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Microplastics are widely distributed in the environment, raising significant concerns owing to their potential negative effects on humans. Zebrafish were used in this study to assess the toxicity of microplastic exposure. Adult zebrafish were exposed to polyethylene (PE) microplastics with smooth clustered sphere shapes and diameters of 75-100 µm for 35 days. Survival rates of the zebrafish were not significantly affected, whereas growth rates were. Analyses on oxidative stress-related enzyme activities showed that glutathione (GSH), glutathione peroxidase (GSH-PX), and glutathione s-transferase (GST) production in the intestines was stimulated when exposed to low concentrations of microplastics (0.1 and 1 mg/L), while superoxide dismutase (SOD), catalase (CAT), GSH, and GSH-PX production was suppressed when exposed to 10 mg/L microplastics. Enzyme activities in the muscles were much less affected. Intestinal injuries and changes in colony structure in the intestines were observed in zebrafish following exposure to microplastics. After 35 days of exposure, concurrent exposure to microplastics and Aeromonas hydrophila did not increase zebrafish mortality compared with those challenged by bacteria alone. This study confirms that intestinal enzyme activities of zebrafish are altered by exposure to PE microplastics but mortality and bacterial infection were not significantly affected under the tested conditions.

Reclaimed water recharging rivers is an important way to solve the problem of water shortage. However, reclaimed water contains some toxic contaminants, which will cause ecological and health risks. The objective of this study is to explore the relationship between developmental toxicities and relevant water quality parameters. Zebrafish embryos were exposed to secondary effluent, wastewater with advanced treatment (Tertiary treatment effluent) and blank (Aerated tap water). The samples taken in April showed higher biological toxicity to embryos, as the maximum value of mortality and malformation reached to 47.5 % for secondary effluent, 75 % for wastewater with advance treatment, while the blank was just 2 % at 120 hours post fertilization. The tested samples also showed significantly adverse effect on hatchability of zebrafish. The hatching rates of embryos exposed to secondary effluent and tertiary treatment effluent were much lower than blank. And significant delay in hatching time existed during the hatching period. The advanced treatment did not show beneficial effects for reducing acute toxicity. The main factor resulted in hatching inhibition may be ammonia especially the free ammonia, as it showed highest coefficient with hatching rate. The no observed effect concentration (NOEC) of ammonia for mortality and malformation were 5 mg/L and 10 mg/L respectively. The lowest observed effect concentration (LOEC) of ammonia for body length and hatchability were both 2 mg/L, while the concentration of free ammonia was 0.19 mg/L. Considering the biological toxicity of ammonia on aquatic organism, the discharge concentration of ammonia is advised to be controlled below 2 mg/L.

Photocatalytic hydrogen evolution from water splitting presents an attractive prospect in dealing with the energy crisis, but the low efficiency of charge separation and migration still seriously hinders its further practical application. Here, an acidified boron-doped g-C

Microplastics that are widely distributed in the environment has raised great concerns due to their potential negative effects to humans. Zebrafish was used as the model organism in this study to assess the toxicity of microplastic exposure. The adult zebrafish were exposed to the PE microplastics in smooth clustered sphere shapes with diameters of 75-100 µm for 35 days, and the survival rate of the zebrafish were not significantly affected, whereas the growth rate was. Further analyses on the oxidative stress related enzyme activities showed that the production of GSH, GSH-PX, and GST in the intestine were stimulated when exposing to the microplastics of lower concentrations (0.1 and 1 mg/L), while the production of SOD, CAT, GSH, GSH-PX were suppressed when exposing to those of 10 mg/L. The activities of enzymes in the muscle were much less affected. The intestinal injury and changes of colony structure in the intestine were observed by exposure to the tested concentrations of microplastics. By exposure to the microplasctics for 35 days, a further concurrent exposure to microplasctics and Aeromonas hydrophila did not exacerbate the mortality of zebrafish due to bacterial infection; on the contrary, the mortality was reduced. This study confirmed the intestinal enzyme activity changes of zebrafish, but showed no sign of inducing higher mortality or exacerbating bacterial infection by chronic exposure to the microplastics.

Background Most particulate organic matter (POM) cannot be directly degraded in the conventional wastewater treatment, which should be transformed into dissolved organic matter (DOM) through a hydrolysis process. However, non-hydrolyzed POM in the biological treatment can limit treated efficiencies for the wastewater treatment plants (WWTPs) facilities. Hence an operational tool is indispensable for insight into removals of DOM and POM factions in the WWTP. In this study, excitation-emission matrix fluorescence spectroscopy (EEM) combined parallel factor analysis (PARAFAC), two-dimensional correlation (2D-COS) and structural equation modeling (SEM) was employed to evaluate removals of DOM and POM in a wastewater treatment plant. Results Four fluorescence components were identified in DOM and POM substances from the WWTP by EEM combined with PARAFAC, i.e., tyrosine-like (TYLF), tryptophan-like (TRLF), microbial byproduct-like (MBLF), and fulvic acid-like (FALF). In A2/O process, the TYLF and TRLF of DOM were removed to a larger extent than those of MBLF and FALF in anaerobic tank, while TYLF and MBLF of POM were removed to a great extent than those of TRLF and FALF in primary sedimentation and aerobic tanks. By the 2D-COS, a decreasing variation order of DOM fractions in the wastewater treatment process was UV-FALF → MBLF2 → Vis-FALF → TRLF → TYLF, while the decreasing order of POM fractions was Vis-FALF → UV-FALF → MBLF2 → TYLF → MBLF1 → TRLF. SEM revealed that TRLF and TYLF of DOM were degraded by anaerobic microorganism, and TRLF could be transformed partially into FALF. However, TRFL and TYLF of POM were discomposed by aerobic microorganism. Conclusions The 2D-COS and SEM can be practicable tools as EEM-PARAFAC for monitoring DOM and POM in the WWTP. The study could present a theoretical support to improving the retrofit of WWTP and formulating emission standards for organic pollutants.

Goals: Hepatocellular carcinoma (HCC) has been reported to be the third most common malignant tumor and has the highest rate of mortality. To increase the chemotherapy efficacy of HCC, a drug delivery system featured with desirable active targeting ability, delivery efficiency and immune evasion is in high demand. Methods: We have developed a drug nanocarrier by utilizing a homotypic cancer cell membrane for targeted chemotherapy of HCC. Structurally, the homotypic HepG2 cell membrane was used as the cloak, and a poly (lactic-co-glycolic acid) (PLGA) nanoparticle as the core, resulting in the nanocarrier HepM-PLGA. Results: The HepM-PLGA nanoparticles exhibit excellent targeting ability toward HepG2 cells. Doxorubicin (Dox) carried by HepM-PLGA possesses high delivery efficiency and a remarkable in vitro therapeutic effect. In in vivo experiments, HepM-PLGA delivers Dox directly to the tumor lesion of nude mice, and tumor volume decreases by approximately 90% after treatment. Conclusion: We have developed a drug nanocarrier by utilizing a homotypic cancer cell membrane for targeted chemotherapy of HCC with excellent active targeting ability. This biomimetic platform not only effectively treats HCC but also provides a sound strategy for the treatment of other cancers via changes in the corresponding homotypic cancer cell membrane.

The present study investigated the effect of high organic loading rates at low hydraulic retention times without pH control on food wastes fermentation. The acidogenic fermentation was robust to the hydraulic retention time drawdown. Hydraulic retention time variation led to compositional changes of fermentation product. Lactic acid and ethanol were always the dominant end-products and achieved the highest proportion (90.9%) at the 1-day hydraulic retention time. CO

BackgroundTumor recurrence in patients after surgery severely reduces the survival rate of surgical patients. Targeting and killing recurrent tumor cells and tissues is extremely important for the cancer treatment.ResultsHerein, we designed a nano-biomimetic photothermal-controlled drug-loading platformHepM-TSLwith good targeting ability and immunocompatibility for the treatment of recurrent hepatocellular carcinoma.HepM-TSLcan accurately target the recurrent tumor area with the aid of the cloaked homotypic cell membrane and release the chemotherapy drugs in a controlled manner. In vivo results have confirmed thatHepM-TSLloaded with drugs and photosensitizer achieves the synergistic treatment of recurrent hepatocellular carcinoma with good therapeutic effect and slight side effects.ConclusionAccordingly,HepM-TSLprovides a sound photothermal-chemotherapy synergistic strategy for the treatment of other recurrent cancers besides of recurrent hepatocellular carcinoma.

Introducing co-catalyst and constructing heterostructure are two of the most promising strategies in improving the photocatalytic H2 evolution performance of semiconductors. However, it has always been a great challenge to develop a facile and low-cost system to facilitate the highly efficient synergistic effect between co-catalyst and heterostructure. Herein, co-catalyst NiS decorated ZnS/CdS heterostructure (CdS/ZnS-NiS) has been fabricated by using a facile one-pot hydrothermal procedure for the photocatalytic H2 evolution from water splitting. As a result, CdS, ZnS and NiS contact closely with each other at nano scale to assemble into fluffy porous nanocomposite, the optimized CdS/ZnS-NiS exhibits a high hydrogen evolution rate of 60.44 mmol·h-1g-1 without the addition of extra noble metal co-catalyst, which is about 22.3 times higher than that of pure CdS and much higher than that of 1% wt Pt decorated CdS/ZnS (52.36 mmol·h-1g-1). One-pot fabrication process allows the formation of intimate contacted interface between different components, contributing to the sufficient exposure of active reaction sites. Moreover, noble-metal-free co-catalyst NiS distributes uniformly in both surface and inner region of porous nanocomposite. The synergistic effect between the intimately contacted heterostructure and co-catalyst boosts the separation and utilization of photogenerated charge carriers, resulting in a dramatically enhanced H2 evolution ability. This work provides a facile pathway to uniformly introduce noble-metal-free co-catalyst in heterostructure and gives out a paradigm in constructing high active solar energy conversion system.

Specific bacterial communities interact with phytoplankton in laboratory algal cultures. These communities influence phytoplankton physiology and metabolism by transforming and exchanging phytoplankton-derived organic matter. Functional bacterial groups may participate in various critical nutrients fluxes within these associations, including nitrogen (N) metabolism. However, it is unclear how bacterial communities and the associated algae respond to changes of phycosphere N conditions. This response may have far-reaching implications for global nutrient cycling, algal bloom formation, and ecosystem function. Here, we identified changes in the bacterial communities associated with Phaeodactylum tricornutum when co-cultured with different forms and concentrations of N based on the Illumina HiSeq sequencing of 16S rRNA amplicons. Phylogenetic analysis identified Proteobacteria and Bacteroidetes as the dominant phyla, accounting for 99.5% of all sequences. Importantly, bacterial abundance and community structure were more affected by algal abundance than by the form or concentration of inorganic N. The relative abundance of three gammaproteobacterial genera (Marinobacter, Algiphilus and Methylophaga) markedly increased in N-deficient cultures. Thus, some bacterial groups may play a role in the regulation of N metabolism when co-cultured with P. tricornutum.

Cr(VI) reduction to Cr(III) has been demonstrated to be an effective method for Cr(VI) detoxification. Herein, we fabricated polyaniline (PANI) nanorod forests-modified Carbon fiber felt (CFF) as CFF-PANI cathode in a Flow-through electrode system (FES) with the counter CFF anode for enhancing Cr(VI) reduction. The CFF-PANI was synthetized via in-situ polymerization under different aniline concentration to investigate the effect of PANI nano-structures on Cr(VI) reduction. It was revealed that BET and electrochemical surface area of PANI nanorods significantly affected the Cr(VI) reduction, and CFF-PANI cathode with the largest BET and electrochemical surface area exhibited ∼ 45% higher Cr(VI) removal and ∼ 35% lower specific energy consumption than the CFF cathode. A decrease-then-stable Cr(VI) removal was observed within 120 min operation time, which was attributed to the electro-adsorption of Cr(VI) species on CFF anode. In-situ sampling experiments revealed that the electrochemical oxidation on CFF anode inhibited the Cr(VI) electro-adsorption, and at applied voltage above 0.7 V, the Cr(VI) reduction on cathode was the main mechanism for Cr(VI) removal. The operation of FES at 0.8 V had the lowest specific energy consumption (48.5 Wh/mol) and maintained ∼ 95% energy efficiency for Cr(VI) reduction with minor competitive reduction of H2O or O2 species. The results suggested that CFF-PANI can be a promising cathode for Cr(VI) reduction from aqueous solutions.

Additional file 1: Figure S1. TEM image of HepG2 cell membrane(a) and the ruptured liposome after the laser irradiated (b). DLS of the TSL (c), HepM-TSL (d), HepG2 cell membrane vesicles (e). Figure S2. (A) to (E) Targeting ability of HepM-TSL to HepG2 cells, BGC-823 cells, HeLa cells, and MCF-7 cell verified by flow cytometry. (F) Quantitative fluorescence intensities of results in (A) to (E). (G) Fluorescence images of HepG2 cells, BGC-823 cells, HeLa cells, and MCF-7 cell obtained with flow cytometry. Figure S3. The targeting ability of HepM-TSL to HepG2 cells and other cancer cells. (A) Fluorescence images of HepG2 cells, BGC-823 cells, HeLa cells and MCF-7 cells incubated with ICG-Dox-HepM-TSL nanoparticles. (B) Quantitative histograms of the Dox fluorescence intensities in (A). (C) Quantitative histograms of the ICG fluorescence intensities in (A). Scale bar: 75 μm. Figure S4. Dox and ICG loading content standard curve Dox concentration of 41.32 μg/mL. ICG concentration of 34.83 μg/mg. Figure S5. Schematic diagram of in vivo experiments. Figure S6. Hemolysis effect of the ICG-Dox-HepM-TSL, ICG-Dox-TSL, ICG, Dox and Tween 80.

In recent years, more and more people express their feelings through both images and texts, boosting the growth of multimodal data. Multimodal data contains richer semantics and is more conducive to judging the real emotions of people. To fully learn the features of every single modality and integrate modal information, this paper proposes a fine-grained multimodal sentiment analysis method FCLAG based on gating and attention mechanism. First, the method is carried out from the character level and the word level in the text aspect. CNN is used to extract more fine-grained emotional information from characters, and the attention mechanism is used to improve the expressiveness of the keywords. In terms of images, a gating mechanism is added to control the flow of image information between networks. The images and text vectors represent the original data collectively. Then the bidirectional LSTM is used to complete further learning, which enhances the information interaction capability between the modalities. Finally, put the multimodal feature expression into the classifier. This method is verified on a self-built image and text dataset. The experimental results show that compared with other sentiment classification models, this method has greater improvement in accuracy and F1 score and it can effectively improve the performance of multimodal sentiment analysis.

The extensive use of antibiotics has resulted in the development of antibiotic-resistant bacteria (ARB), which may not be completely removed by traditional wastewater treatment processes. More effective approaches to disinfection are needed to prevent the release of ARB into the surface water. The metal-free photocatalyst graphitic carbon nitride (g-C

Predicting the sublethal effects of pollutants to aquatic organism is essential in realistic chemical risk assessment. However, only a few dynamics models for sublethal endpoints are available. Here, we investigated the toxic effects of the essential metal Cu and the nonessential metal Cd on Chlamydomonas reinhardtiiunder both single and combined exposure, compared the effectiveness of different effect endpoints as toxic effect factors, and developed a Dynamic Energy Budget toxicology (DEBtox) model to predict the sublethal effects of Cu and Cd on C. reinhardtii. The results showed that the chlorophyll fluorescence parameter is a better toxic effect indicator than others for short-term exposure (24 h), while algal cell growth is preferred for long-term exposure (2-6 days). The developed DEBtox model could successfully predict single metal toxicity to C. reinhardtii, while the combined metal DEBtox model slightly overestimates the joint toxicity of Cu-Cd due to the antagonistic effect of Cu-Cd on C. reinhardtii. This study is helpful to understanding and better predictions of metal sublethal toxic effects on aquatic organisms.

Using biological decomposition of plants in an agroecology system is a good method to reduce biogas slurry pollutions. The effects of biogas slurry irrigation on the growth, photosynthesis, and nutrient status of Perilla frutescens seedlings were investigated. The results indicated that biogas slurry irrigation caused a marked increase in plant height, root length, biomass of shoot and root, photosynthetic pigment content, net photosynthetic rate, transpiration rate, stomatal conductance, intercellular carbon dioxide (CO2) concentration, and water-use efficiency. Biogas slurry irrigation changed the concentration of nutrient elements of various organs.

The origin of the new A (H1N1) influenza virus recently emerging in North America is a hot controversial topic of significance in disease control and risk assessment. Some experts claimed that it was an unusually mongrelized mix of human, avian and swine influenza viruses, while some others concluded that it was totally a simple re-assortment hybrid of two lineages of swine influenza viruses. Here the phylogenetic diversity of the viral PB1, PA and PB2 gene sequences using online web servers, and the results suggest that all the 8 genetic segments of the new virus were possibly from two lineages of swine influenza viruses, and one of the lineage was a mongrelized mix of human, avian and swine influenza viruses emerging in the world approximately 10 years ago. Considering the recent epidemiological trends of the new virus, we believe it will spread more widely in the world and persist long in human populations. It also could spread among swine populations. The future wide spreading of the new virus may coincide the disappearance of a subtype of previous human influenza A virus.

The indirect ELISA is a simple and useful method for detection of pathogen-specific antibodies in animal sera. However, non-specific or background binding is often a problem, especially when recombinant proteins from Escherichia coli are used. In this study, a comparative indirect ELISA in which the total reactivity and the background binding were determined simultaneously on the same ELISA plate was reported. The background was determined by incubation of the test sera with excess free antigen to block specific binding. The sample was considered positive only when its total reactivity reading was higher than a pre-determined cut-off value and the ratio of the total reactivity to the background reading was more than 2.0. Using this approach, an antibody assay for henipaviruses using a recombinant Nipah virus nucleocapsid protein expressed in E. coli was developed. A total of 919 negative serum samples were tested in this assay and the specificity was 95.8%. In addition, eight positive experimental serum samples all tested positive. The use of recombinant protein as the ELISA antigen, instead of inactivated virus antigens, will be of significant advantage for countries where there is no facility of Biosafety level 4 to handle this group of zoonotic viruses.

Recent West Nile virus epidemics in USA draw worldwide concerns. Here the basic biological and epidemiological features of the virus are analyzed along with the special immunity of humans and animals, the immigration of birds and the natural environments in China. The risk of severe hazards to China caused by West Nile virus is assessed not high thereafter.

Local Scour is one of the key challenges for construction of bridge in deep water, especially, for bridge at the estuary of Yangtze River. The flow condition here is really complex due to rugged topography and evident tide influence. Local scour might deteriorate for the disturbance during construction of pile group and bearing platform. Thus, stability of riverbed becomes the most fundamental for the safety of pier foundation, including construction of temporary construction platform and installation of pile group. So, protection of riverbed soil is usually started before foundation of bridge. To study the real result, multi-beam echo sounder using ultrasonic is often adopted to periodically measure and mapping riverbed topography. But due to the effect of foundation, blind area often exists around the pier. At Sutong Bridge, vibrating wire piezometers using to continually monitoring local scour happened within and around pile group. Multi-beam Echo Sounder is using for the large-scale detection progress during and after construction, and the vibrating wire piezometers is using for the small-scale detection within and around the pier foundation soil. Special protection applied for the vibrating wire piezometers and its cable to avoid harm from torrent. The result shows: 1) Different scale detection systems, using vibrating wire piezometers and multi-beam echo sounder separately, can get enough and better information for the monitoring of local scour occur around pier. As an example, monitoring of riverbed protection at Sutong Bridge lead out the conclusion that protection does effect on riverbed and weaken the scour around pile group. 2) Special protection for the Vibrating Wire Piezometers and its cable is really needed.

The ability of constructed wetlands with different plants in nitrate removal were investigated. The factors promoting the rates of denitrification including organic carbon, nitrate load, plants in wetlands, pH and water temperature in field were systematically investigated. The results showed that the additional carbon source (glucose) can remarkably improve the nitrate removal ability of the constructed wetland. It demonstrated that the nitrate removal rate can increase from 20% to more than 50% in summer and from 10% to 30% in winter, when the nitrate concentration was 30-40 mg/L, the retention time was 24 h and 25 mg/L dissolved organic carbon (DOC) was ploughed into the constructed wetland. However, the nitrite in the constructed wetland accumulated a little with the supply of the additional carbon source in summer and winter, and it increased from 0.15 to 2 mg/L in the effluent. It was also found that the abilities of plant in adjusting pH and temperature can result in an increase of denitrification in wetlands. The seasonal change may also impact the denitrification.

The combined solid phase extraction (SPE)-ion chromatography (IC) method was developed for the analysis of trace haloacetic acids (HAAs) in drinking water. The tested HAAs included monochloroacetic acid (MCAA), dichloroacetic acid (DCAA), trichloroacetic acid (TCAA), monobromoacetic acid (MBAA) and dibromoacetic acid (DBAA). For trace determination of HAAs in real drinking water samples, conditions of LiChrolut EN SPE cartridge were investigated for HAAs preconcentration and matrix elimination. Elution was carried out by 2 mL of sodium hydroxide (10 mmol/L) with the flow rate of 2 mL/min. The Dionex IonPac AS16 column (250 mm x 4 mm i. d.), a high capacity and hydroxide-selective anion-exchange column designed for the determination of polarizable anions, was chosen for chromatographic separation. HAAs were analyzed with a concentration gradient of NaOH with the flow rate of 0.8 mL/min and detected by suppressed conductivity. A 500 microL sample loop was used. The detection limits of this SPE-IC method for MCAA, DCAA, DBAA and TCAA were 0.38-1.69 microg/L and MBAA was 12.5 microg/L under 25-fold preconcentration. The results demonstrate that the method is suitable for the analysis of trace haloacetic acids in drinking water.