Alessandro Soldi - Academia.edu (original) (raw)
Papers by Alessandro Soldi
The AGILE Mission, a wide field-of-view instrument sensitive in the 30 MeV - 50 GeV band combined... more The AGILE Mission, a wide field-of-view instrument sensitive in the 30 MeV - 50 GeV band combined, for the first time in high-energy astrophysics, with a 10-40 keV X-ray monitor, will explore a wide variety of celestial phenomena including active galactic nuclei (AGNs), gamma-ray bursts (GRBs), diffuse Galactic and extragalactic emission, pulsars, and unidentified gamma-ray sources. We report on the progress of scientific programs being developed by members of the AGILE collaboration in each of these areas.
Biophysical Journal, 2009
Amyloid fibril formation is a distinctive hallmark of a number of degenerative diseases. In this ... more Amyloid fibril formation is a distinctive hallmark of a number of degenerative diseases. In this process, protein monomers self-assemble to form insoluble structures that are generally referred to as amyloid fibrils. We have induced in vitro amyloid fibril formation of a PDZ domain by combining mechanical agitation and high ionic strength under conditions otherwise close to physiological (pH 7.0, 37 degrees C, no added denaturants). The resulting aggregates enhance the fluorescence of the thioflavin T dye via a sigmoidal kinetic profile. Both infrared spectroscopy and circular dichroism spectroscopy detect the formation of a largely intermolecular beta-sheet structure. Atomic force microscopy shows straight, rod-like fibrils that are similar in appearance and height to mature amyloid-like fibrils. Under these conditions, before aggregation, the protein domain adopts an essentially native-like structure and an even higher conformational stability (DeltaG(U-F)(H2O)). These results show a new method for converting initially folded proteins into amyloid-like aggregates. The methodological approach used here does not require denaturing conditions; rather, it couples agitation with a high ionic strength. Such an approach offers new opportunities to investigate protein aggregation under conditions in which a globular protein is initially folded, and to elucidate the physical forces that promote amyloid fibril formation.
In this presentation we review the current status of the AGILE Mission. AGILE, a Small Scientific... more In this presentation we review the current status of the AGILE Mission. AGILE, a Small Scientific Mission of the Italian Space Agency (ASI) will study celestial sources emitting in the gamma-ray energy band 30 MeV - 50 GeV, combined - for the first time in high-energy gamma-ray astronomy - with monitoring capabilities in the hard X-ray band 10 - 40 keV. Because of its large field of view ( ˜ 3 sr), the small deadtime (lower than 200 microsec), and broad-band detection capabilities, AGILE is ideal to perform a large number of tasks: monitoring active galactic nuclei (AGNs),detecting gamma-ray bursts (GRBs) with high efficiency, mapping the diffuse Galactic and extragalactic emission, studying pulsed gamma-ray emission from radiopulsars, and monitoring the many unidentified sources contributing to their unveiling. The AGILE Mission is planned to operate during the years 2004-2006 and its Science Program emphasizes the quick reaction to transients and rapid communication of science data for fast follow-up multiwavelength observations.
The AGILE Mission, a wide field-of-view instrument sensitive in the 30 MeV - 50 GeV band combined... more The AGILE Mission, a wide field-of-view instrument sensitive in the 30 MeV - 50 GeV band combined, for the first time in high-energy astrophysics, with a 10-40 keV X-ray monitor, will explore a wide variety of celestial phenomena including active galactic nuclei (AGNs), gamma-ray bursts (GRBs), diffuse Galactic and extragalactic emission, pulsars, and unidentified gamma-ray sources. We report on the progress of scientific programs being developed by members of the AGILE collaboration in each of these areas.
Biophysical Journal, 2009
Amyloid fibril formation is a distinctive hallmark of a number of degenerative diseases. In this ... more Amyloid fibril formation is a distinctive hallmark of a number of degenerative diseases. In this process, protein monomers self-assemble to form insoluble structures that are generally referred to as amyloid fibrils. We have induced in vitro amyloid fibril formation of a PDZ domain by combining mechanical agitation and high ionic strength under conditions otherwise close to physiological (pH 7.0, 37 degrees C, no added denaturants). The resulting aggregates enhance the fluorescence of the thioflavin T dye via a sigmoidal kinetic profile. Both infrared spectroscopy and circular dichroism spectroscopy detect the formation of a largely intermolecular beta-sheet structure. Atomic force microscopy shows straight, rod-like fibrils that are similar in appearance and height to mature amyloid-like fibrils. Under these conditions, before aggregation, the protein domain adopts an essentially native-like structure and an even higher conformational stability (DeltaG(U-F)(H2O)). These results show a new method for converting initially folded proteins into amyloid-like aggregates. The methodological approach used here does not require denaturing conditions; rather, it couples agitation with a high ionic strength. Such an approach offers new opportunities to investigate protein aggregation under conditions in which a globular protein is initially folded, and to elucidate the physical forces that promote amyloid fibril formation.
In this presentation we review the current status of the AGILE Mission. AGILE, a Small Scientific... more In this presentation we review the current status of the AGILE Mission. AGILE, a Small Scientific Mission of the Italian Space Agency (ASI) will study celestial sources emitting in the gamma-ray energy band 30 MeV - 50 GeV, combined - for the first time in high-energy gamma-ray astronomy - with monitoring capabilities in the hard X-ray band 10 - 40 keV. Because of its large field of view ( ˜ 3 sr), the small deadtime (lower than 200 microsec), and broad-band detection capabilities, AGILE is ideal to perform a large number of tasks: monitoring active galactic nuclei (AGNs),detecting gamma-ray bursts (GRBs) with high efficiency, mapping the diffuse Galactic and extragalactic emission, studying pulsed gamma-ray emission from radiopulsars, and monitoring the many unidentified sources contributing to their unveiling. The AGILE Mission is planned to operate during the years 2004-2006 and its Science Program emphasizes the quick reaction to transients and rapid communication of science data for fast follow-up multiwavelength observations.