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Microplastic (MPs) pollution is a global marine environmental problem. The effects of MPs on the gut microbiota of aquatic organisms have received considerable attention. For example, microbes colonizing MPs in pond cultures alter the structure and function of the intestinal microbes of shrimp and fish. It was hypothesized that bacteria on MPs in natural mariculture areas also interact with the intestinal flora of golden pompano (Trachinotus ovatus) because biofilms can form on the surface of MPs during long-term floating in seawater. To our knowledge, this study is the first to investigate MPs pollution in T. ovatus aquaculture. DNA sequencing and bioinformatics analysis confirmed the effect of microbial colonization of MPs on the intestinal flora of T. ovatus. The MPs detected in the gut wet weight (w.w.) of golden pompano (546 ± 52 items/g) were mainly pellets and fragments of blue or green, whereas the sediment MPs dry weight (d.w.) (4765 ± 116 items/kg) were mainly black fibers. The MPs richness in the sediment gradually increased from the open-sea aquaculture area to the estuarine aquaculture area and was positively correlated with the MPs richness in the intestinal tract of golden pompano. MPs 20-200 μm were the most common in the gut and sediment. The intake of MPs increased the abundance of Proteobacteria and decreased that of Firmicutes in the intestinal flora. The functional compositions of MP-colonizing microbes and gut microbiota were similar, suggesting that the two communities influence each other. Network analysis further confirmed this and revealed that Vibrio plays a key role in the intestinal flora and surface microorganisms of MPs. Overall, the intake of MPs by aquatic animals not only affects the intestinal flora and intestinal microbial function, but also poses potential risks to aquaculture.

This study aimed to investigate the intoxication mechanism of golden pompano (Trachinotus ovatus) exposed to high ammonia levels and the effects on the immune and antioxidant mechanisms of gills. Juvenile golden pompano was exposed to ammonia (total ammonia: 26.9 mg/L) to induce 96 h of ammonia stress, and a 96 h recovery experiment was performed after poisoning. Then, we evaluated hematological parameters, the histological structure and the expression of related genes. In this experiment, continuous exposure to high levels of ammonia led to a significant increase in plasma alkaline phosphatase (ALP), acid phosphatase (ACP) and lactate dehydrogenase (LDH) levels (P < 0.05), and the levels of triiodothyronine (T3) and tetraiodothyronine (T4) were significantly reduced (P < 0.05). Moreover, the expression of antioxidant genes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and inflammatory cytokines such as tumor necrosis factor α (TNF-α) and interleukin 1β (IL-1β) increased (P < 0.05). These results indicate that ammonia activates the active osmotic regulatory mechanism of fish gills and participates in defense and immune responses. However, with prolonged exposure to ammonia, the balance of the defense system is disrupted, leading to oxidative damage and inflammation of the gill tissue. This research not only helps elucidate the intoxication mechanism of golden pompano by ammonia at the molecular level but also provides a theoretical basis for further research on detoxification mechanisms.

Microplastics could be grazed by marine organisms and possibly transferred to higher trophic levels along the microbial loop. Due to their size and capacity to concentrate heavy metals that trigger joint toxic effects, microplastics (MPs) have already become a severe threat to marine organisms. The detrimental effects of MPs on large marine organisms have been studied, but the combined toxicity of MPs and cadmium (Cd) on protozoan ciliates remains unclear. In the present study, we selected different diameters and concentrations of polystyrene microspheres (PS-MPs) and Cd

Continuous exposure to high levels of ammonia can cause oxidative damage to fish tissues and organs. To date, the mechanism by which juvenile golden pompano (Trachinotus ovatus) are poisoned by ammonia exposure has not been thoroughly elucidated. although the mechanisms of ammonia toxicity are not well described for the pompano, many other studies presented these effects to other fish species. So an overview would be given. First, an acute ammonia nitrogen toxicity experiment on juvenile golden pompano obtained a 96-h half-lethal concentration (96 h LC50) of 26.9 mg/L. In the ammonia exposure experiment, fish were sampled at 0 h, 6 h, 12 h, 24 h, 48 h, 72 h and 96 h after exposure to ammonia water (26.93 mg/L). The results showed that with the prolonged ammonia nitrogen exposure, plasma cortisol (COR), total cholesterol (TC), glutamic-pyruvic transaminase (ALT), glutamic oxalacetic transaminase (AST) and malonaldehyde (MDA) levels continued to rise, while glucose (GLU) levels first increased and later gradually decreased after 12 h. The activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in the liver and the mRNA expression levels of antioxidant genes (SOD, CAT, and GPX) first increased and subsequently decreased with increasing exposure time. Through microscopic observation, it was found that the degree of liver damage increased with increasing stress time and was most serious at 96 h. In the post-poison recovery experiment, the fish exposed to ammonia were transferred to clean water, and samples were taken at 24 h, 48 h, 72 h and 96 h after recovery. The results showed that with the increasing recovery time, each index recovered to the initial level to varying degrees, but the recovery time of 96 h was not enough for the fish to return to the normal level. We also examined the regulation of the Nrf2-Keap1 signaling pathway by the molecular mechanism of the antioxidant defense system. The results of this analysis showed that there was a positive correlation between Nrf2 and liver antioxidant gene expression levels, while there was a negative correlation between Keap1 and liver antioxidant gene expression levels, which may be observed because Nrf2 plays a key role in inducing antioxidant genes, and Keap1 may hinder the response to Nrf2. These results may provide a deeper and more comprehensive understanding of the impact of ammonia exposure on fish and help to provide a foundation for managing the healthy reproduction of juvenile fish.

Cooperative vehicle safety systems (CVSSs) rely on vehicular networking for broadcasting state information in order to track neighbors’ positions and, therefore, to predict potential collisions. In vehicular networking, a large number of vehicles compete for access to the limited channel resource, causing channel congestion. The vehicle tracking accuracy, which is the basis for CVSSs, therefore, can be heavily affected. Moreover, the available channel resources must be shared among vehicles in a fair way in order to maintain accurate tracking accuracy for each vehicle. To realize fair access to channel resources while maintaining an accurate tracking performance under conditions of dynamic vehicle density, in this paper, we present a distributed fair transmission rate control strategy, based on multi-agent model predictive control (MPC). We first propose a dynamic information dissemination rate model to capture the state information dissemination ability under conditions of dynamic vehicle density. Then, we present a multi-agent information dissemination model, in which each vehicle is controlled by a control agent that uses MPC and coordinates with its neighboring agents in order to determine its optimal transmission rate actions. We then design an augmented-Lagrangian-based distributed decision-making scheme to find the optimal transmission rate actions and, at the same time, reach an agreement on fair and efficient channel utilization among the vehicles. Simulation results confirm that the distributed transmission rate control strategy can guarantee fair access to channel resources while achieving the optimal vehicle tracking performance under conditions of dynamic vehicle density.

The butyryl galactose ester-modified coix component microemulsions (But-Gal-CMEs) was developed for enhanced liver tumor-specific targeting. The study was aimed to evaluate the hepatoma-targeting potential of But-Gal-CMEs in vitro and in vivo. But-Gal-CMEs with a uniform spherical shape exhibited a small particle size (56.68 ± 0.07 nm), a narrow polydispersity (PDI, 0.144 ± 0.005) and slightly negative surface charge (−0.102 ± 0.008 mV). In the cell uptake studies, But-Gal-CMEs showed a significant enhancement on the intracellular fluorescent intensity on HepG2 cells model, which was 1.93-fold higher relative to coix component microemulsions (CMEs). The IC50 of But-Gal-CMEs against HepG2 cells was 64.250 μg/mL, which was notably stronger than that of CMEs. In the cell apoptosis studies, compared with CMEs, But-Gal-CMEs (50 μg/mL) treatment resulted in a 1.34-fold rise in total apoptosis cells of HepG2. In the biodistribution studies in vivo, the intratumorous fluorescence of Cy5-loaded But-Gal-CME...

in face of urban traffic congestion, the existing trafficcontrol system available today pursues rapid evacuation of vehicles at singleintersection and fails to take into account of the coordination between intersections,resulting in the worsening of urban traffic congestion. In order to solve theurban traffic congestion problem, an adaptive control based on the priority ofthe city path is proposed based on the PageRank priority model, a bettersolution to the traffic congestion of the city. In this strategy, the aim is tominimize the queue length of vehicles in urban road network. The releasepriority of each section is calculated based on the PageRank model. For asingle intersection point of control, the vehicle traffic volume is optimizedby the Maximum Clique Problem theory. The experiment takes 19 intersections inDalian as examples and is carried out on the VISSIM traffic simulation platform.The simulation results show that the adaptive control based on the pathpriority has good effect on reducing urban traffic congestion and evacuating vehicles.

Objective: To study and analyze the influence state of hyperthermic intraperitoneal chemotherapy for the recurrence and metastasis related indexes, tumor markers of patients with gastric cancer operation. Methods: A total of 62 patients with gastric cancer operation in our hospital during the period of February 2015 to February 2016 were divided into two groups by the method of random number table, each group included 31 cases, the control group were treated with conventional perioperative treatment, the observation group were treated with hyperthermic intraperitoneal chemotherapy on the conventional treatment. Then the serum expression levels of recurrence and metastasis related indexes, tumor markers of two groups before the treatment and at different time after the treatment were compared. Results: The serum expression levels of recurrence and metastasis related indexes, tumor markers of two groups before the treatment were compared, while the serum expression levels of recurrence and metastasis related indexes, tumor markers of observation group at different time after the treatment were all significantly lower than those of control group. Conclusion: The control role of hyperthermic intraperitoneal chemotherapy for the recurrence and metastasis related indexes, tumor markers of patients with gastric cancer operation are better, and its application value in the patients with gastric cancer operation is higher.

As a type of Mobile Ad-Hoc Network (MANET), Vehicle Ad-hoc Network (VANET) has its own features such as high speed vehicles, large number of vehicles and highly dynamic driving environment. These features bring new requirements to VANET. Transmission speed, respond time and reliability level of communication have very strict instantaneity and Quality of service (QoS) demands. There are many optimized designs to satisfy the demands on each layer of communication in VANET. But there are lack of optimized works on safety messages’ communication sub-layer. In this paper, we introduce queuing theory to model and design the communication sub-layer. The results of simulation and field test show our design has achieved the requirements on both performance and function. The average improvements on performance are one times than before.

Since the IEEE 1609/WAVE standards were published, much research has continued on validation and optimization. However, precise simulation models of these standards are lacking recently, especially within the ns-3 network simulator. In this paper, we present the ns-3 implementation details of the IEEE 1609.4 and IEEE 802.11p standards which are key elements of the WAVE MAC layer. Moreover we discuss some implementation issues and describe our solutions. Lastly, we also analyze and evaluate the performance of the WAVE MAC layer with the implemented model. Our simulation results show that multiple channel operation specified in the WAVE standards could impact vehicular wireless communication differently, depending on the different scenarios, and the results should be considered carefully during the development of VANET applications.