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Meiotic transcriptional reprogramming mediated by cell-cell communications in humans and mice revealed by scATACseq and scRNA-seq

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Zoological Research 2024年第3期45卷 601-616页

作者： Hai-Quan Wang Xiao-Long Wu Jing Zhang Si-Ting Wang Yong-Juan Sang Kang li chao-Fan Yang Fei Sun chao-jun li State Key Laboratory of Reproductive Medicine and Offspring Health Center for Global HealthSchool of Public HealthNanjing Medical UniversityNanjingJiangsu 211166China Medical School Nanjing UniversityNanjingJiangsu 210093China Zhejiang University School of Medicine HangzhouZhejiang 310016China Department of Urology and Andrology Sir Run Run Shaw HospitalZhejiang University School of MedicineHangzhouZhejiang 310000China Model Animal Research Center of Medical School Nanjing UniversityNanjingNanjingJiangsu 210093China liangzhu Laboratory Zhejiang UniversityHangzhouZhejiang 311121China

Meiosis is a highly complex process significantly influenced by transcriptional ***,studies on the mechanisms that govern transcriptomic changes during meiosis,especially in prophase I,are ***,we performed single-cell ATAC-seq of human testis tissues and observed reprogramming during the transition from zygotene to pachytene *** event,conserved in mice,involved the deactivation of genes associated with meiosis after reprogramming and the activation of those related to spermatogenesis before their functional ***,we identified 282 transcriptional regulators(TRs)that underwent activation or deactivation subsequent to this *** suggested that physical contact signals from Sertoli cells may regulate these TRs in spermatocytes,while secreted ENHO signals may alter metabolic patterns in these *** results further indicated that defective transcriptional reprogramming may be associated with non-obstructive azoospermia(NOA).This study revealed the importance of both physical contact and secreted signals between Sertoli cells and germ cells in meiotic progression.

关键词： Single-cell RNA-seq Single-cell ATAC-seq Spermatogenesis Meiosis Transcriptional reprogramming Cell-cell communication

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On Inventing Cross-Dehydrogenative Coupling(CDC):Forming C-C Bond from Two Different C-H Bonds

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Chinese Journal of Chemistry 2022年第7期40卷 838-845页

作者： chao-jun li Department of Chemistry FQRNT Centre for Green Chemistry and CatalysisMcGill University801 Sherbrooke Street W.MontrealQuebecH3A0B8 Canada

Constructing C-C bonds is central to the synthesis of all chemical *** conventional C-C bond formation methods always require one or two functional groups,20 years ago,our establishment of the concept of Cross-Dehydrogenative Coupling(CDC),wherein C-C bonds are directly formed from two different C-H bonds via the"formal"removal of two H atoms,has revolutionized chemical synthesis and has become one of the most active research subjects in *** perspective article will provide an insight of the origin of this concept and its early development in our laboratory.

关键词： Cross-Dehydrogenative Coupling(CDC) C-H activation Cross-coupling C-C bond formation Green chemistry

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A Cu/Cinchona P,N-ligand system enabled general asymmetric C(sp^3)–C(sp) coupling

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Science China Chemistry 2020年第6期63卷 751-752页

作者： Xianwei li chao-jun li Department of Chemistry and FQRNT Center for Green Chemistry and Catalysis McGill University801 Sherbrooke St.W.MontrealQuebec H3A 0B8Canada School of Chemical Engineering and light Industry Guangdong University of TechnologyGuangzhou 510006China

Due to the special structural feature and versatile reactivity towards various types of transformations,alkynes have inspired continuous research interest for their generation,incorporation and application in organic synthesis,chemical biology and material science[1].Notably,since its invention in 1975,the Sonogashira reaction,which efficiently couples aryl halides with aryl or vinyl terminal alkynes via Pd(0)/Cu(I)synergistic catalysis.

关键词： A Cu/Cinchona P,N-ligand system enabled general asymmetric C coupling

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Cleavage/cross-coupling strategy for converting β-O-4 linkage lignin model compounds into high valued benzyl amines via dual C–O bond cleavage

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Chinese Chemical Letters 2022年第3期33卷 1519-1523页

作者： Le Jia chao-jun li Huiying Zeng The State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000China Department of Chemistry FQRNT Centre for Green Chemistry and CatalysisMcGill UniversityMontrealQuebec H3A 0B8Canada

lignin is the most recalcitrant of the three components of lignocellulosic biomass. The strength and stability of the linkages have long been a great challenge for the degradation and valorization of lignin biomass to obtain bio-fuels and commercial chemicals. Up to now, the selective cleavage of C–O linkages of lignin to afford chemicals contains only C, H and O atoms. Our group has developed a cleavage/crosscoupling strategy for converting 4-O-5 linkage lignin model compounds into high value-added compounds. Herein, we present a palladium-catalyzed cleavage/cross-coupling of the β-O-4 lignin model compounds with amines via dual C–O bond cleavage for the preparation of benzyl amine compounds and phenols.

关键词： β-O-4 linkage lignin C-O bond cleavage Cross-coupling reaction Palladium-catalyzed

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Iodomethane as an organocatalyst for the aerobic ortho-selective trifluoromethylation of pyridines

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Science China Chemistry 2023年第1期66卷 133-138页

作者： Jianjin Yu Renqin Zhan chao-jun li Huiying Zeng State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou University.Lanzhou 730000China Department of Chemistry FQRNT Centre for Green Chemistry and CatalysisMcGll UniversityMontrealOuebec H3A OB8Canada

Iodomethane is usually used as an electrophilic methylation ***,we report its use as a C1 organocatalyst for the aerobic ortho-selective trifluoromethylation of pyridines in the absence of a transition *** acid(TFA)was employed as an inexpensive,readily available trifluoromethyl *** reaction efficiently produced a variety of trifluoromethylation products,with good functional group ***-containing drug molecules could also be selectively trifluoromethylated for late-stage *** studies showed that iodomethane selectively reacted with the pyridine starting material,rather than the pyridine product,to generate the corresponding N-methylpyridinium *** decarboxylation of trifluoroacetic acid produced a trifluoromethyl anion,which added to the methylpyridinium iodide,and the subsequent aerobic rearomatization led to the generation of the ortho-trifluoromethylated product.

关键词： iodomethane-catalysis trifluoromethylation pyridines transition-metal-free trifluoroacetic acid

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Model tests on interaction between soil and geosynthetics subjected to localized subsidence in landfills

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第6期13卷 433-444页

作者： Bin ZHU Deng GAO jun-chao li Yun-min CHEN MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Department of Civil EngineeringZhejiang UniversityHangzhou 310058China

In a landfill, excessive tensile strains or failure of the liner system due to localized subsidence underneath the geosynthetic liner, is a concern in design and operation of the landfill. The localized subsidence can be commonly withstood by reinforcements such as geogrids. A total of nine model tests were carried out to study the influence of soil arching in overburden sandy soil on the geosynthetics and the interaction between the soil and the geosynthetics. The localized subsidence was modeled by a strip trapdoor under the geosynthetic reinforcements. The reinforcement includes several layers of polyvinylchlorid （PVC） membrane or both PVC membrane and a compacted clay layer. Test results show that the vertical soil pressure acting on the geosynthetics within the subsidence zone is strongly related to the deflection of the geosynthefics. The soil pressure acting on the deflected geosynthetics will decrease to a minimum value with respect to its deflection if the final deflection is large enough, and this minimum value is almost independent of the overburden height. Otherwise, the deflection of geosynthetics cannot result in a full degree of soil arching, and the soil pressure within the subsidence zone increases with the increase of overburden height. Deflections and strains of the geosynthetics obviously decrease with the increase of their tensile stiffness. The presence of a compacted clay layer buffer can therefore reduce both deflections and strains of the geosynthetics. Finally, a composite liner structure is recommended for landfills to withstand the localized subsidences.

关键词： Landfill Soil arching Trapdoor Model test Geosynthetics

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Perspectives on green synthesis and catalysis

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Green Synthesis and Catalysis 2020年第1期1卷 1-11页

作者： Yiram Kim chao-jun li Department of Chemistry and FQRNT Center for Green Chemistry and Catalysis MontrealQC H3A0B8Canada

Despite their impressive capacity to access diverse functional groups and to synthesize structurally complex molecules,the majority of the organic reactions suffers from harsh conditions,low atom economy,and hazardous waste *** goal of our research is geared towards developing efficient methods to minimize the adverse environmental impact and contributing to chemical ***,we illustrate three distinct green approaches,studying the novel reactivities with environmentally innocuous reagents to improve the synthetic efficiency,utilization of natural feedstocks,and employment of green energy to facilitate various important chemical *** this perspective article,we hope to provide an overview of green synthetic chemistry and inspire the expansion of the field in the future.

关键词： Green chemistry Green synthesis and catalysis Aqueous reactions CDC reactions Natural feedstocks Photochemistry Electrochemistry

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Ru(Ⅱ)-catalyzed ortho-amidation and decarboxylation of aromatic acids: a versatile route to meta-substituted N-aryl benzamides

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Science China Chemistry 2015年第8期58卷 1286-1291页

作者： Xian-Ying Shi Xue-Fen Dong Juan Fan Ke-Yan liu jun-Fa Wei chao-jun li Key Laboratory of Applied Surface and Colloid Chemistry (Ministry of Education) Key Laboratory for Macromolecular Science of Shaanxi Province School of Chemistry and Chemical Engineering Shaanxi Normal University Department of Chemistry McGill University

Carboxylate as a promising and valuable directing group has attracted a great deal of ***,employing it as a traceless direction group has rarely been *** developed the ruthenium-catalyzed amidation of substituted benzoic acids with isocyanates via directed C–H functionalization followed by decarboxylation to afford the corresponding metasubstituted N-aryl benzamides,in which the carboxylate serves as a unique,removable directing ***,this protocol can provide an efficient alternative to access meta-substituted N-aryl benzamides,which are much more difficult to prepare than ortho-substituted analogues.

关键词： amides decarboxylation amidation C-H functionalization homogeneous catalysis

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One-pot synthesis of toluene from methane and methanol catalyzed by GaN nanowire

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Nano Research 2023年第5期16卷 6512-6516页

作者： Mingxin liu Zewen Wu Xianghua Kong Xu Zhang lida Tan Hong Guo chao-jun li State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou University222 Tianshui South RoadChengguan DistrictLanzhou 730000China Department of Chemistry FRQNT Centre for Green Chemistry and CatalystsMcGill University801 Sherbrooke WestMontrealQCH3A 0B8Canada College of Physics and Optoelectronic Engineering Shenzhen University3688 Nanhai AvenueNanshan DistrictShenzhen 518061China Department of Physics McGill UniversityRutherford Building3600 UniversityMontrealQCH3A 2T8Canada

The generation of aromatic benzene,toluene,xylene(BTX)compounds from non-petroleum feedstocks is of particular interest for chemists in the eyes of ***,a novel synthesis of toluene catalyzed by GaN semiconductor nanowire arrays is *** methane and methanol as starting materials,the GaN nanowire arrays can synergistically facilitate the facile generation of toluene under either photo-irradiation or *** detailed computational studies unveiled different mechanisms involved for the photo-and thermal-toluene synthesis.

关键词： GaN nanowire photocatalysis benzene toluene xylene(BTX)compounds renewable feedstock

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Transferable adversarial slow feature extraction network for few-shot quality prediction in coal-to-ethylene glycol process

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Chinese Journal of Chemical Engineering 2024年第7期71卷 258-271页

作者： Cheng Yang chao Jiang Guo Yu jun li Cuimei Bo School of Electrical Engineering and Control Science Nanjing Tech UniversityNanjing 211816China Department of Intelligent Manufacturing Nanjing Tech UniversityNanjing 210009China

In the coal-to-ethylene glycol(CTEG)process,precisely estimating quality variables is crucial for process monitoring,optimization,and control.A significant challenge in this regard is relying on offline laboratory analysis to obtain these variables,which often incurs substantial monetary costs and significant time *** resulting few-shot learning scenarios present a hurdle to the efficient development of predictive *** address this issue,our study introduces the transferable adversarial slow feature extraction network(TASF-Net),an innovative approach designed specifically for few-shot quality prediction in the CTEG ***-Net uniquely integrates the slowness principle with a deep Bayesian framework,effectively capturing the nonlinear and inertial characteristics of the CTEG ***,the model employs a variable attention mechanism to identify quality-related input variables adaptively at each time step.A key strength of TASF-Net lies in its ability to navigate the complex measurement noise,outliers,and system interference typical in CTEG *** learning strategy using a min-max game is adopted to improve its robustness and ability to model irregular industrial data accurately and ***,an incremental refining transfer learning framework is designed to further improve few-shot prediction performance achieved by transferring knowledge from the pretrained model on the source domain to the target *** effectiveness and superiority of TASF-Net have been empirically validated using a real-world CTEG *** with some state-of-the-art methods,TASF-Net demonstrates exceptional capability in addressing the intricate challenges for few-shot quality prediction in the CTEG process.

关键词： Chemical process Neural networks Slowness principle Transfer learning Prediction

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