12 research outputs found
The tactics of surgical treatment in metastatic lesions of upper cervical spine.
We demonstrated a successful case of surgical treatment of the patient with metastatic lesion of upper cervical spine with respect to multidisciplinary approach. We performed simultaneous two-stage surgical intervention, the first stage being occipitospondylodesis by multi-segment construction; and second —tumor resection from expanded combined access. It has been stated that the proposed surgical tactics allows performing curative resection in one surgical session without neurological deficit buildup in the postoperative period.</p
Exact conserved quantities on the cylinder I: conformal case
The nonlinear integral equations describing the spectra of the left and right
(continuous) quantum KdV equations on the cylinder are derived from integrable
lattice field theories, which turn out to allow the Bethe Ansatz equations of a
twisted ``spin -1/2'' chain. A very useful mapping to the more common nonlinear
integral equation of the twisted continuous spin chain is found. The
diagonalization of the transfer matrix is performed. The vacua sector is
analysed in detail detecting the primary states of the minimal conformal models
and giving integral expressions for the eigenvalues of the transfer matrix.
Contact with the seminal papers \cite{BLZ, BLZ2} by Bazhanov, Lukyanov and
Zamolodchikov is realised. General expressions for the eigenvalues of the
infinite-dimensional abelian algebra of local integrals of motion are given and
explicitly calculated at the free fermion point.Comment: Journal version: references added and minor corrections performe
A Monoidal Category for Perturbed Defects in Conformal Field Theory
Starting from an abelian rigid braided monoidal category C we define an
abelian rigid monoidal category C_F which captures some aspects of perturbed
conformal defects in two-dimensional conformal field theory. Namely, for V a
rational vertex operator algebra we consider the charge-conjugation CFT
constructed from V (the Cardy case). Then C = Rep(V) and an object in C_F
corresponds to a conformal defect condition together with a direction of
perturbation. We assign to each object in C_F an operator on the space of
states of the CFT, the perturbed defect operator, and show that the assignment
factors through the Grothendieck ring of C_F. This allows one to find
functional relations between perturbed defect operators. Such relations are
interesting because they contain information about the integrable structure of
the CFT.Comment: 38 pages; v2: corrected typos and expanded section 3.2, version to
appear in CM
On the origin of the giant magnetic moment of the Al-Mn quasicrystals
Ab initio calculations of magnetic moments for icosahedral clusters contained in crystal structures Al10Mn3, Al5Co2, Al17Mn4 (Al13Cr4Si4-type) fulfilled in the framework of Density Functional Theory. The AlMn cluster having the trigonal D3h symmetry with the triangle of Mn ions in the interior has the moment being equal to three magnetic moments of a single manganese ion (4.4 μB), the moment of the tetrahedral Td cluster with the Mn tetrahedron in the interior is equal approximately to twelve magnetic moments of the single manganese ion (15.5 μB). The magnetic moment of icosahedral Al-Co clusters having the same configuration is equal to zero. The magnetic moments of the rod assembled from the icosahedral clusters with the sequence Td D3h - Td was found to be 20.5 μB. This value permits to explain the giant magnetic moment of icosahedral and decagonal Al-Mn quasicrystals and gives the indirect evidence to the hierarchical model of the quasicrystals structure proposed by the authors recently. An arrangement of magnetic moment carriers in the interior of the aluminum shell of icosahedral clusters permits to suggest the interaction between contacting manganese ions as the main origin of the giant magnetic moment of the Al-Mn quasicrystals