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Study on the optimal incident proton energy of ^(7)Li(p,n)^(7)Be neutron source for boron neutron capture therapy

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Nuclear Science and Techniques 2024年第3期35卷 170-180页

作者： yi-Nan Zhu Zuo-Kang Lin Hai-Yan Yu Ye dai Zhi-min dai Xiao-Han Yu Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Science Beijing 100049China

Boron neutron capture therapy(BNCT)is recognized as a precise binary targeted radiotherapy technique that effectively eliminates tumors through the^(10)B(n,α)^(7)Li nuclear *** various neutron sources,accelerator-based sources have emerged as particularly promising for BNCT ***^(7)Li(p,n)^(7)Be reaction is highly regarded as a potential neutron source for BNCT,owing to its low threshold energy for the reaction,significant neutron yield,appropriate average neutron energy,and additional *** study utilized Monte Carlo simulations to model the physical interactions within a lithium target subjected to proton bombardment,including neutron moderation by an MgF_(2)moderator and subsequent BNCT dose analysis using a Snyder head *** study focused on calculating the yields of epithermal neutrons for various incident proton energies,finding an optimal energy at 2.7 ***,the Snyder head phantom was employed in dose simulations to validate the effectiveness of this specific incident energy when utilizing a^(7)Li(p,n)^(7)Be neutron source for BNCT purposes.

关键词： Boron neutron capture therapy ^(7)Li(p,n)7Be neutron source Incident proton energy Monte Carlo simulation

Development and validation of novel models for the prediction of intravenous corticosteroid resistance in acute severe ulcerative colitis using logistic regression and machine learning

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Gastroenterology Report 2022年第1期10卷 498-506页

作者： Si Yu Hui Li Yue Li Hui Xu Bei Tan Bo-Wen Tian yi-min dai Feng Tian Jia-ming Qian Department of Gastroenterology Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijingP.R.China Department of Gastroenterology Shengjing Hospital of China Medical UniversityShenyangLiaoningP.R.China

Background The early prediction of intravenous corticosteroid(IVCS)resistance in acute severe ulcerative colitis(ASUC)patients remains an unresolved *** study aims to construct and validate a model that accurately predicts IVCS *** A retrospective cohort was established,with consecutive inclusion of patients who met the diagnosis criteria of ASUC and received IVCS during index hospitalization in Peking Union Medical College Hospital between March 2012 and January *** primary outcome was IVCS *** models,including logistic regression and machine learning-based models,were *** validation was conducted in an independent cohort from Shengjing Hospital of China Medical *** A total of 129 patients were included in the derivation *** index hospitalization,102(79.1%)patients responded to IVCS and 27(20.9%)failed;18(14.0%)patients underwent colectomy in 3 months;6 received cyclosporin as rescue therapy,and 2 eventually escalated to colectomy;5 succeeded with infliximab as rescue *** Ulcerative Colitis Endoscopic Index of Severity(UCEIS)and C-reactive protein(CRP)level at Day 3 are independent predictors of IVCS *** areas under the receiver-operating characteristic curves(AUROCs)of the logistic regression,decision tree,random forest,and extreme-gradient boosting models were 0.873(95%confidence interval[CI],0.704–1.000),0.648(95%CI,0.463–0.833),0.650(95%CI,0.441–0.859),and 0.604(95%CI,0.416–0.792),*** logistic regression model achieved the highest AUROC value of 0.703(95%CI,0.473–0.934)in the external *** In patients with ASUC,UCEIS and CRP levels at Day 3 of IVCS treatment appeared to allow the prompt prediction of likely IVCS *** found no evidence of better performance of machine learning-based models in IVCS resistance prediction in ASUC.A nomogrambased on the logistic regression model might aid in the management of ASUC

关键词： acute severe ulcerative colitis steroid resistance colectomy machine learning

Oxidation resistant low-alloyed Ti alloys with good ductility

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Rare Metals 2024年第8期43卷 3921-3936页

作者： Meng Li Zhang-Zhi Shi Jun-yi Xu Fu-Zhi dai Xiang-min Li Zi-Lin Li Lu-Ning Wang Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advance Metals and MaterialsSchool of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijingBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

Oxidation resistance enhancement of pure Ti often comes at the cost of reduced ductility,which is frequently the problem through alloying with sole Al,Si,W,Mo and *** overcome the short coming of single element alloying,this paper proposes a multi-element low-alloying strategy to take advantage of synergistic effects and resolve the conflict between oxidation resistance and *** demonstrates that the addition of a small quantity of Ta(0.51wt%)can boost both oxidation resistance and ductility in comparison to pure ***,the combined addition of a small amount(0.54 wt%)of Ta,Nb and Si not only preserves good ductility of pure Ti,but also reduces mass gains to 14%-67%of pure Ti during 100 h oxidation at 650-850℃in *** indicates even better oxidation resistance than that obtained through the use of Ta,Nb,or Nb+Ta *** Ta+Nb+Si alloying creates an oxide layer that is less porous and more resistant to stratification and ***,a 3-μm N-rich layer can form in the Ti substrate beneath the oxide scale,in which phase transformation generates coherent Ti_(2)N with(0001)_(Ti)as the habit plane,with N atoms prefers to diffuse along■than along[0001]_(Ti).The completely transformed Ti_(2)N region or partially transformed Ti+Ti_(2)N region can effectively impede oxygen ***,the multielement low-alloying strategy is promising for enhancing both oxidation resistance and mechanical properties of metallic materials in the future.

关键词： Ti alloys Multi-element Co-alloying Oxidation resistance Mechanical properties

Metagenomics reveals the microbial community and functional metabolism variation in the partial nitritation-anammox process:From collapse to recovery

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Journal of Environmental Sciences 2024年第1期135卷 210-221页

作者： Hong Wang Hui Gong Xiaohu dai min Yang State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China BIOMATH Department of Data Analysis and Mathematical ModellingGhent UniversityGhent 9000Belgium

Mainstream partial nitritation-anammox(PNA)process easily suffers from performance instability and even reactor collapse in ***,it is of great significance to unveil the characteristic of performance recovery,understand the intrinsic mechanism and then propose operational *** this study,we combined long-term reactor operation,batch tests,and metagenomics to reveal the succession of microbial community and functional metabolism variation from system collapse to *** aeration control(0.10-0.25mg O_(2)/L)was critical for performance *** was also found that Candidatus Brocadia became the dominant flora and its abundance increased from 3.5%to 11.0%.Significant enhancements in carbon metabolism and phospholipid biosynthesis were observed during system recovery,and the genes abundance related to signal transduction was dramatically *** up-regulation of sdh and suc genes showed the processes of succinate dehydrogenation and succinyl-CoA synthesis might stimulate the production of amino acids and the synthesis of proteins,thereby possibly improving the activity and abundance of AnAOB,which was conducive to the performance ***,the increase in abundance of hzs and hdh genes suggested the enhancement of the anammox *** in the abundance of key genes involved in nitrogen metabolism indicated that nitrogen removal pathway was more diverse after system *** achievement of performance recovery was driven by anammox,nitrification and denitrification coupled with dissimilatory nitrate reduction to *** results provide deeper insights into the recovery mechanism of PNA system and also provide a potential regulation strategy for the stable operation of the mainstream PNA process.

关键词： Partial nitritation-anammox Metagenomics Microbial community Functional metabolism Recovery

Phase-Field Simulation of Sintering Process:A Review

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1165-1204页

作者： ming Xue min yi State Key Laboratory ofMechanics and Control forAerospace Structures&Institute for Frontier Science&Key Laboratory for Intelligent Nano Materials and Devices of ministry of Education&College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics(NUAA)Nanjing210016China

Sintering,a well-established technique in powder metallurgy,plays a critical role in the processing of high melting point materials.A comprehensive understanding of structural changes during the sintering process is essential for effective product *** phase-field method stands out for its unique ability to simulate these structural *** its widespread application,there is a notable absence of literature reviews focused on its usage in sintering ***,this paper addresses this gap by reviewing the latest advancements in phase-field sintering models,covering approaches based on energy,grand potential,and entropy *** characteristics of various models are extensively discussed,with a specific emphasis on energy-based models incorporating considerations such as interface energy anisotropy,tensor-form diffusion mechanisms,and various forms of rigid particle motion during ***,the paper offers a concise summary of phase-field sintering models that integrate with other physical fields,including stress/strain fields,viscous flow,temperature field,and external electric *** conclusion,the paper provides a succinct overview of the entire content and delineates potential avenues for future research.

关键词： Phase-field model review sintering additive manufacturing

Mitigating methane emissions:Domestic and joint efforts by the United States and China

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Environmental Science and Ecotechnology 2024年第4期20卷 2-5页

作者： Fan dai yi Wang California-China Climate Institute The University of CaliforniaBerkeleyUSA Institutes of Science and Development Chinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina

During the Glasgow climate conference,the United States(U.S.)and China jointly committed to reduce methane emissions as a prioritized area of their bilateral cooperation in addressing climate change in the *** methane's strongwarming effect,which is over 80 times more potent than carbon dioxide in the first 20 years after release,reducing methane emissions is crucial to slowing down climate change in the near future[1].1 The significance of this joint commitment was reiterated in the recent U.S.-China Sunnylands Statement on Climate Cooperation,emphasizing the urgency and importance of reducing methane emissions both within each country's borders and through collaborative efforts.

关键词： methane dioxide iterated

Design of Protograph LDPC-Coded MIMO-VLC Systems with Generalized Spatial Modulation

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China Communications 2024年第3期21卷 118-136页

作者： dai Lin Fang yi Guan Yongliang Mohsen Guizani School of Information Engineering Guangdong University of TechnologyGuangzhou 51006China The State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an 710126China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore Department of Machine Learning Mohamed Bin Zayed University of Artificial Intelligence(MBZUAI)Abu DhabiUnited Arab Emirates

This paper investigates the bit-interleaved coded generalized spatial modulation(BICGSM) with iterative decoding(BICGSM-ID) for multiple-input multiple-output(MIMO) visible light communications(VLC). In the BICGSM-ID scheme, the information bits conveyed by the signal-domain(SiD) symbols and the spatial-domain(SpD) light emitting diode(LED)-index patterns are coded by a protograph low-density parity-check(P-LDPC) code. Specifically, we propose a signal-domain symbol expanding and re-allocating(SSER) method for constructing a type of novel generalized spatial modulation(GSM) constellations, referred to as SSERGSM constellations, so as to boost the performance of the BICGSM-ID MIMO-VLC ***, by applying a modified PEXIT(MPEXIT) algorithm, we further design a family of rate-compatible P-LDPC codes, referred to as enhanced accumulate-repeat-accumulate(EARA) codes,which possess both excellent decoding thresholds and linear-minimum-distance-growth property. Both analysis and simulation results illustrate that the proposed SSERGSM constellations and P-LDPC codes can remarkably improve the convergence and decoding performance of MIMO-VLC systems. Therefore, the proposed P-LDPC-coded SSERGSM-mapped BICGSMID configuration is envisioned as a promising transmission solution to satisfy the high-throughput requirement of MIMO-VLC applications.

关键词： bit-interleaved coded modulation generalized spatial modulation multiple-input multipleoutput protograph LDPC codes visible light communication

Prenatal amoxicillin exposure induces developmental toxicity in fetal mice and its characteristics

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Journal of Environmental Sciences 2024年第3期137卷 287-301页

作者： Yongguo dai Yu Peng Wen Hu yi Liu Hui Wang Department of Pharmacology Wuhan University School of Basic Medical SciencesWuhan 430071China Department of Pharmacy Zhongnan Hospital of Wuhan UniversityWuhan 430071China Hubei Provincial Key Laboratory of Developmentally Originated Disease Wuhan 430071China

Amoxicillin,a widely used antibiotic in human and veterinary pharmaceuticals,is now considered as an“emerging contaminant”because it exists widespreadly in the environment and brings a series of adverse ***,systematic studies about the developmental toxicity of amoxicillin are still *** explored the potential effects of amoxicillin exposure on pregnancy outcomes,maternal/fetal serum phenotypes,and fetal multiple organ development in mice,at different doses(75,150,300 mg/(kg·day))during late-pregnancy,or at a dose of 300 mg/(kg·day)during different stages(mid-/latepregnancy)and courses(single-/multi-course).Results showed that prenatal amoxicillin exposure(PAmE)had no significant infuence on the body weights of dams,but it could inhibit the physical development and reduce the survival rate of fetuses,especially during the ***,PAmE altered multiple maternal/fetal serum phenotypes,especially in *** multi-organ function results showed that PAmE inhibited testicular/adrenal steroid synthesis,long bone/cartilage and hippocampal development,and enhanced ovarian steroid synthesis and hepatic glycogenesis/lipogenesis,and the order of severity might be gonad(testis,ovary)>liver>*** analysis found that PAmE-induced multiorgan developmental and functional alterations had differences in stages,courses and fetal gender,and the most obvious changes might be in high-dose,late-pregnancy and multicourse,but there was no typical rule of a dose-response *** conclusion,this study confirmed that PAmE could cause abnormal development and multi-organ function alterations,which deepens our understanding of the risk of PAmE and provides an experimental basis for further exploration of the long-term harm.

关键词： Amoxicillin Prenatal exposure Fetal development Organ function Developmental toxicity

Churning loss characteristics of a wet three-phase high-speed reluctance motor

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第3期25卷 251-267页

作者： Zhenzhou ZHANG mingzhu dai Chenchen ZHANG yi CHEN Bin MENG College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023China

With the increasing requirements of electro-hydrostatic actuators(EHAs)for power,volume,and pressure,there is a growing tendency in the industry to combine the motor and pump to form a so-called'motor pump'to improve the *** this paper,a novel structure for a wet three-phase high-speed reluctance motor pump is proposed,which can further improve integration by removing the dynamic seal on the pump shaft,thereby avoiding the problems of dynamic seal wear and oil leakage and improving heat dissipation under high-speed working ***,after the motor is wetted,the churning loss caused by immersion of the rotor in the oil causes additional fluid resistance *** on fundamental fluid mechanics,an analytical model of the churning torque of a wet motor was *** verify the accuracy of the analytical model,a simulation model of churning loss was established based on computational fluid dynamics(CFD),and the churning torque and flow field state were ***,an experimental prototype was designed and manufactured,and a test bench for churning loss was *** oil churning torque was measured at different speeds and *** results from the analytical,simulation,and experimental models agreed *** experimental results validated the analytical model and CFD *** research provides a practical method for calculating the churning loss and serves as guidance for future optimization of churning loss reduction.

关键词： Motor pump Wet motor Churning loss Analytical model Computational fluid dynamics(CFD)