Integrated evaluation of the impact of water diversion on water quality index and phytoplankton assemblages of eutrophic lake: A case study of Yilong Lake.

Water diversion has been widely utilized to enhance lake water quality and mitigate cyanobacterial blooms. However, previous studies have mainly focused on investigating the effects of water diversion on water quality or aquatic ecological health. Consequently, there is limited research investigating the combined impact of water diversion on the water quality and the ecological health of eutrophic lakes, and whether the WQI and phytoplankton assemblages demonstrate similar patterns following water diversion. In this study, the effects of water diversion on the ecosystem health of eutrophic lakes were comprehensively evaluated based on the WQI indices and phytoplankton assemblages during the NWDP-21 and WDP-22. The results showed that the annual mean of WQI increased from 52.02 to 54.36 after water diversion, which improved the water quality of the lake, especially NH3-N and TN decreased by 58.6% and 15.2%, respectively. The phytoplankton assemblages changed significantly before and after water diversion, and we observed that the total biomass of phytoplankton decreased by 12.3% and phytoplankton diversity indices (Shannon-Wiener diversity, Pielou evenness, and Simpson index) increased by 8.6%-8.9% after water diversion, with an improvement in the connectivity and stability of the phytoplankton. Notably, enhanced adaptations of rare sub-communities for resource use in water diversion environments, and water diversion inhibited the dispersal ability of dominant functional groups, and the effects of hydrological disturbances on the structure of phytoplankton assemblage favored the ecological health of eutrophic lakes. VPA analysis further reveals that water diversion alters the drivers of phytoplankton functional group biomass and phytoplankton diversity. The results of the PLS-PM analysis clarify that water diversion indirectly impacts the total phytoplankton biomass and phytoplankton diversity primarily by modifying light availability. Significant correlations are observed between the dominant functional groups biomass and diversity indices of WQI. The trends in changes observed in water quality indices and phytoplankton following water diversion align with the evaluation of water ecological health. This study provides valuable guidance for the ecological management of the diversion project in Yilong Lake and serves as a reference for similar projects in other lakes.

Comprehensive Analyses of Four PhNF-YC Genes from Petunia hybrida and Impacts on Flowering Time.

Nuclear Factor Y (NF-Y) is a class of heterotrimeric transcription factors composed of three subunits: NF-A, NF-YB, and NF-YC. NF-YC family members play crucial roles in various developmental processes, particularly in the regulation of flowering time. However, their functions in petunia remain poorly understood. In this study, we isolated four PhNF-YC genes from petunia and confirmed their subcellular localization in both the nucleus and cytoplasm. We analyzed the transcript abundance of all four PhNF-YC genes and found that PhNF-YC2 and PhNF-YC4 were highly expressed in apical buds and leaves, with their transcript levels decreasing before flower bud differentiation. Silencing PhNF-YC2 using VIGS resulted in a delayed flowering time and reduced chlorophyll content, while PhNF-YC4-silenced plants only exhibited a delayed flowering time. Furthermore, we detected the transcript abundance of flowering-related genes involved in different signaling pathways and found that PhCO, PhGI, PhFBP21, PhGA20ox4, and PhSPL9b were regulated by both PhNF-YC2 and PhNF-YC4. Additionally, the transcript abundance of PhSPL2, PhSPL3, and PhSPL4 increased only in PhNF-YC2-silenced plants. Overall, these results provide evidence that PhNF-YC2 and PhNF-YC4 negatively regulate flowering time in petunia by modulating a series of flowering-related genes.

A Polytetrafluoroethylene-Based Solvent-Free Procedure for the Manufacturing of Lithium-Ion Batteries.

Lithium-ion batteries (LIBs) have recently become popular for energy storage due to their high energy density, storage capacity, and long-term cycle life. Although binders make up only a small proportion of LIBs, they have become the key to promoting the transformation of the battery preparation process. Along with the development of binders, the battery manufacturing process has evolved from the conventional slurry-casting (SC) process to a more attractive solvent-free (SF) method. Compared with traditional LIBs manufacturing method, the SF method could dramatically reduce and increase the energy density due to the reduced preparation steps and enhanced electrode loading. Polytetrafluoroethylene (PTFE), as a typical binder, has played an important role in fabricating high-performance LIBs, particularly in regards to the SF technique. In this paper, the development history and application status of PTFE binder was introduced, and then its contributions and the inherent problems involved in the SF process were described and analyzed. Finally, the viewpoints concerning the future trends for PTFE-based SF manufacturing methods were also discussed. We hope this work can inspire future research concerning high-quality SF binders and assist in promoting the evolution of the SF manufacturing technology in regards to LIBs.

Optimal Growth Conditions for Forming c-Axis (002) Aluminum Nitride Thin Films as a Buffer Layer for Hexagonal Gallium Nitride Thin Films Produced with In Situ Continual Radio Frequency Sputtering.

Aluminum nitride (AlN) thin-film materials possess a wide energy gap; thus, they are suitable for use in various optoelectronic devices. In this study, AlN thin films were deposited using radio frequency magnetron sputtering with an Al sputtering target and N2 as the reactive gas. The N2 working gas flow rate was varied among 20, 30, and 40 sccm to optimize the AlN thin film growth. The optimal AlN thin film was produced with 40 sccm N2 flow at 500 W under 100% N2 gas and at 600 °C. The films were studied using X-ray diffraction and had (002) phase orientation. X-ray photoelectron spectroscopy was used to determine the atomic content of the optimal film to be Al, 32%; N, 52%; and O, 12% at 100 nm beneath the surface of the thin film. The film was also investigated through atomic force microscopy and had a root mean square roughness of 2.57 nm and a hardness of 76.21 GPa. Finally, in situ continual sputtering was used to produce a gallium nitride (GaN) layer on Si with the AlN thin film as a buffer layer. The AlN thin films investigated in this study have excellent material properties, and the proposed process could be a less expensive method of growing high-quality GaN thin films for various applications in GaN-based power transistors and Si integrated circuits.

A siamese network-based approach for vehicle pose estimation.

We propose a deep learning-based vehicle pose estimation method based on a monocular camera called FPN PoseEstimateNet. The FPN PoseEstimateNet consists of a feature extractor and a pose calculate network. The feature extractor is based on Siamese network and a feature pyramid network (FPN) is adopted to deal with feature scales. Through the feature extractor, a correlation matrix between the input images is obtained for feature matching. With the time interval as the label, the feature extractor can be trained independently of the pose calculate network. On the basis of the correlation matrix and the standard matrix, the vehicle pose changes can be predicted by the pose calculate network. Results show that the network runs at a speed of 6 FPS, and the parameter size is 101.6 M. In different sequences, the angle error is within 8.26° and the maximum translation error is within 31.55 m.

A Time Sequence Images Matching Method Based on the Siamese Network.

The similar analysis of time sequence images to achieve image matching is a foundation of tasks in dynamic environments, such as multi-object tracking and dynamic gesture recognition. Therefore, we propose a matching method of time sequence images based on the Siamese network. Inspired by comparative learning, two different comparative parts are designed and embedded in the network. The first part makes a comparison between the input image pairs to generate the correlation matrix. The second part compares the correlation matrix, which is the output of the first comparison part, with a template, in order to calculate the similarity. The improved loss function is used to constrain the image matching and similarity calculation. After experimental verification, we found that it not only performs better, but also has some ability to estimate the camera pose.

One-pot synthesis of cobalt complexes with 2,6-bis(arylimino)phenoxyl/phenthioxyl ligands and catalysis on isoprene polymerization.

Several cobalt complexes supported by 2,6-bis(arylimino)phenoxyl/phenthioxyl ligands κ2N,X-Ar[NXN]CoCl(THF) (1a, X = O, Ar = 2,6-Me2C6H3; 1b, X = O, Ar = 2,6-iPr2C6H3; 2a, X = S, Ar = 2,6-Me2C6H3; 2b, X = S, Ar = 2,6-iPr2C6H3) were synthesized by direct oxygen(sulfur) insertion into the C-Co bond of the mixed-valence cobalt complexes {κ2C,N,η6-Ar[NCN]Co-κN-CoCl(µ-Cl)}2. Crystallization of 1b in the presence of water gave the hydrolysis product 1b'. Treatment of Ar[NCN]Li with dioxygen followed by the addition of CoCl2 afforded the heteroatomic complexes {κ2N,O-Ar[NON]Co(µ-Cl)2Li}2 (3a, Ar = 2,6-Me2C6H3; 3b, Ar = 2,6-iPr2C6H3) or κ2N,O-Ar[NON]Co2Cl2(µ-Cl)2Li(THF)2 (4a, Ar = 2,6-Me2C6H3; 4b, Ar = 2,6-iPr2C6H3) depending on the amount of CoCl2 used. The Co(iii)/Li heterometallic complex 3b' with imino-phenoxyl-amino ligands was formed probably via a redox reaction of 3b. The reactions of Ar[NCN]Li with elemental sulfur and CoCl2 gave κ2N,S-Ar[NSN]Co2Cl2(µ-Cl)2Li(THF)2 (5a, Ar = 2,6-Me2C6H3; 5b, Ar = 2,6-iPr2C6H3) respectively. These complexes were well characterized by FT-IR and elemental analyses, and the molecular structures of 1b', 3b', 4a, and 4b were confirmed by X-ray crystallography. Upon activation with Al2Et3Cl3 in toluene, these complexes showed high activities in isoprene polymerization affording cis-1,4 enriched polymers with a moderate molecular weight (0.85-4.72 × 104 Da).

Environmental factors associated with cyanobacterial assemblages in a mesotrophic subtropical plateau lake: A focus on bloom toxicity.

Harmful algal blooms caused by cyanobacteria have been increasing in frequency worldwide. However, the main environmental drivers of this change are often difficult to identify because of the effects of the interaction between eutrophication and climate change. Recently, filamentous N2-fixing cyanobacteria and non-diazotrophic Microcystis have been observed to be co-existing and undergoing succession in some eutrophic lakes. However, the succession patterns of dominant cyanobacteria and the factors driving this in mesotrophic lakes are not well understood. We hypothesized that the changes in cyanobacterial assemblages in mesotrophic lakes could result in a relatively high risks of toxic blooms, and that these changes are associated with the global climatic changes. We tested these hypotheses using data from the subtropical mesotrophic Lake Erhai. We found that the high spatiotemporal variability in the cyanobacterial community, and the increase in biomass were driven primarily by the growth of bloom-forming cyanobacterial taxa. Species-specific biomasses were related to a different environmental stressor; increases in dissolved organic carbon (DOC) concentrations were statistically associated with an increase of Microcystis biomass, whereas increases in surface water temperature favored higher biomass of Pseudanabaena at low transparency and high concentration of phosphorus. In addition, low nitrogen- to- phosphorus ratios were identified as potential determinants of the abundance of N2-fixing Dolichospermum. Furthermore, changes in the concentration of DOC, total nitrogen, pH and water transparency levels were found to affect the composition of Microcystis morphotypes and genotypes mostly. This study highlights that the toxic to non-toxic Microcystis ratio might increase with the water darkening and browning (which occurs in many subtropical plateau lakes). Lake management strategies, therefore, need to consider the toxicity of cyanobacterial assemblages in mesotrophic lakes over the intensity of the cyanobacterial blooms.

Contact tracing of syphilis-seropositive pregnant women and syphilis-infection among their male partners in Bao'an district, Shenzhen, China.

BACKGROUND: Untreated male partners are a critical source of maternal re-infection. Contact tracing is a good way to identify infection among partners and reduce risk of mother-to-child transmission related to maternal re-infection. This study aimed to analyze the current situation and related factors of contact tracing of syphilis-seropositive pregnant women and syphilis-infection among their male partners. METHOD: Data of syphilis-seropositive pregnant women and their male partners attending clinic for syphilis-screening were obtained from the Shenzhen Program for Prevention of Congenital Syphilis. Contact tracing rate of syphilis-seropositive pregnant women and syphilis prevalence among male partners were counted, and related factors were also analyzed using a random-effects logistic regression model. RESULT: Of the 1299 syphilis-seropositive pregnant women, 74.1% (963/1299) had their male partners receiving syphilis-screening and 19.1% (184/963) of male partners were syphilis-infected. For pregnant women, being divorced (adjusted odds ratio [AOR] =0.39; 95%CI: 0.17-0.87), seeking for emergency services at their first antenatal clinics visits (AOR = 0.58; 95%CI: 0.44-0.77), reporting willingness to notify partner(AOR = 7.65; 95%CI: 4.69-12.49), multi-partners (AOR = 1.38; 95%CI:1.03-1.86) and having a history of drug abuse (AOR = 0.37; 95%CI: 0.14-1.00)were independently associated with successful contact tracing. For male partners, of minority ethnicity (AOR = 4.15; 95%CI: 1.66-10.34), age at first sex>20(AOR = 0.57; 95%CI: 0.37-0.87), reporting multi-partners (AOR = 1.60; 95%CI: 1.04-2.46), having a history of drug abuse (AOR = 4.07; 95%CI: 1.31-12.64) were independently associated with syphilis-infection. In addition, pregnant women with TRUST titer ≥1:8 (AOR = 2.81; 95%CI: 1.87-4.21), having a history of adverse pregnancy outcomes (AOR = 1.70; 95%CI: 1.14-2.53), reporting multi-partners (AOR = 0.43; 95%CI: 0.29-0.64) and reporting the current partner as the source of syphilis (AOR = 5.05; 95%CI: 2.82-9.03) were independently associated with partners' syphilis-infection. CONCLUSION: Contact tracing is feasible and effective in identifying syphilis-infected partners among syphilis-seropositive pregnant women. Contact tracing is associated with many factors such as women's marital status, services at their first antenatal clinics visit and willingness of partner notification. Partners' ethnicity, age at first sex, multi-partners and history of drug abuse as well as women's levels of TRUST titer were associated with partners' syphilis-infection.

Influence of product volume on water antimicrobial efficacy and cross-contamination during retail batch washing of lettuce.

Fresh produce shall be thoroughly washed at the retail level prior to serving to the consumer with potable water. Foodborne pathogens if present on a product may transfer to the wash water and cross-contaminate other products immersed in the water. Typically, an entire carton of lettuce (24 heads) is washed together increasing the likelihood of cross-contamination due to the close contact between each head. This study aimed to compare the effects of two wash batch volumes - "low" (8 heads) and "high" (24 heads) on the efficacy of two commercial water antimicrobials and cross-contamination. Red leaf lettuce was spot-inoculated (~5.0 log CFU/g) with Shiga toxin-producing Escherichia coli (STEC) and Listeria monocytogenes. In the first batch of washing, inoculated lettuce was washed with non-inoculated lettuce, followed by reuse of the water/antimicrobials twice washing only non-inoculated lettuce. Samples of inoculated and non-inoculated lettuce were collected to determine aerobic plate count (APC) as well as the populations of STEC and L. monocytogenes. Microbiological analysis of the wash water was also conducted. Wash volume (8 versus 24 lettuce heads) had limited effects on the antimicrobial activities of the interventions evaluated. Instead, high-volume wash increased the rate of cross-contamination between non-inoculated and inoculated lettuce, and cross-contamination of non-inoculated lettuce through wash water reuse. Retailers should consider volume of product processed per batch, reuse of wash water, and use of an appropriate water antimicrobial in consideration of mitigating potential product cross-contamination.

Bis(imino)aryl NCN pincer cobalt complexes: synthesis and disproportionation.

Treatment of iPr[NCN]Br (2,6-(2,6-iPr2C6H3C[double bond, length as m-dash]N)2C6H3Br) with nBuLi in THF and the subsequent addition of 1 equiv. of CoCl2, CoCl2(Ph3P)2, and CoBr2 gave pincer Co(ii) complexes {iPr[NCN]Co(µ-Cl)}2 (1d), iPr[NCN]CoClPh3P (1d-Ph3P), and iPr[NCN]CoBr2·Li(THF)4 (1d-LiBr) respectively in moderate yields, whereas the slow addition of in situ prepared iPr[NCN]Li to CoCl2 in THF afforded an unexpected mixed-valence cobalt(i/ii) complex κ2C,N,η6-iPr[NCN]Co-κN-CoCl3·Li(THF)4 (2d). Complex 2d was probably formed via a disproportionation reaction of the iPr[NCN]Co(ii) species with excess CoCl2 during the reaction. Nevertheless, addition of CoCl2 to in situ formed 1d-THF at room temperature did not lead to 2d but gave a trinuclear Co(ii) complex {iPr[NCN]Co(µ-Cl)(µ-Br/Cl)}2Co (1d-CoCl2) in moderate yield. Similar reactions using ligands containing small ortho groups in the imine moieties R[NCN]Br (2,6-(2,6-Me2C6H3C[double bond, length as m-dash]N)2C6H3Br, Me[NCN]Br; 2,6-(2,6-Et2C6H3C[double bond, length as m-dash]N)2C6H3Br, Et[NCN]Br; 2,6-(2,4,6-Me3C6H2C[double bond, length as m-dash]N)2C6H3Br, Mes[NCN]Br) and CoBr2, regardless of the reactant addition sequence, afforded mixed-valence cobalt(i/ii) complexes {κ2C,N,η6-R[NCN]Co-κN-CoBr(µ-Br)}2 (Me[NCN] (2a), Et[NCN] (2b), and Mes[NCN] (2c)), suggesting that the bulkiness of the ortho-groups in the imine moieties of the ligands plays an important role in the disproportionation reaction. In the presence of PMe3, Co(ii) complexes κ2C,N-R[NCN]CoBr(PMe3)2 (3a-d) and a bisligated cobalt(ii) complex κ3N,C,N-κ2C,N-iPr[NCN]2CoPMe3 (4d) can be prepared respectively in high yields. The molecular structures of 1d-LiBr, 1d-CoCl2, 2b, 2d, 3a, and 4d were confirmed by X-ray crystallographic analysis and the detailed mechanisms of the disproportionation reaction were proposed.

A nanostructured MoO2/MoS2/MoP heterojunction electrocatalyst for the hydrogen evolution reaction.

Electrocatalytic production of hydrogen from water is considered to be a promising and sustainable strategy. In this work, the low-cost nanostructured MoO2/MoS2/MoP heterojunction is successfully synthesized by phosphorization of the pre-prepared urchin-like MoO2/MoS2 nanospheres as the stable, highly efficient electrocatalysis for the hydrogen evolution reaction (HER). The MoO2/MoS2/MoP-800 (MoO2/MoS2 nanospheres are phosphated at 800 °C) displays a catalytic ability for the HER with an overpotential of 135 mV to achieve 10 mA cm-2 and a Tafel slope of 67 mV dec-1 in 0.5 M H2SO4, which is superior to MoO2/MoS2 nanospheres (200 °C; 24 h), MoO2/MoS2/MoP-700 (MoO2/MoS2 nanospheres are phosphated at 700 °C) and MoO2/MoS2/MoP-900 (MoO2/MoS2 nanospheres are phosphated at 900 °C). Meanwhile, the catalyst exhibits superior properties for HER with an overpotential of 145 mV to achieve 10 mA cm-2 and a Tafel slope of 71 mV dec-1 in 1 M KOH solution. Detailed characterizations reveal that the improved HER performances are significantly related to P-doping and the spherical nanostructure. This work not only provides a low-cost selective for electrocatalytic production of hydrogen, but also serves as a guide to optimize the composition and structure of nanocomposites.

Extremely sensitive and accurate H2S sensor at room temperature fabricated with In-doped Co3O4 porous nanosheets.

A facile hydrothermal method to prepare In-doped Co3O4 porous nanosheets is reported in this paper for the first time. The prepared samples were made into gas sensors, and their sensing properties, such as response, response time, recovery time, selectivity and stability, have been researched systematically. These results indicate that the sensor fabricated with 1.0 at% In-doped Co3O4 porous nanosheets shows a high response of 6.81 to 50 ppm and an obvious response of 1.4 to 1 ppm H2S. What's more, this sensor exhibited a high selectivity and outstanding long-term stability toward H2S. The excellent gas sensing performance was mainly ascribed to two reasons. (i) Doping with In increases the concentration of charge carriers, oxygen-deficient regions and the chemisorbed oxygen, which enhances the gas response. (ii) The rough porous structure is conducive to gas adsorption and capture, and provides many active sites for the sensing reaction. Therefore, 1.0 at% In-doped Co3O4 porous nanosheets could be used as a sensing material in future applications.

Isolation and characterization of a highly pathogenic strain of Porcine enteric alphacoronavirus causing watery diarrhoea and high mortality in newborn piglets.

Porcine enteric alphacoronavirus (PEAV) was first discovered in China in February 2017, and the origin and virulence of this novel porcine coronavirus were not fully characterized. Here, we isolated a strain of PEAV, named GDS04 that is identified by immunofluorescence and typical crown-shaped particles observed with electron microscopy. Genomic analysis reveals that PEAV GDS04 shares a close relationship with SADS-CoV and SeACoV. Furthermore, newborn piglets orally challenged with PEAV GDS04 developed typical clinical symptoms as watery diarrhoea in neonatal piglets. Viral RNA was detected in faeces and various tissues of the infected piglets. Moreover, macroscopic and microscopic lesions in whole intestinal tract were observed, and viral antigen could be detected in the small intestines by immunohistochemical staining and electron microscopy. Importantly, the mortality rate of inoculated-newborn piglets was 100% and half of the cohabiting piglets died. Collectively, we demonstrate that PEAV is highly pathogenic in newborn piglets.

Influence of water antimicrobials and storage conditions on inactivating MS2 bacteriophage on strawberries.

Foodborne illnesses caused by norovirus contaminated fresh produce remain a food safety concern worldwide. In the present study, the impacts of commercial and home processing conditions of strawberries were evaluated for inactivation of the MS2 bacteriophage. MS2 was used as a surrogate of norovirus and was spot inoculated onto strawberries to achieve 6.6 log PFU/g. The inoculated strawberries were washed with tap water, electrolyzed water, or 50 ppm chlorine for 90 s prior to and after storage. After initial washing, the strawberries were separately stored at -20 °C and -80 °C for 30 days. Change in MS2 populations on strawberries was evaluated by plaque assay method on day 1, 15, and 30 for -20 °C and -80 °C groups. The results showed that washing strawberries prior to storage resulted in a significant decrease (approximately 1 log PFU/g) of MS2 population regardless of the treatment (p < 0.05). Frozen storage had minor effects on inactivating MS2, which resulted in approximately a 0.5 log PFU/g reduction at the end of storage. Washing frozen berries in electrolyzed water or 50 ppm chlorine on day 30 resulted in an additional 1 log PFU/g decrease in MS2 compared to water alone. These results suggest that washing strawberries with a chemical antimicrobial prior to and post frozen storage may enhance microbial safety.

Seasonal and spatial distributions of euphotic zone and long-term variations in water transparency in a clear oligotrophic Lake Fuxian, China.

To assess the seasonal and spatial variations and long-term trends in water optical properties in Lake Fuxian, investigations based on field work in four seasons and a long-term analysis of data from 1980 to 2014 were conducted. The results show that there was no significant variation in the euphotic depth (Zeu) across the four seasons, and no significant correlations between Zeu and potential influencing factors in seasons other than summer, suggesting that the water itself may be a major factor regulating the Zeu in general. Nevertheless, significant differences in Zeu between the north region (NR) and the south region (SR) were observed in all seasonal tests except spring. This finding relates to a higher abundance of chromophoric dissolved organic matter (CDOM) in the NR due to runoff, especially in the rainy seasons (summer and autumn). CDOM and its terrigenous component had an important impact on Zeu in summer, with the highest precipitation, and impacts from suspended solids and non-algal particles were also found in the NR in summer. The Secchi disk depth in the lake decreased clearly over the years, with significantly negative correlations with the increasing permanganate index and air temperature, implying that organic contaminants (CDOM and/or phytoplankton) are important regulators of water transparency. We estimate that the combined effects of climate warming and changes in land use and land cover are also indirect regulating factors. These findings should be considered in the protection of Lake Fuxian, owing to the importance of light penetration in aquatic ecosystems.

A flagellin-adjuvanted PED subunit vaccine improved protective efficiency against PEDV variant challenge in pigs.

PEDV variants, causing severe diarrhea in neonatal suckling piglets with a mortality rate up to 100%, have being epidemic since late 2010 in china. To meet the pressing need of safe and cost-efficient PED maternal vaccines against PEDV variant, we vaccinated growing piglets with a flagellin-adjuvanted PED vaccine rSF-COE-3D by injection at Houhai acupoint. The vaccination not only enhanced the antibody responses of serum IgG/IgA, mucosal IgA and serum neutralizing antibody, but also improved the production of IFN-γ and IL-4. Moreover, rSF-COE-3D could provide a better protection against the challenge of a high pathogenic PEDV variant, with less diarrhea pigs, less pigs with detectable PEDV shed, lower rank values of feces and less apparent lesions and inflammation in duodenum of the PEDV infected pigs. The improved protective efficiency of rSF-COE-3D compared with COE was mostly benefited from the enhanced production of serum IgA, mucosal IgA in feces and serum neutralizing antibody titers. Taken together, our data suggest that rSF-COE-3D would be a novel efficient PED vaccine.

PED subunit vaccine based on COE domain replacement of flagellin domain D3 improved specific humoral and mucosal immunity in mice.

Porcine epidemic diarrhea (PED) is an important re-emergent infectious disease and inflicts huge economic losses to the swine industry worldwide. To meet the pressing need of developing a safe and cost-efficient PED maternal vaccine, we generated three PED subunit vaccine candidates, using recombined Salmonella flagellin (rSF) as a mucosal molecular adjuvant. Domain D3 in rSF was replaced with COE domain of PEDV to generate rSF-COE-3D. COE fused to the flanking C'/N' terminal of rSF yielded rSF-COE-C and rSF-COE-N. As a result, rSF-COE-3D could significantly improve COE specific antibody production including serum IgG, serum IgA, mucosal IgA and PEDV neutralizing antibody. Furthermore, rSF-COE-3D elicited more CD3+CD8+ T cell and cytokine production of IFN-γ and IL-4 in mouse splenocytes. In summary, our data showed that rSF-COE-3D could improve specific humoral and mucosal immunity in mice, thus suggesting that rSF-COE-3D could be applied as a novel efficient maternal PED vaccine.

Combining hydrogen peroxide addition with sunlight regulation to control algal blooms.

The concentration, light conditions during treatment, and the number of hydrogen peroxide (H2O2) additions as well as the H2O2 treatment combined with subsequent shading to control algal blooms were studied in the field (Lake Dianchi, China). The cyanobacterial stress and injury due to H2O2 were dose dependent, and the control effectiveness and degradation of H2O2 were better and faster under full light than under shading. However, H2O2 was only able to control a bloom for a short time, so it may have promoted the recovery of algae and allowed the biomass to rebound due to the growth of eukaryotic algae. A second addition of H2O2 at the same dose had no obvious effect on algal control in the short term, suggesting that a higher concentration or a delayed addition should be considered, but these alternative strategies are not recommended so that the integrity of the aquatic ecosystem is maintained and algal growth is not promoted. Moreover, shading (85%) after H2O2 addition significantly reduced the algal biomass during the enclosure test, no restoration was observed for nearly a month, and the proportion of eukaryotic algae declined. It can be inferred that algal blooms can be controlled by applying a high degree of shading after treatment with H2O2.

Multi-Year Assessment of Toxic Genotypes and Microcystin Concentration in Northern Lake Taihu, China.

Lake Taihu is the third-largest freshwater lake in China and has been suffering from cyanobacterial blooms for over two decades. The northern part of the lake, Meiliang Bay, is known to be at high risk of dense and sustained Microcystis blooms and toxins. This study aimed to investigate and record the annual and seasonal dynamics of toxic genotype, Microcystis morphospecies succession and microcystin variation. It also aimed to find out the underlying driving factors influencing the dynamic changes. Microcystin (MC) and the Microcystis genotype were quantified using HPLC and quantitative real-time PCR, respectively. Our study, over three consecutive years, showed that the pattern of morphospecies succession was seasonally distinct and annually consistent. During the same period in 2012, 2013 and 2014, the average MC were, on dry weight basis, 733 µg·g(-1), 844 µg·g(-1), 870 µg·g(-1), respectively. The proportion of toxic Microcystis accounted for 41%, 44% and 52%, respectively. Cell bound microcystin was found to correlate with the percentage of toxic Microcystis. Based on historical and current data, we conclude that annual bloom toxicity was relatively stable or possibly increased over the last decade.