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The study of two-phase immiscible flow in porous media using electrokinetics is important in different fields including the remediation of hydrocarbon contaminated soils and enhanced oil recovery. While electrokinetic technology has been traditionally used for treatment and decontamination of hydrocarbon polluted sites, electrically enhanced oil recovery (EEOR) is relatively new. Although a few laboratory and field experiments have investigated the potential promise of the EEOR method, further investigation is necessary to better understand the fundamentals and the importance of different parameters/processes that affect the oil production in this method. This study presents a numerical investigation of two-phase flow in EEOR method in an attempt to provide insight into the feasibility of, and the important parameters involved in this method. A sensitivity analysis is performed on important parameters involved in EEOR combined with water flooding. Most of the investigated reservoir and operational parameters were found to be significant and critical to the transport phenomena controlling the oil production. In addition, the results showed that the applied electrical gradient involved in EEOR combined with water flooding contributes to a small increase in oil production.

The association of temporomandibular joint (TMJ) disorders with aural symptoms, such as tinnitus, otic fullness, and subjective decrease of hearing acuity, is a well-established clinical observation. Although several hypotheses have been made about the otic-conductive origin of these complaints, conventional 226-Hz tympanometry has failed to demonstrate any middle ear abnormalities. The aim of this study was to evaluate patients with TMJ disorders with multiple frequency tympanometry (MFT).

Objective:To assess the outcomes of neonatal hearing screening with regard to the final diagnosis in a very large number of newborns and investigate related strengths and weaknesses of the program.

The fatty acids and the total fat content of eight species of Mediterranean fish (Scomber japonicus, Boops boops, Mullus barbatus, Mullus surm uletus, Merluccius merluccius, Pagelius erythrinus, Pagrus pagrus, Sparus aurata — see Appendix 1) commonly consumed in this area were analysed. Six of the fishes were caught from the Kritiko pelagos, and the other two, the Sparus aurata and the Pagrus pagrus, were donated from the fishes cultured at the Institute of Marine Biology of Crete. The GC chromatography of the fatty acids showed the n-3 to range from 12.6 to 28.3% of the observed acids. The n-6/n-3 ratio of fatty acids was found to be 0.2-0.7, and the saturated fatty acids range from 28.0 to 33.2%. These results demonstrate that the eight species of fish studied from the Mediterranean sea are a good source of n-3 fatty acids.

Ten brands of margarines from the Greek market were analysed. The fatty acid (FA) composition was estimated by using gas liquid chromatography (GLC) with a capillary column. A sample of Cretan olive oil was used as a control. The brands of the same margarines were bought and analysed twice (June and October 1991) in order to observe differences between batches. During the second part of the study it was possible to distinguish between the cis and trans isomers of the unsaturated fatty acids. The ratios of polyunsaturated/saturated, monounsaturated/polyunsaturated and saturated/monounsaturated (P/S, M/P, S/M) fatty acids were calculated as well as the ω-6/ω-3 ratio. Four brands contained at least 40% saturated fatty acids. Trans double bonds were additionally regarded as simple bonds and the conventional ratios were recalculated. The amount of the 18:1 trans fatty acid ranged from 5.40 to 9.54% and that of cis-trans and trans-cis 18:2 fatty acids from 0.40 to 3.65%. The 18:2 trans-trans fatty acids ranged from 0 to 1.23%. Food consumption surveys in Crete showed that in selective population samples, margarine consumption was approximately 9 g/day for children and 2 g/day for adults. The analysis of fatty acids in adipose tissue of 70 Cretan lawyers showed 0.90 ± 0.25% (0.46-1.67) for 4 trans isomers of oleic acid and 0.14 ± 0.06% (0.05-0.31) and 0.04 ± 0.01% (0.02-0.06) for trans-cis and cis-trans isomers of linoleic acid respectively. Although margarine consumption in Crete is still low, trans fatty acids content is reflected in the adipose fatty acid composition. The industry must consider the potential health risks that consumption of such margarines will have on the population, and they must try to improve their products.

Hybrid, organic–inorganic, biocidal films exhibiting polishing properties were developed as effective long-lasting antimicrobial surface coatings. The films were prepared using cationically modified chitosan, synthesized by the reaction with 3-bromo-N,N,N-trimethylpropan-1-aminium bromide, to introduce permanent biocidal quaternary ammonium salt (QAS) groups along the polymer backbone and were cross-linked by a novel, pH-cleavable acetal cross-linker, which allowed polishing the hybrid coatings with the solution pH. TiO2nanoparticles, modified with reduced graphene oxide (rGO) sheets, to narrow their band gap energy value and shift their photocatalytic activity in the visible light regime, were introduced within the polymer film to enhance its antibacterial activity. The hybrid coatings exhibited an effective biocidal activity in the dark (∼2 Log and ∼3 Log reduction for Gram-negative and Gram-positive bacteria, respectively), when only the QAS sites interacted with the bacteria membrane, and an excellent biocidal action upon visible-light irradiation (∼5 Log and ∼6 Log reduction for Gram-negative and Gram-positive bacteria, respectively) due to the synergistic antimicrobial effect of the QAS moieties and the rGO-modified TiO2nanoparticles. The gradual decrease in the film thickness, upon immersion of the coatings in mildly basic (pH 8), neutral (pH 7), and acidic (pH 6) media, reaching 10, 20, and 70% reduction, respectively, after 60 days of immersion time, confirmed the polishing behavior of the films, whereas their effective antimicrobial action was retained. The biocompatibility of the hybrid films was verified in human cell culture studies. The proposed approach enables the facile development of highly functional coatings, combining biocompatibility and bactericidal action with a “kill and self-clean” mechanism that allows the regeneration of the outer surface of the coating leading to a strong and prolonged antimicrobial action.