Opposite response of constructed wetland performance in nitrogen and phosphorus removal to short and long terms of operation.

Constructed wetlands (CWs) have been widely used for treating polluted water since the 1950s, with applications in over 50 countries worldwide. Most studies investigating the pollutant removal efficiency of these wetlands have focused on differences among wetland designs, operation strategies, and environmental conditions. However, there still remains a gap in understanding the variation in wetland pollutant removal efficiency over different time scales. Therefore, the main aim of the study is to address this gap by conducting a global meta-analysis to estimate the variation in nitrogen (N) and phosphorus (P) removal by wetland in short- and long-term pollutant treatment. The findings of this study indicated that the total efficiencies of N and P removal increased during short-term wetland operation but decreased during long-term operation. However, for surface flow CWs specifically, the efficiencies of N and P removal increased during short-term operation and remained stable during long-term operation. Moreover, the study discovered that wetland N removal efficiency was influenced by seasons, with an increase in spring and summer and a decrease in autumn and winter. Conversely, there was no significant seasonal effect on P removal efficiency. Additionally, high hydraulic load impaired wetland N and P removal efficiency during long-term operation. This study offers a critical review of the role of wetlands in wastewater treatment and provides valuable reference data for the design and selection of CWs types during wastewater treatment in the aspect of sustainability.

[Quantification of antigen of Mycoplasma capricolum subsp. capripneumoniae by optical assay].

Mycoplasma capricolum subsp. capripneumoniae (Mccp) is the cause of contagious caprine pleuropneumonia (CCPP) in goats. Inactivated vaccines and capsular polysaccharide (CPS) indirect hemagglutination reagents are available for prevention and serological detection, but high culture costs and complex antigen quantification have been plagued by production staff. In order to solve these problems in production practice, a sugar fermentation medium with an initial pH value of 7.8, which could improve the production of two antigens simultaneously, was screened out by changing the initial pH value based on previous Mccp metabolomics analysis. Since phenol red can be identified by UV absorption spectrum and cetyltrimethylammonium bromide (CTAB) can bind to anionic capsular polysaccharide, a UV spectrum measurement method for analyzing the culture stage reached by Mccp and a CTAB precipitation test for relative quantification of capsular polysaccharide antigen content in the fermentation broth were established. The UV spectrum observation method can guide the production of Mccp according to the growth curve of Mccp, which greatly reduces the monitoring time of the traditional CCU method and improves the accuracy of the original eye-observation method. The established CTAB precipitation test can complete the monitoring of CPS content within 5 hours, which greatly reduces the time required compared with the traditional differential technique, and its accuracy was verified by the phenol-sulfuric acid method. The optimized culture medium and the two correlation comparison methods established in this study can effectively reduce the production cost of Mccp and improve the production efficiency. The two assays have been used in the research at our laboratory, which provides experimental data for further improvement of the production process of CCPP inactivated vaccine and capsular polysaccharide as well as rapid quantification.

Plant Traits Guide Species Selection in Vegetation Restoration for Soil and Water Conservation.

Great efforts have been made to improve the soil and water conservation capacity by restoring plant communities in different climatic and land-use types. However, how to select suitable species from local species pools that not only adapt to different site environments, but also achieve certain soil and water conservation capacities is a great challenge in vegetation restoration for practitioners and scientists. So far, little attention has been paid to plant functional response and effect traits related to environment resource and ecosystem functions. In this study, together with soil properties and ecohydrological functions, we measured the seven plant functional traits for the most common species in different restoration communities in a subtropical mountain ecosystem. Multivariate optimization analyses were performed to identify the functional effect types and functional response types based on specific plant traits. We found that the community-weighted means of traits differed significantly among the four community types, and the plant functional traits were strongly linked with soil physicochemical properties and ecohydrological functions. Based on three optimal effect traits (specific leaf area, leaf size, and specific root length) and two response traits (specific leaf area and leaf nitrogen concentration), seven functional effect types in relation to the soil and water conservation capacity (interception of canopy and stemflow, maximum water-holding capacity of litter, maximum water-holding capacity of soil, soil surface runoff, and soil erosion) and two plant functional response types to soil physicochemical properties were identified. The redundancy analysis showed that the sum of all canonical eigenvalues only accounted for 21.6% of the variation in functional response types, which suggests that community effects on soil and water conservation cannot explain the overall structure of community responses related to soil resources. The eight overlapping species between the plant functional response types and functional effect types were ultimately selected as the key species for vegetation restoration. Based on the above results, we offer an ecological basis for choosing the appropriate species based on functional traits, which may be very helpful for practitioners involved in ecological restoration and management.

Soil Moisture and Available Phosphorus as the Factors Driving Variation in Functional Characteristics across Different Restoration Communities in a Subtropical Mountain Ecosystem.

Functional characteristics are increasingly used to evaluate the success of different vegetation restoration. Community functional diversity (FD) and the community-weighted mean (CWM), as two main complementary components, are closely linked to site environment and ecosystem functions. However, the patterns and driving factors of functional characteristics are still not clear in different vegetation restoration types. Here, four community restoration types (secondary shrubland, SL; Pinus yunnanensis forest, PF; mixed needle-broad-leaved forest, MF; natural secondary forest, NSF) were selected to investigate species diversity, FD, CWM, and soil physicochemical properties. The relative effects of species diversity and soil abiotic features on variation in functional characteristics were then evaluated. We found that different restoration communities altered most community structures and functional properties in terms of species diversity, FD, and CWM. CWM values and FD in different communities presented different distribution patterns depending on certain traits and parameters. Significant correlations between functional traits were found at the species and community scales, suggesting a potential covariation between these selected traits in communities. The results of redundancy analysis and variation partitioning showed that most of the variation in functional characteristics, especially CWM, was explained by soil moisture and available phosphorus, indicating that habitat filters regulate the functional characteristics of plant communities mainly by changing the dominant species composition and functional traits of species. Therefore, the selection of restoration species adapted to low soil moisture and available phosphorus and the construction of communities based on selected species as the dominant species can effectively drive community assembly and ecosystem functions in the vegetation restoration process.

OmpA is involved in the invasion of duck brain microvascular endothelial cells by Riemerella anatipestifer.

Bacterial meningitis is a major cause of morbidity and mortality. Despite advances in antimicrobial chemotherapy, the disease remains detrimental to humans, livestock, and poultry. Riemerella anatipestifer is a gram-negative bacterium causing duckling serositis and meningitis. However, the virulence factors contributing to its binding and invasion of duck brain microvascular endothelial cells (DBMECs) and penetration of the blood-brain barrier (BBB) have never been reported. In this study, immortalized DBMECs were successfully generated and used as an in vitro-model of duck BBB. Furthermore, ompA gene deletion mutant of the pathogen and multiple complemented strains carrying the complete ompA gene and its truncated forms were constructed. Bacterial growth, invasion, and adhesion assays and animal experiments were performed. The results show that the OmpA protein of R. anatipestifer had no effect on bacterial growth and adhesion ability to DBMECs. The role of OmpA in the invasion of R. anatipestifer into DBMECs and duckling BBB was confirmed. The amino acids 230-242 of OmpA represents a key domain involved in R. anatipestifer invasion. In addition, another OmpA1164 protein constituted by the amino acids 102-488 within OmpA could function as a complete OmpA. The signal peptide sequence from amino acids 1-21 had no significant effect on OmpA functions. In conclusion, this study illustrated that OmpA is an important virulence factor mediating R. anatipestifer invasion of DBMECs and penetration of the duckling BBB.

Aerodynamics of the Wells turbine with a Hawkmoth-inspired blade design.

This work introduces a new biomimetic design for the well-known Wells turbine to enhance its efficiency for harvesting energy. In this paper, a biomimetic Wells turbine inspired by the geometry of hawkmoth wings is presented. Aerodynamics of both the bio-inspired design and the conventional design are investigated through computational fluid dynamics. Non-dimensional performance indicators of the bio-inspired design are compared to those of the conventional turbine, including the torque coefficient, the pressure drop coefficient, the turbine efficiency. The velocity and pressure distribution as well as the vortices shed from the blades are illustrated to understand the differences in flow phenomena. The results indicate that the biomimetic design changes the flow field and can attain a higher peak efficiency, especially at high angle of attack. Finally, the performance of blades with various aspect ratios is investigated to better understand the biomimetic design.

EFFECT OF YISHENJIANPI RECIPE ON SEMEN QUALITY AND SPERM MITOCHONDRIA IN MICE WITH OLIGOASTHENOZOOSPERMIA INDUCED BY TRIPTERYGIUM GLYCOSIDES.

BACKGROUND: Kidney tonifying - spleen strengthening method being one of the modalities for treatment of astheno-oligozoospermia is currently commonly used in the clinical setting. To investigate the mechanism of YiShenJianPi (YSJP) Recipe, used in Traditional Chinese Medicine to benefit "the kidney" and strengthen "the spleen". MATERIALS AND METHODS: Oligoasthenozoospermia, male BALB/c mice were randomly divided into normal control, disease model, positive control, low-dosage and high-dosage groups. Oligoasthenozoospermia was induced by tripterygium glucosides intragastric administration before treatment started. Through using computer-aided sperm analysis to test the changes in sperm quality, utilizing flow cytometry to test the percentage of sperm with normal mitochondrial transmembrane potential (JC-1 + %), utilizing X-ray microscopy to observe epididymal sperm ultra-microstructure placing special emphasis and photographing the differences in mitochondria of the flagellum region. RESULTS: Compared with DM, sperm quality of the treated mice was significantly better (P<0.05, respectively). Compared with PC, the LD group had significantly better quality sperms, while the parameters in the HD group were numerically better. Compared with NC, all other groups had significantly lower percentage of sperms with normal mitochondrial membrane potential. In PC, LD and HD groups, the percentage of sperms with normal mitochondrial membrane potential was significantly higher than that of D. The 9+9+2 mitochondrial sheath structure was complete in NC but damaged in DM. In the treatment groups, this structure was fairly clear. CONCLUSION: YSJP improved semen quality with oligoasthenozoospermia by improving sperm mitochondrial membrane potential and restoring sperm mitochondrial ultrastructure.