On the Analytic Part of Univalent Harmonic Mappings

© 2018, Springer International Publishing AG, part of Springer Nature. In this article we obtain two sharp results concerning the analytic part of harmonic mappings f= h+ g¯ from the class SH0(S) which was recently introduced by Ponnusamy and Sairam Kaliraj. For example, we get the sharp estimate for | arg h′(z) | in the case when |z|≤1/2 and obtain the sharp radius of convexity for h. Our approach is applicable to a more general situation. Finally, we determine simple condition on the analytic part of univalent harmonic mappings so that it is in Hpspaces for 0 < p< 1 / 3

Evaluation of the ecological state of water reservoirs using the COI protein of zooplankton

Water reservoirs located in industrial areas are commonly under strong anthropogenic pressure and an efficient monitoring of their ecological state is desired. Bioindication using the zooplanktonic organisms is one of the most relevant approaches widely used for evaluation of the ecological state of waters. World widely, the water-living species are identified visually and results depend on expert's opinion and subjectivity. In this study an alternative method for organism identification using the marker protein cytochrome oxidase subunit 1 (COI) is proposed. Multiple alignments by Clustal Omega algorithm of 95 amino acid sequences of available COI proteins from zooplanktonic organisms included in the V.Sladechek's list (1973) was performed. A short unique (4-33) amino acid sequences were identified in 23 proteins of organisms normally used as bioindicators of water saprobity, a common indicator of ecological state of water body. This fact allows further developing the antibodies for direct qualification and quantification of the indicator species in the probe. We suggest that this approach represents a new technique for the ecological evaluation of ecological state of waters by using the metaproteom of water living organisms

Simulator Performance vs. Neurophysiologic Monitoring: Which is More Relevant to Assess Driving Impairment?

Previously, we reported on circadian variation in driving simulator performance and neurophysiologic evidence of sleep intrusion into consciousness in a pilot study of healthy individuals. We have since expanded this “normative” sample and run a prospective comparison study with a sample of clinical patients reporting excessive daytime sleepiness (EDS) as a chief complaint. Thirty healthy adults (mean age of 31.3 ± 11.5) and 27 EDS patients (47.0 ± 13.7) with valid driver’s licenses were included. Subjects performed four intentionally soporific 30-minute driving simulations at two-hour intervals while undergoing continuous EEG monitoring for microsleep (MS) episodes. Measured variables included: subjective ratings of sleepiness and alertness prior to each drive, lane position accuracy, mean speed, speed deviation, mean reaction time (RT) to “virtual” wind gusts as well as off-road events, i.e., “crashes.” In comparing normative individuals and EDS patients, significant between-group differences were found between subjective ratings, RT, crashes and MS. Both groups showed a significant a tendency towards RT slowing during afternoon drives, with this circadian effect appearing most pronounced for EDS patients. Significant between-group differences were also found on subjective ratings of sleepiness and alertness, although diurnal fluctuation of subjective sleepiness ratings was significant only for the EDS group. Objective EEG MS monitoring demonstrated escalating sleep intrusion with repeated drives in both groups, but particularly for the EDS group. Total crash rates were three times higher in EDS patients, with an increasing trend towards crash-proneness in the late afternoon. In summary, we found significantly impaired performance on some, though not all, driving parameters for EDS patients. While increased crash rate may be the most dramatic of these, slowing of RT was the most statistically robust. EEG monitoring was able to document increased propensity towards MS episodes in patients with EDS, which we suggest is causative in creating this impairment. It remains unclear whether a neurophysiologic or simulator approach captures impairment due to sleepiness with greater sensitivity and specificity. A hybrid approach combining data from both sources may be optimal, and also could be integrated in commercial vehicle use. We suggest that the need for a more accurate hospitalbased screening tool for assessment of driving impairment due to sleep disorders remains an important issue for physicians and legislators dealing with driving competency

The biosynthesis of new secretory high-molecular-weight ribonucleases in Bacillus intermedius and Bacillus subtilis

The investigation of new secretory ribonucleases, the Bacillus intermedius binase II expressed in the recombinant B. subtilis strain 3922 and the native RNase Bsn of B. subtilis, showed that they are synthesized in the growth retardation phase, when inorganic phosphate is exhausted in the medium. The biosynthesis of these ribonucleases was found to be suppressed by the presence of inorganic phosphate in the medium and activated by small amounts of the transcriptional inhibitor actinomycin D. The cultivation media of the producing strains were optimized for the maximum production of the enzymes

2(5H)-Furanone Derivatives as Inhibitors of Staphylococcal Biofilms

© 2016, Springer Science+Business Media New York.The opportunistic bacteria Staphylococcus aureus and Staphylococcus epidermidis often form rigid biofilms on wounds and artificial surfaces and thereby become extremely resistant to antimicrobials. Here, we report the effect of four novel 2(5H)-furanone derivatives on the cell growth and biofilm formation by these microorganisms. Using the differential fluorescence staining of viable and dead cells, we demonstrated that furanones increase the antibacterial efficacy of chloramphenicol against both biofilm-embedded S. aureus and S. epidermidis with F35 being the most efficient compound, probably by increasing the accessibility of cells against antimicrobials. Compounds F6, F8, and F83 inhibited the biofilm formation at concentrations of 2.5–10 μg/ml, although exhibiting high cytotoxicity for human skin fibroblasts with CC50 of 0.5–1.1 μg/ml. F35 demonstrated minimal biofilm inhibition concentration of 10 μg/ml, while its cytotoxicity was ten times lower than that of the other compounds (CC50 13.1 μg/ml), suggesting its chemotype seems a promising starting point for the development of new antibiofilm agents

Cocrystallization of diastereomers in the series of 2(5H)-furanone bis-thioethers based on 1,2-phenylenedimethanethiol

© 2016, Springer Science+Business Media New York.Crystallization of diastereomeric mixtures of 2(5H)-furanone bis-thioethers, in the molecules of which two unsaturated γ-lactone rings are bound by 1,2-phenylenedimethanethiol bridge through their carbon atoms C(4), was studied. A rare case of cocrystallization of meso- and d,l-diastereomers for bis-thioethers with the small-size methoxy or hydroxy substituents at the asymmetric carbon atom was observed

Peculiarities of microwave discharge between a copper pin electrode and technical water

© 2014, Pleiades Publishing, Ltd. Some experimental results on burning of the microwave discharge between a copper pin electrode and technical water, in air, are presented within the ranges of the voltage U = 28–75 kV, the frequency f = 40–100 MHz, and the interelectrode space l = 2–20 mm. The essential influence of the pulse repetition frequency and the interelectrode space on the development, the shape, and the structure of the microwave discharge between the copper electrode and the technical water is revealed. Also the transition of the weakly glowing microdischarges inside the microwave discharge into the multichannel spark discharge is revealed. A temperature decrease below room temperature in the interelectrode gap of the microwave discharge with the technical water is discovered

Thio derivatives of 2(5H)-furanone as inhibitors against Bacillus subtilis biofilms

© 2015 Park-media, Ltd. Gram-positive bacteria cause a wide spectrum of infectious diseases, including nosocomial infections. While in the biofilm, bacteria exhibit increased resistance to antibiotics and the human immune system, causing difficulties in treatment. Thus, the development of biofilm formation inhibitors is a great challenge in pharmacology. The gram-positive bacterium Bacillus subtilis is widely used as a model organism for studying biofilm formation. Here, we report on the effect of new synthesized 2(5H)-furanones on the biofilm formation by B.subtilis cells. Among 57 compounds tested, sulfur-containing derivatives of 2(5H)-furanone (F12, F15, and F94) repressed biofilm formation at a concentration of 10 μg/ml. Derivatives F12 and F94 were found to inhibit the biosynthesis of GFP from the promoter of the eps operon encoding genes of the biofilm exopolysaccharide synthesis (EPS). Using the differential fluorescence staining of alive/dead cells, we demonstrated an increased bacterial sensitivity to antibiotics (kanamycin and chloramphenicol) in the presence of F12, F15, and F94, with F12 being the most efficient one. The derivative F15 was capable of disrupting an already formed biofilm and thereby increasing the efficiency of antibiotics

Inhibition of biofilm formation in Bacillus subtilis by new halogenated furanones

© 2015 Japan Antibiotics Research Association All rights reserved. Gram-positive bacteria can cause various infections including hospital-acquired infections. While in the biofilm, the resistance of bacteria to both antibiotics and the human immune system is increased causing difficulties in the treatment. Bacillus subtilis, a non-pathogenic Gram-positive bacterium, is widely used as a model organism for studying biofilm formation. Here we investigated the effect of novel synthesized chloro- and bromo-containing 2(5H)-furanones on biofilm formation by B. subtilis. Mucobromic acid (3,4-dibromo-5-hydroxy-2(5H)-furanone) and the two derivatives of mucochloric acid (3,4-dichloro-5-hydroxy-2(5H)-furanone) - F8 and F12 - were found to inhibit the growth and to efficiently prevent biofilm formation by B. subtilis. Along with the low production of polysaccharide matrix and repression of the eps operon, strong repression of biofilm-related yqxM also occurred in the presence of furanones. Therefore, our data confirm that furanones affect significantly the regulatory pathway(s) leading to biofilm formation. We propose that the global regulator, Spo0A, is one of the potential putative cellular targets for these compounds