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Reevaluation by the CRISPR/Cas9 knockout approach revealed that multiple pluripotency-associated lncRNAs are dispensable for pluripotency maintenance while Snora73a/b is essential for pluripotency exit

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Science China(life Sciences) 2024年第10期67卷 2198-2212页

作者： zhen li Xuefei li Jingxia lin Yangming Wang Huiqing Cao Jiajian Zhou Institute of Molecular Medicine College of Future TechnologyPeking UniversityBeijing 100871China Dermatology Hospital Southern Medical UniversityGuangzhou 510091China Beijing Advanced Center of RNA Biology(BEACON) Peking UniversityBeijing 100871China

Many long noncoding RNAs(lncRNAs)have been identified through siRNA-based screening as essential regulators of embryonic stem cell(ESC)***,the biological and molecular functions of most lncRNAs remain ***,we employed CRISPR/Cas9-mediated knockout technology to explore the functions of 8 lncRNAs previously reported to promote pluripotency in mouse ***,all of these lncRNAs were dispensable for pluripotency maintenance and proliferation in mouse ESCs when disrupted individually or in ***-cell transcriptomic analysis also showed that the knockout of these lncRNAs has a minimal impact on pluripotency gene expression and cell *** further showed that several small hairpin RNAs(shRNAs)previously used to knock down lncRNAs caused the downregulation of pluripotency genes in the corresponding lncRNA-knockout ESCs,indicating that off-target effects likely responsible for the pluripotency defects caused by these ***,linc1343-knockout and linc1343-knockdown ESCs failed to form cystic structures and exhibited high expression of pluripotency genes during embryoid body(EB)*** reintroducing RNA products generated from the linc1343 locus,we found that two snoRNAs,Snora73a and Snora73b,but not lncRNAs,could rescue pluripotency silencing defects during EB differentiation of linc1343 knockout *** results suggest that the 8 previously annotated pluripotency-regulating lncRNAs have no overt functions in conventional ESC culture;however,we identified snoRNA products derived from an annotated lncRNA locus as essential regulators for silencing pluripotency genes.

关键词： long noncoding RNAs embryonic stem cells CRISPR/Cas9 snoRNAs stem cell differentiation

Asymmetric alkenylation reaction of benzoxazinones with diarylethylenes catalyzed by B(C_(6)F_(5))_(3)/chiral phosphoric acid

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Chinese Chemical Letters 2024年第5期35卷 135-140页

作者： zhen liu Zhi-Yuan Ren Chen Yang Xiangyi Shao li Chen Xin li State Key Laboratory of Elemento-Organic Chemistry Frontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China zhenhai High School of Zhejiang Ningbo 315299China

Catalytic enantioselective alkenylation is an efficient method to construct chiral alkene molecules,but the asymmetric alkenylation of simple alkenes catalyzed by metal-free catalysts remains an elusive ***,we reported an asymmetric alkenylation of benzoxazinones with diarylethylenes by utilizing a B(C_(6)F_(5))_(3)/chiral phosphoric acid catalyst.A broad of benzoxazinones and diarylethylenes with electron-withdrawing and electron-donating groups were tolerated(up to 95%yield and 97.5:2.5 e.r.)in the methodology under mild reaction ***,the synthetic utility was confirmed by the scaled-up reaction and transformations of the *** mechanism was preliminarily explored by control reactions,nonlinear effect experiment and DFT calculations.

关键词： Asymmetric alkenylation Simple alkenes Benzoxazinones B(C_(6)F_(5))_(3)/chiral phosphoric acid Theoretical calculations

Exploring the mechanisms of calcium carbonate deposition on various substrates with implications for effective anti-scaling material selection

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Petroleum Science 2024年第4期21卷 2870-2880页

作者： Lu Gong fei-Yi Wu Ming-fei Pan Jun Huang Hao Zhang Jing-li Luo Hong-Bo Zeng College of Science China University of Petroleum Beijing Key Laboratory of Optical Detection Technology for Oil and Gas China University of Petroleum Basic Research Center for Energy Interdisciplinary College of Science China University of Petroleum Department of Chemical and Materials Engineering University of Alberta Key Laboratory of High Efficiency and Clean Mechanical Manufacture (Ministry of Education) School of Mechanical Engineering Shandong University

The unexpected scaling phenomena have resulted in significant damages to the oil and gas industries,leading to issues such as heat exchanger failures and pipeline clogging. It is of practical and fundamental importance to understand the scaling mechanisms and develop efficient anti-scaling strategies. However,the underlying surface interaction mechanisms of scalants(e.g., calcite) with various substrates are still not fully understood. In this work, the colloidal probe atomic force microscopy(AFM) technique has been applied to directly quantify the surface forces between calcite particles and different metallic substrates,including carbon steel(CR1018), low alloy steel(4140), stainless steel(SS304) and tungsten carbide,under different water chemistries(i.e., salinity and p H). Measured force profiles revealed that the attractive van der Waals(VDW) interaction contributed to the attachment of the calcium carbonate particles on substrate surfaces, while the repulsive electric double layer(EDL) interactions could inhibit the attachment behaviors. High salinity and acidic p H conditions of aqueous solutions could weaken the EDL repulsion and promote the attachment behavior. The adhesion of calcite particles with CR1018 and4140 substrates was much stronger than that with SS304 and tungsten carbide substrates. The bulk scaling tests in aqueous solutions from an industrial oil production process showed that much more severe scaling behaviors of calcite was detected on CR1018 and 4140 than those on SS304 and tungsten carbide, which agreed with surface force measurement results. Besides, high salinity and acidic p H can significantly enhance the scaling phenomena. This work provides fundamental insights into the scaling mechanisms of calcite at the nanoscale with practical implications for the selection of suitable antiscaling materials in petroleum industries.

关键词： Scaling phenomenon Metallic substrates Surface forces Bulk scaling tests

Phase Patterning of Poly(oxime-ester)for Information Encryption by Photo-induced Isomerization

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Chinese Journal of Polymer Science 2024年第10期42卷 1488-1494,I0010页

作者： Yu-Fan Yang Yun Bai Yi-Bao li Chang-fei He School of Chemistry and Chemical Engineering Gannan Normal UniversityGanzhou341000China

Crystal polymers or liquid crystal elastomers undergo a phase transition that results in a change in the corresponding optical properties,which has the potential to be applied in areas such as information encryption and *** utilization of these materials for patterning purposes requires different phase transition ***,once prepared,altering the phase transition temperature of them presents significant ***,a poly(oxime-ester)(POE)network is developed to achieve high-resolution and multilevel patterning by photo-induced *** as-prepared POE exhibits the ability to transition from an opaque state to a transparent state under temperature stimuli,with the transition temperature and kinetics dependent on UV light exposure ***,complex patterns and information can be encrypted through different selective regional exposure time and decrypted under specific temperature or cooling ***,we illustrate an example of temporal communication,where cooling time or temperature serves as the encoded *** research expands the application scope of advanced encryption materials,showcasing the potential of POE in dynamic information encryption and decryption processes.

关键词： Poly(oxime-ester) Isomerization Phase patterning Information encryption

Effect of dissolved organic nitrogen on the bloom of Prorocentrum donghaiense and Karenia spp. in the East China Sea coastal waters

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Acta Oceanologica Sinica 2024年第6期43卷 71-85页

作者： Xiaoru Cui Guangming zhen Jing Zhao Keqiang li Xiulin Wang Key Laboratory of Marine Chemistry Theory and Technology/Frontiers Science Center for Deep Ocean Multispheres and Earth System of Ministry of Education Ocean University of ChinaQingdao 266100China College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China

Understan ding the mechanism of harmful algal bloom formation is vital for effectively preventing algal bloom outbreaks in coastal *** *** in the East China Sea show a significant correlation with nutrient ***,the impact of key components of nutrients,especially dissolved organic nitrogen(DON),on the blooms of Karenia *** not *** research is still *** this study,the cruise observations,field mesocosm-flask culture experiments,and a multinitrogen-tri-phytoplankton-detritus model(NTPD) are combined to reveal the quantitative influence of nutrient regimes on the shift of Prorocentrum donghaiense and Karenia *** the East China *** has a synchronism rhythm of *** spp.-diatom loop in the field culture experiment,which is consistent with the results of the cruise *** results showed that the processes of terrigenous DON(TeDON) and dissolved inorganic nitrogen(DIN:NO_(3)^(-)-N,NH_(4)^(+)-N) absorption promoted *** to become the dominant algae in the community;whereas the processes of DON from *** absorption promoted Karenia *** become the dominant algae in ambient DIN *** addition,the three-dimensional fluorescence components of humus C,tyrosine and fulvic acid can indicate the processes of growth and extinction of *** and Karenia spp.,*** study infers that *** and Karenia *** shift mechanism associated with the nutrient regime in coastal waters,which provides a scientific basis for the environmental management of coastal eco system health.

关键词： Karenia spp. Prorocentrum donghaiense nutrients multinitrogen-tri-phytoplankton-detritus model three-dimensional fluorescence

On the Factors Influencing the High Stretch-Flangeability of a Low-Density 1180 MPa Fe-Mn-Al-C-Nbδ-QP Steel

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1291-1300页

作者： Dan‑Dan Cui Peng Chen Peng‑fei Wang Xiao‑Wu li Department of Materials Physics and Chemistry School of Materials Science and Engineeringand Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

Low-densityδ-quenching and partitioning(δ-QP)steels with excellent strength and ductility have been recently ***,there are still rare reports on the formability of δ-QP steels,which are critical for satisfying the manufacture of structural parts during the application in automotive *** the present work,an 1180 MPa Fe–Mn–Al–C–Nbδ-QP steel with a high ductility was adopted for the stretch–flangeability ***δ-QP steel was developed by separated quenching and partitioning processes.A good hole expansion ratio(HER)of 34.9±0.9%was obtained in the quenched steel,but it has been further increased to 52.2%by the tempering *** improved stretch–flangeability was attributed to the enhanced austenite stability and deformation *** the one hand,the stability of austenite was increased by carbon partitioning during tempering,which reduced crack possibility via the suppression of the fresh martensite *** the other hand,the tempering treatment released the internal stress caused by martensitic transformation and reduced the difference in strength among different phases,resulting in an increase in the resistance to crack initiation and propagation.

关键词： Hole expansion ratio Low-densityδ-quenching and partitioning(δ-QP)steel Stretch-flangeability Austenite stability Deformation uniformity

Extracting Integrated Features of Electronic Medical Records Big Data for Mortality and Phenotype Prediction

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Chinese Journal of Electronics 2024年第3期33卷 776-792页

作者： fei li Yiqiang CHEN Yang GU Yaowei WANG Institute of Computing Technology University of Chinese Academy of Sciences Pengcheng Laboratory

The key to synthesizing the features of electronic medical records(EMR) big data and using them for specific medical purposes,such as mortality and phenotype prediction,is to integrate the individual medical event and the overall multivariate time series feature extraction automatically,as well as to alleviate data imbalance *** paper provides a general feature extraction method to reduce manual intervention and automatically process large-scale *** processing uses two variational auto-encoders(VAEs) to automatically extract individual and global *** avoids the well-known posterior collapse problem of Transformer VAE through a uniquely designed "proportional and stabilizing" mechanism and forms a unique means to alleviate the data imbalance *** conducted experiments using ICU-STAY patients' data from the MIMIC-Ⅲ database and compared them with the mainstream EMR time series processing *** results show that the method extracts visible and comprehensive features,alleviates data imbalance problems and improves the accuracy in specific predicting tasks.

关键词： Databases Time series analysis MIMICs Manuals Big Data Feature extraction Transformers

Sedimentary Environment and Mineralization of the Black Shale Polymetallic Layer in the Early Cambrian,SW China:Constraints from in situ LA-ICP-MS Analysis of Pyrite

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 416-429页

作者： YANG zhen FU Yong li Chao CAI Xi GUO Chuan College of Eco-Environmental Engineering Guizhou Minzu UniversityGuiyang 550025China College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China Key Laboratory of Karst Georesources and the Environment Ministry of EducationGuizhou UniversityGuiyang 500025China National Research Center for Geoanalysis Chinese Academy of Geological SciencesBeijing 100037China

A polymetallic layer is usually developed at the bottom of the early Cambrian black shale in Guizhou *** mineral that makes up the polymetallic layer is related to the sedimentary *** analyze the differentiation mechanism between polymetallic deposits(Ni-Mo and V),the Zhijin Gezhongwu profile located in the outer shelf and the Sansui Haishan V deposit located in the lower slope are selected to study the in situ sulfur isotopes and trace elements of *** results show that δ^(34)S values of pyrite vary widely from−7.8‰to 28‰in the Gezhongwu profile,while the δ^(34)S values are relatively uniform(from 27.8‰to 38.4‰)in the Haishan *** isotopic S composition is consistent with the transition that occurs in the sedimentary phase from the shelf to the deep sea on the transgressive Yangtze platform;this indicates that the δ^(34)SO_(4)^(2−)values in seawater must be differently distributed in depositional *** sulfur in the Ni-Mo layer is produced after the mixing of seawater and hydrothermal fluid,while the V layer mainly originates from ***,the Ni-Mo and V deposits have been differentiated primarily on the basis of the combined effect of continental weathering and hydrothermal fluid.

关键词： sedimentary environment black shale polymetallic layer pyrite early Cambrian

Thermodynamic geometry of the RN-Ad S black hole and non-local observables

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Communications in Theoretical Physics 2024年第2期76卷 137-144页

作者： Chao Wang Bin Wu zhen-Ming Xu Wen-li Yang Institute of Physics Shaanxi University of TechnologyHanzhong 723000China School of Physics Northwest UniversityXi'an 710127China Institute of Modern Physics Northwest UniversityXi'an 710127China Shaanxi Key Laboratory for Theoretical Physics Frontiers Xi'an 710127China Peng Huanwu Center for Fundamental Theory Xi'an 710127China

This paper studies the thermodynamic geometry of the Reissner–Nordstr?m-anti-de Sitter(RN-AdS)black hole via detection of the non-local observables in the dual field theory,including the entanglement entropy and equal-time two-point correlation *** the dimensional analysis,we construct the principle of corresponding states of black hole *** a result,our findings can be applied to black holes with different Ad S *** this sense,the probe of the thermodynamic geometry of the RN-Ad S black hole though the non-local observables in dual field theory has been confirmed numerically.

关键词： black hole thermodynamic thermodynamic geometry phase transition non-local observables