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This paper presents an experimental investigation revisiting the anisotropic stress-strain-strength behaviour of geomaterials in drained monotonic shear using hollow cylinder apparatus. The test programme has been designed to cover the effect of material anisotropy, preshearing, material density and intermediate principal stress on the behaviour of Leighton Buzzard sand. Experiments have also been performed on glass beads to understand the effect of particle shape. This paper explains phenomenological observations based on recently acquired understanding in micromechanics, with attention focused on strength anisotropy and deformation non-coaxiality, i.e. non-coincidence between the principal stress direction and the principal strain rate direction. The test results demonstrate that the effects of initial anisotropy produced during sample preparation are significant. The stress-strain-strength behaviour of the specimen shows strong dependence on the principal stress direction. Preloading history, material density and particle shape are also found to be influential. In particular, it was found that non-coaxiality is more significant in presheared specimens. The observations on the strength anisotropy and deformation non-coaxiality were explained based on the stress-force-fabric relationship. It was observed that intermediate principal stress parameter b(b = (r 2-r 3)/ (r 1-r 3)) has a significant effect on the non-coaxiality of sand. The lower the b-value, the higher the degree of noncoaxiality is induced. Visual inspection of shear band formed at the end of HCA testing has also been presented. The inclinations of the shear bands at different loading directions can be predicted well by taking account of the relative direction of the mobilized planes to the bedding plane.

The cosmopolitan red algal genus Pyropia sensu lato is the most speciose of the bladed Bangiales genera. In a major revision of the Bangiales, Pyropia was resurrected from Porphyra, although there was evidence at the time that species of Pyropia could be separated into several genera. Subsequent global phylogenetic analyses continued to resolve species assigned to Pyropia into several major clades with strong support, and the latest biogeographic analyses indicated that species distribution was also a pointer to the underlying phylogeny of Pyropia sensu lato. Therefore, in the present study, we have redefined the genus Pyropia, resurrected Porphyrella, and proposed four new genera: Calidia, Neoporphyra, Neopyropia, and Uedaea. Based on a molecular phylogenetic study of the bladed Bangiales of China, a species which did not match any known taxa was resolved in the new genus Calidia. The species, Calidia pseudolobata sp. nov., is described based on both morphological and molecular data. Molecular sequence data for rbcL, 18S, and COI‐5P were amplified for 15 samples in the present study. All the obtained rbcL sequences were identical to each other except for one (LYCN117) with one base pair difference. Two haplotypes of 18S (V9 region) were observed with one base pair difference (C/T30). All the obtained COI‐5P sequences were identical. Morphological comparisons were conducted not only with species in Calidia, but also with generically uncertain species currently assigned to Porphyra.

Carotene hydroxylases catalyze the hydroxylation of a-and b-carotene hydrocarbons into xanthophylls. In red algae, b-carotene is a ubiquitously distributed carotenoid, and hydroxylated carotenoids such as zeaxanthin and lutein are also found. However, no enzyme with carotene hydroxylase activity had been previously identified in red algae. Here, we report the isolation of a gene encoding a cytochrome P450-type carotene hydroxylase (PuCHY1) from Porphyra umbilicalis, a red alga with an ancient origin. Sequence comparisons found PuCHY1 belongs to the CYP97B subfamily, which has members from different photosynthetic organisms ranging from red algae to land plants. Functional complementation in Escherichia coli suggested that PuCHY1 catalyzed the conversion from b-carotene to zeaxanthin. When we overexpressed PuCHY1 in the Arabidopsis thaliana chy2 mutant, pigment analysis showed a significant accumulation of hydroxylated carotenoids, including neoxanthin, violaxanthin, and lutein in the leaves of transgenic plants. These results confirmed a b-hydroxylation activity of PuCHY1, and also suggested a possible e-hydroxylation function. The pigment profile and gene expression analyses of the algal thallus under high-light stress suggested that P. umbilicalis is unlikely to operate a partial xanthophyll cycle for photoprotection.Keywords: Bangiales; carotene hydroxylase; carotenoid metabolism; CYP97B; cytochrome P450; Porphyra umbilicalis; red algae Citation: Yang LE, Huang XQ, Hang Y, Deng YY, Lu QQ, Lu S (2014) The P450-type carotene hydroxylase PuCHY1 from Porphyra suggested the evolution of carotenoid metabolism in red algae. J Integr Plant Biol 56: 902-915.

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Abstract:! This paper presents an experimental investigation revisiting the anisotropic stress-strainstrength behaviour of geomaterials in drained monotonic shear using Hollow Cylinder Apparatus. The test program has been designed to cover the effect of material anisotropy, preshearing, material density and intermediate principal stress on the behaviour of Leighton Buzzard sand. Experiments have also been performed on glass beads to understand the effect of particle shape. This paper explains phenomenological observations based on recently acquired understanding in micromechanics, with attention focused on strength anisotropy and deformation non-coaxiality, i.e., non-coincidence between the principal stress direction and the principal strain rate direction. The test results demonstrate that the effects of initial anisotropy produced during sample preparation is significant. The stress-strain-strength behaviour of the specimen shows strong dependence on the principal stress direction. Pre-loading history, material density and particle shape are also found to be influential. In particular, it was found that non-coaxiality is more significant in preloaded specimens. The observations on the strength anisotropy and deformation non-coaxiality were successfully explained based on the Stress-

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The cultivation of red seaweeds for food (nori), agar and carrageenans is the basis of a valuable industry. However, taxonomic knowledge of these cultivated seaweeds and their wild relatives has not kept pace with advances in molecular systematics despite the fundamental importance of being able to identify commercially important species and strains, discover cryptic and endemic taxa and recognize non-native species with potentially damaging diseases and epiphytes. This review focuses on molecular taxonomic advances in the cultivated red algae with the highest commercial value globally: Eucheuma, Kappaphycus, Porphyra sensu lato Porphyra/Pyropia and Gracilaria. All four genera are similarly taxonomically challenging. They are speciose, morphologically plastic, have poorly resolved species boundaries, and a stable taxonomy for each genus is yet to be achieved. Eucheuma and Kappaphycus are frequently misidentified and the molecular markers cox2-3 spacer, cox1 and RuBisCO spacer have helped to in understanding phylogenetic relationships, and identifying new species and haplotypes. In Porphyra sensu lato (Bangiales) species identification and phylogenetic relationships were highly problematic until a major taxonomic revision based on a two-gene phylogeny (18S and rbcL) resulted in nine genera of bladed species. Pyropia, with at least 89 species, three in nori cultivation, has potential for new commercial evaluation. The recently published Porphyra genome will aid the exploration of evolutionary relationships in this group. In Gracilaria sensu lato, earlier efforts to resolve species-level taxonomy and generic descriptions were superseded by application of molecular tools, including DNA sequences of the RuBisCO spacer, rbcL gene, 18S and the ITS region. Relationships between clades are now fairly well established, but much research on species and genera is still needed. Studies of these cultivated red algal genera highlight the need for a robust taxonomy, a more standardized approach to the molecular markers used and a comprehensive dataset for each representative species. RecentCurrent work on DNA-based species delimitation, the emergence of high throughput sequencing, multi-gene phylogenies and publication of whole genomes (e.g. Porphyra umbilicalis) and the large number of genomes in the pipeline (e.g. Gracilaria) is increasingly improving our understanding of phylogenomic relationships and hence a better understanding of species relationships. This knowledge, in turn, can then be applied to improving red seaweed aquaculture.