Physical behavior of membrane blends of poly(vinyl alcohol) (PVA) doped with different weight percentage (wt %) of algal glycerol is reported. Solid-state PVA/glycerol membranes were prepared by the solution casting method. Electrical impedance measurements were conducted to test the effect of varying the percentage of glycerol on the conductivity of the membranes. The measurements were made in the frequency and temperature ranges 1 Hz-1 MHz and 303-423 K, respectively. It was observed that the ionic conductivity increased with the increase of glycerol concentration as well as temperature. The thermal properties of the films were characterized. It was found that the thermal properties, particularly the melting point (T m ), for PVA blends exhibit a reduced value proportional to the algal glycerol content. Fourier transform infrared spectroscopy was utilized to evaluate the interactions between the glycerol and PVA.

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Genetic variability among three species of red sea fishes (Lethrinus borbonicus, Siganus rivulatus and Mulloidichthys flavolineatus) were determined to evaluate the effect of petroleum oil component pollutions on the fishes using Inter-simple sequence repeats (ISSRs) and sodium dodecyl sulfate-polyacrlamide gel electrophoresis (SDS-PAGE) markers. According to ISSR analysis of DNA, nineteen (19) ISSR primers generated a total of 465 bands with an average 24.5 bands per primer. Analyses of SDS-PAGE protein, 137 bands were identified variant bands from 44, 43 and 50 in sample Lethrinus borbonicus, Siganus rivulatus and Mulloidichthys flavolineatus respectively. Analysis of SDS-PAGE protein provided more precise information concerning of the effect of petroleum oil components on protein subunits and genetic variation in Siganus rivulatus species than ISSR-PCR of DNA. Whereas ISSR technique showed more polymorphism or relatively a close to the percentage of SDS-PAGE result among the tow species Lethrinus borbonicus and Mulloidichthys flavolineatus compared to there controls. A remarkable result from this study was identifying that petroleum oil components pollution have distinct effect in genetic structure of fishes and lead to disappear of some protein subunits or appear new some protein subunits in fish muscle tissues.

Among Oniscidea suborder, Porcellionidae is the richest and widely-distributed Family. However, the phylogeny investigations of its taxa were not completely covered. Therefore, a phylogeographic population and genetic diversity study was carried out here on two cosmopolitan terrestrial isopod species (Porcellionides pruinosus and Porcellio laevis) by utilizing mitochondrial cytochrome c oxidase subunit 1 (CO1) gene. The sequencing of CO1 among the understudied populations showed nucleotide length ranged from 646 base pairs (bp) to 660 bp. The average contents of nucleotide bases A+T in Porcellionides pruinosus and Porcellio laevis were 63.8% and 63.3%, respectively. Also, the average content of pyrimidines (C+T) bases in Porcellionides pruinosus and Porcellio laevis was higher than the purines content. Nucleotide bases A+T contents were higher than nucleotide bases C+G contents in all populations. The pairwise genetic distances among the understudied Porcellionides pruinosus populations ranged from 0.000 to 0.002. The most related populations were in Qeft and Deshna, where the genetic distance was 0.000. The pairwise genetic distances among the understudied populations of Porcellio laevis ranged from 0.017 to 0.033. The most related populations were in Qeft and Hurghada, where the genetic distance was 0.017. Furthermore, Porcellio laevis populations need more investigations, as it seems to be polyphyletic comparing to Porcellionides pruinosus populations.