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Research on a Monte Carlo global variance reduction method based on an automatic importance sampling method

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Nuclear Science and Techniques 2024年第5期35卷 200-215页

作者： Yi-Sheng Hao zhen wu Shen-Shen Gao Rui Qiu Hui Zhang Jun-Li Li Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging of Ministry of Education Beijing 100084China Nuctech Company Limited Beijing 100084China

Global variance reduction is a bottleneck in Monte Carlo shielding *** global variance reduction problem requires that the statistical error of the entire space is *** study proposed a grid-AIS method for the global variance reduction problem based on the AIS method,which was implemented in the Monte Carlo program *** proposed method was validated using the VENUS-Ⅲ international benchmark problem and a self-shielding calculation *** results from the VENUS-Ⅲ benchmark problem showed that the grid-AIS method achieved a significant reduction in the variance of the statistical errors of the MESH grids,decreasing from 1.08×10^(-2) to 3.84×10^(-3),representing a 64.00% *** demonstrates that the grid-AIS method is effective in addressing global *** results of the selfshielding calculation demonstrate that the grid-AIS method produced accurate computational ***,the grid-AIS method exhibited a computational efficiency approximately one order of magnitude higher than that of the AIS method and approximately two orders of magnitude higher than that of the conventional Monte Carlo method.

关键词： Monte Carlo Global variance reduction Reactor shielding Automatic importance sampling

Multiple factors influencing high-purity indium electrolytic refining

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Chinese Journal of Chemical Engineering 2024年第7期71卷 148-160页

作者： Hong-Qiang Fan Fei Li Hong-Xing zheng wu-ji Pan Mei-zhen wu Yashar Behnamian Ju-Bo Peng Dong-Hai Lin State Key Laboratory of Advanced Special Steel&School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Shanghai Engineering Research Center for Integrated Circuits and Advanced Display Materials Shanghai UniversityShanghai 200444China Research&Development Center Yunnan Tin Group(Holding)Limited CompanyKunming 650032China Department of Chemical and Materials Engineering University of AlbertaEdmonton T6G 2V4AlbertaCanada School of Energy and Materials Shanghai Key Laboratory of Engineering Materials Application and EvaluationShanghai Polytechnic UniversityShanghai 201209China

The effects of various contaminants in the electrolytic refinement of indium were investigated using a glow discharge mass spectrometer(GDMS).The effects of several factors such as the indium ion(In3+)concentration,the sodium chloride(NaCl)concentration,the current density,the gelatin concentration,the pH,and the electrode distance,were *** variations in impurity levels concerning gelatin concentration were *** the gelatin and In3+concentration were moderately positively correlated with the Pb *** Sb concentration was associated positively with the NaCl concentration,while the Ti concentration had an adverse correlation with the NaCl *** Bi element content was positively linked to the electrode *** the current density increased,Cu,Pb,and Bi impurities initially rose and then eventually ***,a critical current density of 45 A·m^(-2) was identified in this behavior.

关键词： High-purity indium Electrolysis Multiple factors Electrochemistry Purification

Ruthenium-lead oxide for acidic oxygen evolution reaction in proton exchange membrane water electrolysis

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Nano Research 2024年第10期17卷 8671-8677页

作者： Feng-Yang Chen Chang Qiu zhen-Yu wu Tae-Ung Wi YZou Finfrock Haotian Wang Department of Chemical and Biomolecular Engineering Rice UniversityHoustonTX 77005USA Structural Biology Center X-ray Science DivisionArgonne National LaboratoryLemontIL 60439USA Department of Materials Science and NanoEngineering Rice UniversityHoustonTX 77005USA Department of Chemistry Rice UniversityHoustonTX 77005USA

Developing an active and stable anode catalyst for the proton exchange membrane water electrolyzer(PEM-WE)is a critical objective to enhance the economic viability of green hydrogen ***,the expensive iridium-based electrocatalyst remains the sole practical material with industrial-level stability for the acidic oxygen evolution reaction(OER)at the ***-based catalysts have been proposed as more cost-effective alternatives with improved activity,though their stability requires *** current urgent goal is to reduce costs and noble metal loading of the OER catalyst while maintaining robust activity and *** this study,we design a Ru-based OER catalyst incorporating Pb as a supporting *** electrocatalyst exhibits an OER overpotential of 201 mV at 10 mA·cm^(-2),simultaneously reducing Ru noble metal loading by~40%.Normalization of the electrochemically active surface area unveils improved intrinsic activity compared to the pristine RuO_(2) *** a practical stability test in a PEM-WE setup,our developed catalyst sustains stable performance over 300 h without notable degradation,underscoring its potential for future applications as a reliable anodic catalyst.

关键词： electrocatalysis oxygen evolution reaction water splitting proton exchange membrane water electrolyzer

Normalized glandular dose coefficients for digital breast tomosynthesis using detailed Chinese breast models

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Nuclear Science and Techniques 2024年第5期35卷 42-59页

作者： Jia-Hao Wang Rui Qiu An-Kang Hu Ye-Qi Liu zhen wu Hui Zhang Jun-Li Li Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging Ministry of EducationTsinghua UniversityBeijing 100084China Joint Institute of Tsinghua University Nuctech Company Limited BeijingBeijing 100084China

The rise in breast cancer diagnoses among Chinese women has necessitated the use of X-ray breast screening,which carries a radiation *** study aimed to provide a dosimetry protocol for the Chinese female population to replace the traditional standard that utilizes simplified breast models,for the accurate estimation of the mean glandular dose of a patient undergoing digital breast tomosynthesis(DBT).The first set of detailed Chinese female breast models and representative breast parameters was *** backscatter radiation and computational efficiency,we improved the combination of these models and the Chinese reference adult female whole-body voxel *** acquisition for four commercial DBT systems that are widely employed in China was simulated using the Monte Carlo method to obtain the normalized glandular dose coefficients of DBT(D_(gN)^(DBT))and the glandular depth dose(D_(g)^(dep)(z))for different breast characteristics and X-ray *** calculated a series of D_(gN)^(DBT) values for breasts with different percentage mass glandularities(5%,25%,50%,75%,and 100%)and compressed breast thicknesses(2,3,4,5,6,and 7 cm)at various tube potentials(25,28,30,32,35,and 49 kV)and target/filter combinations(W/Rh,W/Al,Mo/Mo,Rh/Rh,and Rh/Ag).The parameter dependence of the breast characteristics and beam conditions on D_(gN)^(DBT) in detailed breast models was *** D_(gN)^(DBT) results were 14.6-51.0%lower than those of the traditional dosimetry standard in *** difference in D_(gN)^(DBT) was mainly due to a decrease in the depth of the main energy deposition area caused by the glandular distribution along the depth *** results obtained in this study may be used to improve breast dosimetry in China and provide more detailed information on risk assessment during DBT.

关键词： Digital breast tomosynthesis Normalized glandular dose coefficients Detailed breast model Monte Carlo simulation

A zero-sum hybrid stochastic differential game with impulse controls

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Science China(Information Sciences) 2024年

作者： Siyu Lü zhen wu Jie XIONG School of Mathematics Southeast University School of Mathematics Shandong University Department of Mathematics and SUSTech International Center for Mathematics Southern University of Science and Technology

In this paper, we study a zero-sum stochastic differential game with the following salient features:(i) the system state is dictated by a hybrid diffusion,(ii) both players use impulse controls, and (iii) the game takes place on an infinite time horizon. First, the dynamic programming principle for the problem is ***, the lower and upper value functions of the game are characterized as the unique viscosity solution of the associated Hamilton-Jacobi-Bellman-Isaacs (HJBI) equation, which turns out to be a coupled system of variational inequalities with bilateral obstacles. Moreover, a verification theorem as a sufficient condition to identify a Nash equilibrium is established. The Nash equilibrium strategies for the two players, indicating when and how it is optimal to intervene, are given in terms of the obstacle part of the HJBI equation.

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A zero-sum hybrid stochastic differential game with impulse controls

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Science China(Information Sciences) 2024年第11期67卷 285-299页

作者： Siyu LV zhen wu Jie XIONG School of Mathematics Southeast University School of Mathematics Shandong University Department of Mathematics and SUSTech International Center for Mathematics Southern University of Science and Technology

In this paper, we study a zero-sum stochastic differential game with the following salient features:(i) the system state is dictated by a hybrid diffusion,(ii) both players use impulse controls, and(iii) the game takes place on an infinite time horizon. First, the dynamic programming principle for the problem is ***, the lower and upper value functions of the game are characterized as the unique viscosity solution of the associated Hamilton-Jacobi-Bellman-Isaacs(HJBI) equation, which turns out to be a coupled system of variational inequalities with bilateral obstacles. Moreover, a verification theorem as a sufficient condition to identify a Nash equilibrium is established. The Nash equilibrium strategies for the two players, indicating when and how it is optimal to intervene, are given in terms of the obstacle part of the HJBI equation.

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Heterogeneous population distribution enhances resistance to wheat lodging by optimizing the light environment

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Journal of Integrative Agriculture 2024年第7期23卷 2211-2226页

作者： Yibo Hu Feng Qin zhen wu Xiaoqin Wang Xiaolong Ren Zhikuan Jia zhenlin Wang Xiaoguang Chen Tie Cai College of Agronomy Northwest A&F UniversityYangling 712100China Key Laboratory of Crop Physi-Ecology and Tillage Science in Northwestern Loess Plateau Ministry of Agriculture and Rural AffairsNorthwest A&F UniversityYangling 712100China College of Agronomy Shandong Agricultural University/State Key Laboratory of Crop BiologyTai’an 271018China Xuzhou Institute of Agricultural Sciences in Jiangsu Xuhuai Area Xuzhou 221131China

Lodging is still the key factor that limits continuous increases in wheat yields today,because the mechanical strength of culms is reduced due to low-light stress in populations under high-yield *** mechanical properties of the culm are mainly determined by lignin,which is affected by the light ***,little is known about whether the light environment can be sufficiently improved by changing the population distribution to inhibit culm ***,in this study,we used the wheat cultivar“Xinong 979”to establish a low-density homogeneous distribution treatment(LD),high-density homogeneous distribution treatment(HD),and high-density heterogeneous distribution treatment(HD-h)to study the regulatory effects and mechanism responsible for differences in the lodging resistance of wheat culms under different population *** with LD,HD significantly reduced the light transmittance in the middle and basal layers of the canopy,the net photosynthetic rate in the middle and lower leaves of plants,the accumulation of lignin in the culm,and the breaking resistance of the culm,and thus the lodging index values increased significantly,with lodging rates of 67.5%in 2020–2021 and 59.3%in 2021–*** HD-h,the light transmittance and other indicators in the middle and basal canopy layers were significantly higher than those under HD,and the lodging index decreased to the point that no lodging *** with LD,the activities of phenylalanine ammonia-Lyase(PAL),4-coumarate:coenzyme A ligase(4CL),catechol-O-methyltransferase(COMT),and cinnamyl-alcohol dehydrogenase(CAD)in the lignin synthesis pathway were significantly reduced in the culms under HD during the critical period for culm formation,and the relative expression levels of TaPAL,Ta4CL,TaCOMT,and TaCAD were significantly ***,the activities of lignin synthesis-related enzymes and their gene expression levels were significantly increased under HD-h compare

关键词： canopy light environment lignin lodging population distribution wheat

A novel strain of Levilactobacillus brevis PDD-5 isolated from salty vegetables has beneficial effects on hyperuricemia through anti-inflammation and improvement of kidney damage

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Food Science and Human Wellness 2024年第2期13卷 898-908页

作者： Jue Xu Maolin Tu Xiankang Fan Yuxing Guo Tao Zhang Xiaoqun Zeng zhendong Cai zhen wu Daodong Pan State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products Ningbo UniversityNingbo 315211China Key Laboratory of Animal Protein Food Deep Processing Technology of Zhejiang Province College of Food and Pharmaceutical SciencesNingbo UniversityNingbo 315211China Department of Food Science and Technology School of Food Science and Pharmaceutical EngineeringNanjing Normal UniversityNanjing 210023China

Hyperuricemia is a metabolic disorder caused by abnormal purine metabolism,resulting in abnormally high serum uric *** this study,a novel Levilactobacillus brevis PDD-5 isolated from salty vegetables was verified with the function of alleviating *** relevant effects of *** PDD-5 in lowering uric acid were analyzed by in vitro and in vivo *** results showed that the *** PDD-5 has(68.86±15.46)%of inosine uptake capacity and(95.75±3.30)%of guanosine uptake capacity in *** administration of *** PDD-5 to hyperuricemia rats reduced uric acid,creatinine,and urea nitrogen in serum,as well as decreased inosine and guanosine levels in the intestinal contents of *** of relevant markers in the kidney by ELISA kits revealed that *** PDD-5 alleviated oxidative stress and ***,the gene expression of uric acid transporter 1(URAT1)and glucose transporter 9(GLUT9)was down-regulated,and the gene expression of organic anion transporter 1(OAT1)was up-regulated after treatment with *** *** blot analysis showed that *** PDD-5 alleviated hyperuricemia-induced kidney injury through the NLRP3 *** se findings suggest that *** PDD-5 can lower uric acid,repair kidney damage,and also has the potential to prevent uric acid nephropathy.

关键词： Lactic acid bacteria Purine nucleoside Hyperuricemia Uric acid nephropathy

Neuroprotective and anti-inflammatory effects of eicosane on glutamate and NMDA-induced retinal ganglion cell injury

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 638-645页

作者： zhen-Kai wu Huan-Yu Li You-Lin Zhu Meng-Qin Xiong Jing-Xiang Zhong Department of Ophthalmology the First Affiliated Hospital of Jinan UniversityGuangzhou 510632Guangdong ProvinceChina Changde Hospital Xiangya School of MedicineCentral South University(the First People’s Hospital of Changde City)Changde 415000Hunan ProvinceChina

AIM:To investigate the protective effects,antioxidant potential,and anti-inflammatory mechanisms of eicosane on glutamate-induced cell damage and on N-methyl-Daspartate(NMDA)-induced retinal ganglion cell(RGC)injury in a mouse model of ***:The protective effects of eicosane on the rat R28 retinal precursor cell line were assessed using cell counting kit-8 assays and Hoechst-propidium iodide *** reactive oxygen species(ROS)production was measured using the fluorescent probe 2'-7'-dichlorofluorescin diacetate and flow *** protective role of eicosane on NMDA-induced RGC injury in a mouse glaucoma model was determined by immunostaining of frozen sections of *** effects of eicosane on the metabolome of the retina in mice with NMDA-induced RGC damage were evaluated by liquid chromatographymass spectroscopy(LC-MS)and untargeted metabolomics ***:Eicosane treatment significantly attenuated glutamate-induced damage to R28 cells in *** also protected RGCs against NMDA-induced injury in a mouse glaucoma *** metabolomics analyses showed that eicosane increased multiple metabolites,including L-arginine and L-carnitine,in the ***:Eicosane has protective effects,antioxidant potential,and anti-inflammatory properties in an in vitro model of glutamate-induced cell damage and in an in vivo model of NMDA-induced RGC injury in mouse glaucoma through modulation of L-arginine and/or L-carnitine metabolism.

关键词： glaucoma metabolites eicosane