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Calenduloside E produced by Bifidobacterium animalis B960 increases glibenclamide efficacy and alleviates drug-induced adverse effects in a type 2 diabetes model
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作者 Siyuan Shen Liting Lu +4 位作者 Haiyang Tu Shuaiming Jiang Zeng Zhang Zhe Han Jiachao Zhang 《Science Bulletin》 2026年第3期520-524,共5页
Concerns about the long-term safety and efficacy of glibenclamide(GLIB),a type 2 diabetes mellitus(T2DM)treatment,have been reported[1].Recent evidence indicates the gut microbiota composition significantly affects ho... Concerns about the long-term safety and efficacy of glibenclamide(GLIB),a type 2 diabetes mellitus(T2DM)treatment,have been reported[1].Recent evidence indicates the gut microbiota composition significantly affects host glucose metabolism and drugbioavailability,increasingthe efficacy of T2DM therapy[2].In this context,probiotic-drug coadministration,an emerging adjunct approach for treating metabolic diseases,improves therapeutic outcomes and ameliorates side effects[3]. 展开更多
关键词 treating metabolic diseasesimproves type diabetes mellitus t dm treatmenthave bifidobacterium animalis B adjunct approach calenduloside E glibenclamide efficacy ameliorates side effects drug induced adverse effects
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An overview of the advantageous effects and underlying mechanisms of natural polysaccharides in inflammatory bowel disease
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作者 Yating Shao Bo Li +6 位作者 Yongfang Wang Chuanjie Zhou Yunlong Qiao Xinglishang He Shengqiang Tong Guiyuan Lv Suhong Chen 《Chinese Journal of Natural Medicines》 2026年第1期45-58,共14页
Inflammatory bowel disease(IBD),which includes Crohn’s disease(CD)and ulcerative colitis(UC),is a chronic inflammatory condition affecting the gastrointestinal tract.The global incidence and prevalence of IBD continu... Inflammatory bowel disease(IBD),which includes Crohn’s disease(CD)and ulcerative colitis(UC),is a chronic inflammatory condition affecting the gastrointestinal tract.The global incidence and prevalence of IBD continue to increase.While multiple clinical treatments exist,conventional therapies frequently present limitations and adverse effects.Natural polysaccharides(PSs)have emerged as a significant focus of research interest due to their therapeutic potential and applications in functional foods and health products.This review synthesizes current understanding of IBD pathophysiology and the mechanisms by which natural PSs counter IBD,including their capacity to restore immune homeostasis and intestinal barrier function,modulate gut microbiota and metabolites,reduce oxidative stress,and address irregularities in autophagy and endoplasmic reticulum stress(ERS).The review examines the structure-activity relationships of PSs demonstrating anti-IBD effects and identifies promising therapeutic products.The discussion encompasses pharmacokinetics,safety evaluations,and clinical applications of these compounds.This comprehensive review establishes a theoretical foundation for developing natural PS-based therapeutic approaches for IBD management. 展开更多
关键词 Natural polysaccharides Inflammatory bowel disease PATHOGENESIS Therapeutic effect Research progress
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Correction models of Reynolds number effects for through-flow method in axial compressors
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作者 Xiaochen WANG Chunwei GU 《Chinese Journal of Aeronautics》 2026年第1期78-94,共17页
Aerodynamic performances of axial compressors are significantly affected by variation of Reynolds number in aero-engines.In the design and analysis of compressors,previous correction methods for cascades and stages ha... Aerodynamic performances of axial compressors are significantly affected by variation of Reynolds number in aero-engines.In the design and analysis of compressors,previous correction methods for cascades and stages have difficulties in predicting comprehensively Reynolds number effects on airfoils,matching and characteristics curves.This study proposes Re-correction models for loss,deviation angle and endwall blockage based on classical theories and cascade tests,and loss and deviation models show good agreement in test data of NACA65 and C4 cascades.Throughflow method considering Reynolds number effects is developed by integrating the correction models into a verified Streamline Curvature(SLC)tool.A three-stage axial compressor is investigated through SLC and CFD methods from design Reynolds number(Red=2106)to low Re=4104,and the numerical methods are validated with test data of characteristic curves and spanwise distributions at Red.With Re reduction,SLC method with correction models well predicts variation in overall performances compared with CFD calculations and Wassell's model.Streamwise and spanwise matching such as total pressure and loss distributions in SLC predictions are basically consistent with those in CFD results at near-stall points under design and low Reynolds numbers.SLC and CFD methods share similar detections of stall risks in the third stage(Stg3),and their analyses of diffusion processes deviate to some extent due to different predictions in separated endwall flow.The correction models can be adopted to consider Reynolds number effects in through-flow design and analysis of axial compressors. 展开更多
关键词 Axial compressor Reynolds number effects Correction model Through-flow method Aerodynamic performance
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From ancient herb to modern miracle:an in-depth analysis of the cardioprotective effects of artemisinin and its derivatives
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作者 Hao-Shuang LI Shu-Rong LI +6 位作者 Wen-Jue LIU Yuan ZHANG Rui WU Xu-Yang CUI Jia-Zheng SUN You-Wei MA Ying ZHAO 《Journal of Geriatric Cardiology》 2026年第1期45-64,共20页
Significant progress has been recently made in studying artemisinin and its derivatives for treating cardiovascular diseases,making this area a prominent research focus.Artemisinin,discovered with great acclaim,was in... Significant progress has been recently made in studying artemisinin and its derivatives for treating cardiovascular diseases,making this area a prominent research focus.Artemisinin,discovered with great acclaim,was initially and widely adopted in antimalarial treatments.As scientific research steadily progressed,its latent potential role in the cardiovascular system gradually captured the attention of the global scientific community.Artemisinin and its derivatives can reportedly play a protective role in the cardiovascular system through various mechanisms,including anti-inflammatory,anti-angiogenic,antioxidant,and anti-fibrotic effects,as well as the regulation of blood lipids and blood pressure.In particular,they have shown promising therapeutic effects in models of cardiovascular diseases such as atherosclerosis,myocardial ischaemia,and cardiac hypertrophy.In addition,artemisinin and its derivatives can improve cardiovascular function and prevent cardiovascular injury by regulating signalling pathways closely related to cardiovascular disease,such as AMPK and NF-kB.Although numerous ex vivo and in vivo experiments have verified the potential role of artemisinin in treating cardiovascular diseases,systematic studies to comprehensively elucidate its specific mechanism of action remain scarce.Further exploration of the precise roles of artemisinin and its derivatives in cardiovascular disease therapy,along with their potential clinical applications,could offer valuable insights for future research and treatment strategies. 展开更多
关键词 antimalarial treatmentsas ARTEMISININ cardiovascular diseasesmaking myocardial ischemia cardiac hypertrophy cardiovascular system cardioprotective effects ATHerOSCLerOSIS
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Damage evolution and constitutive model of limestone with horizontal fissure under the coupled effects of dry-wet cycling and precompression stress
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作者 Shunbo Zhang Zhongping Yang +2 位作者 Yang Gao Miao Liu Shanmeng Hou 《International Journal of Mining Science and Technology》 2026年第1期205-228,共24页
To reveal the influence of coupled effects of dry-wet cycling and precompression stress(CEDWCPS)on the damage evolution of limestone with horizontal fissure(LHF),a series of degradation and uniaxial compression tests ... To reveal the influence of coupled effects of dry-wet cycling and precompression stress(CEDWCPS)on the damage evolution of limestone with horizontal fissure(LHF),a series of degradation and uniaxial compression tests were conducted,and a corresponding piecewise damage constitutive model(PDCM)was established.We found that both dry-wet cycling and precompression stress deteriorate the physical properties,alter the microscopic characteristics,and reduce the mechanical properties of the LHF.These degradations are particularly pronounced under the CEDWCPS,although the magnitude of these changes gradually diminishes with the progression of dry-wet cycling.Meanwhile,they also reduce the deformation degree,prolong the micropore compaction stage,shorten the unstable crack propagation stage,lower the frequency and intensity of AE events,decrease the high-amplitude and high-frequency AE signals,enlarge crack scales,and shorten the crack initiation time.Among the changes of these indicators,the dry-wet cycling plays a dominant role.The crack types of LHF under the CEDWCPS(LHFCEDWCPS)are predominantly tensile cracks,supplemented by shear cracks.The failure mode can be defined as tensileshear composite failure.Finally,the established PDCM effectively captures the nonlinear deformation of micropore and the linear deformation of the matrix in LHFCEDWCPS,with all corresponding R^(2) consistently exceeding 0.97. 展开更多
关键词 Dry-wet cycling Precompression stress Coupled effect Fractured limestone Damage evolution Damage constitutive model
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Effects of confinedaquifer on water-sand gushing disasters in soft soil
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作者 Liangjin Li Yafei Qiao +1 位作者 Jinchun Chai Wenqi Ding 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1126-1137,共12页
Water-sand gushing(WSG)disasters in confinedaquifers pose significantchallenges to the utilization of deep underground spaces in soft soil areas.Since few studies have considered the impact of confined aquifer thickne... Water-sand gushing(WSG)disasters in confinedaquifers pose significantchallenges to the utilization of deep underground spaces in soft soil areas.Since few studies have considered the impact of confined aquifer thickness and confinedwater pressure on WSG disasters,a novel visual model test system was developed to investigate the influencingcharacteristics and mechanisms of the two aforementioned factors.The test results showed that the WSG process in clay aquiclude-confinedaquifer composite strata exhibits two prominent stages.First,the sand loss zone expands vertically in an ellipsoid shape.Then,it expands horizontally once the ellipsoid reaches the boundary of the clay layer.The sand loss continues until the overlying clay sinks to the bottom to clog the gushing crack,creating a large sinkhole at the surface.Increasing the confinedaquifer thickness can increase the vertical expansion of the ellipsoid and delay the clay-clogging effects,thereby considerably increasing the severity of sand loss,stratum deformation,and surface settlement.An increase in the confinedwater pressure markedly increases the hydraulic gradient along the seepage path,which contributes to increasing the gushing rates of water and sand.As a result,substantial sand loss occurs before the clay clogs the gushing crack,inducing more cracks and deeper sinkholes at the surface.All the aforementioned results provide insights into the effects of confinedaquifer on WSG disasters in clay aquiclude-confinedaquifer composite strata. 展开更多
关键词 Water-sand gushing(WSG)disasters Confinedaquifer thickness Confinedwater pressure Beam-bearing mechanism Clay-clogging effects Model test
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Lithium Nitrate Effects for Lithium-Based Chemical Batteries:A Review
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作者 Xianshu Wang Junru Wu +6 位作者 Huirong Wang Xiangshao Yin Zhuo Zhou Yuanyuan Huang Yelong Zhang Weishan Li Baohua Li 《Carbon Energy》 2026年第1期197-222,共26页
Lithium metal batteries(LMBs)have been regarded as one of the most promising alternatives in the post-lithium battery era due to their high energy density,which meets the needs of light-weight electronic devices and l... Lithium metal batteries(LMBs)have been regarded as one of the most promising alternatives in the post-lithium battery era due to their high energy density,which meets the needs of light-weight electronic devices and long-range electric vehicles.However,technical barriers such as dendrite growth and poor Li plating/stripping reversibility severely hinder the practical application of LMBs.However,lithium nitrate(LiNO_(3))is found to be able to stabilize the Li/electrolyte interface and has been used to address the above challenges.To date,considerable research efforts have been devoted toward understanding the roles of LiNO_(3) in regulating the surface properties of Li anodes and toward the development of many effective strategies.These research efforts are partially mentioned in some articles on LMBs and yet have not been reviewed systematically.To fill this gap,we discuss the recent advances in fundamental and technological research on LiNO_(3) and its derivatives for improving the performances of LMBs,particularly for Li-sulfur(S),Li-oxygen(O),and Li-Li-containing transition-metal oxide(LTMO)batteries,as well as LiNO_(3)-containing recipes for precursors in battery materials and interphase fabrication.This review pays attention to the effects of LiNO_(3) in lithium-based batteries,aiming to provide scientific guidance for the optimization of electrode/electrolyte interfaces and enrich the design of advanced LMBs. 展开更多
关键词 effects and mechanisms LiNO_(3)derivatives LiNO_(3)-containing recipes lithium metal anode Lithium nitrate basis lithium-based chemical batteries
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High-speed Rail Accessibility and Spatial Effects of Primorsky No.1 and No.2 International Transportation Corridors
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作者 CHU Nanchen ZHANG Pingyu +2 位作者 LIU Weizhong LI Yuxin LI Zhao 《Chinese Geographical Science》 2026年第1期82-96,共15页
Under the background of‘the Belt and Road’and‘China-Mongolia-Russia Economic Corridor’initiatives,this paper studied the urban accessibility level,regional accessibility pattern and regional spatial effects along ... Under the background of‘the Belt and Road’and‘China-Mongolia-Russia Economic Corridor’initiatives,this paper studied the urban accessibility level,regional accessibility pattern and regional spatial effects along the Primorsky No.1 and No.2 transportation corridors.First,the evaluation of urban accessibility level with and without Primorsky No.1 and No.2 high-speed rails(HSRs)opening was conducted with two indicators,i.e.,the weighted average travel time,and the economic potential.After the evaluation,the spatial differentiation pattern of the accessibility changes with and without Primorsky No.1 and No.2 HSRs opening was performed respectively using ArcGIS.On these bases,the regional spatial effects brought by Primorsky No.1 and No.2 HSRs opening were studied.The results are as following.First,the urban accessibility level will be greatly improved by the opening of Primorsky No.1 and No.2 HSRs.All adjacent cities will be integrated into‘1 h HSR communication circle’and the whole journey will be integrated into‘4 h HSR communication circle’along Primorsky No.1 and No.2 corridors,respectively.The HSR accessibility of Primorsky No.1 corridor is stronger than that of Primorsky No.2 corridor.But the HSR accessibility improvement degree of Primorsky No.1 corridor is weaker than that of Primorsky No.2 corridor.Second,spatially,along Primorsky No.1 and No.2 corridors,the HSR accessibility level of the cities which are located in China is stronger than those cities located in Russia,showing the‘High West,Low East’patterns.The HSR accessibility improvement degree of the cities which are located in Russia and Sino-Russian border is stronger than those cities located in China,showing the‘High East,Low West’patterns.Third,Primorsky No.1 and No.2 corridors could connect the China’s‘Heilongjiang Land Sea Silk Road Economic Belt’and‘Changchun-Jilin-Tumen Development Pilot Zone’respectively,gradually involving into the development of China’s Harbin-Changchun Megalopolis.Relying on Harbin(China)and Changchun(China),Primorsky No.1 and No.2 HSRs could connect Northeast China-Beijing HSR,accelerating the diffusion of population,economy and other flows from China’s Beijing-Tianjin-Hebei Urban Agglomeration to Northeast China,and then to Russia’s Far East Federal District.Relying on Suifenhe(China)and Hunchun(China),Primorsky No.1 and No.2 HSRs could be conducive to the development of the second largest sea channels for Northeast China,creating the Northeast Asian Urban Belt,and new sea-rail intermodal pattern among China,Russia,Democratic People’s Republic of Korea,Japan and Republic of Korea.Relying on Vladivostok(Russia)and Zarubino(Russia),Primorsky No.1 and No.2 corridors could connect the‘Ice Silk Road’,building the‘Sino-Russian Northern Maritime Corridor’and‘Sino-Russian Arctic Blue Economic Areas’. 展开更多
关键词 ACCESSIBILITY high-speed rail(HSRs) spatial effect Primorsky No.1 transport corridor Primorsky No.2 transport corridor Vladivostok and Zarubino Russia
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Er-Yb玻璃低应力减反射膜的研制
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作者 潘永刚 袁浩春 +6 位作者 林兆文 曾彬 张功 石澎 王龙 郗梓成 付秀华 《红外与激光工程》 北大核心 2026年第1期376-385,共10页
随着激光技术的快速发展,Er-Yb玻璃在人眼安全激光器中得到广泛应用,但Er-Yb玻璃作为激光器谐振腔的基底时,表面膜层附着力差、应力大的问题降低了激光器的输出效率。采用Ta_(2)O_(5)和SiO_(2)作为高低折射率材料,利用离子辅助沉积技术,... 随着激光技术的快速发展,Er-Yb玻璃在人眼安全激光器中得到广泛应用,但Er-Yb玻璃作为激光器谐振腔的基底时,表面膜层附着力差、应力大的问题降低了激光器的输出效率。采用Ta_(2)O_(5)和SiO_(2)作为高低折射率材料,利用离子辅助沉积技术,在Er-Yb玻璃基底上研制了低应力的减反射膜。通过使用COMSOL软件建立热仿真模型,引入SiO_(2)粘接层,降低膜层热应力,解决了膜层脱膜的问题;通过设计梯度工艺参数,建立了残余应力与离子源能量和膜层厚度的数学模型,选取合适的工艺参数,制备了低应力减反射膜,在(1 535±3) nm波长平均反射率为0.069%,膜层残余应力为-8.61 MPa,并且通过了附着力、水煮及湿热试验,满足使用要求。 展开更多
关键词 减反射膜 er-Yb玻璃 离子辅助沉积 附着力 低应力
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Er和Cu复合添加对A356合金组织与力学性能的影响
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作者 汤江涛 冯丽 +3 位作者 冯恩浪 姜岳峰 梁田 马颖澈 《金属热处理》 北大核心 2026年第1期12-21,共10页
通过在A356铝合金中加入0.2%、0.4%稀土元素Er及复合添加0.1%Er、1.76%Cu,研究了Er、Cu对压铸成形A356铝合金微观组织和力学性能的影响。结果表明:加入稀土元素Er后,共晶Si的形貌由长纤维状或长棒状转变为细小的纤维状或点状结构,共晶S... 通过在A356铝合金中加入0.2%、0.4%稀土元素Er及复合添加0.1%Er、1.76%Cu,研究了Er、Cu对压铸成形A356铝合金微观组织和力学性能的影响。结果表明:加入稀土元素Er后,共晶Si的形貌由长纤维状或长棒状转变为细小的纤维状或点状结构,共晶Si的共晶转变温度及α-Al的熔化温度降低。随着Er含量的增加,合金的抗拉强度由242.0 MPa小幅升高至250.0 MPa,但伸长率由7.00%降低至5.50%。在A356铝合金中复合添加0.1%Er和1.76%Cu时,合金中形成了Al_(3)Er、Al_(8)Cu_(4)Er、Al_(2)Cu等金属间化合物,合金的抗拉强度为243.0 MPa,伸长率降低为1.50%,表明Er和Cu未表现出良好的协同强韧化作用。其主要原因是快速凝固促使富Cu相以粗大块状或团簇状在枝晶间析出,导致应力集中,并在拉伸过程中于其棱角处萌生微裂纹,从而严重恶化塑性。 展开更多
关键词 压铸态 A356合金 稀土er CU 复合协同
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锻造工艺及热处理对含Er7050铝合金组织与力学性能的影响
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作者 刘宇航 荣莉 +8 位作者 黄晖 陈炯燊 马晨曦 史晓成 魏午 文胜平 高坤元 吴晓蓝 聂祚仁 《稀有金属材料与工程》 北大核心 2026年第2期517-527,共11页
为了探究多向锻造对铝合金微观组织及力学性能的影响,以均火态含Er7050铝合金为研究对象,对该合金在400℃下进行了3种不同锻造道次的多向锻造,即三墩三拔(3U3CS)、六墩六拔(6U6CS)以及九墩九拔(9U9CS)。随后,合金经过固溶处理、水淬和T... 为了探究多向锻造对铝合金微观组织及力学性能的影响,以均火态含Er7050铝合金为研究对象,对该合金在400℃下进行了3种不同锻造道次的多向锻造,即三墩三拔(3U3CS)、六墩六拔(6U6CS)以及九墩九拔(9U9CS)。随后,合金经过固溶处理、水淬和T6时效处理。对样品进行微观结构分析和机械性能测试。通过比较3种不同锻造工艺所得样品的机械性能,发现经过九墩九拔锻造工艺处理的样品具有最佳的机械性能,这归功于该锻造工艺使其产生细小的晶粒和致密的析出强化相,该锻造工艺条件下样品的平均抗拉强度为621.4 MPa,平均屈服强度为545.4 MPa,平均伸长率为13.58%,对比其他两种锻造工艺处理的样品均有提升,这表明优化的锻造工艺显著改善了机械性能。 展开更多
关键词 er7050铝合金 多向锻造 显微组织演变 再结晶
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Photothermal effects of multidimensional confined MMC/TMs-MDCS catalyst for ultra-high photocatalytic hydrogen evolution 被引量:1
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作者 Huihua Luo Haifeng Zhu +4 位作者 Kehui Xue Chong Liu Nannan Chen Yaping Zhang Lianqing Yu 《Journal of Energy Chemistry》 2025年第5期655-669,共15页
Multidimensional confined structure systems are proposed and demonstrated by using MoO_(2)@MO_(2)C(MMC)to enhance the photothermal catalytic performance of the metal sulfides-multidimensional confined structure(TMs-MD... Multidimensional confined structure systems are proposed and demonstrated by using MoO_(2)@MO_(2)C(MMC)to enhance the photothermal catalytic performance of the metal sulfides-multidimensional confined structure(TMs-MDCS).Specifically,the MMC nanoparticles confined to the surface of the ZnIn_(2)S_(4)hollow tube-shell(MMC/HT-ZIS)achieve a hydrogen evolution rate of 9.72 mmol g^(-1)h^(-1),which is 11.2 times higher than that of pure HT-ZIS.Meanwhile,the MnCdS(MCS)nanoparticles are encapsulated within the two-dimensional MMC(2D MMC/MCS)through precise regulation of size and morphology.The 10-MMC/MCS lamellar network demonstrates the highest hydrogen evolution rate of 8.19 mmol g^(-1)-h^(-1).The obtained MMC/TMs-MDCS catalysts exhibit an enhanced photocatalytic hydrogen evolution rate,which can be attributed to the strong synergistic interaction between the multidimensional confinement and the photothermal effects.The confinement space and the strong interfacial relationship within the MMC/TMs-MDCS create abundant channels and active sites that facilitate electron migration and transport.Furthermore,the construction of a confined environment positions these materials as promising candidates for achieving exceptional photothermal catalytic performance,as MMC/TMs-MDCS enhance light absorption through light scattering and reflecting effects.Additionally,the capacity of MMC/TMsMDCS to convert solar light into thermal energy significantly reduces the activation energy of the reaction,thereby facilitating reaction kinetics and accelerating the separation and transport of photogenerated carriers.This work provides valuable insights for the development of highly efficient photothermal catalytic water-splitting systems for hydrogen production using multidimensional confined catalysts. 展开更多
关键词 Multidimensional confined effect Photothermal effect Photothermal catalytic hydrogen production
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Effects of Fruit-Crop Agroforestry Systems on Pest and Natural Enemy Diversity 被引量:1
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作者 LI Guoyu LIU Tingting +3 位作者 WEI Wenwen ZHANG Shuai LI Zhe ZHANG Wei 《绿洲农业科学与工程》 2025年第1期80-91,共12页
Agricultural intensification has led to an increase in monoculture and the use of chemical pesticides,resulting in a decline in biodiversity and a reduction in ecosystem services,particularly biological pest managemen... Agricultural intensification has led to an increase in monoculture and the use of chemical pesticides,resulting in a decline in biodiversity and a reduction in ecosystem services,particularly biological pest management.However,studies have shown that agroforestry can not only improve land productivity and biodiversity but also regulate some ecosystem services.This study reviews the impacts of physical and biological factors on herbivorous pests,parasites,and predatory natural enemies in fruit-crop agroforestry systems.Fruit-crop agroforestry systems provide high spatial heterogeneity by altering crop layouts,regulating the microclimate and soil quality,and offering food resources and shelter for natural enemies,thus promoting biological pest control.This enhances biological control and makes the agrocomplex system an effective tool for sustainable agriculture.Our research shows that volatile plant substances attract or repel pests and natural enemies based on the characteristics of the insects themselves.When scientifically designed,fruit-crop agroforestry systems provide high spatial heterogeneity and favorable microclimatic conditions,which enhance biological pest control and make the agroforestry system an effective tool for sustainable agriculture.Our research shows that fruit-crop agroforestry systems can provide richer food resources and habitat,enhancing biological pest control and improving pest management. 展开更多
关键词 AGROFORESTRY PEST natural enemy BIODIVerSITY effect factors
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Independent and interactive effects of N and P additions on foliar P fractions in evergreen forests of southern China 被引量:1
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作者 Qingquan Meng Zhijuan Shi +3 位作者 Zhengbing Yan Hans Lambers Yan Luo Wenxuan Han 《Forest Ecosystems》 2025年第1期66-73,共8页
Fertilization or atmospheric deposition of nitrogen(N)and phosphorus(P)to terrestrial ecosystems can alter soil N(P)availability and the nature of nutrient limitation for plant growth.Changing the allocation of leaf P... Fertilization or atmospheric deposition of nitrogen(N)and phosphorus(P)to terrestrial ecosystems can alter soil N(P)availability and the nature of nutrient limitation for plant growth.Changing the allocation of leaf P fractions is potentially an adaptive strategy for plants to cope with soil N(P)availability and nutrient-limiting conditions.However,the impact of the interactions between imbalanced anthropogenic N and P inputs on the concentrations and allocation proportions of leaf P fractions in forest woody plants remains elusive.We conducted a metaanalysis of data about the concentrations and allocation proportions of leaf P fractions,specifically associated with individual and combined additions of N and P in evergreen forests,the dominant vegetation type in southern China where the primary productivity is usually considered limited by P.This assessment allowed us to quantitatively evaluate the effects of N and P additions alone and interactively on leaf P allocation and use strategies.Nitrogen addition(exacerbating P limitation)reduced the concentrations of leaf total P and different leaf P fractions.Nitrogen addition reduced the allocation to leaf metabolic P but increased the allocation to other fractions,while P addition showed opposite trends.The simultaneous additions of N and P showed an antagonistic(mutual suppression)effect on the concentrations of leaf P fractions,but an additive(summary)effect on the allocation proportions of leaf P fractions.These results highlight the importance of strategies of leaf P fraction allocation in forest plants under changes in environmental nutrient availability.Importantly,our study identified critical interactions associated with combined N and P inputs that affect leaf P fractions,thus aiding in predicting plant acclimation strategies in the context of intensifying and imbalanced anthropogenic nutrient inputs. 展开更多
关键词 Anthropogenic nutrient inputs Individual and combined effects Interactive effects Leaf phosphorus fractions Nitrogen and phosphorus additions Nutrient-utilization strategies Woody plants
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Understanding the Decoupled Effects of Cations and Anions Doping for High-Performance Perovskite Solar Cells 被引量:1
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作者 Tianxiang Hu Yixi Wang +16 位作者 Kai Liu Jia Liu Haoyang Zhang Qudrat Ullah Khan Shijie Dai Weifan Qian Ruochen Liu Yanyan Wang Chongyuan Li Zhenru Zhang Mingxiang Luo Xiaofei Yue Chunxiao Cong Yuan Yongbo Anran Yu Jia Zhang Yiqiang Zhan 《Nano-Micro Letters》 2025年第6期411-426,共16页
The past decade has witnessed the rapid increasement in power conversion efficiency of perovskite solar cells(PSCs).However,serious ion migration hampers their operational stability.Although dopants composed of varied... The past decade has witnessed the rapid increasement in power conversion efficiency of perovskite solar cells(PSCs).However,serious ion migration hampers their operational stability.Although dopants composed of varied cations and anions are introduced into perovskite to suppress ion migration,the impact of cations or anions is not individually explored,which hinders the evaluation of different cations and further application of doping strategy.Here we report that a special group of sulfonic anions(like CF_(3)SO_(3)^(-))successfully introduce alkaline earth ions(like Ca^(2+))into perovskite lattice compared to its halide counterparts.Furthermore,with effective crystallization regulation and defect passivation of sulfonic anions,perovskite with Ca(CF_(3)SO_(3))_(2)shows reduced PbI2 residue and metallic Pb0 defects;thereby,corresponding PSCs show an enhanced PCE of 24.95%.Finally by comparing the properties of perovskite with Ca(CF_(3)SO_(3))_(2)and FACF_(3)SO_(3),we found that doped Ca^(2+)significantly suppressed halide migration with an activation energy of 1.246 eV which accounts for the improved operational stability of Ca(CF_(3)SO_(3))_(2-)doped PSCs,while no obvious impact of Ca^(2+)on trap density is observed.Combining the benefits of cations and anions,this study presents an effective method to decouple the effects of cations and anions and fabricate efficient and stable PSCs. 展开更多
关键词 Perovskite solar cells Interstitial doping Effect decoupling Ion migration
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Enhancing hydrogen storage performance of MgH_(2)with hollow Bi_(2)Ti_(2)O_(7)catalyst:Synergistic effects of Bi_(2)Mg_(3)alloy phase and Ti polyvalency 被引量:1
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作者 Xiaoying Yang Xinqiang Wang +7 位作者 Ruijie Liu Yanxia Liu Zhenglong Li Wengang Cui Fulai Qi Yaxiong Yang Jian Chen Hongge Pan 《Journal of Magnesium and Alloys》 2025年第12期6154-6166,共13页
The role of catalysts in enhancing the hydrogen storage kinetics of the Mg/MgH_(2)system is pivotal.However,the exploration of efficient catalysts and the underlying principles of their design remain both a prominent ... The role of catalysts in enhancing the hydrogen storage kinetics of the Mg/MgH_(2)system is pivotal.However,the exploration of efficient catalysts and the underlying principles of their design remain both a prominent focus and a significant challenge in current research.In this study,we present a bimetallic oxide of Bi_(2)Ti_(2)O_(7)hollow sphere as a highly effective catalyst for MgH_(2).As a result,the Bi_(2)Ti_(2)O_(7)-catalyzed Mg/MgH_(2)system lowers the hydrogen desorption initiation temperature to 194.3℃,reduces the peak desorption temperature to 245.6℃,decreases the dehydrogenation activation energy to 82.14 kJ·mol^(−1),and can absorb 5.4 wt.%of hydrogen within 60 s at 200℃,demonstrating outstanding hydrogen ab/desorption kinetics,compared to pure MgH_(2).Additionally,it can maintain a high hydrogen capacity of 5.2 wt.%,even after 50 dehydrogenation cycles,showing good cycle stability.The characterization results show that the high-valent Bi and Ti in Bi_(2)Ti_(2)O_(7)are reduced to their low-valent or even zero-valent metallic states during the dehydrogenation and hydrogenation process,thus establishing an in-situ multivalent and multi-element catalytic environment.Density functional theory calculations further reveal that the synergistic effects between Bi and Ti in the Bi-Ti mixed oxide facilitate the cleavage of Mg-H bonds and lower the kinetic barrier for the dissociation of hydrogen molecules,thereby substantially enhancing the kinetics of the Mg/MgH_(2)system.This study presents a strategic method for developing efficient catalysts for hydrogen storage materials by harnessing the synergistic effects of metal elements. 展开更多
关键词 Hydrogen storage MgH_(2) Bimetallic oxide CATALYSTS Synergistic effects
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Factors affecting the thermal effects of lasers in lithotripsy:A literature review 被引量:1
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作者 Kiron Krishnaprasad Ravi Teja Pathi Mustafa Nazar 《Asian Journal of Urology》 2025年第1期23-32,共10页
Objective The use of lasers has been an important part of urology in the treatment of stone and prostate disease.The thermal effects of lasers in lithotripsy have been a subject of debate over the years.The objective ... Objective The use of lasers has been an important part of urology in the treatment of stone and prostate disease.The thermal effects of lasers in lithotripsy have been a subject of debate over the years.The objective of this review was to assess the current state of knowledge available on the thermal effects of lasers in lithotripsy,as well as explore any new areas where studies are needed.Methods In August 2022,a keyword search on Google Scholar,PubMed,and Scopus for all papers containing the phrases“thermal effects”AND“laser”AND“lithotripsy”AND“urology”was done followed by citation jumping to other studies pertaining to the topic and 35 relevant papers were included in our study.The data from relevant papers were segregated into five groups according to the factor studied and type of study,and tables were created for a comparison of data.Results Temperature above the threshold of 43℃ was reached only when the power was>40 W and when there was adequate irrigation(at least 15–30 mL/min).Shorter lasing time divided by lithotripsy time or operator duty cycles less than 70%also resulted in a smaller temperature rise.Conclusion At least eight factors modify the thermal effects of lasers,and most importantly,the use of chilled irrigation at higher perfusion rates,lower power settings of<40 W,and with a shorter operator duty cycle will help to prevent thermal injuries from occurring.Stones impacted in the ureter or pelvi-ureteric junction further increase the probability of thermal injuries during laser firing. 展开更多
关键词 Stone disease Laser lithotripsy IRRIGATION Thermal effect Operator duty cycle
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Immunomodulatory effects and clinical application of exosomes derived from mesenchymal stem cells 被引量:1
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作者 Yang-Fei Yi Zi-Qi Fan +5 位作者 Can Liu Yi-Tong Ding Yao Chen Jie Wen Xiao-Hong Jian Yu-Fei Li 《World Journal of Stem Cells》 2025年第3期1-15,共15页
Exosomes(Exos)are extracellular vesicles secreted by cells and serve as crucial mediators of intercellular communication.They play a pivotal role in the pathogenesis and progression of various diseases and offer promi... Exosomes(Exos)are extracellular vesicles secreted by cells and serve as crucial mediators of intercellular communication.They play a pivotal role in the pathogenesis and progression of various diseases and offer promising avenues for therapeutic interventions.Exos derived from mesenchymal stem cells(MSCs)have significant immunomodulatory properties.They effectively regulate immune responses by modulating both innate and adaptive immunity.These Exos can inhibit excessive inflammatory responses and promote tissue repair.Moreover,they participate in antigen presentation,which is essential for activating immune responses.The cargo of these Exos,including ligands,proteins,and microRNAs,can suppress T cell activity or enhance the population of immunosuppressive cells to dampen the immune response.By inhibiting lymphocyte proliferation,acting on macrophages,and increasing the population of regulatory T cells,these Exos contribute to maintaining immune and metabolic homeostasis.Furthermore,they can activate immune-related signaling pathways or serve as vehicles to deliver microRNAs and other bioactive substances to target tumor cells,which holds potential for immunotherapy applications.Given the immense therapeutic potential of MSC-derived Exos,this review comprehensively explores their mechanisms of immune regulation and therapeutic applications in areas such as infection control,tumor suppression,and autoimmune disease management.This article aims to provide valuable insights into the mechanisms behind the actions of MSC-derived Exos,offering theoretical references for their future clinical utilization as cell-free drug preparations. 展开更多
关键词 Mesenchymal stem cells EXOSOMES Immunomodulatory effects Clinical application Therapeutic potential
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Late effects of the treatment of childhood cancer
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作者 Jelena Roganovic 《World Journal of Clinical Cases》 SCIE 2025年第7期6-12,共7页
Excellent progress has been made in the last few decades in the cure rates of pediatric malignancies,with more than 80%of children with cancer who have access to contemporary treatment being cured.However,the therapie... Excellent progress has been made in the last few decades in the cure rates of pediatric malignancies,with more than 80%of children with cancer who have access to contemporary treatment being cured.However,the therapies responsible for this survival can also produce adverse physical and psychological long-term outcomes,referred to as late effects,which appear months to years after the completion of cancer treatment.Research has shown that 60%to 90%of childhood cancer survivors(CCSs)develop one or more chronic health conditions,and 20%to 80%of survivors experience severe or life-threatening complications during adulthood.Therefore,understanding the late side effects of such treatments is important to improve the health and quality of life of the growing population of CCSs. 展开更多
关键词 SURVIVORSHIP CANCer CHILDREN TREATMENT Late effects
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基于非Fourier生物热传导解析解的激光辐照皮肤组织热损伤分析
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作者 张丽静 张齐 尚新春 《北京理工大学学报》 北大核心 2026年第2期192-201,共10页
较为准确地预测激光辐照下皮肤组织内部的热分布和热损伤是生物医学领域的一个难题.为探究这个问题,提出了一种使用Laplace和Hankel变换推导出解析解的策略.建立三维非Fourier热传导模型,并引入升温函数简化问题.通过积分变换及其逆变... 较为准确地预测激光辐照下皮肤组织内部的热分布和热损伤是生物医学领域的一个难题.为探究这个问题,提出了一种使用Laplace和Hankel变换推导出解析解的策略.建立三维非Fourier热传导模型,并引入升温函数简化问题.通过积分变换及其逆变换推导出解析解,并基于该解析解进行数值模拟,得到了不同辐照时间和半径下皮肤热分布和热损伤的预测结果,进而研究了激光辐照持续时间和半径对皮肤组织的影响.此外,对非Fourier热传导模型和经典Fourier热传导模型得到的皮肤组织热损伤预测结果进行了全面比较.分析结果表明,非Fourier和经典Fourier两种热传导模型所预测的热损伤深度是不同的.具体来讲,在短时间辐照时,非Fourier热传导理论的预测深度要小于Fourier热传导理论,而长时间辐照时,结果恰好相反. 展开更多
关键词 激光 生物材料 非Fourier效应 积分变换 解析解 热损伤
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