The Feasibility of Immobilization of Bioflocculant-producing Bacteria Using Mycelial Pellets as Biomass Carriers

Bioflocculant-producing bacteria Agrobacterium tumefaciens F2 and Bacillus sphaeicus F6 were immobilized onto mycelial pellets to investigate the bioflocculant-producing potential of this combined organism and the corresponding flocculating efficiency. The atomic force microscope ( AFM) images of mycelial surface indicate that the mycelia pellet can immobilize bioflocculant-producing bacteria F2 and F6 as a biomass carrier. The flocculating efficiency of bioflocculant produced by this combined organism was studied under the optimum flocculating conditions obtained by Response Surface Methodology ( RSM ) . The fermentation yield of the combined mycelial pellet is about 2. 6 g / L,which is higher than that of the free bacteria ( only 2. 2 g / L) . Flocculating efficiency of the combined mycelial pellet was comparable with that of bioflocculant generated by the free bacteria. The bioflocculant yield is enhanced and the flocculating efficiency of the co-culture is uninfluenced after immobilized with mycelial pellet as a carrier. In conclusion,the mycelial pellet is feasible as a biomass carrier for the immobilization of bioflocculant-producing bacteria.

基于信息寻求风格术前健康教育对经皮冠状动脉介入治疗患者焦虑和抑郁影响的研究

目的 旨在探讨基于信息寻求风格的术前教育方式在降低经皮冠状动脉介入治疗患者术前焦虑和抑郁的效果.方法 本研究为单盲随机对照试验.2020年4-9月,从中国西南部昆明市1所三级医院的心内科选取114例经皮冠状动脉介入治疗患者,并随机分配到干预组(n=57)和对照组(n=57).所有患者均获得口头的术前健康教育和纸质版的术前健康教育手册,并在干预前采用中文版米勒应对风格量表监测维度子量表(the Chinese Version of the Monitoring Subscale of the Miller Behavioral Style Scale,C-MMBSS)将患者分为"监测型"和"非敏感型".干预组实施基于信息寻求风格的术前健康教育,对照组实施常规术前健康教育.采用状态-特质焦虑量表(State-Trait Anxiety Inventory,STAI)和抑郁自评量表(Self-rating Depression Scale,SDS)在患者入院时和术前1 h时测量其焦虑和抑郁水平,并在出院时测量术前健康教育满意度和住院时间.结果 共有104例患者完成研究(干预组和对照组各52例).基于信息寻求风格的术前健康教育方式在缓解患者术前焦虑(21.5±2.1比23.1±3.1)、抑郁(21.9±2.1比23.1±2.5)和提高术前健康教育满意度(94.4±6.8比85.2±9.8)方面的效果优于常规术前健康教育(P<0.01).干预组和对照组患者住院时长比较[(8.2±3.2)d比(7.8±3.3)d],差异无统计学意义(P>0.05).对照组患者在常规术前健康教育后术前焦虑水平稍有提高(22.6±3.2比23.1±3.1,P<0.05).结论 研究结果显示,基于信息寻求风格的术前健康教育方式可以降低患者术前焦虑、抑郁水平,提高术前健康教育满意度.

Renal blood perfusion in GK rats using targeted contrast enhanced ultrasonography

Objective: To explore application of targeted contrast enhanced ultrasonography in diagnosis of early stage vascular endothelial injury and diabetic nephropathy. Methods: Targeted Sono VueTM microbubble was prepared by attaching anti-TM monoclonal antibody to the surface of ordinary micro-bubble Sono Vue by biotin-avidin bridge method and ultrasonic instrument was used to evaluate the developing situation of targeted microbubble in vitro. Twenty 12-week-old male GK rats and 20 Wistar rats were enrolled in this study, and were randomly divided into targeted angiography group and ordinary angiography group. Targeted microbubbles Sono VueTM or general microbubble Sono Vue were rapidly injected to the rats via tail vein; the developing situation of the two contrast agents in rats kidneys was dynamically observed. Time intensity curve was used to analyse rat kidney perfusion characteristics in different groups. Results: Targeted ultrasound microbubble Sono Vue-TM was successfully constructed, and it could be used to develop an external image. Targeted microbubbles Sono Vue-TM enabled clear development of experimental rat kidney. Time intensity curve shapes of rat kidney of the two groups showed as single apex with steep ascending and slowly descending branch. Compared with the control group, the rising slope of the GK rat renal cortex, medulla in targeted angiography group increased(P<0.05); the peak intensity of medulla increased(P<0.05), and the total area under the curve of medulla increased(P<0.05). Compared with control group, the ascending branch of the GK rat in renal cortex, medulla in ordinary angiography group increased(P<0.05). The peak intensity of the curve increased(P<0.05), and the total area under the curve increased(P<0.05). Compared with the ordinary angiography group, the peak of GK rat medullacurve in targeted angiography group intensity increased(P<0.05), and the total area under the curve increased(P<0.05). Conclusions: Targeted microbubbles Sono VueTM can make a clear development of experimental rat kidney, its stable performance meet the requirement of ultrasonic observation time limit, and it can reflect early changes of blood perfusion in GK rat kindey.

Characterization of Aquabacterium parvum sp. Strain B6 during Nitrate-Dependent Fe(Ⅱ) Oxidation Batch Cultivation with Various Impact Factors

In order to assess the capacity of Aquabacterium parvum sp. strain B6 for nitrate-dependent Fe(Ⅱ) oxidation,batch cultivation was conducted, and its ability to oxidize Fe(Ⅱ) coupled to nitrate reduction in the presence of diverse organic substrates was studied. Meanwhile, the nitrate-removal rate of B6 with various impact factors was further optimized by the response surface methodology(RSM). The results show that strain B6 is capable of utilizing different organic compounds as substrates for nitrate reduction. Compared with yeast extract, B6 showed a greater potential of chemical oxygen demand(COD)degradation and cell proliferation with acetate and glucose mediums, respectively, while citrate was not beneficial for this process due to its low consumption rate. RSM analysis demonstrated that the maximum nitrate-reduction rate of 30.64% could be achieved with an initial pH of 7.4,incubation temperature of 25.0 °C, and carbon source concentration of 266.10 mg/L.

Flocculating Properties and Production of the Compound Bioflocculant by Rhizobium Radiobacter F2 and Bacillus Sphaeicus F6

A compound bioflocculant CBF,produced by mixed culture of Rhizobium radiobacter F2 and Bacillus sphaeicus F6, was investigated with regard to its production and flocculating properties. The optimization of the culture medium constituents including carbon source,nitrogen source and C / N ratio,metal ions and ionic strength on CBF production were studied. Flocculating properties of CBF were examined by a series of experiments and CBF had good flocculating activities in kaolin suspension with divalent cations and stable over wide range of p H. Studies of the flocculating properties revealed that the flocculation could be stimulated by cations Ca2+,Mg2+,Fe2+,Al3+and Fe3+. In addition,it was stable at 4-30 ℃ in the presence of Ca Cl2. It was found to be effective for flocculation of a kaolin suspension under neutral and weak alkaline conditions( p H 7. 0- 9. 0),and flocculating activities of higher than 95% were obtained when the CBF concentrations among 6- 14 mg / L at p H 8. 0. The results of this study indicate that CBF is a potential replacement of conventional synthetic flocculants and is widely applied in water treatment and downstream processing of food and fermentation industries.

Coarse woody debris features of a warm temperate deciduous broad-leaved forest,northern China

Stocking and structural composition of a deciduous broad-leaved forest were determined to predict coarse woody debris quantity by quantifying the empirical relationships between these two attributes.The most ecologically significant families by stem density were Salicaceae,Betulaceae,Fagaceae,and Aceraceae.P opulus davidiana was the most dominant species followed by B etula dahurica,Quercus mongolica,and Acer mono.The four species accounted for 69.5%of total stems.Numerous small-diameter species characterized the coarse woody debris showing a reversed J-shaped distribution.The coarse debris of P.davidiana,B.dahurica,and Q.mongolica mainly comprised the 10–20 cm size class,whereas A.mono debris was mainly in the 5–10 cm size class.The spatial patterns of different size classes of coarse woody debris were analyzed using the g-function to determine the size of the tree at its death.The results indicate that the spatial patterns at the 0–50 m scale shifted gradually from an aggregated to a random pattern.For some species,the larger coarse debris might change from an aggregated to a random distribution more easily.Given the importance of coarse woody debris in forest ecosystems,its composition and patterns can improve understanding of community structure and dynamics.The aggregation pattern might be due to density dependence and self-thinning effects,as well as by succession and mortality.The four dominant species across the different size classes showed distinct aggregated distribution features at different spatial scales.This suggests a correlation between the dominant species population,size class,and aggregated distribution of coarse woody debris.

Effect of C/N Ratio,Temperature,pH on Autotrophic Denitrification Rate with Hydrogen Gas,Iron(Ⅱ) and Sodium Sulfide as Electron Donors

Nitrate is considered to be one of the most widely present pollutants leading to eutrophication of environment. The purpose of this work was to isolate and identify new anaerobic denitrifying bacteria from reservoir sediments and utilize different electron donors for isolates to improve nitrate removal efficiency. Using traditional enrichment approach,one purified anaerobic bacterium( Y12) capable of NO-3-N removal from sediments was obtained. The species identity of Y12 was determined via 16 S rRNA gene sequence analysis to be Acinetobacter. In this work,the fastest denitrification rates were observed with ferrous iron as electron donor.And,slightly slower rates were observed with hydrogen and sodium sulfide as electron donors. However,when used hydrogen gas, ferrous iron and sodium sulfide as electron donors, C / N ratios had little effect on autotrophic denitrification rate at the initial C / N ratio from 1.5 to 9.0. Meanwhile,when made use of hydrogen gas,ferrous iron and sodium sulfide as electron donors,a maximum nitrate removal ratio of 100.00%,91.43%and 87.99% at the temperature of 30 ℃,respectively. Moreover,maximum denitrification activity was observed at p H 6.0-7.0.

Distributed Simulation of Non-Point Source Pollution in Ashi River Basin

In order to get a thorough understanding of non-point source pollution,it is essential to examine its temporal and spatial distribution. A physically-based distributed model,Soil and Water Assessment Tool( SWAT),was used in this research,to quantitatively estimate the NPS load and analyze the temporal and spatial distributions of NPS pollution in Ashi River Basin. The results indicated that SWAT was suitable to simulate stream-flow and water quality in Ashi River Basin. Total Nitrogen which was contributed by NPS( NPS-TN) accounted for 32. 47%-62. 61%,and Total Phosphorus which was contributed by NPS( NPS-TP)accounted for 22. 30%- 57. 85% of the total load respectively. In inter-annual timescale,both NPS-TN and NPS-TP were influenced by stream-flow and fertilizer. However,when compared with fertilizer,NPS pollution was more directly affected by stream-flow. In annual timescale,NPS-TN and NPS-TP mainly occurred in flood season( from May to September). In the aspect of space,spatial differences of NPS-TN and NPS-TP were extremely significant. The spatial variations of NPS pollution were mainly influenced by land use,precipitation,soil and slope.

The TLR7 agonists imiquimod and gardiquimod improve DC-based immunotherapy for melanoma in mice

Toll-like receptors(TLRs)are a family of highly conserved germline-encoded pattern-recognition receptors that are essential for host immune responses.TLR ligands represent a promising class of immunotherapeutics or vaccine adjuvants with the potential to generate an effective antitumor immune response.The TLR7/8 agonists have aroused interest because they not only activate antigen-presenting cells but also promote activation of T and natural killer(NK)cells.However,the exact mechanism by which stimulation of these TLRs promotes immune responses remains unclear,and different TLR7/8 agonists have been found to induce different responses.In this study,we demonstrate that both gardiquimod and imiquimod promote the proliferation of murine splenocytes,stimulate the activation of splenic T,NK and natural killer T(NKT)cells,increase the cytolytic activity of splenocytes against B16 and MCA-38 tumor cell lines,and enhance the expression of costimulatory molecules and IL-12 by macrophages and bone marrow-derived dendritic cells(DCs).In a murine model,both agonists improved the antitumor effects of tumor lysate-loaded DCs,resulting in delayed growth of subcutaneous B16 melanoma tumors and suppression of pulmonary metastasis.Further,we found that gardiquimod demonstrated more potent antitumor activity than imiquimod.These results suggest that TLR7/8 agonists may serve as potent innate and adaptive immune response modifiers in tumor therapy.More importantly,they can be used as vaccine adjuvants to potentiate the efficiency of DC-based tumor immunotherapy.

Can arbuscular mycorrhiza and fertilizer management reduce phosphorus runoff from paddy fields?

Our study sought to assess how much phosphorus（P） runoff from paddy fields could be cut down by fertilizer management and inoculation with arbuscular mycorrhizal fungi. A field experiment was conducted in Lalin River basin, in the northeast China： six nitrogen-phosphorus-potassium fertilizer levels were provided（0, 20%, 40%, 60%, 80%, and 100% of the recommended fertilizer supply）, with or without inoculation with Glomus mosseae. The volume and concentrations of particle P（PP） and dissolved P（DP） were measured for each runoff during the rice growing season. It was found that the seasonal P runoff, including DP and PP, under the local fertilization was 3.7 kg/ha, with PP, rather than DP, being the main form of P in runoff water. Additionally, the seasonal P runoff dropped only by 8.9% when fertilization decreased by 20%; rice yields decreased with declining fertilization. We also found that inoculation increased rice yields and decreased P runoff at each fertilizer level and these effects were lower under higher fertilization. Conclusively, while rice yields were guaranteed arbuscular mycorrhizal inoculation and fertilizer management would play a key role in reducing P runoff from paddy fields.

Characterization and biodegradation kinetics of a new cold-adapted carbamazepine-degrading bacterium, Pseudomonas sp. CBZ-4

Carbamazepine is frequently detected in waters and hardly eliminated during conventional wastewater treatment processes due to its complicated chemical structure and resistance to biodegradation. A carbamazepine-degrading bacterium named CBZ-4 was isolated at a low temperature （10℃） from activated sludge in a municipal wastewater treatment plant. Strain CBZ-4, which can use carbamazepine as its sole source of carbon and energy, was identified as Pseudomonas sp. by the 16S rRNA gene sequence. The composition and percentage of fatty acids, which can reveal the cold-adaptation mechanism of strain CBZ-4, were determined. Strain CBZ-4 can effectively degrade carbamazepine at optimal conditions： pH 7.0, 10℃, 150 r/min rotation speed, and 13% inoculation volume. The average removal rate of carbamazepine was 46.6% after 144 hr of incubation. The biodegradation kinetics of carbamazepine by CBZ-4 was fitted via the Monod model. Vmax and Ks were found to be 0.0094 hr^-1 and 32.5 mg/L, respectively.

Magnetic iron oxide nanoparticles accelerate osteogenic differentiation of mesenchymal stem cells via modulation of long noncoding RNA INZEB2

Nanomaterials are increasingly used for biomedical applications; thus, it is important to understand their biological effects. Previous studies suggested that magnetic iron oxide nanoparticles （IONPs） have tissue-repairing effects. In the present study, we explored cellular effects of IONPs in mesenchymal stem cells （MSCs） and identified the underlying molecular mechanisms. The results showed that our as-prepared IONPs were structurally stable in MSCs and promoted osteogenic differentiation of MSCs as whole particles. Moreover, at the molecular level, we compared the gene expression of MSCs with or without IONP exposure and showed that IONPs upregulated long noncoding RNA INZEB2, which is indispensable for maintaining osteogenesis by MSCs. Furthermore, overexpression of INZEB2 downregulated ZEB2, a factor necessary to repress BMP/Smad- dependent osteogenic transcription. We also demonstrated that the essential role of INZEB2 in osteogenic differentiation was ZEB2-dependent. In summary, we elucidated the molecular basis of IONPs＇ effects on MSCs; these findings may serve as a meaningful theoretical foundation for applications of stem cells to regenerative medicine.

Biosynthesis of gold nanoparticles by Trichoderma sp.WL-Go for azo dyes decolorization

Developing an eco-friendly approach for metallic nanoparticles synthesis is important in current nanotechnology research. In this study, green synthesis of gold nanoparticles （AuNPs） was carried out by a newly isolated strain Trichoderrna sp. WL-Go. UV-vis spectra of AuNPs showed a surface plasmon resonance peak at 550 nm, and transmission electron microscopy images revealed that the AuNPs were of varied shape with well dispersibility. The optimal conditions for AuNPs synthesis were HAuC14 1.0 mmol/L, biomass 0.5 g and pH 7-11. Moreover, the bio-AuNPs could efficiently catalyze the decolorization of various azo dyes. This research provided a new microbial resource candidate for green synthesis of AuNPs and demonstrated the potential application ofbio-AuNPs for azo dye decolorization.

Using a Gaussian mathematical model to define eruptive stages of young volcanic rocks in Tengchong based on laser 40Ar/39Ar dating

Reconstruction of Quaternary environments,late Cenozoic geodynamics and evaluation of volcanic hazards,all depend on the precise delineation of eruptive stages.In recent years,laser 40Ar/39Ar dating methods have been widely used for dating young volcanic rocks,given their stable automated testing process,very low background level and high sensitivity,which meet the requirements for precise dating of young samples.This paper applied high-precision laser 40Ar/39Ar dating to the main volcanic units in the Tengchong area and obtained ages in the range of 0.025–5.1 Ma using conventional data processing methods.However,conventional dating highlighted issues related to very low radiogenic 40Ar content,accidental errors and poor data stability,which led to huge age deviations.Moreover,lacking a unified timescale,conventional methods were unable to strictly define the stages of the Tengchong volcanic eruptions,leading to ongoing controversy.In this study,we applied a Gaussian mathematical model to deal with all 378 original ages from 13 samples.An apparent age-probability diagram,consisting of three independent waveforms,have been obtained.The corresponding isochron ages of these three waveforms suggest there were three volcanic eruptive stages,namely during the Pliocene(3.78±0.04 Ma),early Middle Pleistocene(0.63±0.03 Ma)and late Middle Pleistocene to early Late Pleistocene(0.139±0.005 Ma).These results accurately define eruptive stages in the Tengchong area.

超积累植物与丛枝菌根真菌共生及其联合吸收积累重金属的效应

利用超积累植物进行重金属污染土壤修复是应对全球大面积分布无机污染问题的重要解决方法之一。超积累植物虽然具有超量积累重金属的能力,但其定植、生长和提取功能的发挥都受到重金属胁迫的显著影响。利用丛枝菌根真菌(Arbuscular mycorrhizal fungi,AMF)强化超积累植物功能可联合发挥二者的功能优势,提升修复效率、缩短修复周期、保持修复效果的稳定性和长期性,在日益复杂、严峻的重金属污染治理领域具有重要的研究价值和广阔的应用前景。文中首先给出了超积累植物的概念、中国本土首次报道的典型重金属元素超积累植物和能与AMF形成共生体系的超积累植物名录,系统深入地探讨了AMF对超积累植物生长和吸收累积重金属的影响,以及超积累植物+AMF联合吸收积累重金属的效应与作用机制,认为AMF可通过调节根围理化与生物条件、元素平衡状况、生理代谢和基因表达等途径,增强超积累植物吸收积累重金属的效应,超积累植物+AMF构建的共生体系具备联合修复重金属污染生境的潜力。最后指出了超积累植物+AMF共生联合修复技术当前面临的关键问题、发展方向和应用前景。

Is resource allocation and grain yield of rice altered by inoculation with arbuscular mycorrhizal fungi?

Aims our study quantified the combined effects of fertilization and inoculation with arbuscular mycorrhizal fungi(AMF)on grain yield and allocation of biomass and nutrients in field-grown rice(Oryza sativa l.).Methods a two-factor experiment was conducted at a field site in northeast of China(in shuangcheng,Heilongjiang Province,songhua river basin):six nitrogen-phosphorus-potassium fertilizer levels were provided(0,20,40,60,80 and 100%of the local norm of ferti-lizer supply),with or without inoculation with Glomus mosseae.at maturity,we quantified the percentage of root length colonization by AMF,grain yield,shoot:root ratios,shoot N and P contents and nutrients allocated to panicles,leaves and stems.Important Findingsas expected,inoculation resulted in greatly increased AMF colo-nization,which in turn led to higher shoot:root ratios and greater shoot N contents.shoot:root ratios of inoculated rice increased with increasing fertilization while there was a significant interaction between fertilization and inoculation on shoot:root ratio.additionally,a F inoculation increased panicle:shoot ratios,panicle N:shoot N ratios and panicle P:shoot P ratios,especially in plants grown at low fertilizer levels.Importantly,inoculated rice exhibited higher grain yield,with the maximum improvement(near 62%)at the lower fertilizer end.our results showed that(i)AMFinoculated plants conform to the functional equilibrium theory,albeit to a reduced extent compared to non-inoculated plants and(ii)AMF inoculation resulted in greater allocation of shoot biomass to panicles and increased grain yield by stimulating N and P redis-tribution to panicles.

Reducing nitrogen runoff from paddy fields with arbuscular mycorrhizal fungi under different fertilizer regimes

Nitrogen（N） runoff from paddy fields serves as one of the main sources of water pollution. Our aim was to reduce N runoff from paddy fields by fertilizer management and inoculation with arbuscular mycorrhizal fungi（AMF）. In northeast China, Shuangcheng city in Heilongjiang province, a field experiment was conducted, using rice provided with 0%, 20%, 40%, 60%, 80%,and 100% of the local norm of fertilization（including N, phosphorus and potassium）, with or without inoculation with Glomus mosseae. The volume, concentrations of total N（TN）,dissolved N（DN） and particulate N（PN） of runoff water were measured. We found that the local norm of fertilization led to 18.9 kg/ha of N runoff during rice growing season, with DN accounting for 60%–70%. We also found that reduction in fertilization by 20% cut down TN runoff by 8.2% while AMF inoculation decreased N runoff at each fertilizer level and this effect was inhibited by high fertilization. The combination of inoculation with AMF and 80% of the local norm of fertilization was observed to reduce N runoff by 27.2%. Conclusively, we suggested that the contribution of AMF inoculation combined with decreasing fertilization should get more attention to slow down water eutrophication by reducing N runoff from paddy fields.

Improvement of nitrification efficiency by bioaugmentation in sequencing batch reactors at low temperature

Bioaugmentation 是在在低温度定序批反应堆(SBR ) 与高氨集中对待市政的废水的一个有效方法(10 ?????????????? 楢慯杵敭瑮瑡潩吗？？

Pseudomonas sp.ZXY-1,a newly isolated and highly efficient atrazine-degrading bacterium,and optimization of biodegradation using response surface methodology

Atrazine, a widely used herbicide, is increasing the agricultural production effectively, while also causing great environmental concern. Efficient atrazine-degrading bacterium is necessary to removal atrazine rapidly to keep a safe environment. In the present study, a new atrazine-degrading strain ZXY-1, identified as Pseudomonas, was isolated. This new isolated strain has a strong ability to biodegrade atrazine with a high efficiency of 9.09 mg/L/hr.Temperature, p H, inoculum size and initial atrazine concentration were examined to further optimize the degradation of atrazine, and the synthetic effect of these factors were investigated by the response surface methodology. With a high quadratic polynomial mathematical model（R^2= 0.9821） being obtained, the highest biodegradation efficiency of 19.03 mg/L/hr was reached compared to previous reports under the optimal conditions（30.71°C, pH 7.14, 4.23%（V/V） inoculum size and 157.1 mg/L initial atrazine concentration）.Overall, this study provided an efficient bacterium and approach that could be potentially useful for the bioremediation of wastewater containing atrazine.