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原子氧及紫外辐射效应对ETFE材料的降解作用
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作者 田海 把得东 +2 位作者 王鹢 冯展祖 柳青 《真空》 2026年第2期40-46,共7页
本文通过地面模拟实验研究了乙烯-四氟乙烯共聚物(ETFE)材料在低地球轨道原子氧与紫外辐照协同作用下的退化特性。测试并分析了ETFE在不同原子氧(等效能量5 eV)累积通量和紫外辐照量(波长范围200~400 nm)条件下的质量损失、表面形貌和... 本文通过地面模拟实验研究了乙烯-四氟乙烯共聚物(ETFE)材料在低地球轨道原子氧与紫外辐照协同作用下的退化特性。测试并分析了ETFE在不同原子氧(等效能量5 eV)累积通量和紫外辐照量(波长范围200~400 nm)条件下的质量损失、表面形貌和元素组成变化。结果表明材料剥蚀过程存在两阶段特征:开始阶段由剥蚀导致的材料表面化学键断裂以及挥发性产物逸出引起质量快速损失;后期材料表面形成致密的富碳层,延缓了原子氧的渗透及紫外光化学反应,剥蚀速率变慢。SEM分析表明材料经原子氧及紫外作用后表面由光滑的材料结构变成具有沟壑和孔洞的粗糙材料表面,且透光性消失。XPS分析表明,导致剥蚀减缓的主要原因是脱氟氧化、碳重构,表现为氟碳比大幅度降低。本文揭示了ETFE在低地球轨道原子氧及紫外作用下的动态退化规律,为ETFE材料的寿命评估及耐受空间环境设计提供了理论支撑。 展开更多
关键词 etfE 原子氧 紫外辐射 退化机理 航天材料
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XL-ETFE柔性电缆绝缘热机械疲劳性能的研究
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作者 霍亮 付磊 +3 位作者 李晓坤 王玉龙 张晨先 李丽丽 《电线电缆》 2026年第3期15-23,共9页
为深入探究循环载荷与温度对交联乙烯-四氟乙烯(cross-linked ethylene-tetrafluoroethylene,XLETFE)柔性电缆绝缘层疲劳寿命的影响机制,基于COMSOL有限元分析平台,耦合固体力学、固体传热和疲劳寿命模块开展仿真研究,构建航空航天用XL-... 为深入探究循环载荷与温度对交联乙烯-四氟乙烯(cross-linked ethylene-tetrafluoroethylene,XLETFE)柔性电缆绝缘层疲劳寿命的影响机制,基于COMSOL有限元分析平台,耦合固体力学、固体传热和疲劳寿命模块开展仿真研究,构建航空航天用XL-ETFE绝缘柔性电缆多物理场仿真模型。结果表明:当温度从298 K升至423 K的过程中,XL-ETFE绝缘的热应力峰值由781 MPa增至990 MPa,提高了26.76%;与此同时,最大热形变也由1060μm增至1080μm,增大了1.89%,表明温度对绝缘层力学性能具有显著影响。此外,XL-ETFE绝缘的疲劳寿命随其与机械约束距离的减小而逐渐减小,失效循环次数低至1650次;当温度升高至423 K时,失效循环次数进一步下降至1200次,降幅达27.27%,表明热应力累积与机械约束是疲劳失效的主控因素,为航空航天领域XL-ETFE绝缘柔性电缆的设计优化提供了重要的理论依据。 展开更多
关键词 航空航天用柔性电缆 XL-etfE绝缘 循环载荷 热机械性能 疲劳寿命
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国内ETF对股票波动率的影响研究
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作者 谈福嘉 《特区经济》 2026年第2期75-78,共4页
ETF作为指数基金的重要形式,是我国资本市场中的一项重要金融创新。随着国内ETF市场的快速发展,其对股票市场的影响逐渐显现,尤其是对股票波动率的影响受到越来越多的关注。然而,现有研究对于ETF持股比例如何影响股票波动率尚未形成一... ETF作为指数基金的重要形式,是我国资本市场中的一项重要金融创新。随着国内ETF市场的快速发展,其对股票市场的影响逐渐显现,尤其是对股票波动率的影响受到越来越多的关注。然而,现有研究对于ETF持股比例如何影响股票波动率尚未形成一致结论,且针对不同类型ETF以及不同市值股票的差异化影响,国内研究仍较为有限。在此背景下,本文系统考察ETF对我国股票市场的影响,并进一步分析其在不同市场结构下的表现差异,以期为ETF市场和股票市场的健康发展提供参考。 展开更多
关键词 etf持股比例 行业主题etf 股票波动率 股票市值
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ETFs组合策略的新视角
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作者 刘勤 孙玉安 《数据与计算发展前沿(中英文)》 2026年第1期27-34,共8页
【目的】在未来以ETFs(交易所交易基金,Exchange Traded Fund)为主的被动投资占主导的市场环境下,探讨一种以ETFs为标的采用板块轮动做组合投资的新视角,针对金融市场动态数据扫描,精炼使用行情关联数据,获取ETFs投资组合的有效信息,达... 【目的】在未来以ETFs(交易所交易基金,Exchange Traded Fund)为主的被动投资占主导的市场环境下,探讨一种以ETFs为标的采用板块轮动做组合投资的新视角,针对金融市场动态数据扫描,精炼使用行情关联数据,获取ETFs投资组合的有效信息,达到有效提升ETFs组合策略中长期绩效的目的。【方法】通过对全市场交易标的行情中时间、价格、量的动态扫描,以及其他信息的结合分析,揭示出ETFs标的长期与短期预期共振点作为ETFs板块轮动的触发点,结合大类资产ETFs的配置规则,搭配采用ETFs板块轮动为主的组合投资策略,控制风险与改进中长期投资绩效。【结果】可以有效改善ETFs投资的中长期风险,提高其绩效。【展望】采用更多新技术完善市场扫描效率。 展开更多
关键词 etfS 组合策略 板块轮动 流动性 预期
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Synthetic metabolic engineering of functional crops:Boosting nutrition and human health 被引量:3
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作者 Nan Chai Jie Xu +12 位作者 Ruixiang Zhang Guangzhou Li Jun Wen Liying Su Yang Xue Tie Li Jialin Liu Dongchang Zeng Jiantao Tan Jiaqi Huang Letian Chen Yao-Guang Liu Qinlong Zhu 《The Crop Journal》 2026年第1期8-21,共14页
A growing global population and the increasing prevalence of diet-related health issues such as“hidden hunger”,obesity,hypertension,and diabetes necessitate a fundamental rethinking of crop design and breeding.Synth... A growing global population and the increasing prevalence of diet-related health issues such as“hidden hunger”,obesity,hypertension,and diabetes necessitate a fundamental rethinking of crop design and breeding.Synthetic metabolic engineering offers a method to modify and redesign metabolic pathways to increase the nutritional value of crops.We summarize recent advances in the biofortification of key nutrients including provitamin A,vitamin C,vitamin B9,iron,zinc,anthocyanins,flavonoids,and unsaturated fatty acids.We discuss the potential of multi-gene stacking,gene editing,enzyme engineering,and artificial intelligence in synthetic metabolic engineering.We propose future research directions and potential solutions centered on leveraging AI-driven systems biology,precision gene editing,enzyme engineering,agrobacterium-mediated genotype-independent transformation,and modular metabolic engineering strategies to develop next-generation nutritionally enhanced super crops and transform global food systems. 展开更多
关键词 Synthetic biology Synthetic metabolism engineering functional crops Multigene stacking and gene editing Artificial intelligence
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Linking starch particle physicochemical properties to functionality in medicinal plants:Insights from Polygonum multiflorum and Smilax glabra 被引量:1
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作者 Nan Wang Lingling Wu +2 位作者 Yaya Su Haifeng Tang Hailong Yuan 《Chinese Chemical Letters》 2026年第1期487-491,共5页
This study investigates the properties of high-purity starches extracted from Polygonum multiflorum(PMS)and Smilax glabra(SGS).The starches were characterized by scanning electron microscopy,Fouriertransform infrared ... This study investigates the properties of high-purity starches extracted from Polygonum multiflorum(PMS)and Smilax glabra(SGS).The starches were characterized by scanning electron microscopy,Fouriertransform infrared spectroscopy,X-ray diffraction,high-performance anion-exchange chromatography,and differential scanning calorimetry.Significant differences were observed in their morphological,physicochemical,and functional properties.PMS had a smaller particle size(13.68 μm),irregular polygonal shape,A-type,lower water absorption(62.67 %),and higher oil absorption(51.17 %).In contrast,SGS exhibited larger particles(31.75 μm),a nearly spherical shape,B-type,higher crystallinity(50.66 %),and greater amylose content(21.54 %),with superior thermal stability,shear resistance,and gelatinization enthalpy.SGS also contained higher resistant starch(83.28 %) and longer average chain length(20.58 %),but showed lower solubility,swelling power,light transmittance,and freeze-thaw stability.The physicochemical properties differences in crystal pattern and particle morphology between PMS and SGS lead to distinct behaviors during in vitro digestion and fermentation.These findings highlight the potential of medicinal plant starches in functional ingredients and industrial processes. 展开更多
关键词 Starch particle Physicochemical properties Starch function Resistant starch Starch extraction
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The Analysis of Gauss Radial Basis Functions and Its Application in Locating Olivine on the Moon
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作者 SONG Shicang SONG Xiaoyuan SONG Shuhan 《应用数学》 北大核心 2026年第1期173-181,共9页
Gauss radial basis functions(GRBF)are frequently employed in data fitting and machine learning.Their linear independence property can theoretically guarantee the avoidance of data redundancy.In this paper,one of the m... Gauss radial basis functions(GRBF)are frequently employed in data fitting and machine learning.Their linear independence property can theoretically guarantee the avoidance of data redundancy.In this paper,one of the main contributions is proving this property using linear algebra instead of profound knowledge.This makes it easy to read and understand this fundamental fact.The proof of linear independence of a set of Gauss functions relies on the constructing method for one-dimensional space and on the deducing method for higher dimensions.Additionally,under the condition of preserving the same moments between the original function and interpolating function,both the interpolating existence and uniqueness are proven for GRBF in one-dimensional space.The final work demonstrates the application of the GRBF method to locate lunar olivine.By combining preprocessed data using GRBF with the removing envelope curve method,a program is created to find the position of lunar olivine based on spectrum data,and the numerical experiment shows that it is an effective scheme. 展开更多
关键词 Gauss function Radial basis function Machine learning Lunar olivine locating Data fitting
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Differing functions of two CYP716 genes for saikosaponin biosynthesis in Bupleurum chinense 被引量:1
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作者 Kaimi Dong Hua Chen +14 位作者 Ma Yu Shiying Wang Xue Yin Chuanxin Mo Meng Zhang Yuchan Li Yong Luo Zeru Yu Zisong Yang Jun Zhao Chao Xin Wenshuai Chen Zhen Ni Zheyong Xue Jianhe Wei 《The Crop Journal》 2026年第1期224-234,共11页
Saikosaponins are the major pharmacologically active components in Bupleurum genus and exhibit significant application potential in multiple fields such as immune regulation and anti-tumor activity.To elucidate the bi... Saikosaponins are the major pharmacologically active components in Bupleurum genus and exhibit significant application potential in multiple fields such as immune regulation and anti-tumor activity.To elucidate the biosynthetic pathway of saikosaponins,we identified two cytochrome P450 monooxygenases,CYP716A41 and CYP716Y4,in Bupleurum chinense.These enzymes catalyze the C-28 oxidation and C-16 hydroxylation of oleanane-type triterpene skeletons,respectively.The catalytic efficiency of CYP716A41 from a southern B.chinense variety was significantly higher than that from a northern variety.Molecular docking and mutagenesis experiments revealed that amino acid residues at sites 9 and 35 may contribute to this difference in catalytic efficiency.Additionally,under cold stress,the expression levels of both CYP450 genes and the saikosaponin contents in the leaves of southern varieties were significantly higher compared to those in northern varieties.The variation in the catalytic efficiency of CYP716A41 and the differential expression of the two CYP450 genes under cold stress during winter are associated with the differences in saikosaponin biosynthesis in the leaves of southern and northern B.chinense varieties.This is consistent with the distinct medicinal usage practices observed between southern and northern China. 展开更多
关键词 Bupleurum chinense Medicinal tissue utilization Saikosaponin biosynthesis pathway CYP716 functional verification
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债券型ETF高质量发展:当前格局与创新突破
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作者 马艺源 童梦瑶 《中国货币市场》 2026年第1期9-13,共5页
发展债券交易型开放式指数基金(ETF),对于做好金融“五篇大文章”、推动经济高质量发展具有重要意义。本文系统梳理了当前债券型ETF的市场格局与增长动因,重点剖析了该市场面临的三大现实问题,并就进一步释放债券ETF增长潜力、构建高质... 发展债券交易型开放式指数基金(ETF),对于做好金融“五篇大文章”、推动经济高质量发展具有重要意义。本文系统梳理了当前债券型ETF的市场格局与增长动因,重点剖析了该市场面临的三大现实问题,并就进一步释放债券ETF增长潜力、构建高质量产品体系提出相关政策建议。 展开更多
关键词 债券型etf 科创债etf 债市建设
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Microglia overexpressing brain-derived neurotrophic factor promote vascular repair and functional recovery in mice after spinal cord injury 被引量:2
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作者 Fanzhuo Zeng Yuxin Li +6 位作者 Xiaoyu Li Xinyang Gu Yue Cao Shuai Cheng He Tian Rongcheng Mei Xifan Mei 《Neural Regeneration Research》 2026年第1期365-376,共12页
Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in s... Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in spinal cord injury.Previous studies have shown that microglia can promote neuronal survival by phagocytosing dead cells and debris and by releasing neuroprotective and anti-inflammatory factors.However,excessive activation of microglia can lead to persistent inflammation and contribute to the formation of glial scars,which hinder axonal regeneration.Despite this,the precise role and mechanisms of microglia during the acute phase of spinal cord injury remain controversial and poorly understood.To elucidate the role of microglia in spinal cord injury,we employed the colony-stimulating factor 1 receptor inhibitor PLX5622 to deplete microglia.We observed that sustained depletion of microglia resulted in an expansion of the lesion area,downregulation of brain-derived neurotrophic factor,and impaired functional recovery after spinal cord injury.Next,we generated a transgenic mouse line with conditional overexpression of brain-derived neurotrophic factor specifically in microglia.We found that brain-derived neurotrophic factor overexpression in microglia increased angiogenesis and blood flow following spinal cord injury and facilitated the recovery of hindlimb motor function.Additionally,brain-derived neurotrophic factor overexpression in microglia reduced inflammation and neuronal apoptosis during the acute phase of spinal cord injury.Furthermore,through using specific transgenic mouse lines,TMEM119,and the colony-stimulating factor 1 receptor inhibitor PLX73086,we demonstrated that the neuroprotective effects were predominantly due to brain-derived neurotrophic factor overexpression in microglia rather than macrophages.In conclusion,our findings suggest the critical role of microglia in the formation of protective glial scars.Depleting microglia is detrimental to recovery of spinal cord injury,whereas targeting brain-derived neurotrophic factor overexpression in microglia represents a promising and novel therapeutic strategy to enhance motor function recovery in patients with spinal cord injury. 展开更多
关键词 ANGIOGENESIS apoptosis brain-derived neurotrophic factor colony stimulating factor 1 receptor inflammation MICROGLIA motor function spinal cord injury vascular endothelial growth factor
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Nickel-Catalyzed Borylation of Aryl Nonaflates for the Efficient Synthesis of Arylboronates via C—O Bond Functionalization
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作者 Liang Yuan Gui Chao +3 位作者 Wang Wenwen Chu Xueqiang Xu Hao Shen Zhiliang 《有机化学》 北大核心 2026年第1期207-214,共8页
Nickel-catalyzed borylation of aryl nonaflates with B2pin2 could be realized,which proceeded effectively by means of C—O bond functionalization to afford a wide variety of valuable arylboronates in moderate to excell... Nickel-catalyzed borylation of aryl nonaflates with B2pin2 could be realized,which proceeded effectively by means of C—O bond functionalization to afford a wide variety of valuable arylboronates in moderate to excellent yields with good functionality compatibility.In addition,the gram-scale synthesis and the application of the approach in the late-stage elaboration of aryl nonaflate derived from pterostilbene could also be achieved. 展开更多
关键词 nickel catalysis BORYLATION aryl nonaflates arylboronates C-O bond functionalization
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The Asymptotic Distribution of General Divisor Problem Associated to Dedekind Zeta Function over Certain Sequences
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作者 HUA Guodong 《数学进展》 北大核心 2026年第2期292-314,共23页
Let K_(j)/Q,1≤j≤ν,ν≥2 be quadratic fields with pairwise coprime discriminants Dj,and let τ_(kj)^(K_(j))(n)be the divisor function associated to Dedekind zeta function SK_(j)(s).In this paper,we consider a multid... Let K_(j)/Q,1≤j≤ν,ν≥2 be quadratic fields with pairwise coprime discriminants Dj,and let τ_(kj)^(K_(j))(n)be the divisor function associated to Dedekind zeta function SK_(j)(s).In this paper,we consider a multidimensional general divisor problem related to the τ_(kj)^(K_(j))(n)involving several number fields over square integers,by establishing the corresponding asymptotic formula.As an application,we also obtain the asymptotic formula of variance of these coefi icients. 展开更多
关键词 non-normal cubic field Dekekind zeta function divisor problem
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Effect of sitagliptin-metformin combined with nifedipine on blood pressure,blood glucose,and vascular endothelial function in patients with hypertension and type 2 diabetes mellitus
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作者 YANG Li-fei 《South China Journal of Cardiology》 2025年第4期276-283,共8页
Background The co-existence of Type 2 diabetes mellitus(T2DM)and hypertension presents a significant clinical challenge due to their synergistic detrimental effects on cardiovascular outcomes.Conventional combination ... Background The co-existence of Type 2 diabetes mellitus(T2DM)and hypertension presents a significant clinical challenge due to their synergistic detrimental effects on cardiovascular outcomes.Conventional combination therapies often fall short in comprehensively addressing the intertwined pathophysiologies,particularly vascular endothelial dysfunction.This study aimed to evaluate the efficacy of a novel regimen combining sitagliptin-metformin with nifedipine in managing blood pressure,blood glucose,and vascular function in this high-risk population.Methods 150 patients with T2DM and hypertension were randomly assigned to either the control group(n=75)treated with metformin and nifedipine,or the experimental group(n=75)treated with sitagliptin-metformin compound preparation combined with nifedipine.Changes in blood pressure,blood glucose levels,flow-mediated dilation(FMD)and nitroglycerin-mediated dilation(NMD)of the brachial artery,and serum levels of biomarkers[nitric oxide(NO),endothelin-1(ET-1)]were compared before and after treatment.The incidence of adverse reactions during treatment was also monitored.Results After treatment,both groups showed significant reductions in blood pressure,blood glucose parameters,and ET-1 levels compared to baseline.The experimental group demonstrated significantly lower values in these assessments at the same time points than control group(P<0.05).Conversely,FMD,NMD,and NO levels increased significantly in both groups after treatment,with experimental group showing significantly higher values than control group(P<0.05).There was no statistically significant difference in the incidence of adverse reactions between the two groups(P>0.05).Conclusions The combination of sitagliptinmetformin compound preparation and nifedipine significantly enhanced blood pressure control and blood glucose control and exerted a positive regulatory effect on vascular endothelial function in patients with T2DM and hypertension,demonstrating high clinical value for widespread application. 展开更多
关键词 Sitagliptin-metformin compound preparation NIFEDIPINE HYPERTENSION Type 2 diabetes mellitus Blood pressure Blood glucose Vascular endothelial function
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IMPROVEMENT ON HANKEL DETERMINANT BOUNDS FOR SPECIFIC HOLOMORPHIC FUNCTIONS
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作者 Huo TANG Muhammad ABBAS +1 位作者 Reem K.ALHEFTHI Muhammad ARIF 《Acta Mathematica Scientia》 2026年第1期39-61,共23页
In recent years,researchers have extensively investigated the Hankel determinant,which consists of coefficients appearing in a holomorphic function’s Taylor-Maclaurin series.Hankel matrices are widely used in Markov ... In recent years,researchers have extensively investigated the Hankel determinant,which consists of coefficients appearing in a holomorphic function’s Taylor-Maclaurin series.Hankel matrices are widely used in Markov processes,non-stationary signals,and other mathematical disciplines.The aim of the current research article is to first improve the bounds of coefficient-related problems by employing the well-known Carathéodory function.The problems that we are going to improve were obtained by Tang et al.The sharp estimates of the most difficult problem of geometric function theory known as the third-order Hankel determinant are also contributed here.Zalcman and Fekete-Szegöinequalities are also studied here for the defined family of holomorphic functions. 展开更多
关键词 holomorphic function Carathéodory function Hankel determinant Zalcman inequality
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The characteristics of cerebral cortical oxygenation levels and functional connectivity under upper and lower limb exercise-induced fatigue
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作者 Feng Li Yajie Wang +3 位作者 Xinyi Wang Jiawei Bi Ye Luo Lingyan Huang 《Sports Medicine and Health Science》 2026年第1期61-69,共9页
This study aims to explore the impact of fatigue induced by different limb exercises on cerebral cortical oxygenation levels and functional connectivity strength using functional near-infrared spectroscopy(fNIRS).Fati... This study aims to explore the impact of fatigue induced by different limb exercises on cerebral cortical oxygenation levels and functional connectivity strength using functional near-infrared spectroscopy(fNIRS).Fatigue was induced using an upper limb ergometer or a lower limb ergometer,with the load increasing gradually each minute.fNIRS covering the prefrontal cortex and motor cortex were used to collect data during the resting state,both before and after fatigue induction.A two-way ANOVA was conducted to examine differences in oxyhemoglobin(HbO_(2))and functional connectivity before and after fatigue induction in both groups,with the significance level set at 0.05.Exercise-induced fatigue in both the upper and lower limbs leads to a significant decrease in cerebral cortical oxygenation levels.Upper limb fatigue leads to a significant reduction in functional connectivity,there were significant decreases in connectivity within the motor cortex,between the motor cortex and frontal regions,and between the right ventrolateral prefrontal cortex and other frontal regions.Conversely,no significant changes were observed before and after lower limb fatigue.Future studies should focus on examining the extent to which how changes in the cerebral cortex,induced by exercise fatigue,are linked to exercise-and/or performance-related outcomes. 展开更多
关键词 Brain functional connectivity Cerebral oxygenation level Exercise-induced fatigue functional near-infrared spectroscopy
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Artificial intelligence in functional gastrointestinal disorders:From precision diagnosis to preventive healthcare
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作者 Yi-Nan Yan Jing-Qi Zeng Xia Ding 《Artificial Intelligence in Gastroenterology》 2026年第1期20-35,共16页
Functional gastrointestinal disorders(FGIDs),including irritable bowel syndrome(IBS),functional dyspepsia(FD),and gastroesophageal reflux disease(GERD),present persistent diagnostic and therapeutic challenges due to s... Functional gastrointestinal disorders(FGIDs),including irritable bowel syndrome(IBS),functional dyspepsia(FD),and gastroesophageal reflux disease(GERD),present persistent diagnostic and therapeutic challenges due to symptom heterogeneity and the absence of reliable biomarkers.Artificial intelligence(AI)enables the integration of multimodal data to enhance FGID management through precision diagnostics and preventive healthcare.This minireview summarizes recent advancements in AI applications for FGIDs,highlighting progress in diagnostic accuracy,subtype classification,personalized interventions,and preventive strategies inspired by the traditional Chinese medicine concept of“treating the undiseased”.Machine learning and deep learning algorithms have demonstrated value in improving IBS diagnosis,refining FD neuro-gastrointestinal subtyping,and screening for GERD-related complications.Moreover,AI supports dietary,psychological,and integrative medicine-based interventions to improve patient adherence and quality of life.Nonetheless,key challenges remain,including data heterogeneity,limited model interpretability,and the need for robust clinical validation.Future directions emphasize interdisciplinary collaboration,the development of multimodal and explainable AI models,and the creation of patientcentered platforms to facilitate a shift from reactive treatment to proactive prevention.This review provides a systematic framework to guide the clinical application and theoretical innovation of AI in FGIDs. 展开更多
关键词 Artificial intelligence functional gastrointestinal disorders Irritable bowel syndrome functional dyspepsia Gastroesophageal reflux disease
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A Robust Damage Identification Method Based on Modified Holistic Swarm Optimization Algorithm and Hybrid Objective Function
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作者 Xiansong Xie Xiaoqian Qian 《Structural Durability & Health Monitoring》 2026年第2期235-259,共25页
Correlation function of acceleration responses-based damage identificationmethods has been developed and employed,while they still face the difficulty in identifying local orminor structural damages.To deal with this ... Correlation function of acceleration responses-based damage identificationmethods has been developed and employed,while they still face the difficulty in identifying local orminor structural damages.To deal with this issue,a robust structural damage identification method is developed,integrating a modified holistic swarm optimization(MHSO)algorithm with a hybrid objective function.The MHSO is developed by combining Hammersley sequencebased population initialization,chaotic search around the worst solution,and Hooke-Jeeves pattern search around the best solution,thereby improving both global exploration and local exploitation capabilities.A hybrid objective function is constructed by merging acceleration correlation function-based and strain correlation function-based objective functions,effectively leveraging the complementary sensitivities of global and local responses.To further suppress spurious solutions and promote sparsity in parameter estimation,an additional L0.5 regularization term is introduced.The effectiveness of the proposed method is validated through numerical simulations on a simply supported beam and a steel girder benchmark structure.Comparative studies with sequential quadratic programming,genetic algorithm,andHSO demonstrate that theMHSOachieves superior accuracy and convergence efficiency,even with limited sensors and 20%noise-contaminated measurements.Results highlight that the hybrid objective function significantly enhances the detection of both major and minor damages,while the inclusion of sparse regularization improves robustness against noise and model uncertainties.The findings indicate that the proposed framework provides a reliable and computationally efficient solution for simultaneous localization and quantification of structural damages,offering promising applicability to real-world structural health monitoring scenarios. 展开更多
关键词 Damage identification holistic swarm optimization algorithm combined correlation function hybrid objective function sparse regularization grid structure
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A Benchmark Study of Density Functional Theory(DFT)Methods for Mo-Catalyzed Carbonyl Oxidative Addition
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作者 Chen Zitong Wang Liwei +1 位作者 Shen Xiao Qi Xiaotian 《有机化学》 北大核心 2026年第2期507-514,共8页
In molybdenum chemistry,the oxidative addition of o-quinone or 1,2-dicarbonyl compounds to molybdenum has been widely used in Mo-catalyzed C—C bond construction.The carbonyl oxidative addition to Mo(0)or Mo(Ⅱ)is the... In molybdenum chemistry,the oxidative addition of o-quinone or 1,2-dicarbonyl compounds to molybdenum has been widely used in Mo-catalyzed C—C bond construction.The carbonyl oxidative addition to Mo(0)or Mo(Ⅱ)is the critical elementary reaction of molybdenum catalysis.However,the relevant density functional theory(DFT)studies are relatively scarce,especially regarding the rational selection of functionals.In this work,14 functionals were employed to investigate the Mo-catalyzed carbonyl oxidative addition step.A benchmark study was carried out to evaluate their performance in structure optimization and energy calculation.Analyses of mean absolute error(MAE)and mean squared error(MSE)indicated that the B3LYP-D3(BJ),TPSSh,and ωB97X-D functionals exhibited superior performance in structure optimization.Using the DLPNO-CCSD(T)functional as the reference,the M06,M06-L,and MN15-L functionals exhibited good performance for energy calculation based on the structures optimized using the B3LYP-D3(BJ)functional.In particular,MN15-L provided the best performance with the smallest MAE and MSE. 展开更多
关键词 molybdenum catalysis carbonyl oxidation addition density functional theory(DFT)calculation DFT benchmark study
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Functional genes associated with the occurrence of mycotoxins produced by Aspergillus in foods
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作者 Mei Gu Can Liu +4 位作者 Xiaofeng Yue Du Wang Xiaoqian Tang Qi Zhang Peiwu Li 《Journal of Integrative Agriculture》 2026年第2期585-601,共17页
Aspergillus species are ubiquitous fungi that produce mycotoxins(secondary metabolites)known as sterigmatocystin and aflatoxins in many different kinds of foods,which leads to serious contamination in agricultural pro... Aspergillus species are ubiquitous fungi that produce mycotoxins(secondary metabolites)known as sterigmatocystin and aflatoxins in many different kinds of foods,which leads to serious contamination in agricultural products,thereby endangering human health.Extensive studies on Aspergillus fungi have been conducted on growth and development,aflatoxin biosynthesis,and their interactions with environment.Here,we summarized a series of functional genes of the main Aspergillus fungi relative to toxins occurrence in foods,which revealed the signal transduction mechanisms of their involvement in growth and development,toxin production,and response to light,anticipating providing theoretical guidance on developing control and prevention technologies for mycotoxin contamination in agricultural products to ensure food safety. 展开更多
关键词 functional genes ASPERGILLUS AFLATOXIN DEVELOPMENT
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