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Agriculture and forest rodent problems and control in Italy
Rodent pest problems and their control in Italy are reviewed. Two rats, Rattus norvegicus and Rattus rattus, and the field mouse, Apodemus sylvaticus, are often important pests both in rural and forestry areas. Other species, such as voles, Microtus arvalis and Microtus (Pitymys) savii, in orchards and in horticulture, and Sciurus vulgaris and Myoxus (Glis) glis in forestry, sometimes represent serious problems. For each species the kind of damage and control is recorded, and additional considerations are supplied to the public and private organizations responsible for rodent control
On the remarkable relations among PDEs integrable by the inverse spectral transform method, by the method of characteristics and by the Hopf-Cole transformation
We establish deep and remarkable connections among partial differential
equations (PDEs) integrable by different methods: the inverse spectral
transform method, the method of characteristics and the Hopf-Cole
transformation. More concretely, 1) we show that the integrability properties
(Lax pair, infinitely-many commuting symmetries, large classes of analytic
solutions) of (2+1)-dimensional PDEs integrable by the Inverse Scattering
Transform method (-integrable) can be generated by the integrability
properties of the (1+1)-dimensional matrix B\"urgers hierarchy, integrable by
the matrix Hopf-Cole transformation (-integrable). 2) We show that the
integrability properties i) of -integrable PDEs in (1+1)-dimensions, ii) of
the multidimensional generalizations of the GL(M,\CC) self-dual Yang Mills
equations, and iii) of the multidimensional Calogero equations can be generated
by the integrability properties of a recently introduced multidimensional
matrix equation solvable by the method of characteristics. To establish the
above links, we consider a block Frobenius matrix reduction of the relevant
matrix fields, leading to integrable chains of matrix equations for the blocks
of such a Frobenius matrix, followed by a systematic elimination procedure of
some of these blocks. The construction of large classes of solutions of the
soliton equations from solutions of the matrix B\"urgers hierarchy turns out to
be intimately related to the construction of solutions in Sato theory. 3) We
finally show that suitable generalizations of the block Frobenius matrix
reduction of the matrix B\"urgers hierarchy generates PDEs exhibiting
integrability properties in common with both - and - integrable
equations.Comment: 30 page
Initial-Boundary Value Problems for Linear and Soliton PDEs
Evolution PDEs for dispersive waves are considered in both linear and
nonlinear integrable cases, and initial-boundary value problems associated with
them are formulated in spectral space. A method of solution is presented, which
is based on the elimination of the unknown boundary values by proper
restrictions of the functional space and of the spectral variable complex
domain. Illustrative examples include the linear Schroedinger equation on
compact and semicompact n-dimensional domains and the nonlinear Schroedinger
equation on the semiline.Comment: 18 pages, LATEX, submitted to the proccedings of NEEDS 2001 - Special
Issue, to be published in the Journal of Theoretical and Mathematical Physic
Dilepton production at HADES: theoretical predictions
Dileptons represent a unique probe for nuclear matter under extreme
conditions reached in heavy-ion collisions. They allow to study meson
properties, like mass and decay width, at various density and temperature
regimes. Present days models allow generally a good description of dilepton
spectra in ultra-relativistic heavy ion collision. For the energy regime of a
few GeV/nucleon, important discrepancies between theory and experiment, known
as the DLS puzzle, have been observed. Various models, including the one
developed by the T\"{u}bingen group, have tried to address this problem, but
have proven only partially successful. High precision spectra of dilepton
emission in heavy-ion reactions at 1 and 2 GeV/nucleon will be released in the
near future by the HADES Collaboration at GSI. Here we present the predictions
for dilepton spectra in C+C reactions at 1 and 2 GeV/nucleon and investigate up
to what degree possible scenarios for the in-medium modification of vector
mesons properties are accessible by the HADES experiment.Comment: 12 pages, 4 figures; submitted to Phys.Lett.
Low mass dimuons within a hybrid approach
We analyse dilepton emission from hot and dense hadronic matter using a
hybrid approach based on the Ultrarelativistic Quantum Molecular Dynamics
(UrQMD) transport model with an intermediate hydrodynamic stage for the
description of heavy-ion collisions at relativistic energies. Focusing on the
enhancement with respect to the contribution from long-lived hadron decays
after freeze-out observed at the SPS in the low mass region of the dilepton
spectra (often referred to as "the excess"), the relative importance of the
emission from the equilibrium and the non-equilibrium stages is discussed.Comment: Proceedings of Hot Quarks 2010, 21-26 June 2010 Las Londe Les Maures;
v2: Corrected typos and added a commen
Many-body models for molecular nanomagnets
We present a flexible and effective ab-initio scheme to build many-body
models for molecular nanomagnets, and to calculate magnetic exchange couplings
and zero-field splittings. It is based on using localized Foster-Boys orbitals
as one-electron basis. We apply this scheme to three paradigmatic systems, the
antiferromagnetic rings Cr8 and Cr7Ni and the single molecule magnet Fe4. In
all cases we identify the essential magnetic interactions and find excellent
agreement with experiments.Comment: 5 pages, 3 figure
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