Probing Water State during Lipidic Mesophases Phase Transitions

We investigate the static and dynamic states of water network during the phase transitions from double gyroid ((Formula presented.)) to double diamond ((Formula presented.)) bicontinuous cubic phases and from the latter to the reverse hexagonal (HII) phase in monolinolein based lipidic mesophases by combining FTIR and broadband dielectric spectroscopy (BDS). In both cubic(s) and HII phase, two dynamically different fractions of water are detected and attributed to bound and interstitial free water. The dynamics of the two water fractions are all slower than bulk water due to the hydrogen-bonds between water molecules and the lipid's polar headgroups and to nanoconfinement. Both FTIR and BDS results suggest that a larger fraction of water is hydrogen-bonded to the headgroup of lipids in the HII phase at higher temperature than in the cubic phase at lower temperature via H-bonds, which is different from the common expectation that the number of H-bonds should decrease with increase of temperature. These findings are rationalized by considering the topological ratio of interface/volume of the two mesophases.ISSN:1433-7851ISSN:1521-3773ISSN:0570-083

Relaxation of Vibrational Excitons in Molecular-Ionic Crystal s Measured by Picosecond Time-Resolved CARS

The decay times of the internal vibrations in K2S04, KCl04, NaN03 and CaC03 single crystals have been measured at different temperature s by picosecond time-resolved CARS. The low temperature experimental data and their temperature dependence are interpreted on the basis of an energy relaxation mechanism, involving two-phonon and higher order decay processes

Sub-Nyquist Field Trial Using Time Frequency Packed DP-QPSK Super-Channel Within Fixed ITU-T Grid

Sub-Nyquist time frequency packing technique was demonstrated for the first time in a super channel field trial transmission over long-haul distances. The technique allows a limited spectral occupancy even with low order modulation formats. The transmission was successfully performed on a deployed Australian link between Sydney and Melbourne which included 995 km of uncompensated SMF with coexistent traffic. 40 and 100 Gb/s co-propagating channels were transmitted together with the super-channel in a 50 GHz ITU-T grid without additional penalty. The super-channel consisted of eight sub-channels with low-level modulation format, i.e. DP-QPSK, guaranteeing better OSNR robustness and reduced complexity with respect to higher order formats. At the receiver side, coherent detection was used together with iterative maximum-a-posteriori (MAP) detection and decoding. A 975 Gb/s DP-QPSK super-channel was successfully transmitted between Sydney and Melbourne within four 50GHz WSS channels (200 GHz). A maximum potential SE of 5.58 bit/s/Hz was achieved with an OSNR=15.8 dB, comparable to the OSNR of the installed 100 Gb/s channels. The system reliability was proven through long term measurements. In addition, by closing the link in a loop back configuration, a potential SE*d product of 9254 bit/s/Hz*km was achieved

Unravelling the ultrafast dynamics of a N-BODIPY compound

Although the photophysics of BODIPY compounds has been widely investigated in the last few years, their analogues N-BODIPY, with nitrogen substitution at the boron center, did not receive comparable attention. In this work we report the synthesis and photochemical characterization of a substituted N-BODIPY compound, by means of a combined theoretical and spectroscopic approach. Compared to a standard BODIPY, the compound under investigation presents a lower fluorescence quantum yield (QY) in the visible region. The excited state relaxation dynamics of the dye was studied in different solvents, showing further fluorescence quenching in polar solvents, and excited state decay rates strongly dependent on the environment polarity. The role of the pendant moieties and the involvement of charge transfer states in the excited state dynamics was experimentally addressed by transient absorption spectroscopy, and further analyzed with TD-DFT calculations, which allowed precise assignment of the transient signals to the correspondent electronic configuration. The complete picture of the N-BODIPY behavior shows the presence of both charge transfer and localized states, influencing the observed photophysics to different amounts, depending on the excitation conditions and the surrounding environment

How many chronic myeloid leukemia patients who started a frontline second-generation tyrosine kinase inhibitor have to switch to a second-line treatment? A retrospective analysis from the monitoring registries of the italian medicines agency (AIFA)

The frequency of patients who switch to a second-line therapy from a frontline second-generation (2gen) tyrosine kinase inhibitor (TKI) such as dasatinib and nilotinib, is still substantially unknown. We retrospectively investigated a large series of chronic phase chronic myeloid leukemia (CP-CML) patients initially treated with 2gen TKIs monitored through the Italian Medicines Agency (AIFA Agenzia Italiana del farmaco) registries. Overall, 2420 patients were analyzed over a period of 6 years. One hundred and fifty-seven patients (16.3%) treated with dasatinib and 164 treated with nilotinib (11.3%) have switched to another drug, with an overall frequency of 13.2%. In the dasatinib cohort, 39.4% of patients changed treatment for failure and 36.3% for intolerance as compared to 45.7% and 27.4% respectively in the nilotinib cohort. Overall, the median time to switch due to resistance was 293 days, whereas it was 317 days in case of intolerance. Resistance was observed mainly in younger male patients with high-risk features, while intolerance was not related to any baseline parameter. After resistance/intolerance to nilotinib, the majority of patients switched to dasatinib (53.8%) whereas in case of frontline dasatinib to ponatinib (43.2%). To the best of our knowledge these data provide the first report on the frequency of discontinuation of frontline 2gen TKIs and on the main causes and pattern of choice to a second-line therapy in the real-life setting