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对一种口腔锥形束CT的有效剂量的估算

中华放射医学与防护杂志 2017年第3期37卷 222-225页

作者：罗葳赵越王建超北京大学人民医院口腔科 100044 中国疾病预防控制中心辐射防护与核安全医学所核应急中国预防控制中心重点实验室北京100008

目的从测量一种口腔锥形束CT（CBCT）扫描机的剂量面积乘积（DAP），使用一个转换系数估算有效剂量。方法使用DAP测量方法对一台柯达（KODAK）9500扫描机使用2个视野：16cm×15cm和12cm×8cm。将一台瑞典RTI产DAP（Doseguard 100）仪器... 详细信息

目的从测量一种口腔锥形束CT（CBCT）扫描机的剂量面积乘积（DAP），使用一个转换系数估算有效剂量。方法使用DAP测量方法对一台柯达（KODAK）9500扫描机使用2个视野：16cm×15cm和12cm×8cm。将一台瑞典RTI产DAP（Doseguard 100）仪器配套透射电离室贴在机器X射线管出线口处测量每种曝光方案的DAP值（mGy·am2），所有测量重复3次取平均。引用文献中一个转换系数为0．080μSv／mGy·cm2对柯达扫描机，每一个平均DAP值估算有效剂量。结果对于KODAK9500机器在2个视野的DAP值变化范围从512到1083mGy·cm2和用0．080μSv／mGy·cm2估算有效剂量从41到87μSv。发现与文献中3台KODAK9500机器有效剂量相比，本研究得到的有效剂量明显偏低。结论发现对口腔CBCT扫描机进行DAP测量是一种很好定义和快捷测量的方法，通过选择一个适当转换系数可以估算有效剂量。然而，对不同类型口腔CBCT机器如何适当地选用转换系数，需要进一步加以细致地研究。

关键词：锥形束计算机体层摄影剂量面积乘积有效剂量转换系数

Harnessing the Streptomyces-originating type I-E CRISPR/Cas system for efficient genome editing in Streptomyces

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Science China Life Sciences 2025年

作者： yuhui Xie Xiaoyan Liu Tingting Wu yunzi luo Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education) School of Chemical Engineering and TechnologyTianjin University Department of Gastroenterology State Key Laboratory of BiotherapyWest China HospitalSichuan University Georgia Tech Shenzhen Institute Tianjin University Haihe Laboratory of Sustainable Chemical Transformations

Since their discovery,CRISPR/Cas systems have significantly expanded the genetic toolbox,aiding in the exploration and enhanced production of natural products across various *** these,class 2 CRISPR/Cas systems are simpler and more broadly used,but they frequently fail to function effectively in many Streptomyces *** this study,we present an engineered class 1 type I CRISPR/Cas system derived from Streptomyces avermitilis,which enables efficient gene editing in phylogenetically distant Streptomyces *** a plasmid interference assay,we identified the effective protospacer adjacent motif as 5′-AAN-3′.Utilizing this system,we achieved targeted chromosomal deletions ranging from 8 bp to 100 kb,with efficiencies exceeding 92%.We further utilized this system to insert DNA fragments into different Streptomyces genomes,facilitating the heterologous expression of exogenous genes and the activation of endogenous natural product biosynthetic gene ***,we established a type I CRISPR/Cas-based gene-editing methodology that significantly advances the exploration of Streptomyces,known for their rich natural product *** is the first report of a gene editing tool developed based on the endogenous class 1 type I CRISPR/Cas system in Streptomyces *** work enriches the Streptomyces gene manipulation toolbox and advances the discovery of valuable natural products within these organisms.

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High-dimensional large-scale mixed-type data imputation under missing at random

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Science China Mathematics 2025年

作者： Wei Liu Guizhen Li Ling Zhou Lan luo School of Mathematics Sichuan University Center of Statistical Research and School of Statistics Southwestern University of Finance and Economics Department of Statistics and Actuarial Science University of Iowa

Missingness in mixed-type variables is commonly encountered in a variety of areas. The requirement of complete observations necessities data imputation when a moderate or large proportion of data is ***, inappropriate imputation would downgrade the performance of machine learning algorithms, leading to bad predictions and unreliable statistical inference. For high-dimensional large-scale mixed-type missing data, we develop a computationally efficient imputation method, missing value imputation via generalized factor models（MIG）, under missing at random. The proposed MIG method allows missing variables to be of different types,including continuous, binary, and count variables, and are scalable to both data size n and variable dimension p while existing imputation methods rely on restrictive assumptions such as the same type of missing variables,the low dimensionality of variables, and a limited sample size. We explicitly show that the imputation error of the proposed MIG method diminishes to zero with the rate Op(max{n-1/2, p-1/2}) as both n and p tend to infinity. Five real datasets demonstrate the superior empirical performance of the proposed MIG method over existing methods that the average normalized absolute imputation error is reduced by 5.3%–34.1%.

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Synergistically enhanced ORR and HER performance on Co-N-C coupled in-situ generated PtCo intermetallic

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Journal of Energy Chemistry 2025年第1期100卷 721-729页

作者： Guanyu luo Min Song Lulu An Xiao Huang Qian Zhang Chenhao Zhang Tao Shen Shuang Wang Deli Wang Key Laboratory of Material Chemistry for Energy Conversion and Storage (Huazhong University of Science and Technology) Ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology

Integrating multi-scale sites in a composite catalyst is vital to realize efficient ***,a synergistic composite catalyst consisting of Co atomic sites and in-situ generated PtCo intermetallic compounds （IMCs）(o-PtCo@CoNC) is proposed through Co pre-anchoring and subsequent impregnation-reduction *** loading of Co atoms provides a chance for in-situ generating PtCo ordered intermetallic *** remaining Co single atoms and PtCo IMCs construct synergistic electrocatalytic *** from the ordered structure,synergistic effect of Pt Co IMCs and Co single atoms,o-PtCo@CoNC exhibits excellent electrocatalytic performance for oxygen reduction reaction （ORR） and hydrogen evolution reaction （HER） with mass activity of 1.21 A mgPt-1（at 0.9 V） and5.70 A mgPt-1（at an overpotential of 100 mV）,***,o-PtCo@CoNC delivers negligible loss of half-wave potential and overpotential during long-term stability test in acid solutions,with 13 mV decay after 50,000 potential cycles for ORR and a 2.7 mV decay after 20,000 potential cycles for *** integration strategy of single-atomic sites coupled IMCs paves the way for enhancing the activity and durability of Pt-based electrocatalysts.

关键词： Synergistic effect Intermetallics Single atomic sites Oxygen reduction reaction Hydrogen evolution reaction

急性缺血性脑卒中不对称皮质静脉动态变化与神经功能预后的关系研究

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国际医学放射学杂志 2022年第1期 112-113页

作者： X.Lu y.luo M.Fawaz C.Zhu C.Chai G.Wu 李鹏飞

摘要急性缺血性脑卒中（AIS）的脑氧合与神经功能密切相关，并可采用定量磁化率图（QSM）对不对称显影的皮质静脉（APCV）进行无创测量。目的利用QSM量化AIS病人

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Construction of 3D porous Cu_(1.81)S/nitrogen-doped carbon frameworks for ultrafast and long-cycle life sodium-ion storage

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 191-200页

作者： Chen Chen Hongyu Xue Qilin Hu Mengfan Wang Pan Shang Ziyan Liu Tao Peng Deyang Zhang yongsong luo Key Laboratory of Microelectronics and Energy of Henan Province Henan Joint International Research Laboratory of New Energy Storage TechnologyCollege of Physics and Electronic EngineeringXinyang Normal UniversityXinyang 464000China School of Physics and Electronic Engineering Nanyang Normal UniversityNanyang 473061China

Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific ***,the inferior intrinsic conductivity and large volume variation during sodiation-desodiation processes seriously affect its high-rate and long-cyde performance,unbeneficial for the application as fast-charging and long-cycling SIBs ***,the three-dimensional porous Cu_(1.81)S/nitrogen-doped carbon frameworks(Cu_(1.81)S/NC)are synthesized by the simple and facile sol-gel and annealing processes,which can accommodate the volumetric expansion of Cu_(1.81)S nanoparticles and accelerate the transmission of ions and electrons during Na^(+)insertion/extraction processes,exhibiting the excellent rate capability(250.6 mA·g^(-1)at 20.0 A·g^(-1))and outstanding cycling stability(70% capacity retention for 6000 cycles at 10.0 A·g^(-1))for ***,the Na-ion full cells coupled with Na_(3)V_(2)(PO_(4))_(3)/C cathode also demonstrate the satisfactory reversible specific capacity of 330.5 mAh·g^(-1)at 5.0 A·g^(-1)and long-cycle performance with the 86.9% capacity retention at 2.0 A·g^(-1)after 750 *** work proposes a promising way for the conversionbased metal sulfides for the applications as fast-charging sodium-ion battery anode.

关键词： copper sulfide nanoparticles porous carbon framework fast charging long-cycle performance sodium-ion full batteries

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二氧化碳移除技术研究进展与评述

气候变化研究进展 2023年第5期19卷 672-682页

作者：程伟罗勇曹龙丹利黄磊邓祥征中国科学院地理科学与资源研究所北京100101 清华大学地球系统科学系地球系统数值模拟教育部重点实验室全球变化研究院北京100084 浙江大学地球科学学院大气科学系杭州310027 中国科学院大气物理研究所中国科学院东亚区域气候-环境重点实验室北京100029 中国科学院大学北京100049

在工业化进程中,化石能源利用使大气中二氧化碳(CO_(2))浓度不断增加[1]。中国力争在2060年前实现碳中和,中国碳中和战略目标须使碳排放尽早达峰,并降低峰值[2]。当前国内外研究主要集中在“减少碳排放”的路径和手段,但对于碳中和目标... 详细信息

在工业化进程中,化石能源利用使大气中二氧化碳(CO_(2))浓度不断增加[1]。中国力争在2060年前实现碳中和,中国碳中和战略目标须使碳排放尽早达峰,并降低峰值[2]。当前国内外研究主要集中在“减少碳排放”的路径和手段,但对于碳中和目标的实现而言,在减少碳排放的同时,很大程度上需依赖于“增汇”,即增加对大气中CO_(2)的吸收[3-4]。CO_(2)移除已成为将温升控制在1.5℃以内目标不可或缺的重要手段[5]。《巴黎协定》间接引入了CO_(2)移除,并为CO_(2)移除的大规模应用预留政策空间,以期实现在碳排放和碳移除之间取得平衡。CO_(2)移除可用于补偿难以脱碳或降碳成本高的行业的碳排放。

关键词：碳中和间接引入碳排放二氧化碳温升控制战略目标化石能源碳成本

Effect of Ti Additions on Mechanical and Thermodynamic Properties of W-Ti Alloys: A First-principles Study

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 246-257页

作者： ZHANG Jian NIE Wei HUANG Jin ZHU Ke LIU Ruxia ZHANG Ruizhi luo Guoqiang SHEN Qiang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China

The mechanical and thermodynamic properties of W-Ti alloys(including W_(15)Ti_(1),W_(14)Ti_(2),W_(12)Ti_(4) and W_(8)Ti_(8) alloys)were investigated by the first-principles approach based on density functional *** results indicate that W-Ti alloys except W_(8)Ti_(8) are thermodynamically *** modulus and hardness of W-Ti alloys are smaller than those of pure tungsten and gradually decrease with increasing Ti ***,their B/G ratios and Poisson's ratios exceed those of pure tungsten,suggesting that the introduction of Ti decreases the mechanical strength while enhancing the ductility of W-Ti *** thermal expansion coefficients for W-Ti alloys all surpass those of pure tungsten,indicating that the introduction of titanium exacerbates the thermal expansion behavior of W-Ti ***,elevated pressure has the capacity to suppress the thermal expansion tendencies in titanium-doped tungsten *** study offers theoretical insights for the design of nuclear materials by exploring the mechanical and thermodynamic properties of W-Ti alloys.

关键词： first-principles mechanical properties thermodynamic properties tungsten-titanium alloys

Innovative dual-mode device integrating capacitive desalination and solar vapor generation for high-efficiency seawater desalination

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Journal of Energy Chemistry 2025年第1期100卷 171-179页

作者： Jiacheng Wang Zhaoyu Chen Ruduan yuan Jiaxin luo Ben Zhang Keju Ji Meng Li Juanxiu Xiao Kuan Sun National Innovation Center for Industry-Education Integration of Energy Storage Technology MOE Key Laboratory of Low-grade Energy Utilization Technologies and SystemsCollege of Energy & Power Engineering Chongqing University Xuefeng Mountain Energy Equipment Safety National Observation and Research Station CQU-NUS Renewable Energy Materials & Devices Joint Laboratory Chongqing University Southwest Technology and Engineering Research Institute Jiangsu Provincial Key Laboratory of Bionic Functional Materials College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics State Key Laboratory of Marine Resources Utilization in South China Sea Collaborative Innovation Center of Marine Science and Technology School of Marine Science and Engineering Hainan University

Solar-driven interface evaporation with high solar-to-steam conversion efficiency has shown great potential in seawater ***,due to the influence of latent heat and condensation efficiency,the water yield from solar-driven interface evaporation remains insufficient,posing a significant challenge that requires *** this work,we designed a dual-mode high-flux seawater desalination device that combines solar-driven interface evaporation and capacitive *** utilizing coupled desalination materials exhibiting both photothermal conversion and capacitance activity,the device demonstrated photothermal evaporation rates of 1.41 and 0.97 kg m-2h-1for condensate water yield under one-sun ***,the device exhibited a salt adsorption capacity of up to48 mg g-1and a salt adsorption rate of 2.1 mg *** addition,the salt adsorption capacity increased by approximately 32% under one-sun ***,photo-enhanced capacitive desalination performance was explored through numerical simulations and theoretical *** calculations and characterizations confirmed that the defect energy levels formed by the introduction of sulfur vacancies can effectively widen the light absorption range,improve photothermal conversion performance,and stimulate more photoelectrons to participate in capacitive ***,the electron distribution state of molybdenum disulfide with sulfur vacancies and surface defect sites contributes to ion/electron transport at the solid-liquid *** work provides a novel pathway for integrating solar vapor generation with other low-energy desalination technologies.

关键词： Desalination