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Surface pollen and modern veg.tation in Southern Xinjiang.China

Science China Earth Sciences 2024年第2期67卷 510-530页

作者： Yun ZHANg.Lixin CHEN Yaoyao XI Zhaochen kong Xiang.o qiao State Key Laboratory of Black Soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun130102China Institute of Botany Chinese Academy of SciencesBeijing100093China Key Laboratory of Cenozoic g.olog. and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China University of Chinese Academy of Sciences Beijing100049China School of g.osciences and Resources China University of Geosciences(Beijing)Beijing100083China

The study of modern pollen,and veg.tation can improve the accuracy of paleoenvironmental reconstruction based on fossil pollen data.A total of 188 pollen surface samples were collected from Southern Xinjiang.34°00’–43°00’N,74°00’–94°00’E)in China,with an elevation rang. of 888–4530 *** pollen and veg.tation were studied in the northern reg.on of the Kunlun Mountains and the southern reg.on of the Tianshan *** results showed that the surface pollen assemblag.s on the southern slope of the Tianshan Mountains(3530–1124 m)were divided into three pollen zones,namely,montane steppe,montane desert steppe,and montane *** zones were dominated by Artemisia,Chenopodiaceae,and Ephedra *** surface pollen assemblag.s in the eastern Pamir Plateau(4530–1287 m)could be divided into alpine meadow,montane desert steppe,and montane desert zones,which were predominantly characterized by Artemisia,Chenopodiaceae,and Asteraceae ***,the Southern Tarim Basin(3548–888 m)comprised montane desert steppe and montane desert zones,which was dominated by Artemisia and Chenopodiaceae *** g.og.aphic distribution of the surface pollen sites obtained using.Arcg.S,the R-value,and Pearson correlation analyses indicated that the over-represented Picea and Pinus pollen were of external orig.n and were transported by wind,water(rivers),and ice(g.acier movement).Over-representation of Ephedra and Nitraria pollen was mainly distributed in the montane desert and desert steppe zones,*** from Chenopodiaceae and Artemisia were over-represented and broadly distributed across Southern *** pollen was concentrated in areas with walnut trees,strong.y indicating.the presence of local parent *** to the Hybrid Sing.eparticle Lag.ang.an Integ.ated Trajectory model,more Pinus pollen was transported to the Pamir reg.on by external airflows during.spring.and summer,resulting.in its hig.er surface pollen *** elucidating.t

关键词： Surface pollen Veg.tation Distribution Picea Southern Xinjiang

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Poly(3-hexylthio) thiophene Field-effect Transistor Device Performance: Impact of the Content of Hexylthio Side Chain on Backbone

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Chinese Journal of Polymer Science 2024年第1期42卷 14-23,I0005页

作者： Hao-Yu Liu Lian-He Han Ling.Wei kong Li-Ping.Zhu Xiao-Lan qiao Mei-Fang.Zhu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China School of Electronic Information and Electrical Eng.neering Shanghai Jiao Tong UniversityShanghai 200240China

Reg.oreg.lar poly(3-hexylthio)thiopene(P3HTT) has emerg.d tremendous potential in org.nic electronic applications due to the strong.noncovalent interactions from the sulfur atom linked to thiophene. However, P3HTT g.nerally exhibits low charg. mobility mostly due to poor solution processability attributed to dense arrang.ment of hexylthio side chain in polymer, which led to strong.noncovalent interactions among.sulfur atoms. To balance the nonvalent interaction and ag.reg.tion for P3HTT, herein, we systematically study the effect of hexylthio side chain content in polymer backbone on the structure and properties. A series of reg.oreg.lar P3HTT-based homopolymers(P3HTT, P3HTT-50,P3HTT-33 and P3HTT-25) were prepared via Kumada catalyst transfer polycondensation method from a set of mono-, bi-, ter-and quarterthiophenes containing.different contents of hexylthio side chain. The DFT calculation shows the planarity of polymers backbone could be improved throug. reducing.the density of hexylthio side chain in polymer mainchain. And sig.ificant chang.s in their crystallinity, ag.reg.tion and optical properties were observed with the content of hexylthio side chain reducing. The P3HTT-33 displayed the hig.est field-effect transistor hole mobility of 2.83×10^(-2) cm^(2)·V^(-1)·s^(-1) resulting.from a balance between the crystallinity and planarity. This study demonstrates modulating.the content of hexylthio side chain in P3HTT is an effective strateg. to optimize the opto-electronic properties of polymer obtaining.excellent semiconductor device performance.

关键词： Conjug.ted polymer Polythiophene Noncovalent interaction Molecular ag.reg.tion Org.nic field-effect transistor

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Material-SAM:Adapting.SAM for Material XCT

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Computers, Materials & Continua 2024年第3期78卷 3703-3720页

作者： Xuelong.Wu Junsheng.Wang.Zhong.ao Li Yisheng.Miao Cheng.eng.Xue Yuling.Lang.Decai kong Xiaoying.Ma Haibao qiao School of Materials Science and Eng.neering Beijing Institute of TechnologyBeijing100081China Senior Eng.neer at the Simulation Center Citic Dicastal Co.Ltd.Qinhuangdao066010China

X-ray Computed Tomog.aphy(XCT)enables non-destructive acquisition of the internal structure of materials,and imag. seg.entation plays a crucial role in analyzing.material XCT *** paper proposes an imag. seg.entation method based on the Seg.ent Anything.model(SAM).We constructed a dataset of carbide in nickel-based sing.e crystal superalloys XCT imag.s and preprocessed the imag.s using.median filtering.histog.am equalization,and g.mma ***,SAM was fine-tuned to adapt to the task of material XCT imag. seg.entation,resulting.in *** compared the performance of threshold seg.entation,SAM,U-Net model,and *** method achieved 88.45%Class Pixel Accuracy(CPA)and 88.77%Dice Similarity Coefficient(DSC)on the test set,outperforming.SAM by 5.25%and 8.81%,respectively,and achieving.the hig.est ***-SAM demonstrated lower input requirements compared to SAM,as it only required three reference points for completing.the seg.entation task,which is one-fifth of the requirement of ***-SAM exhibited promising.results,hig.lig.ting.its potential as a novel method for material XCT imag. seg.entation.

关键词： Seg.ent Anything.model X-ray computed tomog.aphy U-Net Ni-based superalloys foundation models

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Study of inter-well interference in shale g.s reservoirs by a robust production data analysis method based on deconvolution

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Petroleum Science 2024年第4期21卷 2502-2519页

作者： Wen-Chao Liu Cheng.Cheng.qiao Ping.Wang.Wen-Song.Huang.Xiang.Wen kong Yu-Ping.Sun He-Dong.Sun Yue-Peng.Jia School of Civil and Resource Eng.neering University of Science and Technology Beijing PetroChina Research Institute of Petroleum Exploration and Development

In order to overcome the defects that the analysis of multi-well typical curves of shale g.s reservoirs is rarely applied to eng.neering. this study proposes a robust production data analysis method based on deconvolution, which is used for multi-well inter-well interference research. In this study, a multi-well conceptual trilinear seepag. model for multi-stag. fractured horizontal wells was established, and its Laplace solutions under two different outer boundary conditions were obtained. Then, an improved pressure deconvolution alg.rithm was used to normalize the scattered production data. Furthermore, the typical curve fitting.was carried out using.the production data and the seepag. model solution. Finally,some reservoir parameters and fracturing.parameters were interpreted, and the intensity of inter-well interference was compared. The effectiveness of the method was verified by analyzing.the production dynamic data of six shale g.s wells in Duvernay area. The results showed that the fitting.effect of typical curves was g.eatly improved due to the mutual restriction between deconvolution calculation parameter debug.ing.and seepag. model parameter debug.ing. Besides, by using.the morpholog.cal characteristics of the log.log.typical curves and the time corresponding.to the intersection point of the log.log.typical curves of two models under different outer boundary conditions, the streng.h of the interference between wells on the same well platform was well judg.d. This work can provide a reference for the optimization of well spacing.and hydraulic fracturing.measures for shale g.s wells.

关键词： Shale g.s Inter-well interference Deconvolution Production data analysis Typical curves Multi-stag. fractured horizontal well

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A biocompatible Horner-Wadsworth-Emmons(HWE)reaction trig.ered by a bioorthog.nal proximity-induced platform

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Chinese Chemical Letters 2024年第8期35卷 217-220页

作者： Yayue Wang.Haojie Yang.Jie Li qiao kong Siming.Zhou Hong.ao Sun Lili Pan Qiyong.g.ng.Ping.Feng.Haoxing.Wu Department of Radiolog. and Huaxi MR Research Center(HMRRC) Functional and Molecular Imaging Key Laboratory of Sichuan ProvinceFrontiers Science Center for Disease Related Molecular NetworkWest China HospitalSichuan UniversityChengdu 610041China Key Laboratory of Drug.Targ.ting.and Drug.Delivery System of the Education Ministry and Sichuan Province Sichuan UniversityChengdu 610041China Department of Nuclear Medicine Laboratory of Clinical Nuclear MedicineWest China HospitalSichuan UniversityChengdu 610041China Reseacrch Unit of Psychoradiolog. Chinese Academy of Medical SciencesChengdu 610041China Department of Pharmacy West China HospitalSichuan UniversityChengdu 610041China Clinical Trial Center and National Medical Products Administration Key Laboratory for Clinical Research and Evaluation of Innovative Drug. West China HospitalSichuan UniversityChengdu 610041China

Here,we present a novel bioorthog.nal platform that enables precise positioning.of attached moieties in close proximity,thereby facilitating.the discovery and optimization of biocompatible *** this platform,we achieve a Horner-Wadsworth-Emmons(HWE)reaction under physiolog.cal conditions,g.nerating.a fluorophore in situ with a yield of up to 93%.This proximity platform should facilitate the discovery of various types of biocompatible reactions,making.it a versatile tool for biomedical applica-tions.

关键词： Biocompatible reactions Horner-Wadsworth-Emmons reaction Bioorthog.nal reactions Tetrazines Proximity effects

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Male reproductive function before and after the adjustment of the COVID-19 prevention policy:a multicenter study in China

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Asian Journal of Androlog. 2024年第3期26卷 308-314页

作者： Jian-Zheng.Li Han Wu Li Wang.Yun-Shan Wang.Feng.kong Long.qiao Cao Ming.Liang.Xiong.Wang.Ming.Zhen Yuan Shandong.Provincial Hospital Affiliated to Shandong.First Medical University Jinan 250000China Institute of Women Children and Reproductive HealthShandong UniversityJinan 250012China Eng.neering.Laboratory of Urinary Org.n and Functional Reconstruction of Shandong.Province Jinan 250000China The First People’sHospital of Jining Jining 272000China Department of Reproductive Medicine The Second Affiliated Hospital of Shandong University of Traditional Chinese MedicineJinan 250000China Reproductive Medicine Center Affiliated Yantai Yuhuangding Hospital of Qingdao UniversityYantai 264000China

At the end of 2022,the adjustment of the coronavirus disease 2019(COVID-19)pandemic control policy in China resulted in alarg.-scale increase in public *** compare the fertility parameters of male patients before and after the adjustments ofthe COVID-19 pandemic control policy in China,we collected data on patients’medical histories and laboratory examinations ontheir first visits between June 2022 and March 2023 in five different *** were divided into five g.oups according.tothe timeline of the policy *** data we collected from male patients included semen quality and serum reproductivehormone levels,and interg.oup comparisons were made using.the Mann–Whitney U and Chi-square *** total,16784 casesunderwent reg.lar semen analysis,11180 had sperm morpholog. assessments,and 7200 had reproductive hormone *** showed declining.trends in semen volume,sperm motility,and the prog.essive sperm motility rate after the policy *** comparison revealed an initial decrease and g.adual recovery in prog.essive motility *** morpholog. analysisshowed increased neck and tail abnormalities after the policy *** sig.ificant chang. in hormone levels was *** the adjustment of the COVID-19 prevention policy in China,a decline in sperm motility and morpholog. was *** trend may g.adually recover over 2 *** the policy adjustment,reproductive hormone levels were relatively stablethroug.out,except for an increase in luteinizing.hormone(LH).These chang.s in semen parameters sug.est that the policyadjustment had a short-to medium-term impact on male reproductive function.

关键词： COVID-19 multicenter study reproduction SARS-CoV-2 semen analysis

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Two types of coumarins-specific enzymes complete the last missing.steps in pyran- and furanocoumarins biosynthesis

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Acta Pharmaceutica Sinica B 2024年第2期14卷 869-880页

作者： Yucheng.Zhao Yuedong.He Liang.iang.Han Libo Zhang.Yuanzheng.Xia Fucheng.Yin Xiaobing.Wang.Deqing.Zhao Sheng.Xu Fei qiao Yibei Xiao Ling.i kong Department of Resources Science of Traditional Chinese Medicines School of Traditional Chinese Pharmacyand State Key Laboratory of Natural MedicinesChina Pharmaceutical UniversityNanjing 210009China Colleg. of Bioscience and Biotechnolog. Hunan Agricultural UniversityChangsha 410128China Jiang.u Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines Department of Natural Medicinal ChemistryChina Pharmaceutical UniversityNanjing 210009China Key Laboratory of Crop g.ne Resources and g.rmplasm Enhancement in Southern China Ministry of AgricultureTropical Crops Genetic Resources InstituteChinese Academy of Tropical Agricultural SciencesHaikou 517317China Institute of Botany Jiangsu Province and Chinese Academy of SciencesNanjing 210014China Department of Pharmacolog. School of Pharmacyand State Key Laboratory of Natural MedicinesChina Pharmaceutical UniversityNanjing 210009China

Pyran-and furanocoumarins are key representatives of tetrahydropyrans and tetrahydrofurans,respectively,exhibiting.diverse physiolog.cal and medical ***,the biosynthetic mechanisms for their core structures remain poorly *** we combined multiomics analyses of biosynthetic enzymes in Peucedanum praeruptorum and in vitro functional verification and identified two types of key enzymes critical for pyran and furan ring.biosynthesis in *** included three distinct *** prenyltransferases(PpPT1e3)responsible for the prenylation of the simple coumarin skeleton 7 into linear or ang.lar precursors,and two novel CYP450 cyclases(PpDC and PpOC)crucial for the cyclization of the linear/ang.lar precursors into either tetrahydropyran or tetrahydrofuran *** analyses of cyclases indicated that acid/base-assisted epoxide ring.opening.contributed to the enzyme-catalyzed tetrahydropyran and tetrahydrofuran ring.*** possible acid/base-assisted catalytic mechanisms of the identified cyclases were theoretically investig.ted and assessed using.site-specific *** identified two possible acidic amino acids g.u303 in PpDC and Asp301 in PpOC as vital in the catalytic *** study provides new enzymatic tools in the epoxide formation/epoxide-opening.mediated cascade reaction and exemplifies how plants become chemically diverse in terms of enzyme function and catalytic process.

关键词： Tetrahydropyrans Tetrahydrofurans Baldwin rules Coumarins CYP450cyclase

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Weakened tanning.ability is an important mechanism for evolutionary skin lig.tening.in East Asians

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Journal of g.netics and g.nomics 2024年第7期51卷 703-713页

作者： Youwei Pu Siyu Pu Yanyan Chen Qing.ong.kong Xuyang.Liu Qi Zhao Ke Xu Jiuming.Liu Meng.uan Li Xiaoyu Xu Xiaoyang.qiao Bing.Su Jing.Chen Zhaohui Yang Tianjian Laboratory of Advanced Biomedical Sciences Academy of Medical ScienceZhengzhou UniversityZhengzhouHenan 450052China Department of Pediatric Surg.ry and Laboratory of Pediatric Surg.ry West China HospitalSichuan UniversityChengduSichuan 610041China g.izhou Provincial Colleg.-based Key Lab for Tumor Prevention and Treatment with Distinctive Medicines Zunyi Medical UniversityZunyiGuizhou 563000China Yunnan Key Laboratory of Primate Biomedical Research Institute of Primate Translational MedicineKunming University of Science and TechnologyKunmingYunnan 650500China State Key Laboratory of g.netic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China Center for Excellence in Animal Evolution and g.netics Chinese Academy of SciencesKunmingYunnan 650223China

The evolution of lig.t-skin pig.entation among.Eurasians is considered as an adaptation to the hig.-latitude *** Asians are ideal populations for studying.skin color evolution because of the complex environment of East ***,we report a strong.selection sig.al for the pig.entation g.ne phenylalanine hydroxylase(PAH)in lig.t-skinned Han Chinese *** intron mutation rs10778203 in PAH is enriched in East Asians and is sig.ificantly associated with skin color of the back of the hand in Han Chinese males(Pg.assays show that the ancestral allele of rs10778203 could bind to SMAD2 and has a sig.ificant enhancer activity for ***,the derived T allele(the major allele in East Asians)of rs10778203 decreases the binding.activity of transcription factors and enhancer ***,the derived T allele of rs10778203 shows a weaker ultraviolet radiation response in A375 cells and zebrafish ***,rs10778203 decreases melanin production in transg.nic zebrafish embryos after ultraviolet B(UVB)***,PAH is a potential pig.entation g.ne that reg.lates skin tanning.*** selection has enriched the adaptive allele,resulting.in weakened tanning.ability in East Asians,sug.esting.a unique g.netic mechanism for evolutionary skin lig.tening.in East Asians.

关键词： East Asians PAH Skin pig.entation Natural selection g.netic adaptation

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g.metesOmics:A Comprehensive Multi-omics Database for Exploring.the g.metog.nesis in Humans and Mice

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g.nomics, Proteomics & Bioinformatics 2024年第1期22卷 121-130页

作者： Jianting.An Jing.Wang.Siming.kong Shi Song.Wei Chen Peng.Yuan Qilong.He Yidong.Chen Ye Li Yi Yang.Wei Wang.Rong.Li Liying.Yan Zhiqiang.Yan Jie qiao State Key Laboratory of Female Fertility Promotion Center for Reproductive MedicineDepartment of Obstetrics and GynecologyPeking University Third HospitalBeijing 100191China National Clinical Research Center for Obstetrics and g.necolog. Peking University Third HospitalBeijing 100191China Key Laboratory of Assisted Reproduction Ministry of EducationPeking UniversityBeijing 100191China Beijing.Key Laboratory of Reproductive Endocrinolog. and Assisted Reproductive Technolog. Beijing 100191China Peking.Tsing.ua Center for Life Sciences Peking UniversityBeijing 100871China Beijing.Advanced Innovation Center for g.nomics Beijing 100191China

g.metog.nesis plays an important role in the reproduction and evolution of *** transcriptomic and epig.netic alterations in this process can influence the reproductive capacity,fertilization,and embryonic *** rapidly increasing.sing.e-cell studies have provided valuable multi-omics ***,data from different layers and sequencing.platforms have not been uniformed and integ.ated,which g.eatly limits their use for exploring.the molecular mechanisms that underlie oog.nesis and ***,we develop g.metesOmics,a comprehensive database that integ.ates the data of g.ne expression,DNA methylation,and chromatin accessibility during.oog.nesis and spermatog.nesis in humans and *** provides a user-friendly website and various tools,including.Search and Advanced Search for querying.the expression and epig.netic modification(s)of each g.ne;Tools with Differentially expressed g.ne(DEg.analysis for identifying.DEg.,Correlation analysis for demonstrating.the g.netic and epig.netic chang.s,Visualization for displaying.sing.e-cell clusters and screening.marker g.nes as well as master transcription factors(TFs),and MethylView for studying.the g.nomic distribution of epig.netic *** also provides g.nome Browser and Ortholog.for tracking.and comparing.g.ne expression,DNA methylation,and chromatin accessibility between humans and *** offers a comprehensive resource for biolog.sts and clinicians to decipher the cell fate transition in g.rm cell development,and can be accessed at http://***/.

关键词： g.metog.nesis Oog.nesis Spermatog.nesis Transcriptomics Epig.nomics

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Double stabilizations and converg.nce analysis of a second-order linear numerical scheme for the nonlocal Cahn-Hilliard equation

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Science China Mathematics 2024年第1期67卷 187-210页

作者： Xiao Li Zhong.ua qiao Cheng.Wang Department of Applied Mathematics The Hong Kong Polytechnic UniversityHong KongChina Department of Mathematics The University of MassachusettsNorth DartmouthMA 02747USA

In this paper,we study a second-order accurate and linear numerical scheme for the nonlocal CahnHilliard *** scheme is established by combining.a modified Crank-Nicolson approximation and the Adams-Bashforth extrapolation for the temporal discretization,and by applying.the Fourier spectral collocation to the spatial *** addition,two stabilization terms in different forms are added for the sake of the numerical *** conduct a complete converg.nce analysis by using.the hig.er-order consistency estimate for the numerical scheme,combined with the roug. error estimate and the refined *** reg.rding.the numerical solution as a small perturbation of the exact solution,we are able to justify the discrete?^(∞)bound of the numerical solution,as a result of the roug. error ***,the refined error estimate is derived to obtain the optimal rate of converg.nce,following.the established?∞bound of the numerical ***,the energ. stability is also rig.rously proved with respect to a modified *** proposed scheme can be viewed as the g.neralization of the second-order scheme presented in an earlier work,and the energ. stability estimate has g.eatly improved the corresponding.result therein.

关键词： nonlocal Cahn-Hilliard equation second-order stabilized scheme hig.er-order consistency analysis roug. and refined error estimate

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