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Species’ geographical range, environmental range and traits lead to specimen collection preference of dominant plant species of grasslands in Northern China

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Plant Diversity 2024年第3期46卷 353-361页

作者： Jingya Zhang Cui Xiao Xiaoyu Duan xin gao Hao Zeng Rong'an Dong Gang Feng Keping Ma Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau&Inner Mongolia Key Laboratory of Grassland Ecology School of Ecology and EnvironmentInner Mongolia UniversityHohhot 010021China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection in China is preferred by species traits(i.e.,plant height,flowering and fruiting period),environmental range(i.e.,the temperature and precipitation range)and geographical range(i.e.,distribution range and altitudinal range).Ordinary least squares models and phylogenetic generalized linear mixed models were used to analyze the relationships between specimen number and the explanatory variables.Random Forest models were then used to find the most parsimonious multivariate model.The results showed that interannual variation in specimen number between 1900 and 2020 was considerable.Specimen number of these species in southeast China was notably lower than that in northwest China.Environmental range and geographical range of species had significant positive correlations with specimen number.In addition,there were relatively weak but significant associations between specimen number and species trait(i.e.,plant height and flowering and fruiting period).Random Forest models indicated that distribution range was the most important variable,followed by flowering and fruiting period,and altitudinal range.These findings suggest that future floristic surveys should pay more attention to species with small geographical range,narrow environmental range,short plant height,and short flowering and fruiting period.The correction of specimen collection preference will also make the results of species distribution model,species evolution and other works based on specimen data more accurate.

关键词： Biological specimen Collection preference Dominant plant species Environmental range Geographical range Species traits

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Identification and characterization of human hematopoietic mesoderm

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Science China(Life Sciences) 2024年第2期67卷 320-331页

作者： Yuqi Wen Jingjing Zhao Runqing Zhang Fan Liu Xiaoyuan Chen Dan Wu Mengge Wang Cuicui Liu Pei Su Panpan Meng Yiyue Zhang xin gao Lu Wang Hongtao Wang Jiaxi Zhou State Key Laboratory of Experimental Hematology National Clinical Research Center for Blood DiseasesHaihe Laboratory of Cell EcosystemInstitute of Hematology&Blood Diseases HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeTianjin 300020China Tianjin Institutes of Health Science Tianjin 301600China CAMS Center for Stem Cell Medicine PUMC Department of Stem Cell and Regenerative MedicineTianjin 300020China Division of Cell Developmental and Integrative BiologySchool of MedicineSouth China University of TechnologyGuangzhou 510006China

The embryonic mesoderm comprises heterogeneous cell subpopulations with distinct lineage biases.It is unclear whether a bias for the human hematopoietic lineage emerges at this early developmental stage.In this study,we integrated single-cell transcriptomic analyses of human mesoderm cells from embryonic stem cells and embryos,enabling us to identify and define the molecular features of human hematopoietic mesoderm(HM)cells biased towards hematopoietic lineages.We discovered that BMP4 plays an essential role in HM specification and can serve as a marker for HM cells.Mechanistically,BMP4 acts as a downstream target of HDAC1,which modulates the expression of BMP4 by deacetylating its enhancer.Inhibition of HDAC significantly enhances HM specification and promotes subsequent hematopoietic cell differentiation.In conclusion,our study identifies human HM cells and describes new mechanisms for human hematopoietic development.

关键词： hematopoietic mesoderm human pluripotent stem cells human embryos BMP4 HDAC1

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Deciphering the population structure and genetic basis of growth traits from whole-genome resequencing of the leopard coral grouper(Plectropomus leopardus)

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Zoological Research 2024年第2期45卷 329-340页

作者： Shao-Xuan Wu Qi-Fan Zeng Wen-Tao Han Meng-Ya Wang Hui Ding Ming-Xuan Teng Ming-Yi Wang Pei-Yu Li xin gao Zhen-Min Bao Bo Wang Jing-Jie Hu MOE Key Laboratory of Marine Genetics and Breeding College of Marine Life Sciences/Key Laboratory of Tropical Aquatic Germplasm of Hainan ProvinceSanya Oceanographic InstitutionOcean University of ChinaQingdaoShandong/SanyaHainan 266100/572025China Hainan Seed Industry Laboratory SanyaHainan 572025China Southern Marine Science and Engineer Guangdong Laboratory GuangzhouGuangdong 511458China

The leopard coral grouper(Plectropomus leopardus)is a species of significant economic importance.Although artificial cultivation of P.leopardus has thrived in recent decades,the advancement of selective breeding has been hindered by the lack of comprehensive population genomic data.In this study,we identified over 8.73 million single nucleotide polymorphisms(SNPs)through whole-genome resequencing of 326 individuals spanning six distinct groups.Furthermore,we categorized 226 individuals with high-coverage sequencing depth(≥14×)into eight clusters based on their genetic profiles and phylogenetic relationships.Notably,four of these clusters exhibited pronounced genetic differentiation compared with the other populations.To identify potentially advantageous loci for P.leopardus,we examined genomic regions exhibiting selective sweeps by analyzing the nucleotide diversity(θπ)and fixation index(FST)in these four clusters.Using these high-coverage resequencing data,we successfully constructed the first haplotype reference panel specific to P.leopardus.This achievement holds promise for enabling high-quality,cost-effectiveimputationmethods.Additionally,we combined low-coverage sequencing data with imputation techniques for a genome-wide association study,aiming to identify candidate SNP loci and genes associated with growth traits.A significant concentration of these genes was observed on chromosome 17,which is primarily involved in skeletal muscle and embryonic development and cell proliferation.Notably,our detailed investigation of growth-related SNPs across the eight clusters revealed that cluster 5 harbored the most promising candidate SNPs,showing potential for genetic selective breeding efforts.These findings provide a robust toolkit and valuable insights into the management of germplasm resources and genome-driven breeding initiatives targeting P.leopardus.

关键词： Plectropomus leopardus Whole-genome resequencing Growth Haplotype reference panel Single nucleotide polymorphisms

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Calycosin improves atherosclerosis by reshaping the interaction between the gut microbiome and bile acid metabolism

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Food Science and Human Wellness 2024年

作者： Jiaqi Fu Donghua Yu Yuqin Liang xin gao Yunhe Shi Yu Wang Pingping Chen Shumin Liu Fang Lu Institute of Traditional Chinese Medicine Heilongjiang University of Chinese Medicine

Calycosin， Astragali Radix most prominent ingredient， has drawn more attention as a result of its ability to treat atherosclerosis(AS). However， the mechanism of action has not been fully elucidated. We investigated the effects of calycosin on bile acid (BA) metabolism and gut microbiome in ApoE-/-mice fed a high-fat diet (HFD). The data showed that the aorta of ApoE-/-mice treated with HFD showed significant atheromatous plaque formation and lipid accumulation， and the levels of TC， TG and LDL-C were significantly increased， while the levels of HDL-C were significantly decreased. Calycosin can substantially regulate lipid levels， thereby alleviating liver lipid deposition induced by atherosclerosis. In addition， 16S rRNA sequencing showed that calycosin treatment has reshaped the gut microbiota disturbed by HFD， in particular， increasing the ratio of Bacteroidetes/Firmicutes， and improving the relative abundance of Bilophila， Desulfovibrio， Bacteroides， Lactobacillus， etc. Meanwhile， targeted metabolomics analysis showed that calycosin treatment significantly modulated CDCA， TCA， LCA， DCA， TDCA and bile acid pool composition， which were associated with atherosclerotic plaque areas. In addition， calycosin treatment also down-regulated FXR protein levels and up-regulated CYP7A1 protein levels in the hepatic. At the same time， calycosin inhibits the ileum FXR/TGR5 signaling pathway， inhibits BA reabsorption， promotes BA excretion， and reduces hepatic cholesterol accumulation by enterohepatic circulation. In addition， we found that calycosin significantly promoted the expression of hepatic ABCA1 and ABCG1 to mediate cholesterol efflux. Meanwhile， calycosin regulates gut microbiota， and Bacteroides， Alistipes， Desulfovibrio， Lactobacillus， Bilophila and Odoribacter are closely related to specific BAs. This enables us to further understand the relationship between BA metabolism and gut microbiota. Calycosin may reduce high-fat diet-induced hepatic cholesterol accumulation in ApoE-/-mice through gut microbiota and bile

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Love wave propagation in one-dimensional piezoelectric quasicrystal multilayered nanoplates with surface effects

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 619-632页

作者： xin FENG Liaoliang KE Yang gao College of Science China Agricultural UniversityBeijing 100083China School of Mechanical Engineering Tianjin UniversityTianjin 300350China

The exact solutions for the propagation of Love waves in one-dimensional(1D)hexagonal piezoelectric quasicrystal(PQC)nanoplates with surface effects are derived.An electro-elastic model is developed to investigate the anti-plane strain problem of Love wave propagation.By introducing three shape functions,the wave equations and electric balance equations are decoupled into three uncorrelated problems.Satisfying the boundary conditions of the top surface on the covering layer,the interlayer interface,and the matrix,a dispersive equation with the influence of multi-physical field coupling is provided.A surface PQC model is developed to investigate the surface effects on the propagation behaviors of Love waves in quasicrystal(QC)multilayered structures with nanoscale thicknesses.A novel dispersion relation for the PQC structure is derived in an explicit closed form according to the non-classical mechanical and electric boundary conditions.Numerical examples are given to reveal the effects of the boundary conditions,stacking sequence,characteristic scale,and phason fluctuation characteristics on the dispersion curves of Love waves propagating in PQC nanoplates with surface effects.

关键词： piezoelectric quasicrystal(PQC)material multilayered plate dispersion characteristic surface effect

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Genomic surveillance of emerging SARS-CoV-2 Omicron variations in Tianjin Municipality, China 2022

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Biosafety and Health 2024年第2期6卷 61-69页

作者： xin gao Ming Zou Yue Lei Zhaolin Tan Zhichao Zhuang Baolu Zheng Aiping Yu Yanzhen Han Xiaohui Lu Xiaochang Liu Ying Wang Yuan Wang Liru Guo Guangwen Liu Wen Li Yang Liu Likun Lv Peiyong Ning Xiaoyan Li Tianjin Centers for Disease Control and Prevention Tianjin 300011China Tianjin Key Laboratory of Pathogenic Microbiologyof Infectious Disease Tianjn Centers for Disease Controland PreventionTianjin 300011China

The coronavirus disease 2019(COvID-19)pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has severely impacted public health.In 2022,the Omicron variant of SARS-CoV-2 rapidly became the dominant circulating variant in the local COVID-19 outbreaks in Tianjin Municipality,China.To gain a deeper understanding of the genetic variations of the Omicron variant in Tianjin,specimens from indi-viduals who tested positive for SARS-CoV-2 between December 2021 and November 2022 were used for virus whole genome sequencing and phylogenetic analysis.A total of 1,674 high-quality Omicron sequences were obtained,consisting of 1,339 sequences from local cases belonging to 20 Phylogenetic Assignment of Named Global Outbreak(PANGO)lineages and 335 sequences from imported cases belonging to 70 lineages.Tianjin experienced five waves of local outbreaks,accompanied by multiple substitutions among subvariants,ranging from the initial BA.1.1 lineage to the subsequent BA.2,BF.7,and BA.5.2 lineages.The evolutionary rate of local strains,estimated to be 28.999 substitutions per year,and the evolutionary rate of imported strains,estimated to be 24.946 substitutions per year,were lower than that of the strains circulating globally.The addi-tional substitutions and deletions of local strains have been used to identify and disrupt the virus transmission chains.The subvariants such as BA.5.2.48,BA.5.2.49,BF.7.14,and XBB.1 circulating in the fifth epidemic wave presented criterial immune escape mutations including S:R346T,S:L452R and S:F486V.It is essential to implement genomic surveillance strategies to investigate further the development of genomic mutation char-acteristics in the SARS-CoV-2 variant.This ongoing monitoring will contribute to a better understanding of the virus's genetic changes and aid in effective control measures.

关键词： Severeacute respiratory syndrome coronavirus 2(SARS-CoV-2) Coronavirusdisease2019(COVID-19) Omicron variant Wholegenome sequencing(WGS)

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Microstructure evolution and strengthening mechanism of high -performance powder metallurgy TA15 titanium alloy by hot rolling

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1426-1436页

作者： Ying gao Ce Zhang Jiazhen Zhang xin Lu Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsInstitute for Advanced Ma-terials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China National Engineering Research Center for Advanced Rolling Technology National Engineering Research Center for Flat Rolling EquipmentInstitute of Engin-eering TechnologyUniversity of Science and Technology BeijingBeijing 100083China

Hot deformation of sintered billets by powder metallurgy(PM)is an effective preparation technique for titanium alloys,which is more significant for high-alloying alloys.In this study,Ti–6.5Al–2Zr–Mo–V(TA15)titanium alloy plates were prepared by cold press-ing sintering combined with high-temperature hot rolling.The microstructure and mechanical properties under different process paramet-ers were investigated.Optical microscope,electron backscatter diffraction,and others were applied to characterize the microstructure evolution and mechanical properties strengthening mechanism.The results showed that the chemical compositions were uniformly dif-fused without segregation during sintering,and the closing of the matrix craters was accelerated by increasing the sintering temperature.The block was hot rolled at 1200℃ with an 80%reduction under only two passes without annealing.The strength and elongation of the plate at 20–25℃ after solution and aging were 1247 MPa and 14.0%,respectively,which were increased by 24.5%and 40.0%,respect-ively,compared with the as-sintered alloy at 1300℃.The microstructure was significantly refined by continuous dynamic recrystalliza-tion,which was completed by the rotation and dislocation absorption of the substructure surrounded by low-angle grain boundaries.After hot rolling combined with heat treatment,the strength and plasticity of PM-TA15 were significantly improved,which resulted from the dense,uniform,and fine recrystallization structure and the synergistic effect of multiple slip systems.

关键词： elemental powder powder metallurgy titanium alloy hot rolling strength and plasticity

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Flow Field Simulation and Parameter Analysis of Hydraulic Unbalanced Bionic Self-recovery Actuator for Rotary Equipment

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Journal of Bionic Engineering 2024年第1期21卷 325-343页

作者： Wei Li xin Pan Dehong Ge Jinji gao Key Laboratory of Engine Health Monitoring-Control and Networking of Ministry of Education Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of High-End Mechanical Equipment Health Monitoring and Self-Recovery Beijing University of Chemical TechnologyBeijing 100029China

The rotor is the most important component of rotating machinery,and the vibration produced by its mass unbalance has a serious influence on the secure and steady operation of the machine,so an effective online suppression technology is urgently needed.A new hydraulic unbalanced bionic self-recovery system is introduced,imitating the way of manually repairing faulty equipment.To accomplish the effect of actuator mass redistribution,the technology employs pressurized air to drive the quantitative transfer of liquid in the reservoir cavity at opposite positions.It can complete the online adjustment of the equipment's balancing state and suppress the unbalanced vibration of equipment in real time,which gives the equipment the ability to maintain an autonomous health state and improve equipment performance.The composition and working principle of the system are introduced in detail,and the key performance parameters,such as the minimum running speed and the balancing liquid transfer speed,are analyzed theoretically.The fluid-solid coupling model of the actuator was established,and the two-phase flow from inside the hydraulic unbalanced bionic self-recovery actuator was simulated under multiple working conditions and the performance parameters were quantitatively analyzed.A balancing simulation test bed was built,and its effectiveness was verified by performance parameter tests and unbalanced bionic self-recovery experiments.The experimental results show that the mass distribution adjustment of the balancing disk can be achieved using different viscosity balancing liquid,and the response of liquid viscosity 10 cSt is faster than that of liquid viscosity 100 cSt in the process of balancing liquid transfer,and the time is reduced by more than 75%;the system can reduce the simulated rotor amplitude from 18.3μm to 10.6μm online in real time,which provides technical support for the subsequent development of a new generation of bionic intelligent equipment.

关键词： Engineering self-recovery-Bionics Simulation analysis Self-recovery regulation

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Knowledge Graph Enhanced Transformers for Diagnosis Generation of Chinese Medicine

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Chinese Journal of Integrative Medicine 2024年第3期30卷 267-276页

作者： WANG xin-yu YANG Tao gao Xiao-yuan HU Kong-fa School of Artificial Intelligence and Information Technology Nanjing University of Chinese MedicineNanjing210023China School of Information Management Nanjing UniversityNanjing210023China Jiangsu Collaborative Innovation Center of Traditional Chinese Medicine in Prevention and Treatment of Tumor Nanjing210023China Jiangsu Province Engineering Research Center of TCM Intelligence Health Service Nanjing210023China

Chinese medicine(CM)diagnosis intellectualization is one of the hotspots in the research of CM modernization.The traditional CM intelligent diagnosis models transform the CM diagnosis issues into classification issues,however,it is difficult to solve the problems such as excessive or similar categories.With the development of natural language processing techniques,text generation technique has become increasingly mature.In this study,we aimed to establish the CM diagnosis generation model by transforming the CM diagnosis issues into text generation issues.The semantic context characteristic learning capacity was enhanced referring to Bidirectional Long Short-Term Memory(BILSTM)with Transformer as the backbone network.Meanwhile,the CM diagnosis generation model Knowledge Graph Enhanced Transformer(KGET)was established by introducing the knowledge in medical field to enhance the inferential capability.The KGET model was established based on 566 CM case texts,and was compared with the classic text generation models including Long Short-Term Memory sequence-to-sequence(LSTM-seq2seq),Bidirectional and Auto-Regression Transformer(BART),and Chinese Pre-trained Unbalanced Transformer(CPT),so as to analyze the model manifestations.Finally,the ablation experiments were performed to explore the influence of the optimized part on the KGET model.The results of Bilingual Evaluation Understudy(BLEU),Recall-Oriented Understudy for Gisting Evaluation 1(ROUGE1),ROUGE2 and Edit distance of KGET model were 45.85,73.93,54.59 and 7.12,respectively in this study.Compared with LSTM-seq2seq,BART and CPT models,the KGET model was higher in BLEU,ROUGE1 and ROUGE2 by 6.00–17.09,1.65–9.39 and 0.51–17.62,respectively,and lower in Edit distance by 0.47–3.21.The ablation experiment results revealed that introduction of BILSTM model and prior knowledge could significantly increase the model performance.Additionally,the manual assessment indicated that the CM diagnosis results of the KGET model used in this study were highly consistent with the p

关键词： Chinese medicine diagnosis knowledge graph enhanced transformer text generation

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Research on ozone formation sensitivity based on observational methods:Development history,methodology,and application and prospects in China

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Journal of Environmental Sciences 2024年第4期138卷 543-560页

作者： Wanghui Chu Hong Li Yuanyuan Ji xin Zhang Likun Xue Jian gao Cong An State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Environment Research Institute Shandong UniversityQingdao 266237China

Observation-based method for O_(3)formation sensitivity research is an important tool to analyze the causes of ground-level O_(3)pollution,which has broad application potentials in determining the O_(3)pollution formation mechanism and developing prevention and control strategies.This paper outlined the development history of research on O_(3)formation sensitivity based on observational methods,described the principle and applicability of the methodology,summarized the relative application results in China and provided recommendations on the prevention and control of O_(3)pollution in China based on relevant study results,and finally pointed out the shortcomings and future development prospects in this field in China.The overview study showed that the O_(3)formation sensitivity in some urban areas in China in recent years presented a gradual shifting tendency from the VOC-limited regime to the transition regime or the NO_(x)-limited regime due to the implementation of the O_(3)precursors emission reduction policies;O_(3)pollution control strategies and precursor control countermeasures should be formulated based on local conditions and the dynamic control capability of O_(3)pollution control measures should be improved.There are still some current deficiencies in the study field in China.Therefore,it is recommended that a stereoscopic monitoring network for atmospheric photochemical components should be further constructed and improved;the atmospheric chemical mechanisms should be vigorously developed,and standardized methods for determining the O_(3)formation sensitivity should be established in China in the near future.

关键词： Observation-based method Ozone formation sensitivity Ozone pollution prevention and control VOCs NO_(x) OBM

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