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Interplay of RNA-binding proteins controls germ cell development in zebrafish

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Journal of Genetics and Genomics 2024年第9期51卷 889-899页

作者： de-li Shi Laboratory of developmental Biology CNRS-UMR7622Institut de Biologie Paris-Seine(IBPS)Sorbonne University75005 ParisFrance

The specification of germ cells in zebrafish mostly relies on an inherited mechanism by which localized maternal determinants,called germ plasm,confer germline fate in the early *** studies have partially allowed the identification of key regulators governing germ plasm formation and subsequent germ cell ***-binding proteins,acting in concert with other germ plasm components,play essential roles in the organization of the germ plasm and the specification,migration,maintenance,and differentiation of primordial germ *** loss of their functions impairs germ cell formation and causes sterility or sexual *** is emerging that they instruct germline development through differential regulation of mRNA fates in somatic and germ ***,the challenge remains to decipher the complex interplay of maternal germ plasm components in germ plasm compartmentalization and germ cell *** failure to control the developmental outcome of germ cells disrupts the formation of gametes,it is important to gain a complete picture of regulatory mechanisms operating in the germ cell *** review sheds light on the contributions of RNA-binding proteins to germ cell development in zebrafish and highlights intriguing questions that remain open for future investigation.

关键词： Germplasm Primordialgerm cell Germlinestem cell Gametogenesis Zebrafish RNA-binding protein Posttranscriptional gene expression Translational activation and repression

Focus on research advances in the natural gas hydrate resource evaluation: Introduction to papers in the special section of Evaluation of Natural Gas Hydrate Resource Potential in the South China Sea

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Petroleum Science 2022年第1期19卷 1-2页

作者： de-li Gao Academician of Chinese Academy of Sciences Professor at China University of PetroleumBeijing 100083China

The continental hydrocarbon generation theory has opened a new field of oil and gas development and once solved the oil and gas shortage problem in *** then,geological theories of coalbed methane accumulation,foreland basin oil and gas accumulation,carbonate rock oil and gas accumulation,superimposed basin,and deep oil and gas accumulation have contributed to relieving the pressure of oil and gas shortage in China.

关键词： China. basin carbonate

Analysis of drilling difficulty of extended-reach wells based on drilling limit theory

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Petroleum Science 2022年第3期19卷 1099-1109页

作者： Wen-Jun Huang de-li Gao MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China

With the continuous increase in vertical depths and horizontal displacements of directional wells,the difficulties of drilling operations continue to increase,and more accurate methods of drilling difficulty evaluation are *** this paper,a drilling difficulty evaluation method is built by combining drilling limit model and expert ***,the concept of drilling difficulty index is introduced,and the method to calculate drilling difficulty index is ***,the meanings of five drilling difficulty levels are explained and the optimization design method with drilling difficulty as the target is *** last,the theoretical model is applied to the extended-reach drilling of the liuhua oilfield in the South China Sea,in which drilling difficulties are evaluated and the relationship between drilling difficulty and development control radius is *** results indicate that extended-reach drilling in the liuhua oilfield is on the“normal”difficulty level on average,rotary drilling in 8_(1/2)-*** is the most difficult,and the main constraint conditions are excessive torque and high *** technology upgradation,the drilling difficulties are decreased,the development control radius increases from 6.6 to 11.4 km,and the maximum horizontalto-vertical ratio increases from 5.3 to ***,the development wells in marginal oilfields and adjustment wells in old oilfields can be drilled on“normal”difficulty ***,technology upgradation,especially drilling rig upgradation,is the most important development direction for extended-reach drilling in the South China Sea.

关键词： Extended-reach drilling South China Sea Drilling limit Drilling difficulty evaluation Drilling optimization design

Prediction models of burst strength degradation for casing with considerations of both wear and corrosion

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Petroleum Science 2024年第1期21卷 458-474页

作者： Jie-li Wang Wen-Jun Huang de-li Gao MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China

Casing wear and casing corrosion are serious problems affecting casing integrity failure in deep and ultra-deep *** paper aims to predict the casing burst strength with considerations of both wear and ***,the crescent wear shape is simplified into three categories according to common mathematical ***,based on the mechano-electrochemical(M-E)interaction,the prediction model of corrosion depth is built with worn depth as the initial condition,and the prediction models of burst strength of the worn casing and corroded casing are ***,the accuracy of different prediction models is validated by numerical simulation,and the main influence factors on casing strength are *** last,the theoretical models are applied to an ultra-deep well in Northwest China,and the dangerous well sections caused by wear and corrosion are predicted,and the corrosion rate threshold to ensure the safety of casing is *** results show that the existence of wear defects results in a stress concentration and enhanced M-E interaction on corrosion depth *** accuracy of different mathematical models is different:the slot ring model is most accurate for predicting corrosion depth,and the eccentric model is most accurate for predicting the burst strength of corroded *** burst strength of the casing will be overestimated by more than one-third if the M-E interaction is neglected,so the coupling effect of wear and corrosion should be sufficiently considered in casing integrity evaluation.

关键词： deep well Casing integrity Casing wear Casing corrosion Burst strength

On the Relationship Between the Baum-Katz-Spitzer Complete Convergence Theorem and the Law of the Iterated Logarithm

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Acta Mathematica Sinica,English Series 2007年第4期23卷 599-612页

作者： de li li Andrew ROSALSKY Andrei VOLODIN department o/Mathematical Sciences Lakehead University Thunder Bay ON Canada P7B 5E1 department of Statistics University of Florida Gainesville FL 32611 USA department of Mathematics and Statistics University of Regina Regina SK Canada S4S 0A2

For a sequence of i.i.d. Banach space-valued random variables {Xn; n ≥ 1} and a sequence of positive constants {an; n ≥ 1}, the relationship between the Baum-Katz-Spitzer complete convergence theorem and the law of the iterated logarithm is investigated. Sets of conditions are provided under which （i） lim sup n→∞ ｜｜Sn｜｜/an〈∞ *** ∞ ∑n=1（1/n）P（｜｜Sn｜｜/an ≥ε〈∞for all ε 〉 λ for some constant λ ∈ [0, ∞） are equivalent;（ii） For all constants λ ∈ [0, ∞）,lim sup ｜｜Sn｜｜/an =λ *** ^∞∑ n=1（1/n） P（｜｜Sn｜｜/an ≥ε）{〈∞, if ε〉λ =∞,if ε〈λare equivalent. In general, no geometric conditions are imposed on the underlying Banach space. Corollaries are presented and new results are obtained even in the case of real-valued random variables.

关键词： partial sums of i.i.d. Banach space-valued random variables Baum-Katz-Spitzer complete convergence theorem law of the iterated logarithm almost sure convergence

Tribocorrosion Behavior of 304 Stainless Steel in 0.5 mol/L Sulfuric Acid

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Acta Metallurgica Sinica(English Letters) 2018年第10期31卷 1049-1058页

作者： Ming liu de-li Duan Sheng-li Jiang Ming-Yang li Shu li Institute of Metal Research Chinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China

The tribocorrosion behavior of 304 stainless steel was studied through comparing the damage behavior of 304 stainless steel in dilute sulfuric acid to that in distilled water by a reciprocating tribotester. The re-passivation behavior, the surface and sectional morphological features, as well as the change of microhardness of samples were studied, and the tribocorrosion mechanism was also discussed. The experimental results reveal that the damage of stainless steel in dilute sulfuric acid was caused by the steel＇s mechanical removal and electrochemical dissolution. The wear mechanism of stainless steel is abrasive wear, which mainly consists of micro-cutting and peeling. The synergetic action between corrosion and wear is notable. The corrosive environment leads to the embrittlement of the surface layer, and the wear destroys the passivation film and causes galvanic corrosion.

关键词： Stainless steel Tribocorrosion Synergetic action Reciprocating wear test Re-passivation

Measurements of spectral lines observed with Hinode/EIS as implications for coronal heating

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Research in Astronomy and Astrophysics 2009年第7期9卷 829-840页

作者： Ying li Ming-de Ding department of Astronomy Nanjing University Nanjing 210093 China

We have measured the line widths and nonthermal velocities in 12 solar regions using high resolution EUV data taken by Hinode/EIS. We find that there exists a positive correlation between the intensity and nonthermal velocity for the Fe xII emission line as well as some other lines. The correlation coefficients decrease from the disk center to the limb. However, the nonthermal velocities of a particular spectral line do not vary much in different regions, so they are considered isotropic. In particular, we find that for a coronal loop structure, the largest widths and nonthermal velocities occur at the footpoints, where outflows appear. Based on these observational results, we discuss several physical processes responsible for coronal heating.

关键词： line: profiles - Sun: corona - Sun: UV radiation

Estimation of glacier ice storage in western China constrained by field ground-penetrating Radar surveys

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Advances in Climate Change Research 2022年第3期13卷 359-374页

作者： Peng-Bin liANG li-de TIAN Institute of International Rivers and Eco-Security Yunnan UniversityKunming 650500China Yunnan Key Laboratory of International Rivers and Transboundary Eco-security Kunming 650091China

Recent decades have witnessed the accelerated retreat of alpine glaciers,which likely portends a decline in the glacial ice melt on which large downstream populations rely for ***,estimating water storage in alpine glaciers is critical for predicting the trend of glacier *** study compiled a rich set of ice thickness observations for glaciers of varying sizes in western *** here presented a first-order assessment of the various errors involved in interpreting ice thickness from ground-penetrating radar(GPR)*** empirical Bayesian kriging(EBK)method was used for ice thickness interpolation and volume *** then established a new volume-scaling law specific to western China glaciers based on these 36 volume-area *** together with the Second Chinese Glacier Inventory(SCGI),we obtain a regional volume estimate of 4451±298 km^(3).By comparison,we believed that this result is the most reliable estimate of the total ice storage in western China and more reliably predicts gross glacier ***,our results show that the method of glacier division can strongly affect the total volume estimation,which previous studies *** emphasizes the need for more surveyed glaciers data and more accurate glacier inventory to improve the evaluation of the climate impact on glacier melting water resources and to help ensure the future survival of these alpine glaciers.

关键词： Ground-penetrating radar Glacier thickness survey Glacier volume volume-area scaling law Distributed model Western China

The legacy effects of rubber defoliation period on the refoliation phenology,leaf disease,and latex yield

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Plant Diversity 2023年第1期45卷 98-103页

作者： de-li Zhai Jian-Chu Xu Center for Mountain Futures Kunming Institute of BotanyKunming 650201YunnanChina Institute of Environment and Ecology School of the Environment and Safety EngineeringJiangsu University301 Xuefu RoadZhenjiang212013Jiangsu ProvinceChina Key Laboratory for Economic Plants and Biotechnology Kunming Institute of BotanyChinese Academy of Sciences132 Lanhei RoadKunming 650201YunnanChina East and Central Asia Regional Office World Agroforestry(ICRAF)Kunming 650201YunnanChina

The leaf phenology of trees has received particular attention for its crucial role in the global water and carbon balances,ecosystem,and species ***,current studies on leaf phenology have mainly focused on temperate trees,while few studies including tropical *** attention has been paid to globally extensive industrial *** plantations are important to both the local and global *** this study,we investigated the legacy effects of defoliation phenology on the following year’s leaf flushing,leaf disease,and also latex yield of rubber trees,an economically important tree to local people and the *** show that extended duration of defoliation increased the subsequent duration of refoliation and rates of infection by powdery mildew disease,but led to reduced latex yield in *** legacy effect of rubber defoliation may relate to the carbohydrate reserved in the trees.A longer duration of defoliation would consume more reserved carbohydrates,reducing available reserves for disease defense and latex *** duration of defoliation period was associated with either a lower temperature before the cessation of latex tapping in October-November and/or a higher temperature after the cessation of latex tapping in *** falling signals the end of photosynthetic activities in deciduous ***,the leaf falling phenology will impact ecological processes involving rubber *** findings indicated that the inclusion of defoliation periods in future rubber trees’ research,will be crucial to furthering our understanding of leaf flushing,powdery mildew disease,and latex yield.

关键词： Carbohydrate defoliation Legacy effect Phenology Rubber trees