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Modelling Regional Land Change Scenarios to Assess Land Abandonment and Reforestation Dynamics in the Pyrenees(France) 被引量:3
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作者 Laure A.VACQUIE Thomas HOUET +2 位作者 Terry L.SOHL Ryan REKER Kristi L.SAYLER 《Journal of Mountain Science》 SCIE CSCD 2015年第4期905-920,共16页
Over the last decades and centuries,European mountain landscapes have experienced substantial transformations.Natural and anthropogenic LULC changes(land use and land cover changes), especially agro-pastoral activitie... Over the last decades and centuries,European mountain landscapes have experienced substantial transformations.Natural and anthropogenic LULC changes(land use and land cover changes), especially agro-pastoral activities,have directly influenced the spatial organization and composition of European mountain landscapes.For the past sixty years, natural reforestation has been occurring due to a decline in both agricultural production activities and rural population.Stakeholders, to better anticipate future changes,need spatially and temporally explicit models to identify areas at risk of land change and possible abandonment.This paper presents an integrated approach combining forecasting scenarios and a LULC changes simulation model to assess where LULC changes may occur in the Pyrenees Mountains,based on historical LULC trends and a range of future socio-economic drivers.The proposed methodologyconsiders local specificities of the Pyrenean valleys,sub-regional climate and topographical properties,and regional economic policies.Results indicate that some regions are projected to face strong abandonment, regardless of the scenario conditions.Overall, high rates of change are associated with administrative regions where land productivity is highly dependent on socio-economic drivers and climatic and environmental conditions limit intensive(agricultural and/or pastoral) production and profitability.The combination of the results for the four scenarios allows assessments of where encroachment(e.g.colonization by shrublands) and reforestation are the most probable.This assessment intends to provide insight into the potential future development of the Pyrenees to help identify areas that are the most sensitive to change and to guide decision makers to help their management decisions. 展开更多
关键词 pyrenees Land use change Land cover change Land abandonment Mountain landscapeReforestation LULC Model
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Frozen ground and periglacial processes relationship in temperate high mountains: a case study at Monte Perdido-Tucarroya area(The Pyrenees, Spain) 被引量:1
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作者 SERRANO Enrique LóPEZ-MORENO Juan Ignacio +4 位作者 GóMEZ-LENDE Manuel PISABARRO Alfonso MARTíN-MORENO Raúl RICO Ibai ALONSO-GONZáLEZ Esteban 《Journal of Mountain Science》 SCIE CSCD 2020年第5期1013-1031,共19页
Seasonally frozen ground,mountain permafrost and cryogenic geomorphological processes are important components of the Pyrenean high mountains.This work presents the results of a study on the distribution of frozen gro... Seasonally frozen ground,mountain permafrost and cryogenic geomorphological processes are important components of the Pyrenean high mountains.This work presents the results of a study on the distribution of frozen ground in a marginal and paraglacial environment of temperate mountains.An inventory was made of landforms and indicators of frozen ground,and frozen ground was mapped accordingly.During 2014 and 2016 ground temperatures and thermal regimes were monitored,basal temperatures of snow-cover(BTS)were measured and a thermal map was drawn.Differential thermal behaviours were detected among different elevations and slope orientations.Periglacial processes are the most widespread,in which frost weathering and nivation,together with gelifluction and cryoturbation,are the most efficient processes;the latter two are generally linked to the presence of frozen ground.The fall in air and ground temperatures with altitude,slope orientations,and snowpack thickness and evolution determine ground thermal regimes.In the study area,three types of thermal regimes were established:climate-controlled,snowcover-controlled,and frozen ground-controlled.Seasonally frozen ground occurs across a broad range of elevation between 2650 and 3075 m asl,whereas possible permafrost only occurs above 2750 m asl. 展开更多
关键词 GEOMORPHOLOGY PERIGLACIAL Seasonally frozen ground Mountain permafrost pyrenees
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Influence of Livestock Soil Eutrophication on Floral Composition in the Pyrenees Mountains 被引量:1
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作者 BADíA David MARTí Clara +3 位作者 SáNCHEZ José Ramón FILLAT Federico AGUIRRE Javier GóMEZ Daniel 《Journal of Mountain Science》 SCIE CSCD 2008年第1期63-72,共10页
Livestock behaviour in the Pyrenees includes free grazing and a long resting period that provokes the accumulation of dung and urine in some places,so-called camping areas. The aims of this study were (i) to analyze a... Livestock behaviour in the Pyrenees includes free grazing and a long resting period that provokes the accumulation of dung and urine in some places,so-called camping areas. The aims of this study were (i) to analyze any change in floral composition,and in nutritional and chemical contents of plants in a livestock camping area; and (ii) to relate the floral composition with soil chemical properties. In a linear transect,five sampling zones were established,from the centre of the camping area to the surrounding Nardus stricta-dominant pasture. The above ground plant biomass and the topsoil were sampled in each zone with 6 replicates per zone. Plant species were classified and weighed to calculate above ground biomass,nutritional and chemical contents,and Shannon diversity and evenness indices. Additionally,soils were sampled in two periods,at the beginning and at the end of grazing period. Soil available nutrients (nitrate,ammonium,phosphorus,potassium,calcium and magnesium),total nitrogen,organic carbon and pH were measured. Plant chemical contents (protein,lignin and others) were significantly related to the proportions of grasses,legumes and other plants; so,the protein content is positively correlated with legumes plant biomass while lignin content is negatively correlated with grasses. Both plant and soil nutrients increased linearly towards the centre of the camping area. However,the relationship among plant species richness,diversity and evenness relative to its position along the studied transect was bell-shaped. From the outskirts to the centre of the camping area,plants with low nutrient demand were progressively replaced by those with medium and high nutrients demand and by pioneers. Nardus stricta-dominant pasture has low plant diversity and plant nutrient content as well as a poor soil nutrient availability. The presence of the camping area introduced patches with more soil nutrients and new species in the large spatial scale. However at a small spatial scale,the strong soil nutrient concentration into the centre of the camping area reduced floral composition again. To ensure positive effects of camping areas on plant diversity,and to manage more effectively the nutrients returned to the soil,a reduction in the stocking rate should be pursued. 展开更多
关键词 Plant diversity species richness soil chemistry European mountains pyrenees
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Spatial distribution of morphometric parameters of glacial cirques in the Central Pyrenees(Aran and Boí valleys) 被引量:1
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作者 Luis LOPES Marc OLIVA +3 位作者 Marcelo FERNANDES Paulo PEREIRA Pedro PALMA Jesús RUIZ-FERNáNDEZ 《Journal of Mountain Science》 SCIE CSCD 2018年第10期2103-2119,共17页
Glacial cirques are typical landscape features of mid-latitude mountain environments like the Central Pyrenees. Their morphology as well as their spatial distribution provides insights about past glaciers and climates... Glacial cirques are typical landscape features of mid-latitude mountain environments like the Central Pyrenees. Their morphology as well as their spatial distribution provides insights about past glaciers and climates. In this study, we examine the distribution, morphometrical and topographical characteristics of glacial cirques in two U-shaped glacial valleys located in the Central Pyrenees – the Aran and the Boí valleys. They are located in different aspects of this mountain range(north vs south) under different climatic influences that promoted distinct glaciation patterns during the late Pleistocene. The spatial mapping of these landforms was carried out using high-resolution imagery and field observations. We analysed the data of the morphometrical and topographical variables of the glacial cirques by using different statistical and geospatial methods in order tounveil the factors controlling their formation and development. A total of 186 glacial cirques were mapped in the study area, including 119 in the Aran and 67 in the Boí valleys. The local topography and microclimate conditions lead to substantial differences in both areas in terms of the morphology and dimensions of the cirques. Glacial cirques in Boí are distributed at slightly higher elevations than in Aran and they are also larger, though their dimensions decrease with elevation in both valleys. Aran cirques are mostly oriented NE, while Boí landforms do not show any prevailing aspect. Even though lithology does not control the distribution of the glacial cirques, some specific lithological settings may favour the development of larger cirques. In general, glacial cirques in the Aran and the Boí valleys show morphometrical properties similar to those reported in other mid-latitude mountain ranges. 展开更多
关键词 Central pyrenees Aran and Boi valleys glacial cirques topography morphometry.
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Distribution and space use of seed-dispersing rodents in central Pyrenees:implications for genetic diversity,conservation and plant recruitment
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作者 Jon URGOITI Alberto MUÑOZ +1 位作者 Josep Maria ESPELTA Raúl BONAL 《Integrative Zoology》 SCIE CSCD 2018年第3期307-318,共12页
The function and conservation of many forest ecosystems depend on the distribution and diversity of the community of rodents that consume and disperse seeds.The habitat preferences and interactions are especially rele... The function and conservation of many forest ecosystems depend on the distribution and diversity of the community of rodents that consume and disperse seeds.The habitat preferences and interactions are especially relevant in alpine systems where such granivorous rodents reach the southernmost limit of their distribution and are especially sensitive to global warming.We analyzed the community of granivorous rodents in the Pyrenees,one of the southernmost mountain ranges of Europe.Rodent species were identified by DNA with particular attention to the Apodemus species,which are prominent seed-dispersing rodents in Europe.We confirmed for the first time the presence of the yellow-necked mouse,Apodemus flavicollis,in central Pyrenees,a typical Eurosiberian species that reaches its southernmost distribution limit in this area.We also found the wood mouse,Apodemus sylvaticus,a related species more tolerant to Mediterranean environments.Both rodents were spatially segregated by altitude.A.sylvaticus was rare at high altitudes,which might cause the genetic differentiation between populations of the different valleys reported here.We also found other seed consumers like dormice,Elyomis quercinus,and voles,Myodes glareolus,with marked habitat preferences.We suggest that population isolation among valleys may increase the genetic diversity of rodents,like A.sylvaticus.We also highlight the potential threat that global warming may represent for species linked to high-altitude refuges at the southern edge of its distribution,like Apodemus flavicollis.Finally,we discuss how this threat may have a dimension in the conservation of alpine forests dispersed by these rodent populations. 展开更多
关键词 DNA analysis pyrenees RODENTS seed dispersal vegetation structure
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Effect of snow on mountain river regimes: an example from the Pyrenees
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作者 Alba SANMIGUEL-VALLELADO Enrique MORAN-TEJEDA +1 位作者 Esteban ALONSO-GONZALEZ Juan Ignacio LOPEZ-MORENO 《Frontiers of Earth Science》 SCIE CAS CSCD 2017年第3期515-530,共16页
The purpose of this study was to characterize mountain river regimes in the Spanish Pyrenees and to assess the importance of snow accumulation and snowmelt on the timing of river flows. Daily streamflow data from 9 ga... The purpose of this study was to characterize mountain river regimes in the Spanish Pyrenees and to assess the importance of snow accumulation and snowmelt on the timing of river flows. Daily streamflow data from 9 gauging stations in the Pyrenees were used to characterize river regimes. These data were analyzed by hydrological indices, with a focus on periods when snow accumulation and snowmelt occurred. These results were combined with data on Snow Water Equivalent (SWE) (from measure- ments of depth and density of snow in the main river basins and also simulated by a process-based hydrological model), snowmelting (simulated by a process-based hydrological model), precipitation (from observations), and temperature (from observations). Longitude. and elevation gradients in the Pyrenees explain the transition of river regimes from those that mostly had low nival signals (in the west and at low elevations) to those that mostly had high nival signals (low winter runoff and late spring peakflow, in the east and at high elevations). Although trend analyses indicated no statistically signifi- cant changes, there was a trend of decreased nival signal over time in most of the analyzed rivers. Our results also demonstrated that snow processes cannot explain all of the interannual variability of river regimes, because the temporal distribution of liquid precipitation and tempera- ture play key roles in hydrography. 展开更多
关键词 river regime PRECIPITATION snow indices Spanish pyrenees streamflow
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Transcriptomic and biochemical analysis of the mechanism of sodium gluconate promoting the degradation of benzo [a] pyrene by Bacillus subtilis MSC4 被引量:1
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作者 Rui Chen Tangbing Cui 《Journal of Environmental Sciences》 2025年第6期39-53,共15页
Benzo[a]pyrene(B[a]P)is a carcinogenic environmental pollutant widely present in the environment and can enter the human body through the food chain.It is therefore essential to treat and remediate the B[a]P-contamina... Benzo[a]pyrene(B[a]P)is a carcinogenic environmental pollutant widely present in the environment and can enter the human body through the food chain.It is therefore essential to treat and remediate the B[a]P-contaminated environment.Microbial remediation of B[a]Pcontaminated environments is considered to be one of the most effective strategies,and the addition of biostimulants is a feasible method to further improve the effectiveness of microbial remediation.In this study,we used Bacillus subtilis MSC4 to screen for the stimulation of sodium gluconate,which promoted B[a]P degradation.Based on biochemical and transcriptomic analyses,Sodium gluconate was found to significantly increase the biomass of MSC4 and the expression of most genes involved in B[a]P degradation.Activities of central carbon metabolism,fatty acidβ-oxidation and oxidative phosphorylation were all promoted.The significant increase in acid-induced oxalate decarboxylase expression indicates a decrease in intracellular pH,which promoted the synthesis of acetoin and lactate.Genes involved in the nitrogen cycle,especially nitrification and denitrification,were significantly up-regulated,contributing to B[a]P degradation.Genes involved in the synthesis of enzyme cofactors,including thiamine,molybdenum cofactors,NAD and heme,were up-regulated,which contributes to increasing enzyme activity in metabolic pathways.Up-regulation of genes in flagella assembly,chemotaxis,and lipopeptide synthesis is beneficial for the dissolution and uptake of B[a]P.Genes related to the sugar transport system were upregulated,which facilitates the transport and absorption of monosaccharides and oligosaccharides by MSC4.This study provides a theoretical basis for the further application of sodium gluconate in the treatment of PAH-contaminated sites. 展开更多
关键词 TRANSCRIPTOMIC BIODEGRADATION BENZO[A]PYRENE Bacillus subtilis Sodium gluconate
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Coordination polymers based on anthracene-and pyrene-derived ligands:Crystal structure,fluorescent property,and framework isomerization
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作者 HU Youbo LI Donggang +2 位作者 SUN Changhua LU Zhenzhong GU Songjun 《无机化学学报》 北大核心 2025年第8期1681-1688,共8页
Six coordination polymers based on 9,10-di(pyridine-4-yl)-anthracene(DPA)and 1,6-di(1H-imidazol-1-yl)pyrene(DIP)were obtained by solvothermal reactions.{[Zn(DPA)Cl_(2)]·DMF·2H_(2)O}n(1)and{[Zn_(1.5)(DPA)_(1.... Six coordination polymers based on 9,10-di(pyridine-4-yl)-anthracene(DPA)and 1,6-di(1H-imidazol-1-yl)pyrene(DIP)were obtained by solvothermal reactions.{[Zn(DPA)Cl_(2)]·DMF·2H_(2)O}n(1)and{[Zn_(1.5)(DPA)_(1.5)Cl_(3)]·5H_(2)O}n(2)are framework isomers,which both contain zigzag chains formed by DPA,Zn^(2+),and Cl-.The zigzag chains in 1 are further assembled by C—H…Cl interactions into layers,and these layers exhibit two different orientations,displaying a rare 2D to 3D interpenetration mode.The zigzag chains in 2 are parallelly arranged.{[Zn_(3)(DPA)_(3)Br_(6)]·2DMF·_(1.5)H_(2)O}n(3)is isostructural to 2.3 was obtained using ZnBr_(2)instead of ZnCl_(2).[M(DPA)(formate)_(2)(H_(2)O)_(2)]n[M=Co(4),Cu(5)]are isostructural,contain chain structures formed by DPA,Cu^(2+)/Co^(2+),and for-mate ions,which were formed in situ in the solvothermal reaction.{[Zn(DIP)_(2)Cl]ClO_(4)}n(6)contains a layer structure formed by DIP and Zn^(2+).Free DPA and DIP ligands exhibited high fluorescence at room temperature,and coordina-tion polymers 3 and 6 displayed enhanced fluorescent emissions. 展开更多
关键词 coordination polymer anthracene derivatives pyrene derivatives fluorescence framework isomerization
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Fluorescent coordination polymers based on anthracene-and pyrene-derivative ligands
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作者 XI Jiming TENG Yukang +1 位作者 ZHANG Rui LU Zhenzhong 《无机化学学报》 北大核心 2025年第5期847-854,共8页
We report five coordination polymers(CPs)based on fluorescent ligands[1,6-di(1H-imidazol-1-yl)pyrene(dip),9,10-di(1H-imidazol-1-yl)anthracene(dia)]and anionic ligands[cyclohexane-1,4-dicarboxylic acid(H_(2)cda),campho... We report five coordination polymers(CPs)based on fluorescent ligands[1,6-di(1H-imidazol-1-yl)pyrene(dip),9,10-di(1H-imidazol-1-yl)anthracene(dia)]and anionic ligands[cyclohexane-1,4-dicarboxylic acid(H_(2)cda),camphoric acid(H_(2)cpa)].In[Cd(dip)(cda)]·4H_(2)O}_(n)(1),the Cd^(2+)ions,acting as tetrahedral nodes,are linked by dipand cda^(2-)ligands with four Cd^(2+)ions into five-fold interpenetrating network array of topology of dia.In{[Cd(dip)(cpa)]·4H_(2)O}_(n)(2),the Cd^(2+)ions,acting as a 4-connector,are linked by cpa^(2-)and dip ligands into a 3D framework ofcds topology.In{[Ni(dia)_(2)Cl_(2)]·DMF}_(n)(3),the Ni^(2+)ion is linked by four dia ligands into a layer structure,and 1Dchannels of a cross-section of 1.35 nm×0.96 nm are formed.In{[Cd(dia)_(2)(H_(2)O)_(2)](NO_(3))_(2)·2DMSO}n(4),the dia ligandsconnected Cd^(2+)ions into a 2D layer,and 1D channels are formed between adjacent layers with a cross-section of0.87 nm×0.43 nm.In[Zn(dip)Cl_(2)]_(n)(5),the Zn^(2+)ion is linked by dip ligands into an infinite 1D chain.The infrared,thermal gravimetric,and fluorescent emission data were collected and analyzed for these coordination polymers.CCDC:2356055,1;2440075,2;2356057,3;2356057,4;2356059,5. 展开更多
关键词 coordination polymer anthracene derivatives pyrene derivatives FLUORESCENCE
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Immunosuppressive role of benzo[a]pyrene exposure in prostate cancer progression
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作者 Zhijin Zhang Wentao Zhang +15 位作者 Huan Wang Haotian Chen Hong Wang Yang Yu Danjing Shen Man Pi Yang Wu Ming Luo Yanyan He Shiyu Mao Jiang Geng Wei Li Guangchun Wang Changcheng Guo Daqiang Yin Xudong Yao 《Journal of Environmental Sciences》 2025年第10期185-199,共15页
Epidemiological studies indicate that prostate cancer(PCa)is the second prevalent malignant tumor affecting men globally.Environmental pollution such as cigarette smoke is one of the important risk factors for the dev... Epidemiological studies indicate that prostate cancer(PCa)is the second prevalent malignant tumor affecting men globally.Environmental pollution such as cigarette smoke is one of the important risk factors for the development of prostate cancer.However,as one of the main carcinogens in cigarette smoke,the role of benzo[a]pyrene(BaP)in prostate cancer is still unclear.The current study aimed to investgate the impacts of BaP exposure on the progression of PCa towardmalignancy and the regulation of the immune microenvironment.We verified that BaP exposure can promote the proliferation,migration,and apoptosis of prostate cancer cells through in vitro experiments.We constructed a subcutaneous xenograft tumor model of BaP exposure mouse and found that can promote the proliferation of tumors in vivo.Organoids-driven by PCa patients showed higher growth rate under BaP exposure.Flow cytometric analysis demonstrated a remarkable decrease in CD4^(+)T and CD8^(+)T cell infiltration levels.Moreover,we identified four genes(Mdm2,Ar,Foxo1,Crebbp)were strongly associated with BaP exposure by combining mouse tumor RNA-seq and CTD database.Additionally,a nomogram integrating clinicopathological features was constructed to assess the prognosis of prostate cancer patients under BaP exposure.This study systematically proved that BaP exposure promotes malignant progression of PCa and suppresses the immune microenvironment,in which Mdm2,Ar,Foxo1,Crebbp may play a crucial role in inhibiting apoptosis.These findings offer novel insights into themechanisms via which BaP exposure contributes to PCa development. 展开更多
关键词 BENZO[A]PYRENE Prostate cancer Immune microenvironment ORGANOIDS
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The control technology of harmful substances impacting the quality of peanut oil:A review
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作者 Zifu Ni Xiao Ouyang +4 位作者 Azhen Nie Lina Huang Ruoqi Li Jinling Li Peng Chen 《Grain & Oil Science and Technology》 2025年第2期137-146,共10页
Peanut is a globally important leguminous crop and one of the most important oil crops.In response to the growing demand for high-quality peanut oil,advancements in processing technologies have led to significant impr... Peanut is a globally important leguminous crop and one of the most important oil crops.In response to the growing demand for high-quality peanut oil,advancements in processing technologies have led to significant improvements in oil quality.However,ensuring consistent quality remains a complex and ongoing challenge due to the multifaceted factors influencing peanut oil’s properties.This review synthesizes key scientific studies addressing these factors and explores the associated risks to oil quality and safety.Special attention is given to harmful contaminants such as aflatoxin B1(AFB1),3-chloro-1,2-propanediol esters(3-MCPDE),Benzo[a]pyrene(BaP),and trans-fatty acids(TFAs),which pose significant health risks and quality concerns.The review critically examines current detection methods for these contaminants and evaluates innovative removal strategies,such as biodegradation,physical refining,chemical treatments,and advanced adsorption techniques.Moreover,insights into the effects of raw material quality,processing conditions,and storage on oil quality were discussed.In conclusion,the review underscores the importance of adopting integrated approaches to control harmful substances while optimizing processing parameters to enhance peanut oil quality.These findings aim to guide researchers and industry practitioners in improving production practices,minimizing health risks,and providing safer and higher-quality peanut oil products for consumers. 展开更多
关键词 Peanut oil Aflatoxin B1 BENZO[A]PYRENE 3-chloro-1 2-propanediol esters Trans-fatty acids Safety
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The toxic impacts of microplastics-borne benzo[a]pyrene and heavy metals on the health and behavior of seahorse Hippocampus erectus
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作者 Ying LIU Nan LI +3 位作者 Dongwei SHANG Yanjing YANG Pei CUI Jinhui SUN 《Journal of Oceanology and Limnology》 2025年第2期559-571,共13页
Marine pollution poses a critical threat to biodiversity.The synergistic effects of microplastics,specifically high-density polyethylene(HDPE),combined with benzo[a]pyrene(B[a]P)and heavy metals,on the physiology and ... Marine pollution poses a critical threat to biodiversity.The synergistic effects of microplastics,specifically high-density polyethylene(HDPE),combined with benzo[a]pyrene(B[a]P)and heavy metals,on the physiology and feeding behavior of the seahorse,Hippocampus erectus were studied.The growth parameters,pollutant bioaccumulation,enzymatic response,and feeding dynamics were extensively analyzed.Seahorses exposed to microplastics-borne B[a]P and heavy metals exhibited notable reductions in body length and weight,as well as in survival rates,indicating severe stress from these contaminants.The accumulation of pollutant particularly B[a]P in seahorse exceeded China’s national regulatory limit of 5μg/kg,and the B[a]P accumulation in seahorses was obviously aided by HDPE microplastics,posing a risk to marine organisms and human health via the food chain.The adaptive response of the seahorses was evident shown in the elevation of antioxidant enzyme activities,which is a biological mechanism to mitigate oxidative stress induced by the pollutants.However,this physiological adaptation comes at a cost,as evidenced by marked changes in the feeding behavior.Results show that the efficiency and frequency of feeding were greatly reduced,indicating a heavy impact on the ecological role and survival of this marine creature in polluted habitats.This research offers a crucial perspective on the compound threats of microplastics and associated pollutants in marine ecosystems.It highlights the urgent need develop comprehensive strategies to address these environmental issues.The findings are an important contribution to ecotoxicology,providing a deeper understanding of how microplastics act as vectors for other contaminants and their profound effects on marine life,especially species like seahorses.This study calls for action to strengthen environmental policies and practices aimed at mitigating the impact of marine pollution. 展开更多
关键词 microplastics(MP) heavy metal benzo[a]pyrene(B[a]P) SEAHORSE synergistic effect
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Integrative insights into benzo[a]pyrene degradation mechanisms by Aspergillus fumigatus Z5:Spectroscopic,transcriptomic,and computational biological analyses
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作者 Guangming Zhang Yong Yang +7 位作者 Miao Dou Jie Pan Jialu Du Zhen Zhang Ning Mao Lingtao Luo Shiwei Wang Yanmei Sun 《Journal of Environmental Sciences》 2025年第11期866-878,共13页
High molecular weight polycyclic aromatic hydrocarbons(HMW-PAHs)pose significant environmental challenges due to their complex structures and persistent toxicity,and are difficult to be degraded by bacteria.Fungi,howe... High molecular weight polycyclic aromatic hydrocarbons(HMW-PAHs)pose significant environmental challenges due to their complex structures and persistent toxicity,and are difficult to be degraded by bacteria.Fungi,however,possess the ability to overcome these challenges,primarily through various enzymes with broad substrate specificity,including cytochrome P450(CYP450),laccase,manganese peroxidase,lignin peroxidase.As a result,the development of efficient fungal strains capable of degrading HMW-PAHs is essential for advancing bioremediation strategies.In this study,Aspergillus fumigatus Z5 was isolated from a contaminated site and demonstrated a remarkable ability to degrade the highly recalcitrant benzo[a]pyrene,achieving a degradation rate of 75.43%.Transcriptomic analysis revealed significant upregulation of 34 CYP450 genes.Among these genes,CYP3A4(gene 8840)showed strong binding affinity for benzo[a]pyrene,as confirmed by molecular docking studies,indicating its key role in the biodegradable process.Furthermore,the metabolic network analysis showed that the electron transfer required for CYP450-mediated oxidative reactions enhanced mitochondrial oxidative phosphorylation and subsequently energy metabolism in A.fumigatus Z5.This metabolic coordination likely facilitates the complete degradation of benzo[a]pyrene.Our study illuminates the fundamental roles of CYP450 from A.fumigatus Z5 in benzo[a]pyrene degradation and provides novel insight into designing and implementing enhanced bioremediation strategies. 展开更多
关键词 Cytochrome P450 enzymes Benzo[a]pyrene degradation Fungi High molecular weight polycyclic aromatic hydrocarbons(HMW-PAHs) TRANSCRIPTOMICS
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测定食品中苯并[a]芘的气相色谱—质谱法研究 被引量:3
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作者 王力清 黎军 《食品与机械》 CSCD 北大核心 2005年第4期44-46,共3页
研究了用气相色谱—质谱法测定食品中的苯并[a]芘的含量,该方法与荧光分光光度法比较具有可操作性强、准确度高和避免实验人员长时间受紫外线的照射等特点,可以定量测定苯并[a]芘的含量。并对特性基本相同的各种样品进行了加标回收检验... 研究了用气相色谱—质谱法测定食品中的苯并[a]芘的含量,该方法与荧光分光光度法比较具有可操作性强、准确度高和避免实验人员长时间受紫外线的照射等特点,可以定量测定苯并[a]芘的含量。并对特性基本相同的各种样品进行了加标回收检验,其回收率在85%以上,相关系数>0.9980,RSD<6.5%。 展开更多
关键词 气相色谱(GC) 质谱(MS) 苯并[a]芘[BenZ(a) pyrene] 荧光分光光度法 苯并[A]芘 定量测定 气相色谱 质谱法 食品
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通过探针分子芘研究超临界CO2流体密度不均一性 被引量:1
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作者 陈家玮 沈东 《地学前缘》 EI CAS CSCD 北大核心 2008年第4期125-131,共7页
近年来超临界CO2在环境地球科学领域应用广泛,在这些研究应用中,CO2流体在超临界状态下的溶剂化特性起到了十分重要的作用。在超临界高密度压缩区域里,体系温度和压力的稍许变化都会导致流体密度的突变,因此通过有效的探针分子研究超临... 近年来超临界CO2在环境地球科学领域应用广泛,在这些研究应用中,CO2流体在超临界状态下的溶剂化特性起到了十分重要的作用。在超临界高密度压缩区域里,体系温度和压力的稍许变化都会导致流体密度的突变,因此通过有效的探针分子研究超临界CO2流体的异常溶剂化行为具有重要的理论和应用价值。文中从新的角度运用荧光探针分子芘在温度308.15K和不同压力下研究超临界CO2性质,与以往采用的参照线方法有所不同,文中所提出的参照点模型手段引入序参量方法和新定义的溶剂化作用参量,测定近临界区超临界CO2流体局域密度增强的变化。文中同时讨论了3段密度区域模型(three-density regionmodel)、局域密度不均一性以及探针芘在超临界CO2中的分子间相互作用。将荧光探针分子研究的流体局域密度增强与热力学测试的流体等温压缩系数进行综合对比,有助于更好地从微观和宏观两方面理解超临界CO2的特性。 展开更多
关键词 超临界CO2 不均一性 芘(pyrene) 局域密度
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Pyrene分子(小片石墨晶体)的电子传导特性(英文)
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作者 王利光 张鸿宇 +4 位作者 陈蕾 李勇 郁鼎文 田上胜规 塚田捷 《人工晶体学报》 EI CAS CSCD 北大核心 2007年第5期1026-1030,1021,共6页
利用量子理论中基于Green函数的tight-binding方法,对pyrene分子的电子传导和电子流分布进行了理论研究。在考虑到界面耦合和Hopping积分的情况下,得出了电子透射谱和流分布的模拟结果。结果显示透射与电子的能量紧密相关;谱的振荡特征... 利用量子理论中基于Green函数的tight-binding方法,对pyrene分子的电子传导和电子流分布进行了理论研究。在考虑到界面耦合和Hopping积分的情况下,得出了电子透射谱和流分布的模拟结果。结果显示透射与电子的能量紧密相关;谱的振荡特征是能级量子化的结果;流分布有着特定的方向,并且在每一个原子点上符合Kirchhoff量子流守恒定律。另外还发现了桥接pyrene分子的正负能开关特性。 展开更多
关键词 石墨晶片 Pyrene分子 电导 电流分布
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Effects of Pyrene Stress on Growth and Physiological Indexes of Maize(Zea mays L.) Seedling
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作者 陈倩婷 许超 +2 位作者 陈旭磊 林世奇 吴启堂 《Agricultural Science & Technology》 CAS 2011年第1期37-40,57,共5页
[Objective]The paper was to explore the effects of pyrene stress on growth and physiological indexes of maize seedling.[Method] The effects of different concentrations of pyrene(0,0.5,1.0,and 2.0 mg/L) on growth and... [Objective]The paper was to explore the effects of pyrene stress on growth and physiological indexes of maize seedling.[Method] The effects of different concentrations of pyrene(0,0.5,1.0,and 2.0 mg/L) on growth and several physiological indexes,such as chlorophyll content,malnodiadehyde(MDA) content of both leaves and roots of maize(Zea Mays L.) seedlings of Shixiang 1(sensitive variety) and Guangtian 3(tolerant variety) were studied by a hydroponic experiment.[Result]As the concentration of prene increasing within the test concentration range,the contents of chlorophyll a and chlorophyll b in Shixiang 1 first increased and then decreased;relative growth yield and absolute growth rate showed the decreasing trend;MDA contents in roots and leaves showed the increasing trend.Relative growth yield,absolute growth rate and chlorophyll a content in Guangtian 3 first increased and then decreased;chlorophyll b and MDA contents in roots showed the increasing trend;MDA contents in leaves showed the decreasing trend.Compared with control,chlorophyll a and chlorophyll b contents of Shixiang 1 significantly increased under pyrene concentration of 0.5-1.0 mg/L,which significantly decreased as the concentration of pyrene ≥2.0 mg/L;MDA contents in roots and leaves significantly increased as the concentration of pyrene ≥1.0 mg/L,while relative growth yield and absolute growth rate significantly decreased.Chlorophyll a and chlorophyll b contents in Guangtian 3 significantly increased as the concentration of pyrene ≥1.0 mg/L.Pyrene concentration had significantly negative correlation with relative growth yield and absolute growth rate of Shixiang 1,while it had significant positive correlation with MDA contents in roots.Pyrene concentration had significant positive correlation with chlorophyll b and MDA contents in roots of tolerant variety Guangtian 3.[Conclusion]The study provided basis for the management measures of maize during its seedling stage. 展开更多
关键词 MAIZE Pyrene stress GROWTH Physiological indexes
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Usingvery long-range terrestriallaser scanner to analyze the temporal consistency of the snowpack distribution in a high mountain environment
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作者 Juan I.LOPEZ-MORENO Jesús REVUELTO +4 位作者 E.ALONSO-GONZALEZ Alba SANMIGUEL-VALLELADO Steven R.FASSNACHT Jeffrey DEEMS Enrique MORAN-TEJEDA 《Journal of Mountain Science》 SCIE CSCD 2017年第5期823-842,共20页
This study demonstrated the usefulness of very long-range terrestrial laser scanning(TLS) for analysis of the spatial distribution of a snowpack, to distances up to 3000 m, one of the longest measurement range reporte... This study demonstrated the usefulness of very long-range terrestrial laser scanning(TLS) for analysis of the spatial distribution of a snowpack, to distances up to 3000 m, one of the longest measurement range reported to date. Snow depth data were collected using a terrestrial laser scanner during 11 periods of snow accumulation and melting,over three snow seasons on a Pyrenean hillslopecharacterized by a large elevational gradient, steep slopes, and avalanche occurrence. The maximum and mean absolute snow depth error found was 0.5-0.6 and 0.2-0.3 m respectively, which may result problematic for areas with a shallow snowpack, but it is sufficiently accurate to determine snow distribution patterns in areas characterized by a thick snowpack. The results indicated that in most cases there was temporal consistency in the spatial distribution of thesnowpack, even in different years. The spatial patterns were particularly similar amongst thesurveys conducted during the period dominated by snow accumulation(generally until end of April), or amongst those conducted during the period dominated by melting processes(generally after mid of April or early May). Simple linear correlation analyses for the 11 survey dates, and the application of Random Forests analysis to two days representative of snow accumulation and melting periods indicated the importance of topography to the snow distribution. The results also highlight that elevation and the Topographic Position index(TPI) were the main variables explaining the snow distribution, especially during periods dominated by melting. The intra-and inter-annual spatial consistency of the snowpack distribution suggests that the geomorphological processes linked to presence/absence of snow cover act in a similar way in the long term, and that these spatial patternscan be easily identifiedthrough several years of adequate monitoring. 展开更多
关键词 SNOW Terrestrial laser scanner(TLS) Topography Random Forests Spatial distribution pyrenees
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Inhibitory effects of RRR-α-tocopheryl succinate on benzo (a) pyrene (B (a) P)-induced forestomach carcinogenesis in female mice 被引量:24
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作者 Kun Wu1 Yu Juan Shan1 +2 位作者 Yan Zhao1 Jian Wu Yu2 Bai He Liu1 1Department of Nutrition and Food Hygiene, School of Public Health, Harbin Medical University, Harbin 150001, Heilongjiang Province, China2The Second Affiliated Hospital, Harbin Medical University, Harbin 150001, Heilongjiang Province, China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第1期60-65,共6页
AIM To study the inhibitory effects of VES( RRR-α-tocopheryl Succinate, VES ), aderivative of natural Vitamin E, on benzo (a)pyrene (B (a) P)-induced forestomach tumor infemale mice.METHODS The model of B (a)P-induce... AIM To study the inhibitory effects of VES( RRR-α-tocopheryl Succinate, VES ), aderivative of natural Vitamin E, on benzo (a)pyrene (B (a) P)-induced forestomach tumor infemale mice.METHODS The model of B (a)P-inducedforestomach tumor was established according tothe methods of Wattenberg with slightmodifications. One hundred and eighty femalemice (6 weeks old) were divided into six groupsequally; negative control (Succinic acid),vehicle control ( Succinate + B (a) P), positivecontrol(B(a) P), high VES(2.5g/kg. b. w + B(a)P), Iow VES(1 .25 g/kg. b. w + B(a) P) ig as wellas VES by ip (20 mg/kg, b. w + B(a) P). Exceptthe negative control group, the mice wereadministrated with B(a)P ig. and correspondingtreatments for 4 weeks to study the anti-carcinogenetic effect of VES during the initiationperiod. The experiment lasted 29 weeks, inwhich the inhibitory effects of VES both ontumor incidence and tumor size were tested.RESULTS The models of B (a)P-inducedforestomach tumor in female mice wereestablished successfully. Some werecauliflower-like, others looked like papilla, evena few were formed into the ulcer cavities. VES at1.25 g/kg. b. w, 2.5 g/kg. b.w. by ig and 20 mg/kg. b. w. via ip could decrease the number oftumors per mouse (1.7 ± 0. 41, 1.6 ± 0.34 and 1.1±0.43), being lower than that of B(a)P group(5.4 ± 0.32, P<0.05). The tumor incidence wasinhibited by 18.2%, 23.1% and 50.0%. VES at1.25g/kg.b.w., 2.5 g/ kg.b.w. by ig and20 mg/kg. b.w. via ip reduced the total volumeof tumors per mouse (54.8 ± 8.84, 28.4 ± 8.32and 23.9± 16.05), being significantly lower thanthat of B(a)P group (150.2±20.93, P<0.01).The inhibitory rates were 63.5%, 81.1% and84.1%, respectively.CONCLUSION VES has inhibitory effects on B(a) P-induced forestomach carcinogenesis infemale mice, especially by ip and it may be apotential anti-cancer agent in vivo. 展开更多
关键词 stomach neoplasms ANTINEOPLASTIC agents vitamin E transforming growth factors apoptosis benzo(a) PYRENE
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Biodegradation of benzo[a]pyrene in soil by Mucor sp.SF06 and Bacillus sp.SB02 co-immobilized on vermiculite 被引量:32
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作者 SU Dan LI Pei-jun +1 位作者 FRANK Stagnitti XIONG Xian-zhe 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第6期1204-1209,共6页
Two indigenous microorganisms, Bacillus sp. SB02 and Mucor sp. SF06, capable of degrading polycyclic aromatic hydrocarbons (PAHs) were co-immobilized on vermiculite by physical adsorption and used to degrade benzo[a... Two indigenous microorganisms, Bacillus sp. SB02 and Mucor sp. SF06, capable of degrading polycyclic aromatic hydrocarbons (PAHs) were co-immobilized on vermiculite by physical adsorption and used to degrade benzo[a] pyrene (BaP). The characteristics of BaP degradation by both free and co-immobilized microorganism were then investigated and compared. The removal rate using the immobilized bacterial-fungal mixed consortium was higher than that of the freely mobile mixed consortium. 95.3% of BaP was degraded using the co-immobilized system within 42 d, which was remarkably higher than the removal rate of that by the free strains. The optimal amount of inoculated co-immobilized system for BaP degradation was 2%. The immobilized bacterial-fungal mixed consortium also showed better water stability than the free strains. Kinetics of BaP biodegradation by co-immobilized SF06 and SB02 were also studied. The results demonstrated that BaP degradation could be well described by a zero-order reaction rate equation when the initial BaP concentration was in the range of 10--200 mg/kg. The scanning electronic microscope (SEM) analysis showed that the co-immobilized microstructure was suitable for the growth of SF06 and SB02. The mass transmission process of co-immobilized system in soil is discussed. The results demonstrate the potential for employing the bacterial-fungal mixed consortium, co-immobilized on vermiculite, for in situ bioremediation of BaP. 展开更多
关键词 BIODEGRADATION Bacillus sp. SB02 Mucor sp. SF06 BENZO[A]PYRENE immobilization soil pollution
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