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γ Radiative Decays to Light Quark Jets and Color Octet Mechanism

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Communications in Theoretical Physics 2006年第6X期46卷 1017-1022页

作者： gao ying-jia ZHANG Yu-Jie CHAO Kuang-Ta Department of Physics Peking Universlty Beijlng 100871 China China Center of Advanced Science and Technology (World Laboratory) Beijing 100080 China

We study radiative decays of T to light quark jets in nonrelativistic QCD by taking both the color singlet and color octet b^-b operators into consideration. The cut for quark jet energy and cut for the angle between two quark jets are introduced. The sensitivity to the soft and collinear singularities in the loop integrals are greatly reduced by these cuts. With the jet energy cut of about 1 GeV, and the jet angle cut of about 36°, the branching ratio for γ→ rq^- is found to be 8.2 × 10^-4 from color singlet contributions. The color octet contributions could be much larger than that of color singlet, depending on the estimate of the color octet matrix elements. This process may provide a new test for the color octet mechanism in nonrelativistic QCD.

关键词： radiative decay jet color octet

Photopromoted methoxycarbonylation of olefin with methyl formate by Co(OAc)2

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Chinese Chemical Letters 2007年第1期18卷 17-20页

作者： ying Na Cui Jing Mei Yin Da Bin gao ying Ping jia Guang Yun Zhou Shen Min Li Liaoning Key Laboratory of Bio-Organic Chemistry Dalian University Dalian 116622 China

The photopromoted methoxycarbonylation of olefin with methyl formate catalyzed by Co（OAc）2 at ambient conditions has been carried out. The results indicated that the reaction activity increased with the increasing temperature. Methyl formate decomposed into CO and CH3OH firstly under irradiation, and then the methoxycarbonylation of olefin proceeded under catalysis of Co（OAc）2. The mechanism of methyl formate participating in the methoxycarbonylation is verified by the IR analysis and the labeling experiments of CDHOD and CH3^18OH.

关键词： Mcthoxycarbonylation Methyl formate Olefin Photopromoted Cobalt acetate

Photopromoted carbonylation of 1-bromo-6-chlorohexane under ambient conditions

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Chinese Chemical Letters 2008年第5期19卷 529-532页

作者： Yao Yun Hu Jing Mei Yin Da Bin gao ying Ping jia Guang Yun Zhou ying Na Cui Shen Min Li Liaoning Key Laboratory of Bio-organic Chemistry Dalian University Dalian 116622 China

Photopromoted carbonylation of 1-bromo-6-chlorohexane with CO catalyzed by CuBr2 and CdI2 has been carried out under ambient conditions. The results indicate that the carbonylation proceeds with the major product of chloroester ClCH2（CH2）5COOCH3 under catalysis of CuBr2. Furthermore, the activity of the carbonylation can be improved by addition of basic additives （NaOAc, Na3PO4 or （n-C4H9）3N）. Among these additives, （n-C4H9）3N is the most efficient in terms of the yield of ClCH2（CH2）5COOCH3. However, the methoxycarbonyl substituting chlorine product of BrCH2（CH2）5COOCH3 is not obtained in the presence of CdI2. This is quite different from the carbonylation of monochloroalkane.

关键词： Photopromoted carbonylation 1-Bromo-6-chlorohexane Copper bromide Tri-n-butylamine

Glucose-sensitive Membrane with PBA-based Contraction-type Linear Polymer as Chemical Valves Prepared by Surface Grafting

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Chinese Journal of Polymer Science 2024年第8期42卷 1067-1076页

作者： Chun-Peng Zhang Si-jia gao ying Luo Lei Zou Yong-Jun Zhang State Key Laboratory of Separation Membranes and Membrane Processes School of Material Science and EngineeringTiangong UniversityTianjin 300387China State Key Laboratory of Separation Membranes and Membrane Processes School of Pharmaceutical SciencesTiangong UniversityTianjin 300387China Tianjin Key Laboratory of Extracorporeal Life Support for Critical Diseases Institute of Hepatobiliary DiseaseNankai University Affiliated Third Center HospitalTianjin 300170China Cangzhou Institute of Tiangong University Cangzhou 061000China

Glucose-sensitive membrane has potential application in self-regulating insulin *** acid(PBA)is a well-known glucose ***,most PBA-based glucose-sensitive materials are expansion-type,which are not suitable as chemical valves in membrane pores for self-regulating insulin *** to a new glucose-sensitive mechanism,we synthesized PBA-based contraction-type glucose-sensitive liner polymer and ***,a glucose-sensitive membrane was prepared by grafting PBA-based contraction-type glucose-sensitive linear polymer on the membrane *** adjusting the chain length and chain density,the glucose-sensitivity of the membrane was *** membrane can reversibly regulate insulin release at physiologically relevant glucose concentrations in simulates body fluids and fetal bovine *** membrane also has good stability,anti-fouling and biocom *** has potential application in selfregulating insulin release.

关键词： Phenylboronic acid Glucose-sensitive Membrane Surface grafting Insulin

Segmental nature of the Red River fault revealed by seismic anisotropy and geological structures

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Science China Earth Sciences 2024年第8期67卷 2423-2443页

作者： ying LI Yuan gao School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Key Laboratory of Earthquake Prediction Institute of Earthquake ForecastingChina Earthquake AdministrationBeijing 100036China

As the western boundary of the Sichuan-Yunnan block(SYB),the Red River fault(RRF)is a major fault that controls deep crustal movement and deformation in the southeast margin of the Tibetan Plateau and regulates middle-lower crustal *** data suggest that the RRF is segmented and exhibits distinct variations in seismicity,velocity structure and crustal deformation from north to *** anisotropy reveals a complex pattern of lateral spatial and vertical stratified distributions.(1)From the perspective of crustal stratification,in the upper crust,the fast wave polarization in the north segment of the RRF is complex and possibly influenced by the Sanjiang lateral collision zone and adjacent faults with varying *** fast wave polarization in the middle segment is in the NW-SE direction,indicating a localized area of closed down or locked up with consistent *** in the south segment,it presents a disordered pattern,signifying complex deep tectonics and stress conditions at the wedged intersection *** the middle-lower crust in the north and south segments of the RRF,the azimuthal anisotropy is strong and consistent with the spatial strike of the weak zone characterized by low-velocity and *** suggests a connection between the anisotropy and the material migration.(2)In the whole crustal scale,the fast wave directions in two sides of the RRF are consistent with the NW-SE tectonic *** indicates that the RRF,as a large fault potentially cutting through the whole crust,strongly controls the surrounding media.(3)In the lithospheric scale,the fast wave polarizations are oriented nearly E-W and independent of the fault strike,consistent with the low P-and S-wave velocity structures and positive radial anisotropy in the upper *** fast wave directions could be related to lithospheric olivine deformation and asthenospheric *** paper suggests a decoupling of deformation between the crust and the lithospheri

关键词： Red River fault Seismic anisotropy Geological structures Lithosphere Fault segmentation

Voluntary wheel running ameliorated the deleterious effects of high-fat diet on glucose metabolism,gut microbiota and microbial-associated metabolites

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Food Science and Human Wellness 2024年第3期13卷 1672-1684页

作者： Ling Zhang Wenyu Zou Yongyan Hu Honghua Wu ying gao Junqing Zhang jia Zheng Department of Endocrinology Peking University First HospitalBeijing 100034China Laboratory Animal Facility Peking University First HospitalBeijing 100034China

Exercise training is critical for the early prevention and treatment of obesity and diabetes ***,the mechanism with gut microbiota and fecal metabolites underlying the effects of voluntary wheel running on high-fat diet induced abnormal glucose metabolism has not been fully elaborated.C57BL/6 male mice were randomly assigned to 4 groups according to diets(fed with normal chow diet or high-fat diet)and running paradigm(housed in static cage or with voluntary running wheel).An integrative 16S rDNA sequencing and metabolites profiling was synchronously performed to characterize the effects of voluntary wheel running on gut microbiota and *** showed that voluntary wheel running prevented the detrimental effects of high-fat feeding on glucose metabolism 16S rDNA sequencing showed remarkable changes in Rikenella and Marvinbryantia *** profiling indicated multiple altered metabolites,which were enriched in secondary bile acid biosynthesis *** conclusion,our study indicated that voluntary wheel running significantly improved glucose metabolism and counteracted the deleterious effects of high-fat feeding on body weight and glucose *** further found that voluntary wheel running could integratively program gut microbiota composition and fecal metabolites changes,and may regulate muricholic acid metabolism and secondary bile acid biosynthesis in high-fat fed mice.

关键词： High-fat diet Voluntary wheel running Gut microbiota Metabolomics Glucose metabolism

New method for multibody dynamics based on unknown constraint force

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Science China(Technological Sciences) 2024年第3期67卷 791-808页

作者： TIAN ying jia yingHong ZHANG Jun School of Astronautics Beihang UniversityBeijing 100191China Beijing Institute of Control Engineering Beijing 100190China National Laboratory of Space Intelligent Control Beijing 100190China

This paper presents a new method for the dynamics of multibody systems based on unknown constraint force. The method can uniformly solve multibody systems with typical configurations, including the system with rigid-flexible coupling, the system in tree topology, and the system with loop constraints. Unlike common methods, the proposed method can model the loop system without “cutting off” loop constraints, leading to the exact same modelling process as the tree-like system performs. Based on graph theory, a topological record matrix M_(rec) is proposed to capture the arbitrary system configuration. Moreover, constraint forces are selected as the key variables in semi-recursive framework. With the recursive kinematics relationship between adjacent bodies, the constraint force equation is further assembled to achieve the full-state system solution. The numerical simulations demonstrate the accuracy of the proposed method.

关键词： multibody system dynamic modelling rigid-flexible coupling unknown constraint force graph theory semi-recursive algorithm

Universal origin of glassy relaxation as recognized by configuration pattern matching

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National Science Review 2024年第5期11卷 343-351页

作者： Hai-Bin Yu Liang gao jia-Qi gao Konrad Samwer Wuhan National High Magnetic Field Center and School of Physics Huazhong University of Science and Technology I.Physikalisches Institut Universit?t G?ttingen

Relaxation processes are crucial for understanding the structural rearrangements of liquids and amorphous materials. However, the overarching principle that governs these processes across vastly different materials remains an open question. Substantial analysis has been carried out based on the motions of individual particles. Here, as an alternative, we propose viewing the global configuration as a single entity. We introduce a global order parameter, namely the inherent structure minimal displacement(IS Dmin), to quantify the variability of configurations by a pattern-matching technique. Through atomic simulations of seven model glass-forming liquids, we unify the influences of temperature, pressure and perturbation time on the relaxation dissipation, via a scaling law between the mechanical damping factor and IS Dmin. Fundamentally,this scaling reflects the curvature of the local potential energy landscape. Our findings uncover a universal origin of glassy relaxation and offer an alternative approach to studying disordered systems.

关键词： glass transition metallic glass relaxation dynamics mechanical spectroscopy internal friction

Pathogen-induced methylglyoxal negatively regulates rice bacterial blight resistance by inhibiting OsCDR1 protease activity

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Molecular Plant 2024年第2期17卷 325-341页

作者： Zheng-Wei Fu jian-Hui Li Xiang gao Shi-jia Wang Ting-Ting Yuan ying-Tang Lu State Key Laboratory of Hybrid Rice College of Life SciencesRenmin Hospital of Wuhan UniversityWuhan UniversityWuhan 430072China Key Laboratory of Biology and Genetic Improvement of OilCrops Ministry of Agriculture and Rural AffairsOilCrops Research Institute of the Chinese Academy of Agricultural SciencesWuhan 430062China

Xanthomonas oryzae ***(Xoo)causes bacterial blight(BB),a globally devastating disease of rice(Oryza sativa)that is responsible for significant crop *** and sugar metabolites are important for pathogen infection,providing energy and regulating events associated with defense responses;howev-er,the mechanisms by which they regulate such events in BB are *** an inevitable sugar metabolite,methylglyoxal(MG)is involved in plant growth and responses to various abiotic stresses,but the underlying mechanisms remain *** and how MG functions in plant biotic stress responses is almost completely ***,we report that the Xoo strain PXO99 induces OsWRKY62.1 to repress transcrip-tion of OsGLY Il genes by directly binding to their promoters,resulting in overaccumulation of *** negatively regulates rice resistance against Pxo99:osglyll2 mutants with higher MG levels are more sus-ceptible to the pathogen,whereas OsGLYIl2-overexpressing plants with lower MG content show greater resistance than the wild *** of OsGLYll2 to prevent excessive MG accumulation confers broad-spectrum resistance against the biotrophic bacterial pathogens Xoo and Xanthomonas oryzae *** and the necrotrophic fungal pathogen Rhizoctonia solani,which causes rice sheath *** evidence shows that MG reduces rice resistance against PXO99 through CONSTITUTIVE DISEASE RESISTANCE 1(OsCDR1).MGmodifies the Arg97 residue of OsCDR1to inhibit its aspartic protease activ-ity,which is essential for OsCDR1-enhanced *** together,these findings illustrate how Xoo promotes infection by hijacking a sugar metabolite in the host plant.

关键词： Oryza sativa bacterial blight OsWRKY62.1 methylglyoxal OsCDR1