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Research on Secondary Metabolites from a Mangrove-Derived Fungus Penicillium janthinellum XLN32122 and Their Biological Activities
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作者 Shi Jueying Qiu Yikang +6 位作者 Lan Jing Xu Zhenyang Wang Yi Li Jiaxiang Luo Youping Huang Guolei Zheng Caijuan 《有机化学》 北大核心 2026年第2期678-683,共6页
new heterocyclic dipeptide with a highly functionalized 1,2-oxazadecaline core,named trichodermamide H(1),and three known analogues,along with three known polyketides,were isolated from the fermentation extract of the... new heterocyclic dipeptide with a highly functionalized 1,2-oxazadecaline core,named trichodermamide H(1),and three known analogues,along with three known polyketides,were isolated from the fermentation extract of the mangrovederived fungus Penicillium janthinellum XLN32122.The structure of 1 was elucidated on the basis of extensive 1D and 2D NMR spectra data analysis,HR-ESI-MS,electronic circular dichroism(ECD)calculations.Trichodermamide B(3)exhibited better inhibitory effect on nitric oxide(NO)production in lipopolysaccharide(LPS)induced RAW 264.7 cells with an IC_(50)value of(13.13±0.005)μmol/L than that of the positive control dexamethasone[IC_(50)=(136.84±1.33)μmol/L].Compound 3 exhibited antibacterial activity against methicillin-resistant Staphylococcus aureus(MRSA)with an IC_(50)value of 12.5μg/mL,while the positive control vancomycin showed an IC_(50)value of 1.563μg/mL. 展开更多
关键词 mangrove-derived fungi secondary metabolites anti-inflammatory activity antibacterial activity
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Co(Ⅱ) and Ni(Ⅱ) complexes of 3,3-diphenylpropionic acid and 2,2′-dipyridylamine: Structures and biological activities
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作者 FENG Jing WANG Renshu +1 位作者 WANG Hu LIU Hailong 《无机化学学报》 北大核心 2026年第3期617-631,共15页
Two Co(Ⅱ)and Ni(Ⅱ)complexes were synthesized by synergistic coordination of 3,3-diphenylpropionic acid(HDPA)and 2,2′-bipyridylamine(PAm).The structures of complexes[Co(DPA)_(2)(PAm)]·2H_(2)O(1)and[Ni(DPA)_(2)(... Two Co(Ⅱ)and Ni(Ⅱ)complexes were synthesized by synergistic coordination of 3,3-diphenylpropionic acid(HDPA)and 2,2′-bipyridylamine(PAm).The structures of complexes[Co(DPA)_(2)(PAm)]·2H_(2)O(1)and[Ni(DPA)_(2)(PAm)]·2H_(2)O(2)were determined by single-crystal X-ray diffraction,IR spectroscopy,and powder X-ray diffraction.Hirshfeld surface analysis provided quantitative insights into the intermolecular interactions within the complexes,while molecular docking studies elucidated their binding modes and affinities toward urease.Furthermore,the biological activities of both complexes were systematically evaluated through a range of assays,including DNA binding,urease inhibition,antibacterial activity,and in vitro cytotoxicity against cancer cells.Both complexes exhibited binding affinity for DNA and displayed notable urease inhibitory activity.Under in vitro conditions,both complexes showed appreciable cytotoxicity toward HepG2 cells with efficacy comparable to clinically used platinumbased anticancer agents.CCDC:2479943,1;2479944,2. 展开更多
关键词 crystal structure computational analysis urease inhibition antibacterial activity CYTOTOXICITY
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Comprehensive review of the pharmacological potential of Passiflora incarnata L.:neuropsychiatric,antioxidant,antimicrobial,and anticancer activities
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作者 Balasubramanian Deepika Koyeli Girigoswami 《Traditional Medicine Research》 2026年第4期11-26,共16页
Passiflora incarnata L.,commonly known as passionflower,is traditionally cultivated as an ornamental plant but has demonstrated diverse therapeutic potential.Its pharmacological effects are attributed to bioactive com... Passiflora incarnata L.,commonly known as passionflower,is traditionally cultivated as an ornamental plant but has demonstrated diverse therapeutic potential.Its pharmacological effects are attributed to bioactive compounds such as flavonoids and alkaloids,which influence multiple biological pathways.This review aims to summarise and critically analyse recent findings on the pharmacological properties of Passiflora incarnata L.,focusing on its neuropsychiatric,antioxidant,antimicrobial,and anticancer activities.A targeted literature search was conducted in PubMed,Scopus,Web of Science,and Google Scholar for peer-reviewed publications between 2000 to 2025.Relevant articles were screened,and a more appropriate article related to the objective of the review was selected.Some classical papers are also cited as per the requirement of the topic.Passiflora incarnata L.showed multifunctional medicinal properties with various applications in neuropsychiatry,oxidative stress management,antimicrobial agent,and as an anticancer agent.The U.S.Food and Drug Administration categorizes passionflower extracts as“generally recognized as safe”.However,most evidence remains preclinical,with methodological variation limiting generalisation.Standardised formulation,robust clinical trials,and in-depth in vivo studies are essential to establish its therapeutic relevance and safety in modern medicine. 展开更多
关键词 Passiflora incarnata L ANTI-DEPRESSANT antioxidant activity antimicrobial activity anti-anxiety activity anticancer activity
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Time-dependent ground stability of inclined backfilled stope characterized by creep behavior
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作者 Ruofan Wang Yujie Zhu +3 位作者 Lang Liu Mengbo Zhu Baoxu Yan Hao Cui 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期479-491,共13页
Backfill is routinely adopted as a ground support measure for underground mines.However,ground stability enhancement by backfill has received limited research attention.This is likely to be because of the conventional... Backfill is routinely adopted as a ground support measure for underground mines.However,ground stability enhancement by backfill has received limited research attention.This is likely to be because of the conventional assumption that the fill material exhibits a significantly lower stiffness than the host rocks.Significantly,a recent pioneering work revealed the time-dependent ground stability around a backfilled stope with vertical walls through numerical modeling.In practice,underground stopes typically exhibit a higher or lower degree of inclination.This alters the stress state in peripheral rocks and may induce severe instability and dilution,particularly in stope-hanging walls.Hence,it is imperative to analyze the time-dependent ground stability of inclined backfilled stopes for backfill structure design.Therefore,comprehensive numerical simulations were performed using FLAC3D to address this knowledge deficiency by incorporating a coupled analysis of the backfill consolidation behavior and long-term creep deformation in surrounding rocks.The ground stability was evaluated based on the confinement effectiveness,strength-stress ratio,stress path relative to the yield surface,and time-dependent stress redistribution in the rocks.A parametric study revealed that the inclination angle of the backfilled stope reduced the confinement effectiveness in the host rocks when the wall creep was minor.This exacerbated the rock mass sloughing potential.However,a backfilled stope with a shallower dip angle achieved superior ground stability enhancement when the creep deformation was substantial,by applying a more significant compression on the backfill and effectively mobilizing its passive support performance during consolidation.Additional simulations were conducted to analyze the effects of stope height and width,mine depth,mechanical properties of rocks,backfill compressibility,and filling gap on the time-dependent stress redistribution and stability around the inclined backfilled stope. 展开更多
关键词 inclined backfilled stope ground stability time-dependency creep CONSOLIDATION
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Time-dependent behavior of deep roadway surrounding rock considering damage induced by excavation and mining disturbances:Experiments,modeling,and simulation
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作者 Qingzhe Cui Rongbin Hou +4 位作者 Zhenhua Li Feng Du Xu Chen Boyang Zhang Lielie Li 《International Journal of Mining Science and Technology》 2026年第2期439-456,共18页
In deep coal mining,surrounding rock is subjected to both high in-situ stress and intense mining disturbances,leading to significant time-dependent behavior.Accurately capturing this behavior is essential for predicti... In deep coal mining,surrounding rock is subjected to both high in-situ stress and intense mining disturbances,leading to significant time-dependent behavior.Accurately capturing this behavior is essential for predicting long-term roadway stability,necessitating the development of a reliable constitutive creep model and numerical simulation approach.In this study,creep experiments were conducted on pre-damaged rock with varying initial damage levels to investigate the time-dependent mechanical properties.Based on the experimental results,an accelerated-creep criterion was proposed,and an elastic-viscoplastic creep damage model(EVPCD)was established that simultaneously considers the effects of time-dependent damage and instantaneous damage caused by stress disturbances on rock creep behavior.Subsequently,the effectiveness of the proposed creep model was verified using experimental data,and the secondary development of the EVPCD model was completed based on the FLAC3D platform.Following this,a long-term stability analysis method of deep surrounding rock that accounts for excavation-and mining-induced disturbances was proposed.Using the main roadway of Xutuan Coal Mine as a case study,numerical simulations were carried out to investigate the time-dependent deformation and failure characteristics of the surrounding rock following excavation and mining disturbance.Combined with on-site monitoring of the surrounding rock damage areas,the results indicate that the EVPCD outperforms the CVISC and Nishihara models in predicting the time-dependent behavior of deep surrounding rock. 展开更多
关键词 Initial damage time-dependent damage Creep model Numerical implementation Damage evolution
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Strain localization and time-dependent deformation in granodiorite characterized by distributed optical fiber sensing
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作者 Shuting Miao Arno Zang +3 位作者 Guido Blöcher Yinlin Ji Hannes Hofmann Pengzhi Pan 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期166-178,共13页
A multi-stage stress relaxation test was performed on a granodiorite sample to understand the deformation process prior to the macroscopic failure of brittle rocks,as well as the transient response during stress relax... A multi-stage stress relaxation test was performed on a granodiorite sample to understand the deformation process prior to the macroscopic failure of brittle rocks,as well as the transient response during stress relaxation.Distributed optical fiber sensing was used to measure strains across the sample surface by helically wrapping the single-mode fiber around the cylindrical sample.Close agreement was observed between the circumferential strains obtained from the optical fibers and the extensometer.The reconstructed full-field strain contours show strain heterogeneity from the crack closure phase,and the strains in the later deformation phase are dominantly localized within the former high-strain zone.The Gini coefficient was used to quantify the degree of strain localization and shows an initial increase during the crack closure phase,a decrease during the linear elastic phase,and a subsequent increase during the post-yielding phase.This behavior corresponds to a process of initial localization from an imperfect boundary condition,homogenization,and eventual relocalization prior to the macroscopic failure of the sample.The transient strain rate decay during the stress relaxation phase was quantified using the p-value in the“Omori-like"power law function.A higher initial stress at the onset of relaxation results in a lower p-value,indicating a slower strain rate decay.As the sample approaches macroscopic failure,the lowest p-value shifts from the most damaged zone to adjacent areas,suggesting stress redistribution or crack propagation in deformed crystalline rocks under stress relaxation conditions. 展开更多
关键词 Distributed optical fiber sensing Stress relaxation Strain localization time-dependent deformation
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In-situ stress solution theory for borehole overcoring technique incorporating time-dependent effect of stress relief and its applications
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作者 Daohong Xia Shengjun Miao +5 位作者 Lianjun Chen Yuan Li Zejing Liu Rongmin Zhang Pengjin Yang Pengcheng Li 《International Journal of Mining Science and Technology》 2026年第1期187-203,共17页
In-situ stress is a key parameter for underground mine design and rock stability analysis.The borehole overcoring technique is widely used for in-situ stress measurement,but the rheological recovery deformation of roc... In-situ stress is a key parameter for underground mine design and rock stability analysis.The borehole overcoring technique is widely used for in-situ stress measurement,but the rheological recovery deformation of rocks after stress relief introduces errors.To improve accuracy,this study proposes an in-situ stress solution theory that incorporates time-dependent stress relief effects.Triaxial stepwise loadingunloading rheological tests on granite and siltstone established quantitative relationships between instantaneous elastic recovery and viscoelastic recovery under different stress levels,confirming their impact on measurement accuracy.By integrating a dual-class elastic deformation recovery model,an improved in-situ stress solution theory was derived.Additionally,accounting for the nonlinear characteristics of rock masses,a determination method for time-dependent nonlinear mechanical parameters was proposed.Based on the CSIRO hollow inclusion strain cell,time-dependent strain correction equations and long-term confining pressure calibration equations were formulated.Finally,the proposed theory was successfully applied at one iron mine(736 m depth)in Xinjiang,China,and one coal mine(510 m depth)in Ningxia,China.Compared to classical theory,the calculated mean stress values showed accuracy improvements of 6.0%and 9.4%,respectively,validating the applicability and reliability of the proposed theory. 展开更多
关键词 In-situ stress solution theory Borehole overcoring technique time-dependent effect of stress relief Viscoelastic recovery strain of rock In-situ stress measurement
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Pharmacological activities of ruscogenin: A narrative review
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作者 Preeti D.Verma Sanskruti R.Rathod +3 位作者 Niyati J.Lad Keval D.Prajapati Arjunsinh A.Rathod Mamta B.Shah 《Asian Pacific Journal of Tropical Biomedicine》 2026年第2期51-58,共8页
Ruscogenin,a steroidal sapogenin,is primarily derived from the genus Ruscus.It demonstrates a wide range of pharmacological actions that hold substantial promise for therapeutic use.By conducting a comprehensive exami... Ruscogenin,a steroidal sapogenin,is primarily derived from the genus Ruscus.It demonstrates a wide range of pharmacological actions that hold substantial promise for therapeutic use.By conducting a comprehensive examination of electronic databases including PubMed,ScienceDirect,and SciFinder,we identified studies on ruscogenin to date.This review aims at emphasizing the findings related to the bioactivities of ruscogenin,particularly its protective activities in neurological and inflammatory disorders,hemorrhoids,and cancer.Ruscogenin has been demonstrated to possess anti-ulcer,anti-osteoporotic,and skin-lightening properties as a therapeutic agent.It has also been proven effective in managing metabolic disorders by reducing inflammation and improving lipid metabolism,particularly in conditions such as non-alcoholic steatohepatitis and diabetic nephropathy.Reports indicate that it can prevent acute lung injury by protecting pulmonary endothelial cells from apoptosis and modulating inflammatory cytokines.Additionally,ruscogenin promotes neurological recovery by mitigating oxidative stress.It also shows anti-cancer properties,leading to apoptosis and hindering metastasis,particularly in pancreatic and hepatocellular carcinoma.This review summarizes the potential medical applications of ruscogenin and underscores the need for further research on its mechanisms of action. 展开更多
关键词 Ruscogenin Steroidal sapogenin Ruscus aculeatus Pharmacological activity
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Chemical composition and biological activities of Panax notoginseng
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作者 Yu Wang Da Teng +4 位作者 Zixuan Che Ran Guo Meng Zhang Ying Li Yu Chen 《Asian Journal of Traditional Medicines》 2026年第1期31-41,共11页
Panax notoginseng(P.notoginseng),a valuable traditional Chinese medicine,is the dried root of plants in Acanthopanax gracilistylus family,with the effect of dispersing blood stasis,eliminating swelling and relieving p... Panax notoginseng(P.notoginseng),a valuable traditional Chinese medicine,is the dried root of plants in Acanthopanax gracilistylus family,with the effect of dispersing blood stasis,eliminating swelling and relieving pain.With the development of modern medicine,the active ingredients and mechanisms of P.notoginseng have been gradually revealed.The present paper systematically reviews the chemical composition and biological activities of P.nologinseng,to provide a scientific basis and reference for detailed research on P.nologinseng. 展开更多
关键词 Panax notoginseng chemical composition biological activity
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Atramacronins A-P,eudesmane-type sesquiterpenoid dimers from Atractylodes macrocephala with anti-hepatocellular carcinoma activities
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作者 Ganggang Zhou Xinru Li +10 位作者 Jiajia Liu Jiqiong Wang Zhaoyue Dong Ammara Khalid Yinda Qiu Zhihua Liao Guowei Wang Hui Liu Qingwen Zhang Min Chen Fancheng Meng 《Chinese Journal of Natural Medicines》 2026年第1期119-128,共10页
Atractylodes macrocephala Koidz.(A.macrocephala)is a medicinal and edible plant species belonging to the Compositae family.Its rhizome serves both therapeutic and nutritional purposes in China.This investigation led t... Atractylodes macrocephala Koidz.(A.macrocephala)is a medicinal and edible plant species belonging to the Compositae family.Its rhizome serves both therapeutic and nutritional purposes in China.This investigation led to the isolation of thirteen novel rearranged 9(8→7)-abeo-eudesmane-type sesquiterpenoid dimers(SDs),atramacronins A-M(1-13),three eudesmane-type SDs,atramacronins N-P(14-16),and two previously identified meroterpenoids,atrachinenin G(17)and atrachineninΙ(18),from Atractylodes macrocephala.Structure elucidation was accomplished through comprehensive spectroscopic analysis and single-crystal X-ray diffraction.Compounds 1,4-7,9,and 10 exhibited notable cytotoxicity against Hep3B,HepG2,and Huh7 cell lines,with half maximal inhibitory concentration(IC_(50))values ranging from 3.71 to 13.99μmol·L^(-1). 展开更多
关键词 Atractylodes macrocephala SESQUITERPENOID Cytotoxic activity Hepatocellular carcinoma
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When clothing learns to"think",temperature changes will no longer be a problem in outdoor activities
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作者 Xiao Ying Qiu Shuchen 《China Textile》 2026年第1期12-13,共2页
Lin Wei is a hiking enthusiast.At six o'clock on the last Saturday morning,the temperature at the foot of the mountain was only 2℃,so she put on her thickest fleece jacket.However,after only half an hour of climb... Lin Wei is a hiking enthusiast.At six o'clock on the last Saturday morning,the temperature at the foot of the mountain was only 2℃,so she put on her thickest fleece jacket.However,after only half an hour of climbing,the heat left her drenched in sweat,making her feel very cold.By midday,the temperature was approaching 20℃,and her heavy jacket had to be tied around her waist,becoming a burden during her hike.This outdoor adventure allowed her to appreciate the beautiful scenery,but also subjected her to repeated changes in temperature. 展开更多
关键词 HIKING temperature changes outdoor activities CLOTHING temperature regulation
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Phytochemical profile and biological activities of Plantago major L.:A comprehensive review
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作者 Aamna Majeed Zarfishan Zulfiqar +6 位作者 Zain Fatima Seerat Fatima Gulzar Muhammad Muhammad Wajid Rana Rashad Mahmood Khan Muhammad Mushtaq Adnan Ashraf 《Asian Pacific Journal of Tropical Biomedicine》 2026年第3期95-108,共14页
Plantago major L.,commonly known as plantain,waybread,or dooryard plantain,is a versatile medicinal plant with multiple therapeutic applications.Traditionally,various parts of the plant have been formulated into syrup... Plantago major L.,commonly known as plantain,waybread,or dooryard plantain,is a versatile medicinal plant with multiple therapeutic applications.Traditionally,various parts of the plant have been formulated into syrups,drops,ointments,vaginal suppositories,gargles,and roasted preparations to treat diverse ailments,such as liver disorders,earaches,epilepsy,asthma,stomachaches,diarrhea,constipation,polymenorrhea,and uterine disorders.The plant contains clinically valuable bioactive compounds,including polysaccharides,flavonoids,lipids,iridoid glycosides,caffeic acid derivatives,terpenoids,alkaloids,and organic acids.These bioactive constituents are the primary contributors to the plant’s broad spectrum of biological activities,including antioxidant,anti-inflammatory,antibacterial,antidiarrheal,hepatoprotective,antiviral,antiphage,antinociceptive,antiulcerogenic,antigenotoxic,and immunomodulatory effects of the plant.This review comprehensively summarizes the phytochemical composition,traditional medicinal applications,and biological properties of this multifunctional medicinal plant. 展开更多
关键词 Plantago major Anticancer activity ANTI-INFLAMMATORY Antibacterial ANTIDIARRHEAL HEPATOPROTECTIVE ANTIVIRAL ANTINOCICEPTIVE Antiulcerogenic Antigenotoxic IMMUNOMODULATORY
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New meroterpenoids featuring a rare 3/5/6/6/11/6/6 fused-ring skeleton from Penicillium brefeldianum SMU03 and their antifibrotic activities
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作者 Xia Cheng Lei Di +1 位作者 Luying Wu Qi Luo 《Chinese Journal of Natural Medicines》 2026年第1期112-118,共7页
Penicine A(1),a meroterpenoid featuring a novel 3/5/6/6/11/6/6 polycyclic backbone,together with two new metabolites,penicines B(2)and C(4),and six known compounds,were isolated from the mangrove rhizosphere soil-deri... Penicine A(1),a meroterpenoid featuring a novel 3/5/6/6/11/6/6 polycyclic backbone,together with two new metabolites,penicines B(2)and C(4),and six known compounds,were isolated from the mangrove rhizosphere soil-derived fungus Penicillium brefeldianum SMU03.The structures of these metabolites were elucidated through extensive spectroscopic analysis combined with quantum chemical calculations.Notably,1 exhibits a highly unusual molecular architecture,incorporating a dioxaspiro[4.5]decane motif and a rare bridgehead double bond(anti-Bredt system).A plausible biosynthetic pathway,involving sequential intermolecular[4+2]cycloaddition reactions,is proposed.Additionally,meroterpenoids 1 and 3 demonstrate significant antifibrotic activity in transforming growth factorβ1(TGF-β1)-induced human renal proximal tubular epithelial cells. 展开更多
关键词 Penicillium brefeldianum SMU03 Meroterpenoid Antifibrotic activity Plausible biosynthetic pathway
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Application of the DITAPH model coupling human activities and groundwater dynamics for nitrate vulnerability assessment:A case study in Quanzhou,China
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作者 Jian-feng Li Yuan-jing Zhang +4 位作者 Ya-ci Liu Qi-chen Hao Chun-lei Liu Sheng-wei Cao Zheng-hong Li 《Journal of Groundwater Science and Engineering》 2026年第1期32-48,共17页
To address the deficiencies in comprehensive surface contamination prevention strategies within China's nitrate-affected regions,this research innovatively proposes the DITAPH model-a systematic framework integrat... To address the deficiencies in comprehensive surface contamination prevention strategies within China's nitrate-affected regions,this research innovatively proposes the DITAPH model-a systematic framework integrating groundwater nitrate vulnerability assessment and Nitrate Vulnerable Zones(NVZs)delineation through optimization of hydrogeological parameters.Based on detailed hydrogeological and hydrochemical investigations,the DITAPH model was applied in the plain areas of Quanzhou to evaluate its applicability.The model selected hydrogeological parameters(depth of groundwater,lithology of the vadose zone,topographic slope,aquifer water yield property),one climatic parameter(precipitation),and two anthropogenic parameters(land use type and population density)as assessment indicators.The results of the groundwater nitrate vulnerability assessment showed that the low,relatively low,relatively high,and high groundwater nitrate vulnerability zones in the study area accounted for 5.96%,35.44%,53.74%and 4.86%of the total area,respectively.Groundwater nitrate vulnerability was most strongly influenced by human activities,followed by groundwater depth and topographic slope.The high vulnerability zone is mainly affected by domestic and industrial wastewater,whereas the relatively high groundwater nitrate vulnerability zone is primarily influenced by agricultural activities.Validation of the DITAPH model revealed a significant positive correlation between the DITAPH index(DI)and nitrate concentration(ρ(NO3−)).The results of the NVZs delineated by the DITAPH model are reliable and can serve as a tool for water resource management planning,guiding the development of targeted measures in the NVZs to prevent groundwater contamination. 展开更多
关键词 Nitrate contamination NVZs delineation Human activity coupling Pollution risk management
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Patterns,synergies,and interactions between human activities and living environment on the Qinghai-Xizang Plateau
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作者 GUO Changqing ZHANG Haiyan +2 位作者 DOU Yinyin KUANG Wenhui BAO Wenxuan 《Journal of Geographical Sciences》 2026年第2期341-362,共22页
Understanding the impacts of human activities on the plateau’s living environment is essential for advancing modernization pathways that promote harmony between humanity and nature.However,studies on the dynamic inte... Understanding the impacts of human activities on the plateau’s living environment is essential for advancing modernization pathways that promote harmony between humanity and nature.However,studies on the dynamic interactions between human activities and the living environment on the Qinghai-Xizang Plateau(QXP)remain limited,with a paucity of quantitative relationship analyses.This study established an assessment framework to evaluate human influences on the living environment in QXP,using data on typical human activities,ecological conditions,and human settlements.Within this framework,the spatial analysis methods and the coupling coordination model were used to examine the spatio-temporal characteristics and relationship of human activities and living environment on the QXP from 2000 to 2020.The geographical detector model was then applied to identify the key factors influencing the plateau’s human living environment.Subsequently,the four-quadrant analysis model was adopted to assess human influences on the living environment.The results indicate that the human activity intensity(HAI)on the QXP remained relatively low yet increased by 15.41%from 2000 to 2020.Spatially,the human living environment quality(LEQ)improved from northwest to southeast,with 61.14%of the areas remaining stable and 18.47%experiencing slight improvement.The analysis of coupling coordination revealed a continuous improvement between the HAI and LEQ,with the areas of high and relatively high coordinated types increasing by more than 9%.Precipitation and urban-rural construction were identified as the primary factors influencing changes in the LEQ.The interaction between the HAI and LEQ was strengthening,with 40.44%classified as coordinated development type and 38.35%as development-environment conflict type.These findings provide valuable insights for enhancing the resilience of human settlements and promoting green development across the plateau. 展开更多
关键词 human activities living environment spatio-temporal characteristics coupling coordination influencing factor Qinghai-Xizang Plateau
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Mapping interaction between human activities and land surface temperature in the Yellow River Basin
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作者 ZHANG Zhongwu BAI Xue +4 位作者 LI Zhe YUE Xin ZHANG Xin YANG Shuo WANG Lu 《Journal of Geographical Sciences》 2026年第1期79-106,共28页
Human activities have significantly impacted the land surface temperature(LST),endangering human health;however,the relationship between these two factors has not been adequately quantified.This study comprehensively ... Human activities have significantly impacted the land surface temperature(LST),endangering human health;however,the relationship between these two factors has not been adequately quantified.This study comprehensively constructs a Human Activity Intensity(HAI)index and employs the Maximal Information Coefficient,four-quadrant model,and XGBoostSHAP model to investigate the spatiotemporal relationship and influencing factors of HAI-LST in the Yellow River Basin(YRB)from 2000 to 2020.The results indicated that from 2000 to 2020,as HAI and LST increased,the static HAI-LST relationship in the YRB showed a positive correlation that continued to strengthen.This dynamic relationship exhibited conflicting development,with the proportion of coordinated to conflicting regions shifting from 1:4 to 1:2,indicating a reduction in conflict intensity.Notably,only the degree of conflict in the source area decreased significantly,whereas it intensified in the upper and lower reaches.The key factors influencing the HAI-LST relationship include fractional vegetation cover,slope,precipitation,and evapotranspiration,along with region-specific factors such as PM_(2.5),biodiversity,and elevation.Based on these findings,region-specific ecological management strategies have been proposed to mitigate conflict-prone areas and alleviate thermal stress,thereby providing important guidance for promoting harmonious development between humans and nature. 展开更多
关键词 Yellow River Basin human activities land surface temperature maximal information coefficient XGBoost-SHAP
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Stakeholder partnership in the development of standardization activities
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作者 Zaki Al-Rubaei 《China Standardization》 2026年第1期24-29,共6页
Introduction:The choice is no longer whether—but when and how!Today,organizations can no longer choose whether or not to engage with stakeholders;the only real decision is when and how to do it successfully.Engaging ... Introduction:The choice is no longer whether—but when and how!Today,organizations can no longer choose whether or not to engage with stakeholders;the only real decision is when and how to do it successfully.Engaging stakeholders is essential for any type of organization,public,private,or civil society.In fact,it is a fundamental part of effective governance,continuous improvement,and social responsibility.The principle behind stakeholder engagement is simple yet powerful:those who can influence or be affected by an organization's mission must be given the opportunity to express their views and contribute to shaping the decisions that impact them. 展开更多
关键词 standardization activities continuous improvement stakeholder engagement effective governancecontinuous social responsibility engage stakeholdersthe governance
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Unraveling the invasion patterns of Galinsoga quadriradiata in mountain ranges:Insights from human activities,phenotypic and genetic variations
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作者 Yu Chen Xingjiang Song +5 位作者 Gang Liu Jia Wang Chunling Zhang Xiaojian Chang Jiabin Zou Zhihong Zhu 《Plant Diversity》 2026年第1期192-203,共12页
Prevention of biological invasion requires understanding how alien species invade native communities.Although studies have identified mechanisms that underlie plant invasion in some habitats,limited attention has focu... Prevention of biological invasion requires understanding how alien species invade native communities.Although studies have identified mechanisms that underlie plant invasion in some habitats,limited attention has focused on invasion patterns along elevational gradients.In this study,we asked which factors drive the global and regional distribution of the invasive plant Galinsoga quadriradiata along elevational gradients.To answer this question,we examined whether human activities(i.e.,roads)promote G.quadriradiata invasion,how seed dispersal-related traits of G.quadriradiata change along elevation gradients,and whether G.quadriradiata has adapted to high-elevation environments through phenotypic plasticity or genetic variation.On the global scale,we found that human activities and road density positively contribute to the G.quadriradiata expansion in mountainous areas.Field surveys in China revealed significant elevational differences in the seed dispersal traits of G.quadriradiata,with higher-elevation populations exhibiting lower dispersal ability and generally lower genetic diversity.Under common conditions,high-elevation populations showed higher leaf mass ratio but lower root mass ratio and reproductive allocation.This suggests that high-elevation environments create a barrier to dispersal for G.quadriradiata,and that G.quadriradiata has adapted phenotypically to these conditions.Our study indicates that the elevational invasion pattern of G.quadriradiata is shaped by multiple factors,particularly human activities and phenotypic adaptability.In addition,our finding that G.quadriradiata invasion at high elevations is not constrained by low genetic diversity indicates that monitoring and management of G.quadriradiata in mountainous areas should be strengthened. 展开更多
关键词 Invasive plants Phenotypic plasticity Seed dispersal ability Genetic variation Human activities Elevational gradient
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Sterpiperazines A and B,steroid-indole alkaloids with Tdp1 inhibitory and chemotherapy sensitizing activities from marine fungus Aspergillus sp.EGF 15-0-3
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作者 Xia Wei Zheng-Wu Luo +6 位作者 Guo-Qiang Zhang Yan-An Lin Ze-Kun Zhang Lin-Kun An Xi-Xin He Jun-Cheng Su Cui-Xian Zhang 《Chinese Chemical Letters》 2026年第2期331-334,共4页
Hyperactivation of DNA repairing pathway is highly associated with the chemosensitivity and chemoresistance of cancer cells.In this manuscript,guided by cascaded one strain many compounds-global natural products socia... Hyperactivation of DNA repairing pathway is highly associated with the chemosensitivity and chemoresistance of cancer cells.In this manuscript,guided by cascaded one strain many compounds-global natural products social molecular networking(OSMAC-GNPS)strategy,a pair of epimeric environmental-induced metabolites were isolated from Aspergillus sp.EGF 15-0-3.Structurally,sterpiperazines A(1)and B(2)represent the first steroid-based indole alkaloids with unprecedented backbones.Biologically,compound 1 could be identified as a novel tyrosyl-DNA phosphodiesterase 1(Tdp1)inhibitor with a unique mechanism distinct from the reported modulators,and was able to significantly enhance the sensitivity of NCI-H460 cells to the clinic chemotherapeutic drug through inhibiting the DNA repairment and enhanced the DNA damage of cancer cells. 展开更多
关键词 Environmental-induced metabolites Steroid-based indole alkaloids Tdp1 inhibition Chemotherapy sensitizing activities Aspergillus sp.EGF 15-0-3
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A Cost-Effective Approach to Precisely Estimate Singlet-Triplet Energy Gaps in MR-TADF Molecules:Combining Delta Self-Consistent Field and Time-Dependent Density Functional Theory Methods
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作者 Qian Jina Dong Wang 《Chinese Journal of Chemical Physics》 2026年第1期41-50,I0021-I0032,I0042,共23页
As a novel class of purely organic fluores-cent materials,multiple resonance thermal-ly activated delayed fluorescence(MR-TADF)compounds hold significant promise for next-generation display technologies.The efficiency... As a novel class of purely organic fluores-cent materials,multiple resonance thermal-ly activated delayed fluorescence(MR-TADF)compounds hold significant promise for next-generation display technologies.The efficiency of exciton utilization and the overall performance of organic light-emit-ting devices are closely linked to the singlet-triplet energy gap(ΔE_(ST))of MR-TADF emitters.Identifying an economic and accu-rate theoretical approach to predictΔE_(ST)would be beneficial for high-throughput screening and facilitate the inverse design of MR-TADF molecules.In this study,we evaluated the S_(1)state energy(E(S_(1))),T_(1)state ener-gy(E(T_(1))),andΔE_(ST)using three different physical interpretations:adiabatic excitation ener-gy,vertical absorption energy,and vertical emission energy.We employed the time-depen-dent density functional theory(TDDFT)and delta self-consistent field(ΔSCF)methods to calculate E(S_(1)),E(T_(1)),andΔE_(ST)for 20 MR-TADF molecules reported in the literature.We compared these calculated values with experimental data obtained from fluorescence spec-troscopy at room-temperature(or 77 K)and phosphorescence spectroscopy conducted at 77 K.Our findings indicate that the vertical absorption energy at the S0 state minimum,deter-mined by theΔSCF method,accurately predicts the S_(1)state energy.Similarly,the vertical absorption energy at the S0 state minimum,calculated using the TDDFT method,effectively predicts the T_(1)state energy.TheΔE_(ST)derived from the difference between these two excita-tion energies exhibited the smallest mean absolute error of only 0.039 eV compared to the ex-perimental values.This combination represents the most accurate and cost-effective method reported to date for predicting theΔE_(ST)of MR-TADF molecules,and can be integrated into AI-driven inverse design workflows for new emitters. 展开更多
关键词 Organic light-emitting diode Multiple resonance thermally activated delayed fluorescence emitter Single-triplet energy gap Delta self-consistent field method Time-de-pendent density functional theory method
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