Dear Editor,Aiming at the consensus tracking problem of a class of unknown heterogeneous nonlinear multiagent systems(MASs)with input constraints,a novel data-driven iterative learning consensus control(ILCC)protocol ...Dear Editor,Aiming at the consensus tracking problem of a class of unknown heterogeneous nonlinear multiagent systems(MASs)with input constraints,a novel data-driven iterative learning consensus control(ILCC)protocol based on zeroing neural networks(ZNNs)is proposed.First,a dynamic linearization data model(DLDM)is acquired via dynamic linearization technology(DLT).展开更多
As a frequently-observed phenomenon in the northern South China Sea(nSCS),subsurface chlorophyll maximum(SCM)evolution from summer to winter remains unclear,neither the associated hydrographic control.In this study,on...As a frequently-observed phenomenon in the northern South China Sea(nSCS),subsurface chlorophyll maximum(SCM)evolution from summer to winter remains unclear,neither the associated hydrographic control.In this study,on the basis of in-situ data of fall-season cruises in 2004–2006,we characterized the depth,thickness and intensity of the SCM in the nSCS using a general Gaussian-function fitting approach,and investigated a linkage to the corresponding ocean vertical buoyance properties.Our results show that the SCM becomes deeper,thicker and less intense offshore-wards in the nSCS during fall seasons.In parallel,a correlation between the SCM variation and mixed layer depth exists in the nSCS,and it becomes pronounced in the shelf region compared to the slope and basin areas in autumn.Physically,once warmer surface ocean and thus stronger thermo-determined stratification,the SCM layer goes deeper and becomes thicker and less intense in the nSCS,especially in the shelf area of the nSCS.Moreover,the impact of water temperatures at deeper layers on the vertical stratification exerts more consequent roles on the spatial variability of SCM,compared to surface temperatures in the nSCS.Specifically,the isotherm line of 22℃ acts as crucial indicator for variations of the SCM in the nSCS during autumns.展开更多
Variations in ocean mixed layer depth(MLD)show a significant impact on energy balance in the global climate systems and marine ecosystems.At present,the accuracy of modeling MLD,especially in the region with complex o...Variations in ocean mixed layer depth(MLD)show a significant impact on energy balance in the global climate systems and marine ecosystems.At present,the accuracy of modeling MLD,especially in the region with complex ocean dynamics,remains a challenge,thus calling for an emergency using artificial intelligence approach to improve the assessment of the MLD.A novel convolutional neural network model was developed based on a dual-attention module(DA-CNN)to estimate the MLD in the Bay of Bengal(BoB)by integrating multi-source remote sensing data and Argo gridded data.Compared with the original CNN model,the DA-CNN model exhibits superior performance with notable improvements in the annual average root mean square error(RMSE)and R2 values by 13.0%and 8.4%,respectively,while more accurately capturing the seasonal variations in MLD.Moreover,the results using the DA-CNN model show minimum RMSE and maximum R2 values,in comparison to the calculation by the random forest,artificial neural network model,and the hybrid coordinate ocean model.Accordingly,our findings suggest that the newly developed DA-CNN model provides an effective advantage in studying the MLD and the associated ocean processes.展开更多
A growing body of evidence suggests that the gut microbiota contributes to the development of neurodegenerative diseases via the microbiota-gut-brain axis.As a contributing factor,microbiota dysbiosis always occurs in...A growing body of evidence suggests that the gut microbiota contributes to the development of neurodegenerative diseases via the microbiota-gut-brain axis.As a contributing factor,microbiota dysbiosis always occurs in pathological changes of neurodegenerative diseases,such as Alzheimer’s disease,Parkinson’s disease,and amyotrophic lateral sclerosis.High-throughput sequencing technology has helped to reveal that the bidirectional communication between the central nervous system and the enteric nervous system is facilitated by the microbiota’s diverse microorganisms,and for both neuroimmune and neuroendocrine systems.Here,we summarize the bioinformatics analysis and wet-biology validation for the gut metagenomics in neurodegenerative diseases,with an emphasis on multi-omics studies and the gut virome.The pathogen-associated signaling biomarkers for identifying brain disorders and potential therapeutic targets are also elucidated.Finally,we discuss the role of diet,prebiotics,probiotics,postbiotics and exercise interventions in remodeling the microbiome and reducing the symptoms of neurodegenerative diseases.展开更多
Cycas panzhihuaensis L.Zhou & S.Y.Yang(Cycadaceae) is an endangered gymnosperm species endemic to the dry-hot valley of the Jinsha River basin in southwest China.Although the wild C.panzhihuaensis population from ...Cycas panzhihuaensis L.Zhou & S.Y.Yang(Cycadaceae) is an endangered gymnosperm species endemic to the dry-hot valley of the Jinsha River basin in southwest China.Although the wild C.panzhihuaensis population from Panzhihua Cycad Natural Reserve is well protected and its genetic diversity has been well assessed,the genetic characteristics of populations outside the nature reserve,which face larger risks of extinction,remain unknown.Furthermore,the population genetics and historical dynamics of this endemic and endangered species have not been examined across its entire range.In this study,to analyze the genetic diversity,phylogeographical structure and demographic history of C.panzhihuaensis from all its seven known locations,we sequenced and compared molecular data from chloroplastic DNA(psbA-trnH,psbM-trnD,and trnS-trnG),single-copy nuclear genes(PHYP,AC5,HSP70,and AAT) from 61 individuals,as well as 11 nuclear micro satellite loci(SSR) from 102 individuals.We found relatively high genetic diversity within populations and high genetic differentiation among populations of C.panzhihuaensis,which is consistent with the patterns of other Asian inland cycads.Although no significant phylogeographical structure was detected,we found that small and unprotected populations possess higher genetic diversity and more unique haplotypes,which revises our understanding of diversity within this species and deserves due attention.Analysis of demographic dynamics suggest that human activity might be the key threat to C.panzhihuaensis.Based on the genetic characterization of C.panzhihuaensis,we propose several practical guidelines for the conservation of this species,especially for the populations with small sizes.展开更多
Genera Lamiophlomis and Paraphlomis were originally separated from genus Phlomis s.1. on the basis of particular morphological characteristics. However, their relationship was highly contentious, as evidenced by the l...Genera Lamiophlomis and Paraphlomis were originally separated from genus Phlomis s.1. on the basis of particular morphological characteristics. However, their relationship was highly contentious, as evidenced by the literature. In the present paper, the systematic positions of Lamiophlomis, Paraphlomis, and their related genera were assessed based on nuclear internal transcribed spacer （ITS） and chloroplast rpl16 and trnL-F sequence data using maximum parsimony （MP） and Bayesian methods. and outgroup were sampled. Analyses of both separate In total, 24 species representing six genera of the ingroup and combined sequence data were conducted to resolve the systematic relationships of these genera. The results reveal that Lamiophlomis is nested within Phlomis sect. Phlomoides and its generic status is not supported. With the inclusion ofLamiophlomis rotata in sect. Phlomoides, sections Phlomis and Phlomoides of Phlomis were resolved as monophyletic. Paraphlomis was supported as an independent genus. However, the resolution of its monophyly conflicted between MP and Bayesian analyses, suggesting the need for expended sampling and further evidence.展开更多
Magnolia biondii Pamp.(Magnoliaceae,magnoliids)is a phylogenetically,economically,and medicinally important ornamental tree species widely grown and cultivated in the north-temperate regions of China.Determining the g...Magnolia biondii Pamp.(Magnoliaceae,magnoliids)is a phylogenetically,economically,and medicinally important ornamental tree species widely grown and cultivated in the north-temperate regions of China.Determining the genome sequence of M.biondii would help resolve the phylogenetic uncertainty of magnoliids and improve the understanding of individual trait evolution within the Magnolia genus.We assembled a chromosome-level reference genome of M.biondii using~67,~175,and~154Gb of raw DNA sequences generated via Pacific Biosciences single-molecule real-time sequencing,10X Genomics Chromium,and Hi-C scaffolding strategies,respectively.The final genome assembly was~2.22Gb,with a contig N50 value of 269.11 kb and a BUSCO complete gene percentage of 91.90%.Approximately 89.17%of the genome was organized into 19 chromosomes,resulting in a scaffold N50 of 92.86Mb.The genome contained 47,547 protein-coding genes,accounting for 23.47%of the genome length,whereas 66.48%of the genome length consisted of repetitive elements.We confirmed a WGD event that occurred very close to the time of the split between the Magnoliales and Laurales.Functional enrichment of the Magnolia-specific and expanded gene families highlighted genes involved in the biosynthesis of secondary metabolites,plant–pathogen interactions,and responses to stimuli,which may improve the ecological fitness and biological adaptability of the lineage.Phylogenomic analyses revealed a sister relationship of magnoliids and Chloranthaceae,which are sister to a clade comprising monocots and eudicots.The genome sequence of M.biondii could lead to trait improvement,germplasm conservation,and evolutionary studies on the rapid radiation of early angiosperms.展开更多
Phytochemical investigation of the aerial parts of the monotypic plant,Musella lasiocarpa,led to the isolation of four rare bicyclic diarylheptanoids,musellarins B-E(2-5),two new phenylphenalenones,2-methoxy-9-(3′,4...Phytochemical investigation of the aerial parts of the monotypic plant,Musella lasiocarpa,led to the isolation of four rare bicyclic diarylheptanoids,musellarins B-E(2-5),two new phenylphenalenones,2-methoxy-9-(3′,4′-dihydroxyphenyl)-1H-phenalen-1-one(9),2-methoxy-9-(3′-methoxy-4′-hydroxyphenyl)-1H-phenalen-1-one(10),a new acenaphtylene derivative,trans-(1S,2S)-3-(4′-methoxyphenyl)-acenaphthene-1,2-diol(13),and two new sucrose esters,1,2′,3′,4′,6′-O-pentaacetyl-3-O-trans-p-coumaroylsucrose(16),1,2′,3′,4′,6′-O-pentaacetyl-3-O-cis-p-coumaroylsucrose(17),together with nine known compounds.In addition,(4E,6E)-1-(3′,4′-dihydroxyphenyl)-7-(4′′-hydroxyphenyl)-hepta-4,6-dien-3-one(15)was isolated for the first time from a natural source.The structures of new compounds were elucidated by analysis of their spectroscopic data.Compounds 2,6,8-10,12,and 14 were cytotoxic toward several of the human tumor cell lines(HL-60,SMMC-7721,A-549,MCF-7,and SW480).Of these,the new compound 9 was the most potent one,with IC50 values of 5.8,10.3,6.3,3.3,and 2.3μM,respectively.展开更多
Geological activities and climate oscillations during the Quaternary period profoundly impacted the distribution of species in Southwest China. Some plant species may be harbored in refugia, such as the dry-hot valley...Geological activities and climate oscillations during the Quaternary period profoundly impacted the distribution of species in Southwest China. Some plant species may be harbored in refugia, such as the dry-hot valleys of Southwest China. Cycas chenii X. Gong & W. Zhou, a critically endangered cycad species, which grows under the canopy in subtropical evergreen broad-leaved forests along the upstream drainage area of the Red River, is endemic to this refugium. In this study, 60 individuals of C. chenii collected from six populations were analyzed by sequencing two chloroplast intergenic spacers(cp DNA:psb A-trn H and trn L-trn F) and two nuclear genes(PHYP and RBP-1). Results showed high genetic diversity at the species level, but low within-population genetic diversity and high interpopulation genetic differentiation. A Bayesian phylogenetic tree based on cp DNA showed that five chloroplast haplotypes were clustered into two clades, which corresponds to the division of the western and eastern bank of the Red River. These data indicate a possible role for the Red River as a geographic barrier to gene flow in C. chenii.Based on our findings, we propose appropriate in situ and ex situ conservation strategies for C. chenii.展开更多
Placenta accreta spectrum disorder (PASD) and placenta previa (PP) are two of the mosthideous obstetric complications which are usually associated with a history of cesarean section(CS). Moreover, women with PASD, PP ...Placenta accreta spectrum disorder (PASD) and placenta previa (PP) are two of the mosthideous obstetric complications which are usually associated with a history of cesarean section(CS). Moreover, women with PASD, PP and/or a cesarean scarred uterus are more likely to haveadverse pregnancy outcomes, including blood transfusion, hysterectomy, pelvic organs damage,postpartum hemorhage, disseminated intravascular coagulation, multi-organ dysfunction syndromeand even maternal or fetal death. This study aimed to investigate the efficacy of precesareaninternal iliac artery balloon catheterization (BC) for managing severe hemorhage caused by PASDand PP with a history of CS. This participant-assigned interventional study was conducted inTongji Hospital. We recruited 128 women with suspected PASD, PP and a history of CS. Womenin the BC group accepted precesarean BC of bilateral internal iliac arteries before the scheduledcesarean delivery. Women in the control group underwent a conventional cesarean delivery.Intraoperative hemorrhage, transfusion volume, radiation dose, exposure time, complicationsand neonatal outcomes were discussed. There were significant differences in calculated bloodloss (CBL) between BC group and control group (1015.0±144.9 vs. 1467.0±171.0 mL, P=0.04).Precesarean BC could reduce intraoperative red blood cell (RBC) transfusion as compared withcontrol group (799.5±136.1 vs. 1286.0±161.6 mL, P=0.02) and lessen the rate of using bloodproducts (57.1% vs. 76.4%, P=0.02). The incidence of hysterectomy was also lower in BC groupthan in control group. Postpartum outcomes showed no significant differences between the twogroups, except that postoperation hospitalization was longer in BC group than in control group(6.7±0.4 vs. 5.8±0.2 days, P=0.03). Precesarean BC of internal iliac artery is an effective methodfor managing severe hemorrhage caused by PASD and PP with a cesarean scarred uterus, as it couldreduce intraoperative blood loss, lessen intraoperative RBC transfusions and potentially decreasehysterectomies.展开更多
Compared with traditional genetic markers,genomic approaches have proved valuable to the conservation of endangered species.Paeonia ludlowii having rarely and pure yellow flowers,is one of the world’s most famous tre...Compared with traditional genetic markers,genomic approaches have proved valuable to the conservation of endangered species.Paeonia ludlowii having rarely and pure yellow flowers,is one of the world’s most famous tree peonies.However,only several wild populations remain in the Yarlung Zangbo Valley(Nyingchi and Shannan regions,Xizang)in China due to increasing anthropogenic impact on the natural habitats.We used genome-wide single nucleotide polymorphisms to elucidate the spatial pattern of genetic variation,population structure and demographic history of P.ludlowii from the fragmented region comprising the entire range of this species,aiming to provide a basis for conserving the genetic resources of this species.Unlike genetic uniformity among populations revealed in previous studies,we found low but varied levels of intra-population genetic diversity,in which lower genetic diversity was detected in the population in Shannan region compared to those in Nyingzhi region.These spatial patterns may be likely associated with different population sizes caused by micro-environment differences in these two regions.Additionally,low genetic differentiation among populations(Fst=0.0037)were detected at the species level.This line of evidence,combined with the result of significant genetic differentiation between the two closest populations and lack of isolation by distance,suggested that shared ancestry among now remnant populations rather than contemporary genetic connectivity resulted in subtle population structure.Demographic inference suggested that P.ludlowii probably experienced a temporal history of sharp population decline during the period of Last Glacial Maximum,and a subsequent bottleneck event resulting from prehistoric human activities on the Qinghai-Tibet Plateau.All these events,together with current habitat fragment and excavation might contribute to the endangered status of P.ludlowii.Our study improved the genetic characterization of the endangered tree peony(P.ludlowii)in China,and these genetic inferences should be considered when making different in situ and ex situ conservation actions for P.ludlowii in this evolutionary hotspot region.展开更多
From Ligularia atroviolacea, four new eremophilendiolides, 81$-hydroxy-eremophil-3,7 （11）-dien-12,8α（14,6α）-diolide （1）, 8β-methoxy-eremophil-3,7（11）-dien-12,8α（14,6α）-diolide （2）, 8α-hydroxy-eremoph...From Ligularia atroviolacea, four new eremophilendiolides, 81$-hydroxy-eremophil-3,7 （11）-dien-12,8α（14,6α）-diolide （1）, 8β-methoxy-eremophil-3,7（11）-dien-12,8α（14,6α）-diolide （2）, 8α-hydroxy-eremophil-3,7（11）-dien-12,8lβ（14,6α）-diolide （3） and eremophil-3,7（11）,8-trien-12,8 （14,6α）-diolide （4）, as well as a known diolide （5） were isolated. Their structures were elucidated on the basis of 1D and 2D NMR as well as ESI-MS spectral data.展开更多
Emerging technologies of wireless and mobile communication enable people to accumulate a large volume of time-stamped locations,which appear in the form of a continuous moving object trajectory.How to accurately predi...Emerging technologies of wireless and mobile communication enable people to accumulate a large volume of time-stamped locations,which appear in the form of a continuous moving object trajectory.How to accurately predict the uncertain mobility of objects becomes an important and challenging problem.Existing algorithms for trajectory prediction in moving objects databases mainly focus on identifying frequent trajectory patterns,and do not take account of the effect of essential dynamic environmental factors.In this study,a general schema for predicting uncertain trajectories of moving objects with dynamic environment awareness is presented,and the key techniques in trajectory prediction arc addressed in detail.In order to accurately predict the trajectories,a trajectory prediction algorithm based on continuous time Bayesian networks（CTBNs） is improved and applied,which takes dynamic environmental factors into full consideration.Experiments conducted on synthetic trajectory data verify the effectiveness of the improved algorithm,which also guarantees the time performance as well.展开更多
Somatic cell nuclear transfer （SCNT） and parthenogenesis are alternative forms of reproduction and development, building new life cycles on differentiated somatic cell nuclei and duplicated maternal chromatin, respe...Somatic cell nuclear transfer （SCNT） and parthenogenesis are alternative forms of reproduction and development, building new life cycles on differentiated somatic cell nuclei and duplicated maternal chromatin, respectively. In the preceding paper （Sun F, et al., Cell Res 2007; 17：117-134.）, we showed that an ＂erase-and-rebuild＂ strategy is used in normal development to transform the maternal gene expression profile to a zygotic one. Here, we investigate if the same strategy also applies to SCNT and parthenogenesis. The relationship between chromatin and chromatin factors （CFs） during SCNT and parthenogenesis was examined using immunochemical and GFP-fusion protein assays. Results from these studies indicated that soon after nuclear transfer, a majority of CFs dissociated from somatic nuclei and were redistributed to the cytoplasm of the egg. The erasure process in oogenesis is recaptured during the initial phase in SCNT. Most CFs entered pseudo-pronuclei shortly after their formation. In parthenogenesis, all parthenogenotes underwent normal oogenesis, and thus had removed most CFs from chromosomes before the initiation of development. The CFs were subsequently re-associated with female pronuclei in time and sequence similar to that in fertilized embryos. Based on these data, we conclude that the ＂erase-and-rebuild＂ process observed in normal development also occurs in SCNT and in parthenogenesis, albeit in altered fashions. The process is responsible for transcription reprogramming in these procedures. The ＂erase＂ process in SCNT is compressed and the efficiency is compromised, which likely contribute to the developmental defects often observed in nuclear transfer （nt） embryos. Furthermore, results from this study indicated that the cytoplasm of an egg contains most, if not all, essential components for assembling the zygotic program and can assemble them onto appropriate diploid chromatin of distinct origins.展开更多
Natural hybridization has been regarded as a crucial pathway of speciation and provides the raw materials for the evolution of biodiversity. The interspecific natural hybridization of the genus Ligularia Cass.is unive...Natural hybridization has been regarded as a crucial pathway of speciation and provides the raw materials for the evolution of biodiversity. The interspecific natural hybridization of the genus Ligularia Cass.is universal and has been considered to be an important factor driving the high diversity of Ligularia species in the Hengduan Mountains, China. Although the natural hybridization between L. vellerea and L. subspicata was reported previously, the direction of hybridization was uncertain due to the limitation of sampling. Thus, in this study, we sampled more individuals and increased two fragments of chloroplast DNA on the basis of the previous study to further verify the natural hybridization between L. vellerea and L. subspicata and confirm the direction of hybridization. Based on DNA sequences(atpBrbcL, trnL-rpl32, trnQ-5'rps16, and nuclear ribosomal internal transcribed spacer region) data, we concluded that putative hybrids were primary products of hybridization between L. vellerea and L. subspicata and the hybridization was bidirectional. Moreover, sympatric L. tongolensis was not apparently involved in the hybridization. Surprisingly, some pure L. subspicata individuals showed the disaccordance between morphology and DNA data, which might indicate that introgression occurs between L. vellerea and L. subspicata.展开更多
基金supported by the National Nature Science Foundation of China(U21A20166)the Science and Technology Development Foundation of Jilin Province(20230508095RC)+2 种基金the Major Science and Technology Projects of Jilin Province and Changchun City(20220301033GX)the Development and Reform Commission Foundation of Jilin Province(2023C034-3)the Interdisciplinary Integration and Innovation Project of JLU(JLUXKJC2020202).
文摘Dear Editor,Aiming at the consensus tracking problem of a class of unknown heterogeneous nonlinear multiagent systems(MASs)with input constraints,a novel data-driven iterative learning consensus control(ILCC)protocol based on zeroing neural networks(ZNNs)is proposed.First,a dynamic linearization data model(DLDM)is acquired via dynamic linearization technology(DLT).
基金Supported by the Ministry of Science and Technology of the People’s Republic of China(No.2019 YFE 0125000)the National Natural Science Foundation of China-Shandong Joint Fund(No.U 1906215)+1 种基金the National Natural Science Foundation of China(No.41406010)partially by the Key Laboratory of Coastal Environmental Processes and Ecological Remediation,Chinese Academy of Sciences Opening Fund(No.2020 KFJJ 04)。
文摘As a frequently-observed phenomenon in the northern South China Sea(nSCS),subsurface chlorophyll maximum(SCM)evolution from summer to winter remains unclear,neither the associated hydrographic control.In this study,on the basis of in-situ data of fall-season cruises in 2004–2006,we characterized the depth,thickness and intensity of the SCM in the nSCS using a general Gaussian-function fitting approach,and investigated a linkage to the corresponding ocean vertical buoyance properties.Our results show that the SCM becomes deeper,thicker and less intense offshore-wards in the nSCS during fall seasons.In parallel,a correlation between the SCM variation and mixed layer depth exists in the nSCS,and it becomes pronounced in the shelf region compared to the slope and basin areas in autumn.Physically,once warmer surface ocean and thus stronger thermo-determined stratification,the SCM layer goes deeper and becomes thicker and less intense in the nSCS,especially in the shelf area of the nSCS.Moreover,the impact of water temperatures at deeper layers on the vertical stratification exerts more consequent roles on the spatial variability of SCM,compared to surface temperatures in the nSCS.Specifically,the isotherm line of 22℃ acts as crucial indicator for variations of the SCM in the nSCS during autumns.
基金Supported by the Ministry of Science and Technology of the People’s Republic of China(No.2019 YFE 0125000)the National Natural Science Foundation of China(No.42376032)。
文摘Variations in ocean mixed layer depth(MLD)show a significant impact on energy balance in the global climate systems and marine ecosystems.At present,the accuracy of modeling MLD,especially in the region with complex ocean dynamics,remains a challenge,thus calling for an emergency using artificial intelligence approach to improve the assessment of the MLD.A novel convolutional neural network model was developed based on a dual-attention module(DA-CNN)to estimate the MLD in the Bay of Bengal(BoB)by integrating multi-source remote sensing data and Argo gridded data.Compared with the original CNN model,the DA-CNN model exhibits superior performance with notable improvements in the annual average root mean square error(RMSE)and R2 values by 13.0%and 8.4%,respectively,while more accurately capturing the seasonal variations in MLD.Moreover,the results using the DA-CNN model show minimum RMSE and maximum R2 values,in comparison to the calculation by the random forest,artificial neural network model,and the hybrid coordinate ocean model.Accordingly,our findings suggest that the newly developed DA-CNN model provides an effective advantage in studying the MLD and the associated ocean processes.
基金financially supported by the National Natural Science Foundation of China,No.32002235(to MT)the Science and Technology Foundation of Taian of Shandong Province,No.2020NS216(to XL)。
文摘A growing body of evidence suggests that the gut microbiota contributes to the development of neurodegenerative diseases via the microbiota-gut-brain axis.As a contributing factor,microbiota dysbiosis always occurs in pathological changes of neurodegenerative diseases,such as Alzheimer’s disease,Parkinson’s disease,and amyotrophic lateral sclerosis.High-throughput sequencing technology has helped to reveal that the bidirectional communication between the central nervous system and the enteric nervous system is facilitated by the microbiota’s diverse microorganisms,and for both neuroimmune and neuroendocrine systems.Here,we summarize the bioinformatics analysis and wet-biology validation for the gut metagenomics in neurodegenerative diseases,with an emphasis on multi-omics studies and the gut virome.The pathogen-associated signaling biomarkers for identifying brain disorders and potential therapeutic targets are also elucidated.Finally,we discuss the role of diet,prebiotics,probiotics,postbiotics and exercise interventions in remodeling the microbiome and reducing the symptoms of neurodegenerative diseases.
基金This work was supported by the National Key R&D Program of China(2017YF0505200).The authors thank Fangming Zhang for her assistance with plant sampling,and Xiuyan Feng,Rui Yang and Yujuan Zhao for their help and discussion of data analyses.
文摘Cycas panzhihuaensis L.Zhou & S.Y.Yang(Cycadaceae) is an endangered gymnosperm species endemic to the dry-hot valley of the Jinsha River basin in southwest China.Although the wild C.panzhihuaensis population from Panzhihua Cycad Natural Reserve is well protected and its genetic diversity has been well assessed,the genetic characteristics of populations outside the nature reserve,which face larger risks of extinction,remain unknown.Furthermore,the population genetics and historical dynamics of this endemic and endangered species have not been examined across its entire range.In this study,to analyze the genetic diversity,phylogeographical structure and demographic history of C.panzhihuaensis from all its seven known locations,we sequenced and compared molecular data from chloroplastic DNA(psbA-trnH,psbM-trnD,and trnS-trnG),single-copy nuclear genes(PHYP,AC5,HSP70,and AAT) from 61 individuals,as well as 11 nuclear micro satellite loci(SSR) from 102 individuals.We found relatively high genetic diversity within populations and high genetic differentiation among populations of C.panzhihuaensis,which is consistent with the patterns of other Asian inland cycads.Although no significant phylogeographical structure was detected,we found that small and unprotected populations possess higher genetic diversity and more unique haplotypes,which revises our understanding of diversity within this species and deserves due attention.Analysis of demographic dynamics suggest that human activity might be the key threat to C.panzhihuaensis.Based on the genetic characterization of C.panzhihuaensis,we propose several practical guidelines for the conservation of this species,especially for the populations with small sizes.
基金supported by the Natural Science Foundation of Yunnan Province,as well as by a grant from the Technology Foundation and the National Key Project for Basic Research(973no.2007CB411600).
文摘Genera Lamiophlomis and Paraphlomis were originally separated from genus Phlomis s.1. on the basis of particular morphological characteristics. However, their relationship was highly contentious, as evidenced by the literature. In the present paper, the systematic positions of Lamiophlomis, Paraphlomis, and their related genera were assessed based on nuclear internal transcribed spacer （ITS） and chloroplast rpl16 and trnL-F sequence data using maximum parsimony （MP） and Bayesian methods. and outgroup were sampled. Analyses of both separate In total, 24 species representing six genera of the ingroup and combined sequence data were conducted to resolve the systematic relationships of these genera. The results reveal that Lamiophlomis is nested within Phlomis sect. Phlomoides and its generic status is not supported. With the inclusion ofLamiophlomis rotata in sect. Phlomoides, sections Phlomis and Phlomoides of Phlomis were resolved as monophyletic. Paraphlomis was supported as an independent genus. However, the resolution of its monophyly conflicted between MP and Bayesian analyses, suggesting the need for expended sampling and further evidence.
基金the National Key R&D Program of China(No.2019YFC1711000)the National Natural Science Foundation(No.31600171)+1 种基金the Shenzhen Urban Management Bureau Fund(No.201520)the Shenzhen Municipal Government of China(No.JCYJ20170817145512467)。
文摘Magnolia biondii Pamp.(Magnoliaceae,magnoliids)is a phylogenetically,economically,and medicinally important ornamental tree species widely grown and cultivated in the north-temperate regions of China.Determining the genome sequence of M.biondii would help resolve the phylogenetic uncertainty of magnoliids and improve the understanding of individual trait evolution within the Magnolia genus.We assembled a chromosome-level reference genome of M.biondii using~67,~175,and~154Gb of raw DNA sequences generated via Pacific Biosciences single-molecule real-time sequencing,10X Genomics Chromium,and Hi-C scaffolding strategies,respectively.The final genome assembly was~2.22Gb,with a contig N50 value of 269.11 kb and a BUSCO complete gene percentage of 91.90%.Approximately 89.17%of the genome was organized into 19 chromosomes,resulting in a scaffold N50 of 92.86Mb.The genome contained 47,547 protein-coding genes,accounting for 23.47%of the genome length,whereas 66.48%of the genome length consisted of repetitive elements.We confirmed a WGD event that occurred very close to the time of the split between the Magnoliales and Laurales.Functional enrichment of the Magnolia-specific and expanded gene families highlighted genes involved in the biosynthesis of secondary metabolites,plant–pathogen interactions,and responses to stimuli,which may improve the ecological fitness and biological adaptability of the lineage.Phylogenomic analyses revealed a sister relationship of magnoliids and Chloranthaceae,which are sister to a clade comprising monocots and eudicots.The genome sequence of M.biondii could lead to trait improvement,germplasm conservation,and evolutionary studies on the rapid radiation of early angiosperms.
基金This work was financially supported by the National Basic Research Program of China(973 Program No.2009CB522303 and No.2011CB915503)the NSFC(No.U0932602)+1 种基金the National Natural Science Foundation of China(No.90813004)the State Key Laboratory of Phytochemistry and Plant Resources in West China(No.P2010-ZZ05).
文摘Phytochemical investigation of the aerial parts of the monotypic plant,Musella lasiocarpa,led to the isolation of four rare bicyclic diarylheptanoids,musellarins B-E(2-5),two new phenylphenalenones,2-methoxy-9-(3′,4′-dihydroxyphenyl)-1H-phenalen-1-one(9),2-methoxy-9-(3′-methoxy-4′-hydroxyphenyl)-1H-phenalen-1-one(10),a new acenaphtylene derivative,trans-(1S,2S)-3-(4′-methoxyphenyl)-acenaphthene-1,2-diol(13),and two new sucrose esters,1,2′,3′,4′,6′-O-pentaacetyl-3-O-trans-p-coumaroylsucrose(16),1,2′,3′,4′,6′-O-pentaacetyl-3-O-cis-p-coumaroylsucrose(17),together with nine known compounds.In addition,(4E,6E)-1-(3′,4′-dihydroxyphenyl)-7-(4′′-hydroxyphenyl)-hepta-4,6-dien-3-one(15)was isolated for the first time from a natural source.The structures of new compounds were elucidated by analysis of their spectroscopic data.Compounds 2,6,8-10,12,and 14 were cytotoxic toward several of the human tumor cell lines(HL-60,SMMC-7721,A-549,MCF-7,and SW480).Of these,the new compound 9 was the most potent one,with IC50 values of 5.8,10.3,6.3,3.3,and 2.3μM,respectively.
基金supported by the United Fund of the NSFCthe Yunnan Natural Science Foundation(Grant No.U1136602 to X.G.)
文摘Geological activities and climate oscillations during the Quaternary period profoundly impacted the distribution of species in Southwest China. Some plant species may be harbored in refugia, such as the dry-hot valleys of Southwest China. Cycas chenii X. Gong & W. Zhou, a critically endangered cycad species, which grows under the canopy in subtropical evergreen broad-leaved forests along the upstream drainage area of the Red River, is endemic to this refugium. In this study, 60 individuals of C. chenii collected from six populations were analyzed by sequencing two chloroplast intergenic spacers(cp DNA:psb A-trn H and trn L-trn F) and two nuclear genes(PHYP and RBP-1). Results showed high genetic diversity at the species level, but low within-population genetic diversity and high interpopulation genetic differentiation. A Bayesian phylogenetic tree based on cp DNA showed that five chloroplast haplotypes were clustered into two clades, which corresponds to the division of the western and eastern bank of the Red River. These data indicate a possible role for the Red River as a geographic barrier to gene flow in C. chenii.Based on our findings, we propose appropriate in situ and ex situ conservation strategies for C. chenii.
基金supported by grants from the NationalScience & Technology Pillar Program of China duringthe Twelfth Five-year Plan Period (No. 2014BAI05B05)the National Natural Science Foundation of China (No.81873843)the Foundation at Research Funds forthe Central Universities (No. 2017kfyXJJ102 and No.2019kfyXKJC053).
文摘Placenta accreta spectrum disorder (PASD) and placenta previa (PP) are two of the mosthideous obstetric complications which are usually associated with a history of cesarean section(CS). Moreover, women with PASD, PP and/or a cesarean scarred uterus are more likely to haveadverse pregnancy outcomes, including blood transfusion, hysterectomy, pelvic organs damage,postpartum hemorhage, disseminated intravascular coagulation, multi-organ dysfunction syndromeand even maternal or fetal death. This study aimed to investigate the efficacy of precesareaninternal iliac artery balloon catheterization (BC) for managing severe hemorhage caused by PASDand PP with a history of CS. This participant-assigned interventional study was conducted inTongji Hospital. We recruited 128 women with suspected PASD, PP and a history of CS. Womenin the BC group accepted precesarean BC of bilateral internal iliac arteries before the scheduledcesarean delivery. Women in the control group underwent a conventional cesarean delivery.Intraoperative hemorrhage, transfusion volume, radiation dose, exposure time, complicationsand neonatal outcomes were discussed. There were significant differences in calculated bloodloss (CBL) between BC group and control group (1015.0±144.9 vs. 1467.0±171.0 mL, P=0.04).Precesarean BC could reduce intraoperative red blood cell (RBC) transfusion as compared withcontrol group (799.5±136.1 vs. 1286.0±161.6 mL, P=0.02) and lessen the rate of using bloodproducts (57.1% vs. 76.4%, P=0.02). The incidence of hysterectomy was also lower in BC groupthan in control group. Postpartum outcomes showed no significant differences between the twogroups, except that postoperation hospitalization was longer in BC group than in control group(6.7±0.4 vs. 5.8±0.2 days, P=0.03). Precesarean BC of internal iliac artery is an effective methodfor managing severe hemorrhage caused by PASD and PP with a cesarean scarred uterus, as it couldreduce intraoperative blood loss, lessen intraoperative RBC transfusions and potentially decreasehysterectomies.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research(STEP)Program(2019QZKK0502)the National Natural Science Foundation of China(NSFC,31400324)+1 种基金Independent research project of Yunnan Provincial Key Laboratory of Wild Resources Plant Research(E03K581261)National Key Research Development Program of China(2022YFC2601200)。
文摘Compared with traditional genetic markers,genomic approaches have proved valuable to the conservation of endangered species.Paeonia ludlowii having rarely and pure yellow flowers,is one of the world’s most famous tree peonies.However,only several wild populations remain in the Yarlung Zangbo Valley(Nyingchi and Shannan regions,Xizang)in China due to increasing anthropogenic impact on the natural habitats.We used genome-wide single nucleotide polymorphisms to elucidate the spatial pattern of genetic variation,population structure and demographic history of P.ludlowii from the fragmented region comprising the entire range of this species,aiming to provide a basis for conserving the genetic resources of this species.Unlike genetic uniformity among populations revealed in previous studies,we found low but varied levels of intra-population genetic diversity,in which lower genetic diversity was detected in the population in Shannan region compared to those in Nyingzhi region.These spatial patterns may be likely associated with different population sizes caused by micro-environment differences in these two regions.Additionally,low genetic differentiation among populations(Fst=0.0037)were detected at the species level.This line of evidence,combined with the result of significant genetic differentiation between the two closest populations and lack of isolation by distance,suggested that shared ancestry among now remnant populations rather than contemporary genetic connectivity resulted in subtle population structure.Demographic inference suggested that P.ludlowii probably experienced a temporal history of sharp population decline during the period of Last Glacial Maximum,and a subsequent bottleneck event resulting from prehistoric human activities on the Qinghai-Tibet Plateau.All these events,together with current habitat fragment and excavation might contribute to the endangered status of P.ludlowii.Our study improved the genetic characterization of the endangered tree peony(P.ludlowii)in China,and these genetic inferences should be considered when making different in situ and ex situ conservation actions for P.ludlowii in this evolutionary hotspot region.
文摘From Ligularia atroviolacea, four new eremophilendiolides, 81$-hydroxy-eremophil-3,7 （11）-dien-12,8α（14,6α）-diolide （1）, 8β-methoxy-eremophil-3,7（11）-dien-12,8α（14,6α）-diolide （2）, 8α-hydroxy-eremophil-3,7（11）-dien-12,8lβ（14,6α）-diolide （3） and eremophil-3,7（11）,8-trien-12,8 （14,6α）-diolide （4）, as well as a known diolide （5） were isolated. Their structures were elucidated on the basis of 1D and 2D NMR as well as ESI-MS spectral data.
基金supported by the National Natural Science Foundation of China (Nos.61100045,61165013,61003142,60902023,and 61171096)the China Postdoctoral Science Foundation (Nos.20090461346,201104697)+3 种基金the Youth Foundation for Humanities and Social Sciences of Ministry of Education of China (No.10YJCZH117)the Fundamental Research Funds for the Central Universities (Nos.SWJTU09CX035,SWJTU11ZT08)Zhejiang Provincial Natural Science Foundation of China (Nos.Y1100589,Y1080123)the Natural Science Foundation of Ningbo,China (No.2011A610175)
文摘Emerging technologies of wireless and mobile communication enable people to accumulate a large volume of time-stamped locations,which appear in the form of a continuous moving object trajectory.How to accurately predict the uncertain mobility of objects becomes an important and challenging problem.Existing algorithms for trajectory prediction in moving objects databases mainly focus on identifying frequent trajectory patterns,and do not take account of the effect of essential dynamic environmental factors.In this study,a general schema for predicting uncertain trajectories of moving objects with dynamic environment awareness is presented,and the key techniques in trajectory prediction arc addressed in detail.In order to accurately predict the trajectories,a trajectory prediction algorithm based on continuous time Bayesian networks（CTBNs） is improved and applied,which takes dynamic environmental factors into full consideration.Experiments conducted on synthetic trajectory data verify the effectiveness of the improved algorithm,which also guarantees the time performance as well.
文摘Somatic cell nuclear transfer （SCNT） and parthenogenesis are alternative forms of reproduction and development, building new life cycles on differentiated somatic cell nuclei and duplicated maternal chromatin, respectively. In the preceding paper （Sun F, et al., Cell Res 2007; 17：117-134.）, we showed that an ＂erase-and-rebuild＂ strategy is used in normal development to transform the maternal gene expression profile to a zygotic one. Here, we investigate if the same strategy also applies to SCNT and parthenogenesis. The relationship between chromatin and chromatin factors （CFs） during SCNT and parthenogenesis was examined using immunochemical and GFP-fusion protein assays. Results from these studies indicated that soon after nuclear transfer, a majority of CFs dissociated from somatic nuclei and were redistributed to the cytoplasm of the egg. The erasure process in oogenesis is recaptured during the initial phase in SCNT. Most CFs entered pseudo-pronuclei shortly after their formation. In parthenogenesis, all parthenogenotes underwent normal oogenesis, and thus had removed most CFs from chromosomes before the initiation of development. The CFs were subsequently re-associated with female pronuclei in time and sequence similar to that in fertilized embryos. Based on these data, we conclude that the ＂erase-and-rebuild＂ process observed in normal development also occurs in SCNT and in parthenogenesis, albeit in altered fashions. The process is responsible for transcription reprogramming in these procedures. The ＂erase＂ process in SCNT is compressed and the efficiency is compromised, which likely contribute to the developmental defects often observed in nuclear transfer （nt） embryos. Furthermore, results from this study indicated that the cytoplasm of an egg contains most, if not all, essential components for assembling the zygotic program and can assemble them onto appropriate diploid chromatin of distinct origins.
基金supported by the National Science Foundation of China (31470336 to XG)
文摘Natural hybridization has been regarded as a crucial pathway of speciation and provides the raw materials for the evolution of biodiversity. The interspecific natural hybridization of the genus Ligularia Cass.is universal and has been considered to be an important factor driving the high diversity of Ligularia species in the Hengduan Mountains, China. Although the natural hybridization between L. vellerea and L. subspicata was reported previously, the direction of hybridization was uncertain due to the limitation of sampling. Thus, in this study, we sampled more individuals and increased two fragments of chloroplast DNA on the basis of the previous study to further verify the natural hybridization between L. vellerea and L. subspicata and confirm the direction of hybridization. Based on DNA sequences(atpBrbcL, trnL-rpl32, trnQ-5'rps16, and nuclear ribosomal internal transcribed spacer region) data, we concluded that putative hybrids were primary products of hybridization between L. vellerea and L. subspicata and the hybridization was bidirectional. Moreover, sympatric L. tongolensis was not apparently involved in the hybridization. Surprisingly, some pure L. subspicata individuals showed the disaccordance between morphology and DNA data, which might indicate that introgression occurs between L. vellerea and L. subspicata.
