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Ownership Structure,Tunneling,and Innovation Output:Evidence from Chinese Manufacturing-Industry Listed Firms
No full text钟腾，对外经济贸易大学金融学院副教授，经济学博士；汪昌云，中国人民大学中国财政金融政策研究中心教授、博士生导师，经济学博士；李宗龙，中证金融研究院助理研究员，经济学博士。【中文摘要】改善微观企业创新激励对于加快我国经济转型和结构调整至关重要。以2003—2017年中国制造业上市公司为研究样本，可使用公司三类专利申请数量和授权数量衡量企业创新产出。研究发现集中型股权结构会显著抑制企业专利创新产出,关联交易是二者之间的中介变量。由于隧道效应成本远低于研发创新成本,大股东倾向于通过隧道效应掠夺中小股东利益而非通过创新获得长期收益。此外,集中型股权结构会损害公司价值，且对于高科技企业的损害作用更大。政策建议为倡导多元化的股权结构，包括引进与培育能与控股股东抗衡的其他大股东、增加机构投资者持股等。
【Abstract】 Improving the innovation incentives of firms is essential for accelerating Chinas economic transformation and structural adjustment. This article takes the Chinese manufacturing-industry listed companies in 2003-2017 as the research sample and uses the quantity of three types of patent applications and the quantity of patents granted to measure the innovation output of firms. It is found that the concentrated ownership structure can significantly inhibit the output of patent innovation ，and that related party transactions are the mediating variable between them. Since the cost of tunneling is much lower than that of R&D and innovation，large shareholders tend to appropriate minority shareholders through tunneling rather than reap long-term benefits through innovation. In addition，the concentrated ownership structure will damage the value of a firm，and it will do more harm to high - tech companies. The policy implication is to advocate a diversified ownership structure，including introducing and cultivating other large shareholders who can compete with the controlling shareholder， and increasing the shareholdings of institutional investors.国家自然科学基金青年项目“房价膨胀的资源重配效应、企业创新与经济绩效：理论和微观实证”(71703018);国家自然科学基金面上项目“信念、投资者卖出行为与处置效应”（71874194)；中央高校基本科研业务费专项资金资助项目“房地产价格对微观企业行为影响研究”（16QD20
ULK1 phosphorylates Exo70 to suppress breast cancer metastasis
Get PDF乳腺癌是威胁女性生命健康的“头号杀手”，而远处转移是乳腺癌患者死亡的主要原因。因此，了解乳腺癌如何发动侵袭和转移，对于有效治疗乳腺癌、延长病人生存期具有重要意义。本研究中，该团队发现ULK1通过结合并磷酸化胞泌蛋白复合体关键亚基Exo70来抑制乳腺癌转移。ULK1对Exo70上Ser47，Ser59和Ser89位点的磷酸化，严重地削弱了Exo70的自身寡聚化和与其它胞外分泌复合体亚基的结合，进而减少了细胞运动伪足形成以及基质金属蛋白酶的分泌，从而抑制乳腺癌细胞的迁移和侵袭。该论文首次揭示了胞外分泌复合体重要成员Exo70在乳腺癌中受到ULK1和ERK1/2的双重磷酸化调控，从而使得乳腺癌细胞可以根据外环境来决定潜伏还是发动侵袭转移，为乳腺癌的治疗提供了新的理论基础。
本论文的通讯作者为占艳艳副教授、郭巍教授和胡天惠教授。医学院博士生毛丽媛、占艳艳副教授、吴斌博士和医学院博士生于强为共同第一作者。【Abstract】Increased expression of protein kinase ULK1 was reported to negatively correlate with breast cancer metastasis. Here we report that ULK1 suppresses the migration and invasion of human breast cancer cells. The suppressive effect is mediated through direct phosphorylation of Exo70, a key component of the exocyst complex. ULK1 phosphorylation inhibits Exo70 homo-oligomerization as well as its assembly to the exocyst complex, which are needed for cell protrusion formation and matrix metalloproteinases secretion during cell invasion. Reversely, upon growth factor stimulation, Exo70 is phosphorylated by ERK1/2, which in turn suppresses its phosphorylation by ULK1. Together, our study identifies Exo70 as a substrate of ULK1 that inhibits cancer metastasis, and demonstrates that two counteractive regulatory mechanisms are well orchestrated during tumor cell invasion.This work was supported by the grants from the National Natural Science Foundation of China (81572589, U1405228, 81472568, and 31770860), the Natural Science Foundation of Fujian grant (2017J06020, 2018J01400, 2017R1036-4, 2017R1036-6, 2016R1034-1, and 2016R1034-4), and the Xiamen Science and Technology grant (3502Z20159013) to Y.-y.Z. and T.H., and National Institute of Health R01 GM111128 to W.G.该论文的研究成果是在国家自然科学基金和福建省基金的资助下，与美国宾夕法尼亚大学和清华大学共同协作完成的
Intratumoral Delivery of a PD-1-blocking scFv encoded in Oncolytic HSV-1 Promotes Antitumor Immunity and Synergizes with TIGIT Blockade
Get PDF恶性肿瘤已严重威胁人类健康和生命，现有的治疗手段远远未能满足临床需求。厦门大学研究团队联合浙江养生堂生物科技有限公司、养生堂有限公司进行协同攻关，研制出新一代肿瘤免疫治疗药物——“注射用重组人PD-1抗体单纯疱疹病毒”。研究发现，重组表达PD-1单链抗体的溶瘤病毒具有“双药合一”抗肿瘤的突出优势，提高肿瘤治愈率。相关成果于2020年3月3日以研究论文形式在线发表于Cancer Immunology Research（《癌症免疫学研究》）期刊，为指导新型溶瘤病毒的升级改造和突破肿瘤免疫耐受提供了新的思路，为重组表达PD-1单链抗体的溶瘤病毒药物运用于肿瘤临床治疗奠定了坚实的理论基础。
厦门大学公共卫生学院夏宁邵教授和黄承浩助理教授为该论文的共同通讯作者，博士生林超龙和任文峰为该论文的共同第一作者。【Abstract】Oncolytic virotherapy can lead to systemic antitumor immunity, but the therapeutic potential of oncolytic viruses (OVs) in humans is limited due to their insufficient ability to overcome the immunosuppressive tumor microenvironment (TME). Here, we showed that locoregional oncolytic virotherapy upregulated the expression of PD-L1 in the TME, which was mediated by virus-induced type I and type II interferons (IFNs). To explore PD-1/PD-L1 signaling as a direct target in tumor tissue, we developed a novel immunotherapeutic herpes simplex virus (HSV), OVH-aMPD-1, that expressed a single-chain variable fragment (scFv) against PD-1 (aMPD-1 scFv). The virus was designed to locally deliver aMPD-1 scFv in the TME to achieve enhanced antitumor effects. This virus effectively modified the TME by releasing damage associated molecular patterns (DAMPs), promoting antigen cross-presentation by dendritic cells, and enhancing the infiltration of activated T cells; these alterations resulted antitumor T cell activity which led to reduced tumor burdens in a liver cancer model. Compared with OVH, OVH-aMPD-1 promoted the infiltration of myeloid-derived suppressor cells (MDSCs),resulting in significantly higher percentages of CD155+ G-MDSCs and M-MDSCs in tumors. In combination with TIGIT blockade, this virus enhanced tumor-specific immune responses in mice with implanted subcutaneous tumors or invasive tumors. These findings highlighted that intratumoral immunomodulation with an OV expressing aMPD-1 scFv could be an effective standalone strategy to treat cancers or drive maximal efficacy of a combination therapy with other immune checkpoint inhibitors.This work was supported by grant 2018ZX10301404-001-002 from the National Science and Technology Major Project and grant 81571990 from the National Natural Science Foundation of China.该研究获得了国家自然科学基金、国家科技重大专项的资助
Effect of Nitrogen Content in Catalyst Precursor on Activity of FeN/C Catalyst for Oxygen Reduction Reaction
No full text采用热解法制备FeN/C催化剂，考察催化剂前驱体中氮含量对其氧还原活性的影响. 使用X射线衍射、比表面积和孔径分布测试、透射电子显微镜以及热重分析等方法对催化剂的结构、形貌及催化剂前驱体的热性质等进行表征，使用线性扫描伏安法对催化剂的氧还原活性进行测试. 结果表明，以1,10-菲啰啉为氮源，FeCl3为铁源，Black Pearl 2000为载体，催化剂前驱体中1,10-菲啰啉含量为20wt%，Fe含量为1wt %时，热处理制备所得催化剂粒子分布均匀，比表面积为824.48 m2·g-1，平均孔隙为10.58 nm，表面的氮元素含量为0.31wt%；并具有最好的氧还原催化活性.催化剂前驱体中氮源含量在热解过程中导致催化剂的比表面积、孔径结构及表面氮元素含量的变化是影响催化剂活性的关键因素.Non-noble metal catalysts with high activity and low cost have attracted increasing interest as potential catalysts for oxygen reduction reaction (ORR) to replace Pt-based catalysts. In this paper, the effect of nitrogen content in catalyst precursor on ORR activity of FeN/C catalyst was investigated by X-ray diffraction (XRD), Brunauer-Emmet-Teller (BET) surface area and pore size distribution measurements, transmission electron microscope (TEM), thermogravimetric analysis (TGA), and rotating disk electrode (RDE) techniques. The results show that the most active catalyst was obtained by pyrolysis in argon at 1050 °C with a catalyst precursor containing 20wt% 1,10-phenanthroline, 1wt% Fe and Black Pearl 2000. The particle size and distribution, BET surface area and pore size distribution, surface nitrogen content are key factors affecting the catalytic activity of catalyst. The difference in ORR activities may be explained by TGA data of catalyst precursors with different nitrogen contents, where the pyrolysis of catalyst precursor with phen/BP ratio of 20/80 resulted in weight loss of 28.1% at the temperature above 420 °C, which may generate most of the catalytic sites for ORR.国家自然科学基金（No. 21506041）、贵州省科学技术基金（黔科合JZ字[2015]2007号）、贵州省留学人员科技活动择优资助项目（黔人项目资助合同（2014）12号）、贵州师范大学资助博士科研项目资助作者联系地址：贵州师范大学化学与材料科学学院，贵州 贵阳 550000Author's Address: School of Chemistry and Materials Science, Guizhou Normal University, Guiyang 550000, China通讯作者E-mail：[email protected]
Highly parallel and efficient single cell mRNA sequencing with paired picoliter chambers
Get PDF单细胞转录组测序技术在单个细胞水平上对转录组进行高通量测序分析，从而揭示单个细胞内所有基因的表达情况，揭示细胞间的异质性，在发育生物学、免疫学、微生物学、神经科学、临床医学等领域有重要的应用前景。单细胞转录组测序的挑战在于如何高效地操控单个细胞，如何对大量的低拷贝数mRNA进行无偏倚扩增，如何避免背景游离mRNA的污染，以及如何同时对大量的单细胞进行并行测序以降低成本。化学化工学院杨朝勇教授课题组在高通量单细胞转录组测序新器件新方法研究方面取得重要进展.该工作由厦门大学、上海交通大学、美国斯坦福大学等多团队联合攻关完成。化学生物学系博士研究生张明霞、邹远和2011协同创新中心博士研究生许醒为论文的共同第一作者。ScRNA-seq has the ability to reveal accurate and precise cell types and states. Existing scRNA-seq platforms utilize bead-based technologies uniquely barcoding individual cells, facing practical challenges for precious samples with limited cell number. Here, we present a scRNA-seq platform, named Paired-seq, with high cells/beads utilization efficiency, cell-free RNAs removal capability, high gene detection ability and low cost. We utilize the differential flow resistance principle to achieve single cell/barcoded bead pairing with high cell utilization efficiency (95%). The integration of valves and pumps enables the complete removal of cell-free RNAs, efficient cell lysis and mRNA capture, achieving highest mRNA detection accuracy (R = 0.955) and comparable sensitivity. Lower reaction volume and higher mRNA capture and barcoding efficiency significantly reduce the cost of reagents and sequencing. The single-cell expression profile of mES and drug treated cells reveal cell heterogeneity, demonstrating the enormous potential of Paired-seq for cell biology, developmental biology and precision medicine.The authors thank the National Science Foundation of China (21927806, 21735004, 21521004, 21325522), the National Key R&D Program of China (2018YFC1602900), Innovative research team of high-level local universities in Shanghai, and the Program for Changjiang Scholars and Innovative Research Team in University (IRT13036) for their financial support.该研究工作得到国家重大科研仪器研制项目、国家基金委重点项目、创新研究群体项目等支持
《会饮篇》
No full text厦门大学图书馆“人文社科实验室” “学会活动”（190）
标题：《会饮篇》
主讲人：金文卓
厦门大学人文学院哲学系2019级中国哲学专业
内容：
在柏拉图的所有对话中，《会饮篇》所刻画的场景最为生动，充满艺术性和趣味性。这场会饮中，大咖云集，有哲学家苏格拉底、悲剧家阿伽通、喜剧家阿里斯托芬、医生厄里什马克以及诡辩派修辞家斐德罗和泡赛尼阿斯以及闯进来的少年政治家亚尔西巴德。他们共同发表对爱神的颂词。不过，这场发言并不是以现场直播的方式展现，而是结束后的复盘。这种复盘无疑是暗含审视和选择的。这些发言遵循共同的主题，内容却不尽相同。虽然这些人身份各异，但共同参与了一场爱情学问的攀登。然而，我们必须时刻谨慎去对待他们各自的颂词，并考察他们的哲学式论述。攀登同样意味着跌落，危险无处不在。
讲座系列： 哲学系硕博学术沙龙 第104场
时间：2020年1月5日（星期日），晚上20：00点
地点：厦门大学图书馆三楼 321讲
A Study of Juzi's Beijing Travel Expenses and Government Subsidies in the Song Dynasty
No full text【中文摘要】宋代举子赴京赶考的费用，最低相当于一个人十个月的生活费用。而最高者,则相当于一个人两年半的生活费用。高昂的赴京旅费是困扰宋代举子的一个重要生活问题。从北宋太祖朝至南宋初期，政府断断续续对特定地区如四川、两广、福建的举子发放驿券、口券，借此资助他们入京赴试。南宋以后,特别是在宋理宗一朝，或由政府筹资，或由官民合资,贡士庄、贡士库普遍植立，从而在制度上保证了举子有稳定的旅费来源。但围绕着贡士庄的产权、承佃权的纷争，政府与地方不同的利益群体之间，对于创建贡士庄这类地方公益事业意见分歧。有关贡士庄的利弊之争，逐渐成为士人空间讨论的话题。
【Abstract】Juzi's (candidates for the imperial examinations) travel expenses for the examinations in Beijing were generally equivalent to 10 months of living expenses for an individual. In some cases，the travel expenses could be as high as 2.5 years of living expenses.The high travel expenses were a heavy financial burden on Juzi in the Song dynasty.From the early Northern Song to the early Southern Song dynasty，as a form of subsidy，the government intermittently issued coupons for travel and food expenses to Juzi in specific regions， including Sichuan，Guangdong， Guangxi and Fujian. After the Southern Song dynasty，especially during the reign of Song Lizong (1205-1264)， Gongshizhuang and Gongshiku， both forms of educational funds，were established either by the government or by governmental-private joint ventures，thus ensuring a stable source of funds to cover travel expenses for Juzi in the system. However，disputes over the property rights and tenancy rights of Gongshizhuang，which were usually local public welfare undertakings，persisted between the government and different local interest groups. The dispute over the pros and cons of Gongshizhuang gradually became a topic of discussion among scholars.钱建状，厦门大学人文学院教授、博士生导师，文学博士
Research Progress in Ethane Dehydrogenation to Cogenerate Power and Value-Added Chemicals in Solid Oxide Fuel Cells
No full text天然气/页岩气供应大幅增加推动了全球由乙烷制取乙烯等增值化学品的发展,深刻改变着石化产业的格局,乙烷高效清洁地转化为更高价值化学品具有深远意义. 乙烷蒸汽裂解制乙烯是一项比较成熟的工业生产技术,但是这一过程存在耗能高、积碳严重、热力学平衡受限等问题. 电能-增值化学品共生固体氧化物燃料电池由于可以将燃料气自发反应转化为高价值化学品的同时释放电能的特点被广泛研究. 本文总结了采用共生固体氧化物燃料电池将乙烷电化学脱氢共生乙烯增值化学品和电能的最新研究进展,重点介绍了固体氧化物燃料电池在乙烷脱氢中的工作原理和优势以及电解质和电极材料的选择等方向的研究发展,表明通过燃料电池技术低能耗实现乙烷共生乙烯增值化学品与电能具有显著的优越性,在实现高效节能的工业化生产中具有非常巨大的应用潜力.Increasing supplies of methane/shale gas have promoted global development of higher value chemicals such as ethylene production by ethane, which dramatically changes the markets of petrochemical industry. Clean and efficient transformation of ethane into higher value chemicals has far-reaching significance. Ethylene production through ethane steam cracking is a relatively matured technology for industrial production. However, the process consumes large amounts of energy and the presence of carbon deposition becomes a serious problem which is difficult to be solved. The cogenerated energy-chemicals solid oxide fuel cells have been widely studied because fuel gas can be converted into high-value chemicals via spontaneous reaction while releasing electrical energy. This paper summarizes the latest research progress in the electrochemical dehydrogenation of ethylene and electrical energy by using cogeneration solid oxide fuel cells, focusing on the mechanism and advantages of solid oxide fuel cells in ethane dehydrogenation, and the selections of electrolytes and electrode materials. It is demonstrated that the fuel cell technology has apparent advantages of realizing ethane symbiosis in ethylene production and electric energy generation with low energy consumption, and has great application potentials in the industrial production with high efficiency and energy saving.国家自然科学基金项目(NO.21975163)通讯作者:符显珠E-mail:[email protected]:FUXian-zhuE-mail:[email protected]深圳大学材料学院,广东 深圳 518060College of Material Science and Engineering, Shenzhen University, Shenzhen 518060, Guangdong, Chin
Preparation of α-Hydroxylated Acetal from 2-Butanone by Indirect Electrooxidation
No full text在板框式循环电解槽中,以KOH为电解质,KI为催化剂,石墨电极分别为阳极和阴极,研究电化学间接氧化2-丁酮合成乙偶姻中间体α-羟基缩酮,讨论电流密度、极板间电解液流速、电解液中2-丁酮浓度、电解温度以及通电量等电解条件对中间体收率和电流效率的影响,经优选工艺条件为：电流密度40 mA·cm-2,流速6.4 cm·s-1,2-丁酮浓度1.75 mol·L-1,电解温度30℃,通电量为1.5 F·moL-1时,中间体收率可达78.9%,电流效率40.1%. 循环伏安测试结果表明,电解时碘离子在阳极氧化生成碘单质,甲醇在阴极还原生成甲氧基负离子,原料2-丁酮与电解产物反应,并最终生成乙偶姻中间体.Acetoin (3-hydroxy-2-butanone) is an important food spice. As a platform compound, it is widely used in medicine, tobacco, cosmetics, chemical material and other industries. In this paper, α-hydroxylated acetal, an intermediate of acetoin, was prepared from 2-butanone by indirect electrooxidation in the plate and frame electrolytic cell, in which graphite plates were used as both an anode and a cathode, while KOH as an electrolyte and KI as a catalyst. Acetoin could be prepared by hydrolysis in acidic aqueous solution from acetoin intermediate. The effects of current density, electrolyte flow rate between the plates, 2-butanone concentration and electrolysis temperature on the yield and efficiency of acetoin intermediate were investigated. Under the optimized conditions, namely, the current density of 40 mA·cm-2, the flow rate of 6.4 cm·s-1, the 2-butanone concentration of 1.75 mol·L-1, the electrolysis temperature of 30 °C, and the passed charge of 1.5 F·mol-1, the yield and current efficiency of the acetoin intermediate could reach 78.9% and 40.1%, respectively. The cyclic voltammetric tests showed that during electrolysis, iodine ions were oxidized to iodine on the anode, while methanol was reduced to methoxy anion on the cathode. 2-butanone reacted with the electrolytic products, and eventually, the acetoin intermediate was formed.国家重点研发计划项目（No.2017YFB0307502）资助通讯作者:张新胜E-mail:[email protected]:ZHANGXin-shengE-mail:[email protected]华东理工大学化学工程国家重点实验室,上海 200237State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, Chin
Poly(ethylene oxide) Based Polymer Electrolytes for All-Solid-State Li-S Batteries
No full text锂硫电池由于具有高的理论比能量引起了广泛关注,然而传统液态锂硫电池由于多硫化物的“穿梭效应”以及安全问题而限制了其应用,全固态锂硫电池可显著提高电池安全性能并有望解决多硫化物的穿梭问题. 本文采用传统的溶液浇铸法制备了具有不同的[EO]/[Li+]的PEO-LiTFSI聚合物电解质,并将其应用于锂硫电池. 研究发现,虽然[EO]/[Li+] = 8的聚合物电解质具有更高的离子电导率,但是[EO]/[Li+] = 20的电解质与金属锂负极间的界面阻抗更低,界面稳定性更好. Li|PEO-LiTFSI([EO]/[Li+]=20)|Li对称电池在60 °C,电流密度为0.1 mA·cm-2时可稳定循环超过300 h,而Li|PEO-LiTFSI ([EO]/[Li+]=8)|Li对称电池循环75 h就出现了短路现象. 基于PEO-LiTFSI([EO]/[Li+]=20)电解质的锂硫电池首圈放电比容量为934 mAh·g-1,循环16圈后放电比容量为917 mAh·g-1以上. 而基于PEO-LiTFSI ([EO]/[Li+]=8)电解质的锂硫电池,由于与锂负极较低的界面稳定性不能够正常循环,首圈就出现了严重过充现象.In recent years, research on lithium-sulfur (Li-S) batteries has received much attention because the sulfur positive electrode and the lithium metal negative electrode produce a high theoretical specific capacity (lithium metal ~ 3800 mAh·g-1, sulfur ~ 1675 mAh·g-1). In addition, sulfur is considered to be the most promising cathode material for secondary lithium batteries, due to its advantages of low price and environmental friendly. However, the practical application of conventional liquid Li-S batteries is still obstructed by several critical issues, such as lithium ploysulfides shuttle effect, long-term stability of lithium metal anode with organic liquid electrolytes, and the safety concerns related to the lithium anode and liquid electrolyte. All-solid-state Li-S batteries using solid state electrolytes are considered as one of the most promising techniques to address the safety challenges of lithium ion batteries. Herein poly(ethylene oxide) (PEO)-based solid polymer electrolytes were prepared and investigated as electrolyte membranes for all-solid-state Li-S batteries. PEO/LiTFSI polymer electrolytes with different [EO]/[Li+] ratios were prepared and applied to Li-S batteries. It is found that although the PEO/LiTFSI ([EO]/[Li+] = 8) electrolyte had higher ionic conductivity, the PEO/LiTFSI ([EO]/[Li+] = 20) electrolyte resulted in lower interfacial resistance and higher interfacial stability with lithium anode. The Li|PEO/LiTFSI ([EO]/[Li+] = 20) |Li symmetric cell exhibited very stable voltage evolution without obvious erratic values or Li infiltration even being cycled for over 300 h at 60 °C and current density of 0.1 mA·cm-2. However, the PEO/LiTFSI ([EO]/[Li+] = 8) based one failed due to intern short circuit after being cycled for less than 75 h. The polymer Li-S cells comprising PEO/LiTFSI ([EO]/[Li+] = 20) electrolyte delivered a high first discharge capacity of 934 mAh·g-1 and good cycling stability with a capacity retention of 917 mAh·g-1 after 16 cycles at 60 oC. In contrast, the PEO/LiTFSI ([EO]/[Li+] = 8) electrolyte based cell was not able to be charged normally and severe overcharge occurred even at the first cycle due to the poor interfacial stability of PEO/LiTFSI ([EO]/[Li+] = 8) electrolyte with lithium anode.国家自然科学基金项目（No.21875196，No.21761132030，No.U1732121）、福建省引导性计划项目（No.2019H0003）和厦门大学大学生创新创业训练计划项目（No.2017X0280）资助通讯作者:龚正良E-mail:[email protected]:GONGZheng-liangE-mail:[email protected]厦门大学能源学院,福建 厦门 361005College of Energy, Xiamen University, Xiamen 361005, Fujian, Chin