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International Journal of Minerals,Metallurgy and Materials 2010年第3期17卷 347-352页

作者： yan liu shi-xiang liu ming-wen wang wen-jun li ting zhang xia zhang School of Applied Science University of Science and Technology Beijing Beijing 100083 China

A novel red long-lasting phosphor, （YxGd1-x）2O3：Eu3＋, Sm3＋, Si4＋, Mg2＋, was synthesized by the co-precipitation method using oxalate precipitation as the precursor. X-ray diffraction （XRD）, scanning electronic microscopy （SEM）, integrated thermal analyzer （TG）, and photoluminescence spectra （PL） as well as the ST-900PM weak light photometer were used to study the synthesis conditions, morphology, luminescence properties, and the decay time of the phosphor. The XRD results show that the products synthesized at 1400~C for 4 h have good crystallization without any detectable impurity phases. Based on the PL spectra, the optimal conditions are as the following. The molar ratios of Y3＋ to Gd3＋ and Eu3＋ to Sm3＋ are 2：8 and 3：1, respectively, and the contents of Mg2＋ and SiO2 are 5mol% and 3mol%, respectively. The decay time monitored by the ST-900PM weak light photometer is 7200 s, increasing 44% and 100%, respectively, compared with the Eu3＋ and Sm3＋ single-doped phosphors. The results indicate that the energy transfer is from Sm3＋ to Eu3＋ ion, and Sm3＋ is a good sensitizer to Eu3＋.

关键词： long lasting phosphor luminescence energy transfer

多光谱法研究二氢杨梅素对胰脂肪酶的抑制作用

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光谱学与光谱分析 2025年第1期45卷 107-116页

作者：孟晓慧黄旭波夏张晨徐娟王衍彬程俊文杨柳贺亮浙江省森林资源生物与化学利用重点实验室浙江省林业科学研究院浙江杭州310023 浙江省特色中药资源保护与创新利用重点实验室浙江农林大学食品与健康学院浙江杭州311300

藤茶中主要黄酮类物质——二氢杨梅素(DMY)具有多种生物活性,而其降血脂机理鲜有报道。采用紫外光谱研究了DMY对胰脂肪酶(PL)的抑制作用,结合荧光光谱、同步荧光光谱、三维荧光光谱及分子对接模拟法研究了二者之间的相互作用及机理。紫... 详细信息

藤茶中主要黄酮类物质——二氢杨梅素(DMY)具有多种生物活性,而其降血脂机理鲜有报道。采用紫外光谱研究了DMY对胰脂肪酶(PL)的抑制作用,结合荧光光谱、同步荧光光谱、三维荧光光谱及分子对接模拟法研究了二者之间的相互作用及机理。紫外光谱测得DMY对PL的半抑制浓度为2.6×10^(-4)mol·L^(-1),表明其对PL具有较好的抑制作用,采用lineweaver-Burk方程得出该抑制剂为竞争性作用,其抑制常数为6×10^(-4)mol·L^(-1);通过Stern-Volmer方程和静态猝灭双对数公式对293和310 K两者互作的荧光光谱计算,结果表明DMY能猝灭PL的自发荧光,荧光猝灭方式为静态猝灭,猝灭常数K_(SV)与温度负相关;结合常数K a与温度正相关,结合位点数n约为1,说明DMY与PL结合并形成稳定的配位复合物;采用Van't Hoff方程求出结合过程中的热力学参数ΔS=0.2014 J·mol^(-1)·K^(-1),ΔH=32.311 kJ·mol^(-1),ΔG小于0,表明两者通过疏水作用力自发结合且放热;由F rster非辐射能量转移理论计算出结合距离r=1.475 nm,说明DMY与PL结合生成复合物时发生了非辐射能量转移;同步荧光光谱结果表明,DMY与PL的相互作用对PL的二级构象发生了明显改变,主要作用于色氨酸(Tyr)附近。紫外光谱进一步揭示DMY可使PL发生π→π跃迁,导致其氨基酸残基的微环境变化;三维荧光光谱显示DMY可使PL两个特征峰(peak1,peak2)分别红移10和5 nm,荧光强度分别下降51.38%和41.93%,证实两者发生疏水作用后PL的微环境极性增大,构象改变;分子对接模拟结果表明,DMY结合位点位于PL中由PHE77、PHE215、TYR114、ILE209、PRO180氨基酸形成的疏水口袋内,其A环C5、B环C4′、C环C3、C环C O的-OH分别与氨基酸HIS263、TYR114、SER152、PHE215形成氢键,与氨基酸LRU213、GLU179、ALA178、THR78产生范德华力。实验数据有助于深入解DMY的降血脂分子作用机制,其独特的结构为天然抑制剂的药物合成和筛选提供了理论依据。

关键词：二氢杨梅素胰脂肪酶多光谱法分子对接模拟

Epigenetics in the modern era of crop improvements

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Science China life Sciences 2025年

作者： yan Xue xiaofeng Cao xiangsong Chen xian Deng Xingwang Deng Yong Ding Aiwu Dong Chengguo Duan xiaofeng Fang Lei Gong Zhizhong Gong xiaofeng Gu Chongsheng He Hang He Shengbo He Xinjian He yan He Yuehui He Guifang Jia Danhua Jiang Jianjun Jiang Jinsheng Lai Zhaobo Lang Chenlong li Qing li Xingwang li Bao liu Bing liu xiao Luo Yijun Qi Weiqiang Qian Guodong Ren Qingxin Song xianwei Song Zhixi Tian Jiawei wang Yuan wang liang Wu Zhe Wu Rui xia jun xiao lin Xu Zhengyi Xu wenhao yan Hongchun yang Jixian Zhai Yijing zhang Yusheng Zhao Xuehua Zhong Daoxiu Zhou ming Zhou Yue Zhou Bo Zhu Jiankang Zhu Qikun liu College of life Sciences Institute of Life Science and Green Development Hebei University Biotechnology Research Institute Chinese Academy of Agricultural Sciences College of Biology Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation Hunan Engineering and Technology Research Center of Hybrid Rapeseed Hunan University Institute of Advanced Agricultural Sciences School of Advanced Agricultural Sciences Peking University State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources Guangdong Laboratory for Lingnan Modern Agriculture South China Agricultural University National Institute of Biological Sciences Key Laboratory of Seed Innovation Institute of Genetics and Developmental Biology Chinese Academy of Sciences School of Advanced Agricultural Sciences Peking-Tsinghua Center for Life Sciences Peking University Synthetic and Functional Biomolecules Center Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of Chemistry and Molecular Engineering Peking University Key Laboratory of Seed Innovation State Key Laboratory of Plant Genomics and National Center for Plant Gene Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences State Key Laboratory of Wheat Improvement Peking University Institute of Advanced Agricultural Sciences Shandong Laboratory of Advanced Agricultural Sciences in Weifang State Key Laboratory of Crop Stress Adaptation and Improvement School of Life Sciences Henan University State Key Laboratory of Maize Bio-breeding National Maize Improvement Center Department of Plant Genetics and Breeding China Agricultural University Frontiers Science Center for Molecular Design Breeding China Agricultural University Center for Crop Functional Genomics and Molecular Breeding China Agricultural University Sanya Institute of China Agricultural University Hainan Yazhou Bay Seed Laboratory Institute of Advan

Epigenetic mechanisms are integral to plant growth, development, and adaptation to environmental stimuli. Over the past two decades,our comprehension of these complex regulatory processes has expanded remarkably, producing a substantial body of knowledge on both locus-specific mechanisms and genome-wide regulatory patterns. Studies initially grounded in the model plant Arabidopsis have been broadened to encompass a diverse array of crop species, revealing the multifaceted roles of epigenetics in physiological and agronomic traits. With recent technological advancements, epigenetic regulations at the single-cell level and at the large-scale population level are emerging as new focuses. This review offers an in-depth synthesis of the diverse epigenetic regulations, detailing the catalytic machinery and regulatory functions. It delves into the intricate interplay among various epigenetic elements and their collective influence on the modulation of crop traits. Furthermore, it examines recent breakthroughs in technologies for epigenetic modifications and their integration into strategies for crop improvement. The review underscores the transformative potential of epigenetic strategies in bolstering crop performance, advocating for the development of efficient tools to fully exploit the agricultural benefits of epigenetic insights.

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Vapour-phase O-methylation of Catechol with Methanol on Ti-containing Phosphate Catalysts

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Chemical Research in Chinese Universities 2006年第4期22卷 533-536页

作者： ZHU xiao-mei li Xue-mei liu Gang ZOU Xiu-jing wang yan-li JIA ming-jun zhang wen-xiang College of Chemistry Jilin University Changchun 130021 P. R. China Shanghai Huayi Acrylic Acid Co. Ltd. Shanghai 200137 P. R. China

Ti-containing phosphate（ Ti-P-O ） catalysts with different molar ratios of P to Ti （0--2. 0 ） were synthesized and characterized by XRD, N2-adsorption/desorption, IR and temperature-programmed desorption （TPD） methods. The catalytic properties of Ti-P-O samples in the vapor-phase O-methylation of catechol with methanol were also studied. The catechol conversion increases with the increase of the molar ratio of P to Ti in a range of 0-0. 33, while a further increase in the P content leads to a decrease of the catalytic activity. Meanwhile, the selectivities of the catalysts to the main product（guaiacol） increase gradually with the increase of the molar ratio of P to Ti. The presence of relatively strong Lewis acidic and/or basic sites in the P-free catalyst should be responsible for the formation of C-alkylation products. The weak acid-base characteristics of the catalysts are favourable for the mono-O-methylation of catechol. In comparison with the Lewis acidic sites, the Bronsted acidic sites on the catalysts are more active for the title reaction.

关键词： Phosphates Acid-base catalysis Guaiacol Catechol O-Methylation

Comparison of gene expression of the oncogenic Wnt/β-catenin signaling pathway components in the mouse and human epididymis

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Asian Journal of Andrology 2015年第6期17卷 1006-1011,I0011页

作者： Kai wang Ning li Ching-Hei Yeung Trevor G Cooper Xue-xia liu Juan liu wen-ting wang yan li Hui shi Fu-jun liu School of Agriculture Ludong University Yantai Shandong China Central Laboratory Yantai Yuhuangding Hospital Yantai Shandong China College of life Science Yantai University Yantai Shandong China

β-catenin is an integral part of the Wnt signaling pathway and has been linked to tumorigenesis and multiple developmental processes. The high β-catenin expression with low tumor incidence in the human epididymis is thus intriguing. In the present study, the β-catenin gene and protein was found to be highly expressed in the murine caput epididymidis, and the protein mainly localized along the lateral plasma membranes of adjacent epithelial cells throughout both human and mouse epididymides. Furthermore, the adult mouse epididymis was found to express almost all the Wnt/β-catenin signaling pathway genes that were determined previously by our group in the human organ. Despite the differences in epididymal structure, the similar location of β-catenin and the high concordance of this pathway＇s components＇ gene expression in both the adult human and mouse epididymides make the mouse a suitable animal model for studying the anti-tumor mechanism of the epididymis. In addition, both the mRNA and protein expression of β-catenin shared a similar spatial expression as the mRNA of Rosl, a proto-oncogene and a key developmental regulator of the initial segment of the mouse epididymis. The observations on the parallel temporal expression of β-catenin and Rosl during postnatal development raise the possibility that the canonical Writ signaling pathway has an additional role in the postnatal development of mouse epididymis.

关键词： epididymis postnatal development tumorigenesis Wnt/β-catenin pathway β-catenin

Analysis of the diversity and function of the alleles of the rice blast resistance genes Piz-t, Pita and Pik in 24 rice cultivars

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Journal of Integrative Agriculture 2016年第7期15卷 1423-1431页

作者： wang yan ZHAO Jia-ming zhang li-xia wang Ping wang shi-wei wang Hui wang xiao-xi liu Zhi-heng ZHENG wen-jing Plant Protection College Shenyang Agricultural University Agricultural Crops Molecular Improving Laboratory Liaoning Academy of Agricultural Sciences Department of Plant Pathology China Agricultural University

Understanding the sequence diversity of rice blast resistance genes is important for breeding new resistant rice cultivars against the rice blast fungusMagnaporthe oryzae. In this study, we selected 24 rice cultivars with different genetic back-grounds to study the alelic diversity of rice blast resistance genesPiz-t, Pitaand Pik. For Piz-t, a total of 17 alelic types were found within the 24 cultivars. Blast inoculations showed that most of the mutations can affect the function of the resistance gene. For Pita, except for the difference at the 918th amino acid, a majority of the 21 mutations were detected among the cultivars. Inoculations with blast isolates carryingAvr-Pita revealed that cultivars with mutations in other sites except for the 918th amino acid did not affect the function of thePita gene. ForPik, a total of six alelic types were found within the 24 cultivars, but ifve of them lost the function of the resistance gene. In addition, we found thatPiz-t, Pita and Pik were expressed constitutively in the 24 rice cultivars and the expression level was not related to resistance. Our results have provided the sequence diversity information of the resistance genesPiz-t, Pita and Pik among the popular rice cultivars grown in the northeast region of China. Keywords：resistance gene, avirulence gene, aleles, function, genetic evolution zae（M. oryzae）, is one of the most destructive diseases in rice production worldwide. Over the years, comprehensive studies on rice blast resistance have been conducted （Silue et al. 1992）. The resistance in newly cultivated rice cultivars to M. oryzae can be lost quickly due to the high level of instability in the genome of the fungus （Bonmanet al. 1992）. Previous studies show that cultivars with durable and broad-spectrum resistance againstM. oryzae carry multiple major resistance （R） and minor resistance genes （liuet al. 2014）. An effective way to control rice blast disease is, therefore, to breed rice cultivars with multiple R

关键词： resistance gene avirulence gene aleles function genetic evolution

Evolutionary-assisted reinforcement learning for reservoir real-time production optimization under uncertainty

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Petroleum Science 2023年第1期20卷 261-276页

作者： Zhong-Zheng wang Kai zhang Guo-Dong Chen Jin-Ding zhang wen-Dong wang Hao-Chen wang li-ming zhang xia yan jun Yao School of Petroleum Engineering China University of PetroleumQingdao266580ShandongChina Qingdao University of Technology Qingdao266520ShandongChina The University of Hong Kong 999077Hong KongChina

Production optimization has gained increasing attention from the smart oilfield community because it can increase economic benefits and oil recovery *** existing methods could produce high-optimality results,they cannot be applied to real-time optimization for large-scale reservoirs due to high computational *** addition,most methods generally assume that the reservoir model is deterministic and ignore the uncertainty of the subsurface environment,making the obtained scheme unreliable for practical *** this work,an efficient and robust method,namely evolutionaryassisted reinforcement learning(EARL),is proposed to achieve real-time production optimization under ***,the production optimization problem is modeled as a Markov decision process in which a reinforcement learning agent interacts with the reservoir simulator to train a control policy that maximizes the specified *** deal with the problems of brittle convergence properties and lack of efficient exploration strategies of reinforcement learning approaches,a population-based evolutionary algorithm is introduced to assist the training of agents,which provides diverse exploration experiences and promotes stability and robustness due to its inherent *** with prior methods that only optimize a solution for a particular scenario,the proposed approach trains a policy that can adapt to uncertain environments and make real-time decisions to cope with unknown *** trained policy,represented by a deep convolutional neural network,can adaptively adjust the well controls based on different reservoir *** results on two reservoir models show that the proposed approach not only outperforms the RL and EA methods in terms of optimization efficiency but also has strong robustness and real-time decision capacity.

关键词： Production optimization Deep reinforcement learning Evolutionary algorithm Real-time optimization Optimization under uncertainty

Investigation of factors affecting vertical sag of stretched wire

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Nuclear Science and Techniques 2021年第2期32卷 90-100页

作者： Jian-Dong Yuan jun-xia Wu Bin zhang Yuan He jun-Hui zhang wen-jun Chen Shao-ming wang Guo-Zhen Sun Xu-Dong zhang li-Song yan Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

To study vertical sag requirements and factors affecting the stretched wire alignment method,the vertical sag equation is first derived ***,the influencing factors(such as the hanging weight or tension,span length,temperature change,elastic deformation,and the Earth’s rotation)of the vertical sag are summarized,and their validity is verified through actual ***,the essential factors affecting vertical sag,i.e.,the specific strength and length,are *** is believed that the vertical sag of a stretched wire is proportional to the square of the length and inversely proportional to the specific strength of the material.

关键词： Stretched wire Alignment Vertical sag Catenary Hyperbolic cosine linear density Earth rotation

Effects of palm fat powder and coated folic acid on growth performance, ruminal fermentation, nutrient digestibility and hepatic fat accumulation of Holstein dairy bulls

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Journal of Integrative Agriculture 2020年第4期19卷 1074-1084页

作者： zhang Zhen liu Qiang wang Cong GUO Gang HUO wen-jie zhang yan-li PEI Cai-xia zhang Shuan-lin College of Animal Science and Veterinary Medicine Shanxi Agricultural UniversityTaigu 030801P.R.China

This study evaluated the effects of palm fat powder(PFP) and coated folic acid(CFA) on growth performance, ruminal fermentation, nutrient digestibility, microbial enzyme activity, microflora, hepatic lipid content and gene expression in dairy bulls. Forty-eight Chinese Holstein bulls((362±12.4) days of age and(483±27.1) kg of body weight(BW)) were assigned to four groups in a completely randomized design with a 2×2 factorial arrangements. Supplemental PFP(0 or 30 g PFP kg-1 dietary dry matter(DM)) and CFA(0 or 120 mg FA d-1 as CFA) were mixed into the top one-third of a total mixed ration. The study included a 20-day adaptation period and followed by a 90-day collection period. The lower(Plity, microbial α-amylase activity, Butyrivibrio fibrisolvens copy, and expression of peroxisome-proliferator-activated receptor α(PPARα) and carnitine palmitoyl transferase-1(CPT1), and lower ruminal total volatile fatty acids(VFA) concentration, acetate to propionate ratio, neutral detergent fibre(NDF) digestibility, copies of total protozoa and Ruminococcus flavefaciens, and expression of sterol regulatory element binding protein-1(SREBP1) and acetyl-coenzyme A carboxylase α(ACACA) were observed for PFP addition. Supplementation with CFA increased(Plity of DM, organic matter, crude protein and NDF, activity of cellobiase, pectinase and α-amylase, copies of selected microbial except for total protozoa, as well as expression of PPARα, but decreased(P<0.05) ruminal p H, and expression of SREBP1 and ACACA. The PFP×CFA interaction(P<0.05) was observed for ammonia N, hepatic TG content, and m RNA expression of CPT1 and FAS. There had no significant difference in hepatic TG content when CFA was supplemented in the diet with

关键词： palm fat powder coated folic acid growth performance gene expression dairy bulls

Emission Behaviors of Submicron Particles(PM_(1))Generated by the Combustion of Sesame Stalk after Combined Water Washing and Carbonization Pretreatment

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Energy Engineering 2021年第3期118卷 473-485页

作者： Tianyu liu Chang wen wenyu wang Kai yan Yongjun xia Rui li Juan liu yang zhang State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan430074China Department of New Energy Science and Engineering School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan430074China China-EU Institute for Clean and Renewable Energy Huazhong University of Science and TechnologyWuhan430074China State Grid Jiangxi Electric Power Science Research Institute Nanchang330096China

Pretreatment before biomass combustion is significant for its efficient utilization and that combined water washing and carbonization can be *** agricultural processing residues sesame stalk was selected and carried out two pretreatments separately,i.e.,water washing-torrefaction(W-T)and torrefaction-water washing(T-W),to explore the effect on the fuel properties,combustion characteristics and particulate matter(PM)*** obtained biochar was also combusted under air and oxy50(CO_(2):O_(2)=50:50)conditions for the sake of investigating the effect of pretreatment and combustion *** results indicate that,W-T and T-W both not only have great effect on the improvement of fuel properties but also reduce the content of water-soluble elements like K,Cl,*** to the difference in hydrophobicity,the biochar obtained by W-T have the optimal fuel *** the same time,the pretreatment also hinder the combustion in a certain extent in which the comprehensive combustion characteristics(SN)show a downward ***,both two pretreatments have obvious benefit on the reduction of PM_(1)emission and W-T have the best effect related to the higher removal efficiency of inorganic elements(especially K+Na+Cl+S).Under oxy50 condition,the oxygen concentration and combustion temperature is higher,improving the sulfation of K and vaporization of Ca,P and Mg which result in weakening in the pretreatment reduction effect on PM_(1)emission.

关键词： Biomass torrefaction water washing oxy-fuel PM_(1)