A functionalized polymer film allowing for a complete and straightforward second-harmonic generation (SHG)-assisted high-contrast writing−reading−erasing−writing sequence is proposed. The whole ...process is supported by the reversible photoinduced dimerization of a coumarin chromophore and enables efficient optical data storage that can be detected only by SHG imaging.
Non-specific acute low back pain (LBP) is a common health problem that may be accompanied by muscle spasm and decreased mobility. The combination of non-steroidal anti-inflammatory drugs and muscle ...relaxants represents an advantageous therapeutic option, however, available data on their combined use are conflicting. This prospective, randomized, single-blind, two-parallel-group trial assessed the efficacy of a single intramuscular (IM) injection of the fixed-dose combination (FDC) diclofenac (75 mg)-thiocolchicoside (4 mg/4 ml) product (test treatment) compared to diclofenac (75 mg/3 ml) alone (reference treatment) for the symptomatic relief of acute LBP. Tolerability and safety were also assessed as secondary variables.
One hundred thirty-four patients were enrolled (safety population) and randomly allocated to the combination or single-agent regimen. Pain intensity and muscle spasm, assessed respectively by the patient-reported visual analogue scale and investigator-performed finger-to-floor distance test, were determined prior to the injection as well as 1 and 3 h post-injection in 123 patients (per-protocol population). The patients were blinded to treatment. Safety was assessed up to 24 h post-injection.
The test treatment was superior in both alleviating the pain intensity and reducing the finger-to-floor distance at both 1 (p < 0.01 and p = 0.023 respectively) and 3 h post-injection (p < 0.01). A higher percentage of patients experienced > 30% reduction in pain intensity at 1 and 3 h with the test treatment (p = 0.037 and p < 0.01 respectively). The corresponding VAS (SD) scores for the test treatment group were at baseline, 1 and 3 h post-injection 72.03 (± 11.72), 45.37 (± 16.28) and 31.56 (± 15.08) respectively and for the reference treatment group 65.20 (± 12.16), 48.98 (± 18.76) and 44.52 (± 17.33) respectively. No adverse effects were reported with the combination treatment, whereas two patients treated with diclofenac reported dizziness.
The FDC treatment is an effective and well-tolerated option for the symptomatic treatment of LBP. Clinical and patient-reported assessments confirmed that a single IM injection of FDC diclofenac-thiocolchicoside was more effective than diclofenac alone in conferring rapid and sustained improvement in mobility and pain intensity.
EudraCT No: 2017-004530-29 Available at https://eudract.ema.europa.eu/ Registered 04 Dec 2017.
The rod-like molecule bis((4-(4-pyridyl)ethynyl)bicyclo2.2.2oct-1-yl)buta-1,3-diyne, 1, contains two 1,4-bis(ethynyl)bicyclo2.2.2octane (BCO) chiral rotators linked by a diyne fragment and ...self-assembles in a one-dimensional, monoclinic C2/c centrosymmetric structure where two equilibrium positions with large occupancy imbalance (88% versus 12%) are identified on a single rotor site. Combining variable-temperature (70–300 K) proton spin–lattice relaxation, 1H T 1 –1, at two different 1H Larmor frequencies (55 and 210 MHz) and DFT calculations of rotational barriers, we were able to assign two types of Brownian rotators with different activation energies, 1.85 and 6.1 kcal mol–1, to the two 1H spin–lattice relaxation processes on the single rotor site. On the basis of DFT calculations, the low-energy process has been assigned to adjacent rotors in a well-correlated synchronous motion, whereas the high-energy process is the manifestation of an abrupt change in their kinematics once two blades of adjacent rotors are seen to rub together. Although crystals of 1 should be second harmonic inactive, a large second-order optical response is recorded when the electric field oscillates in a direction parallel to the unique rotor axle director. We conclude that conformational mutations by torsional interconversion of the three blades of the BCO units break space-inversion symmetry in sequences of mutamers in dynamic equilibrium in the crystal in domains at a mesoscopic scale comparable with the wavelength of light used. A control experiment was performed with a crystalline film of a similar tetrayne molecule, 1,4-bis(3-((trimethylsilyl)ethynyl)bicyclo1.1.1pent-1-yl)buta-1,3-diyne, whose bicyclopentane units can rotate but are achiral and produce no second-order optical response.
Optical data storage was performed with various thin polymer films containing coumarin-based derivatives and by using femtosecond laser pulses as well as two-photon absorption processes. Exploring ...the photodimerization attribute of coumarin derivatives and using appropriate irradiation wavelengths, recording/erasing processes could be carried out in the same area. Second harmonic generation microscopy was used to read the stored information.
We present the nonlinear absorption investigation of an electroactive ligand and two ruthenium and iron metal complexes under 532 nm, 30 ps laser excitation, by the "open aperture" Z-scan technique. ...Significant nonlinear optical parameters have in all cases been measured, while the nonlinear attribute has been found to change from saturable to reverse saturable absorption between the initial ligand and its complexes.
In this work, the second- and third-order nonlinear optical response of spin-deposited thin films of three different push−pull side chain azobenzene polymers is investigated by the second- and ...third-harmonic Maker fringes techniques using 30 ps laser pulses at a fundamental wavelength of 1064 nm. Measurements were carried out before and after aligning the chromophores by corona poling of the films, while different polarization configurations have been utilized. Strong dependence of the response upon the structure of the systems has been found, which is related to the different charge transfer within the molecules. The reported findings are compared with already published results.
The saturable absorption behaviour associated with chalcogenide thin films has been investigated and optimized using Z-Scan Technique. Huge saturable absorption responses (of the order of 10^-7 m/W) ...were observed for the Bismuth Selenide thin films, which depend on material characteristics and the laser parameters. An approach in which the application of the saturable absorber thin films for super-resolved laser inscriptions has been discussed and a theoretical analysis of the super-resolution efficiency of the thin films has been made.
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