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Distance-basedα-amylase biosensor fabricated with amylopectin-coated mesoporous membrane

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Chinese Chemical Letters 2024年第1期35卷 446-450页

作者： Binglu Zhao Mashooq Khan yulin liu Wenjun Tai Chongyang Mu Wenli Wu Mei Zhao Yaohong Ma Li Yu Jin-Ming Lin Qiongzheng Hu Qilu University of Technology(Shandong Academy of Sciences) Shandong Analysis and Test CenterJi’nan 250014China School of Pharmaceutical Sciences Qilu University of Technology(Shandong Academy of Sciences)Ji’nan 250014China Key Laboratory of Colloid and Interface Chemistry Shandong UniversityMinistry of EducationJi’nan 250100China Key Laboratory for Biosensors of Shandong Province Biology InstituteQilu University of Technology(Shandong Academy of Sciences)Ji’nan 250353China Beijing Key Laboratory of Microanalytical Methods and Instrumentation MOE Key Laboratory of Bioorganic Phosphorus Chemistry&Chemical BiologyDepartment of ChemistryTsinghua UniversityBeijing 100084China

Paper-based biosensors are widely employed in point-of-care testing(POCT)due to their convenience,portability,low cost,and ease of use.This study reports an integrated distance-based paper biosensor fabricated with a mesoporous membrane coated with stimuli-responsive polymer.The detection ofα-amylase(AMY)using amylopectin-coated mesoporous membrane is demonstrated as an example.After introducing the AMY solution,it is observed that the aqueous solution flows along the paper strip due to AMY-catalyzed hydrolysis of amylopectin.The flow distance is proportional to the concentration of AMY with a detection limit as low as 4 mU/mL.In addition,the detection of AMY is demonstrated in human serum.Furthermore,the inhibitory effect of acarbose on AMY is evaluated.This reagent-free and disposable biosensor allows single-step rapid detection of the analyte.This approach is very promising for the development of user-friendly,equipment-free,and cost-effective biosensors with remarkable sensitivity and excellent selectivity for disease diagnosis and hypoglycemic drug screening.

关键词： Paper biosensor α-Amylase Stimuli-responsive polymer Mesoporous membrane Distance Point-of-care testing

Migration routes of the endangered Oriental Stork(Ciconia boyciana)from Xingkai Lake,China,and their repeatability as revealed by GPS tracking

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Avian Research 2023年第2期14卷 215-222页

作者： Zeyu Yang Lixia Chen Ru Jia Hongying Xu Yihua Wang Xuelei Wei Dongping liu Huajin liu yulin liu Peiyu Yang Guogang Zhang Key Laboratory of Forest Protection of National Forestry and Grassland Administration National Bird Banding Center of ChinaEcology and Nature Conservation InstituteChinese Academy of ForestryBeijing100091China Xingkai Lake National Nature Reserve of Heilongjiang JixiHeilongjiang158300China

The Oriental Stork(Ciconia boyciana)is listed as'Endangered'on the International Union for the Conservation of Nature(IUCN)Red List of Threatened Species and is classified as a first category nationally protected bird species in China.Understanding this species'seasonal movements and migration will facilitate effective conservation to promote its population.We tagged 27 Oriental Stork nestlings at Xingkai Lake on the Sanjiang Plain in Heilongjiang Province,China,used GPS tracking to follow them over the periods of 2014-2017 and 2019-2022,and confirmed their detailed migratory routes using the spatial analysis function of ArcGIS 10.7.We discovered four migration routes during autumn migration:one common long-distance migration route in which the storks migrated along the coastline of Bohai Bay to the middle and lower reaches of the Yangtze River for wintering,one short-distance migration route in which the storks wintered in Bohai Bay and two other migration routes in which the storks crossed the Bohai Strait around the Yellow River and wintered in South Korea.There were no significant differences in the number of migration days,residence days,migration distances,number of stopovers and average number of days spent at stopover sites between the autumn and spring migrations(P>0.05).However,the storks migrated significantly faster in spring than in autumn(P=0.03).The same individuals did not exhibit a high degree of repetition in their migration timing and route selection in either autumn or spring migration.Even storks from the same nest exhibited considerable between-individual variation in their migration routes.Some important stopover sites were identified,especially in the Bohai Rim Region and on the Songnen Plain,and we further explored the current conservation status at these two important sites.Overall,our results contribute to the understanding of the annual migration,dispersal and protection status of the endangered Oriental Stork and provide a scientific basis for conservation decisions and the developmen

关键词： Autumn migration GPS tracking Oriental stork Repeatability Spring migration Stopover site

增值税进项留抵下的增值税税率与企业资产配置优化

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系统工程理论与实践 2024年第3期44卷 1034-1052页

作者：李嘉明李毅博刘渝琳重庆大学经济与工商管理学院重庆400030 重庆大学公共管理学院重庆400030 重庆大学公共经济与公共政策研究中心重庆400030

文章选取增值税进项留抵视角,考虑企业在增值税税率下调政策带来的税负效应和税收红利共享(或税负转嫁)效应下如何优化资产配置.税收红利共享(或税负转嫁)可影响以下价格组合:(i)不含(增值)税销售价格、购买价格;(ii)不含(增值)税销售... 详细信息

文章选取增值税进项留抵视角,考虑企业在增值税税率下调政策带来的税负效应和税收红利共享(或税负转嫁)效应下如何优化资产配置.税收红利共享(或税负转嫁)可影响以下价格组合:(i)不含(增值)税销售价格、购买价格;(ii)不含(增值)税销售价格、含(增值)税购买价格;(iii)含(增值)税销售价格、不含(增值)税购买价格;(iv)含(增值)税销售价格、购买价格.研究发现:1)销项税率下调:规模报酬递减下,企业会增多投资资本与劳动力,减少投资金融资产,否则相反;2)进项税率下调:情形(i)下,规模报酬递增且金融资产预期回报率低于附加税税率或规模报酬递减且金融资产预期回报率高于附加税税率下,企业会增多投资资本与劳动力,否则相反;情形(ii)∼(iv)下,规模报酬递减时,企业会减少投资资本与劳动力,增多投资金融资产,否则相反;3)增值税销、进项税率同时下调:情形(i)、(iii)下,规模报酬递增且金融资产预期回报率高于附加税税率时,企业会减少投资资本与劳动力,增多投资金融资产;规模报酬递减且金融资产预期回报率高于附加税税率时,企业会增多投资资本与劳动力.文章使用制造业等相关数据,模拟四种价格组合增值税税率与资产配置优化的关系以回证结论;文章也使用我国2016–2021年A股上市公司数据,发现实证结果也回证了结论.而在我国规模报酬递减的现行国情下,文章也从企业微观行为说明下调增值税税率的原因.

关键词：增值税进项留抵增值税税率下调税收红利共享(或税负转嫁) 销售、购买价格资产配置优化

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动态专利技术网络视域下技术集群识别

情报杂志 2024年第4期43卷 114-120页

作者：刘玉林菅利荣南京航空航天大学经济与管理学院南京211106 安徽商贸职业技术学院电子商务学院芜湖241002

[研究目的]国与国之间的技术资源竞争已经从单一技术竞争转向技术集群竞争。从动态专利技术网络的角度识别技术集群,有助于企业和研发人员了解技术结构、挖掘技术机会和预测技术未来,从而在技术研发和竞争中获得优势。[研究方法]采用自... 详细信息

[研究目的]国与国之间的技术资源竞争已经从单一技术竞争转向技术集群竞争。从动态专利技术网络的角度识别技术集群,有助于企业和研发人员了解技术结构、挖掘技术机会和预测技术未来,从而在技术研发和竞争中获得优势。[研究方法]采用自注意力机制学习出专利文档特定词向量,融合属性和功能技术因子等先验信息生成专利技术向量,计算专利技术相似度后构建动态专利技术网络,采用带节点增量的Louvain算法识别技术集群。[研究结论]在以美国电商数据技术为例的实证研究中发现了数据系统、数据设备、数据安全等12个技术集群及1个技术集群融合事件,实证分析进一步验证了该方法的有效性。

关键词：专利技术技术集群技术集群识别动态专利技术网络技术相似度 Louvain算法

新质生产力促进就业结构转型了吗——基于超边际一般均衡视角的研究

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经济评论 2024年第3期 57-74页

作者：王成刘渝琳重庆大学公共管理学院 400044 重庆大学公共经济与公共政策研究中心 400044

本文基于新兴古典经济学理论框架,以新质生产力高质量、高科技、高效能的核心表征为出发点,构建了传统生产力、传统-新质生产力、新质生产力演进的非对称内生分工演进模型。研究发现:内生分工演化下传统-新质生产力融合发展与新质生产... 详细信息

本文基于新兴古典经济学理论框架,以新质生产力高质量、高科技、高效能的核心表征为出发点,构建了传统生产力、传统-新质生产力、新质生产力演进的非对称内生分工演进模型。研究发现:内生分工演化下传统-新质生产力融合发展与新质生产力跃升发展将促进人均真实收入及社会整体福利水平大幅提升,为就业结构转型提供经济支持。进一步研究发现:伴随新质生产力的市场均衡结构演进,中高端就业规模呈跳跃式增长且随交易效率提升而促进就业结构转型升级,推动中低端就业人员向中高端就业演化。此外,降低新质生产力固定学习成本、提高市场交易效率将有力助推市场均衡结构的演进,摆脱以传统生产力为主导的就业结构失衡,削减低端就业人员占比。本文为加快发展新质生产力、促进就业结构转型提供了政策启示。

关键词：新质生产力分工演进交易效率就业结构转型超边际分析

Soil microbial respiration is regulated by stoichiometric imbalances: Evidence from a humidity gradient case

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Pedosphere 2023年第6期33卷 905-915页

作者： Jiwei LI Jiangbo XIE Jianzhao WU Yongxing CUI Lingbo DONG yulin liu Xuying HAI Yan LI Zhouping SHANGGUAN Kaibo WANG Changhui PENG Lei DENG State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau College of Soil and Water Conservation Science and Engineering(Institute of Soil and Water Conservation)Northwest A&F UniversityYangling 712100China Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityLin'an 311300China Sino-French Institute for Earth System Science College of Urban and Environmental SciencesPeking UniversityBeijing 100871China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China Center of CEF/ESCER Department of Biological ScienceUniversity of Quebec at MontrealMontreal H3C 3P8Canada

Humidity not only affects soil microbial respiration(SMR) directly, but, indirectly by regulating the availability of soil water and nutrients. However,the patterns of direct and indirect effects of humidity on SMR over large precipitation gradients remain unclear, limiting our understanding of the effects of precipitation changes on soil C cycle. Here, we investigated the relationships among humidity, soil nutrients, and SMR by identifying stoichiometric imbalances, microbial elemental homeostasis, and microbial C use efficiency along a precipitation gradient at a continental scale. The relationship between SMR and humidity index(HI) corresponded to a Richard’s curve with an inflection point threshold value of approximately 0.7. Soil microbial respiration increased with increasing humidity in drier areas(HI 0.7). Soil microbial communities regulated their enzyme production to maintain a strong stoichiometric homeostasis in drier areas;enzyme production, microbial biomass, and threshold elemental ratios were non-homeostatic under P limitation in wetter areas, which further contributed to the increase in SMR. Our results identified a moisture constraint on SMR in drier areas and highlighted the importance of nutrient(especially for P) limitations induced by humidity in regulating SMR in wetter areas. Understanding the modulation of SMR via soil enzyme activity may improve the prediction of soil C budget under future global climate change.

关键词： carbon use efficiency ecological stoichiometry microorganisms nutrient limitations precipitation soil enzyme activities stoichiometric homeostasis

De novo assembly of the seed transcriptome and search for potential EST-SSR markers for an endangered, economically important tree species: Elaeagnus mollis Diels

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Journal of Forestry Research 2020年第3期31卷 759-767页

作者： yulin liu Siqiao Li Yunying Wang Pingyu liu Wenjing Han College of Forestry Northwest A&F UniversityYangling 712100People’s Republic of China

Seeds of Elaeagnus mollis(Elaeagnaceae) produce an edible oil and contain more vitamin E(Ve) than major oil-seed crops. Despite its economic value, there is no information on its genome sequence. Here, we used the Illumina platform to determine the seed transcriptome of E.mollis to identify the genes related to Ve biosynthesis and potential simple sequence repeat(SSR) markers. In total, 100,999 unigenes were obtained with an average length of 605 bp and N50 of 985 bp. Of these unigenes,52,256(51.7%) were annotated in at least one public database(NT, NR, PFAM, Swiss Prot, KOG, KO, and GO)in searches using blastn/x. The unigene annotation identified 15 unigenes encoding six enzymes(GGR, HPPD,HPT/VTE2, MPBQ-MT/VTE3, TC/VTE1, and c-TMT/VTE4) putatively involved in Ve biosynthesis. In addition,16,810 SSRs distributed in 14,057 unigenes were mined.Of these, 2820, 583, and 3423 SSRs were located in the 50–UTR, coding sequence(CDS), and 30–UTR regions,respectively, while the remaining 9984 SSRs had undetermined physical locations. The largest group of repeat motifs comprised mononucleotide repeats(70.76%), followed by dinucleotide(15.59%) and trinucleotide(12.10%)repeats. AG/CT(8.69%) and AAG/CTT(4.15%) were the main dinucleotide and trinucleotide repeats, respectively.Furthermore, 9597 SSR-specific primer pairs were designed. Among 100 primer pairs selected randomly to determine their usefulness, 53 proved to be efficient. To the our best of knowledge, this work is the first study of the E. mollis transcriptome and constitutes valuable genomics data for future genetic engineering studies to alter the amount of Ve. The identified potential EST-SSR markers can be used for population genetics studies and assistedbreeding of E. mollis.

关键词： Elaeagnaceae Elaeagnus mollis Transcriptome Vitamin E Simple sequence repeats(SSR)

Effect of Fe, Si and Cooling Rate on the Formation of Fe-and Mn-rich Intermetallics in Al–5Mg–0.8Mn Alloy

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Journal of Materials Science & Technology 2016年第4期32卷 305-312页

作者： yulin liu Lei Luo Chaofei Han Liangyun Ou Jijie Wang Chunzhong liu Liaoning Provincial Key Laboratory of Light Alloys and Processing Technology School of Materials Science and Engineering Shenyang Aerospace University

The Fe- and Mn-rich intermetallics are of great effect on the mechanical properties of the AA5083 type alloy （Al-5Mg-0.8Mn）. The effect of Fe, Si and cooling rate on the formation of the intermetallics were investigated by analyzing the microstructures of the alloys with different Fe and Si contents. The results indicated that increasing the Fe content resulted in the increase of the Al6（Fe,Mn） phase in both amount and size. In the alloys with high Fe content, the platelet-like Al6（Fe,Mn） compounds lined up and formed a band. Increasing the content of Si resulted in the increase of the Mg2Si phase which formed a network structure. Increasing the cooling rate significantly refined the intermetallics. However, increasing the cooling rate did not change the characteristic of the intermetallic compounds in the alloys with low or medium Si contents. For the alloys with high contents of Fe and Si under the condition of near-rapid cooling, the Fe- and Mn-rich intermetallic compound changed to the quaternary Al15（Fe,Mn）3Si phase and displayed a fine fish bone or Chinese script structure. The refinement of the intermetallics would allow higher tol- erance of Fe and Si contents in the AA5083 alloy produced, for instance, via the continuous strip casting process.

关键词： Aluminum alloyIntermetallicsPhase transformationCastingRapid solidification

Influence of olivine grains on K-Ar dating of Late-Cenozoic olivine basalts in eastern China

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Chinese Science Bulletin 1998年第19期43卷 1663-1665页

作者： Zhiguo Mu yulin liu Baoling Huang Peking Univ Dept Geol Beijing 100871 Peoples R China

Five Late-Cenozoic olivine basalt samples, taken from 3 young volcanoes (Keluo, Lianhuashan and Qinglongshan) located in the north of Heilongjian Province, were dated by the conventional K-Ar dating method. The apparent ages of whole rock are (0.06±0.01) Ma,( 0.15±0.03) Ma, (0.17±0.02) Ma, (21.10±0.13) Ma and (24.46±0.10) Ma, respectively. In the crushed sample grains (mush number 80-100)olivine(including phynocryst and xenocryst)was picked out under a binocular microscope, then apparent ages obtained are (0.03±0.01) Ma, (0.06±0.01) Ma, (0.07±0.03) Ma, (2.31±0.02) Ma and (1.50±0.21) Ma, respectively. The apparent ages of the olivine-picked out sample are come down (younger)50 to over 90. There are a lot of the Late-Cenozoic volcanic olivine basalt outcropping in eastern China, probably the age-datings of those basalt samples in which olivine grains are unpicked out are older than the true geological ages. The inference and conclusion drawn from those datings should be renewed.

关键词： olivine crystalline grain Late-Cenozoic olivine basalt K-Ar dating eastern China.