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First observation results of Macao science Satellite-1 on lightning-induced electron precipitation

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science China Earth sciences 2025年第1期68卷 1-10页

作者： Yongping WANG Yixin SUN Qiugang ZONG Gaopeng LU Xudong GU Ze-Jun HU Bin LI Key Laboratory for Polar science Ministry of Natural ResourcesPolar Research Institute of ChinaShanghai 200136China Institute of Space Physics and Applied Technology Peking UniversityBeijing 100871China State Key Laboratory of Lunar and Planetary science Macao University of Science and TechnologyMacao 999078China School of Earth and Space sciences University of Science and Technology of ChinaHefei 230026China School of Electronic Information Wuhan UniversityWuhan 430072China

The Medium-energy Electron Spectrometers(MES)is a space-borne instrument onboard Macao science Satellite-1(MSS-1)dedicated to monitoring the typical charged particle radiation characteristics in the satellite orbit and the process of their occurrence and development,including short bursts of lightning-induced electron precipitation(LEP).This paper presents the first results of the LEP measurements by the MSS-1.47 LEP events are identified with the routine operation for 3 months since satellite launch,all within the range of 1.5

关键词： Lightning-induced electron precipitation Inner radiation belts Energetic electrons Macao science Satellite-1

Radiation belt electron wisp inside South Atlantic Anomaly due to terrestrial VLF transmitter observed by MSS-1

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science China Earth sciences 2025年第2期68卷 538-548页

作者： Yixin SUN Ying LIU Qiugang ZONG Yixin HAO Hong ZOU Yuguang YE Institute of Space Physics and Applied Technology Peking UniversityBeijing 100871China State Key Laboratory of Lunar and Planetary science Macao University of Science and TechnologyMacao 999078China Max Planck Institute for Solar System Research Goettingen 37077Germany

The South Atlantic Anomaly represents a region within near-Earth space characterized by a significantly weaker geomagnetic field and a higher flux of energetic particles compared to other areas. It is a space weather hazards to Low-EarthOrbit satellites. There has been evidence that the Very Low Frequency(VLF) waves from the powerful ground VLF radio transmitter in Australia, known as NWC, have the capacity to scatter energetic electrons' pitch angle in the inner radiation *** scattering directs electrons into the drift loss cone, forms a “wisp”, characterized by its peak intensity outside the South Atlantic Anomaly(SAA), and a “rift” exhibiting minimal intensity within SAA. Our findings mark the initial observation of a“wisp” precipitation, an unusual occurrence with peak intensity detected inside the SAA, observed via the Macao science Satellite-1. Enabled by the Medium-energy Electron Spectrometer onboard Macao science Satellite-1, we were able to comprehensively measure the full pitch angle distribution at Low-Earth-Orbit. This allowed us to attribute the “wisp” within the anomaly to a specific pitch angle range just outside the drift loss cone, a measurement unattainable by previous satellites. This“wisp” occurrence aligns with previous model predictions, despite being overlooked. Moreover, we distinguished between the trapped and precipitating electron populations. Directly derived from the ratio of these populations, our analysis revealed that approximately 2%-5% of trapped electrons will be lost in this specific wisp due to the influence of the ground VLF *** results not only complement existing evidence of energetic electron pitch angle scattering facilitated by the ground VLF transmitter but also offer a quantitative estimation of its impact.

关键词： South Atlantic Anomaly Radiation belts Electrons precipitation VLF transmitter Wave-particle interaction

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Classification and identification of risk factors for type 2 diabetes

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World Journal of Diabetes 2025年第2期16卷 5-27页

作者： Shan-Shan Tang Xue-Fei Zhao Xue-Dong An Wen-Jie Sun Xiao-Min Kang Yu-Ting Sun Lin-Lin Jiang Qing Gao Ze-Hua Li Hang-Yu Ji Feng-Mei Lian College of Traditional chinese Medicine Changchun University of Chinese MedicineChangchun 130117Jilin ProvinceChina Department of Endocrinology Guang’anmen HospitalBeijing 100053China

The risk factors for type 2 diabetes mellitus(T2DM)have been increasingly researched,but the lack of systematic identification and categorization makes it difficult for clinicians to quickly and accurately access and understand all the risk factors,which are categorized in this paper into five categories:Social determinants,lifestyle,checkable/testable risk factors,history of illness and medication,and other factors,which are discussed in a narrative ***,this paper points out the problems of the current research,helps to improve the systematic categorisation and practicality of T2DM risk factors,and provides a professional research basis for clinical practice and industry decision-making.

关键词： Type 2 diabetes mellitus Risk factors Classification Prevention Narrative synthesis

Tuning the ion-dipole interactions between fluoro and carbonyl(EC)by electrolyte design for stable lithium metal batteries

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chinese Chemical Letters 2025年第1期36卷 579-584页

作者： Guihuang Fang Ying Liu Yangyang Feng Ying Pan Hongwei Yang Yongchuan Liu Maoxiang Wu Faculty of Metallurgy and Energy Engineering Kunming University of Science and TechnologyKunming 650093China Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Ethylene carbonate(EC)is the conventional and promising solvent to achieve high energy lithium metal ***,the innate low energy level of lowest unoccupied molecular orbital(LUMO)in EC makes it incompatible with lithium metal,causing uncontrolled lithium growth and low Coulombic efficiency(CE).Herein,we introduced bis(2,2,2-trifluoroethyl)carbonate(TFEC),a carbonate with a strong electron-withdrawing effect(-CF_(3)),which enhances the stability of EC at electrode interface by reducing ion-dipole interactions between Li^(+)and *** the interaction between Li and EC weakens,TFEC and more PF_(6)^(-)anions coordinate with Li^(+),promoting the formation of contact ion pairs(CIPs)and aggregates(AGGs),thereby increasing the inorganic composition within the solid electrolyte ***,the distinct solvated sheath structure favors the decomposition of fluorinated solvents and PF_(6)^(-)anions,forming inorganic-rich electrode-electrolyte interfaces(SEI and CEI),thereby ensuring high stability for both the Li anode and high-voltage ***,when applied in the full-cell Li||LiMn_(0.8)Fe_(0.2)PO_(4),it displays consistent cycling performance,exhibiting minimal capacity decay with a retention rate of 62.5%after800 cycles,substantially surpassing that of cells using base electrolytes(29.8%).

关键词： Lithium-ion batteries LiMn_(0.8)Fe_(0.2)PO_(4) High-voltage Solvation structure Ethylene carbonate Bis(2,2,2-trifluoroethyl)carbonate

Qishen Granules Modulate Metabolism Flexibility Against Myocardial Infarction via HIF-1 α-Dependent Mechanisms in Rats

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chinese JOURNAL OF INTEGRATIVE MEDICINE 2025年第3期31卷 215-227页

作者： Sun, Xiao-qian Li, Xuan Li, Yan-qin Lu, Xiang-yu Liu, Xiang-ning Cui, Ling-wen Wang, Gang Zhang, Man Li, Chun Wang, Wei Beijing Univ chinese Med Sch Tradit Chinese Med Beijing 100029 Peoples R China Beijing Univ chinese Med Beijing Key Lab Tradit Chinese Med Syndrome & Form Beijing 100029 Peoples R China Beijing Univ chinese Med Sch Chinese Mat Med Beijing 100029 Peoples R China Guangzhou Univ chinese Med Guangzhou 510006 Guangdong Peoples R China

ObjectiveTo assess the cardioprotective effect and impact of Qishen Granules (QSG) on different ischemic areas of the myocardium in heart failure (HF) rats by evaluating its metabolic pattern, substrate utilization, and mechanistic modulation. MethodsIn vivo, echocardiography and histology were used to assess rat cardiac function;positron emission tomography was performed to assess the abundance of glucose metabolism in the ischemic border and remote areas of the heart;fatty acid metabolism and ATP production levels were assessed by hematologic and biochemical analyses. The above experiments evaluated the cardioprotective effect of QSG on left anterior descending ligation-induced HF in rats and the mode of energy metabolism modulation. In vitro, a hypoxia-induced H9C2 model was established, mitochondrial damage was evaluated by flow cytometry, and nuclear translocation of hypoxia-inducible factor-1 alpha (HIF-1 alpha) was observed by immunofluorescence to assess the mechanism of energy metabolism regulation by QSG in hypoxic and normoxia conditions. ResultsQSG regulated the pattern of glucose and fatty acid metabolism in the border and remote areas of the heart via the HIF-1 alpha pathway, and improved cardiac function in HF rats. Specifically, QSG promoted HIF-1 alpha expression and entry into the nucleus at high levels of hypoxia (P<0.05), thereby promoting increased compensatory glucose metabolism;while reducing nuclear accumulation of HIF-1 alpha at relatively low levels of hypoxia (P<0.05), promoting the increased lipid metabolism. ConclusionsQSG regulates the protein stability of HIF-1 alpha, thereby coordinating energy supply balance between the ischemic border and remote areas of the myocardium. This alleviates the energy metabolism disorder caused by ischemic injury.

关键词： Qishen Granules substrate utilization hypoxia-inducible factor-1 alpha pathway energy metabolism heart failure

Simulations of electron zebra stripes in the inner radiation belt using a composite empirical electric field model

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science China Earth sciences 2025年第1期68卷 27-38页

作者： Ziyang WANG Ying LIU Qiugang ZONG Hong ZOU Yuguang YE Xuzhi ZHOU Chao YUE Shan WANG Institute of Space Physics and Applied Technology Peking UniversityBeijing100871China State Key Laboratory of Lunar and Planetary science Macao University of Science and TechnologyMacao999078China

The phenomenon termed“zebra stripes”manifests as regular patterns in the energy-space(L shell)spectrum of energetic electrons(ranging from tens to hundreds ke V)within the inner radiation *** structures exhibit drift-periodic behavior and commonly arise from large-scale electric field perturbations near the substorm *** this study,we introduce a composite electric field model and replicate the formation,structure,and evolution of zebra stripes using a bounce-averaged test particle code under this electric field ***-resolution measurements of energetic electrons obtained from the Van Allen Probes and the recently launched Macao science Satellites-1 are used as initial conditions and served to validate our test particle *** analyses between observed data and simulations demonstrate our test particle method's efficacy in capturing zebra stripes'general ***,the composite model proves capable of reproducing realistic variations in the electric field within the inner radiation belt to a certain ***,subtle differences emerge in the flux strength and the positions of *** disparities primarily stem from limitations inherent in the electric field model and the initial conditions of the *** that the model represents an average case,it is conceivable that real-world scenarios may deviate from the average,thereby introducing variations in the observed phenomena.

关键词： Zebra stripes Inner radiation belt Large-scale electric fields Van Allen Probes Macao science Satellite

The role of sulfur cycle in new particle formation:Cycloaddition reaction of SO_(3)to H_(2)S

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Journal of Environmental sciences 2025年第2期148卷 489-501页

作者： Haijie Zhang Wei Wang Liang Fan Junling Li Yanqin Ren Hong Li Rui Gao Yisheng Xu State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Key Laboratory of Cluster science Ministry of Education of ChinaSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China

The chemistry of sulfur cycle contributes significantly to the atmospheric nucleation process,which is the first step of new particle formation(NPF).In the present study,cycloaddition reaction mechanism of sulfur trioxide(SO_(3))to hydrogen sulfide(H_(2)S)which is a typical air pollutant and toxic gas detrimental to the environment were comprehensively investigate through theoretical calculations and Atmospheric Cluster Dynamic Code ***-phase stability and nucleation potential of the product thiosulfuric acid(H_(2)S_(2)O_(3),TSA)were further analyzed to evaluate its atmospheric *** any catalysts,the H_(2)S+SO_(3)reaction is infeasible with a barrier of 24.2 kcal/*** nucleation precursors formic acid(FA),sulfuric acid(SA),and water(H_(2)O)could effectively lower the reaction barriers as catalysts,even to a barrierless reaction with the efficiency of cis-SA>trans-FA>trans-SA>H_(2)***,the gas-phase stability of TSA was investigated.A hydrolysis reaction barrier of up to 61.4 kcal/mol alone with an endothermic isomerization reaction barrier of 5.1 kcal/mol under the catalytic effect of SA demonstrates the sufficient stability of ***,topological and kinetic analysis were conducted to determine the nucleation potential of *** clusters formed by TSA and atmospheric nucleation precursors(SA,ammonia NH_(3),and dimethylamine DMA)were thermodynamically ***,the gradually decreasing evaporation coefficients for TSA-base clusters,particularly for TSA-DMA,suggests that TSA may participate in NPF where the concentration of base molecules are relatively *** present new reaction mechanismmay contributes to a better understanding of atmospheric sulfur cycle and NPF.

关键词： New particle formation(NPF) Atmospheric sulfur cycle Nucleation process Reaction mechanism Hydrogen sulfide(H_(2)S) Atmospheric Cluster Dynamic Code (ACDC)

Mercury contents and potential exposure risk of rice-containing food products

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Journal of Environmental sciences 2025年第2期148卷 683-690页

作者： Xin Wang Yingjun Wang Yaqi Zhang Ziyan Liu Xiaomeng Ji Yong Cai Shandong Key Laboratory of Environmental Processes and Health School of Environmental Science and EngineeringShandong UniversityQingdao 266237China Department of Chemistry&Biochemistry Florida International UniversityMiamiFL 33199USA

Mercury(Hg),especially methylmercury(MeHg),accumulation in rice grain due to rice paddy possessing conditions conducive to Hg methylation has led to human Hg exposure through consumption of rice-based daily *** addition to being a food staple,rice is widely used as a raw material to produce a vast variety of processed food *** is known about Hg levels in snacking rice-food products and potential Hg exposure from consumption of them,besides previous studies on infant rice *** to provide complementary information for a more complete assessment on Hg exposure risk originated from Hgcontaining rice,this study determined total Hg(THg)and MeHg levels in 195 rice-containing and rice-free processed food products covering all major types of snack foods marketed in China and the estimated daily intake(EDI)of dietary Hg from the consumption of these *** results clearly showed THg and MeHg contents in rice-containing foods were significantly higher than rice-free products,suggesting the transfer of Hg and MeHg from the rice to the end products,even after manufacturing ***,significant positive correlations were observed between THg,MeHg,or MeHg/THg ratio and rice content for samples containing multiple grains as ingredients,further indicating the deciding role of rice for Hg levels in the end food *** the EDI of THg and MeHg via ricebased food products were relatively low compared to the reference dose,it should be considered these snacking food products would contribute additive Hg intake outside of the daily regular meals.

关键词： Mercury Methylmercury Processed food products Rice Dietary exposure

Na_(2)B_(6)SO_(13) with unprecedented [B_(6)SO_(13)]_(∞) double chains and largest birefringence among borosulfates induced by the uniform arrangement of [B_(3)O_(7)] units

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science China Chemistry 2025年第2期68卷 475-480页

作者： Jinbin Fan Ziting Yan Zilong Chen Huimin Li Zhihua Yang Fangfang Zhang Shilie Pan Research Center for Crystal Materials State Key Laboratory of Functional Materials and Devices for Special Environmental ConditionsXinjiang Key Laboratory of Functional Crystal MaterialsXinjiang Technical Institute of Physics and ChemistryChinese Academy of SciencesUrumqi 830011China Center of Materials science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Birefringence is crucial for birefringent crystals to modulate polarized light and nonlinear optical crystals to enable *** is closely related to the arrangement of advantageous functional groups with large microcosmic polarizability anisotropy in the ***,designing crystals with large birefringence by modulating the arrangement of advantageous functional groups is still a *** this work,the arrangement of the advantageous[B_(3)O_(7)]groups is optimized by introducing rigid tetrahedral[SO_(4)]groups,resulting in a novel boron-rich borosulfate,Na_(2)B_(6)SO_(13) ,which exhibits unprecedented[B_(6)SO_(13)]_(∞)double chain and an enhanced birefringence(Δn=0.07 at 589.3 nm)against the borate parent *** calculations confirm that the birefringence is mainly attributable to the uniform alignment of[B_(3)O_(7)]***_(2)B_(6)SO_(13) also possesses a deep ultraviolet(DUV)cutoff edge(λ<185 nm).This work provides a feasible method to design DUV birefringent crystals with large birefringence by inducing the arrangement of advantageous functional groups.

关键词： borosulfate deep ultraviolet birefringence modulated groups