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Aphanizomenon flos-aquae secretes paralytic shellfish poisons (PSPs), termed aphantoxins, and endangers environmental and human health via eutrophication of water worldwide. Although the molecular mechanism of neuronal PSP toxicity has been well studied, several issues remain unresolved, notably the in vivo hepatic antioxidative responses to this neurotoxin. Aphantoxins extracted from a natural isolate of A. flos-aquae DC-1 were resolved by high performance liquid chromatography. The primary components were gonyautoxins 1 and 5 and neosaxitoxin. Zebrafish ( Danio rerio ) were treated intraperitoneally with either 5.3 or 7.61 (low and high doses, respectively) μg saxitoxin (STX) equivalents (eq)/kg of A. flos-aquae DC-1 aphantoxins. Antioxidative responses in zebrafish liver were examined at different timepoints 1–24 h post-exposure. Aphantoxin administration significantly enhanced hepatic malondialdehyde (MDA) content 1–12 h post-exposure, indicative of oxidative stress and lipid peroxidation. By contrast, levels of reduced glutathione (GSH) in zebrafish liver declined significantly after 3–24 h exposure, suggesting that GSH participates in MDA metabolism. A significant upregulation of the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) was observed, suggesting that aphantoxins induce lipid peroxidation in zebrafish liver and are likely to be hepatotoxic. Hepatic levels of MDA and GSH, and of the three enzymes (SOD, CAT, and GPx), therefore provide potential biomarkers for studying environmental exposure to aphantoxins/PSPs from cyanobacterial blooms. [ABSTRACT FROM AUTHOR]

Highlights: [•] Litchi stink bug is the most significant pest in litchi and longan orchards. [•] Anastatus japonicas is an efficient enemy of Tessaratoma papillosa. [•] A. japonicus has been mass reared and successful used as a biocontrol agent. [•] Many factors constraint the utilization of A. japonicas. [ABSTRACT FROM AUTHOR]

The development of vehicular ad hoc networks (VANETs) is facing great challenges. Due to the open environment in VANETs, the false information sent by malicious vehicles not only affects the fairness of information interaction but also seriously threatens the driving safety of normal vehicles. Therefore, the study of trust evaluation and management in VANETs has become hot topics in recent years. In this paper, we propose a trust management model of VANETs based on blockchain. In this model, a hidden markov model (HMM) based vehicle trust evaluation method that improve the accuracy on the detection of malicious behavior is proposed. Besides, a trust management method based on the alliance chain is designed, which greatly improves the efficiency of trust updating and querying on the premise of security. Simulation results show that the model is promising and feasible, effective in the aspects of trust evaluation and trust management. [Display omitted] • We analyze the issues associated to the problem stated, and put forward the system model, attack model, and assumptions of the VANETs. • We propose a vehicle trust evaluation algorithm based on the HMM model with higher accuracy and better application value in the current environment of extreme computing performance. • We propose a trust management method based on hyperledger fabric, which improves the overall efficiency of the trust management and ensures better security. [ABSTRACT FROM AUTHOR]

Cold storage of host eggs is important for Trichogramma mass rearing, but the fitness of Trichogramma is affected by the refrigerated eggs. Corcyra cephalonica eggs are frequently utilized as factitious hosts of Trichogramma chilonis . In this study, we investigated the physicochemical property of fresh rice moth eggs (U) and sterilized eggs cold-stored at 4 °C for 0 (CK), 15 (N15), 30 (N30), 45 (N45), and 60 (N60) days and evaluated the effect of cold storage of host eggs on the fitness of T. chilonis . The results showed that the moisture content, dry matter and pH of C. cephalonica eggs decreased significantly with increasing cold storage time. The survival rates of T. chilonis embryos, larvae and pupae decreased significantly when C. cephalonica eggs were cold-stored for more than 15 days. The fecundity rate of adult T. chilonis in refrigerated eggs declined markedly, and a similar result was observed in the rate of black parasitized eggs. However, no clear difference was observed in either emergence rate or sex ratio between the CK and N15 treatment. A fitted linear regression model revealed that the survival rates of immature T. chilonis were positively correlated to the moisture content and pH of host eggs. Thus, cold storage changed the internal environment of C. cephalonica eggs and reduced the fitness for T. chilonis . This finding suggests that the storage period of rice moth eggs sterilized by UV at 4 °C should not exceed 15 days for mass-rearing of T. chilonis . [ABSTRACT FROM AUTHOR]

Rice moth Corcyra cephalonica eggs, frequently utilized as factitious hosts of Trichogramma wasps, are usually cold-stored for a period of time in order to meet the need of Trichogramma mass rearing. However, compounds in cold stored C. cephalonica eggs can influence the quality and quantity of Trichogramma . In the present study, we used Hydrogen-1 Nuclear Magnetic Resonance ( 1 H NMR) spectroscopy and multivariate statistical analysis to investigate the effect of cold storage on the chemical composition of fresh rice moth eggs (U) and killed embryo eggs cold stored at 4 °C for 0 (CK), 15 (N15), 30 (N30), 45 (N45), and 60 (N60) days, respectively. A total of 56 compounds were identified and quantified for each treatment, including amino acids, nucleic acid components, organic acids, sugars, and amides. Principle component analysis (PCA) and partial least square discriminant analysis (PLSDA) demonstrated that cold storage had a pronounced effect on the chemical composition of rice moth eggs. Three groups, U and CK, N15 and N30, and N45 and N60, were classified by their components’ similarity. The primary components that contributed to difference among three groups were alanine, glutamine, glucose and acetate, the concentrations of which significantly changed with the increasing of cold storage days. Thus, cold storage elicits changes in the chemical compositions of rice moth Corcyra cephalonica eggs, which may affect the growth and development of Trichogramma . [ABSTRACT FROM AUTHOR]