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On the Four Academic Orientations of Academic Orientations:A Concurrent Discussion of Jullien and Cao Shunqing's Criticism on Value of Qian Zhongshu's Common Core Literature Studies
No full text林玮生，广东外语外贸大学外国文学文化研究中心/中国语言文化学院教授、博士生导师。【中文摘要】百年来，比较文学纷争的一个重要原因是比较学者“研究向度”的分异。“研究向度”是指个体比较学者潜在、不自觉、难以被自己所觉察的研究偏向。基于“平行”与“影响”两大类型以及“趋同”与“趋异”两大方向，“研究向度”可四分为:平行/趋同、平行/趋异、影响/趋同与影响/ 趋异。比较学者一般在这四向中偏向其一，不同“研究向度”具有等价性。但长期以来，由于比较学者“研究向度”意识的缺失，时常导致对“异向”者的误读与指责,如于连、曹顺庆（“平行/趋异”） 对钱钟书“共同诗心”(“平行/趋同”）研究价值的批评与否定。“研究向度”的系统揭示，可使比较学者重审本己与他者“研究向度”的差异，实现对本己的超越和对他者的接纳。
【Abstract】Over the past century，one of the important reasons for the disputes in the field of comparative literature is the lack of attention to academic orientations. Academic orientation refers to a comparatist’ research direction，which is difficult to be perceived by himself or herself. This paper proposes that based on the types of “parallel” and “influence” and the directions of “convergence” and “divergence”，comparatists’ academic orientations fall into four categories:parallel/convergence，parallel divergence，influence/ convergence and influence/divergence. Generally speaking，each comparatist tends to choose one of them，and each orientation enjoys the same equivalence. However，for a long time，because of the limited understanding of academic orientations， there are misunderstanding and accusations among comparatists. Jullien's and Cao Shunqing's criticism on the value of Qian Zhongshu's common core literature studies is a typical example. The revelation of the academic orientation system will enable comparatists to re-examine themselves and others in academic orientations and realize the transcendence of themselves and the acceptance of others. The strategic synergy between China and Indonesia provides new ideas for the development of “Belt and Road” and the formation of a new pattern of all-round opening up.国家社会科学基金后期资助项目“比较文学个体性向度研究”（18FWW015)；广东省哲学社会科学 “十三五”规划2018年度一般项目“比较文学个体性向度研究”（GD18CWW05);广东外语外贸大学外国文学文化研究中心2018年度标志性成果培植课题“中国与希腊悲剧形态比较研究”（18BZCG06
多种环境条件下的亲本效应均惠及后代：基于动植物数据的元分析研究
No full text在生物界，当上代生存环境恶劣时，是否一定会带给后代一个消极、负面的影响?环境与生态学院李庆顺教授课题组就此展开了大数据元分析研究，综合分析了从上世纪90年代至今的大量相关研究数据,从关键词索引得到的1000余篇论文中，筛选出139篇研究论文，这些论文涉及112个物种，包括不同的亲代环境处理、不同的子世代等。结果发现，对那些世代周期短、活动能力受限的一年生植物和无脊椎动物（如昆虫），无论上一代经历的是优质环境还是恶劣环境，这些经历总能使子代受益。但是，对于脊椎动物如老鼠和人等，只有上代经历优质环境才能使其子代受益。这一“源头”上的机制发现或为今后快速改良农作物，使其更有效应对干旱、升温、虫害等不良影响提供一种思路和方向。The adaptive value of transgenerational effects (the ancestor environmental effects on offspring) in changing environments has received much attention in recent years, but the related empirical evidence remains equivocal. Here, we conducted a meta‐analysis summarising 139 experimental studies in plants and animals with 1170 effect sizes to investigate the generality of transgenerational effects across taxa, traits, and environmental contexts. It was found that transgenerational effects generally enhanced offspring performance in response to both stressful and benign conditions. The strongest effects are in annual plants and invertebrates, whereas vertebrates appear to benefit mostly under benign conditions, and perennial plants show hardly any transgenerational responses at all. These differences among taxonomic/life‐history groups possibly reflect that vertebrates can avoid stressful conditions through their mobility, and longer‐lived plants have alternative strategies. In addition to environmental contexts and taxonomic/life‐history groups, transgenerational effects also varied among traits and developmental stages of ancestors and offspring, but the effects were similarly strong across three generations of offspring. By way of a more comprehensive data set and a different effect size, our results differ from those of a recent meta‐analysis, suggesting that transgenerational effects are widespread, strong and persistent and can substantially impact the responses of plants and animals to changing environments.This study is supported by the National Natural Science Foundation of China (grant No. 31600291 to Y‐YZ) and the Fundamental Research Funds for the Central Universities in China (grant No. 20720170074 to Y‐YZ)
Photocatalytic regio- and stereoselective C(sp3)–H functionalization of benzylic and allylic hydrocarbons as well as unactivated alkanes
Get PDFC(sp3)–H键的直接官能团化具有原子、步骤经济、原料来源丰富等特点，备受合成化学家的青睐。然而，这些化学键的高键能、低极性等特征使其反应性差；相近能量化学键的存在也使反应的选择性难以控制。因此，C(sp3)–H键的直接、选择性转化一直是有机合成中的难题。课题组基于近期在手性廉价金属配合物催化自由基可控不对称合成方面的工作基础（Nat.Commun.2019,10,3804、J. Am.Chem.Soc.2018,140,15850、Chem.Sci.2018,9,4562），提出了手性铜、镍、钴配合物与商业化醌类可见光氢转移催化剂共催化的策略，在极为温和的光反应条件下，实现了石油、天然气中原材料向高附加值手性化合物的区域、立体选择性转化，为烃类资源的优化利用及药物分子的后期改造提供了有效手段，也为纯烃分子作为反应试剂直接使用提供了新思路。该方法适用于苄基、烯丙基类化合物、环烷烃、链烷烃等40余种烃类分子，也适用于一些药物及生物活性分子（如celebrex、skelaxin等）的后期官能化中。此外，廉价金属/氢转移光催化剂体系也展现了通过改变催化剂金属中心获得手性反转产物的独特现象，为立体发散性合成提供了极为简便的策略。
本工作由龚磊副教授指导，实验部分由2016级博士生李延军和已毕业硕士生雷梦合作完成.The selective functionalization of inert C(sp3)–H bonds is extremely attractive in organic synthesis and catalysis science, but the conversion of hydrocarbons lacking directing groups into chiral molecules through catalytic C(sp3)–H functionalization is formidably challenging. Here, to address this problem, we have developed a photochemical system consisting of a hydrogen atom transfer organophotocatalyst and a chiral catalyst containing an earth-abundant metal. With the cooperative catalysts and imine partners, a wide range of benzylic, allylic hydrocarbons and unactivated alkanes can be converted to functionalized chiral products. The readily tunable bisoxazoline catalysts of copper or other metals exhibit precise regional recognition and asymmetric induction towards these inert C–H bonds. The reactions are applicable to many compounds including small hydrocarbons, branched alkanes, cycloalkanes and more complex medicinal agents. This method provides an economic and rapid construction of optically active compounds, starting from the most basic chemical feedstocks.We gratefully acknowledge funding from the National Natural Science Foundation of China (grant no. 21572184), the Natural Science Foundation of Fujian Province of China (grant no. 2017J06006) and the Fundamental Research Funds for the Central Universities (grant no. 20720190048).
研究工作得到国家自然科学基金（21572184）、福建省杰出青年基金（2017J06006）、南强青年拔尖人才计划（B类）、厦门大学校长基金（20720190048）等项目支持
scDAPA: detection and visualization of dynamic alternative polyadenylation from single cell RNA-seq data
Get PDFMotivation: Alternative polyadenylation (APA) plays a key post-transcriptional regulatory role in mRNA stability and functions in eukaryotes. Single cell RNA-seq (scRNA-seq) is a powerful tool to discover cellular heterogeneity at gene expression level. Given 30 enriched strategy in library construction, the most commonly used scRNA-seq protocol—10 Genomics enables us to improve the study resolution of APA to the single cell level. However, currently there is no computational tool available for investigating APA profiles from scRNA-seq data.
Results: Here, we present a package scDAPA for detecting and visualizing dynamic APA from scRNA-seq data.
Taking bam/sam files and cell cluster labels as inputs, scDAPA detects APA dynamics using a histogram-based
method and the Wilcoxon rank-sum test, and visualizes candidate genes with dynamic APA. Benchmarking results
demonstrated that scDAPA can effectively identify genes with dynamic APA among different cell groups from
scRNA-seq data.This research was supported in part by the Fundamental Research Funds for the Central Universities in China [Xiamen University: 20720170076 and 20720190106], and the National Natural Science Foundation of China [61802323, 31801268 and 61573296]
Criticism of Marxist Political Economy on Capitalist Ideology
No full text胡芳，四川大学马克思主义学院特聘研究员，贵州大学博士生导师，法学博士。【中文摘要】在《1857—1858年经济学手稿》中，马克思不再停留在资本主义观念层面对绝对精神的“外在”批判，转而深入“市民社会”对“那些统治个人的物质关系的理论表现”进行“内在”批判。马克思从资本主义的生产、生活出发,有机地将劳动与工资、货币、资本之间的关系统一起来，一步一步地将隐藏在其背后的物化生产关系、社会关系、价值颠倒的虚幻面纱揭开。他深刻地揭露了所谓“等价交换”的工资实质上的不平等不自由、货币对工人统治的权力不平等、资本对人的价值的颠倒，向世人展示了资本主义“赤裸裸”的面貌，戳穿了资产阶级“公道、正义、民主、平等、和谐” 等虚伪的空话，否定资本主义剥削制度,从而促成资产阶级意识形态的合法化危机。
【Abstract】Marx no longer stays in the capitalist concept of the “external”criticism of the absolute spirit，but goes deep into the “citizen society” to criticize “the theoretical expression of the material relations that govern the individual” in 1857—1858 Economic Manuscript. Starting from the production and life of capitalism，Marx organically put the system of labor and wages，money，and capital together，and gradually unveiled the false veil of materialized production relations，social relations，and reversal of value hidden behind it,which exposed profoundly the inequality and inequality of wages under the apparent “equivalence exchange”，the inequality of power of money over workers，and the falsity of capitals reversal of human value，and showed the world the “naked” face of capitalism. It debunked the false empty words of the bourgeoisie， such as “justice，justice，democracy，equality，and harmony”，negated the capitalist exploitation system，and formed a legitimate crisis of bourgeois ideology.中央高校基本科研业务费专项资金资助项目“马克思恩格斯资本主义意识形态批判理论及其当代价值研究”（SQ2019-MY05
A Low Noise Temperature Control System for Nanopore-Based Single Molecule Analysis
No full text纳米孔道检测技术是一种利用单个分子测量界面实现在单分子水平上测量DNA、RNA、蛋白、多肽等生物分子的高灵敏的单分子检测技术. 由于单个分子与纳米孔道的相互作用受热力学控制，亟需精准控制纳米孔道单分子分析的实验温度. 因此，本文研制了一种低噪音控温系统用于具有皮安级电流分辨的纳米孔道单分子实验，以实现精确调控测量时的环境温度. 该系统利用半导体制冷片的热电效应对检测池环境加热/制冷，通过对高精度热敏电阻进行电磁屏蔽以实现在温度反馈的同时避免噪音的引入. 利用比例-积分-微分算法进行控制，达到高精度快速控温的要求. 该系统控温精度为±1 °C，无额外噪音引入至超灵敏纳米孔道单分子测量，获得了25 °C到5 °C下Poly(dA)5与单个气单胞菌溶素（Aerolysin）分子界面间作用产生信号的差异，应用于研究单分子与纳米孔道相互作用的热力学行为.Nanopore employs a single bio-molecule interface, which is a highly sensitive single-molecule detection technology for measuring single biomolecules such as DNA, RNA, protein, and peptide. The interaction between single molecule and nanopore is thermodynamically controlled. Therefore, it is urgent to precisely control the temperature of the nanopore system without introduction of any noise. In this paper, we have developed a low-noise temperature control system for single-molecule detection of nanopores to achieve precise regulation at the ambient temperature during measurements. The system utilizes the thermoelectric effect of the semiconductor refrigerating chip to heat or cool the detection chamber, while adopts electromagnetically shielded high-precision thermistor to achieve the temperature feedback which avoids the introduction of noise at the same time. The proportional-integral-differential algorithm is used to provide the high-precision and rapid temperature control. The system was further applied in measuring the interaction between Poly(dA)5 and aerolysin nanopore at 25 oC to 5 oC. This system could be used to characterize the thermodynamic and kinetic information of the single molecules.国家自然科学基金项目( Nos. 21834001，61871183)、上海市教育委员会科研创新计划(No. 2017-01-07-00-02-E00023)、上海市启明星计划（No. 19QA1402300）、上海市教育委员会和上海教育发展基金会支持的“晨光”项目（No. 17CG27）资助 作者联系地址：1. 华东理工大学化学与分子工程学院，上海 200237；2. 南京大学化学化工学院，生命分析化学国家重点实验室，江苏 南京 210023Author's Address: 1. School of Chemistry & Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China; 2. State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, Jiangsu, China通讯作者E-mail：[email protected]
Investigations in Electrochemical Thermodynamic and Kinetic Properties of As-Cast and As-Quenched CeMg10Ni2 Hydrogen Storage Alloys
No full text为了改善CeMg10Ni2合金的电化学储氢性能，快淬技术被用来制备具有非晶纳米晶结构的CeMg10Ni2合金. 运用X射线衍射及高分辨透射电镜对合金的微观结构及其相组成进行分析. 通过恒电流充放电、高倍率放电、交流阻抗以及动电位极化测试对合金的电化学性能进行了详细研究. 研究结果表明，铸态合金由多相结构组成，经过快速凝固处理的合金内部含有大量的非晶纳米晶结构，而且增加的凝固速度可以增强合金内部的非晶纳米晶形成能力. 快速凝固处理减小了合金的热力学参数（ΔH和ΔS），降低了合金氢化物的热稳定性，改善了电化学放电容量. 另外，快速凝固处理显著改善了合金的电化学动力学性能，合金的表观活化能变化进一步解释了这一结论.In order to improve the electrochemical hydrogen storage properties of CeMg10Ni2 alloy, the rapid quenching technology was used to prepare CeMg10Ni2 alloys with nano-crystalline and amorphous structure. The microstructures of as-cast and as-spinning sample were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The electrochemical hydrogen storage properties were investigated by an automatic galvanostatic charging/discharging, high rate discharging (HRD), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques. The results revealed that the as-cast alloy was composed of multiphase structures. The as-quenched alloys were made up of nano-crystalline and/or amorphous structures, and the rapid solidification technology enhanced the glass forming ability of alloys. The rapid spinning technology brought on a reduction in thermodynamic parameters (ΔH and ΔS), which lowered the stability of hydride and ameliorated the discharging capacity of alloy sample. Besides, the as-quenched alloys held better electrochemical kinetics, which may be interpreted by the variation of activation energy.国家自然科学基金（No. 51761032和51871125）、内蒙古自然科学基金（No.2017BS0507和No. 2018LH05010）、内蒙古科技成果转化项目（No.CGZH2018152）及内蒙古科技大学创新基金项目（No.2014QDL015）作者联系地址：1. 钢铁研究总院功能材料研究所，北京市海淀区，100081; 2. 内蒙古科技大学材料与冶金学院，内蒙古自治区包头市，014010Author's Address: 1. Department of Functional Material Research, Central Iron and Steel Research Institute,Beijing 100081, China; 2. The School of Materials and Metallurgy, Inner Mongolia University of Science and Technology, Baotou 014010, Inner Mongolia, China通讯作者E-mail：[email protected]
Electrochemical Preparation and Photocatalytic Performance of LaNiO3/TiO2 Nanotube Arrays
No full text利用脉冲电沉积与高温退火相结合的方法制备了镍酸镧(LaNiO3)纳米颗粒负载的二氧化钛(TiO2)纳米管阵列. 修饰于TiO2纳米管阵列上的LaNiO3纳米颗粒粒径小（< 10 nm）、分布均匀、负载量可控，一些LaNiO3纳米颗粒沉积于TiO2纳米管内. 紫外可见吸收光谱显示，LaNiO3/TiO2纳米管阵列的吸收带边较TiO2纳米管阵列明显红移，可见光吸收明显增强. 可见光下光催化降解罗丹明B（RhB）的结果表明，脉冲循环沉积500次制得的LaNiO3/TiO2纳米管阵列的光催化活性最佳，其对RhB光催化降解速率是TiO2纳米管阵列的3.5倍，并且表现出极好的光催化稳定性.The LaNiO3/TiO2 nanotube arrays were prepared by pulse electrodeposition combined with high temperature annealing. The LaNiO3 nanoparticles modified on the TiO2 nanotube arrays had small particle size (< 10 nm), uniform distribution and controllable loading. Some LaNiO3 nanoparticles were deposited inside the TiO2 nanotubes. The UV-visible absorption spectra displayed that the absorption band edge of LaNiO3/TiO2 nanotube arrays was obviously red-shifted as compared with that of TiO2 nanotube arrays, and the visible light absorption was enhanced significantly. The photocatalytic degradation results of rhodamine B (RhB) under visible light showed that the LaNiO3/TiO2 nanotube arrays prepared by pulse electrodeposition for 500 cycles had the optimum photocatalytic activity, and the photocatalytic degradation rate of RhB was 3.5 times that of TiO2 nanotube arrays. Furthermore, the LaNiO3/TiO2 nanotube arrays presented the excellent photocatalytic stability.国家自然科学基金(No. 21621091)和广东省自然科学基金（No. 2016A030313845）资助作者联系地址：1. 厦门大学 化学化工学院，福建 厦门 361005；2. 厦门大学深圳研究院，深圳518000；3. 宁德市师范学院，特色生物化工材料福建省重点实验室，福建 宁德 352100Author's Address: 1. State Key Laboratory for Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian Province, China; 2. Shenzhen Research Institute of Xiamen University, Shenzhen 518000, China; 3. Fujian Provincial Key Laboratory of Featured Materials in Biochemical Industry, Ningde Normal University, Ningde 352100, Fujian Province, China通讯作者E-mail：[email protected]
Tax Rigidity：The Characteristics of Corporate Tax Burden Under the Central-Planned Tax Administration in China
No full text【中文摘要】长期以来，我国实行“以计划任务为中心”的税收征管模式。这种征管模式对微观层面企业税负产生了何种影响？本文利用 2003～2016 年我国A股主板上市公司数据，对此问题进行了考察。我们发现，我国微观企业税负存在刚性特征：企业收入下降时，税费支出随之降低的速度，显著低于企业收入上升时税费支出增加的速度。这种刚性特征在企业主体税种增值税、所得税中均有体现。进一步研究发现，企业税负刚性主要表现在当年预算收入计划完成或者超额完成的省（区、市）。并且，在税收征管强度较高的地区，企业税负刚性显著更高。此外，我们还发现，企业税负刚性主要存在于税负较重的企业。本文揭示了我国企业税负的刚性特征，有助于理解我国企业税负现实，对当前制定“减税降费”落实政策也具有参考价值。
【Abstract】For decades，China has adopted taxation administration based on the top-down central-planned system that usually specify a minimum amount of taxes to be collected. This means that once the tax-collecting plans are formulated，they will be at least fulfilled in general.In this paper，we ask the question：what is the impact of the tax-plan-oriented administration on corporate tax burden at the firm level? We answer this question by examining a sample of companies listed on China's A-share market from 2003 to 2016. We find that the tax burdens of individual firms in China exhibit a form of rigidity in that tax expenditures decrease at a significantly lower rate when sales revenue decreases than the rate at which they increase when sales revenue increases. Tax rigidity is manifested in both the Value Added Tax（VAT）and
Corporate Income Tax（CIT）burdens which constitute the majority of firms’ tax burdens in China. Further research shows that tax rigidity mainly exists for firms in the provinces where the annual tax revenue targets are just achieved or well exceeded，and is more pronounced for firms in the provinces where tax collections are strictly enforced. In addition，we find that tax rigidity mainly exists in the firms with heavy tax burdens. Our findings are useful for understanding the reality of corporate tax burden in China and improving the current economic policies dubbed as “Tax Cuts and Fee Reductions”for enterprises.本文受到国家自然科学基金项目“中国企业税负刚性研究——表现、形成机制与经济后果”（71702199）、“关联持股下的代理问题研究：股东合谋与堑壕防御视角”（71502181）、“制度变革、非正式制度因素与会计审计行为研究”（71790602）、“事务所规模与审计质量：团队视角”（71672159），中山大学高校基本科研业务费专项资金项目“儒家文化氛围影响高管行为决策吗？基于中国上市公司的机制与经验分析”（18WKPY15），广州市哲学社科规划 2019 年度课题“粤港澳大湾区创新驱动战略的保障机制研究——地市税收留成与制造业创新”（2019GZYB05），厦门国家会计学院云顶课题“国际税收新形势下我国与‘一带一路’沿线国家税收协定的框架理论研究”（YD20180303）的资助