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Discarded plastic bag is a main component of marine debris, posing potential threats to marine biota. This study was conducted to assess the potential effects of microplastics on juvenile Lates calcarifer. Fish were exposed via diet to two microplastic types from conventional polyethylene (PE) and biodegradable (Bio) plastic bags for 21 days. Antioxidative enzymes activity, intestinal microbiome and proteome were determined. PE and Bio microplastics were found to accumulate in gastrointestinal tracts, and no mortality was observed. Microplastics exposure did not induce significant antioxidant response except for the glutathione reductase (GR) modulation. Intestinal microbiome diversity decreased significantly in PE group based on Simpson index. Both types of microplastics induced proteome modulation by down-regulating proteins associated with immune homeostasis. Bio microplastics maintained higher intestinal microbial diversity and induced more proteins alteration than PE microplastics. This study provides toxicological insights into the impacts of conventional and biodegradable microplastics on juvenile L. calcarifer. [Display omitted] • Both polyethylene and biodegradable microplastics could be consumed by juvenile Lates calcarifer. • Short-term microplastics exposure did not cause significant antioxidant response except for glutathione reductase modulation. • Polyethylene microplastics caused intestinal microbiome diversity reduction. • Both types of microplastics caused liver proteome alteration. • Few significant differences were observed between different microplastics. [ABSTRACT FROM AUTHOR]

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Abstract: The mechanisms underlying the neurotoxicity of endemic fluorosis still remain unknown. To investigate the expression level of neural cell adhesion molecules (NCAM), oxidative stress, and apoptosis induced by fluoride, the primary rat hippocampal neurons were incubated with 20, 40, and 80mg/l sodium fluoride for 24h in vitro. The results showed that the cell survival rate in the 80mg/l fluoride-treated group was significantly lower than that of the control group. Forty and 80mg/l of fluoride induced significantly increased lactate dehydrogenase release, intracellular reactive oxygen species, and the percentage of apoptosis. Compared with control group, the malondialdehyde levels were significantly elevated while glutathione levels and glutathione peroxidase activities were decreased in all fluoride-treated groups, accompanied by the markedly reduced superoxide dismutase activity in 80mg/l fluoride-treated group. With respect to NCAM mRNA expression levels, a significant dose-dependent decrease was observed in 40 and 80mg/l fluoride-treated groups against the control group. In addition, as compared to the control group, the protein expression levels of NCAM-180 in 40 and 80mg/l fluoride-treated groups, NCAM-140 in all fluoride-treated groups, and NCAM-120 in the 80mg/l fluoride-treated group were significantly decreased. Our study herein suggested that fluoride could cause oxidative stress, apoptosis, and decreased mRNA and protein expression levels of NCAM in rat hippocampal neurons, contributing to the neurotoxicity induced by fluoride. [Copyright &y& Elsevier]

This study aims to explore the morphology of void and compressive performances of CNTs-reinforced filament-wound risers under axial compressive loading. The porosity morphology and distribution induced by the filament winding process were measured and analyzed, revealing a transition from nearly circular to elongated voids with gradual growth in the size of the individual void as the winding angle increased. Failure modes of composite risers were comprehensively discussed to understand the progressive failure process and load-bearing capacity. The results indicated that failure mechanisms of composite risers mainly manifest as initial resin splitting at the end of the structure, cracks growing in the interwoven region and local buckling at the end of the structure, and local asymmetric buckling as winding angle increased. While the addition of CNTs enhances the brittleness of the substrate and leads to an increased probability of debonding and delamination. Furthermore, the experiment results demonstrate that the energy absorption capacity can be generally improved at larger winding angles for the composite riser with 3% and 5% of CNTs volume content. The maximum values of peak crushing load, mean crushing force, energy absorption, and specific energy absorption were observed in the circumferentially wound riser with 5% of CNTs volume content. • The shape of voids transitions with an increase in winding angle. • There is a slight sensitivity of the void content to the winding angle. • Failure mode is similar to the different composite risers with the same winding angle. • Large winding angles improve energy absorption for 1% and 5% of CNTs volume content. • Winding angle strongly affects the compressive performance but no nonlinear is observed. [ABSTRACT FROM AUTHOR]

• High connection between pelagic and benthic origin both in Wanshan Island and Wailingding Island with shallow waters. • Both fishes and macroinvertebrates are largely fueled by pelagic production in Wanshan Island. • Key environmental factors influencing the isotopic niches of fishes and macroinvertebrates were identified. Artificial reefs are frequently deployed in marine ecosystems to increase fishery yields and enhance the production of reef-associated fauna. However, information regarding trophic structures and pathways of faunal assemblages in artificial reef ecosystems in Pearl River Estuary were still in scare. To this end, we compared the abundances and isotopes of functional groups of fishes and macroinvertebrates in three offshore islands, including Wanshan Island with shallow artificial reefs, Miaowan Island with deep artificial reefs, and Wailingding Island with no reef. The results showed that high connection between pelagic and benthic origin in Wanshan and Wailingding Islands, with pelagic production dominating in Wanshan Island and benthic production dominating in Wailingding Island, respectively. The δ13C value of fishes was significantly lower in Wanshan Island compared to Miaowan Island and Wailingding Island, whilst the δ 15N value of macroinvertebrates was highest in Miaowan Island. Based on the trophic niches, Wanshan Island displayed higher trophic diversity and lower trophic redundancy in fish assemblages, while Miaowan Island was the same in macroinvertebrate assemblages. In addition, four key environmental indicators (i.e., salinity, pH, phosphate, and chemical oxygen demand) and five key environmental indicators (i.e., depth, dissolved oxygen, chlorophyll a , total phosphate, and transparency) were the best at explaining the niche variation of fishes and macroinvertebrates, respectively. Our findings provide an understanding of ecosystem functioning within and around the artificial reef systems to further enhance effective management. [ABSTRACT FROM AUTHOR]

Abstract: Two brachiopod genera, Cancrinella Fredericks and Costatumulus Waterhouse, are studied from the Permian of South Mongolia and South China. Many of the specimens previously described as Cancrinella are revised and assigned to Costatumulus. The new data presented in this paper indicate that these two genera are similar to each other, but are distinguishable by different features in relation to their morphology. Several species of both genera are described here, providing critical new information on the morphology and taxonomy of Cancrinella and Costatumulus. The reported biostratigraphical information reveals that species of Cancrinella are present from the Lower Carboniferous (Tournaisian) to Middle Permian (Capitanian), whereas species of Costatumulus are mostly restricted to the Lower Permian (Sakmarian) to Upper Permian (Changhsingian). An analysis of the palaeogeographical distribution of Cancrinella and Costatumulus reveals that Cancrinella was more commonly distributed in the Northern Transitional Zone and the Boreal Realm, in contrast to Costatumulus, which tended to be more common in the Southern Transitional Zone and Gondwanan Realm. [Copyright &y& Elsevier]