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Electron acceleration in a coil target-driven low-βmagnetic reconnection simulation

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Matter and Radiation at Extremes 2023年第6期8卷 30-40页

作者： jiacheng yu Jiayong Zhong Yongli Ping Weiming An Department of Astronomy and Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 100875China

Magnetic reconnection driven by a capacitor coil target is an innovative way to investigate low-βmagnetic reconnection in the laboratory,whereβis the ratio of particle thermal pressure to magnetic pressure.Low-βmagnetic reconnection frequently occurs in the Earth’s magnetosphere,where the plasma is characterized byβ≲0.01.In this paper,we analyze electron acceleration during magnetic reconnection and its effects on the electron energy spectrum via particle-in-cell simulations informed by parameters obtained from experiments.We note that magnetic reconnection starts when the current sheet is down to about three electron inertial lengths.From a quantitative comparison of the different mechanisms underlying the electron acceleration in low-βreconnection driven by coil targets,we find that the electron acceleration is dominated by the betatron mechanism,whereas the parallel electric field plays a cooling role and Fermi acceleration is negligible.The accelerated electrons produce a hardened power-law spectrum with a high-energy bump.We find that injecting electrons into the current sheet is likely to be essential for further acceleration.In addition,we perform simulations for both a double-coil co-directional magnetic field and a single-coil one to eliminate the possibility of direct acceleration of electrons beyond thermal energies by the coil current.The squeeze between the two coil currents can only accelerate electrons inefficiently before reconnection.The simulation results provide insights to guide future experimental improvements in low-βmagnetic reconnection driven by capacitor coil targets.

关键词： reconnection acceleration magnetic

安徽省工业水资源效率与经济发展水平耦合协调性分析

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河北环境工程学院学报 2024年第2期34卷 62-69页

作者：于佳程何刚安徽理工大学经济与管理学院安徽淮南232001

采用Super-SBM模型测算2012—2021年安徽16市工业水资源效率,从经济规模、经济潜力、经济活力三个维度构建经济发展水平评价指标体系,利用熵权-综合指数法计算其经济发展水平,引入耦合协调度模型探究工业水资源效率与经济发展水平间的关... 详细信息

采用Super-SBM模型测算2012—2021年安徽16市工业水资源效率,从经济规模、经济潜力、经济活力三个维度构建经济发展水平评价指标体系,利用熵权-综合指数法计算其经济发展水平,引入耦合协调度模型探究工业水资源效率与经济发展水平间的关系,并使用Dagum基尼系数分析其空间差异来源。结果表明:2012—2021年,安徽工业水资源效率呈上升趋势,一直处于无效状态,合肥一直处于超效状态,淮南不升反降;安徽工业水资源效率与经济发展水平耦合协调度由中度失调衰退型晋级到濒临失调衰退型,各城市耦合协调度均有上升,区域间发展不平衡;安徽耦合协调度总体基尼系数呈现下降趋势,皖中在地区内差异中占主导地位,地区内空间差异贡献最大。

关键词：工业水资源效率经济水平耦合协调基尼系数

Data-driven methods for discovery of next-generation electrostrictive materials

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npj Computational Materials 2022年第1期8卷 2393-2399页

作者： Dennis P.Trujillo Ashok Gurung jiacheng yu Sanjeev K.Nayak S.Pamir Alpay Pierre-Eymeric Janolin Department of Materials Science and Engineering and Institute of Materials Science University of ConnecticutStorrsCT06269USA X-Ray Science Division Argonne National LaboratoryLemontIL60439USA Department of Physics University of ConnecticutStorrsCT06269USA UniversitéParis-Saclay CentraleSupélecCNRSLaboratoire SPMS91190Gif-sur-YvetteFrance

All dielectrics exhibit electrostriction,i.e.,display a quadratic strain response to an electric field compared to the linear strain dependence of piezoelectrics.As such,there is significant interest in discovering new electrostrictors with enhanced electrostrictive coefficients,especially as electrostrictors can exhibit effective piezoelectricity when a bias electric field is applied.We present the results of a study combining data mining and first-principles computations that indicate that there exists a group of iodides,bromides,and chlorides that have electrostrictive coefficients exceeding 10 m^(4)C^(–2)which are substantially higher than typical oxide electrostrictive ceramics and polymers.The corresponding effective piezoelectric voltage coefficients are three orders of magnitude larger than lead zirconate titanate.

关键词： strict piezoelectric exceeding

Unveiling the geometric site dependent activity of spinel Co_(3)O_(4)for electrocatalytic chlorine evolution reaction

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Journal of Energy Chemistry 2024年第5期92卷 95-103页

作者： Linke Cai Yao Liu Jingfang Zhang Qiqi Jia jiacheng Guan Hongwei Sun yu yu Yi Huang Key Laboratory of Pesticide&Chemical Biology of Ministry of Education Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction of Ministry of EducationCollege of ChemistryCentral China Normal UniversityWuhan 430079HubeiChina Key Laboratory of Green Chemical Engineering Process of Ministry of Education Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of EducationHubei Key Laboratory of Novel Reactor and Green Chemical TechnologySchool of Chemical Engineering&PharmacyWuhan Institute of TechnologyWuhan 430205HubeiChina College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108FujianChina School of Chemistry and Chemical Engineering Anhui UniversityHefei 230601AnhuiChina

Spinel cobalt oxide(Co_(3)O_(4)),consisting of tetrahedral Co^(2+)(CoTd)and octahedral Co^(3+)(CoOh),is considered as promising earth-abundant electrocatalyst for chlorine evolution reaction(CER).Identifying the catalytic contribution of geometric Co site in the electrocatalytic CER plays a pivotal role to precisely modulate electronic configuration of active Co sites to boost CER.Herein,combining density functional theory calculations and experiment results assisted with operando analysis,we found that the Co_(Oh) site acts as the main active site for CER in spinel Co_(3)O_(4),which shows better Cl^(-)adsorption and more moderate intermediate adsorption toward CER than CoTd site,and does not undergo redox transition under CER condition at applied potentials.Guided by above findings,the oxygen vacancies were further introduced into the Co_(3)O_(4) to precisely manipulate the electronic configuration of Co_(Oh) to boost Cl^(-)adsorption and optimize the reaction path of CER and thus to enhance the intrinsic CER activity significantly.Our work figures out the importance of geometric configuration dependent CER activity,shedding light on the rational design of advanced electrocatalysts from geometric configuration optimization at the atomic level.

关键词： Chlorine evolution reaction Geometry effects Active chlorine Electronic configuration optimization Spinel oxides

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生物友好矿粉基免烧陶粒制备及性能研究

非金属矿 2024年第1期47卷 10-13页

作者：秦文彬王琴俞佳成韦丽敏李志涛张宇峰南京工业大学环境科学与工程学院江苏南京211800 江苏省宜裕环保科技有限公司江苏无锡214200

为提高生物亲和性矿粉在陶粒制备过程中的多元化应用,为水处理技术和过滤介质的改进提供参考和指导,本研究采用石英砂、沸石粉和火山石制备免烧陶粒,通过单因素分析确定初始原材料配比。结果表明,3种陶粒性能相近,但石英砂陶粒成本更低... 详细信息

为提高生物亲和性矿粉在陶粒制备过程中的多元化应用,为水处理技术和过滤介质的改进提供参考和指导,本研究采用石英砂、沸石粉和火山石制备免烧陶粒,通过单因素分析确定初始原材料配比。结果表明,3种陶粒性能相近,但石英砂陶粒成本更低。采用响应面法分析得出,当石英砂、低碱水泥、硅灰粉和木质纤维质量比为64∶36∶21∶6时,石英砂陶粒性能最优,含泥量为0.62%,空隙率为41.32%,磨损率为0.16%,筒压强度为3.52 MPa,比表面积为12.01 m^(2)/g。

关键词：人工陶粒滤料含泥量磨损率空隙率生物友好性

双循环背景下饲料企业复合型人才培养模式研究

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中国饲料 2023年第14期 162-165页

作者：余家成信阳艺术职业学院马克思主义学院河南信阳464000

随着劳动力和原料成本的持续上涨,以饲料企业为代表的传统加工制造业的成本优势已不再凸显,所以完备的产业链体系和巨大的创新潜能才是支撑饲料企业参与经济双循环的关键。而产业链体系和创新潜能都与人才要素息息相关,人才已成为饲料... 详细信息

随着劳动力和原料成本的持续上涨,以饲料企业为代表的传统加工制造业的成本优势已不再凸显,所以完备的产业链体系和巨大的创新潜能才是支撑饲料企业参与经济双循环的关键。而产业链体系和创新潜能都与人才要素息息相关,人才已成为饲料企业参与市场竞争的第一资源。为此,饲料企业要加强对人才的培养,特别是兼具创新精神、创新能力和饲料生产管理专业知识的复合型人才,以人才的创造性活动提高饲料企业的经济效益和市场竞争力,助力饲料企业的可持续发展。

关键词：双循环饲料企业复合型人才培养模式

Direct reprogramming of fibroblasts into functional hepatocytes via CRISPRa activation of endogenous Gata4 and Foxa3

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中华医学杂志(英文版) 2024年第11期137卷 2024 May 9页

作者： Li jiacheng Li Ruopu Bai Xue Zhang Wenlong Nie yu Hu Shengshou State Key Laboratory of Cardiovascular Disease Fuwai Hospital and Cardiovascular Institute National Center for Cardiovascular Diseases Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China Department of Obstetrics and Gynecology Beijing Advanced Innovation Center for Genomics Third Hospital School of Life Sciences Peking University Beijing China

Background: The ability to generate functional hepatocytes without relying on donor liver organs holds significant therapeutic promise in the fields of regenerative medicine and potential liver disease treatments. Clustered regularly interspaced short palindromic repeats (CRISPR) activator (CRISPRa) is a powerful tool that can conveniently and efficiently activate the expression of multiple endogenous genes simultaneously, providing a new strategy for cell fate determination. The main purpose of this study is to explore the feasibility of applying CRISPRa for hepatocyte reprogramming and its application in the treatment of mouse liver fibrosis.Method: The differentiation of mouse embryonic fibroblasts (MEFs) into functional induced hepatocyte-like cells (iHeps) was achieved by utilizing the CRISPRa synergistic activation mediator (SAM) system, which drove the combined expression of three endogenous transcription factors—Gata4,Foxa3, andHnf1a—or alternatively, the expression of two transcription factors,Gata4 andFoxa3.In vivo, we injected adeno-associated virus serotype 6 (AAV6) carrying the CRISPRa SAM system into liver fibroticCol1a1-CreER;Cas9fl/fl mice, effectively activating the expression of endogenousGata4 andFoxa3 in fibroblasts. The endogenous transcriptional activation of genes was confirmed using real-time quantitative polymerase chain reaction (RT-qPCR) and RNA-seq, and the morphology and characteristics of the induced hepatocytes were observed through microscopy. The level of hepatocyte reprogrammingin vivo is detected by immunofluorescence staining, while the improvement of liver fibrosis is evaluated through Sirius red staining, alpha-smooth muscle actin (α-SMA) immunofluorescence staining, and blood alanine aminotransferase (ALT) examination.Results: Activation of only two factors,Gata4 andFoxa3, via CRISPRa was sufficient to successfully induce the transformation of MEFs into iHeps. These iHeps could be expandedin vitro and displayed functional characteristics similar to those of mature hepatocyte

关键词： Liver fibrosis CRISPRa Cell reprogramming Transcriptional activation Hepatocytes

面向智能无人通信系统的因果性对抗攻击生成算法

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通信学报 2024年第1期45卷 54-62页

作者：禹树文许威姚嘉铖东南大学移动通信全国重点实验室江苏南京210096 网络通信与安全紫金山实验室江苏南京211111

考虑到基于梯度的对抗攻击生成算法在实际通信系统部署中面临着因果性问题,提出了一种因果性对抗攻击生成算法。利用长短期记忆网络的序列输入输出特征与时序记忆能力,在满足实际应用中存在的因果性约束前提下,有效提取通信信号的时序... 详细信息

考虑到基于梯度的对抗攻击生成算法在实际通信系统部署中面临着因果性问题,提出了一种因果性对抗攻击生成算法。利用长短期记忆网络的序列输入输出特征与时序记忆能力,在满足实际应用中存在的因果性约束前提下,有效提取通信信号的时序相关性,增强针对无人通信系统的对抗攻击性能。仿真结果表明,所提算法在同等条件下的攻击性能优于泛用对抗扰动等现有的因果性对抗攻击生成算法。

关键词：智能通信系统对抗攻击深度学习因果系统长短期记忆网络

Deficiency of betaine-homocysteine methyltransferase activates glucose-6-phosphate dehydrogenase(G6PD) by decreasing arginine methylation of G6PD in hepatocellular carcinogenesis

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Science China Life Sciences 2024年第8期 1648-1665页

作者： Jie Gao Xiaoyi Shi Yaohui Sun Xudong Liu Feng Zhang Chengcheng Shi Xiao yu Zhiping Yan Long Liu Shizhe yu jiacheng Zhang Xiaodan Zhang Shuijun Zhang Wenzhi Guo Department of Hepatobiliary and Pancreatic Surgery The First Affiliated Hospital of Zhengzhou University Henan Diagnosis & Treatment League for Hepatopathy The First Affiliated Hospital of Zhengzhou University Henan Innovative Research Group for Hepatobiliary & Pancreatic Surgery and Digestive Organ Transplantation Henan Organ Transplantation Quality Control Centre Henan Engineering Technology Research Center for Organ Transplantation Department of Pharmacy The First Affiliated Hospital of Zhengzhou University Department of General Surgery Huashan HospitalFudan University Cancer Metastasis Institute Fudan University

Betaine-homocysteine methyltransferase（BHMT） regulates protein methylation and is correlated with tumorigenesis;however,the effects and regulation of BHMT in hepatocarcinogenesis remain largely unexplored.Here,we determined the clinical significance of BHMT in the occurrence and progression of hepatocellular carcinoma（HCC） using tissue samples from 198 patients.BHMT was to be frequently found（86.6%） expressed at relatively low levels in HCC tissues and was positively correlated with the overall survival of patients with HCC.Bhmt overexpression effectively suppressed several malignant phenotypes in hepatoma cells in vitro and in vivo,whereas complete knockout of Bhmt(Bhmt-/-) produced the opposite effect.We combined proteomics,metabolomics,and molecular biological strategies and detected that Bhmt-/-promoted hepatocarcinogenesis and tumor progression by enhancing the activity of glucose-6-phosphate dehydrogenase（G6PD）and PPP metabolism in DEN-induced HCC mouse and subcutaneous tumor-bearing models.In contrast,restoration of Bhmt with an AAV8-Bhmt injection or pharmacological inhibition of G6PD attenuated hepatocarcinogenesis.Additionally,coimmunoprecipitation identified monomethylated modifications of the G6PD,and BHMT regulated the methylation of G6PD.Protein sequence analysis,generation and application of specific antibodies,and site-directed mutagenesis indicated G6PD methylation at the arginine residue 246.Furthermore,we established bidirectionally regulated BHMT cellular models combined with methylation-deficient G6PD mutants to demonstrate that BHMT potentiated arginine methylation of G6PD,thereby inhibiting G6PD activity,which in turn suppressed hepatocarcinogenesis.Taken together,this study reveals a new methylation-regulatory mechanism in hepatocarcinogenesis owing to BHMT deficiency,suggesting a potential therapeutic strategy for HCC treatment.

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