Editoria - luglio 2018
Giornale di Fisica Vol. 59 N. 2 (2018)
È online in OPEN ACCESS per 30 giorni e in stampa il secondo numero del Vol. 59 del 2018.
Accanto a lavori quali "Esempi di discretizzazione di orbite nella fisica classica" di G. Bei e D. Passaro, "Un compact disc sfiorato da raggi luminosi" di R. De Luca, M. Di Mauro, O. Fiore e A. Naddeo, "Tutta la luce del prisma di Newton: effetti delle riflessioni multiple interne" di A. Parretta, "Le parole della Fisica: Pressione" di C. Frontali e "Novant'anni del contatore di Geiger e Müller" di A. Bettini, segnaliamo l'articolo di C. Lubritto e M. F. Alberghina
"I beni culturali e la fisica"
nel quale gli autori illustrano come il contributo della fisica allo studio dei beni culturali (la archeometria) stia diventando cruciale per la valorizzazione e conservazione del patrimonio storico-artistico e archeologico grazie alle informazioni che le metodologie scientifiche forniscono alla conoscenza delle tecniche esecutive e dei materiali impiegati.
NOVITÀ: dal 2019 i soci in regola della Società Italiana di Fisica avranno accesso gratuitamente alla versione online del Giornale di Fisica.
La Rivista del Nuovo Cimento Vol. 41 N. 8 (2018)
Attosecond spectroscopy of bio-chemically relevant molecules
F. Calegari, A. Trabattoni, E. Månsson, J. B. Greenwood, P. Decleva, F. Martìn, M. Nisoli
Understanding the role of the electron dynamics in the photochemistry of bio-chemically relevant molecules is key to getting access to the fundamental physical processes leading to damage, mutation and, more generally, to the alteration of the final biological functions. Sudden ionization of a large molecule has been proven to activate a sub-femtosecond charge flow throughout the molecular backbone, purely guided by electronic coherences, which could ultimately affect the photochemical response of the molecule at later times. We can follow this ultrafast charge flow in real time by exploiting the extreme time resolution provided by attosecond light sources. This review provides an introduction to attosecond technology and its application to molecular spectroscopy. Both the experimental techniques and the advanced theoretical models used to capture the photo-induced electron dynamics in complex molecules are described. Advancements in this new exciting field will open new important perspectives in photochemistry and photobiology.
EPJ E – Highlights
Translocation of Polyampholytes and Intrinsically Disordered Proteins
A. Johner, J.F. Joanny
Nature’s way of allowing proteins across its gates, through porous biological membranes, depends, among others, on their electrical charge. For a protein to cross this type of membrane, it needs to be stimulated by an electrical field. A new study focuses on a particular kind of proteins that have multiple functions - dubbed Intrinsically Disordered Proteins - because the electric charge disorder on their surface makes it possible for them to take multiple shapes. In the work, recently published in EPJ E, Albert Johner from the Charles Sadron Institute (part of the CNRS) in Strasbourg, France and Jean-Francois Joanny from Paris reveal how the mixed electrical charge at the ends of the proteins influences biological membrane crossing. This has potential implications for our understanding of how proteins travel across the body, and of disease mechanisms.
EPJ Plus – Highlights
The magnetic field circulation counterpart to Biot-Savart's law
J. M. Ferreira, J. Anacleto
A new study reveals how to best evaluate the circulation of magnetic fields around closed loops. Concerns about the effects of magnetic fields on human health require careful monitoring of our exposure to them. Mandatory exposure limits have been defined for electric and hybrid vehicle architectures, in domestic and work environments, or simply to shelter sensitive devices from unintended sources of magnetic disturbance. In a new study published in EPJ Plus, physicists Jose Manuel Ferreira and Joaquim Anacleto from the Trás-os-Montes e Alto Douro University in Portugal develop a method for deriving an approximate value of the circulation around a loop of the magnetic field generated by the flow of electric current in an arbitrarily-shaped wire of a given length.