Synergistic effects of the entomopathogenic fungus Isaria javanica and low doses of dinotefuran on the efficient control of the rice pest Sogatella furcifera

The rice planthopper,Sogatella furcifera,is a piercing-sucking insect pest of rice,Oryza sativa.It is responsible for significant crop yield losses,and has developed moderate to high resistance to several commonly used chemical insecticides.We investigated the effects of the insect fungal pathogen Isaria javanica,alone and in combination with the chemical insecticide dinotefuran,on S.furcifera under both laboratory and field conditions.Our results show that I.javanica displays high infection efficiency and mortality for different stages of S.furcifera,reducing adult survival,female oviposition and ovary development.Laboratory bioassays showed that the combined use of I.javanica with a low dose(4-16 mg L^(-1))of dinotefuran resulted in higher mortality in S.furcifera than the use of I.javanica or dinotefuran alone.The combined treatment also had more significant effects on several host enzymes,including superoxide dismutase,catalase,peroxidase,and prophenol oxidase activities.In field trials,I.javanica effectively suppressed populations of rice planthoppers to low levels(22-64%of the level in untreated plots).Additional field experiments showed synergistic effects,i.e.,enhanced efficiency,for the control of S.furcifera populations using the combination of a low dose of I.javanica(1×10^(4) conidia mL^(-1))and a low dose of dinotefuran(~4.8-19.2%of normal field use levels),with control effects of>90%and a population level under 50 insects per 100 hills at 3-14 days post-treatment.Our findings indicate that the entomogenous fungus I.javanica offers an attractive biological control addition as part of the integrated pest management(IPM)practices for the control of rice plant pests.

Overcoming the Limits of Cross-Sensitivity:Pattern Recognition Methods for Chemiresistive Gas Sensor Array

As information acquisition terminals for artificial olfaction,chemiresistive gas sensors are often troubled by their cross-sensitivity,and reducing their cross-response to ambient gases has always been a difficult and important point in the gas sensing area.Pattern recognition based on sensor array is the most conspicuous way to overcome the cross-sensitivity of gas sensors.It is crucial to choose an appropriate pattern recognition method for enhancing data analysis,reducing errors and improving system reliability,obtaining better classification or gas concentration prediction results.In this review,we analyze the sensing mechanism of crosssensitivity for chemiresistive gas sensors.We further examine the types,working principles,characteristics,and applicable gas detection range of pattern recognition algorithms utilized in gas-sensing arrays.Additionally,we report,summarize,and evaluate the outstanding and novel advancements in pattern recognition methods for gas identification.At the same time,this work showcases the recent advancements in utilizing these methods for gas identification,particularly within three crucial domains:ensuring food safety,monitoring the environment,and aiding in medical diagnosis.In conclusion,this study anticipates future research prospects by considering the existing landscape and challenges.It is hoped that this work will make a positive contribution towards mitigating cross-sensitivity in gas-sensitive devices and offer valuable insights for algorithm selection in gas recognition applications.

Advanced 3D ordered electrodes for PEMFC applications: From structural features and fabrication methods to the controllable design of catalyst layers

The catalyst layers(CLs) electrode is the key component of the membrane electrode assembly(MEA) in proton exchange membrane fuel cells(PEMFCs). Conventional electrodes for PEMFCs are composed of carbon-supported, ionomer, and Pt nanoparticles, all immersed together and sprayed with a micron-level thickness of CLs. They have a performance trade-off where increasing the Pt loading leads to higher performance of abundant triple-phase boundary areas but increases the electrode cost. Major challenges must be overcome before realizing its wide commercialization. Literature research revealed that it is impossible to achieve performance and durability targets with only high-performance catalysts, so the controllable design of CLs architecture in MEAs for PEMFCs must now be the top priority to meet industry goals. From this perspective, a 3D ordered electrode circumvents this issue with a support-free architecture and ultrathin thickness while reducing noble metal Pt loadings. Herein, we discuss the motivation in-depth and summarize the necessary CLs structural features for designing ultralow Pt loading electrodes. Critical issues that remain in progress for 3D ordered CLs must be studied and characterized. Furthermore, approaches for 3D ordered CLs architecture electrode development, involving material design, structure optimization, preparation technology, and characterization techniques, are summarized and are expected to be next-generation CLs for PEMFCs. Finally, the review concludes with perspectives on possible research directions of CL architecture to address the significant challenges in the future.

Potato tonoplast sugar transporter 1 controls tuber sugar accumulation during postharvest cold storage

Cold-induced sweetening(CIS),the undesirable sugar accumulation in cold-stored potato(Solanum tuberosum L.)tubers,is a severe postharvest issue in the potato processing industry.Although the process of sucrose hydrolysis by vacuolar invertase during potato CIS is well understood,there is limited knowledge about the transportation of sucrose from the cytosol to the vacuole during postharvest cold storage.Here,we report that among the three potato tonoplast sugar transporters(TSTs),StTST1 exhibits the highest expression in tubers during postharvest cold storage.Subcellular localization analysis demonstrates that StTST1 is a tonoplast-localized protein.StTST1 knockdown decreases reducing sugar accumulation in tubers during low-temperature storage.Compared to wild-type,potato chips produced from StTST1-silenced tubers displayed significantly lower acrylamide levels and lighter color after cold storage.Transcriptome analysis manifests that suppression of StTST1 promotes starch synthesis and inhibits starch degradation in cold-stored tubers.We further establish that the increased sucrose content in the StTST1-silenced tubers might cause a decrease in the ABA content,thereby inhibiting the ABA-signaling pathway.We demonstrate that the down-regulation ofβ-amylase StBAM1 in StTST1-silenced tubers might be directly controlled by ABA-responsive element-binding proteins(AREBs).Altogether,we have shown that StTST1 plays a critical role in sugar accumulation and starchmetabolism regulation during postharvest cold storage.Thus,our findings provide a newstrategy to improve the frying quality of cold-stored tubers and reduce the acrylamide content in potato chips.

Comparative histology,transcriptome,and metabolite profi ling unravel the browning mechanisms of calli derived from ginkgo(Ginkgo biloba L.)

Gingko biloba accumulates high levels of secondary metabolites of pharmaceutical value.Ginkgo calli develop a typical browning that reduces its regenerative capacity and thus its usefulness.To elucidate the browning mechanism,histological,transcriptomic,and metabolic alterations were compared between green and browning calli derived from immature ginkgo embryos.Histological observations revealed that browning calli had a more loosely arranged cell structure and accumulated more tannins than in green calli.Integrated metabolic and transcriptomic analyses showed that phenylpropanoid metabolism was specifi-cally activated in the browning calli,and 428 diff erentially expressed genes and 63 diff erentially abundant metabolites,including 12 fl avonoid compounds,were identifi ed in the browning calli compared to the green calli.Moreover,the expression of fl avonol synthase(FLS)and UDP-glucuronosyl-transferase(UGT)genes involved in the fl avonoid pathway was more than tenfold higher in browning calli than in green calli,thus promoting biosynthesis of fl avonol,which serves as a substrate to form glycosylated fl avonoids.Flavonoid glycosides constituted the major coloring component of the browning calli and may act in response to multiple stress conditions to delay cell death caused by browning.Our results revealed the cellular and biochemical changes in browning callus cells that accompanied changes in expression of browning-related genes,providing a scientifi c basis for improving ginkgo tissue culturability.

Demand analysis of an intelligent medication administration system for older adults with chronic diseases based on the Kano model

Objectives Gerontechnology has great potential in promoting older adults’well-being.With the accelerated aging process,gerontechnology has a promising market prospect.However,most technological developers and healthcare professionals attached importance to products’effectiveness,and ignored older adults’demands and user experience,which reduced older adults'adoption intention of gerontechnology use.The inclusion of older adults in the design process of technologies is essential to maximize the effect.This study explored older adults’demands for a self-developed intelligent medication administration system and proposed optimization schemes,thus providing reference to developing geriatric-friendly technologies and products.Methods A cross-sectional survey was conducted to explore older adults’technological demands for the self-developed intelligent medication administration system,and data were analyzed based on the Kano model.A self-made questionnaire was administered from July 2020 to October 2020 after participants used this system for two weeks.The study was registered with the Chinese Clinical Trial Registry(ChiCTR2000040644).Results A total of 354 older adults participated in the survey.Four items,namely larger font size,simpler operation process,scheduled medication reminders and reliable hardware,were classified as must-be attributes;three items,namely searching drug instructions through WeChat,more sensitive system and longer battery life,as attractive attributes;one item,viewing disease-related information through WeChat,as the one-dimensional attribute;and the rest were indifferent attributes,including simple and beautiful displays,blocking advertisements automatically,providing user privacy protection protocol,viewing personal medical information only by logged-in users,recording all the medications,ordering medications through WeChat.The satisfaction values were between 0.24 and 0.69,and dissatisfaction values were between 0.06 and 0.94.Conclusion This study suggested that older adults had personalized technology demands.Including their technological demands and desire may assist in decreasing the digital divide and promoting the satisfaction of e-health and/or m-health.Based on older adults’demands,our study proposed optimization schemes of the intelligent medication administration system,which may help developers design geriatric-friendly intelligent products and nurses to perform older adults-centered and efficient medication management.

Isoflavones’effects on pharmacokinetic profiles of main iridoids from Gardeniae Fructus in rats

Gardeniae Fructus(GF)and Semen Sojae Praeparatum(SSP)are both medicine food homologies and widely used in Chinese clinical prescriptions together.The research investigated the pharmacokinetics of four iridoids in normal rats and isolfavones-fed rats,which were administered with isolfavones from SSP for 7,14,21 and 28 consecutive days.A validated LC-MS/MS method was developed for determining shanzhiside,genipin-1-gentiobioside,geniposide and their metabolite genipin in rat plasma.Plasma samples were pretreated by solid-phase extraction using paeoniflorin as the internal standard.The chromatographic separation was performed on a Waters Atlantis T3(4.6 mm×150 mm,3 mm)column using a gradient mobile phase consisting of acetonitril and water(containing 0.06%acetic acid).The mass detection was under the multiple reaction monitoring(MRM)mode via polarity switching between negative and positive ionization modes.The calibration curves exhibited good linearity(r>0.997)for all components.The lower limit of quantitation was in the range of 1 e10 ng/m L.The intra-day and inter-day precisions(RSD)at three different levels were both less than 12.2%and the accuracies(RE)ranged fromà10.1%to 16.4%.The extraction recovery of them ranged from 53.8%to 99.7%.Pharmacokinetic results indicated the bioavailability of three iridoid glycosides and the metabolite,genipin in normal rats was higher than that in rats exposed to isoflavones.With the longer time of administration of isoflavones,plasma concentrations of iridoids decreased,while genipin sulfate,the phase II metabolite of genposide and genipin-1-gentiobioside,appeared the rising exposure.The pharmacokinetic profiles of main iridoids from GF were altered by isoflavones.

MdWRKY75e enhances resistance to Alternaria alternata in Malus domestica

The Alternaria alternata apple pathotype adversely affects apple(Malus domestica Borkh.)cultivation.However,the molecular mechanisms underlying enhanced resistance to this pathogen in apple remain poorly understood.We have previously reported that MdWRKY75 expression is upregulated by A.alternata infection in‘Sushuai’apples.In this study,we discovered that overexpression of MdWRKY75e increased the resistance of transgenic apple lines to A.alternata infection,whereas silencing this gene enhanced susceptibility to A.alternata infection.Furthermore,we found that MdWRKY75e directly binds to the MdLAC7 promoter to regulate the biosynthesis of laccase and increase the biosynthesis of lignin during A.alternata infection.Moreover,the thickening of the cell wall enhanced the mechanical defense capabilities of apple.In addition,we found that jasmonic acid remarkably induced MdWRKY75e expression,and its levels in transgenic apple lines were elevated.These results indicate that MdWRKY75e confers resistance to the A.alternata apple pathotype mainly via the jasmonic acid pathway and that pathogenesis-related genes and antioxidant-related enzyme activity are involved in the disease resistance of MdWRKY75e transgenic plants.In conclusion,our fi ndings provide insights into the importance of MdWRKY75e for resistance to A.alternata infection in apples.

Structural characterization and comparative analysis of the chloroplast genome of Ginkgo biloba and other gymnosperms

Ginkgo biloba is a famous living“fossil”and has played an important role in the evolution of the Plant Kingdom.Here,the complete chloroplast genome of G.biloba was sequenced and analysed.The chloroplast genome was 156,990 bp long and predicted to encode 134 genes including 85 protein-coding genes,41 tRNA genes and 8 rRNA genes.The chloroplast genome has a typical quadripartite structure with a pair of inverted repeat regions(IRa and IRb,17,732 bp),a large(LSC,99,259 bp)and small single(SSC,22,267 bp)copy region.After an extensive comparison to previously published gymnosperm plastomes,the gene content and organisation of G.biloba showed high divergence,although part was relatively conserved.The two typical IR regions in the G.biloba chloroplast genome were relatively shorter because it the ycf2 gene.In addition,it was obvious that the IR regions and gene loss were responsible for changes in chloroplast genome size and structure stability,which influenced plastome evolution in different gymnosperms.Phylogenetic analysis revealed that G.biloba is sister to cycads rather than to gnetophytes,cupressophytes,and Pinaceae.Overall,the study showed that the genomic characteristics of G.biloba would be of great help in the further research on the taxonomy,species identification and evolutionary history of gymnosperms,especially for their position in plant systematics and evolution.

Group Target Tracking in WSN Based on Convex Hulls Merging

When a mass of individual targets move closely, it is unpractical or unnecessary to localize and track every specific target in wireless sensor networks (WSN). However, they can be tracked as a whole by view of group target. In order to decrease the amount of energy spent on active sensing and communications, a flexible boundary detecting model for group target tracking in WSN is proposed, in which, the number of sensors involved in target tracking is adjustable. Unlike traditional one or multiple individual targets, the group target usually occupies a large area. To obtain global estimated position of group target, a divide-merge algorithm using convex hull is designed. In this algorithm, group target’s boundary is divided into several small pieces, and each one is enclosed by a convex hull which is constructed by a cluster of boundary sensors. Then, the information of these small convex hulls is sent back to a sink. Finally, big convex hull merged from these small ones is considered as the group target’s contour. According to our metric of precision evaluation, the simulation experiments confirm the efficiency and accuracy of this algorithm.

Regeneration and Agrobacterium-mediated genetic transformation of twelve Eucalyptus species

Eucalyptus is a genus of over 900 species and hybrids,and many of them are valuable fast-growing hardwoods.Due to its economic importance,Eucalyptus is one of the early tree species whose genomes were deciphered.However,the lack of efficient genetic transformation systems severely restricts the functional genomic research on the plant.The success of Eucalyptus regeneration and transformation depends greatly on the genotypes and explants.In this study,we systematically screened 26 genotypes from 12 Eucalyptus species in an attempt to obtain Eucalyptus genotypes with high regeneration potential.We developed two common regeneration media that can be applied to most tested Eucalyptus genotypes for both seeding hypocotyls and cloned internodes as explants.We then implemented DsRed2 as a visual marker for genetic transformation efficiency test.Our results suggest that E.camaldulen and E.robusta are amenable for genetic transformation.Finally,we successfully set up a stable Agrobacterium-mediated genetic transformation procedure for both E.camaldulen and E.robusta using seeding hypocotyls and cloned internodes respectively.Taken together,our study provides valuable means for vegetative propagation,gene transformation,CRISPR based gene mutagenesis,activation and suppression,as well as functional characterization of genes in Eucalyptus.

Effects of "Three Controls" Nutrient Management on Population Quality and Yield Components of Rice

[Objectives]This study was conducted to explore the control mechanism of agricultural non-point source pollution,and investigate the feasibility of promoting rice"three controls"nutrient management in Enping City.[Methods]With high-quality conventional rice as a material,such three treatments as three controls fertilization A(ZHY)and B(ZHY)and farmers conventional fertilization method FFP(ZXL)were set up,and the whole process of the late-season plot experiment was recorded.The agronomic characteristics of rice population quality and yield components during rice growth and development under the"three controls"fertilization technology were analyzed.[Results]Compared with the conventional fertilization method,the three controls A(ZHY)fertilization method improved rice yield by 27.13%,seed setting rate by 2.11%and 1 000-grain weight by 3.30%when reducing N,P and K by 27.13%,10.89%and 27.31%,respectively.In the case of three controls B(ZHY)omitting the last fertilization in the three controls fertilization method(4∶2∶3∶1),which saved the formula fertilizer by 11.25%,no difference was caused in yield,but the seed setting rate and 1 000-grain weight were still improved by 3.47%and 2.79%,respectively.Compared with the conventional fertilization method,the top first,second and third basal nodes of the three controls A(ZHY)fertilization method were shortened by 18.82%,17.06%and 20.52%,respectively,which plays an important role in combating typhoon and resisting lodging.[Conclusions]Compared with the conventional fertilization method,rice"three controls"nutrient management can improve yield and lodging resistance of rice,reduce fertilizer loss and agricultural non-point source pollution,and protect ecological environment.

Comparison on Purification Effect of Two Macroalgae Species on Prawn Tailwater

[Objectives]This study was conducted to investigate the purification effects of two common large seaweeds on the tail water of prawn farming in greenhouses,and to determine the best culture density of seaweeds.[Methods]Two large seaweed species,Gracilaria lichevoides and Ulva lactuca,were selected to set four culture densities of 0.5,2,4 g/L and a blank control group,respectively.The seaweeds were cultured in 100 L white polyethylene buckets,each of which contained 50 L of tail water from prawn culture.[Results]After 5 d,the nutrient removal rates of the two seaweeds were directly proportional to the density.There was no significant difference in NH_(4)-N removal rate between G.lichevoides and U.lactuca(P>0.05)by two-way analysis of variance,and the NH_(4)-N removal rate of the latter was higher.The removal rates of NO_(3)-N,TN and TP by G.lichevoides were significantly higher than those by U.lactuca(P<0.05).The specific growth rates of seaweeds were negatively correlated with their culture densities.The specific growth rates of G.lichevoides were 5.73%,1.654%and 0.48%,respectively,and those of U.lactuca were 2.01%,1.187%and 0.138%,respectively,when the culture densities were 0.5,2.0 and 4.0 g/L.Two-factor analysis of variance showed that the former was significantly higher than the latter,when the culture density of the two species of seaweeds was 0.5 g/L(P<0.05).The two-way analysis of variance showed that when the culture density of the two kinds of seaweeds was 0.5 g/L,the specific growth rate of G.lichevoides was significantly higher than that of U.lactuca(P<0.05).Based on the above research,the two macroalgae could reduce the nutrients in the wastewater to a large extent,but the culture density determined the scale and economic benefits of seaweed cultivation and further affected the normal growth,metabolism and quality of the seaweeds.[Conclusions]This study provides some theoretical basis for large-scale seaweed farming and biological selection of in-situ ecological restoration of eutrophic seawater.

Treatment of Shrimp Effluent by Integrated Culture of Bivalves and Macroalgae

[Objectives]To provide a theoretical basis for constructing the best species suitable for local shrimp-bivalves-algae IMTA through the screening of different bivalves and the determination of seaweed density.[Methods]The preliminary studies of different kind of bivalves and macroalgae(Gracilaria lichevoides)used for the purification of shrimp effluent were described.Through the screening of benthic bivalves,the best ratio of integrated culture of bivalves and algae was determined.[Results]Both bivalves and macroalgae had certain purification effects on aquaculture wastewater,but the effects significantly differed from species and breeding density.The removal rate of nutrient declined from Potamocorbula laevis,Sinonovacula constricta,Tegillarca granosa.The mixotrophic culture of 8 ind/L P.laevis and 120 g G.lichevoides had the highest efficiency of purification and removal rates of nutrient:NH4-N:90.67%,TP:86.18%,TN:72.66%,NO3-N:51.85%,respectively.There was a significant difference between the blank control group and the other three groups(P<0.01).The 8 ind/L+120 g group was significantly higher than the 4 ind/L+120 g group(P<0.05)in TP removal rate.Additionally,the difference between four groups was significant in the removal rate of NH4-N and TN(P<0.05),but 2 ind/L+120 g group and 8 ind/L+120 g group in the removal rate of NO3-N had no significant difference(P>0.05).[Conclusions]This research provides a reference for the use of filterable shellfish and large seaweed to treat aquaculture wastewater,and also provides the theoretical basis for constructing the local multi-level breeding structure.

Overexpression of lily LlWRKY22 enhances multiple abiotic stress tolerances in transgenic Arabidopsis

In our previous study,a heat-induced differentially expressed WRKY-IIe gene LlWRKY22 is isolated from lily(Lilium longiflorum),which acts as a positive role in thermotolerance,but whether it is involved in other stress responses is unknown.Here,the expression of LlWRKY22 was indicated to be positively influenced by heat,salt,or mannitol treatments,and its promoter activity was also enhanced after heat,salt,or mannitol treatments.In addition,LlWRKY22 responded to ABA treatment,which activated its expression and also increased the promoter activity.Overexpression of LlWRKY22 in Arabidopsis contributed to growth defects and early flowering.Simultaneously,compared with the wild type,the ABA sensitivity in transgenic lines was increased in both the germination stage and late growth stage.Further analysis showed that LlWRKY22 overexpression elevated the thermotolerance of transgenic plants and induced the expression of AtDREB2A,AtDREB2B,AtDREB2C,and AtJUB1.The salt and mannitol tolerances of the overexpression lines were also improved.Overall,our results illustrated that LlWRKY22 is affected by heat,salt,and osmotic stresses,and positively regulates heat,salt,and osmotic tolerances,which reveals that it acts as a generalist character responding to different abiotic stresses.And further to that,the regulatory pathway of LlWRKY22 also involves in ABA signaling.

Iris:a multi-constraint graphic layout generation system

In graphic design,layout is a result of the interaction between the design elements in the foreground and background images.However,prevalent research focuses on enhancing the quality of layout generation algorithms,overlooking the interaction and controllability that are essential for designers when applying these methods in realworld situations.This paper proposes a user-centered layout design system,Iris,which provides designers with an interactive environment to expedite the workflow,and this environment encompasses the features of user-constraint specification,layout generation,custom editing,and final rendering.To satisfy the multiple constraints specified by designers,we introduce a novel generation model,multi-constraint LayoutVQ-VAE,for advancing layout generation under intra-and inter-domain constraints.Qualitative and quantitative experiments on our proposed model indicate that it outperforms or is comparable to prevalent state-of-the-art models in multiple aspects.User studies on Iris further demonstrate that the system significantly enhances design efficiency while achieving human-like layout designs.

UI layers merger: merging UI layers via visual learning and boundary prior

With the fast-growing graphical user interface(GUI)development workload in the Internet industry,some work attempted to generate maintainable front-end code from GUI screenshots.It can be more suitable for using user interface(UI)design drafts that contain UI metadata.However,fragmented layers inevitably appear in the UI design drafts,which greatly reduces the quality of the generated code.None of the existing automated GUI techniques detects and merges the fragmented layers to improve the accessibility of generated code.In this paper,we propose UI layers merger(UILM),a vision-based method that can automatically detect and merge fragmented layers into UI components.Our UILM contains the merging area detector(MAD)and a layer merging algorithm.The MAD incorporates the boundary prior knowledge to accurately detect the boundaries of UI components.Then,the layer merging algorithm can search for the associated layers within the components’boundaries and merge them into a whole.We present a dynamic data augmentation approach to boost the performance of MAD.We also construct a large-scale UI dataset for training the MAD and testing the performance of UILM.Experimental results show that the proposed method outperforms the best baseline regarding merging area detection and achieves decent layer merging accuracy.A user study on a real application also confirms the effectiveness of our UILM.

Eu^(3+)-Bi^(3+)Codoping Double Perovskites for Single-Component White-Light-Emitting Diodes

Double perovskites(DPs)with Cs_(2)AgInCl_(6) composition,as one of the lead-free perovskites,have been in the spotlight owing to their intriguing optical properties,namely,self-trapped exciton(STE)emission and dopant-induced photoluminescence.However,the current DPs still face the challenge of low photoluminescence efficiency and cannot be applied in practice.Herein,we synthesize the Bi^(3+)and Eu^(3+)codoped Cs_(2)AgInCl_(6) DPs,which displays enhanced STE and Eu^(3+)ions characteristic emissions.Our results indicate that the Eu^(3+)ions mainly substitute the In sites and can increase the radiative recombination rate and exciton binding energy of STEs,which is discovered that Eu^(3+)ions can promote the localization of STEs by breaking the inversion symmetry of the Cs_(2)AgInCl_(6) lattice.The existence of Bi^(3+)ions decreases the excitation(absorption)energy,provides a new absorption channel,and increases the energy transfer rate to Eu^(3+)ions.Through adjusting the Bi^(3+)and Eu^(3+)concentrations,a maximum photoluminescence quantum yield of 80.1%is obtained in 6%Eu^(3+)and 0.5%Bi^(3+)codoped Cs_(2)AgInCl_(6) DPs.Finally,the high-quality single-component white-light-emitting diodes based on Bi^(3+)and Eu^(3+)codoped Cs_(2)AgInCl_(6) DPs and a 410-nm commercial ultraviolet chip are fabricated with the optimum color rendering index of 89,the optimal luminous efficiency of 88.1 lm/W,and a half-lifetime of 1,493 h.This work puts forward an effective lanthanide and transition metals codoping strategy to design single-component white-light emitter,taking a big step forward for the application lead-free DPs.

艾比湖湿地芦苇根际土壤氨氧化古菌的多样性和群落结构

[目的]旨在揭示耐盐植物芦苇根际与非根际土壤AOA群落结构间的差异,为深入研究盐生植物根际土壤微生物与耐盐性之间的关系提供理论基础。[方法]应用高通量测序技术以氨单加氧酶基因(amoA)为分子标记,对新疆艾比湖湿地荒漠生态系统不同季节(春、夏、秋)芦苇根际与非根际土壤氨氧化古菌(AOA)的多样性和群落结构进行研究。[结果]结果表明,不同季节芦苇根际土壤AOA多样性和丰富度存在差异,相比非根际土壤,夏季和秋季芦苇根际土壤AOA多样性较低丰富度较高,春季多样性较高丰富度较低。芦苇根际土壤中AOA的多样性为春季>夏季>秋季。AOA群落组成分析表明,土壤样品中AOA群落主要集中在泉古菌门(Crenarchaeota)和奇古菌门(Thaumarchaeota),其中泉古菌门为主要优势菌门。RDA分析表明,含水量(SM)、有机质(SOM)、总氮(TN)和pH是影响芦苇根际土壤AOA群落多样性和丰富度的主要环境因子。[结论]不同季节芦苇根际土壤AOA多样性及丰富度存在差异,相比非根际土壤,芦苇根际土壤AOA更丰富。

不同时期艾比湖湿地盐角草群落土壤固氮微生物的多样性分析

[目的]研究新疆艾比湖湿地不同季节盐角草根际和非根际土壤固氮微生物的多样性和丰富度与环境因子的相关性,以期探究在荒漠化和盐渍化不断严重的艾比湖湿地中随着季节变化的固氮微生物群落对恢复生态功能起到的潜在作用,为后续的湿地保护和退化恢复工作提供理论支持和数据基础。[方法]应用Illumina HiSeq PE250测序技术,分析6个土壤样本固氮微生物的多样性,结合相关的理化因子并利用RDA分析法探究土壤理化性质和固氮微生物菌落结构及丰富度的相关性。[结果]艾比湖湿地盐角草植物根际土壤的固氮微生物多样性高于非根际土壤,7月的土壤固氮微生物多样性高于10月和4月的土壤。土杆菌属(Geobacter)、假单胞菌属(Pseudomonas)、固氮菌属(Azotobacter)和慢生根瘤菌属(Bradyrhizobium)等为盐角草根际和非根际土壤中的共同优势菌属。这些固氮微生物优势菌属隶属于变形菌门(Proteobacteria)和蓝藻门(Cyanobacteria),且相对丰富度占比为85%和10%,其余各菌门共占比较少,仅为5%。土壤中固氮微生物的优势菌群与碱解氮(AN)、全氮(TN)、速效钾(AK)和有效磷(TP)呈显著相关。[结论]随着时间的推移土壤样本中固氮微生物的多样性和群落结构也发了改变,同一时期植物根际与非根际土壤中固氮微生物的群落结构并不相同。土壤的环境因子与固氮细菌的群落结构和丰富度的相关性研究可以为艾比湖湿地的退化恢复提供数据基础和理论支持。