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Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and techniques 2024年第3期35卷 208-215页

作者： Zhi-Lin Shen Jian-Jun he Key Laboratory of Beam technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)he,^(4)he,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAt was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)he,d(d,p)t,d(p,γ)^(3)he,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) he *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

the Minimum Centroid Branch Spanning tree Problem

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Journal of the Operations Research Society of China 2024年第2期12卷 528-539页

作者： Hao Lin Cheng he School of Science Henan University of TechnologyZhengzhou450001HenanChina

For a spanning tree t of graph G,the centroid of t is a vertex v for which the largest component of t-v has as few vertices as *** number of vertices of this component is called the centroid branch weight of *** minimum centroid branch spanning tree problem is to find a spanning tree t of G such that the centroid branch weight is *** application to design of communication networks,the loads of all branches leading from the switch center should be as balanced as *** this paper,we prove that the problem is strongly NP-hard even for bipartite ***,the problem is shown to be polynomially solvable for split graphs,and exact formulae for special graph familis,say Kn_(1),n_(2),...,n_(k)and P_(m)×P_(n),are presented.

关键词： Spanning tree optimization Centroid branch-NP-hardness Polynomial-time algorithm

Virtually coupled train set control subject to space-time separation: A distributed economic MPC approach with emergency braking configuration

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High-speed Railway 2024年第3期2卷 143-152页

作者： Luo x. tang t. Wang L. Liu H. State Key Laboratory of Advanced Rail Autonomous Operation Beijing Jiaotong University Beijing 100044 China Department of Electrical and Computer Engineering University of California Riverside 92521 CA United States Beijing Zongheng Electro-Mechanical technology Development Co. Ltd. Beijing 100081 China School of Automation and Intelligence Beijing Jiaotong University Beijing 100044 China National Engineering Research Center of Rail transportation Operation and Control System Beijing Jiaotong University Beijing 100044 China

the emerging virtual coupling technology aims to operate multiple train units in a Virtually Coupled train Set (VCtS) at a minimal but safe distance. to guarantee collision avoidance, the safety distance should be calculated using the state-of-the-art space-time separation principle that separates the Emergency Braking (EB) trajectories of two successive units during the whole EB process. In this case, the minimal safety distance is usually numerically calculated without an analytic formulation. thus, the constrained VCtS control problem is hard to address with space-time separation, which is still a gap in the existing literature. to solve this problem, we propose a Distributed Economic Model Predictive Control (DEMPC) approach with computation efficiency and theoretical guarantee. Specifically, to alleviate the computation burden, we transform implicit safety constraints into explicitly linear ones, such that the optimal control problem in DEMPC is a quadratic programming problem that can be solved efficiently. For theoretical analysis, sufficient conditions are derived to guarantee the recursive feasibility and stability of DEMPC, employing compatibility constraints, tube techniques and terminal ingredient tuning. Moreover, we extend our approach with globally optimal and distributed online EB configuration methods to shorten the minimal distance among VCtS. Finally, experimental results demonstrate the performance and advantages of the proposed approaches. © 2024 Beijing Jiaotong University

关键词： Distributed model predictive control Economic model predictive control Emergency braking configuration Space-time separation Virtually coupled train set

D-type neuropeptide decorated AIEgen/RENP hybrid nanoprobes with light-driven ROS generation ability for NIR-Ⅱ fluorescence imaging-guided through-skull photodynamic therapy of gliomas

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Aggregate 2024年第1期5卷 185-195页

作者： xuelu he Yuan Luo Yanying Li Yuanbo Pan Ryan t.K.Kwok Lulu he xiaolin Duan Pengfei Zhang Aiguo Wu Ben Zhong tang Juan Li Ningbo Key Laboratory of Biomedical Imaging Probe Materials and technology Zhejiang International Cooperation Base of Biomedical Materials Technology and ApplicationChinese Academy of Sciences(CAS)Key Laboratory of Magnetic Materials and DevicesNingbo Cixi Institute of Biomedical EngineeringZhejiang Engineering Research Center for Biomedical MaterialsNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingboP.R.China Guangdong Key Laboratory of Nanomedicine Shenzhen Engineering Laboratory of Nanomedicine and NanoformulationsCAS-HK Joint Lab for BiomaterialsResearch Laboratory for Biomedical Optics and Molecular ImagingShenzhen Key Laboratory for Molecular ImagingCAS Key Lab for Health InformaticsShenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhenP.R.China Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction and Institute for Advanced StudyThe Hong Kong University of Science and Technology(HKUST)KowloonP.R.China School of Science and Engineering Shenzhen Institute of Aggregate Science and TechnologyThe Chinese University of Hong KongShenzhenP.R.China

Glioma is one of the most common malignant tumors of the central nervous system,leading high mortality rates in ***-induced emission(AIE)photosensitizers-based photodynamic therapy(PDt)has emerged as a promising therapeutic strategy for least-invasive treatment of glioma,which involves local irradiation of the tumor using an external near-infrared(NIR)***,most AIE photosensitizers suffered from poorly penetration of the visible light excitation,bad spatiotemporal resolution in deep tissues and low efficient blood-brain barrier(BBB)crossing ability,which greatly limited the clinical practice of AIE photosensitizers for especially deep-seated brain tumor *** this work,we developed a multifunctional NIR-driven theranostic agent through hybrid of AIE photosensitizers tIND with rare-earth doping nanoparticles(RENPs)NaGdF4:Nd/Yb/tm with up/down dual-mode conversion *** theranostic agent was further decorated with D-type neuropeptide DNPY for crossing BBB and targeting *** the 808-nm light irradiation,the down-conversion NIR-II luminescence could indicate the position glioma and the upconversion NIR-I luminescence could trigger the AIE photosensitizers producing reactive oxygen species to inhibit orthotopic glioma tumor growth in *** results demonstrate that the integration of Dtype neuropeptide,AIE photosensitizers and RENPs could be promising candidates for in vivo NIR-II fluorescence image-guided through-skull PDt treatments of brain tumors.

关键词： aggregation-induced emission D-type neuropeptide glioma photodynamic therapy rare-earth doping nanoparticles

Leptin Modulates the Differentiation of Keratinocytes via Autophagy in Psoriasis Patients with Metabolic Syndrome

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International Journal of Dermatology and Venereology 2024年第3期7卷 121-130页

作者： Song C.-H. Wang R. Zhao Z.-K. Zhang Y. Sun J. Zhang x. Ding x.-Y. Bai J. Liang x.-Q. Wei x.-J. Liu x.-L. Yang t. Liang x.-L. Li C.-x. Lin B.-W. Department of Dermatology PLA General Hospital Beijing 100853 China Department of Clinical Laboratory PLA General Hospital Beijing 100853 China Department of Dermatology Southern Medical University Guangdong Guangzhou 510515 China

Objective: Psoriasis is associated with a high prevalence of metabolic syndrome (MS), and patients with concomitant psoriasis and MS are more severely affected and less responsive to treatment. However, the molecular mechanisms behind these effects are unknown. Recent studies have shown that leptin may serve as a molecular link between psoriasis and MS, suggesting that high leptin concentrations may exacerbate psoriasis. However, the molecular mechanism of this effect is still unclear. We aimed to investigate the effect of leptin on autophagy in patients with psoriasis. Methods: From January 2021 to June 2022 in PLA General Hospital, we enrolled 51 patients with psoriasis, including 21 patients with MS and 30 without MS, and 30 healthy controls who had undergone nevus surgery. We measured the epidermal leptin, P62, and LC3B concentrations of patients by immunohistochemistry, and measured the serum leptin concentration by enzyme-linked immunosorbent assay. We then performed correlation analyses to compare these proteins' concentrations between patients with concomitant psoriasis and MS, patients with psoriasis alone, and healthy control groups. Additionally, we performed western blotting after in vitro culture of HaCat cells with different concentrations of leptin and measured the expression levels of the autophagy markers Beclin1, LC3B, and P62; the differentiation markers K10, K16, and K17; and PI3K/AKt/mtOR signaling pathway-related proteins of HaCat cells. Next, we transfected AtG5 into HaCat cells to revert autophagy and used the specific PI3K inhibitor LY294002 to block PI3K/AKt/mtOR signaling. the expression levels of K10, K16, and K17 of HaCat cells were again measured. One-way analysis of variance was used for the comparison of means of multiple samples, and LSD-t post hoc test was used for comparison between the 2 groups. the counting data were analyzed by the chi-square test. Correlations were evaluated by Pearson correlation analysis. Results: the serum l

关键词： autophagy keratinocyte differentiation leptin metabolic syndrome PI3K/AKt/mtOR psoriasis signal pathway

the Role of Adipose tissue-derived Exosomes in Chronic Metabolic Disorders

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Current Medical Science 2024年第3期44卷 463-474页

作者： Rui he Yong CheN Division of Endocrinology Department of Internal MedicineTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Laboratory of Endocrinology & Metabolism Key Laboratory of Vascular Aging of the Ministry of EducationTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Branch of National Clinical Research Center for Metabolic Diseases Wuhan430030China

Excessive fat deposition in obese subjects promotes the occurrence of metabolic diseases,such as type 2 diabetes mellitus(t2DM),cardiovascular diseases,and non-alcoholic fatty liver disease(NAFLD).Adipose tissue is not only the main form of energy storage but also an endocrine organ that not only secretes adipocytokines but also releases many extracellular vesicles(EVs)that play a role in the regulation of whole-body *** are a subtype of EVs,and accumulating evidence indicates that adipose tissue exosomes(At Exos)mediate crosstalk between adipose tissue and multiple organs by being transferred to targeted cells or tissues through paracrine or endocrine ***,the roles of At Exos in crosstalk with metabolic organs remain to be fully *** this review,we summarize the latest research progress on the role of At Exos in the regulation of metabolic ***,we discuss the potential role of At Exos as biomarkers in metabolic diseases and their clinical application.

关键词： exosome adipose tissue obesity diabetes chronic metabolic disorder miRNA

Experimental study on reactions between alkaline basaltic melt and orthopyroxenes: constraints on the evolution of lithospheric mantle in the North China Craton

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Acta Geochimica 2024年第2期43卷 354-365页

作者： Hanqi he Mingliang Wang Hongfeng tang Key Laboratory for High temperature and High Pressure Study of the Earth’s Interior Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China School of Resource and Civil Engineering Suzhou UniversitySuzhou 234000AnhuiChina

the experimental results of the reactions between an alkaline basaltic melt and mantle orthopyroxenes under high-temperature and high-pressure conditions of 1300–1400℃ and 2.0–3.0 GPa using a six-anvil apparatus are reported in this *** reactions are proposed to simulate the interactions between melts from the asthenospheric mantle and the lithospheric *** starting melt in the experiments was made from the alkaline basalt occurring in Fuxin,Liaoning Province,and the orthopyroxenes were separated from the mantle xenoliths in Damaping,hebei *** results show that clinopyroxenes were formed in all the reactions between the alkaline basaltic melt and orthopyroxenes under the studied P–t *** formation of clinopyroxene in the reaction zone is mainly controlled by dissolution–crystallization,and the chemical compositions of the reacted melt are primarily infl uenced by the diff usion eff *** is the most important parameter controlling the reactions between the melt and orthopyroxenes,which has a direct impact on the melting of orthopyroxenes and the diff usion of chemical components in the *** also directly controls the chemical compositions of the newly formed clinopyroxenes in the reaction zone and the reacted *** formation of clinopyroxenes from the reactions between the alkaline basaltic melt and orthopyroxenes can result in an increase of CaO and Al_(2)O_(3) contents in the rocks containing this ***,the reactions between the alkaline basaltic melt from the asthenospheric mantle and orthopyroxenes from the lithospheric mantle can lead to the evolution of lithospheric mantle in the North China Craton from refractory to fertile with relatively high CaO and Al 2 O 3 *** addition,the reacted melts in some runs were transformed from the starting alkaline basaltic into tholeiitic after reactions,indicating that tholeiitic magma could be generated from alkaline basaltic one via reactions betwe

关键词： Alkaline basaltic melt Orthopyroxene Melt–mineral reaction High-temperature and high-pressure experiment Genesis of basalt Evolution of lithospheric mantle in the North China Craton

Large non-pedunculated colorectal polyp management: the elephant in the room

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World Journal of Gastroenterology 2024年第25期30卷 3126-3131页

作者： Shirley x Jiang Neal Shahidi Department of Medicine University of British ColumbiaVancouver V6Z 2K5BCCanada

Minimally invasive innovations have transformed *** to colorectal cancer(CRC),there has been a shift towards less invasive surgical techniques and use of endoscopic resection as an alternative for low risk t1 *** role of endoscopic resection is however much more extensive:It is now considered the first line management strategy for most large(≥20 mm)non-pedunculated colorectal polyps,the majority of which are *** is due to the well-established efficacy,safety,and cost-effectiveness of endoscopic techniques compared to *** endoscopic modalities now exist with distinct risk-benefit profiles and their outcomes are further improved by site-specific technical modifications,auxiliary techniques,and adverse event miti-gation *** capacity continues to evolve with emerging endoscopic techniques and expanding applications,particularly in the confines of a multi-disciplinary setting.

关键词： Cancer Colonoscopy Endoscopy Polyp Endoscopic mucosal resection Endoscopic submucosal dissection

Reactor field reconstruction from sparse and movable sensors using Voronoi tessellation-assisted convolutional neural networks

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Nuclear Science and techniques 2024年第5期35卷 173-185页

作者： he-Lin Gong Han Li Dunhui xiao Sibo Cheng Paris Elite Institute of technology Shanghai Jiao Tong UniversityShanghai 200240China School of Mathematical Sciences Tongji UniversityShanghai 200092China Department of Computing Data Science InstituteImperial College LondonLondon SW72AZUK

the aging of operational reactors leads to increased mechanical vibrations in the reactor *** vibration of the incore sensors near their nominal locations is a new problem for neutronic field *** field-reconstruction methods fail to handle spatially moving *** this study,we propose a Voronoi tessellation technique in combination with convolutional neural networks to handle this *** from movable in-core sensors were projected onto the same global field structure using Voronoi tessellation,holding the magnitude and location information of the *** convolutional neural networks were used to learn maps from observations to the global *** proposed method reconstructed multi-physics fields(including fast flux,thermal flux,and power rate)using observations from a single field(such as thermal flux).Numerical tests based on the IAEA benchmark demonstrated the potential of the proposed method in practical engineering applications,particularly within an amplitude of 5 cm around the nominal locations,which led to average relative errors below 5% and 10% in the L_(2) and L_(∞)norms,respectively.

关键词： Voronoi tessellation Field reconstruction Nuclear reactors Reactor physics On-line monitoring