Drinfeld twist and symmetric Bethe vectors of the open XYZ chain with non-diagonal boundary terms

With the help of the Drinfeld twist or factorizing F-matrix for the eight-vertex solid-on-solid (SOS) model, we find that in the F-basis provided by the twist the two sets of pseudo-particle creation operators simultaneously take completely symmetric and polarization free form. This allows us to obtain the explicit and completely symmetric expressions of the two sets of Bethe states of the model.Comment: Latex file, 25 page

27 years of benthic and coral community dynamics on turbid, highly urbanised reefs off Singapore

Coral cover on reefs is declining globally due to coastal development, overfishing and climate change. Reefs isolated from direct human influence can recover from natural acute disturbances, but little is known about long term recovery of reefs experiencing chronic human disturbances. Here we investigate responses to acute bleaching disturbances on turbid reefs off Singapore, at two depths over a period of 27 years. Coral cover declined and there were marked changes in coral and benthic community structure during the first decade of monitoring at both depths. At shallower reef crest sites (3–4 m), benthic community structure recovered towards pre-disturbance states within a decade. In contrast, there was a net decline in coral cover and continuing shifts in community structure at deeper reef slope sites (6–7 m). There was no evidence of phase shifts to macroalgal dominance but coral habitats at deeper sites were replaced by unstable substrata such as fine sediments and rubble. The persistence of coral dominance at chronically disturbed shallow sites is likely due to an abundance of coral taxa which are tolerant to environmental stress. In addition, high turbidity may interact antagonistically with other disturbances to reduce the impact of thermal stress and limit macroalgal growth rates

Impacts of Sediments on Coral Energetics: Partitioning the Effects of Turbidity and Settling Particles

Sediment loads have long been known to be deleterious to corals, but the effects of turbidity and settling particles have not previously been partitioned. This study provides a novel approach using inert silicon carbide powder to partition and quantify the mechanical effects of sediment settling versus reduced light under a chronically high sedimentary regime on two turbid water corals commonly found in Singapore (Galaxea fascicularis and Goniopora somaliensis). Coral fragmentswere evenly distributed among three treatments: an open control (30% ambient PAR), a shaded control (15% ambient PAR) and sediment treatment (15% ambient PAR; 26.4 mg cm22 day21). The rate of photosynthesis and respiration, and the dark-adapted quantum yield were measured once a week for four weeks. By week four, the photosynthesis to respiration ratio (P/R ratio) and the photosynthetic yield (Fv/Fm) had fallen by 14% and 3–17% respectively in the shaded control,contrasting with corals exposed to sediments whose P/R ratio and yield had declined by 21% and 18–34% respectively. The differences in rates between the shaded control and the sediment treatment were attributed to the mechanical effects of sediment deposition. The physiological response to sediment stress differed between species with G. fascicularis experiencing a greater decline in the net photosynthetic yield (13%) than G. somaliensis (9.5%), but a smaller increase in the respiration rates (G. fascicularis = 9.9%, G. somaliensis = 14.2%). These different physiological responses were attributed, in part, to coral morphology and highlighted key physiological processes that drive species distribution along high to low turbidity and depositional gradients

Urban coral reefs: Degradation and resilience of hard coral assemblages in coastal cities of East and Southeast Asia

© 2018 The Author(s) Given predicted increases in urbanization in tropical and subtropical regions, understanding the processes shaping urban coral reefs may be essential for anticipating future conservation challenges. We used a case study approach to identify unifying patterns of urban coral reefs and clarify the effects of urbanization on hard coral assemblages. Data were compiled from 11 cities throughout East and Southeast Asia, with particular focus on Singapore, Jakarta, Hong Kong, and Naha (Okinawa). Our review highlights several key characteristics of urban coral reefs, including “reef compression” (a decline in bathymetric range with increasing turbidity and decreasing water clarity over time and relative to shore), dominance by domed coral growth forms and low reef complexity, variable city-specific inshore-offshore gradients, early declines in coral cover with recent fluctuating periods of acute impacts and rapid recovery, and colonization of urban infrastructure by hard corals. We present hypotheses for urban reef community dynamics and discuss potential of ecological engineering for corals in urban areas

Communicating a Marine Protected Area Through the Local Press: The Case of the National Marine Park of Alonissos, Northern Sporades, Greece

Local distrust for Marine Protected Area (MPA) managers is emerging as an important factor obstructing the fulfillment of MPA objectives, and, thus, there is a need to develop a means of enhancing relationship building between MPA managers and local people. We used the National Marine Park of Alonissos, Northern Sporades (NMPANS), Greece, as a relevant case-study to investigate whether the local print media's framing of the marine park and its management affected locals' attitudes. We conducted a longitudinal review of local newspaper articles pertaining to the NMPANS during 1980-2008, and we conducted telephone interviews with local people. We found that salience of the NMPANS in the local print media remained limited and sporadic, the main stakeholder remained the centralized public sector, and the regional print media was rather detached, moderate, and largely supportive of the NMPANS throughout 1980-2008. The progression of the management periods of the NMPANS, however, was accompanied by increased importance of the NMPANS, increased deviance from conservation as the chief objective of the NMPANS's establishment, a shift from presenting facts to presenting reactions, and a shift from a positive to a mixed image of the NMPANS. Locals who relied on newspapers for local news were better informed about the NMPANS, more likely to accept the NMPANS, and more likely to participate in meetings regarding the NMPANS regardless of gender, age, and occupation than those who did not rely on newspapers. The local print media may be utilized as a free-choice learning vehicle to enhance the value of an MPA among local people and to enhance the development of trust between park managers and locals through a proactive, empowering, and cognitive media strategy

The functional characterisation of the human homologue of Drosophila Ariadne (HHARI)

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Fishery Exploitation and Stock Assessment of the Endangered Nassau Grouper, Epinephelus Striatus (Actinopterygii: Perciformes: Serranidae), in the Turks and Caicos Islands

The Nassau grouper, Epinephelus striatus (Bloch, 1792), is an endangered species that has been historically overexploited in numerous fisheries throughout its range in the Caribbean and tropical West Atlantic. Data relating fishery exploitation levels to stock abundance of the species are deficient, and protective regulations for the Nassau grouper are yet to be implemented in the Turks and Caicos Islands (TCI). The goal of this study was to conduct a stock assessment and evaluate the exploitation status of the Nassau grouper in the TCI. Materials and methods. Calibrated length cohort analysis was applied to published fisheries data on Nassau grouper landings in the TCI. The total lengths of Nassau groupers among the catches of spearfishers, lobster trappers, and deep sea fishers on the island of South Caicos during 2006 and 2008 were used with estimates of growth, natural mortality, and total annual landings to derive exploitation benchmarks. Results. The TCI stock experienced low to moderate fishing mortality (0.28, 0.18) and exploitation rates (0.49, 0.38) during the period of the study (2006, 2008). However, 21.2%-64.4% of all landings were reproductively immature. Spearfishing appeared to contribute most to fishing mortality relative to the use of lobster traps or hydraulic reels along bank drop-offs. Conclusion. In comparison with available fisheries data for the wider Caribbean, the results reveal the TCI as one of the remaining sites, in addition to the Bahamas, with a substantial Nassau grouper stock. In light of increasing development and tourism in the TCI, continued monitoring is essential to maintain sustainable harvesting practices

Abiotic and biotic patterns across Mediterranean coastal wetland systems, North East Aegean, Greece

1 - Coastal wetlands are regarded as transitional ecosystems regulating fluxes of materials and energy between the land and the sea and are protected habitats under the NATURA 2000 European network of protected areas. Description of spatial heterogeneity in abiotic and biotic constituents of coastal wetland systems is a prerequisite for the establishment of long-term monitoring programs and a first step in elucidating their functional role in the landscape; both of particular significance to management. Spatial variability of water and substratum physicochemical variables and of substratum macroinvertebrate fauna composition and abundance across five sea-coastal wetland-land systems, Kalloni bay, Lesvos Island, Greece, were quantified during the growing season of 2005. 2 - The studied coastal wetlands develop on an alluvial flat plain of mineral soils as indicated by low values of percent organic matter, circumneutral pH, and high values of bulk density. Trends in physicochemical variables of substratum varied among the five coastal wetland systems studied even when the same variable was examined. Canonical discriminant analysis indicated that the most important substratum physicochemical variable in differentiating among the sea-wetland-land units of the studied gradients was electrical conductivity (salt influence) in four out of the five coastal wetland systems. Total nitrogen concentration of substratum was the only variable among the ones studied which was related positively either with total phosphorus concentration or/and percent organic matter of substratum in all wetland systems studied; the highest values occurred where vegetation was present. 3 - Distribution and abundance of substratum macroinvertebrate taxa across the sea-wetland-land gradients studied reflected the interaction between the marine and terrestrial environment. Gasteropoda, bivalvia and schaphopoda were found in higher abundances at sea and sea-influenced stations, which gradually decreased towards the land. On the other hand, insecta appeared at stations further away from the shore and their abundance progressively increased towards land. Gasteropoda and insecta were the taxa responsible for the identification of at least three clusters of stations across all five coastal systems studied. Two clusters contained clearly "terrestrially-influenced" or "sea-influenced" stations while intermediate clusters contained stations with varying degree of salt influence. 4 - Distribution and abundance of gasteropoda and insecta, however, were found to be directly related to nutrient status and not to electrical conductivity of substratum