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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 calculations.The global variance reduction problem requires that the statistical error of the entire space is uniform.This 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 MCShield.The proposed method was validated using the VENUS-Ⅲ international benchmark problem and a self-shielding calculation example.The 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% reduction.This demonstrates that the grid-AIS method is effective in addressing global issues.The results of the selfshielding calculation demonstrate that the grid-AIS method produced accurate computational results.Moreover,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

Wood use and forest management by Neolithic millet farmers at the Xinglong site,northern China

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Science China Earth Sciences 2024年第6期67卷 1910-1921页

作者： hui shen Zhenwei QIU Keliang ZHAO Xinying ZHOU Xiaoqiang LI Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China National Museum of China Beijing 100006China University of Chinese Academy of Sciences Beijing 100049China

The origin and development of agriculture and its relationship with climate change are hotly debated topics among environmental archaeologists.In this study,we analyzed wood charcoal materials from the Neolithic Xinglong site in northern China in order to understand the woody vegetation around the site and how early millet farmers shaped local woodlands.Our results suggest that the area around the Xinglong sites during 8700-7000 yr BP was primarily woodlands,including Prunus sibirica shrubs,Ulmus and Acer forests,and Populus stands near waterways.From 8000 to 7000 yr BP,the warm and humid climate probably contributed to the expansion of Acer,Rhamnus,and Juniperus,and may have facilitated the development of early millet agriculture.Among these ancient wood fragments that we studied,the high percent of Prunus charcoal appears to indicate an abundance of fruit trees,which might have constituted the main component of local vegetation.Meanwhile,the wood taxa illustrate the existence of a variety of ecological habitats,and it is logical to assume that people made full use of the locally available wood resources.Notably,Populus and Ulmus were the dominant sources of fuel.The results of tree-ring curvature analyses indicate that people mainly collected trunks or large branches of Ulmus,Populus,Acer,and Juniperus timbers.We interpret the increasing use of Prunus twigs and the declining percentage of Prunus charcoal in the period between 8000-7000 yr BP as indicating that people started to protect and manage wild fruit trees.They may have started pruning to acquire more food resources as part of the cultural responses and adaptation strategies employed by these early millet cultivators.

关键词： Xinglong site Wood charcoal Wood use Woodland management

Potential risks of organic contaminated soil after persulfate remediation:Harmful gaseous sulfur release

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Journal of Environmental Sciences 2024年第1期135卷 1-9页

作者： Yuyang Long Zixiao Wu Xiaodong Ding Jiansong Chen Dongsheng shen Jiali shentu Cai hui Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling Zhejiang Engineering Research Center of Non-ferrous Metal Waste RecyclingInstrumental Analysis CenterSchool of Environmental Science and EngineeringZhejiang Gongshang UniversityHangzhou 310012China Shangyu Yingtai Fine Chemical Co. Ltd.Shaoxing 312000China Hangzhou Ecological Environment Monitoring Center Hangzhou 310007China

Persulfate is considered a convenient and efficient remediation agent for organic contaminated soil.However,the potential risk of sulfur into the soil remediation by persulfate remains ignored.In this study,glass bottles with different persulfate dosages and groundwater tables were set up to simulate persulfate remediation of organic pollutants(aniline).The results found sulfate to be the main end-product(83.0%–99.5%)of persulfate remediation after10 days.Moreover,H_(2)S accounted for 93.4%–99.4%of sulfur reduction end-products,suggesting that H_(2)S was the final fate of sulfur.H_(2)S was released rapidly after one to three days at a maximum concentration of 33.0 ppm,which is sufficient to make a person uncomfortable.According to the fitted curve results,H_(2)S concentration decreased to a safe concentration(0.15 ppm)after 20–85 days.Meanwhile,the maximum concentration of methanethiol reached 0.6 ppm.These results indicated that secondary pollution from persulfate remediation could release harmful gases over a long time.Therefore,persulfate should be used more carefully as a remediation agent for soil contamination.

关键词： Gaseous sulfur release H_2S Long period potential risk Organic contaminated soil remediation Persulfate

Injectable chitosan hydrogels loaded with antioxidant agent as first-aid dressings for second-degree burn wounds

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Science China(Technological Sciences) 2024年第3期67卷 891-901页

作者： REN hui ZHANG Zhen LU KaiLun shen YuanYuan HE ChaoLiang CHEN XueSi CAS Key Laboratoryof Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Burn wounds are destructive skin traumas typically of irregular shape and large area. Prone to infection, they require frequent dressing replacement, and painless removal of dressings from burn wounds remains a major challenge. This study focuses on the dynamic characteristics and treatment difficulty of burn wounds. Hydrogel dressings based on glycol chitosan and propionaldehyde-or benzaldehyde-terminated 4-arm poly(ethylene glycol) were designed on the basis of Schiff base cross-linking networks. The hydrogels exhibited shape-adaptability, self-healing and fast-degradation properties, which makes these hydrogels suitable for burn wounds. Salvianolic acid B(SaB)-loaded hydrogel exhibited good antioxidant properties in vitro. In a rat model of deep second-degree burn wounds, the SaB-loaded hydrogel could quickly reduce wound temperature, regulate wound oxidant microenvironment, promote angiogenesis, and accelerate wound healing. Thus, the drug-loaded hydrogel shows significant potential as a first-aid dressing for treatment of burn wounds.

关键词： hydrogel dressing fast-degradation shape-adaptability stress relaxation burn wound treatment

Vibration Suppression for Active Magnetic Bearings Using Adaptive Filter with Iterative Search Algorithm

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 61-71页

作者： Jin-hui Ye Dan Shi Yue-sheng Qi Jin-hui Gao Jian-Xin shen IEEE Department of Electrical Engineering Zhejiang UniversityHangzhou 310027China CES and IEEE

Active Magnetic Bearing(AMB) is a kind of electromagnetic support that makes the rotor movement frictionless and can suppress rotor vibration by controlling the magnetic force. The most common approach to restrain the rotor vibration in AMBs is to adopt a notch filter or adaptive filter in the AMB controller. However, these methods cannot obtain the precise amplitude and phase of the compensation current. Thus, they are not so effective in terms of suppressing the vibrations of the fundamental and other harmonic orders over the whole speed range. To improve the vibration suppression performance of AMBs,an adaptive filter based on Least Mean Square(LMS) is applied to extract the vibration signals from the rotor displacement signal. An Iterative Search Algorithm(ISA) is proposed in this paper to obtain the corresponding relationship between the compensation current and vibration signals. The ISA is responsible for searching the compensating amplitude and shifting phase online for the LMS filter, enabling the AMB controller to generate the corresponding compensation force for vibration suppression. The results of ISA are recorded to suppress vibration using the Look-Up Table(LUT) in variable speed range. Comprehensive simulations and experimental validations are carried out in fixed and variable speed range, and the results demonstrate that by employing the ISA, vibrations of the fundamental and other harmonic orders are suppressed effectively.

关键词： Active Magnetic Bearing(AMB) Adaptive filter Iterative search algorithm Least mean square(LMS) Vibration suppression

Acupuncture and moxibustion for irritable bowel syndrome:An umbrella systematic review

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Journal of Integrative Medicine 2024年第1期22卷 22-31页

作者： Yue-ying Ma Zhou Hao Zi-yi Chen Yan-xi shen hui-rong Liu Huan-gan Wu Chun-hui Bao Shanghai Clinical Research Centre for Acupuncture and Moxibustion Yueyang Hospital of Integrated Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghai 200437China Key Laboratory of Acupuncture and Immunological Effects Shanghai University of Traditional Chinese MedicineShanghai 200030China

BackgroundIrritable bowel syndrome(IBS)is a functional bowel disease characterized by abdominal pain or discomfort associated with altered bowel habits.Several clinical studies have demonstrated the effectiveness of acupuncture and moxibustion for IBS.Many systematic reviews of acupuncture and moxibustion for IBS have been published in recent years,but their results are not entirely consistent.ObjectiveTo evaluate the methodological,reporting,and evidence quality of systematic reviews of acupuncture and moxibustion for IBS.Search strategySystematic reviews of acupuncture and moxibustion for IBS published before February 20,2023 were searched in eight databases:PubMed,Embase,Cochrane Library,Web of Science,China National Knowledge Infrastructure,Wanfang Data,VIP Database for Chinese Technical Periodicals,and China Biology Medicine.The keywords used for literature search were acupuncture,moxibustion,systematic review,meta-analysis,and irritable bowel syndrome.Inclusion criteriaSystematic reviews and meta-analyses of randomized controlled trials of acupuncture and moxibustion for IBS were included.Data extraction and analysisRelevant information was independently extracted by two investigators.The A MeaSurement Tool to Assess systematic Reviews 2(AMSTAR 2),Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA 2020),and Grading of Recommendations Assessment,Development and Evaluation(GRADE)were used to evaluate the methodological quality,reporting quality and evidence quality,respectively.ResultsA total of 342 studies were retrieved and 15 systematic reviews were included.The results of AMSTAR 2 showed low methodological quality in 2 studies and very low methodological quality in the remaining 13 studies,with main issues being failure to register a protocol,incomplete search strategy,not providing a list of excluded studies,incomplete consideration of the risk of bias in the included studies,and a failure to assess the publication bias.The results of PRISMA 2020 showed seriously deficient reportin

关键词： Irritable bowel syndrome Acupuncture Moxibustion Umbrella systematic review Systematic review

Impact of different anastomosis methods on post-recurrence after intestinal resection for Crohn's disease:A meta-analysis

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World Journal of Gastrointestinal Surgery 2024年第4期16卷 1165-1175页

作者： Zheng-Zuo Wang Chun-Hua Zhao hui shen Gui-Ping Dai Department of Anorectal Jiashan Hospital of Traditional Chinese MedicineJiaxing 314100Zhejiang ProvinceChina Department of Oncology Jiashan Hospital of Traditional Chinese MedicineJiaxing 314100Zhejiang ProvinceChina Department of Gastroenterology Jiashan Hospital of Traditional Chinese MedicineJiaxing 314100Zhejiang ProvinceChina Department of Oncology The Second Hospital of JiaxingJiaxing 314000Zhejiang ProvinceChina

BACKGROUND Crohn's disease(CD)is a chronic inflammatory disease of the gastrointestinal tract,often requiring intestinal resection as a common treatment.However,recurrence after surgery is common.The anastomotic configuration after bowel resection appears to be associated with the recurrence of CD.Previous studies have suggested that the Kono-S anastomosis may help to reduce the recurrence rate.However,the results remain controversial.Therefore,evidence-based evidence is needed to prove the advantages of Kono-S anastomosis.AIM To measure the influence of anastomosis techniques on the long-term relapse rate of CD by conducting a meta-analysis.METHODS PubMed,Scopus,and Cochrane Library were searched until October 8,2023.Patients who underwent intestinal resection due to CD were included.The intervention measures included Kono-S anastomosis,whereas the control group received traditional anastomosis such as end-to-end,end-to-side,and side-to-side anastomosis.Only randomized clinical trials and observational studies were included.The primary outcome measures were hospital stay post-surgery,overall postoperative complication incidence,the proportion of Clavien-Dindo grade IIIa or higher,overall postoperative recurrence rate,and Rutgeerts score.RESULTS From 2011 to 2023,six articles met the inclusion and exclusion criteria.The results indicated that Kono-S anastomosis can reduce the hospital stay post-surgery of patients with CD[MD=-0.26,95%CI:-0.42 to-0.10,P=0.002]than other traditional anastomosis methods.Compared to other traditional anastomosis methods,Kono-S anastomosis can significantly reduce the total recurrence rate[MD=0.40,95%CI:0.17 to 0.98,P=0.05]and postoperative Rutgeerts score[MD=-0.81,95%CI:-0.96 to-0.66,P<0.001]in patients with CD.However,there is no significant disparity in the overall occurrence of postoperative complications and the proportion of Clavien-Dindo≥IIIa.CONCLUSION Kono-S anastomosis has the potential to expedite the recuperation of CD and diminish relapse hazards;however,additional larger

关键词： Kono-S Crohn’s disease Traditional anastomosis Postoperative recurrence Meta-analysis

Mpox(formerly monkeypox):pathogenesis,prevention,and treatment

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Signal Transduction and Targeted Therapy 2024年第1期9卷 234-248页

作者： Junjie Lu hui Xing Chunhua Wang Mengjun Tang Changcheng Wu Fan Ye Lijuan Yin Yang Yang Wenjie Tan Liang shen Xiangyang Central Hospital Affiliated Hospital of Hubei University of Arts and ScienceHubei ProvinceXiangyang 441021China NHC Key Laboratory of Biosafety National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China College of Biotechnology Tianjin University of Science&TechnologyTianjin 300457China shenzhen Key Laboratory of Pathogen and Immunity National Clinical Research Center for infectious diseaseState Key Discipline of Infectious DiseaseShenzhen Third People’s HospitalSecond Hospital Affiliated to Southern University of Science and TechnologyShenzhen 518112China

In 2022,a global outbreak of Mpox(formerly monkeypox)occurred in various countries across Europe and America and rapidly spread to more than 100 countries and regions.The World Health Organization declared the outbreak to be a public health emergency of international concern due to the rapid spread of the Mpox virus.Consequently,nations intensified their efforts to explore treatment strategies aimed at combating the infection and its dissemination.Nevertheless,the available therapeutic options for Mpox virus infection remain limited.So far,only a few numbers of antiviral compounds have been approved by regulatory authorities.Given the high mutability of the Mpox virus,certain mutant strains have shown resistance to existing pharmaceutical interventions.This highlights the urgent need to develop novel antiviral drugs that can combat both drug resistance and the potential threat of bioterrorism.Currently,there is a lack of comprehensive literature on the pathophysiology and treatment of Mpox.To address this issue,we conducted a review covering the physiological and pathological processes of Mpox infection,summarizing the latest progress of anti-Mpox drugs.Our analysis encompasses approved drugs currently employed in clinical settings,as well as newly identified small-molecule compounds and antibody drugs displaying potential antiviral efficacy against Mpox.Furthermore,we have gained valuable insights from the process of Mpox drug development,including strategies for repurposing drugs,the discovery of drug targets driven by artificial intelligence,and preclinical drug development.The purpose of this review is to provide readers with a comprehensive overview of the current knowledge on Mpox.

关键词： prevention treatment intensified

Enhancing thermodynamic stability of single-crystal Ni-rich cathode material via a synergistic dual-substitution strategy

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Journal of Energy Chemistry 2024年第1期88卷 428-436,I0010页

作者： Jixue shen hui Li Haoyu Qi Zhan Lin Zeheng Li Chuanbo Zheng Weitong Du Hao Chen Shanqing Zhang School of Metallurgy Engineering Jiangsu University of Science and TechnologyZhangjiagang 215600JiangsuChina School of Metallurgy and Environment Central South UniversityChangsha 410083HunanChina Guangdong Laboratory of Chemistry and Fine Chemical Industry Jieyang Center Jieyang 515200GuangdongChina Institute of Sustainable Transformation School of Chemical Engineering and Light IndustryGuangdong University of TechnologyGuangzhou 510006GuangdongChina Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027ZhejiangChina Centre for Catalysis and Clean Energy School of Environment and ScienceGold Coast CampusGriffith UniversityGold Coast 4222QueenslandAustralia

Nickel(Ni)-rich cathode materials have become promising candidates for the next-generation electrical vehicles due to their high specific capacity.However,the poor thermodynamic stability(including cyclic performance and safety performance or thermal stability)will restrain their wide commercial application.Herein,a single-crystal Ni-rich Li Ni_(0.83)Co_(0.12)Mn_(0.05)O_(2) cathode material is synthesized and modified by a dual-substitution strategy in which the high-valence doping element improves the structural stability by forming strong metal–oxygen binding forces,while the low-valence doping element eliminates high Li^(+)/Ni^(2+)mixing.As a result,this synergistic dual substitution can effectively suppress H2-H3 phase transition and generation of microcracks,thereby ultimately improving the thermodynamic stability of Ni-rich cathode material.Notably,the dual-doped Ni-rich cathode delivers an extremely high capacity retention of 81%after 250 cycles(vs.Li/Li+)in coin-type half cells and 87%after 1000 cycles(vs.graphite/Li^(+))in pouch-type full cells at a high temperature of 55℃.More impressively,the dual-doped sample exhibits excellent thermal stability,which demonstrates a higher thermal runaway temperature and a lower calorific value.The synergetic effects of this dual-substitution strategy pave a new pathway for addressing the critical challenges of Ni-rich cathode at high temperatures,which will significantly advance the high-energy-density and high-safety cathodes to the subsequent commercialization.

关键词： Ni-rich cathode Single crystalline Dual-substitution strategy High-temperature cathode Li-ion batteries