All-Dielectric Integrated Meta-Antenna Operating in 6G Terahertz Communication Window.

Efficient transceivers and antennas at terahertz frequencies are leading the development of 6G terahertz communication systems. The antenna design for high-resolution terahertz spatial sensing and communication remains challenging, while emergent metallic metasurface antennas can address this issue but often suffer from low efficiency and complex manufacturing. Here, an all-dielectric integrated meta-antenna operating in 6G terahertz communication window for high-efficiency beam focusing in the sub-wavelength scale is reported. With the antenna surface functionalized by metagrating arrays with asymmetric scattering patterns, the design and optimization methods are demonstrated with a physical size constraint. The highest manipulation and diffraction efficiencies achieve 84.1% and 48.1%. The commercially accessible fabrication method with low cost and easy to implement has been demonstrated for the meta-antenna by photocuring 3D printing. A filamentous focal spot is measured as 0.86λ with a long depth of focus of 25.3λ. Its application for integrated imaging and communication has been demonstrated. The proposed technical roadmap provides a general pathway for creating high-efficiency integrated meta-antennas with great potential in high-resolution 6G terahertz spatial sensing and communication applications.

Improved YOLOv7 Network Model for Gangue Selection Robot for Gangue and Foreign Matter Detection in Coal.

Coal production often involves a substantial presence of gangue and foreign matter, which not only impacts the thermal properties of coal and but also leads to damage to transportation equipment. Selection robots for gangue removal have garnered attention in research. However, existing methods suffer from limitations, including slow selection speed and low recognition accuracy. To address these issues, this study proposes an improved method for detecting gangue and foreign matter in coal, utilizing a gangue selection robot with an enhanced YOLOv7 network model. The proposed approach entails the collection of coal, gangue, and foreign matter images using an industrial camera, which are then utilized to create an image dataset. The method involves reducing the number of convolution layers of the backbone, adding a small size detection layer to the head to enhance the small target detection, introducing a contextual transformer networks (COTN) module, employing a distance intersection over union (DIoU) loss border regression loss function to calculate the overlap between predicted and real frames, and incorporating a dual path attention mechanism. These enhancements culminate in the development of a novel YOLOv71 + COTN network model. Subsequently, the YOLOv71 + COTN network model was trained and evaluated using the prepared dataset. Experimental results demonstrated the superior performance of the proposed method compared to the original YOLOv7 network model. Specifically, the method exhibits a 3.97% increase in precision, a 4.4% increase in recall, and a 4.5% increase in mAP0.5. Additionally, the method reduced GPU memory consumption during runtime, enabling fast and accurate detection of gangue and foreign matter.

Diagnostic value of combined pelvic floor ultrasound parameters for pelvic floor dysfunction and risk factors.

OBJECTIVE: To investigate the diagnostic value of pelvic floor ultrasound parameters in combination for pelvic floor dysfunction (PFD), and to explore the risk factors. METHODS: Forty PFD patients treated from April2019to December 2020(case group) and another 40 healthy women (control group) were enrolled. Their clinical data were collected, and both groups received three-dimensional (3D) ultrasound of the pelvic floor. The diagnostic value of pelvic floor ultrasound parameters for PFD was assessed by receiver operating characteristic (ROC) curves. The risk factors of PFD were evaluated by multivariate logistic regression analysis. RESULTS: The area under the ROC curve (AUC), sensitivity, and specificity of the parameters in combination for predicting PFD were 0.851 [95% confidence interval (CI): 0.743-0.959], 0.901, and 0.812, respectively, indicating acceptable accuracy. Results of logistic regression analysis revealed that spontaneous delivery, lateral episiotomy/laceration, and large bladder neck rotation angle, posterior urethrovesical angle (PUA), bladder neck tilt angle, bladder neck distance (BND), levator hiatus area (LHA) (at anal contraction), R-LHA and V-LHA were risk factors for PFD (p < 0.05), while physical exercise was a protective factor (p < 0.05). ROC curve analysis revealed that the AUC, sensitivity, and specificity of the forest map model were 0.822 (95% CI: 0.759-0.885), 0.942, and 0.601, respectively, indicating acceptable accuracy of the model. Internal data validation of the model demonstrated consistence of the predicted occurrence of PFD with the actual one. CONCLUSIONS: Spontaneous delivery, lateral episiotomy/laceration, and large bladder neck rotation angle, PUA, bladder neck tilt angle, BND, LHA (at anal contraction), R-LHA and V-LHA were risk factors for PFD.

Identification and Analysis of the Expression of the PIP5K Gene Family in Tomatoes.

To explore the function of phosphatidylinositol 4-phosphate 5-kinase (PIP5K) in tomatoes, members of the tomato PIP5K family were identified and characterized using bioinformatic methods, and their expression patterns were also analyzed under salt stress and in different tissues. Twenty-one PIP5K members-namely, SlPIP5K1-SlPIP5K21-were identified from ten chromosomes, and these were divided into three groups according to a phylogenetic analysis. Further bioinformatic analysis showed four pairs of collinear relationships and fragment replication events among the SlPIP5K family members. To understand the possible roles of the SlPIP5Ks, a cis-acting element analysis was conducted, which indicated that tomato PIP5Ks could be associated with plant growth, hormones, and stress responses. We further validated the results of the in silico analysis by integrating RNA-seq and qRT-PCR techniques for salt- and hormone-treated tomato plants. Our results showed that SlPIP5K genes exhibited tissue- and treatment-specific patterns, and some of the SlPIP5Ks exhibited significantly altered expressions after our treatments, suggesting that they might be involved in these stresses. We selected one of the SlPIP5Ks that responded to our treatments, SlPIP5K2, to further understand its subcellular localization. Our results showed that SlPIP5K2 was located on the membrane. This study lays a foundation for the analysis of the biological functions of the tomato SlPIP5K genes and can also provide a theoretical basis for the selection and breeding of new tomato varieties and germplasm innovation, especially under salt stress.

Effects of ozone on activated sludge: performance of anaerobic digestion and structure of the microbial community.

The treatment and disposal of activated sludge are currently challenging tasks in the world. As a common biological engineering technology, biological fermentation exists with disadvantages such as low efficiency and complex process. Ozone pretreatments are commonly applied to improve this problem due to their high efficiency and low cost. In this study, the significant function of ozone in anaerobic fermentation gas production was verified with excess sludge. Compared with other untreated sludge, ozone pretreatment can effectively degrade activated sludge. After ozone treatment and mixing with primary sludge, the methane production of excess sludge increased by 49.30 and 50.78%, and the methanogenic activity increased by 69.99 and 73.83%, respectively. The results indicated that the mixing of primary sludge with excess sludge possessed synergistic effects, which contributed to the anaerobic fermentation of excess sludge. The results of microbial community structure exhibited that methanogenic processes mainly involve hydrogenogens, acidogens and methanogens. The relative abundance of both bacteria and microorganisms changed significantly in the early stage of hydraulic retention time, which coincided exactly with the gas production stage. This study provided a feasible pretreatment strategy to improve sludge biodegradability and revealed the role of microorganisms during anaerobic digestion.

Recent advances in the biodegradation of azo dyes.

As dye demand continues to rapidly increase in the food, pharmaceutical, cosmetic, paper, textile, and leather industries, an industrialization increase is occurring. Meanwhile, the degradation and removal of azo dyes have raised broad concern regarding the hazards posed by these dyes to the ecological environment and human health. Physicochemical treatments have been applied but are hindered by high energy and economic costs, high sludge production, and chemicals handling. Comparatively, the bioremediation technique is an eco-friendly, removal-efficient, and cost-competitive method to resolve the problem. This paper provides scientific and technical information about recent advances in the biodegradation of azo dyes. It expands the biodegradation efficiency, characteristics, and mechanisms of various microorganisms containing bacteria, fungi, microalgae, and microbial consortia, which have been reported to biodegrade azo dyes. In addition, information about physicochemical factors affecting dye biodegradation has been compiled. Furthermore, this paper also sketches the recent development and characteristics of advanced bioreactors.

Assessing the potential risk and relationship between microplastics and phthalates in surface seawater of a heavily human-impacted metropolitan bay in northern China.

The impacts of microplastics (MPs) and phthalates (PAEs), a class of MP-associated contaminants, on the marine environment are not thoroughly understood despite concern over their adverse effects on humans and ecosystems. Field studies linking MPs and PAEs in seawater have not yet been reported. We investigate for the first time the correlation between MPs contamination and the presence of PAEs in the surface seawater of Jiaozhou Bay (JZB), a semi-enclosed metropolitan bay in northern China heavily impacted by human activity. The abundance of MPs, dominated by polyethylene and polyethylene terephthalate mostly smaller than 2 mm, ranged between 24.44 items/m3 and 180.23 items/m3, with the majority being black and transparent fibers and fragments. Concentrations of PAEs varied from 129.96 ng/L to 921.22 ng/L. Relatively higher abundances of MPs and higher concentrations of PAEs were generally found in areas near riverine inputs and sewage treatment plants. There was a strong correlation between PAEs concentration and MPs abundance, suggesting that they are closely linked. In a risk assessment combining PAEs and MPs, the risk quotients (RQs) indicated that the ecological risk of di-n-butyl phthalate in JZB was relatively high (0.046

Generation of bioartificial hearts using decellularized scaffolds and mixed cells.

BACKGROUND: Patients with end-stage heart failure must receive treatment to recover cardiac function, and the current primary therapy, heart transplantation, is plagued by the limited supply of donor hearts. Bioengineered artificial hearts generated by seeding of cells on decellularized scaffolds have been suggested as an alternative source for transplantation. This study aimed to develop a tissue-engineered heart with lower immunogenicity and functional similarity to a physiological heart that can be used for heart transplantation. MATERIALS AND METHODS: We used sodium dodecyl sulfate (SDS) to decellularize cardiac tissue to obtain a decellularized scaffold. Mesenchymal stem cells (MSCs) were isolated from rat bone marrow and identified by flow cytometric labeling of their surface markers. At the same time, the multi-directional differentiation of MSCs was analyzed. The MSCs, endothelial cells, and cardiomyocytes were allowed to adhere to the decellularized scaffold during perfusion, and the function of tissue-engineered heart was analyzed by immunohistochemistry and electrocardiogram. RESULTS: MSCs, isolated from rats differentiated into cardiomyocytes, were seeded along with primary rat cardiomyocytes and endothelial cells onto decellularized rat heart scaffolds. We first confirmed the pluripotency of the MSCs, performed immunostaining against cardiac markers expressed by MSC-derived cardiomyocytes, and completed surface antigen profiling of MSC-derived endothelial cells. After cell seeding and culture, we analyzed the performance of the bioartificial heart by electrocardiography but found that the bioartificial heart exhibited abnormal electrical activity. The results indicated that the tissue-engineered heart lacked some cells necessary for the conduction of electrical current, causing deficient conduction function compared to the normal heart. CONCLUSION: Our study suggests that MSCs derived from rats may be useful in the generation of a bioartificial heart, although technical challenges remain with regard to generating a fully functional bioartificial heart.

The effect of hydrodynamic forcing on the transport and deposition of polybrominated diphenyl ethers (PBDEs) in Hangzhou Bay.

Surface sediment samples (n = 92) were collected from Hangzhou Bay to investigate the transport and deposition of polybrominated diphenyl ethers (PBDEs) and to assess the ecological risks in Hangzhou Bay. The concentrations of ∑7PBDEs (sum of BDE-28, 47, 99, 100, 153, 154, 183) and BDE-209 ranged from 3.61 to 91.09 pg g-1 and from non-detectable to 2007.52 pg g-1 (dry weight), respectively. The high values of ∑7PBDEs and BDE-209 were commonly occurred at the northeast of Hangzhou Bay and the Nanhui Spit coast of Shanghai. Compared with the south part of the bay, the dominance of BDE-209 was more prominent and the linear correlations between PBDEs concentrations and TOCs as well as median grain size were more significant in the northern Hangzhou Bay. Hydrodynamic forcing on the transport and deposition of PBDEs is primarily responsible for the discrepancy of this spatial distribution in these two parts. In addition to BDE-209, BDEs-153, 99, 47, and 100 were also the abundant congeners. Three principal components were extracted using principal component analysis (PCA), mainly attributed to human activities, erosion of polluted soils via surface runoff and release from products for PC1, PC2 and PC3, respectively. The calculation results of mass inventories, hazard quotients (HQs) and risk quotients (RQs) indicated that the ecological risk of PBDEs in Hangzhou Bay was low. The multiple effect of hydrodynamic forcing with complicated and large-scope tidal currents made it hard to deposit for organic matters and contaminants in Hangzhou Bay.

A highly reproducible cervical cuff technique for rat-to-mouse heterotopic heart xenotransplantation.

Xenotransplantation is an effective way to solve the problem of donor shortage in clinical transplantation. However, clinical use of xenotransplantation is currently limited due to immunological challenges such as acute vascular rejection and cell-mediated rejection. To finally surpass this immunological barrier, more preclinical research is needed into the molecular mechanisms of rejection and the possible effects of new immunosuppressants. Our aim was to create a refined, highly reproducible protocol to establish the most suitable rat-to-mouse heterotopic heart transplantation model using the cuff technique.

Quantitatively assessing the health risk of exposure to PAHs from intake of smoked meats.

Smoked meat and meat products represent a significant part of the daily diet in south-west China and many other parts of the world. In this study, we evaluated the health risks of long-term exposure to polycyclic aromatic hydrocarbons (PAHs) in a daily low dose exposures (from intake of PAH-containing smoked meats) in south-west China for eight groups of people based on a Monte Carlo simulation. Total concentrations of PAHs in smoked meats from south-west China ranged from 14.4 to 56.3µgkg(-1). The 95th percentile carcinogenic risk (CR) values of eight groups in four cities and provinces were lower than the acceptable value (1.00E-5), indicating no significant risk. The 95th percentile Hazard Index (HI) values were below 1, suggesting no obvious non-carcinogenic effects developed. This study was the first attempt to provide information on the potential health risk for daily intake of PAH-containing smoked meat.

Immobilization of Cyclooxygenase-2 on Silica Gel Microspheres: Optimization and Characterization.

In this study, immobilized COX-2 was successfully constructed through glutaraldehyde-mediated covalent coupling on functional silica gel microspheres. The optimum conditions, properties, and morphological characteristics of the immobilized COX-2 were investigated. The optimal immobilization process was as follows: about 0.02 g of aminated silica gel microspheres was activated by 0.25% GA solution for 6 h and mixed with 5 U of free recombinant COX-2 solution. Then, the mixture was shaken for 8 h at 20 °C. Results showed that the immobilized COX-2 produced by this method exhibited excellent biocatalytic activity, equivalent to that of free COX-2 under the test conditions employed. The best biocatalytic activity of immobilized COX-2 appeared at pH 8.0 and still maintained at about 84% (RSD < 7.39%, n = 3) at pH 10.0. For temperature tolerance, immobilized COX-2 exhibited its maximum biocatalytic activity at 40 °C and about 68% (RSD < 6.99%, n = 3) of the activity was maintained at 60 °C. The immobilized COX-2 retained over 85% (RSD < 7.26%, n = 3) of its initial biocatalytic activity after five cycles, and after 10 days storage, the catalytic activity of immobilized COX-2 still maintained at about 95% (RSD < 3.08%, n = 3). These characteristics ensured the convenient use of the immobilized COX-2 and reduced its production cost.

Bioaerosols in the coastal region of Qingdao: Community diversity, impact factors and synergistic effect.

Atmospheric bioaerosols are influenced by multiple factors, including physical, chemical, and biotic interactions, and pose a significant threat to the public health and the environment. The nonnegligible truth however is that the primary driver of the changes in bioaerosol community diversity remains unknown. In this study, putative biological association (PBA) was obtained by constructing an ecological network. The relationship between meteorological conditions, atmospheric pollutants, water-soluble inorganic ions, PBA and bioaerosol community diversity was analyzed using random forest regression (RFR)-An ensemble learning algorithm based on a decision tree that performs regression tasks by constructing multiple decision trees and integrating the predicted results, and the contribution of different rich species to PBA was predicted. The species richness, evenness and diversity varied significantly in different seasons, with the highest in summer, followed by autumn and spring, and was lowest in winter. The RFR suggested that the explanation rate of alpha diversity increased significantly from 73.74 % to 85.21 % after accounting for the response of the PBA to diversity. The PBA, temperature, air pollution, and marine source air masses were the most crucial factors driving community diversity. PBA, particularly putative positive association (PPA), had the highest significance in diversity. We found that under changing external conditions, abundant taxa tend to cooperate to resist external pressure, thereby promoting PPA. In contrast, rare taxa were more responsive to the putative negative association because of their sensitivity to environmental changes. The results of this research provided scientific advance in the understanding of the dynamic and temporal changes in bioaerosols, as well as support for the prevention and control of microbial contamination of the atmosphere.

Mixed probiotics reduce the severity of stress-induced depressive-like behaviors.

In recent years, the gut microbiome has gained significant attention in the spheres of research and public health. As a result, studies have increasingly explored the potential of probiotic dietary supplements as treatment interventions for conditions such as anxiety and depression. The present study examined the effect of mixed probiotics (Lacticaseibacillus rhamnosus and Enterococcus faecium) on inflammation, microbiome composition, and depressive-like behaviors in a macaque monkey model. The mixed probiotics effectively reduced the severity of depressive-like behaviors in macaque monkeys. Further, treatment with mixed probiotics gradually increased the abundance of beneficial bacteria in the gut, improving the balance of the gut microbiota. Additionally, macaques treated with the mixed probiotics showed decreased serum levels of inflammatory factors (P < 0.05), an increased rate of L-tryptophan metabolism (P < 0.05), and the restoration of 5-HT and 5-HTP levels (P < 0.05). Correlation analysis confirmed that Lacticaseibacillus and other beneficial bacteria exhibited a negative correlation with inflammation in the body (P < 0.05), and a positive correlation with tryptophan metabolism (P < 0.05). In conclusion, the mixed probiotics effectively restored intestinal homeostasis in macaques and enhanced tryptophan metabolism, ultimately alleviating inflammation and depressive-like behaviors.

Occurrence and prevalence of per- and polyfluoroalkyl substances in the sediment pore water of mariculture sites: Novel findings of PFASs from the Bohai and Yellow Seas using a newly established analytical method.

A new method for the determination of 26 legacy and emerging per- and polyfluoroalkyl substances (PFASs) in marine sediment pore water was developed using online solid phase extraction coupled with liquid chromatography-tandem mass spectrometry. The proposed method requires only about 1 mL of pore water samples. Satisfactory recoveries of most target PFASs (83.55-125.30 %) were achieved, with good precision (RSD of 1.09-16.53 %), linearity (R2 ≥ 0.990), and sensitivity (MDLs: 0.05 ng/L-5.00 ng/L for most PFASs). Subsequently, the method was applied to determine PFASs in the sediment pore water of five mariculture bays in the Bohai and Yellow Seas of China for the first time. Fifteen PFASs were detected with total concentrations ranging from 150.23 ng/L to 1838.48 ng/L (mean = 636.80 ng/L). The ∑PFASs and PFOA concentrations in sediment pore water were remarkably higher than those in surface seawater (tens of ng/L), indicating that the potential toxic effect of PFASs on benthic organisms may be underestimated. PFPeA was mainly distributed in pore water, and the partition of PFHpA (50.99 %) and PFOA (49.01 %) was almost equal in the solid and liquid phases. The proportions of all other PFASs partitioned in marine sediments were significantly higher than those in pore water.

CBX8 Promotes Cell Proliferation and Metastasis and Leads to Radiotherapy Tolerance of Glioma Cells.

AIM: To illustrate the role of CBX8 -a protein involved in protein metabolism and chromatin regulation/acetylation- in glioma cells, especially in DNA damage repair pathways. MATERIAL AND METHODS: Detect CBX8 expression in glioma cells and clinical samples by qPCR and Western blot. Overexpression and knockdown CBX8 cell lines were constructed by lentivirus infection. CCK8, wound healing, and transwell assays were used to verify the effects of CBX8 on proliferation, migration, and invasion of glioma cells. After radiation treatment, CCK8 and colony formation assays were used to detect cell sensitivity of CBX8 expression levels to radiotherapy. Western blot detected expression levels of p-ATM, p-ATR, BRCA-1, RAD51, and P53 in various cells after radiation treatment, demonstrating CBX8?s effect on DNA damage and repair proteins. Finally, the sensitivity of tumors with different CBX8 expression levels to radiotherapy was verified in vivo. RESULTS: CBX8 expression is significantly increased in glioma. High CBX8 expression promotes proliferation, invasion, and migration of glioma cells. It also causes glioma cells to resist radiotherapy. CBX8 affects protein expression related to DNA damage repair. In vivo, tumors with low CBX8 expression are more sensitive to radiotherapy. CONCLUSION: CBX8 promotes proliferation and metastasis of glioma cells and reduces cell sensitivity to radiotherapy by affecting DNA damage repair pathways.

Structure, Property, and Performance of Catalyst Layers in Proton Exchange Membrane Fuel Cells.

Catalyst layer (CL) is the core component of proton exchange membrane (PEM) fuel cells, which determines the performance, durability, and cost. However, difficulties remain for a thorough understanding of the CLs' inhomogeneous structure, and its impact on the physicochemical and electrochemical properties, operating performance, and durability. The inhomogeneous structure of the CLs is formed during the manufacturing process, which is sensitive to the associated materials, composition, fabrication methods, procedures, and conditions. The state-of-the-art visualization and characterization techniques are crucial to examine the CL structure. The structure-dependent physicochemical and electrochemical properties are then thoroughly scrutinized in terms of fundamental concepts, theories, and recent progress in advanced experimental techniques. The relation between the CL structure and the associated effective properties is also examined based on experimental and theoretical findings. Recent studies indicated that the CL inhomogeneous structure also strongly affects the performance and degradation of the whole fuel cell, and thus, the interconnection between the fuel cell performance, failure modes, and CL structure is comprehensively reviewed. An analytical model is established to understand the effect of the CL structure on the effective properties, performance, and durability of the PEM fuel cells. Finally, the challenges and prospects of the CL structure-associated studies are highlighted for the development of high-performing PEM fuel cells.

Developing a RiskS-core Model based on Angiogenesis-related lncRNAs for Colon Adenocarcinoma Prognostic Prediction.

AIM: We screened key angiogenesis-related lncRNAs based on colon adenocarcinoma (COAD) to construct a RiskS-core model for predicting COAD prognosis and help reveal the pathogenesis of the COAD as well as optimize clinical treatment. BACKGROUND: Regulatory roles of lncRNAs in tumor progression and prognosis have been confirmed, but few studies have probed into the role of angiogenesis-related lncRNAs in COAD. OBJECTIVE: To identify key angiogenesis-related lncRNAs and build a RiskS-core model to predict the survival probability of COAD patients and help optimize clinical treatment. METHODS: Sample data were collected from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database. The HALLMARK pathway score in the samples was calculated using the single sample gene set enrichment analysis (ssGSEA) method. LncRNAs associated with angiogenesis were filtered by an integrated pipeline algorithm. LncRNA-based subtypes were classified by ConsensusClusterPlus and then compared with other established subtypes. A RiskS-core model was created based on univariate Cox, least absolute shrinkage and selection operator (LASSO) regression and stepwise regression analysis. The Kaplan-Meier curve was drawn by applying R package survival. The time-dependent ROC curves were drawn by the timeROC package. Finally, immunotherapy benefits and drug sensitivity were analyzed using tumor immune dysfunction and exclusion (TIDE) software and pRRophetic package. RESULTS: Pathway analysis showed that the angiogenesis pathway was a risk factor affecting the prognosis of COAD patients. A total of 66 lncRNAs associated with angiogenesis were screened, and three molecular subtypes (S1, S2, S3) were obtained. The prognosis of S1 and S2 was better than that of S3. Compared with the existing subtypes, the S3 subtype was significantly different from the other two subtypes. Immunoassay showed that immune cell scores of the S2 subtype were lower than those of the S1 and S3 subtypes, which also had the highest TIDE scores. We recruited 8 key lncRNAs to develop a RiskS-core model. The high RiskS-core group with inferior survival and higher TIDE scores was predicted to benefit limitedly from immunotherapy, but it may be more sensitive to chemotherapeutics. A nomogram designed by RiskS-core signature and other clinicopathological characteristics shed light on rational predictive power for COAD treatment. CONCLUSION: We constructed a RiskS-core model based on angiogenesis-related lncRNAs, which could serve as potential prognostic predictors for COAD patients and may offer clues for the intervention of anti-angiogenic application. Our results may help evaluate the prognosis of COAD and provide better treatment strategies.

Occurrence and phase distribution of lipophilic marine algal toxins in the bottom boundary layer and sediment-porewater system of two mariculture sites.

To date, understanding the fate of lipophilic marine algal toxins (LMATs) in benthic environments on which cultivated shellfish depend is still limited. In this work, the occurrence, concentration levels, and phase distributions of LMATs in the benthic environments of two mariculture sites (Sishili and Rongcheng Bays) in China were investigated for the first time. Five LMATs: okadaic acid (OA), pectenotoxin-2 (PTX2), gymnodimine, 13-desmethyl spirolide C, and azaspiracid-2 (AZA2) and three derivatives: dinophysistoxin-1 isomer (DTX1-iso), pectenotoxin-2 seco acid, and 7-epi- pectenotoxin-2 seco acid were detected in different environmental samples. OA and PTX2 were the dominant LMATs in the bottom boundary layer (BBL) and sediment, whereas AZA2 was present in the sediment only. Notably, DTX1-iso was found for the first time to be widely distributed in the benthic environments of the bays. In BBL, the average proportion of LMATs in the dissolved phase (99.20%) was much higher than in the particulate phase (0.80%). Partition of LMATs was more balanced between sediment porewater (57.80% average proportion) and sediment (42.20%). The concentrations of ∑LMATs in the BBL seawater ranged from 19.09 ng/L to 41.57 ng/L (mean of 32.67 ng/L), and the spatial distribution trend was higher in offshore than nearshore. ∑LMATs concentrations in the sediment and porewater of the two bays ranged from 17.04 ng/kg to 150.13 ng/kg (mean of 53.58 ng/kg) and from 8.29 ng/L to 120.58 ng/L (mean of 46.63 ng/L), respectively. Their spatial distributions differed from those in BBL, showing a trend of high concentrations in areas with heavy land-based inputs. ∑LMATs concentrations in porewater were significantly higher than those in BBL seawaters, suggesting that the potential hazards of LMATs to benthic organisms may be underestimated.

[Distribution, Sources, and Risk Assessment of Microplastics in Surface Sediments of Yellow River Delta Wetland].

Estuarine habitats are a critical zone of the Earth with strong land-sea interactions, that are strongly influenced by human activities. Microplastics (MPs) pollution in the Yellow River Delta (YRD) wetland, a typical young warm-temperate estuarine wetland, has not been comprehensively studied. The morphology, abundance, particle size, and polymer composition of MPs in the surface sediments of the YRD wetland were determined, and the pollution status and ecological risk in the study area were evaluated using the pollution load index (PLI) and potential pollution risk index (PRI). The results showed that the abundance of MPs in the YRD wetland was 20-520 n·kg-1, with a median value of 150 n·kg-1. The MPs were primarily fibers in shape and black in color, with particle size over 1 mm. The polymer components were primarily rayon, polyethylene, polyester, and polyethylene terephthalate. The PLI and PRI values of the MPs in the area were between 0.04-0.96 and 0.00-171.60, respectively, indicating that the pollution of MPs in the YRD wetland was at a slightly polluted level with low ecological risk.