There is a lack of suitable tropical marine species for ecotoxicity tests. An attractive model organism for ecotoxicology is the marine amphipod Parhyale hawaiensis, which is already a model for genetic and developmental studies. This species is widespread, can tolerate changes in salinity, is easy to handle and is representative of circumtropical regions. The aim of this work was to describe standardized procedures for laboratory husbandry, define conditions for acute toxicity tests, and to provide acute toxicity test results for some reference toxicants. Culturing conditions for the organism in the laboratory were established in reconstituted seawater (30 ± 2 salinity), 24 ± 2 °C, photoperiod 12/12 h light/dark. Acute toxicity test procedures were developed for 96 h-exposure time, and organisms at ages <7 days. The miniaturized version of the test, based on 96-well microplates and 200 µL of exposure media provided consistent results compared to larger exposure volumes (80-mL vials protocol). Acute toxicity of Ag, Cd, Cu, Zn and ammonia determined for P. hawaiensis were consistent to previous results for other marine amphipods. We conclude that P. hawaiensis can be successfully cultured in standardized conditions and be effectively used in acute toxicity testing. Further development and use of this model will enable standardized and reproducible ecotoxicology investigations in understudied and vulnerable tropical marine ecosystems.

Although tons of disperse dyes are used worldwile, little information on their ecotoxicity is available. While in silico models can be used to predict their ecotoxicity, experimental results from Daphnia can show significantly higher toxicity than predicted. Thus the objective of this work was to extend the knowledge base in this area by evaluating the ecotoxicity of three widely used disperse dyes and comparing the results to predicted values. Bearing in mind that generating ecotoxicity data on azo disperse dyes is complicated because they are not readily found as homogeneous compounds, we employed chromatographic methods to purify three commercially dyes C.I. Disperse Violet 93, Blue 291, and Blue 373 already found in the aquatic environment. No acute toxicity was observed for Daphnia similis. These results seems to be in general agreement when compared with ECOSAR predicted values. We hypothesize that differences in Kow values could explain the variations in results.

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BACKGROUND This work aims to assess the use of protic ionic liquids (PIL), propanoate, butanoate and pentanoate of N‐methylmonoetanolamine (C3, C4 and C5), in the preparation of hybrid supports made of poly(3‐hydroxybutyrate‐co‐hydroxyvalerate) (PHBV) and silica for the immobilization of lipase of Burkholderia cepacia (BCL) by covalent binding. For immobilized biocatalysts (IBs), the performance was determined for immobilization and characterization (pH, temperature, stability thermal, operational and in solvents), with the best conditions being defined. For the supports and efficient IB, the morphological and physicochemical characterization (MEV, BET, FTIR and TGA) was evaluated. RESULTS For preparation of the hybrid support, the experiment using 3 g of PHBV presented a higher percentage of mass, around 50% recovery of the support in the granulometry used. The IBs total activity recovery yield (Ya) in hybrid supports modified with ionic liquids IB‐hybrid‐C3 (103%), IB‐hybrid‐C4 (120%) and IB‐hybrid‐C5 (133%) were above the results reported for the control (90%), with IB‐hybrid‐C5 being the most efficient, and presenting better thermal and operational stability. CONCLUSION Burkholderia cepacia lipase was immobilized successfully in a hybrid support (PHBV and silica) modified with protic ionic liquid by covalent binding, resulting in an improvement in the morphological and physicochemical characteristics, and consequently with greater Ya and good thermal and operational stability. © 2016 Society of Chemical Industry

In this work, a porous and homogeneous titanium dioxide layer was grown on commercially pure titanium substrate using a micro-arc oxidation (MAO) process and Ca-P-based electrolyte. The structure and morphology of the TiO2 coatings were characterized by X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy, and profilometry. The chemical properties were studied using electron dispersive X-ray spectroscopy (SEM-EDS) and X-ray photoelectron spectroscopy. The wettability of the coating was evaluated using contact angle measurements. During the MAO process, Ca and P ions were incorporated into the oxide layer. The TiO2 coating was composed of a mixture of crystalline and amorphous structures. The crystalline part of the sample consisted of a major anatase phase and a minor rutile phase. A cross-sectional image of the coating-substrate interface reveals the presence of voids elongated along the interface. An osteoblast culture was performed to verify the cytocompatibility of the anodized surface. The results of the cytotoxicity tests show satisfactory cell viability of the titanium dioxide films produced in this study.

-The average deviations related to the mole fraction between the experimental and calculated values by the NRTL were less than 2.4%.

We empirically characterize how China is internationalizing the Renminbi by selectively opening up its domestic bond market to foreign investors and propose a dynamic reputation model to explain this internationalization strategy. The Chinese government deliberately controlled the entry of foreign investors into its market, first allowing in relatively stable long-term investors like central banks before allowing in flightier investors like mutual funds. Our framework explains these patterns as the result of a government strategy to build its reputation as an international currency issuer while attempting to reduce the cost of potential capital flight as it tries to gain credibility. The dynamics of reputation make Chinese debt a substitute for emerging market risky debt in the early stages of internationalization and more of a substitute for developed market safe debt in the later stages. We use our framework to explore how countries compete to become a reserve currency provider. Competition worsens the incentives to build up reputation by reducing the benefits of having a higher reputation. The framework is tractable and can make sense of both new entrants like China and established players like the United States.

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