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Optical monitoring technologies can be used to monitor membrane fouling in real-time and online with the in-situ, fast and nondestructive advantages, which are of great significance for the in-depth understanding of membrane fouling and the optimization of fouling control strategies. In this paper, several kinds of optical real-time monitoring technologies for membrane fouling that had been studied and developed rapidly in recent years were reviewed, including microscopic imaging techniques such as direct observation through membrane, optical coherence tomography and laser confocal microscopy, molecular spectroscopies such as excitation-emission matrix and Raman spectroscopy, and particle image velocimetry. The principles, the typical applications in fouling characterization of these techniques and the derivative techniques were described comprehensively, and the advantages and disadvantages of each technique were analyzed from the aspects of monitoring area and foulant information provided. Finally, the future development direction of the optical monitoring technologies was put forward, which would promote the application of these technologies in the membrane water treatment industries.

Objective To investigate the method for establishing an immortalized mouse corneal epithelial cell line, and to identify the stability of its phenotype. Methods Primary mouse corneal epithelial cells were extracted and transfected with Simian Vacuolating Virus 40 Large T Antigen (SV40-LT) lentivirus to establish an immortalized cell line. HE staining and immunofluorescent staining were used to identify the phenotypes and markers (K12, Pax6, Ki-67) of corneal epithelium. Primary cor-neal epithelial cells were extracted to identify K14 protein in corneal epithelial cell layer, and bright field observation was performed to evaluate cell morphological characteristics. Several markers (K12, Pax6, Ki-67, ABCG2, K14) were identified for P1 and P8 cells after transfection. Crystal violet staining was used to observe the colony-formation ability of P1 and P8 cells after transfection. Results Mouse corneal epithelium was stained positive for K12, Pax6 and Ki-67, while the P1 and P8 generations of mouse cor-neal epithelial cells were stained positive for K12, Pax6, Ki-67, K14, and ABCG2; there were no significant differences in the positive rates of the above markers (P>0.05). There was no significant difference in colony-formation ability between P1 and P8 cells (P>0.05). Conclusion The immortalized mouse corneal epithelial cell line is successfully established by transfection with SV40-LT lentivirus, which has stable phenotype and proliferation.

Ixodes (Ixodes) mojavensis, n. sp. (Acari: Ixodidae), is described from all parasitic stages collected from the endangered vole Microtus californicus scirpensis Bailey, 1900 (Rodentia: Cricetidae), Mus musculus L. 1758 (Rodentia: Muridae), and Reithrodontomys megalotis (Baird; 1857) (Rodentia: Cricetidae) in the Amargosa Valley of California. When first collected in 2014, this tick was tentatively identified as Ixodes minor Neumann, 1902 because the nucleotide similarity between its 16S rDNA sequence and a homologous GenBank sequence from an I. minor from the eastern U.S. was 99.51%. Nevertheless, adults of I. mojavensis differ morphologically from I. minor by hypostomal dentition, absence of a spur on palpal segment I, and punctation patterns; nymphs by the shapes of basis capituli, auriculae, cervical grooves and external files of hypostomal denticles; and larvae by the length of idiosomal setae and hypostomal dentition. DNA sequencing of fragments of 4 different genes, 12S rDNA, 16S rDNA, cytochrome c oxidase subunit I (COI), and intergenic transcribed spacer 2 (ITS2) of I. mojavensis and of closely related species of Ixodes shows that the mitochondrial gene sequences of the new tick species are almost identical to the I. minor homologous genes. Phylogenetically, the two species do not cluster in mutually exclusive monophyletic clades. However, ITS2 sequences of I. mojavensis and I. minor diverge deeply (≥ 5.74% maximum likelihood divergence) and are as different as homologous genes from other recognized species. The discrepancy between the two sets of genes is suggestive of past mitochondrial introgression or incomplete mitochondrial lineage sorting.

Kefir is a fermented dairy beverage produced by using natural microbiota which mainly contains specific microbial communities such as lactic acid bacteria, yeast and acetic acid bacteria, and it has good flavor and health beneficial functions. However, the formation mechanism of kefir grains is not clear at present, and it is generally believed that the formation of kefir grains is based on bacterial biofilm as the precursor. This paper reviews the microbial diversity of kefir from different regions and the effects of microorganisms in kefir grains on the function and flavor of fermented milk, as well as the microbial interactions and succession during kefir fermentation. The role of biofilm formation in kefir grain formation is also described in order to provide some references for future research on the formation mechanism of kefir grains.