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Quantifying the effects of long-term news on stock markets on the basis of the multikernel Hawkes process

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Science China(Information Sciences) 2021年第9期64卷 44-56页

作者： xiao ding Jihao SHI Junwen DUAN bing qin ting liu Research Center for Social Computing and Information Retrieval

Recent studies have revealed that long-term financial news can affect stock markets. However,previous research mainly focuses on modeling the short-term effects of financial news and suffers from the weak ability of quantifying the time-decaying influence of financial news. To fill this gap, this study introduces the Hawkes process to estimate the time-decaying influence of long-term financial news. However, the performance of the conventional Hawkes process is sensitive to the choice of kernel functions. Hence, we propose a novel multikernel-powered Hawkes process framework, which uses multiple kernels to model different time-decaying rates, thus alleviating the instability of our proposed Hawkes process based prediction *** results show that the proposed framework yields state-of-the-art stock market prediction accuracies on 515 listed companies and gains more profits in market trading simulation compared with baseline methods. News-based stock prediction can complement studies on price-volume-based stock prediction.

关键词： Hawkes process multikernel function stock market prediction long-term news effects

Text Difficulty Study:Do Machines Behave the Same as Humans Regarding Text Difficulty?

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Machine Intelligence Research 2024年第2期21卷 283-293页

作者： Bowen Chen xiao ding Yi Zhao Bo Fu tingmao Lin bing qin ting liu Research Center for Social Computing and Information Retrieval Harbin Institute of TechnologyHarbin 150001China Fundamental Technology Center China Construction Bank Financial Technology Co.Ltd.Beijing 100033China

With the emergence of pre-trained models,current neural networks are able to give task performance that is comparable to ***,we know little about the fundamental working mechanism of pre-trained models in which we do not know how they approach such performance and how the task is solved by the *** example,given a task,human learns from easy to hard,whereas the model learns ***,difficulty-insensitive learning leads to great success in natural language processing(NLP),but little attention has been paid to the effect of text difficulty in *** propose a human learning matching index(HLM Index)to investigate the effect of text *** results show:1)LSTM gives more human-like learning behavior than ***,UID-SuperLinear gives the best evaluation of text difficulty among four text difficulty *** nine tasks,some tasks’performance is related to text difficulty,whereas others are not.2)Model trained on easy data performs best in both easy and medium test data,whereas trained on hard data only performs well on hard test data.3)Train the model from easy to hard,leading to quicker convergence.

关键词： Cognition inspired natural language processing psycholinguistics explainability text difficulty curriculum learning

Fabrication of azobenzene-functionalized porous polymers for selective CO_(2) capture

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Chinese Journal of Chemical Engineering 2022年第3期35卷 24-30页

作者： ding-Ming Xue Wen-Juan Zhang xiao-qin liu Shi-Chao Qi Lin-bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China

Many solid adsorbents have been prepared for the CO_(2)*** particular,the photoresponsive adsorbents have attracted extensive interests because of their tunable pore structure and variable responsive behaviors provoked by the external ***,it is challenging to fabricate the photoresponsive adsorbents featured the big CO_(2)capacity and high CO_(2)***,copolymerized between 4-phenylazobenzoyl chloride,2,4,6-trichloro-1,3,5-triazine and melamine,a series of azobenzenefunctionalized porous polymers(PTM-AZOs)are successfully *** PTM-AZOs are verified in possession of proper pore structures,large surface area and photoconductive properties through a series of *** PTM-AZO-2 with the trans-isomerization exhibits the best CO_(2)adsorption amount of 2.7 mmol·g^(-1)(273 K and 0.1 MPa),while the CO_(2)/N_(2)selectivity can reach 2459 and 607 on the trans-and cis-isomerization,*** regulatable pore structures controlled by the photoresponsive azobenzene groups affect the CO_(2)capture performance of the PTM-AZOs.

关键词： Adsorption CO_(2)capture Selectivity Azobenzene Photoresponse

Quantification of electron accumulation at grain boundaries in perovskite polycrystalline films by correlative infrared-spectroscopic nanoimaging and Kelvin probe force microscopy

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Light(Science & Applications) 2021年第5期10卷 890-897页

作者： ting-xiao qin En-Ming You Mao-Xin Zhang Peng Zheng xiao-Feng Huang Song-Yuan ding bing-Wei Mao Zhong-Qun Tian State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy MaterialsCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamenChina School of Aerospace Engineering Xiamen UniversityXiamenChina

Organic–inorganic halide perovskites are emerging materials for photovoltaic applications with certified power conversion efficiencies(PCEs)over 25%.Generally,the microstructures of the perovskite materials are critical to the performances of ***,the role of the nanometer-sized grain boundaries(GBs)that universally existing in polycrystalline perovskite films could be benign or detrimental to solar cell performance,still remains ***,nanometer-resolved quantification of charge carrier distribution to elucidate the role of GBs is highly ***,we employ correlative infrared-spectroscopic nanoimaging by the scattering-type scanning near-field optical microscopy with 20 nm spatial resolution and Kelvin probe force microscopy to quantify the density of electrons accumulated at the GBs in perovskite polycrystalline thin *** is found that the electron accumulations are enhanced at the GBs and the electron density is increased from 6×10^(19) cm^(−3 )in the dark to 8×10^(19) cm^(−3 ) under 10 min illumination with 532 nm *** results reveal that the electron accumulations are enhanced at the GBs especially under light illumination,featuring downward band bending toward the GBs,which would assist in electron-hole separation and thus be benign to the solar cell performance.

关键词： illumination polycrystalline grain

Implementing an“Impracticable”Copolymerization to Fabricate a Desired Polymer Precursor for N-doped Porous Carbons

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Engineering 2022年第9期16卷 154-161页

作者： Shi-Chao Qi xiao-Jie Lu Yin-Cong Lou Rui Zhou ding-Ming Xue xiao-qin liu Lin-bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Material(SICAM)College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China

It is common that a proof-of-concept of a desired reaction,which might generate materials with new functions or application potential,is eventually proved impracticable or commercially *** efforts have been made but wasted in searching for unknown reaction conditions in solvent environments because it was believed that the activity of reactants can be enhanced to facilitate reactions by dissolving them in ***,an abnormal case was discovered in this study.A desired copolymerization reaction between 1,3,5-tris(chloromethyl)-2,4,6-trimethylbenzene and melamine was confirmed to be impracticable under various solvent conditions;however,it was successfully implemented using a solvent-free *** first-principle calculations and molecular dynamics simulations,two decisive factors that the reaction in solvents cannot possess,namely the reaction equilibrium being pushed by the timely release of by-products and the confined thermal motions of the activated monomer molecules in the solid phase,were demonstrated to make the copolymerization successful in the solvent-free *** to the high aromaticity and azacyclo-content,the as-synthetic copolymer exhibited good application potential as a precursor to fabricate N-doped porous carbons with satisfactory carbon yields,ideal N contents,desired textural properties,and competitive CO_(2)capture abilities compared to other representative counterparts reported recently.

关键词： Solvent-free method Solvent effect Copolymerization N-doped porous carbon

An antiempirical strategy:sacrificing aromatic moieties in the polymer precursor for improving the properties of the derived N-doped porous carbons

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Green Chemical Engineering 2020年第1期1卷 70-76页

作者： Shi-Chao Qi ding-Ming Xue Guo-Xing Yu Rong-Rong Zhu xiao-qin liu Lin-bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Material(SICAM)College of Chemical EngineeringNanjing Tech UniversityNanjing211816China

With the carbonization at an elevated temperature,high aromaticity of a precursor for porous carbons was traditionally thought to be crucial for the resultant perfect textural properties and ideal application performances of the porous ***,many efforts have been done to search or to artificially prepare the polymer precursors with higher aromaticity to generate more satisfying porous ***,an antiempirical case was found in this *** copolymerization between 1,3,5-tris(chloromethyl)-2,4,6-trimethylbenzene(TCM)and cyclohexane-1,4-diamine was successfully implemented to get a polymer code-named NUT-40,in which half of the ring structures are nonaromatic,while N-doped porous carbons(NDPCs)with better textural properties(e.g.,SBET=1363 m^(2)g^(-1)for NDPC-600)and competitive CO_(2)capture abilities(e.g.,CO_(2)capacity=4.3 mmol g^(-1)at 25℃and 1 bar for NDPC-600)were generated from the NUT-40,compared with the NDPC counterparts derived from the NUT-4 in a previous study(e.g.,SBET=958 m^(2)g^(-1)and CO_(2)capacity=3.8 mmol g^(-1)at 25℃and 1 bar for NDPC-600),in which TCM and ursol were employed as the monomers instead,and thus the ring structures in the NUT-4 was fully *** first-principle and molecular dynamics simulations,it was demonstrated that the embryo pore structure in the NUT-40 molecule can be more easily maintained during the carbonization than that of the NUT-4,which finally improves the surface area and porosity of the NUT-40 generated NDPCs.

关键词： Copolymer Aromaticity Pyrolysis Carbon capture N-doped porous carbon

Global trend and future landscape of intestinal microcirculation research from 2000 to 2021:A scientometric study

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World Journal of Gastroenterology 2023年第9期29卷 1523-1535页

作者： Sun-Jing Fu Meng-ting Xu bing Wang bing-Wei Li Hao Ling Yuan Li qin Wang Xue-ting liu xiao-Yan Zhang Ai-Ling Li Ming-Ming liu Institute of Microcirculation Key Laboratory of MicrocirculationMinistry of HealthChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100005China Department of Radiology The Affiliated Changsha Central HospitalHengyang Medical SchoolUniversity of South ChinaChangsha 410004Hunan ProvinceChina Diabetes Research Center Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100005China

BACKGROUND The intestinal microcirculation functions in food absorption and metabolic substance *** evidence indicates that intestinal microcirculatory dysfunction is a significant source of multiple gastrointestinal *** date,there has not been a scientometric analysis of intestinal microcirculatory *** To investigate the current status,development trends,and frontiers of intestinal microcirculatory research based on bibliometric *** VOSviewer and CiteSpace 6.1.R2 were used to identify the overall characteristics and knowledge map of intestinal microcirculatory research based on the core literature published from 2000 to 2021 in the Web of Science *** characteristics of each article,country of origin,institution,journal,cocitations,and other information were analyzed and *** There were 1364 publications enrolled in the bibliometric analysis,exhibiting an upward trend from 2000 to 2021 with increased participation *** United States and Dalhousie University took the lead among countries and institutions,*** was the most prolific journal,and Nature Reviews Microbiology Clinical had the most *** topical hotspots and frontiers in intestinal microcirculatory research were centered on the pathological processes of functional impairment of intestinal microvessels,diverse intestinal illnesses,and clinical *** Our study highlights insights into trends of the published research on the intestinal microcirculation and offers serviceable guidance to researchers by summarizing the prolific areas in intestinal disease research to date.

关键词： Intestinal microcirculation Bibliometric analysis CiteSpace VOSviewer Visualization

Role of insulin in pancreatic microcirculatory oxygen profile and bioenergetics

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World Journal of Diabetes 2022年第9期13卷 765-775页

作者： bing-Wei Li Yuan Li Xu Zhang Sun-Jing Fu bing Wang xiao-Yan Zhang Xue-ting liu qin Wang Ai-Ling Li Ming-Ming liu Institute of Microcirculation Diabetes Research CenterChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100005China Laboratory of Electron Microscopy Ultrastructural Pathology CenterPeking University First HospitalBeijing 100005China

BACKGROUND The pancreatic islet microcirculation adapts its metabolism to cope with limited oxygen availability and nutrient *** diabetes,the balance between oxygen delivery and consumption is *** has been proven to exert complex actions promoting the maintenance of homeostasis of the pancreas under *** To test the hypothesis that insulin administration can improve the integrated pancreatic microcirculatory oxygen profile and *** The pancreatic microcirculatory partial oxygen pressure(PO_(2)),relative hemoglobin(rHb)and hemoglobin oxygen saturation(SO_(2))were evaluated in nondiabetic,type 1 diabetes mellitus(T1DM),and insulin-treated mice.A threedimensional framework was generated to visualize the microcirculatory oxygen *** changes in the microvasculature were examined using transmission electron *** Extracellular Flux Analyzer was used to detect the real-time changes in bioenergetics by measuring the oxygen consumption rate and extracellular acidification rate in islet microvascular endothelial cells(IMECs).RESULTS Significantly lower PO_(2),rHb,and SO_(2) values were observed in T1DM mice than in nondiabetic *** administration ameliorated the streptozotocin-induced decreases in these microcirculatory oxygen parameters and improved the mitochondrial ultrastructural abnormalities in *** profiling revealed that the IMECs did not have spare respiratory ***-treated IMECs exhibited significantly greater basal respiration than glucotoxicity-exposed IMECs(P<0.05).An energy map revealed increased energetic metabolism in insulin-treated IMECs,with significantly increased ATP production,non-mitochondrial respiration,and oxidative metabolism(all P<0.05).Significant negative correlations were revealed between microcirculatory SO_(2) and bioenergetic *** Glucotoxicity deteriorates the integrated pancreatic microcirculatory oxygen profil

关键词： Diabetes mellitus Glucotoxicity Endothelial cells Microcirculation Mitochondria Bioenergetics

Berberine potentizes apoptosis induced by X-rays irradiation probably through modulation of gap junctions

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Chinese Medical Journal 2011年第8期124卷 1221-1228页

作者： liu bing WANG qin YUAN Dong-dong HONG xiao-ting TAO Liang Department of Pharmacology Zhongshan School of Medicine SunYat-sen University Guangzhou Guangdong 510080 China

Background Clinical combination of some traditional Chinese medical herbs, including berberine, with irradiation is demonstrated to improve efficacy of tumor radiotherapy, yet the mechanisms for such effect remain largely unknown. The present study investigated the effect of berberine on apoptosis induced by X-rays irradiation and the relation between this effect and gap junction intercellular communication （GJIC）.Methods The role of gap junctions in the modulation of X-rays irradiation-induced apoptosis was explored by manipulation of connexin （Cx） expression, and gap junction function, using oleamide, a GJIC inhibitor, and *** In transfected HeLa cells, Cx32 expression increased apoptosis induced by X-rays irradiation, while inhibition of gap junction by oleamide reduced the irradiation responses, indicating the dependence of X-rays irradiation-induced apoptosis on GJIC. Berberine, at the concentrations without cytotoxicity, enhanced apoptosis induced by irradiation only in the presence of functional gap *** These results suggest that berberine potentizes cell apoptosis induced by X-rays irradiation, probably through enhancement of gap junction activity.

关键词： berberine gap junctions X-rays irradiation apoptosis