriani Dean, and Van Horn) investigate interlanguage through a CDST perspective. As a way of extending the discussion on CDST, students in the Second Language Acquisition (SLA) doctoral seminar in the Applied Linguistics and TESOL Program at Teachers College, Columbia University were asked to select and discuss one empirical study published in the current issue, reflecting on the following: the theoretical viewpoint, the findings, the methodology, and/or the significance and implications. In response, three papers were submitted to the present forum
Homotopy Structure of 5d Vacua
It is shown that flat zero-energy solutions (vacua) of the 5d Kaluza-Klein
theory admit a non-trivial homotopy structure generated by certain Kaluza-Klein
excitations. These vacua consist of an infinite set of homotopically different
spacetimes denoted by , among which
and are especially identified as and
, the ground states of the 5d Kaluza-Klein theory and the 5d general
relativity, respectively (where represents the -dimensional Minkowski
space).Comment: 8 page
A Fractional Fokker-Planck Model for Anomalous Diffusion
In this paper we present a study of anomalous diffusion using a Fokker-Planck
description with fractional velocity derivatives. The distribution functions
are found using numerical means for varying degree of fractionality observing
the transition from a Gaussian distribution to a L\'evy distribution. The
statistical properties of the distribution functions are assessed by a
generalized expectation measure and entropy in terms of Tsallis statistical
mechanics. We find that the ratio of the generalized entropy and expectation is
increasing with decreasing fractionality towards the well known so-called
sub-diffusive domain, indicating a self-organising behavior.Comment: 22 pages, 14 figure
Estimation of sources and inflow of dioxins and polycyclic aromatic hydrocarbons from the sediment core of Lake Suwa, Japan
ArticleEnviromental Pollution. 138(3): 529-537 (2005)journal articl
Comparison of crystal structures and effects of Co substitution in a new member of Fe-1111 superconductor family AeFeAsF(Ae = Ca and Sr): a possible candidate for higher Tc superconductor
We refined crystal structures of newly found members of the Fe-1111
superconductor family, CaFe\_{1-x}Co\_{x}AsF and SrFe\_{1-x}Co\_{x}AsF (x = 0,
0.06, 0.12) by powder synchrotron X-ray diffraction analysis. The tetragonal to
orthorhombic phase transitions were observed at ~120 K for unsubstituted
CaFeAsF and at ~180 K for unsubstituted SrFeAsF, the transition temperatures
agreeing with kinks observed in temperature-dependent resistivity curves.
Although the transition temperature decreases, the structural phase transitions
were observed below 100 K in both samples of x = 0.06, and finally they were
suppressed in the doping level of x = 0.12. The refined structures reveal that
distortions of the FeAs4 tetrahedron from the regular tetrahedron likely
originate from mismatches in atomic radii among the constituent elements. In
this system, the enlarged FeAs4 tetrahedron resulting from larger radius of Sr
than that of Ca is flattened along a-b plane, whereas the smaller radius of Ca
makes the tetrahedron closer to regular one, and their characteristic shapes
are further enhanced by Co substitution. These results suggest that the CaFeAsF
compound is a promising candidate for higher-Tc superconductor.Comment: 17 pages, 8 figures, 2 tables, Supplementary information is included
at the end of the documen
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