4 research outputs found
Laser scattering, optical constants and connection to other material performances (Kerr constant, mobility/diffusion coefficient/electrophoresis and depolarization)
Scattering of optical photons from the view of parallel methods related to absorption, scattering, fluorescence, reflection with inclusion of the polarization states of laser beams from experiment and theory give many possibilities for obtaining indirect data on material, processes, and dynamics. As a method with minimal perturbations, if low power beams are involved, certain type of data is provided. In fundamental dependences of various material properties, many phenomenological and basic laws are covered. Several coupled variables, primarily with the processes of scattering, pointing out further possibilities for linking the obtained theoretical or experimental results were presented. By including simulations, this associates with biological environments / variables for properties equivalent to defined tissues, cells, and characteristics. Along with selected formalisms including Stokes vectors and scattering matrices, a biological cell as an object can be monitored in time and influence of various environments could be predicted. Connecting Kerr’s effect with depolarization and scattering makes the complete description of molecule possible. Angular scattering observation with experimental possibilities gives the fastest practical data. This enables interpretation of E. coli with the application of Stokes vector formalisms. A relatively small number of material constants for many simulation cases could give draft estimation, but the experiment depends on the measuring devices and samples. The necessary symmetries showing the size of the scattering centers are analyzed, with the scattering data for some liquids (known / less known). From measured data, depolarization could be calculated, and with refractive index (molar refraction) connection with Kerr effect/ birefringence for selected solutions and behavior of molecules could be monitored. From the experimental Rayleigh factors, cross section (apparent/ effective) and attenuation coefficients for pure liquids were calculated. An approach for the correct assessment of the measurement uncertainty in the process of calibration of polyethylene samples.
Keywords: Scattering, laser, Kerr effect, depolarization, bacteria, Mieplo
Safety and immunogenicity of a seasonal trivalent inactivated split influenza vaccine: a double blind, phase III randomized clinical trial in healthy Serbian adults
This study was a phase III, multicenter, double-blind, randomized, placebo-controlled trial to evaluate the safety and immunogenicity of a seasonal trivalent split, inactivated influenza vaccine (TIV) in healthy Serbian adults between the ages of 18 and 65 years. This egg-based vaccine was manufactured by the Institute of Virology, Vaccines and Sera, Torlak, Belgrade, Serbia. A total of 480 participants were assigned randomly in a ratio of 2:1 to receive a single intramuscular dose (0.5 ml) of the vaccine (15 µg of hemagglutinin per strain) or placebo (phosphate-buffered saline). Participants were monitored for safety, including solicited and unsolicited adverse events (AEs) and serious adverse events (SAEs). No SAEs related to vaccination were reported. Injection site pain (51.3%), injection site tenderness (40.4%), tiredness (17.0%), and headache (15.1%) were the most commonly reported solicited events in the vaccine group. Incidence of related unsolicited AEs was low (1.3%) among vaccinees. Hemagglutinin inhibition (HAI) titers were measured before and 21 days after vaccination in 151 participants. Overall, HAI seroconversion rates to H1 and H3 were observed in 90.1% and 76.2% of vaccinees, respectively. For B antigen, it was 51.5%, likely due to high pre-vaccination titers. Post-vaccination seroprotection rates were in the range of 78.2–95.0% for the three antigens. Post-vaccination geometric mean titers (GMT) were at least 3.8 times higher than baseline levels for all the three strains among vaccinees. Overall, the study showed that the vaccine was safe and well tolerated, and induced a robust immune response against all three vaccine strains., ClinicalTrials.gov identifier: NCT02935192, October 17, 201
Selective infrared absorption and refraction of symmetrical two-layered molecular nanofilms
We have supplemented the already formulated microscopic theory of optical properties of very ultrathin molecular films (quantum nanofilms), i.e., quasi 2D systems parallel to XY planes bounded by two surfaces. The exposure of nanofilms to the external electromagnetic fields has resulted in the creation of excitons, but different than bulk ones in one direction perpendicular to surfaces. The analysis of the dielectric response of the system to perturbation of an external electromagnetic field shows that optical properties of these crystalline nanosystems for low exciton concentration of Frenkel's excitons strongly depend on boundary parameters and the thickness of the film. In addition, the dynamical absorption and the refraction coefficient show a very narrow and discrete dependence of external electromagnetic field frequency, which is the consequence of both resonance and quantum size effects. Influences of boundary conditions on optical characteristics (through the analyses of dynamical absorption and refraction indices) of these nanostructures were specially and in details explored. The emission and the luminescence spectrum of the whole film have been analyzed and the results compared to experimental data show very good behavior and very good coordination