Ultrafast spectroscopy, superluminescence and theoretical modeling of a two-photon absorbing fluorene derivative.

A comprehensive study of photophysical and photochemical properties of an unsymmetrical fluorene derivative is presented, including linear absorption, fluorescence excitation anisotropy, photochemical stability, steady-state fluorescence, and fluorescence lifetimes in organic solvents of different polarities. Nonlinear optical properties were investigated using Z-scan measurements of degenerate two-photon absorption and femtosecond pump-probe spectroscopy. The strongly fluorescent compound exhibited good photostability, positioning it for use in a number of applications. A dramatic increase in fluorescence intensity along with spectral narrowing was observed under femtosecond pumping, demonstrating amplified spontaneous emission. An extensive set of experimental data is rationalized based on essential state models.

[FEATURES OF YEAST METABOLISM IN THEIR RECIRCULATION PROVIDED ALCOHOL FERMENTATION OF MOLASSES WORT].

The subject of investigation are the peculiarities of yeast metabolism of Saccharomyces cerevisiae M-5 strain in the alcoholic fermentation of molasses wort of increased concentration of dry substances in terms of periodic and continuous fermentation. For periodic alcohol fermentation of wort concentrate having 27 % dry substance content it was established, that 60g /dm³ is the optimal value for inoculate yeast. This results in the maximal accumulation of ethanol in the mature mash (11.5 vol. %), in the deep assimilation of carbohydrates and by the generation of fewer amount of glycerin. By industrial uninterrupted-mode investigations the increase in activity of starting enzymes of glycolysis and strengthening in the capacity of recirculated yeast have been demonstrated. For the first time we show, that this is a consequence of adaptation of yeast to the cultural medium as a result of long-term stay of yeast in it. The increase of the inflow speed of molasses wort into the main fermenter of the battery from 0.43 to 0.57 h⁻¹ improves physiological parameters of recirculated yeast. Also, this reduces the accumulation of secondary products of fermentation (ethers, aldehydes, higher alcohols, glycerin). At the same time, this approach allows to increase the yield of alcohol from the saccharose by 1.84 % and to enhance the productivity with respect to ethanol from 2.3 to 3.8 g/dm³ ×h.

Design and electronic structure of new styryl dye bases: steady-state and time-resolved spectroscopic studies.

A comprehensive investigation of the electronic structure and fast relaxation processes in the excited states of new styryl base-type derivatives was performed using steady-state, pico-, and femtosecond time-resolved spectroscopic techniques. Linear photophysical parameters of new compounds, including steady-state absorption, fluorescence, and excitation anisotropy spectra, were obtained in a number of organic solvents at room temperature. A detailed analysis of the fluorescence lifetimes and ultrafast relaxation processes in the electronically excited state of the styryl bases revealed an important role of solvate dynamics and donor-acceptor strength of the molecular structures in the formation of their excited state absorption spectra. Experimental data were in good agreement with quantum chemical calculations at the time dependent density functional theory level, combined with a polarizable continuum model.

One- and two-photon fluorescence anisotropy of selected fluorene derivatives.

The steady-state excitation anisotropy spectra of fluorene derivatives were measured in viscous solvents, under the one- and two-photon excitation, over a broad spectral range (UV-Visible). The orientation of their absorption transition moments for the first, S0 --> S1, and second, S0 --> S2, excited states were determined. It was shown experimentally that a decrease in the angle between S0 --> S1 and S0 --> S2 transitions corresponded to an increased value of two-photon absorption (2PA) cross section for these molecules. Two-photon excitation anisotropy was nearly constant over the spectral region investigated (in contrast to one-photon excitation anisotropy spectra) and can be roughly explained by a simple model of 2PA based on the single intermediate state approximation. For comparison, the same trend in two-photon excitation anisotropy was observed for Rhodamine B in glycerol.

[The use of Ukrainian laferon in the combined treatment of patients with chronic myeloid leukemia]. / Zastosuvannia vitchyznianoho laferonu u kompleksnomu likuvanni khvorykh na khronichnu miieloïdnu leikemiiu.

A study was made into the effect of laferon on effectiveness of treatment of patients with chronic myeloid leukemia (CML). The authors have reached the conclusion that drug tolerance in the patients is fairly good. The number of negative reactions within a few days of the start of laferon therapy did not exceed the level reported from other countries. Small series and short-term follow-up does not allow judgement about effects of the drug on survival but one can say with certainty that the employment of laferon in the treatment programme for CML in different categories of risk permits achieving clinical and hematological compensation on more frequent occasions. The quality of the patients' life gets improved. Chemotherapy was found to lessen the risk for infectious and inflammatory complications.

[The clinico-physiological validation of the use of the endolymphatic route for antibiotic administration for preventing the translocation of intestinal microflora during the treatment of sepsis patients]. / Kliniko-fiziologicheskoe obosnovanie ispol'zovaniia éndolimfaticheskogo puti vvedeniia antibiotikov dlia profilaktiki translokatsii kishechnoi mikroflory pri lechenii bol'nykh sepsisom.

One of the main mechanisms of generalization of infection in purulent-inflammatory processes of the abdominal cavity, retroperitoneal space and pelvis minor is translocation of the pathogenic microflora of the intestine in the lymphatic system via regional lymphatic nodes with subsequent rupture into the systemic circulation. Endolymphatic administration of antibacterial agents into the peripheral lymphatic vessel favours saturation of the reticuloendothelial structures of the lymph nodes by the antibiotic agent that increases their barrier function and, thus, prevents generalization of the infection and development of polyorganic insufficiency.