0000000000307965
AUTHOR
G Schirò
I cubicoli VIII.19 e X.10 nella catacomba di Villagrazia di Carini (Palermo)
Dati di scavo, analisi strutturale e degli apparati pittorici dei cubicoli al momento più rappresentativi della catacomba.
Protein dynamical transition vs. liquid-liquid phase transition in protein hydration water
In this work, we compare experimental data on myoglobin hydrated powders from elastic neutron scattering, broadband dielectric spectroscopy, and differential scanning calorimetry. Our aim is to obtain new insights on the connection between the protein dynamical transition, a fundamental phenomenon observed in proteins whose physical origin is highly debated, and the liquid-liquid phase transition (LLPT) possibly occurring in protein hydration water and related to the existence of a low temperature critical point in supercooled water. Our results provide a consistent thermodynamic/dynamic description which gives experimental support to the LLPT hypothesis and further reveals how fundamental …
Catacomba di Villagrazia di Carini (PA). Scavi 2008-2010
Il poster presenta gli esiti della ricerca archeologica nella catacomba paleocristiana di Villagrazia di Carini negli anni 2008-2010. Alla rimozione degli strati di interro alluvionale, che ingombravano i settori indagati (gallerie VII-X e cubicolo X.20), si è affiancata l'analisi delle consistenze architettoniche, che ha consentito di delineare le diverse fasi della frequentazione per uso funerario. Ulteriori interessanti dati sono emersi dall'analisi dei resti osteologici e dalle operazioni di pulitura delle pareti dagli strati fangosi, che ha riportato alla luce nuovi apparati decorativi pittorici. The text introduces the results of the archaeological excavations carried out during the y…
Ultrafast myoglobin structural dynamics observed with an X-ray free-electron laser.
Light absorption can trigger biologically relevant protein conformational changes. The light-induced structural rearrangement at the level of a photoexcited chromophore is known to occur in the femtosecond timescale and is expected to propagate through the protein as a quake-like intramolecular motion. Here we report direct experimental evidence of such ‘proteinquake’ observed in myoglobin through femtosecond X-ray solution scattering measurements performed at the Linac Coherent Light Source X-ray free-electron laser. An ultrafast increase of myoglobin radius of gyration occurs within 1 picosecond and is followed by a delayed protein expansion. As the system approaches equilibrium it underg…