Redox conditions and heavy metals distribution in mangrove forests receiving effluents from shrimp farms (Teremba Bay, New Caledonia)

International audiencePurpose The mangroves of New Caledonia, in the south Pacific, act as a buffer between a lagoon of more than 20,000 km2 and the island, which is characterized by ultramafic rocks and lateritic soils that are exploited for their richness in heavy metals. We will provide a better understanding of the redox conditions, and of heavy metal distributions in mangroves receiving shrimp farm effluents. Materials and methods Samples were collected from four areas defined in terms of vegetation composition: a salt flat, an Avicennia marina forest, in which effluents are released; a Rhizophora stylosa forest, and a dead Rhizophora forest. They were collected during times of maximum effluent release. Some measurements on pore water were also done during a period without effluent. Cores (70 cm deep) were collected at low tide with an Eijkelkamp gouge auger, and pore waters were extracted using soil moisture samplers. Physico-chemical parameters (pH, Eh, salinity) were measured by directly inserting the probes into cores. Total nitrogen and total sulfur were also determined. The sedimentary organic content was studied using a Rock-Eval 6 pyrolysis. Finally, heavy metal concentrations were determined, both in the solid and the dissolved phases, using an HR-ICP-AES. Results and discussion The distribution of heavy metals in the core collected in the salt flat is mainly controlled, on the one hand, by the sedimentary organic content, and on the other hand, by the elevation of the area, which induced dessication. The release of effluent within the Avicennia stand induced anoxic conditions on the whole depth profile, while these conditions are suboxic without effluent release, probably inducing different metal speciation. The Rhizophora forests, located at 100 m from the release point, do not seem to show any impact from the effluent phase, as indicated by the redox profiles which show similar results with and without effluent release. Beneath these two stands, conditions are mainly anoxic and sulfidic, as a result of the decomposition of high organic matter content. Conclusions The release of effluent within the Avicennia stand, by modifying the length of waterlogging, clearly modifies the redox conditions. We suggest that the differences in redox conditions between the two periods modify the carrier phase of heavy metals, being mainly associated with sulfides during effluent release. Metals are thus less mobile, and consequently when mangrove receives effluents, they act as a sink for trace metals

Near-infrared Fourier transform room-temperature photoluminescence of erbium complexes

A modified Fourier transform (FT) Raman bench spectrometer designed for the detection of weak light emission in the 800–1700 nm wavelength region has been used to demonstrate the advantages of FT spectroscopy for measuring near-infrared photoluminescence spectra of lanthanide complexes with a good resolution and very good sensitivity. This apparatus has been tested with an ultraviolet laser source (325 nm) on three standard erbium complexes. The 4I13/24I15/2 emission of tris-(acetylacetonato) (1,10 phenanthroline) erbium [Er(acac)3(phen)], tris-(4,4,4,-trifluoro-1-(2 thenoyl)-1,3-butenedione) (1,10 phenanthroline) erbium [Er(TTFA)3(phen)] and tris(8-hydroxyquinolinato) erbium [Erq3] has thus been recorded in solution and in the solid state and compared with literature. ©2003 American Institute of Physics

Enhanced disengagement of auditory attention and phonological skills in action video gamers

Video games play a major role in the everyday life of children, teenagers, and adults. Several studies show that action video games (AVGs) improve visual attentional efficiency. AVGs also appear to improve reading speed and phonological skills in children with developmental dyslexia. These results have been linked to the intrinsic characteristics of AVGs, in which fast disengagement of multisensory attention allows for efficient extraction of relevant dynamic information, a skill that is crucially also involved in phonological and reading skills. We tested the hypothesis that AVG players demonstrate faster auditory attention disengagement in an auditory spatial cuing task, as well as better phonological and reading performance than non-players. We found that AVG players were faster in spatial localization of auditory targets and showed enhanced attentional disengagement as indexed by a smaller cuing effect. AVG players also showed better phonological decoding and working memory skills. Moreover, the beneficial effects of AVGs, as measured by faster attentional disengagement, were linked to better phonological and reading skills in adult AVG players. We suggest that a more efficient attentional disengagement - controlled by the posterior parietal cortex - induces enhanced multisensory processing in AVG players

<i>Mare Geneticum</i>: balancing governance of marine genetic resources in international waters

A fair and effective regime regulating benefit-sharing of marine genetic resources (MGR) in areas beyond national jurisdiction (ABNJ) must consider the inclusion of developing states, support scientific research and safeguard investments of the private sector. The present innovative proposal ensures a delicate balance through an approach based on open access, albeit with limitations. Access to MGR in ABNJ is facilitated, but conditional on the public release of collected samples and raw data. Adoption of the open access principle guarantees a powerful form of non-monetary benefit-sharing. The balance is maintained by the option for an extended embargo period, allowing samples and data to be kept confidential for a certain period, against payment to a biodiversity contribution fund. Monetary benefit-sharing, as a sector-negotiated percentage on revenue, could be imposed at the point of product commercialisation, and would offer a tangible payment system with a low transaction cost

Does the Visual Attention Span Play a Role in Reading in Arabic?

Published online: 16 Jan 2018.It is unclear whether the association between the visual attention (VA) span and reading differs across languages. Here we studied this relationship in Arabic, where the use of specific reading strategies depends on the amount of diacritics on words: reading vowelized and nonvowelized Arabic scripts favor sublexical and lexical strategies, respectively. We hypothesized that the size of the VA span and its association to reading would differ depending on individual “script preferences.” We compared children who were more proficient in reading fully vowelized Arabic than nonvowelized Arabic (VOW) to children for whom the opposite was true (NOVOW). NOVOW children showed a crowding effect in the VA span task, whereas VOW children did not. Moreover, the crowding in the VA span task correlated with the reading performance in the NOVOW group only. These results are discussed in light of individual differences on the use of reading strategies in Arabic.This report was made possible by a National Priorities Research Program award (Grant NPRP No. 6-378-5–035) from the Qatar National Research Fund (a member of The Qatar Foundation)

Environmental Impact Assessment process for deep-sea mining in ‘the Area’

Environmental Impact Assessment (EIA) is key to the robust environmental management of industrial projects; it is used to anticipate, assess and reduce environmental and social risks of a project. It is instrumental in project planning and execution, and often required for financing and regulatory approval to be granted. The International Seabed Authority currently requires an EIA for deep-sea mining (DSM) in areas beyond national jurisdiction (the Area), but the existing regulations present only a portion of a robust EIA process. This article presents an ideal EIA process for DSM, drawing upon the application of EIA from allied industries. It contains screening, scoping and assessment phases, along with the development of an environmental management plan. It also includes external review by experts, stakeholder consultation, and regulatory review. Lessons learned from application of EIA elsewhere are discussed in relation to DSM, including the integration of EIA into UK domestic law, and the reception of EIAs prepared for seabed ore extraction in the Exclusive Economic Zones of New Zealand and Papua New Guinea. Finally, four main challenges of implementing the EIA process to DSM in the Area are presented: 1) EIA process for DSM needs to incorporate mechanisms to address uncertainty; 2) detailed requirements for the EIA process phases should be made clear; 3) mechanisms are needed to ensure that the EIA influences decision making; and, 4) the EIA process requires substantial input and involvement from the regulator

Phase modulators ands splitting network on Si PIC coherent fiber beam combining

Coherent beam combining (CBC) of fiber lasers provide an attractive mean of reaching high output laser power by scaling up the available energy while keeping fiber intrinsic advantages of compactness, reliability, efficiency, and beam quality. In CBC architectures, the power of a master oscillator (MO) is divided into N fibers that are amplified individually. The phase perturbations between channels can be measured using various techniques [1-3] and are corrected by individual phase modulators placed on each fiber before the amplification. In this Communication, we present a Silicon PIC integrating a 1:16 channels splitting network and thermal phase modulators array with low electrical power consumption and a bandwidth compatible with CBC requirements. In our CBC system, a 1.55µm CW master oscillator directly feeds the Silicon chip through a grating coupler, as shown in Fig.1(a). The power of the master oscillator is first split on chip into 16 channels, each of which including a thermal phase modulator. The outputs of the 16 waveguides are collectively out-coupled from the chip using a PM optical fiber array aligned and glued onto the PIC’s output grating couplers array [4]. At the other end of fiber array, the 16 fiber outputs are arranged in a 4 by 4 squared lattice, and collimated by a microlens array to form 16 collimated and parallel beamlets. The phase distribution from channel to channel is derived from the fringe pattern resulting from the collimated beamlets interfering with a reference plane wave on a camera. This signal is fed back to drive the PIC’s phase modulators in order to phase lock the 16 fiber