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Efficient Activity Enhancement of a Lipase from Sporisorium reilianum for the Synthesis of a Moxifloxacin Chiral Intermediate via Rational Design

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Engineering 2022年第12期19卷 207-216页

作者： Xue Cai Jiang-Wei Shen Yu Qiang Jing hua zhang-Qi Ma Zhi-Qiang Liu Yu-Guo Zheng The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals Zhejiang University of TechnologyHangzhou 310014China Key Laboratory of Bioorganic Synthesis of Zhejiang Province College of Biotechnology and BioengineeringZhejiang University of TechnologyHangzhou 310014China

Lipase-catalyzed stereoselective resolution of cis-(±)-dimethyl 1-acetylpiperidine-2,3-dicarboxylate(cis-(±)-1)is an attractive route for the synthesis of(S,S)-2,8-diazobicyclo[4.3.0]nonane,an important chiral intermediate of the fluoroquinolone antibiotic,*** our previous study,a lipase from Sporisorium reilianum(SRL)was identified to possess excellent thermostability and pH ***,the low enzymatic activity of the SRL is a challenge that must be addressed.A rational design was initially employed for SRL tailoring according to the engineered Candida antarctica lipase B(CALB),resulting in a beneficial variant called SRL-I194N/***,two key amino acid residues in loop 6,L145 and L154,which might modulate the lid conformation between open and closed,were identified.A tetra-site variant,SRL-I194N/V195L/L145V/L154G(V13),with a significantly enhanced activity of 87.8 U∙mg^(−1) was obtained;this value was 2195-fold higher than that of wild-type *** V13 was used to prepare optically pure(2S,3R)-dimethyl 1-acetylpiperidine-2,3-dicarboxylate((2S,3R)-1),resolving 1 mol∙L^(−1) cis-(±)-1 with a conversion of 49.9%in 2 h and absolute stereoselectivity(E>200).Excellent stability with a half-life of 92.5 h was also observed at 50℃.Overall,the study findings reveal a lipase with high activity toward cis-(±)-1 at an industrial level and may offer a general strategy for enhancing the enzyme activity of other lipases and other classes of enzymes with a lid moiety.

关键词： Lipase Sporisorium reilianum Site-directed mutagenesis Molecular dynamics simulation Rational design Moxifloxacin

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专业设计、用户设计还是ai设计?设计源效应的心理机制

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心理科学进展 2024年第6期32卷 995-1009页

作者：吴波张傲杰曹菲天津财经大学商学院天津300222

设计源效应是指企业产品设计来源信息对消费者产品偏好和企业态度的影响。目前,专业设计师、用户和ai是三种常见的产品设计源。这三种产品设计源通过不同的作用机制对消费者心理和行为产生积极或消极的影响。其中,能力是专业设计源效应... 详细信息

设计源效应是指企业产品设计来源信息对消费者产品偏好和企业态度的影响。目前,专业设计师、用户和ai是三种常见的产品设计源。这三种产品设计源通过不同的作用机制对消费者心理和行为产生积极或消极的影响。其中,能力是专业设计源效应产生的作用机制,能力、权力和心理距离是用户设计源效应产生的作用机制,而价值和信息是ai设计源效应产生的作用机制。同时,设计源效应是有作用条件的,会受到消费者、产品、企业因素的约束。未来研究可以深入探讨消费者对混合设计源的反应、进一步探讨设计源效应的作用机制和作用条件。

关键词：设计源效应产品设计沟通专业设计用户设计人工智能设计

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Geochronology and geochemistry of the Hekoulinchang Sn-Pb-Zn-Ag polymetallic deposit(73240 t) in Heilongjiang Province, China

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China Geology 2022年第1期5卷 46-59页

作者： Yong zhang Quan-heng Song Shi-jiong Han Jian-hua Ding Ministry of Natural Resources Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China Institute of Geological Survey of Jilin Province Changchun 130061China College of Earth Sciences Jilin UniversityChangchun 130061China

The Hekoulinchang Sn-Pb-Zn-Ag polymetallic deposit(20000 t Sn at 0.27%,236 t Ag at 122.89 g/t,15000 t Pb at 0.84%,and 38000 t Zn at 1.43%)is located in the Wandashan Terrane of the easternmost segment of the Central Asian Orogenic *** timing of Sn-Pb-Zn-Ag polymetallic mineralization remains unclear due to a lack of precise isotope dating directly conducted on ore *** authors herein report that the LA-ICP-MS U-Pb ages of cassiterite and zircon from the granite porphyry in the Hekoulinchang Sn-Pb-Zn-Ag polymetallic deposit are 101.4±7.9 Ma and 115.4±1.0 Ma,respectively,indicating that Sn mineralization and magmatism occurred during the Early *** granite porphyry belongs to the subalkaline series peraluminous I-type granites that are depleted in Nb,Ta,and Ti and enriched in Rb,Th,U,and ***εHf(t)values of the granite porphyry range from 0.9 to 7.4,with an average of about 5.6 and two-stage model ages(T_(DM2))of 705–1116 Ma,with an average age of 819 *** ε_(Nd)(t)values of the apatites are–1.60–0.45,with an average of–0.9,and two-stage model ages(T_(DM2))of 872–1040 Ma,with an average age of 983 *** Nd-Hf isotope data indicate that the magma may have been derived from the partial melting of juvenile crustal material.

关键词： Cassiterite U-Pb dating Zircon U-Pb dating Nd-Hf isotopes Porphyry Sn-Pb-Zn-Ag polymetallic deposit Hekoulinchang Heilongjiang Province Central Asian Orogenic Belt

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活性炭疏水/超疏水改性技术研究进展

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表面技术 2024年第5期53卷 1-17页

作者：庄怡凡刘星宇花颢轩苏一凡侯泽钟周张恒季延正焦玄余新泉张友法东南大学材料科学与工程学院南京211189 东南大学江苏省先进金属材料高技术研究重点实验室南京211189

活性炭具有丰富的孔隙结构和表面官能团,广泛用于吸附污染环境中的各种有机物。由于活性炭表面富含亲水官能团,在潮湿环境下将优先吸附水分子,从而大幅度降低了对目标有机物的吸附容量,因此如何改善活性炭的防潮防水性能是其应用过程中... 详细信息

活性炭具有丰富的孔隙结构和表面官能团,广泛用于吸附污染环境中的各种有机物。由于活性炭表面富含亲水官能团,在潮湿环境下将优先吸附水分子,从而大幅度降低了对目标有机物的吸附容量,因此如何改善活性炭的防潮防水性能是其应用过程中亟待解决的问题。大量研究表明,活性炭经疏水/超疏水改性后,可有效隔绝水汽,显著提高其防潮、防水性能,这种特殊性能使疏水/超疏水活性炭在诸多领域都有着极高的应用前景和市场价值。基于活性炭的吸附机理,从活性炭的物理结构和表面化学性质2个角度出发,概述了活性炭的来源和形貌,着重介绍了不同的疏水/超疏水改性技术,包括高温加热处理、负载金属氧化物、有机分子改性、有机硅涂层、有机无机复合超疏水涂层的改性制备方法及相应的优缺点,并在此基础上分析了不同改性技术对活性炭的防潮、防水能力及吸附目标有机物的影响。进一步讨论了疏水/超疏水活性炭在不同领域(例如废水处理、废气处理及电化学催化等)的实际应用效果,并指出了现有技术存在的局限性,最后对活性炭的发展进行了展望。

关键词：活性炭有机物吸附超疏水防潮防水

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不同基质配比对日光温室黄瓜根际基质环境及细菌群落结构的影响

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西南农业学报 2024年第6期37卷 1295-1303页

作者：李梅花周娟王彦丽党仕卓汤学燊胡豪张亚红宁夏大学葡萄酒与园艺学院银川750021

【目的】探究不同比例葡萄废弃枝条复配基质在黄瓜栽培过程中根际基质环境及细菌群落结构变化,为葡萄废弃枝条的基质化利用途径提供理论依据与技术支撑。【方法】以黄瓜为研究对象,测定5个处理[CK:商品基质、T1:v(葡萄枝条发酵物)∶v(草... 详细信息

【目的】探究不同比例葡萄废弃枝条复配基质在黄瓜栽培过程中根际基质环境及细菌群落结构变化,为葡萄废弃枝条的基质化利用途径提供理论依据与技术支撑。【方法】以黄瓜为研究对象,测定5个处理[CK:商品基质、T1:v(葡萄枝条发酵物)∶v(草炭)∶v(珍珠岩)=2∶5∶3、T2:v(葡萄枝条发酵物)∶v(草炭)∶v(珍珠岩)=3∶4∶3、T3:v(葡萄枝条发酵物)∶v(草炭)∶v(珍珠岩)=4∶3∶3、T4:v(葡萄枝条发酵物)∶v(草炭)∶v(珍珠岩)=5∶2∶3]的基质养分和酶活性特征,并利用Illumina MiSeq高通量测序技术探究各处理黄瓜根际基质细菌群落结构变化。【结果】葡萄废弃枝条复配基质养分与CK相比差异显著,复配基质速效氮、速效磷含量显著增加,碱性磷酸酶、脲酶、过氧化氢酶、纤维素酶活性均有明显提高。细菌群落组成结果显示,使用复配基质栽培的黄瓜根际细菌群落多样性与丰富度指数显著提高,T4处理增加最显著。不同处理细菌群落物种组成相同,但复配基质处理细菌群落结构较CK存在较大差异,结果表明,放线菌门、变形菌门、绿弯菌门、酸杆菌门为各处理共有优势菌门,占总丰度的75.27%~81.33%。相关性分析结果表明,影响细菌多样性的主要因素为速效氮、速效磷、速效钾。【结论】不同基质配比显著影响基质养分、细菌多样性与群落结构,其中T3、T4处理的基质养分特征、酶活性及细菌多样性与丰富度较优,可作为黄瓜栽培的最适基质配比。

关键词：葡萄废弃枝条复配基质基质养分酶活性细菌群落多样性

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基于知识追踪和知识网络的学生成绩预测

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计算机技术与发展 2024年第8期34卷 202-208页

作者：周铖郝国生张谢华杨晓菡祝义江苏师范大学计算机科学与技术学院江苏徐州221116 江苏思维驱动智能研究院有限公司江苏徐州221000

随着教育事业和数字技术的蓬勃发展,高校内大量学生学习数据开始以电子形式进行存储。预测学生在未来学习中的表现(如成绩)成为一个重要课题。在现有的学生成绩预测研究中,大多数忽略了学生历史习题之间隐含的关联性。因此,该文提出了... 详细信息

随着教育事业和数字技术的蓬勃发展,高校内大量学生学习数据开始以电子形式进行存储。预测学生在未来学习中的表现(如成绩)成为一个重要课题。在现有的学生成绩预测研究中,大多数忽略了学生历史习题之间隐含的关联性。因此,该文提出了基于知识追踪和知识网络的学生成绩预测方法,其主要思想是融合知识追踪和习题对应知识点的知识网络实现成绩预测。该方法将每个学生所做习题对应的知识点以及前驱知识点组成的知识网络作为输入之一,并在知识网络中标注出掌握程度大于给定阈值的知识点;结合LSTM神经网络,通过学生学习记录融合注意力机制来追踪学生知识水平,最终预测学生在未来做题中的表现。在公开数据集上的实验结果表明,该模型在Assistment2009数据集上较DKT、DKT+、DKVMN、SAKT、MFKT、MSKT分别提高了2.3%,2.2%,3.3%,3.4%,0.41%,2.0%,在Assistment2015数据集上分别提高了9.0%,9.4%,9.7%,9.3%,8.1%,8.5%,具有较好的模型精度。

关键词：知识追踪知识网络成绩预测注意力机制长短期记忆网络

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溶剂交换对水泥基材料微结构的影响

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硅酸盐学报 2023年第8期51卷 2098-2107页

作者：张爱葛勇哈尔滨工业大学交通科学与工程学院哈尔滨150000

溶剂交换法广泛应用于水泥基材料的干燥和终止水化中。本文综述了溶剂交换对水泥浆体显微结构的影响。阐述了交换参数(样品尺寸、液-固比、交换时间和去除方法)的选取原则。重点论述了常见交换溶剂(异丙醇、丙酮、甲醇和乙醇)与水泥水... 详细信息

溶剂交换法广泛应用于水泥基材料的干燥和终止水化中。本文综述了溶剂交换对水泥浆体显微结构的影响。阐述了交换参数(样品尺寸、液-固比、交换时间和去除方法)的选取原则。重点论述了常见交换溶剂(异丙醇、丙酮、甲醇和乙醇)与水泥水化产物(氢氧化钙、水化硅酸钙和钙矾石)之间存在的物理化学反应。在交换参数和溶剂的影响下,对比分析了水泥基材料的孔结构参数(孔隙率和孔径分布)。最后提出了溶剂交换方法目前存在的问题及研究展望。

关键词：溶剂交换异丙醇丙酮甲醇乙醇微结构

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Improvement of soil fertility and rice yield after long-term application of cow manure combined with inorganic fertilizers

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Journal of Integrative Agriculture 2023年第7期22卷 2221-2232页

作者： GAO Peng zhang Tuo LEI Xing-yu CUI Xin-wei LU Yao-xiong FAN Peng-fei LONG Shi-ping huaNG Jing GAO Ju-sheng zhang Zhen-hua zhang Hui-min College of Resources Hunan Agricultural UniversityChangsha 410128P.R.China Institute of Agro-environment and Ecology Hunan Academy of Agricultural SciencesChangsha 410125P.R.China College of Environmental Science and Engineering China West Normal UniversityNanchong 637002P.R.China Institute of Nuclear Agriculture Science and Space Breeding Hunan Academy of Agricultural SciencesChangsha 410125P.R.China Qiyang Farmland Ecosystem National Observation and Research Station Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesQiyang 426182P.R.China

Fertilization is an effective technique to improve soil fertility and increase crop *** long-term effects of different fertilizers on soil considerably *** 38 consecutive years of different fertilization positioning experiments in a double cropping rice field of Qiyang Red Soil Experimental Station,seven different fertilization treatments including CK(no fertilization),NPK(nitrogen,phosphorus,and potassium fertilizer),M(cow manure),NPKM(nitrogen,phosphorus,and potassium with cow manure),NPM(nitrogen and phosphorus with cow manure),NKM(nitrogen and potassium with cow manure),and PKM(phosphorus and potassium with cow manure)were applied to study the effects on rice yield,soil fertility,and nutrient apparent balance in a paddy *** results showed that the annual average yields of rice in NPKM,NPM,NKM,PKM,M,NPK and CK treatments ranged from 6214 to 11562 kg *** under long-term organic and inorganic treatments(NPKM,NPM,NKM and PKM)were 22.58,15.35,10.53 and 4.41%,respectively,greater than under the NPK *** organic carbon(SOC),total nitrogen(TN),available nitrogen(AN)and available potassium(AK)concentration with long-term organic and inorganic treatment(NPKM,NPM,NKM and PKM)were significantly higher than in inorganic fertilizer(NPK)*** total phosphorus(TP)and available phosphorus(AP)contentration with organic fertilizer combined with inorganic N and P fertilizer treatment(NPKM,NPM and PKM)were significantly higher than with inorganic fertilizer alone(NPK treatments).The average annual rice yield(11562 kg ha-1),SOC(20.88 g kg-1),TN(2.30 g kg-1),TP(0.95 g kg-1),TK(22.50 g kg-1)and AP(38.94 mg kg-1)concentrations were the highest in the NPKM *** soil AN concentration(152.40 mg kg-1)and AK contentration(151.00 mg kg-1)were the highest in the NKM treatment.N and P application led to a surplus of nitrogen and phosphorus in the soil,but NPKM treatment effectively reduced the surplus compared with other *** un

关键词： long-term fertilization rice yield soil fertility nutrient balance

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Simulation research on oxygen mass transfer between steel and slag in IF steel refining process

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Journal of Iron and Steel Research(International) 2020年第4期27卷 409-419页

作者： ai-jun Deng Ding-dong Fan Hai-chuan Wang Can-hua Li School of Metallurgical Engineering Anhui University of TechnologyMa’anshan 243002AnhuiChina Key Laboratory of Metallurgical Emission Reduction&Resource Recycling(Ministry of Education) Ma’anshan 243002AnhuiChina

The effects of oxidizing slag on oxygen mass transfer and inclusions in different stages of IF(interstitial-free)steel refining were investigated by several heat simulation *** results of the experiments showed that the oxidizability of slag changed considerably during different refining *** the content of FeO in the slag within 1 wt.%would narrow the difference of slag oxidizability,stabilize the content of[Al]s in the steel,avoid secondary oxidation of molten steel by the slag,and reduce the *** the mass transfer of FeO in the slag phase was a limiting step,the secondary oxidation reaction occurred at the steel–slag interface;when the diffusion of oxygen in the molten steel was a limiting step,the secondary oxidation reaction took place inside the molten *** oxygen transfer rate was affected by the mass transfer coefficient of *** every 0.0001m/s increase in mass transfer coefficient,the oxygen transfer rate increased by about 2.2×10^-6 min^-*** changing the mass transfer coefficient,the oxygen transfer rate of the slag to the molten steel can be controlled.

关键词： IF steel Slag Steel–slag interface Inclusion Oxygen mass transfer Mass transfer coefficient

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Ribosome biogenesis in disease:new players and therapeutic targets

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Signal Transduction and Targeted Therapy 2023年第2期8卷 484-505页

作者： Lijuan Jiao Yuzhe Liu Xi-Yong Yu Xiangbin Pan Yu zhang Junchu Tu Yao-hua Song Yangxin Li Institute for Cardiovascular Science and Department of Cardiovascular Surgery First Affiliated Hospital and Medical College of Soochow UniversityCollaborative Innovation Center of HematologySoochow UniversitySuzhouJiangsu215123P.R.China Department of Orthopedics the Second Hospital of Jilin UniversityChangchunJilin130000P.R.China Key Laboratory of Molecular Target&Clinical Pharmacology and the NMPA State Key Laboratory of Respiratory Disease Guangzhou Medical UniversityGuangzhouGuangdong511436P.R.China Department of Structural Heart Disease National Center for Cardiovascular DiseaseChina&Fuwai HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijingP.R.China Key Laboratory of Cardiovascular Appratus Innovation Beijing100037P.R.China Cyrus Tang Hematology Center Collaborative Innovation Center of HematologySoochow UniversityNational Clinical Research Center for Hematologic Diseasesthe First Affiliated Hospital of Soochow UniversitySuzhouP.R.China State Key Laboratory of Radiation Medicine and Protection Soochow UniversitySuzhou215123P.R.China

The ribosome is a multi-unit complex that translates mRNA into *** biogenesis is the process that generates ribosomes and plays an essential role in cell proliferation,differentiation,apoptosis,development,and *** mTORC1,Myc,and noncoding RNA signaling pathways are the primary mediators that work jointly with RNA polymerases and ribosome proteins to control ribosome biogenesis and protein *** of mTORC1 is required for normal fetal growth and development and tissue regeneration after *** is implicated in cancer development by enhancing RNA Pol II activity,leading to uncontrolled cancer cell *** deregulation of noncoding RNAs such as microRNAs,long noncoding RNAs,and circular RNAs is involved in developing blood,neurodegenerative diseases,and *** review the similarities and differences between eukaryotic and bacterial ribosomes and the molecular mechanism of ribosome-targeting antibiotics and bacterial *** also review the most recent findings of ribosome dysfunction in COVID-19 and other conditions and discuss the consequences of ribosome frameshifting,ribosome-stalling,and *** summarize the role of ribosome biogenesis in the development of various ***,we review the current clinical trials,prospective vaccines for COVID-19,and therapies targeting ribosome biogenesis in cancer,cardiovascular disease,aging,and neurodegenerative disease.

关键词： mTORC1 consequences jointly

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