The term‘ornamental plant’refers to all plants with ornamental value,which generally have beautiful flowers or special plant architectures.China is rich in ornamental plant resources and known as the“mother of gard...The term‘ornamental plant’refers to all plants with ornamental value,which generally have beautiful flowers or special plant architectures.China is rich in ornamental plant resources and known as the“mother of gardens”.Genomics is the science of studying genomes and is useful for carrying out research on genome evolution,genomic variations,gene regulation,and important biological mechanisms based on detailed genome sequence information.Due to the diversity of ornamental plants and high sequencing costs,the progress of genome research on ornamental plants has been slow for a long time.With the emergence of new sequencing technologies and a reduction in costs since the whole-genome sequencing of the first ornamental plant(Prunus mume)was completed in 2012,whole-genome sequencing of more than 69 ornamental plants has been completed in<10 years.In this review,whole-genome sequencing and resequencing of ornamental plants will be discussed.We provide analysis with regard to basic data from whole-genome studies of important ornamental plants,the regulation of important ornamental traits,and application prospects.展开更多
Ball milling is an environmentally friendly technology for the remediation of petroleumcontaminated soil(PCS),but the cleanup of organic pollutants requires a long time,and the post-remediation soil needs an economica...Ball milling is an environmentally friendly technology for the remediation of petroleumcontaminated soil(PCS),but the cleanup of organic pollutants requires a long time,and the post-remediation soil needs an economically viable disposal/reuse strategy due to its vast volume.The present paper develops a ball milling process under oxygen atmosphere to enhance PCS remediation and reuse the obtained carbonized soil(BCS-O)as wastewater treatment materials.The total petroleum hydrocarbon removal rates by ball milling under vacuum,air,and oxygen atmospheres are 39.83%,55.21%,and 93.84%,respectively.The Langmuir and pseudo second-order models satisfactorily describe the adsorption capacity and behavior of BCS-O for transition metals.The Cu^(2+),Ni^(2+),and Mn^(2+)adsorbed onto BCS-O were mainly bound to metal carbonates and metal oxides.Furthermore,BCS-O can effectively activate persulfate(PDS)oxidation to degrade aniline,while BCS-O loaded with transition metal(BCS-O-Me)shows better activation efficiency and reusability.BCS-O and BCS-O-Me activated PDS oxidation systems are dominated by^(1)O_(2)oxidation and electron transfer.The main active sites are oxygen-containing functional groups,vacancy defects,and graphitized carbon.The oxygen-containing functional groups and vacancy defects primarily activate PDS to generate^(1)O_(2)and attack aniline.Graphitized carbon promotes aniline degradation by accelerating electron transfer.The paper develops an innovative strategy to simultaneously realize efficient remediation of PCS and sequential reuse of the postremediation soil.展开更多
Over the past decades,the expansion of natu-ral secondary forests has played a crucial role in offsetting the loss of primary forests and combating climate change.Despite this,there is a gap in our understanding of ho...Over the past decades,the expansion of natu-ral secondary forests has played a crucial role in offsetting the loss of primary forests and combating climate change.Despite this,there is a gap in our understanding of how tree species’growth and mortality patterns vary with eleva-tion in these secondary forests.In this study,we analyzed data from two censuses(spanning a five-year interval)conducted in both evergreen broadleaved forests(EBF)and temperate coniferous forests(TCF),which have been recovering for half a century,across elevation gradients in a subtropical mountain region,Mount Wuyi,China.The results indicated that the relative growth rate(RGR)of EBF(0.028±0.001 cm·cm^(-1)·a^(-1))and the mortality rate(MR)(20.03%±1.70%)were 27.3%and 16.4%higher,respec-tively,than those of TCF.Interestingly,the trade-off between RGR and MR in EBF weakened as elevation increased,a trend not observed in TCF.Conversely,TCF consistently showed a stronger trade-off between RGR and MR compared to EBF.Generalized linear mixed models revealed that ele-vation influences RGR both directly and indirectly through its interactions with slope,crown competition index(CCI),and tree canopy height(CH).However,tree mortality did not show a significant correlation with elevation.Additionally,DBH significantly influenced both tree growth and mortal-ity,whereas and CH and CCI had opposite effects on tree growth between EBF and TCF.Our study underscores the importance of elevation in shaping the population dynamics and the biomass carbon sink balance of mountain forests.These insights enhance our understanding of tree species’life strategies,enabling more accurate predictions of forest dynamics and their response to environmental changes.展开更多
Membrane fouling remains the primary economic barrier to the widespread implementation of membrane bioreactors (MBRs), despite the fact that they lead to the production of high-quality effluent. Operational conditions...Membrane fouling remains the primary economic barrier to the widespread implementation of membrane bioreactors (MBRs), despite the fact that they lead to the production of high-quality effluent. Operational conditions are critical factors influencing membrane fouling. This study aimed to investigate the simultaneous impacts of temperature and hydraulic retention time (HRT) variations on membrane fouling. Experiments were conducted at three different temperatures (18°C, 25°C, and 32°C) and HRTs (6 h, 9 h, and 15 h). The results demonstrated that increases in both temperature and HRT contributed to a reduction in membrane fouling. Additionally, a positive interaction between temperature and HRT was observed in the linear slope variation of membrane permeation, with temperature variations exerting a greater influence on membrane fouling than HRT variations. Fouling factor analysis revealed that increases in temperature and HRT led to decreased concentrations of soluble microbial products (SMP) and extracellular polymeric substances (EPS), particularly carbohydrates, in the activated sludge. Analyses of the cake layer of the membrane indicated that increasing temperature and HRT reduced EPS levels, particularly polysaccharides and proteins;altered primary protein structure;and increased the mean particle size distribution. Ultimately, these changes led to reductions in both reversible and irreversible hydraulic resistances. This study highlights the importance of optimizing operational parameters such as temperature and HRT to enhance membrane performance and treatment efficiency in MBR systems while mitigating fouling.展开更多
A promising structured catalyst was developed through proper coating of boron-modified ZSM-5 using SiO_(2) and Al_(2)O_(3)-containing binders to investigate catalytic performance as well as mechanical stability of the...A promising structured catalyst was developed through proper coating of boron-modified ZSM-5 using SiO_(2) and Al_(2)O_(3)-containing binders to investigate catalytic performance as well as mechanical stability of the catalyst in a monolithic reactor.The reference and boron-modified ZSM-5 catalysts were synthesized by hydrothermal route.The adherence strength of catalyst samples was characterized using ultrasonic vibration method and FESEM analysis.A series of comparative performance tests were also conducted in two reactors,including monolithic and extruded catalysts for the production of propylene from methanol at atmospheric pressure,reaction temperatures of 500℃,and methanol weight hourly space velocity(WHSV)of 1.5 h^(-1).Initial findings demonstrate that applying the B-modified ZSM-5zeolite in a monolith reactor increased propylene selectivity by about 26%compared to the conventional extruded ZSM-5 catalyst.Moreover,silica bonded to the B-ZSM-5 catalyst in the monolithic reactor,owning sufficient adhesion properties;the proposed catalyst showed the best catalytic performance,with not only a high propylene selectivity(58.5%)but also a large propylene/ethylene(P/E)ratio(8.6).The findings attained in this work would be useful in the production of new efficient catalysts based on a zeolite-coated honeycomb monolith in the methanol-to-propylene process.展开更多
Bioleaching was examined for copper extraction from a low grade ore using mesophilic and moderate thermophilic bacteria. Five equal size columns were used for the leaching of the ore. Sulfuric acid solution with a flo...Bioleaching was examined for copper extraction from a low grade ore using mesophilic and moderate thermophilic bacteria. Five equal size columns were used for the leaching of the ore. Sulfuric acid solution with a flow rate of 3.12 L·m-2·h-1 and pH 1.5 passed through each column continuously for 90 d. In the first and the second column, bioleaching was performed without agglomeration of the ore and on the agglomerated ore, respectively. 28wt% of the copper was extracted in the first column after 40 d, while this figure was 38wt% in the second column. After 90 d, however, the overall extractions were almost the same for both of them. Bioleaching with mesophilic bacteria was performed in the third column without agglomeration of the ore and in the fourth column on the agglomerated ore. After 40 d, copper extractions in the third and the fourth columns were 62wt% and 70wt%, respectively. Copper extractions were 75wt% for both the columns after 90 d. For the last column, bioleaching was performed with moderate thermophilic bacteria and agglomerated ore. Copper extractions were 80wt% and 85wt% after 40 and 90 d, respectively. It was concluded that crushing and agglomeration of the ore using bacteria could enhance the copper extraction considerably.展开更多
The pollution of antibiotics commonly existed throughout the entire aquaculture process,but the residues of antibiotics at different aquaculture stages have rarely been studied.This study investigated the occurrence,d...The pollution of antibiotics commonly existed throughout the entire aquaculture process,but the residues of antibiotics at different aquaculture stages have rarely been studied.This study investigated the occurrence,distribution and risk assessment of antibiotics at different aquaculture stages (the non-aquaculture stage,the early aquaculture stage,the middle aquaculture stage,and the late aquaculture stage) in two typical marine aquaculture areas(Mahegang River and Dingzi Bay) surrounding the Yellow Sea.Fluoroquinolones and tetracyclines were commonly used antibiotics in the aquaculture of these areas with high detection frequencies (17%to 83%).Compared among four aquaculture stages,the highest concentration of antibiotics (9032.08 ng/L) in aquaculture ponds was detected at the late aquaculture stage.And the antibiotic pollution level of natural water was directly related to the aquaculture stages.Similarly,at the aquaculture stages,the detection frequency of antibiotics in sediments was higher than that at the non-aquaculture stage.Based on the correlation analysis,the concentration of main antibiotics in water showed a positive correlation with total nitrogen (p<0.05) and chlorophyll a (p<0.01),while it showed a negative correlation with salinity (p<0.01) in coastal water of the Dingzi Bay.According to the risk assessment,with the development of aquaculture stages,the selection pressure of fluoroquinolones and tetracyclines on resistant bacteria had increased.And the ecological risks caused by sulfonamides and tetracyclines to aquatic organisms had also increased markedly.Overall,this study may provide a reference for formulating regulatory policies regarding antibiotic use at different aquaculture stages.展开更多
The distributions of dimethylsulfide (DMS) and its precursor dimethylsulfoniopropionate (DMSP) in surface water of the Yellow Sea and the Bohai Sea were studied during June 2011. The mean concentrations and ranges...The distributions of dimethylsulfide (DMS) and its precursor dimethylsulfoniopropionate (DMSP) in surface water of the Yellow Sea and the Bohai Sea were studied during June 2011. The mean concentrations and ranges of DMS, dissolved DMSP (DMSPd), and particulate DMSP (DMSPp) in surface waters were 6.85 (1.60-12.36), 7.25 (2.28-19.05) and 61.87 (6.28-224.01) nmol/L, respectively. There were strong correlations between DMSPp and chlorophyll a in the Bohai Sea and the North Yellow Sea, respectively, and concentrations of DMS and DMSP were high, with a relatively high proportion of dinoflagellates, in the region of the South Yellow Sea Cold Water Mass. Results show that phytoplankton biomass and species composition were important factors that controlled the distribution of DMS and DMSP. Complex environmental factors, including nutrients, transparency, and terrestrial runoff, might also influence the variability in DMS and DMSP. Biological production and consumption rates of DMS in the Bohai Sea were higher than those in the Yellow Sea. DMS production rates were closely correlated with DMSPd concentrations. DMS and DMSP exhibited obvious diel variations, with high concentrations occurring in the late afternoon (16:00-19:00) and low concentrations occurring during the night, implying that the intensity of solar radiation had a significant influence on these variations. Size distributions of chlorophyll a and DMSPp were also investigated and large nanoplankton (5-20 μm), mainly diatoms, contributed significantly to chlorophyll a and DMSPp at most stations. The average sea-to-air flux of DMS in the study area was estimated to be 11.07 μmol/(m^2·d) during the summer.展开更多
In large-scale deer farming image analysis,K-means or maximum between-class variance(Otsu)algorithms can be used to distinguish the deer from the background.However,in an actual breeding environment,the barbed wire or...In large-scale deer farming image analysis,K-means or maximum between-class variance(Otsu)algorithms can be used to distinguish the deer from the background.However,in an actual breeding environment,the barbed wire or chain-link fencing has a certain isolating effect on the deer which greatly interferes with the identification of the individual deer.Also,when the target and background grey values are similar,the multiple background targets cannot be completely separated.To better identify the posture and behaviour of deer in a deer shed,we used digital image processing to separate the deer from the background.To address the problems mentioned above,this paper proposes an adaptive threshold segmentation algorithm based on color space.First,the original image is pre-processed and optimized.On this basis,the data are enhanced and contrasted.Next,color space is used to extract the several backgrounds through various color channels,then the adaptive space segmentation of the extracted part of the color space is performed.Based on the segmentation effect of the traditional Otsu algorithm,we designed a comparative experiment that divided the four postures of turning,getting up,lying,and standing,and successfully separated multiple target deer from the background.Experimental results show that compared with K-means,Otsu and hue saturation value(HSV)+K-means,this method is better in performance and accuracy for adaptive segmentation of deer in artificial breeding scenes and can be used to separate artificially cultivated deer from their backgrounds.Both the subjective and objective aspects achieved good segmentation results.This article lays a foundation for the effective identification of abnormal behaviour in sika deer.展开更多
Lithium–sulfur(Li-S)batteries have been considered as promising candidates for large-scale high energy density devices due to the potentially high energy density,low cost,and more pronounced ecological compatibility....Lithium–sulfur(Li-S)batteries have been considered as promising candidates for large-scale high energy density devices due to the potentially high energy density,low cost,and more pronounced ecological compatibility.However,the complex Li-S conversion reactions,unsatisfactory battery performance,and unsafe metallic Li anode restrict the development of Li-S batteries to achieve commercialization.This review mainly focuses on three aspects which are the remaining challenges,recent advances,and applications in Li-S batteries.Firstly,this review portrays Li-S conversion chemistry involving the multi-step and multi-electron reaction mechanism,as well as the remaining challenges.Then,the scientific strategies and very recent advances of the cathode,electrolyte,lithium anode,and other constituent parts of Li-S batteries are detailly summed up,as well as their advantages and limitations.For the sake of promoting the Li-S batteries practicalization,next section is primarily concerned with problems,the corresponding solutions,and application scenarios of practical pouch cells.Finally,the important findings as guidelines and some future directions as trends for developing emerging Li-S batteries are briefly summarized.展开更多
The Yaojialing deposit is the first large-scale Zn-Au-Cu polymetallic skarn deposit located in the Shatanjiao ore field of the Tongling area in the Middle-Lower Yangtze belt.It has distinct metallogenic characteristic...The Yaojialing deposit is the first large-scale Zn-Au-Cu polymetallic skarn deposit located in the Shatanjiao ore field of the Tongling area in the Middle-Lower Yangtze belt.It has distinct metallogenic characteristics and is clearly different from the known skarn Cu-Au deposits in the Tongling area and the Middle-Lower Yangtze belt.Previous studies of the Yaojialing deposit have included rock geochemistry,alteration and mineralization characteristics,as well as metallogenesis and metallogenic models.However,there are still numerous problems concerning the coexistence of multiple elements,metallogenetic specialization of the magma and the metallogenic model.In this study,using the latest production exploration work on the deposit,we investigated the Yaojialing deposit including its geological characteristics,petrography,LA-ICP MS zircon U-Pb dating and whole rock geochemistry.Two kinds of magmatic rocks have been distinguished for the first time in the deposit,amongst which the granodiorite porphyry exposed on the surface of the mining area,which is the host rock of the veined lead-zinc ore body,is the wall-rock intrusion;and the deep concealed quartz monzonite porphyry is the causative intrusion,the distribution of orebodies and wall-rock alteration characteristics showing regular zoning around the quartz monzonite porphyry.The^(206)Pb/^(238)U weighted average age of the granodiorite porphyry is 140.2±1.0 Ma(MSWD=0.85,n=13)by LA-ICP MS zircon U-Pb dating,while the quartz monzonite porphyry is 138.9±1.2 Ma(MSWD=0.60,n=16),which is consistent with petrographic evidence.The geochemical characteristics show that the quartz monzonite porphyry is a high-K calc-alkaline series peraluminous rock.The trace element characteristics show that the quartz monzonite porphyry is enriched in LILE such as K,Rb,Sr,Ba and LREE,yet depleted in HFSE such as Nb,Ta,P and Ti.The Yaojialing deposit shows the mineralization characteristics of proximal skarn and distal skarn,having the common characteristics of'multi-storey'and'Trinity'metallogenic models.展开更多
Prunus mume is an important woody plant that has high ornamental and economic value, widely distributed and used in landscape architecture in East Asia. In plants, basic(region) leucine zipper(bZIP) transcription fact...Prunus mume is an important woody plant that has high ornamental and economic value, widely distributed and used in landscape architecture in East Asia. In plants, basic(region) leucine zipper(bZIP) transcription factors play important regulatory roles in growth, development,dormancy and abiotic stress. To date, bZIP transcription factors have not been systematically studied in P. mume. In this study, 49 bZIP genes were first identified in P. mume, and the PmbZIP family was divided into 12 groups according to the grouping principles for the Arabidopsis thaliana bZIP family. For the first time, we constructed a detailed model of the PmbZIP domains(R-x_(3)–N-(x)_7-R/K-x_(2)-K-x_(6)-L-x_(6)-L-_(6)-L). Phylogenetic and synteny analyses showed that PmbZIPs duplication events might have occurred during the large-scale genome duplication events. A relatively short time of speciation and the finding that 91.84% of the bZIP genes formed orthologous pairs between P. mume and Prunus armeniaca provided evidence of a close relationship. Gene expression patterns were analysed in different tissues and periods, indicating that PmbZIP genes with the same motifs exhibited similar expression patterns. The gene expression results showed that PmbZIP31/36/41 genes played a more prominent role in the response to freezing stress than cold stress. The expression level of almost all subset Ⅲ genes was upregulated under freezing treatment, especially after cold exposure. We analysed the gene expression patterns of PmbZIP12/31/36/41/48 and their responses to low-temperature stress, which provided useful resources for future studies on the cold/freezing-tolerant molecular breeding of P. mume.展开更多
Hard carbon is regarded as a promising anode candidate for sodium-ion batteries due to its low cost,relatively low working voltage,and satisfactory specific capacity.However,it still remains a challenge to obtain a hi...Hard carbon is regarded as a promising anode candidate for sodium-ion batteries due to its low cost,relatively low working voltage,and satisfactory specific capacity.However,it still remains a challenge to obtain a high-performance hard carbon anode from cost-effective carbon sources.In addition,the solid electrolyte interphase(SEI)is subjected to continuous rupture during battery cycling,leading to fast capacity decay.Herein,a lignin-based hard carbon with robust SEI is developed to address these issues,effectively killing two birds with one stone.An innovative gas-phase removal-assisted aqueous washing strategy is developed to remove excessive sodium in the precursor to upcycle industrial lignin into high-value hard carbon,which demonstrated an ultrahigh sodium storage capacity of 359 mAh g^(-1).It is found that the residual sodium components from lignin on hard carbon act as active sites that controllably regulate the composition and morphology of SEI and guide homogeneous SEI growth by a near-shore aggregation mechanism to form thin,dense,and organic-rich SEI.Benefiting from these merits,the as-developed SEI shows fast Na+transfer at the interphases and enhanced structural stability,thus preventing SEI rupture and reformation,and ultimately leading to a comprehensive improvement in sodium storage performance.展开更多
A continuous flow bioreactor was operated for 300 days to investigate partial nitritation(PN)of mature landfill leachate,establishing the long-term performance of the system in terms of the microbial community composi...A continuous flow bioreactor was operated for 300 days to investigate partial nitritation(PN)of mature landfill leachate,establishing the long-term performance of the system in terms of the microbial community composition,evolution,and interactions.The stable operation phase(31-300 d)began after a 30 days of start-up period,reaching an average nitrite accumulation ratio(NAR)of 94.43%and a ratio of nitrite nitrogen to ammonia nitrogen(NO_(2)^(−)-N/NH_(4)^(+)-N)of 1.16.Some fulvic-like and humic-like compounds and proteins were effectively degraded in anaerobic and anoxic tanks,which was consistent with the corresponding abundance of methanogens and syntrophic bacteria in the anaerobic tank,and organic matter degrading bacteria in the anoxic tank.The ammonia-oxidizing bacteria(AOB)Nitrosomonas was found to be the key functional bacteria,exhibiting an increase in abundance from 0.27%to 6.38%,due to its collaborative interactions with organic matter degrading bacteria.In-situ inhibition of nitrite-oxidizing bacteria(NOB)was achieved using a combination of free ammonia(FA)and free nitrous acid(FNA),low dissolved oxygen(DO)with fewer bioavailable organics conditions were employed to maintain stable PN and a specific ratio of NO_(2)^(−)-N/NH_(4)^(+)-N,without an adverse impact on AOB.The synergistic relationships between AOB and both denitrifying bacteria and organic matter degrading bacteria,were found to contribute to the enhanced PN performance and microbial community structure stability.These findings provide a theoretical guidance for the effective application of PN-Anammox for mature landfill leachate treatment.展开更多
Crape myrtle(Lagerstroemia indica)is a globally used ornamental woody plant and is the representative species of Lagerstroemia.However,studies on the evolution and genomic breeding of L.indica have been hindered by th...Crape myrtle(Lagerstroemia indica)is a globally used ornamental woody plant and is the representative species of Lagerstroemia.However,studies on the evolution and genomic breeding of L.indica have been hindered by the lack of a reference genome.Here we assembled the first high-quality genome of L.indica using PacBio combined with Hi-C scaffolding to anchor the 329.14-Mb genome assembly into 24 pseudochromosomes.We detected a previously undescribed independent whole-genome triplication event occurring 35.5 million years ago in L.indica following its divergence from Punica granatum.After resequencing 73 accessions of Lagerstroemia,the main parents of modern crape myrtle cultivars were found to be L.indica and L.fauriei.During the process of domestication,genetic diversity tended to decrease in many plants,but this was not observed in L.indica.We constructed a high-density genetic linkage map with an average map distance of 0.33 cM.Furthermore,we integrated the results of quantitative trait locus(QTL)using genetic mapping and bulk segregant analysis(BSA),revealing that the major-effect interval controlling internode length(IL)is located on chr1,which contains CDL15,CRG98,and GID1b1 associated with the phytohormone pathways.Analysis of gene expression of the red,purple,and white flower-colour flavonoid pathways revealed that differential expression of multiple genes determined the flower colour of L.indica,with white flowers having the lowest gene expression.In addition,BSA of purple-and green-leaved individuals of populations of L.indica was performed,and the leaf colour loci were mapped to chr12 and chr17.Within these intervals,we identified MYB35,NCED,and KAS1.Our genome assembly provided a foundation for investigating the evolution,population structure,and differentiation of Myrtaceae species and accelerating the molecular breeding of L.indica.展开更多
Plant architecture includes vital traits that influence and benefit crops,and economically important trees.Different plant architectures provide natural beauty.Weeping ornamental plants are aesthetically appealing to ...Plant architecture includes vital traits that influence and benefit crops,and economically important trees.Different plant architectures provide natural beauty.Weeping ornamental plants are aesthetically appealing to people.The regulatory mechanism controlling the weeping trait is poorly understood in crape myrtle.To investigate the weeping trait mechanism,transcriptional profiling of different organs in weeping and upright crape myrtle was performed based on phenotype.Phenotypic and histological analyses demonstrated that endodermal cells were absent,and that new shoot phenotypes could be rescued by the GA3 treatment of weeping plants.The transcriptional analysis and coexpression network analysis(WGCNA)of differentially expressed genes indicated that GA synthesis and signal transduction pathways play a role in weeping traits.When the expression level of a negative element of GA signaling,LfiGRAS1,was reduced by virus-induced gene silencing(VIGS),new branches grew in infected plants in a negatively geotropic manner.An integrated analysis implied that GA had a strong influence on weeping crape myrtle by interacting with other factors.This study helps to elucidate the mechanism governing the weeping trait and can improve the efficiency of breeding in Lagerstroemia.展开更多
Straw pellets are widely promoted and expected to be a cleaner alternative fuel to unprocessed crop residues and rawcoal in rural China.However,the effectiveness of these dissemination programs is not well evaluated.I...Straw pellets are widely promoted and expected to be a cleaner alternative fuel to unprocessed crop residues and rawcoal in rural China.However,the effectiveness of these dissemination programs is not well evaluated.In this field study,emission characteristics of burning strawpellets,rawcoal,and unprocessed corn cobs in heating stoveswere investigated in a pilot village in Northeast China.Emission measurements covering the whole combustion cycle(ignition,flaming,and smoldering phases)shows the promotion of improved heating stoves and straw pellets could reduce pollutant emissions(e.g.,SO_(2) and CO),but increase NO_(X) and PM_(2.5) emissions compared to the initial stove-fuel use pattern in the studied area.There is a significant variance in emission characteristics between different combustion phases.The normalized emission concentrations of the different stove-fuel combinations were higher than the limits in the Chinese national standard for heating stoves,indicating that the standard is not met for real-world emissions.Coal consumption was lower than official data.Household surveys were conducted to identify the barriers to fuel and stove access associated with existing promotion strategies,management,and policies.The pilot program was of the typical“subsidy-and-policy-dependence”pattern and was unlikely to be implemented on a large scale.Technological innovation,operational optimization,and proper policies considering the local socioeconomic factors are needed to sustain the promotion of biomass straw pellets and stoves.展开更多
Radio frequency identification technology is one of the main technologies of Internet of Things(IoT).Through the transmission and reflection of wireless radio frequency signals,non-contact identification is realized,a...Radio frequency identification technology is one of the main technologies of Internet of Things(IoT).Through the transmission and reflection of wireless radio frequency signals,non-contact identification is realized,and multiple objects identification can be realized.However,when multiple tags communicate with a singleton reader simultaneously,collision will occur between the signals,which hinders the successful transmissions.To effectively avoid the tag collision problem and improve the reading performance of RFID systems,two advanced tag identification algorithms namely Adaptive M-ary tree slotted Aloha(AMTS)based on the characteristics of Aloha-based and Query tree-based algorithms are proposed.In AMTS,the reader firstly uses the framed slotted Aloha protocol to map the tag set to different time slots,and then identify the collided tags using binary search method based on collision factor or mapping table.Both performance analysis and extensive experimental results indicate that our proposed algorithms significantly outperforms most existing anti-collision approaches in tag dense RFID systems.展开更多
Popular descriptive multivariate statistical method currently employed is the principal component analyses (PCA) method. PCA is used to develop linear combinations that successively maximize the total variance of a ...Popular descriptive multivariate statistical method currently employed is the principal component analyses (PCA) method. PCA is used to develop linear combinations that successively maximize the total variance of a sample where there is no known group structure. This study aimed at demonstrating the performance evaluation of pilot activated sludge treatment system by inoculating a strain of Pseudomonas capable of degrading malathion which was isolated by enrichment technique. An intensive analytical program was followed for evaluating the efficiency of biosimulator by maintaining the dissolved oxygen (DO) concentration at 4.0 mg/L. Analyses by high performance liquid chromatographic technique revealed that 90% of malathion removal was achieved within 29 h of treatment whereas COD got reduced considerably during the treatment process and mean removal efficiency was found to be 78%. The mean pH values increased gradually during the treatment process ranging from 7.36-8.54. Similarly the mean ammonia-nitrogen (NH3-N) values were found to be fluctuating between 19.425-28.488 mg/L, mean nitrite-nitrogen (NO3-N) ranging between 1.301- 2.940 mg/L and mean nitrate-nitrogen (NO3-N) ranging between 0.0071-0.0711 mg/L. The study revealed that inoculation of bacterial culture under laboratory conditions could be used in bioremediation of environmental pollution caused by xenobiotics. The PCA analyses showed that pH, COD, organic load and total malathion concentration were highly correlated and emerged as the variables controlling the first component, whereas dissolved oxygen, NO3-N and NH3-N governed the second component. The third component repeated the trend exhibited by the first two components.展开更多
基金the National Natural Science Foundation of China(No.31800595 and 31471906)the National Key Research and Development Program of China(2018YFD1000401)the Special Fund for Beijing Common Construction Project.
文摘The term‘ornamental plant’refers to all plants with ornamental value,which generally have beautiful flowers or special plant architectures.China is rich in ornamental plant resources and known as the“mother of gardens”.Genomics is the science of studying genomes and is useful for carrying out research on genome evolution,genomic variations,gene regulation,and important biological mechanisms based on detailed genome sequence information.Due to the diversity of ornamental plants and high sequencing costs,the progress of genome research on ornamental plants has been slow for a long time.With the emergence of new sequencing technologies and a reduction in costs since the whole-genome sequencing of the first ornamental plant(Prunus mume)was completed in 2012,whole-genome sequencing of more than 69 ornamental plants has been completed in<10 years.In this review,whole-genome sequencing and resequencing of ornamental plants will be discussed.We provide analysis with regard to basic data from whole-genome studies of important ornamental plants,the regulation of important ornamental traits,and application prospects.
基金supported by China national high-technology industrialized boosting plan(99-257)Emphasesresearch plan of science and technology of Yunnan ProvinceGovernment(97-023)emphases research plan of scienceand technology of Kunming City Government(98-016).
基金supported by the National Natural Science Foundation of China(No.41772240)the Key Research and Development program of Jiangsu Province(No.BE2021637).
文摘Ball milling is an environmentally friendly technology for the remediation of petroleumcontaminated soil(PCS),but the cleanup of organic pollutants requires a long time,and the post-remediation soil needs an economically viable disposal/reuse strategy due to its vast volume.The present paper develops a ball milling process under oxygen atmosphere to enhance PCS remediation and reuse the obtained carbonized soil(BCS-O)as wastewater treatment materials.The total petroleum hydrocarbon removal rates by ball milling under vacuum,air,and oxygen atmospheres are 39.83%,55.21%,and 93.84%,respectively.The Langmuir and pseudo second-order models satisfactorily describe the adsorption capacity and behavior of BCS-O for transition metals.The Cu^(2+),Ni^(2+),and Mn^(2+)adsorbed onto BCS-O were mainly bound to metal carbonates and metal oxides.Furthermore,BCS-O can effectively activate persulfate(PDS)oxidation to degrade aniline,while BCS-O loaded with transition metal(BCS-O-Me)shows better activation efficiency and reusability.BCS-O and BCS-O-Me activated PDS oxidation systems are dominated by^(1)O_(2)oxidation and electron transfer.The main active sites are oxygen-containing functional groups,vacancy defects,and graphitized carbon.The oxygen-containing functional groups and vacancy defects primarily activate PDS to generate^(1)O_(2)and attack aniline.Graphitized carbon promotes aniline degradation by accelerating electron transfer.The paper develops an innovative strategy to simultaneously realize efficient remediation of PCS and sequential reuse of the postremediation soil.
基金funded by the National Natural Science Foundation of China(Grant No.32271872).
文摘Over the past decades,the expansion of natu-ral secondary forests has played a crucial role in offsetting the loss of primary forests and combating climate change.Despite this,there is a gap in our understanding of how tree species’growth and mortality patterns vary with eleva-tion in these secondary forests.In this study,we analyzed data from two censuses(spanning a five-year interval)conducted in both evergreen broadleaved forests(EBF)and temperate coniferous forests(TCF),which have been recovering for half a century,across elevation gradients in a subtropical mountain region,Mount Wuyi,China.The results indicated that the relative growth rate(RGR)of EBF(0.028±0.001 cm·cm^(-1)·a^(-1))and the mortality rate(MR)(20.03%±1.70%)were 27.3%and 16.4%higher,respec-tively,than those of TCF.Interestingly,the trade-off between RGR and MR in EBF weakened as elevation increased,a trend not observed in TCF.Conversely,TCF consistently showed a stronger trade-off between RGR and MR compared to EBF.Generalized linear mixed models revealed that ele-vation influences RGR both directly and indirectly through its interactions with slope,crown competition index(CCI),and tree canopy height(CH).However,tree mortality did not show a significant correlation with elevation.Additionally,DBH significantly influenced both tree growth and mortal-ity,whereas and CH and CCI had opposite effects on tree growth between EBF and TCF.Our study underscores the importance of elevation in shaping the population dynamics and the biomass carbon sink balance of mountain forests.These insights enhance our understanding of tree species’life strategies,enabling more accurate predictions of forest dynamics and their response to environmental changes.
文摘Membrane fouling remains the primary economic barrier to the widespread implementation of membrane bioreactors (MBRs), despite the fact that they lead to the production of high-quality effluent. Operational conditions are critical factors influencing membrane fouling. This study aimed to investigate the simultaneous impacts of temperature and hydraulic retention time (HRT) variations on membrane fouling. Experiments were conducted at three different temperatures (18°C, 25°C, and 32°C) and HRTs (6 h, 9 h, and 15 h). The results demonstrated that increases in both temperature and HRT contributed to a reduction in membrane fouling. Additionally, a positive interaction between temperature and HRT was observed in the linear slope variation of membrane permeation, with temperature variations exerting a greater influence on membrane fouling than HRT variations. Fouling factor analysis revealed that increases in temperature and HRT led to decreased concentrations of soluble microbial products (SMP) and extracellular polymeric substances (EPS), particularly carbohydrates, in the activated sludge. Analyses of the cake layer of the membrane indicated that increasing temperature and HRT reduced EPS levels, particularly polysaccharides and proteins;altered primary protein structure;and increased the mean particle size distribution. Ultimately, these changes led to reductions in both reversible and irreversible hydraulic resistances. This study highlights the importance of optimizing operational parameters such as temperature and HRT to enhance membrane performance and treatment efficiency in MBR systems while mitigating fouling.
基金Sahand University of Technology and Utrecht University for the project's financial supportthe Iran Nanotechnology Initiative Council for their additional financial assistance。
文摘A promising structured catalyst was developed through proper coating of boron-modified ZSM-5 using SiO_(2) and Al_(2)O_(3)-containing binders to investigate catalytic performance as well as mechanical stability of the catalyst in a monolithic reactor.The reference and boron-modified ZSM-5 catalysts were synthesized by hydrothermal route.The adherence strength of catalyst samples was characterized using ultrasonic vibration method and FESEM analysis.A series of comparative performance tests were also conducted in two reactors,including monolithic and extruded catalysts for the production of propylene from methanol at atmospheric pressure,reaction temperatures of 500℃,and methanol weight hourly space velocity(WHSV)of 1.5 h^(-1).Initial findings demonstrate that applying the B-modified ZSM-5zeolite in a monolith reactor increased propylene selectivity by about 26%compared to the conventional extruded ZSM-5 catalyst.Moreover,silica bonded to the B-ZSM-5 catalyst in the monolithic reactor,owning sufficient adhesion properties;the proposed catalyst showed the best catalytic performance,with not only a high propylene selectivity(58.5%)but also a large propylene/ethylene(P/E)ratio(8.6).The findings attained in this work would be useful in the production of new efficient catalysts based on a zeolite-coated honeycomb monolith in the methanol-to-propylene process.
文摘Bioleaching was examined for copper extraction from a low grade ore using mesophilic and moderate thermophilic bacteria. Five equal size columns were used for the leaching of the ore. Sulfuric acid solution with a flow rate of 3.12 L·m-2·h-1 and pH 1.5 passed through each column continuously for 90 d. In the first and the second column, bioleaching was performed without agglomeration of the ore and on the agglomerated ore, respectively. 28wt% of the copper was extracted in the first column after 40 d, while this figure was 38wt% in the second column. After 90 d, however, the overall extractions were almost the same for both of them. Bioleaching with mesophilic bacteria was performed in the third column without agglomeration of the ore and in the fourth column on the agglomerated ore. After 40 d, copper extractions in the third and the fourth columns were 62wt% and 70wt%, respectively. Copper extractions were 75wt% for both the columns after 90 d. For the last column, bioleaching was performed with moderate thermophilic bacteria and agglomerated ore. Copper extractions were 80wt% and 85wt% after 40 and 90 d, respectively. It was concluded that crushing and agglomeration of the ore using bacteria could enhance the copper extraction considerably.
基金supported by the National Natural Science Foundation of China (Nos.51709157 and U20A20146)the Youth Interdisciplinary Science and Innovative Research Groups of Shandong University (No.2020QNQT014)。
文摘The pollution of antibiotics commonly existed throughout the entire aquaculture process,but the residues of antibiotics at different aquaculture stages have rarely been studied.This study investigated the occurrence,distribution and risk assessment of antibiotics at different aquaculture stages (the non-aquaculture stage,the early aquaculture stage,the middle aquaculture stage,and the late aquaculture stage) in two typical marine aquaculture areas(Mahegang River and Dingzi Bay) surrounding the Yellow Sea.Fluoroquinolones and tetracyclines were commonly used antibiotics in the aquaculture of these areas with high detection frequencies (17%to 83%).Compared among four aquaculture stages,the highest concentration of antibiotics (9032.08 ng/L) in aquaculture ponds was detected at the late aquaculture stage.And the antibiotic pollution level of natural water was directly related to the aquaculture stages.Similarly,at the aquaculture stages,the detection frequency of antibiotics in sediments was higher than that at the non-aquaculture stage.Based on the correlation analysis,the concentration of main antibiotics in water showed a positive correlation with total nitrogen (p<0.05) and chlorophyll a (p<0.01),while it showed a negative correlation with salinity (p<0.01) in coastal water of the Dingzi Bay.According to the risk assessment,with the development of aquaculture stages,the selection pressure of fluoroquinolones and tetracyclines on resistant bacteria had increased.And the ecological risks caused by sulfonamides and tetracyclines to aquatic organisms had also increased markedly.Overall,this study may provide a reference for formulating regulatory policies regarding antibiotic use at different aquaculture stages.
基金Supported by the National Natural Science Foundation of China(Nos.41320104008,41030858,41306069)the National Natural Science Foundation for Creative Research Groups(No.41221004)+3 种基金the Specialized Research Fund for the Doctoral Program of Higher Education of China(No.20110132120010)the Cheung Kong Scholars Program of Chinathe Taishan Scholar Program of Shandong Provincethe Fundamental Research Funds for the Central Universities
文摘The distributions of dimethylsulfide (DMS) and its precursor dimethylsulfoniopropionate (DMSP) in surface water of the Yellow Sea and the Bohai Sea were studied during June 2011. The mean concentrations and ranges of DMS, dissolved DMSP (DMSPd), and particulate DMSP (DMSPp) in surface waters were 6.85 (1.60-12.36), 7.25 (2.28-19.05) and 61.87 (6.28-224.01) nmol/L, respectively. There were strong correlations between DMSPp and chlorophyll a in the Bohai Sea and the North Yellow Sea, respectively, and concentrations of DMS and DMSP were high, with a relatively high proportion of dinoflagellates, in the region of the South Yellow Sea Cold Water Mass. Results show that phytoplankton biomass and species composition were important factors that controlled the distribution of DMS and DMSP. Complex environmental factors, including nutrients, transparency, and terrestrial runoff, might also influence the variability in DMS and DMSP. Biological production and consumption rates of DMS in the Bohai Sea were higher than those in the Yellow Sea. DMS production rates were closely correlated with DMSPd concentrations. DMS and DMSP exhibited obvious diel variations, with high concentrations occurring in the late afternoon (16:00-19:00) and low concentrations occurring during the night, implying that the intensity of solar radiation had a significant influence on these variations. Size distributions of chlorophyll a and DMSPp were also investigated and large nanoplankton (5-20 μm), mainly diatoms, contributed significantly to chlorophyll a and DMSPp at most stations. The average sea-to-air flux of DMS in the study area was estimated to be 11.07 μmol/(m^2·d) during the summer.
基金This research was supported by The People’s Republic of China Ministry of Science and Technology[2018YFF0213606-03(Mu Y.,Hu T.L.,Gong H.,Li S.J.and Sun Y.H.)http://www.most.gov.cn]the Science and Technology Department of Jilin Province[20160623016TC,20170204017NY,20170204038NY(Hu T.L.,Gong H.and Li S.J.)http://kjt.jl.gov.cn],and the ScienceTechnology Bureau of Changchun City[18DY021(Mu Y.,Hu T.L.,Gong H.,and Sun Y.H.)http://kjj.changchun.gov.cn].
文摘In large-scale deer farming image analysis,K-means or maximum between-class variance(Otsu)algorithms can be used to distinguish the deer from the background.However,in an actual breeding environment,the barbed wire or chain-link fencing has a certain isolating effect on the deer which greatly interferes with the identification of the individual deer.Also,when the target and background grey values are similar,the multiple background targets cannot be completely separated.To better identify the posture and behaviour of deer in a deer shed,we used digital image processing to separate the deer from the background.To address the problems mentioned above,this paper proposes an adaptive threshold segmentation algorithm based on color space.First,the original image is pre-processed and optimized.On this basis,the data are enhanced and contrasted.Next,color space is used to extract the several backgrounds through various color channels,then the adaptive space segmentation of the extracted part of the color space is performed.Based on the segmentation effect of the traditional Otsu algorithm,we designed a comparative experiment that divided the four postures of turning,getting up,lying,and standing,and successfully separated multiple target deer from the background.Experimental results show that compared with K-means,Otsu and hue saturation value(HSV)+K-means,this method is better in performance and accuracy for adaptive segmentation of deer in artificial breeding scenes and can be used to separate artificially cultivated deer from their backgrounds.Both the subjective and objective aspects achieved good segmentation results.This article lays a foundation for the effective identification of abnormal behaviour in sika deer.
基金the Innovation-Driven Project of Central South University(No.2019CX033)the National Natural Science Foundation of China(No.51904344)。
文摘Lithium–sulfur(Li-S)batteries have been considered as promising candidates for large-scale high energy density devices due to the potentially high energy density,low cost,and more pronounced ecological compatibility.However,the complex Li-S conversion reactions,unsatisfactory battery performance,and unsafe metallic Li anode restrict the development of Li-S batteries to achieve commercialization.This review mainly focuses on three aspects which are the remaining challenges,recent advances,and applications in Li-S batteries.Firstly,this review portrays Li-S conversion chemistry involving the multi-step and multi-electron reaction mechanism,as well as the remaining challenges.Then,the scientific strategies and very recent advances of the cathode,electrolyte,lithium anode,and other constituent parts of Li-S batteries are detailly summed up,as well as their advantages and limitations.For the sake of promoting the Li-S batteries practicalization,next section is primarily concerned with problems,the corresponding solutions,and application scenarios of practical pouch cells.Finally,the important findings as guidelines and some future directions as trends for developing emerging Li-S batteries are briefly summarized.
基金supported by the 812 Geological Teamthe Tongling Nonferrous Metals Group Holdings Co.,Ltd+1 种基金financially supported by the National Key Research and Development Program of China(2016YFC0600206)the Major Research Program of the National Natural Science Foundation of China(91962218)。
文摘The Yaojialing deposit is the first large-scale Zn-Au-Cu polymetallic skarn deposit located in the Shatanjiao ore field of the Tongling area in the Middle-Lower Yangtze belt.It has distinct metallogenic characteristics and is clearly different from the known skarn Cu-Au deposits in the Tongling area and the Middle-Lower Yangtze belt.Previous studies of the Yaojialing deposit have included rock geochemistry,alteration and mineralization characteristics,as well as metallogenesis and metallogenic models.However,there are still numerous problems concerning the coexistence of multiple elements,metallogenetic specialization of the magma and the metallogenic model.In this study,using the latest production exploration work on the deposit,we investigated the Yaojialing deposit including its geological characteristics,petrography,LA-ICP MS zircon U-Pb dating and whole rock geochemistry.Two kinds of magmatic rocks have been distinguished for the first time in the deposit,amongst which the granodiorite porphyry exposed on the surface of the mining area,which is the host rock of the veined lead-zinc ore body,is the wall-rock intrusion;and the deep concealed quartz monzonite porphyry is the causative intrusion,the distribution of orebodies and wall-rock alteration characteristics showing regular zoning around the quartz monzonite porphyry.The^(206)Pb/^(238)U weighted average age of the granodiorite porphyry is 140.2±1.0 Ma(MSWD=0.85,n=13)by LA-ICP MS zircon U-Pb dating,while the quartz monzonite porphyry is 138.9±1.2 Ma(MSWD=0.60,n=16),which is consistent with petrographic evidence.The geochemical characteristics show that the quartz monzonite porphyry is a high-K calc-alkaline series peraluminous rock.The trace element characteristics show that the quartz monzonite porphyry is enriched in LILE such as K,Rb,Sr,Ba and LREE,yet depleted in HFSE such as Nb,Ta,P and Ti.The Yaojialing deposit shows the mineralization characteristics of proximal skarn and distal skarn,having the common characteristics of'multi-storey'and'Trinity'metallogenic models.
基金supported by the National Natural Science Foundation of China (Grant No. 32071816)the Opening Preject of State Key Laboratory of Tree Genetics and Breeding (Grant No. K2021101)Special Fund for Beijing Common Construction Project。
文摘Prunus mume is an important woody plant that has high ornamental and economic value, widely distributed and used in landscape architecture in East Asia. In plants, basic(region) leucine zipper(bZIP) transcription factors play important regulatory roles in growth, development,dormancy and abiotic stress. To date, bZIP transcription factors have not been systematically studied in P. mume. In this study, 49 bZIP genes were first identified in P. mume, and the PmbZIP family was divided into 12 groups according to the grouping principles for the Arabidopsis thaliana bZIP family. For the first time, we constructed a detailed model of the PmbZIP domains(R-x_(3)–N-(x)_7-R/K-x_(2)-K-x_(6)-L-x_(6)-L-_(6)-L). Phylogenetic and synteny analyses showed that PmbZIPs duplication events might have occurred during the large-scale genome duplication events. A relatively short time of speciation and the finding that 91.84% of the bZIP genes formed orthologous pairs between P. mume and Prunus armeniaca provided evidence of a close relationship. Gene expression patterns were analysed in different tissues and periods, indicating that PmbZIP genes with the same motifs exhibited similar expression patterns. The gene expression results showed that PmbZIP31/36/41 genes played a more prominent role in the response to freezing stress than cold stress. The expression level of almost all subset Ⅲ genes was upregulated under freezing treatment, especially after cold exposure. We analysed the gene expression patterns of PmbZIP12/31/36/41/48 and their responses to low-temperature stress, which provided useful resources for future studies on the cold/freezing-tolerant molecular breeding of P. mume.
基金The authors are grateful for the grants provided by the National Natural Science Foundation of China(Grant no.52274309)the Postgraduate Scientific Research Innovation Project of Hunan Province(Grant no.CX20220183)Simin Li thanks the National Natural Science Foundation of China(Grant no.52204327).
文摘Hard carbon is regarded as a promising anode candidate for sodium-ion batteries due to its low cost,relatively low working voltage,and satisfactory specific capacity.However,it still remains a challenge to obtain a high-performance hard carbon anode from cost-effective carbon sources.In addition,the solid electrolyte interphase(SEI)is subjected to continuous rupture during battery cycling,leading to fast capacity decay.Herein,a lignin-based hard carbon with robust SEI is developed to address these issues,effectively killing two birds with one stone.An innovative gas-phase removal-assisted aqueous washing strategy is developed to remove excessive sodium in the precursor to upcycle industrial lignin into high-value hard carbon,which demonstrated an ultrahigh sodium storage capacity of 359 mAh g^(-1).It is found that the residual sodium components from lignin on hard carbon act as active sites that controllably regulate the composition and morphology of SEI and guide homogeneous SEI growth by a near-shore aggregation mechanism to form thin,dense,and organic-rich SEI.Benefiting from these merits,the as-developed SEI shows fast Na+transfer at the interphases and enhanced structural stability,thus preventing SEI rupture and reformation,and ultimately leading to a comprehensive improvement in sodium storage performance.
基金financially supported by the National Natural Science Foundation of China(No.52170049).
文摘A continuous flow bioreactor was operated for 300 days to investigate partial nitritation(PN)of mature landfill leachate,establishing the long-term performance of the system in terms of the microbial community composition,evolution,and interactions.The stable operation phase(31-300 d)began after a 30 days of start-up period,reaching an average nitrite accumulation ratio(NAR)of 94.43%and a ratio of nitrite nitrogen to ammonia nitrogen(NO_(2)^(−)-N/NH_(4)^(+)-N)of 1.16.Some fulvic-like and humic-like compounds and proteins were effectively degraded in anaerobic and anoxic tanks,which was consistent with the corresponding abundance of methanogens and syntrophic bacteria in the anaerobic tank,and organic matter degrading bacteria in the anoxic tank.The ammonia-oxidizing bacteria(AOB)Nitrosomonas was found to be the key functional bacteria,exhibiting an increase in abundance from 0.27%to 6.38%,due to its collaborative interactions with organic matter degrading bacteria.In-situ inhibition of nitrite-oxidizing bacteria(NOB)was achieved using a combination of free ammonia(FA)and free nitrous acid(FNA),low dissolved oxygen(DO)with fewer bioavailable organics conditions were employed to maintain stable PN and a specific ratio of NO_(2)^(−)-N/NH_(4)^(+)-N,without an adverse impact on AOB.The synergistic relationships between AOB and both denitrifying bacteria and organic matter degrading bacteria,were found to contribute to the enhanced PN performance and microbial community structure stability.These findings provide a theoretical guidance for the effective application of PN-Anammox for mature landfill leachate treatment.
基金supported by National Key R&D Program of China(2019YFD1001004,2019YFD1000402)the program for Science and Technology of Beijing(Z181100002418006)the Special Fund for Beijing Common Construction Project.
文摘Crape myrtle(Lagerstroemia indica)is a globally used ornamental woody plant and is the representative species of Lagerstroemia.However,studies on the evolution and genomic breeding of L.indica have been hindered by the lack of a reference genome.Here we assembled the first high-quality genome of L.indica using PacBio combined with Hi-C scaffolding to anchor the 329.14-Mb genome assembly into 24 pseudochromosomes.We detected a previously undescribed independent whole-genome triplication event occurring 35.5 million years ago in L.indica following its divergence from Punica granatum.After resequencing 73 accessions of Lagerstroemia,the main parents of modern crape myrtle cultivars were found to be L.indica and L.fauriei.During the process of domestication,genetic diversity tended to decrease in many plants,but this was not observed in L.indica.We constructed a high-density genetic linkage map with an average map distance of 0.33 cM.Furthermore,we integrated the results of quantitative trait locus(QTL)using genetic mapping and bulk segregant analysis(BSA),revealing that the major-effect interval controlling internode length(IL)is located on chr1,which contains CDL15,CRG98,and GID1b1 associated with the phytohormone pathways.Analysis of gene expression of the red,purple,and white flower-colour flavonoid pathways revealed that differential expression of multiple genes determined the flower colour of L.indica,with white flowers having the lowest gene expression.In addition,BSA of purple-and green-leaved individuals of populations of L.indica was performed,and the leaf colour loci were mapped to chr12 and chr17.Within these intervals,we identified MYB35,NCED,and KAS1.Our genome assembly provided a foundation for investigating the evolution,population structure,and differentiation of Myrtaceae species and accelerating the molecular breeding of L.indica.
基金supported by the Programme for Science and Technology of Beijing(No.Z181100002418006)the Special Fund for the Beijing Common Construction Project.
文摘Plant architecture includes vital traits that influence and benefit crops,and economically important trees.Different plant architectures provide natural beauty.Weeping ornamental plants are aesthetically appealing to people.The regulatory mechanism controlling the weeping trait is poorly understood in crape myrtle.To investigate the weeping trait mechanism,transcriptional profiling of different organs in weeping and upright crape myrtle was performed based on phenotype.Phenotypic and histological analyses demonstrated that endodermal cells were absent,and that new shoot phenotypes could be rescued by the GA3 treatment of weeping plants.The transcriptional analysis and coexpression network analysis(WGCNA)of differentially expressed genes indicated that GA synthesis and signal transduction pathways play a role in weeping traits.When the expression level of a negative element of GA signaling,LfiGRAS1,was reduced by virus-induced gene silencing(VIGS),new branches grew in infected plants in a negatively geotropic manner.An integrated analysis implied that GA had a strong influence on weeping crape myrtle by interacting with other factors.This study helps to elucidate the mechanism governing the weeping trait and can improve the efficiency of breeding in Lagerstroemia.
基金supported by the Ministry of Science and Technology of China(No.2017YFC0211400)and the China Office of Clean Air Asia.
文摘Straw pellets are widely promoted and expected to be a cleaner alternative fuel to unprocessed crop residues and rawcoal in rural China.However,the effectiveness of these dissemination programs is not well evaluated.In this field study,emission characteristics of burning strawpellets,rawcoal,and unprocessed corn cobs in heating stoveswere investigated in a pilot village in Northeast China.Emission measurements covering the whole combustion cycle(ignition,flaming,and smoldering phases)shows the promotion of improved heating stoves and straw pellets could reduce pollutant emissions(e.g.,SO_(2) and CO),but increase NO_(X) and PM_(2.5) emissions compared to the initial stove-fuel use pattern in the studied area.There is a significant variance in emission characteristics between different combustion phases.The normalized emission concentrations of the different stove-fuel combinations were higher than the limits in the Chinese national standard for heating stoves,indicating that the standard is not met for real-world emissions.Coal consumption was lower than official data.Household surveys were conducted to identify the barriers to fuel and stove access associated with existing promotion strategies,management,and policies.The pilot program was of the typical“subsidy-and-policy-dependence”pattern and was unlikely to be implemented on a large scale.Technological innovation,operational optimization,and proper policies considering the local socioeconomic factors are needed to sustain the promotion of biomass straw pellets and stoves.
基金supported by The People’s Republic of China Ministry of Science and Technology[2018YFF0213606-03(Mu Y.,Hu T.L.,Gong H.,Li S.J.and Sun Y.H.)http://www.most.gov.cn]the Science and Technology Department of Jilin Province[20160623016TC,20170204017NY,20170204038NY,20200402006NC(Mu Y.,Hu T.L.,Gong H.and Li S.J.)http://kjt.jl.gov.cn]the Science and Technology Bureau of Changchun City[18DY021(Mu Y.,Hu T.L.,Gong H.,and Sun Y.H.)http://kjj.changchun.gov.cn].
文摘Radio frequency identification technology is one of the main technologies of Internet of Things(IoT).Through the transmission and reflection of wireless radio frequency signals,non-contact identification is realized,and multiple objects identification can be realized.However,when multiple tags communicate with a singleton reader simultaneously,collision will occur between the signals,which hinders the successful transmissions.To effectively avoid the tag collision problem and improve the reading performance of RFID systems,two advanced tag identification algorithms namely Adaptive M-ary tree slotted Aloha(AMTS)based on the characteristics of Aloha-based and Query tree-based algorithms are proposed.In AMTS,the reader firstly uses the framed slotted Aloha protocol to map the tag set to different time slots,and then identify the collided tags using binary search method based on collision factor or mapping table.Both performance analysis and extensive experimental results indicate that our proposed algorithms significantly outperforms most existing anti-collision approaches in tag dense RFID systems.
文摘Popular descriptive multivariate statistical method currently employed is the principal component analyses (PCA) method. PCA is used to develop linear combinations that successively maximize the total variance of a sample where there is no known group structure. This study aimed at demonstrating the performance evaluation of pilot activated sludge treatment system by inoculating a strain of Pseudomonas capable of degrading malathion which was isolated by enrichment technique. An intensive analytical program was followed for evaluating the efficiency of biosimulator by maintaining the dissolved oxygen (DO) concentration at 4.0 mg/L. Analyses by high performance liquid chromatographic technique revealed that 90% of malathion removal was achieved within 29 h of treatment whereas COD got reduced considerably during the treatment process and mean removal efficiency was found to be 78%. The mean pH values increased gradually during the treatment process ranging from 7.36-8.54. Similarly the mean ammonia-nitrogen (NH3-N) values were found to be fluctuating between 19.425-28.488 mg/L, mean nitrite-nitrogen (NO3-N) ranging between 1.301- 2.940 mg/L and mean nitrate-nitrogen (NO3-N) ranging between 0.0071-0.0711 mg/L. The study revealed that inoculation of bacterial culture under laboratory conditions could be used in bioremediation of environmental pollution caused by xenobiotics. The PCA analyses showed that pH, COD, organic load and total malathion concentration were highly correlated and emerged as the variables controlling the first component, whereas dissolved oxygen, NO3-N and NH3-N governed the second component. The third component repeated the trend exhibited by the first two components.