1,721,338 research outputs found
On the reductions and classical solutions of the Schlesinger equations
Full text linkThe Schlesinger equations S(n,m) describe monodromy preserving deformations of order m Fuchsian systems with n+1 poles. They can be considered as a family of commuting time-dependent Hamiltonian systems on the direct product of n copies of m×m matrix algebras equipped with the standard linear Poisson bracket. In this paper we address the problem of reduction of particular solutions of “more complicated” Schlesinger equations S(n,m) to “simpler” S(n′,m′) having n′ < n or m′ < m
Direct processes for the systems Be-7,B-8 +Pb-208 at Coulomb barrier energies
Full text linkThe elastic scattering process for the nuclear reactions induced by the Radioactive Ion Beams Be-7 and B-8 on a Pb-208 target was measured for the first time in the energy range around the Coulomb barrier. Extensive theoretical calculations within the framework of the optical model were performed. An excellent agreement between experimental data and theoretical predictions was achieved for the reaction Be-7 + Pb-208 while a comprehensive understanding of the reaction dynamics induced by the more exotic projectile B-8 is still far to be reached. Predictions of the cross section for the breakup for both systems will also be given
RIB production and related experiments at EXOTIC
Full text linkRadioactive nuclei have a very deep relevance in many astrophysical scenarios, from the Big Bang nucleo-synthesis to supernova explosions. Several Nuclear Physics laboratories around the world have been constructing large-scale facilities for the production of Radioactive Ion Beams (RIBs). The main production techniques, i.e. In-Flight and Isotope Separation On Line, which will be reviewed in this contribution. In particular, we will concentrate on the production of light weakly-bound RIBs at the facility EXOTIC, located at INFN-LNL (Italy) and we will describe the most recent experiments
Neonato con circolo venoso superficiale addominale: alla ricerca di una diagnosi.
No full textNanoro, Burkina Faso. Caso clinico di un neonato di 10 giorni inviato da un centro infermieristico territoriale per "infiammazione" alla coscia e al testicolo destro. Anamnesi difficoltosa. Difficoltà di arrivare ad una diagnosi.
Esperienza che dimostra la grande importanza che riveste la clinica, unico mezzi a cui ci si può affidare in assenza di esami specialistici
Una "troppo breve" storia di convulsioni neonatali.
No full textQuesto caso clinico dimostra l'importaza di una buona raccolta anamnestica. la presentazione atipica delle clonie con la scarsa disponibilità dei mezzi diagnostici hanno reso difficile la diagnosi differenziale. Senza il dato della puntata febbrile del 13° giorno sarebbe stato impossibile pensare ad un esito di una meningite
Monodromy of certain Painlevé-VI transcendents and reflection groups
Full text linkWe study the global analytic properties of the solutions of a particular family of Painlevé VI equations with the parameters #=%=0, '=]] and 2!=(27-1)2 with arbitrary 7, 27p]Ê. We introduce a class of solutions having critical behaviour of algebraic type, and completely compute the structure of the analytic continuation of these solutions in terms of an auxiliary reflection group in the three dimensional space. The analytic continuation is given in terms of an action of the braid group on the triples of generators of the reflection group. We show that the finite orbits of this action correspond to the algebraic solutions of our Painlevé VI equation and use this result to classify all of them. We prove that the algebraic solutions of our Painlevé VI equation are in one-to-one correspondence with the regular polyhedra or star-polyhedra in the three dimensional space
Canonical structure and symmetries of the Schlesinger equations
No full textThe Schlesinger equations S (n,m) describe monodromy preserving deformations of order m Fuchsian systems with n + 1 poles. They can be considered as a family of commuting time-dependent Hamiltonian systems on the direct product of n copies of m× m matrix algebras equipped with the standard linear Poisson bracket. In this paper we present a new canonical Hamiltonian formulation of the general Schlesinger equations S (n,m) for all n, m and we compute the action of the symmetries of the Schlesinger equations in these coordinates. © Springer-Verlag 2007
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Le fasi redazionali e le concezioni della storia nelle Decadi di Biondo. Tra storia particolare e generale, tra antica e moderna Roma
No full textBlondus Flavius spent his entire life in the composition of the Historiae ab inclinatione Romanorum imperii, or Decades. Their compilation was long, and not always linear was their conception: we can find indirect traces of redactions in 4, 10, 11, and 12 books for the part of contemporary history (Decades III and IV), and in 8, 9, 11 and finally 20 books for the part of more ancient history (Decades I and II). His conception of history, therefore, changed, moving from a vision focused on the contemporary period towards another one oriented towards long reconstructions, from a macro-regional and particular perspective to another one wider and more general. Blondus preferred to give voice to the events, because he was fully convinced that they could be intelligible without intermediaries. However, he was also convinced that the history was a school of wisdom, which could suggest solutions to the faults detected in the contemporary world. And in his work sometimes he outlines solutions which appear constantly oriented towards the project of a political-institutional model, which can guarantee order and harmony between the parties.La composizione delle Historiae ab inclinatione Romanorum imperii, o Decadi, accompagnò l’intera vita di Biondo Flavio. La loro compilazione fu lunga, e non sempre lineare fu la loro concezione: ci sono rimaste tracce indirette di redazioni in 4, 10, 11 e 12 libri per la parte di storia contemporanea (Decades III e IV); e in 8, 9, 11 e finalmente 20 libri per la parte di storia più antica (Decades I e II). La sua concezione della storia, di conseguenza, mutò, passando da una visione legata alla contemporaneità a una orientata verso le ricostruzioni lunghe; da una prospettiva più macro-regionale e particolare a una più ampia e generale. Biondo preferiva dar voce agli eventi, convinto, evidentemente, che essi si potessero rendere intelligibili da soli. Tuttavia, egli era convinto anche che la storia fosse scuola di saggezza, e che permettesse, pertanto, di suggerire soluzioni ai guasti ravvisati nella contemporaneità. E, nella sua opera, talvolta egli delinea soluzioni che appaiono costantemente orientate verso la progettazione di un modello politico-istituzionale che possa garantire ordine e armonia tra le parti
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