Plastic pollution on the world's coral reefs.

Coral reefs are losing the capacity to sustain their biological functions1. In addition to other well-known stressors, such as climatic change and overfishing1, plastic pollution is an emerging threat to coral reefs, spreading throughout reef food webs2, and increasing disease transmission and structural damage to reef organisms3. Although recognized as a global concern4, the distribution and quantity of plastics trapped in the world's coral reefs remains uncertain3. Here we survey 84 shallow and deep coral ecosystems at 25 locations across the Pacific, Atlantic and Indian ocean basins for anthropogenic macrodebris (pollution by human-generated objects larger than 5 centimetres, including plastics), performing 1,231 transects. Our results show anthropogenic debris in 77 out of the 84 reefs surveyed, including in some of Earth's most remote and near-pristine reefs, such as in uninhabited central Pacific atolls. Macroplastics represent 88% of the anthropogenic debris, and, like other debris types, peak in deeper reefs (mesophotic zones at 30-150 metres depth), with fishing activities as the main source of plastics in most areas. These findings contrast with the global pattern observed in other nearshore marine ecosystems, where macroplastic densities decrease with depth and are dominated by consumer items5. As the world moves towards a global treaty to tackle plastic pollution6, understanding its distribution and drivers provides key information to help to design the strategies needed to address this ubiquitous threat.

Mesophotic ecosystems at Fernando de Noronha Archipelago, Brazil (South-western Atlantic), reveal unique ichthyofauna and need for conservation

Abstract Although several studies on the ichthyofauna of the Fernando de Noronha Archipelago have been carried out, its mesophotic fish diversity has never been surveyed before. Here we used SCUBA and technical rebreather diving, baited remote underwater videos and remotely operated vehicle to record shallow (≤ 30 m depth) and mesophotic (31 to 150 m depth) fishes. Nineteen fish species belonging to 14 families are reported here as new records, representing an increase of 8.2% in marine fish richness for the region, which now has a total of 250 species and 77 families. These new records include four potential new species and highlight the importance of surveying mesophotic ecosystems, even in well studied sites. Our results also emphasize the need for protection and attention to the unique ichthyofauna found at mesophotic depths.(AU)

Resumo Apesar de muitos estudos sobre a ictiofauna do Arquipélago de Fernando de Noronha terem sido realizados, sua diversidade de peixes mesofóticos nunca foi estudada antes. Neste estudo utilizamos mergulho autônomo e mergulho técnico, vídeos subaquáticos remotos com isca e veículo operado remotamente para registrar peixes de ecossistemas rasos (≤ 30 m de profundidade) e mesofóticos (31 a 150 m de profundidade). Dezenove espécies de peixes pertencentes a 14 famílias são apresentadas aqui como novos registros, representando um aumento de 8,2% na riqueza de peixes marinhos da região, que agora possui um total de 250 espécies e 77 famílias. Esses novos registros incluem quatro prováveis novas espécies e reforçam a importância de estudos em ecossistemas mesofóticos. Nossos resultados também enfatizam a necessidade de proteção e atenção à essa ictiofauna única encontrada nesses ecossistemas profundos.(AU)

A habitat-based approach to predict impacts of marine protected areas on fishers.

Although marine protected areas can simultaneously contribute to biodiversity conservation and fisheries management, the global network is biased toward particular ecosystem types because they have been established primarily in an ad hoc fashion. The optimization of trade-offs between biodiversity benefits and socioeconomic values increases success of protected areas and minimizes enforcement costs in the long run, but it is often neglected in marine spatial planning (MSP). Although the acquisition of spatially explicit socioeconomic data is perceived as a costly or secondary step in MSP, it is critical to account for lost opportunities by people whose activities will be restricted, especially fishers. We developed an easily reproduced habitat-based approach to estimate the spatial distribution of opportunity cost to fishers in data-poor regions. We assumed the most accessible areas have higher economic and conservation values than less accessible areas and their designation as no-take zones represents a loss of fishing opportunities. We estimated potential distribution of fishing resources from bathymetric ranges and benthic habitat distribution and the relative importance of the different resources for each port of total catches, revenues, and stakeholder perception. In our model, we combined different cost layers to produce a comprehensive cost layer so that we could evaluate of trade-offs. Our approach directly supports conservation planning, can be applied generally, and is expected to facilitate stakeholder input and community acceptance of conservation.

Atheroprotective action of a modified organoselenium compound: in vitro evidence.

Oxidation of low-density lipoprotein (LDL) has been strongly suggested to play a significant role in the pathogenesis of atherosclerosis. Thus, reducing LDL oxidation is a potential approach to decrease the risk of the atherosclerosis. Organoselenium compounds have demonstrated promising atheroprotective properties in experimental models. Herein, we tested the in vitro atheroprotective capability of a modified organoselenium compound, Compound HBD, in protecting isolated LDL from oxidation as well as foam cells formation. Moreover, the glutathione peroxidase (GPx)-like activity of Compound HBD was analyzed in order to explore the mechanisms related to the above-mentioned protective effects. The Compound HBD in a concentration-dependent manner reduced the Cu2+-induced formation of conjugated dienes. The protein portion from LDL were also protected from Cu2+-induced oxidation. Furthermore, the Compound HBD efficiently decreased the foam cell formation in J774 macrophage cells exposed to oxidized LDL. We found that the atheroprotective effects of this compound can be, at least in part, related to its GPx-like activity. Our findings demonstrated an impressive effect of Compound HBD against LDL-induced toxicity, a further in vivo study to investigate in more detail the antioxidant and antiatherogenic effects of this compound could be considered.

An extensive reef system at the Amazon River mouth.

Large rivers create major gaps in reef distribution along tropical shelves. The Amazon River represents 20% of the global riverine discharge to the ocean, generating up to a 1.3 × 10(6)-km(2) plume, and extensive muddy bottoms in the equatorial margin of South America. As a result, a wide area of the tropical North Atlantic is heavily affected in terms of salinity, pH, light penetration, and sedimentation. Such unfavorable conditions were thought to imprint a major gap in Western Atlantic reefs. We present an extensive carbonate system off the Amazon mouth, underneath the river plume. Significant carbonate sedimentation occurred during lowstand sea level, and still occurs in the outer shelf, resulting in complex hard-bottom topography. A permanent near-bottom wedge of ocean water, together with the seasonal nature of the plume's eastward retroflection, conditions the existence of this extensive (~9500 km(2)) hard-bottom mosaic. The Amazon reefs transition from accretive to erosional structures and encompass extensive rhodolith beds. Carbonate structures function as a connectivity corridor for wide depth-ranging reef-associated species, being heavily colonized by large sponges and other structure-forming filter feeders that dwell under low light and high levels of particulates. The oxycline between the plume and subplume is associated with chemoautotrophic and anaerobic microbial metabolisms. The system described here provides several insights about the responses of tropical reefs to suboptimal and marginal reef-building conditions, which are accelerating worldwide due to global changes.

Transcriptional activity, chromosomal distribution and expression effects of transposable elements in Coffea genomes.

Plant genomes are massively invaded by transposable elements (TEs), many of which are located near host genes and can thus impact gene expression. In flowering plants, TE expression can be activated (de-repressed) under certain stressful conditions, both biotic and abiotic, as well as by genome stress caused by hybridization. In this study, we examined the effects of these stress agents on TE expression in two diploid species of coffee, Coffea canephora and C. eugenioides, and their allotetraploid hybrid C. arabica. We also explored the relationship of TE repression mechanisms to host gene regulation via the effects of exonized TE sequences. Similar to what has been seen for other plants, overall TE expression levels are low in Coffea plant cultivars, consistent with the existence of effective TE repression mechanisms. TE expression patterns are highly dynamic across the species and conditions assayed here are unrelated to their classification at the level of TE class or family. In contrast to previous results, cell culture conditions per se do not lead to the de-repression of TE expression in C. arabica. Results obtained here indicate that differing plant drought stress levels relate strongly to TE repression mechanisms. TEs tend to be expressed at significantly higher levels in non-irrigated samples for the drought tolerant cultivars but in drought sensitive cultivars the opposite pattern was shown with irrigated samples showing significantly higher TE expression. Thus, TE genome repression mechanisms may be finely tuned to the ideal growth and/or regulatory conditions of the specific plant cultivars in which they are active. Analysis of TE expression levels in cell culture conditions underscored the importance of nonsense-mediated mRNA decay (NMD) pathways in the repression of Coffea TEs. These same NMD mechanisms can also regulate plant host gene expression via the repression of genes that bear exonized TE sequences.