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Ultra-high-field magnetic resonance:Why and when? 被引量:1
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作者 Ewald Moser 《World Journal of Radiology》 CAS 2010年第1期37-40,共4页
This paper briefly summarizes the development of magnetic resonance imaging and spectroscopy in medicine.Aspects of magnetic resonancephysics and-technology relevant at ultra-high magnetic fields as well as current li... This paper briefly summarizes the development of magnetic resonance imaging and spectroscopy in medicine.Aspects of magnetic resonancephysics and-technology relevant at ultra-high magnetic fields as well as current limitations are highlighted.Based on the first promising studies,potential clinical applications at 7 Tesla are suggested.Other aims are to stimulate awareness of the potential of ultra-high field magnetic resonance and to stimulate active participation in much needed basic or clinical research at 7 Tesla or higher. 展开更多
关键词 Alzheimer’s disease Brain tumors CARTILAGE Functional MAGNETIC RESONANCE imaging MAGNETIC RESONANCE MAGNETIC RESONANCE spectroscopy Multiple SCLEROSIS Ultra-high field MAGNETIC RESONANCE methods
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Geology of the Copper Mineralization in Proterozoic Ajabgarh Meta-Sediments of, Dokan-Dariba Belt, Sikar District Rajasthan Northwestern India
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作者 Rajendra Kumar Sharma 《Open Journal of Geology》 CAS 2023年第5期384-430,共47页
The Khetri copper belt is a well-known metallotect in northern part of Delhi fold belt in Rajasthan. On the eastern margin of the Khetri sub basin of North Delhi basin separated by a basement high, another sub basin A... The Khetri copper belt is a well-known metallotect in northern part of Delhi fold belt in Rajasthan. On the eastern margin of the Khetri sub basin of North Delhi basin separated by a basement high, another sub basin Alwar-Ajabgarh sub basin exposes that a thick sequence of Ajabgarh group of rocks overlies a thick arenaceous sequence of Alwar group of Delhi Super Group of rocks. The Ajabgarh meta sediments here in the Neem Ka thana area are characterized by presence of Bornite dominated copper mineralization with silver association and minor presence of Pb. The mineralization has been described by various workers as strata-bound, hypogene and IOCG. But these inferences are based on part information and the inference drawn is sectorial in nature. The current study includes a holistic study based on exploration over a period of more than two decades and the data generated suggest thereof, that this syngenetic sulphide mineralization associated with the sedimentation of marl and carbonate rocks. Subsequently it has been relocated during 2<sup>nd</sup> deformation accompanied by epigenetic component of mineralization depicted in terms of vein filled coarse grained aggregates of bornite and chalcopyrite disposed across the general disposition of litho-package. The EPMA and fluid inclusion data generated from the area indicate association of typical hydrothermal environment minerals like, Perkrite, Wittchenite, Aguilarite, Molybdnite etc. The mineralizing fluids have been trapped between the temperature ranges of 130°C to 375°C with average being 250°C to 300°C. The fluid salinity also varies from near pure hot water to moderately saline fluid indicative of multi-episodic mineralization of syngenetic nature coupled with epigenetic component. The ore textures indicate 500°C temperature range;certain intergrowths of minerals like specular hematite and bornite suggest the occurrence of hypogene environment induced due to emplacement of granite/pegmatite on the eastern and southern margins of the belt. The strata bound nature suggests the euxogenic environment facilitated by carbonate facies of rocks. The parallelism of sulphide with the rock fabric was attained during first deformation and the epigenetic component coupled with the hypogene assemblage was deposited during the D<sub>2</sub> deformation in the brittle ductile shear zones and limb shears, between the temperature ranges of 130°C to 570°C as deduced from petrochemical data. Hence a comprehensive model is suggested here on evolution of process of mineralization in the Neem Ka Thana belt. 展开更多
关键词 Proterozoic Copper Mineralization Ajabgarh Meta Sediments Dariba-Dokan Belt Neemka Thana. Northwestern India
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Data-driven Simulations of Magnetic Field Evolution in Active Region 11429:Magneto-frictional Method Using PENCIL CODE
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作者 P.Vemareddy Jorn Warnecke Ph.A.Bourdin 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第2期74-82,共9页
Coronal magnetic fields evolve quasi-statically over long timescales and dynamically over short timescales.As of now there exist no regular measurements of coronal magnetic fields,and therefore generating the coronal ... Coronal magnetic fields evolve quasi-statically over long timescales and dynamically over short timescales.As of now there exist no regular measurements of coronal magnetic fields,and therefore generating the coronal magnetic field evolution using observations of the magnetic field at the photosphere is a fundamental requirement to understanding the origin of transient phenomena from solar active regions(ARs).Using the magneto-friction(MF)approach,we aim to simulate the coronal field evolution in the solar AR 11429.The MF method is implemented in the open source PENCIL CODE along with a driver module to drive the initial field with different boundary conditions prescribed from observed vector magnetic fields at the photosphere.In order to work with vector potential and the observations,we prescribe three types of bottom boundary drivers with varying free-magnetic energy.The MF simulation reproduces the magnetic structure,which better matches the sigmoidal morphology exhibited by Atmospheric Imaging Assembly(AIA)images at the pre-eruptive time.We found that the already sheared field further driven by the sheared magnetic field will maintain and further build the highly sheared coronal magnetic configuration,as seen in AR 11429.Data-driven MF simulation is a viable tool to generate the coronal magnetic field evolution,capturing the formation of the twisted flux rope and its eruption. 展开更多
关键词 SUN corona-Sun evolution-Sun magnetic fields-Sun photosphere
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A survey of data-centric technologies supporting decision-making before deploying military assets
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作者 Alexandra Zabala-López Mario Linares-Vásquez +1 位作者 Sonia Haiduc Yezid Donoso 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第12期226-246,共21页
In a time characterized by the availability of vast amounts of data,the effective utilization of information is critical for timely decision-making in military operations.However,processing large amounts of data requi... In a time characterized by the availability of vast amounts of data,the effective utilization of information is critical for timely decision-making in military operations.However,processing large amounts of data requires computational resources and time.Therefore,decision makers have used data-centric technologies to take advantage of public and private data sources to support military operations.This survey explores the integration and application of data-centric technologies,such as data analytics,data science,and machine learning,to optimize decision-making workflows within military contexts supporting the deployment of military assets and resources.To address the information gap,this article presents a literature review,specifically a survey.Our survey examines the use of the mentioned technologies to process and analyze information that contributes to the phases of situational awareness,and planning in military environments.We then introduce a taxonomy of the approaches associated with implementing these technologies in military scenarios.Furthermore,we discuss relevant factors for the seamless integration of data-centric technologies into military decision-making processes,and reveal the importance of specialized personnel,architectures,and cybersecurity issues in the task of developing prototypes and models.The findings of this paper aim to provide valuable insights for military institutions,offering a deeper understanding of the use of data-centric technologies as innovative practices to enhance the effectiveness of military decision-making. 展开更多
关键词 Data-centric technologies MILITARY ANALYTICS Machine learning Data science Artificial intelligence
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Creep Modeling of Magnesia-chromite Bricks in a RH Snorkel During a Process Cycle 被引量:2
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作者 JIN Shengli Harald HARMUTH +1 位作者 Dietmar GRUBER Roman RSSLER 《China's Refractories》 CAS 2015年第1期22-25,共4页
In this paper both experimental and analytical approaches to provide the inputs for creep modeling of refractories including a newly developed high temperature compressive creep machine and an inverse estimation proce... In this paper both experimental and analytical approaches to provide the inputs for creep modeling of refractories including a newly developed high temperature compressive creep machine and an inverse estimation procedure of creep law parameters are briefly introduced.Besides,a modified shear test is applied to determine the cohesion and friction angle of refractories under shear state. A RH snorkel equipped with magnesia- chromite bricks is chosen for a case study of thermomechanical simulation applying the classical creep model and Drucker-Prager creep model available in the finite element code ABAQUS,respectively. Afterwards,thermal stresses and joint opening of magnesia- chromite bricks during a process cycle are compared to distinguish the impact of these two creep models. 展开更多
关键词 creep shear failure thermomechanical modeling RH snorkel
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Chronic effects of stretching on range of motion with consideration of potential moderating variables:A systematic review with meta-analysis 被引量:2
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作者 Andreas Konrad Shahab Alizadeh +7 位作者 Abdolhamid Daneshjoo Saman Hadjizadeh Anvar Andrew Graham Ali Zahiri Reza Goudini Chris Edwards Carina Scharf David George Behm 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期186-194,共9页
Background:It is well known that stretch training can induce prolonged increases in joint range of motion(ROM).However,to date more information is needed regarding which training variables might have greater influence... Background:It is well known that stretch training can induce prolonged increases in joint range of motion(ROM).However,to date more information is needed regarding which training variables might have greater influence on improvements in flexibility.Thus,the purpose of this metaanalysis was to investigate the effects of stretch training on ROM in healthy participants by considering potential moderating variables,such as stretching technique,intensity,duration,frequency,and muscles stretched,as well as sex-specific,age-specific,and/or trained state-specific adaptations to stretch training.Methods:We searched through PubMed,Scopus,Web of Science,and SportDiscus to find eligible studies and,finally,assessed the results from 77 studies and 186 effect sizes by applying a random-effect meta-analysis.Moreover,by applying a mixed-effect model,we performed the respective subgroup analyses.To find potential relationships between stretch duration or age and effect sizes,we performed a meta-regression.Results:We found a significant overall effect,indicating that stretch training can increase ROM with a moderate effect compared to the controls(effect size=-1.002;Z=-12.074;95%confidence interval:-1.165 to-0.840;p<0.001;I^(2)=74.97).Subgroup analysis showed a significant difference between the stretching techniques(p=0.01)indicating that proprioceptive neuromuscular facilitation and static stretching produced greater ROM than did ballistic/dynamic stretching.Moreover,there was a significant effect between the sexes(p=0.04),indicating that females showed higher gains in ROM compared to males.However,further moderating analysis showed no significant relation or difference.Conclusion:When the goal is to maximize ROM in the long term,proprioceptive neuromuscular facilitation or static stretching,rather than ballistic/dynamic stretching,should be applied.Something to consider in future research as well as sports practice is that neither volume,intensity,nor frequency of stretching were found to play a significant role in ROM yields. 展开更多
关键词 FLEXIBILITY Long-term stretching Stretch training
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Characterisation of Submicron-Grain Sized Yttria-Stabilised Zirconia Electrolyte for SOFCs
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作者 Min Nah Tong Jon Binner +2 位作者 Christopher Munnings Bala Vaidhyanathan Hirad Taherparvar 《材料科学与工程(中英文版)》 2011年第2期177-183,共7页
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Phylogenetic insights resolve Dacampiaceae(Pleosporales)as polyphyletic:Didymocyrtis(Pleosporales,Phaeosphaeriaceae)with Phoma-like anamorphs resurrected and segregated from Polycoccum(Trypetheliales,Polycoccaceae fam.nov.) 被引量:3
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作者 Damien Ertz Paul Diederich +5 位作者 James D.Lawrey Franz Berger Colin E.Freebury Brian Coppins Alain Gardiennet Josef Hafellner 《Fungal Diversity》 SCIE 2015年第5期53-89,共37页
A phylogenetic analysis of nuLSU and ITS sequences representing genera previously included in Dacampiaceae indicates that the family is strongly polyphyletic and that the type species of Dacampia is placed in Pleospor... A phylogenetic analysis of nuLSU and ITS sequences representing genera previously included in Dacampiaceae indicates that the family is strongly polyphyletic and that the type species of Dacampia is placed in Pleosporales.The genus Munkovalsaria s.str.is placed in Didymosphaeriaceae(Pleosporales).Polycoccum s.str.and two species of Clypeococcum are shown to form a new lineage sister to the Trypetheliaceae in Trypetheliales and described here as Polycoccaceae.Other members of Polycoccum s.lat.are included in the Pleosporales and are closely related to lichenicolous Phoma-like species of the family Phaeosphaeriaceae.The genus Didymocyrtis is resurrected for these species and for lichenicolous species previously assigned to Diederichia,Diederichomyces,Leptosphaeria and Phoma.The genera Diederichia and Diederichomyces are synonymized with Didymocyrtis.The new combinations Didymocyrtis bryonthae,D.cladoniicola,D.foliaceiphila,D.infestans,D.kaernefeltii,D.melanelixiae,D.pseudeverniae,D.ramalinae,D.slaptoniensis and D.xanthomendozae are made,and the new name D.epiphyscia is introduced for Phoma physciicola.Some anamorph-teleomorph relationships are resolved,such as Didymocyrtis ramalinae–Phoma ficuzzae and Didymocyrtis consimilis–Phoma caloplacae,the phylogenetic results being supported by single ascospore cultures that lead to the asexual stage producing pycnidia and conidia in culture.Speciation by host switching is assumed to be important in the genus Didymocyrtis.An identification key to Didymocyrtis species is provided. 展开更多
关键词 DOTHIDEOMYCETES LEPTOSPHAERIA Diederichia Diederichomyces Lichenicolous fungi Phylogeny
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Structure of the Barud Dome Complex,Eastern Desert,Egypt:Insights from Crustal Origins in the Northern Basement Terrains of the Arabian-Nubian Shield
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作者 Farid MAKROUM Mohamed BADAWI +3 位作者 Kurt STÜWE Norbert NÉMETH Mahmoud ABDELATIF Ahmed SHALABY 《Acta Geologica Sinica(English Edition)》 2025年第2期370-393,共24页
The Barud gneissic dome complex is situated along the ENE-trending dextral shear zone of the Qena-Safaga Line that serves as a significant tectonic boundary between the basement terrains of the Northern and Central Ea... The Barud gneissic dome complex is situated along the ENE-trending dextral shear zone of the Qena-Safaga Line that serves as a significant tectonic boundary between the basement terrains of the Northern and Central Eastern Desert.These terrains exhibit distinct differences in crustal composition and deformation style.The Northern Eastern Desert and its extension into Sinai are predominantly composed of gneissic granites that are intruded by large batholiths of calc-alkaline and alkaline granites.Conversely,the Central and Southern Eastern Desert are commonly blanketed by a carapace of ophiolite-bearing volcano-sedimentary rocks of the Pan-African cover nappes.These northern terrains,just north of the Barud dome complex,the crust underwent significant NW-SE regional crustal extension across the Qena-Safaga Line,which sharply delineates the northern limit of the transpressional deformations linked to the Najd fault system in the Central and Southern Eastern Desert.Through comprehensive geological mapping and the integration of various geophysical,geochemical and geochronological data,this paper offers explanations for the contrasting geological features of the basement terrains on both sides of the Qena-Safaga Line and its analogous Fatira Shear Zone that plays a significant role in tectonic modeling of the Barud dome complex region.The Barud gneissic protolith experienced crustal shortening approximately 697 million years ago in the NW-SE direction,initiating dextral motion along the Fatira Shear Zone.Large batholiths of granodiorite/tonalite complex intruded the Barud gneissic dome protolith around 630 million years ago along the Qena-Safaga Line,at relatively shallow crustal depths,following the same orientation as the earlier shortening direction.Ongoing magmatic activity along the Qena-Safaga Line indicates intense magmatic underplating,resulting in significant intrusions of granodioritic melts into the early rifted crust of the Northern Eastern Desert and Sinai terrains.The crust of these northern terrains likely underwent isostatic compensation through uplifting and subsequent erosion.The disappearance of ophiolite-bearing belts and the presence of Paleo-to Mesoproterozoic continental-derived cobbles and ignimbrites in Sinai metasedimentary belts and Northern Eastern Desert molasse basins suggest that the northern terrains,located north of the Qena-Safaga Line,originated as a cohesive,thin continental crust that rifted off the eastern passive margin of the Sahara Metacraton during the early Neoproterozoic rifting of the Rodinia supercontinent. 展开更多
关键词 GRANITE shear zone Qena-Safaga Line Pan-African Orogeny
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一种基于SAR ADC的数字温度传感器
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作者 王洋 刘依桦 +2 位作者 郭宇锋 高昊 张翼 《电子器件》 2025年第4期932-936,共5页
基于SAR ADC结构采用0.18μm CMOS工艺设计实现了一种宽温度区间传感器单片集成电路。感温电路基于双极型晶体管的PTAT特性设计,并使用动态匹配技术减小失配,使用斩波技术减小噪声。为了在宽感温区间工作,在SAR ADC的逻辑部分设计了一... 基于SAR ADC结构采用0.18μm CMOS工艺设计实现了一种宽温度区间传感器单片集成电路。感温电路基于双极型晶体管的PTAT特性设计,并使用动态匹配技术减小失配,使用斩波技术减小噪声。为了在宽感温区间工作,在SAR ADC的逻辑部分设计了一种改进的TSPC寄存器。仿真结果显示芯片可在-110℃~+120℃温度区间内工作,测温精度为-3.2℃~+3.3℃。芯片内核面积为0.42 mm^(2),功耗为9.76 mW。 展开更多
关键词 温度传感器 感温电路 SAR ADC 模拟集成电路
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Influence of phytoplankton,bacteria and viruses on nutrient supply in tropical waters 被引量:1
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作者 Zhi Yang Sim Kwan Chien Goh +3 位作者 Nur Hanisah binte Sukarji Feijian Mao Yiliang He Karina Yew-Hoong Gin 《Journal of Environmental Sciences》 2025年第5期174-186,共13页
Diel investigations of water environments are one means to holistically understand the dynamics and functional roles of phytoplankton,bacteria and viruses in these ecosystems.They have the potential to substantially i... Diel investigations of water environments are one means to holistically understand the dynamics and functional roles of phytoplankton,bacteria and viruses in these ecosystems.They have the potential to substantially impact carbon(C),nitrogen(N)and phosphorus(P)biogeochemistry through their respective roles.This study characterizes the phytoplankton,bacteria and virus communities and the elemental composition of various C,N and P nutrients flow over three diel cycles in tropical urban lake.Our results show that ratios of C:N:P fluctuated strongly from the lack of dissolved organic phosphorus(DOP)and PO_(4).Specifically,green algae peaked during day time and exudate dissolved organic matter(DOM)that strongly modulate dissolved organic carbon(DOC):DOP ratio to diel DOP limitation.Multiple linear regression and Stella modelling emphasize the roles of viruses together with Synechococcus as important nutrient recyclers of NH_(4)and PO_(4)in nutrients-limited waters.Respective normalised surface PO_(4)and combined surface and bottom NH_(4)concentration selected both viruses and Synechococcus as important drivers.Process model of N and P biogeochemical cycles can achieve 69%and 57%similar to observed concentration of NH_(4)and PO_(4),respectively.A short latent period of 9 hr was calculated,in addition to the calibrated high infectivity of viruses to Synechococcus.Taken together,the rapid turn-over between Synechococcus and viruses has biogeochemical significance,where the rapid recycling of essential nutrients allows for shortcuts in the N and P cycle,supporting a wide range of microbes. 展开更多
关键词 DIEL PHYTOPLANKTON BACTERIA Virus NUTRIENTS Element ratios
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How to determine the leaf area index(LAI)of forests:A comparison of forest inventory versus satellite-driven estimates
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作者 Muhammed Sinan Hubert Hasenauer 《Forest Ecosystems》 2025年第4期750-759,共10页
Leaf area index(LAI)is a key measure of forest stand physiology and biomass production,and is essential within ecosystem modeling.There are two common approaches to obtaining LAI:(i)terrestrial forest inventory-based... Leaf area index(LAI)is a key measure of forest stand physiology and biomass production,and is essential within ecosystem modeling.There are two common approaches to obtaining LAI:(i)terrestrial forest inventory-based“bottom-up”,and(ii)satellite-based“top-down”techniques.The purpose of this study is to compare terrestrial LAI from allometric functions applied to more than 30,000 trees of the Austrian National Forest Inventory(NFI)vs.satellite-based LAI estimates obtained from moderate resolution imaging spectroradiometer(MODIS)and Sentinel(Sentinel-3 TOC reflectance and PROBA-V)data across Austrian forests.We analyzed a satellite pixelto-plot aggregation and obtained the full inventory data set for the LAI comparison.The results suggest that terrestrial vs.satellite(MODIS and Sentinel)driven LAI estimates are consistent,but(i)the variation of the terrestrial forest inventory LAI is larger vs.the pixel average LAI from satellite data,and(ii)any satellite LAI estimation needs a forest stand density correction if the crown competition factor(CCF),a measure for stand density,is<250 to avoid an overestimation in LAI. 展开更多
关键词 ALLOMETRY Moderate resolution imaging spectroradiometer(MODIS) SENTINEL Forest management Stand density Ecosystem modeling Remote sensing
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Identifying suitable areas for plenter forest management
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作者 Mathias Leiter Christoph Pucher +4 位作者 Michael Kessler Ferdinand Honigsberger Manfred J.Lexer Harald Vacik Hubert Hasenauer 《Forest Ecosystems》 2025年第1期83-92,共10页
Plenter forests,also known as uneven-aged or continuous cover forests enhance forest resilience and resistance against disturbances compared to even-aged forests.They are considered as an adaptation option to mitigate... Plenter forests,also known as uneven-aged or continuous cover forests enhance forest resilience and resistance against disturbances compared to even-aged forests.They are considered as an adaptation option to mitigate climate change effects.In this study,we present a conceptual approach to determine the potentially suitable area for plenter forest management within central European mixed species forests and apply our approach to the case study area in Styria,the south-eastern Province of Austria.The concept is based on ecological and technicaleconomic constraints and considers expected future climate conditions and its impact on plenter forest management.For each 1 ha forest pixel,we assess the ecological conditions for plenter forest management according to the autecological growth conditions of silver fir,and at least one additional shade tolerant tree species.The technical-economic constraints are defined by slope(≤30%)and distance to the next forest road(≤100 m)to ensure cost-efficient harvesting.The results show that under current climate conditions 28.1%or 305,349 ha of the forests in Styria are potentially suitable for plenter forest management.For the years 2071–2100 and under the climate change scenario RCP 4.5,the potential area decreases to 286,098 ha(26.3%of the total forest area)and for the scenario RCP 8.5 to 208,421 ha(19.1%of the total forest area).The main reason for these changes is the unfavourable growing conditions for silver fir in the lowlands,while in the higher elevations silver fir is likely to expand.Our results may serve forest managers to identify areas suitable for plenter forests and assist in the transformation of even-aged pure forests to uneven-aged forests to increase resistance,resilience,and biodiversity under climate change. 展开更多
关键词 Plenter forest Uneven-aged forest management Tree species suitability Tree harvesting Transformation
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Optimal integration of forest inventory data and aerial image-based canopy height models for forest stand management
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作者 Ardalan Daryaei Zoran Trailovic +3 位作者 Hormoz Sohrabi Clement Atzberger Eduard Hochbichler Markus Immitzer 《Forest Ecosystems》 2025年第3期443-453,共11页
Accurate,reliable,and regularly updated information is necessary for targeted management of forest stands.This information is usually obtained from sample-based field inventory data.Due to the time-consuming and costl... Accurate,reliable,and regularly updated information is necessary for targeted management of forest stands.This information is usually obtained from sample-based field inventory data.Due to the time-consuming and costly procedure of forest inventory,it is imperative to generate and use the resulting data optimally.Integrating field inventory information with remote sensing data increases the value of field approaches,such as national forest inventories.This study investigated the optimal integration of forest inventory data with aerial image-based canopy height models(CHM)for forest growing stock estimation.For this purpose,fixed-area and angle-count plots from a forest area in Austria were used to assess which type of inventory system is more suitable when the field data is integrated with aerial image analysis.Although a higher correlation was observed between remotely predicted growing stocks and field inventory values for fixed-area plots,the paired t-test results revealed no statistical difference between the two methods.The R2 increased by 0.08 points and the RMSE decreased by 7.7 percentage points(24.8m^(3)·ha^(−1))using fixed-area plots.Since tree height is the most critical variable essential for modeling forest growing stock using aerial images,we also compared the tree heights obtained from CHM to those from the typical field inventory approach.The result shows a high correlation(R^(2)=0.781)between the tree heights extracted from the CHM and those measured in the field.However,the correlation decreased by 0.113 points and the RMSE increased by 4.2 percentage points(1.04m)when the allometrically derived tree heights were analyzed.Moreover,the results of the paired t-test revealed that there is no significant statistical difference between the tree heights extracted from CHM and those measured in the field,but there is a significant statistical difference when the CHM-derived and the allometrically-derived heights were compared.This proved that image-based CHM can obtain more accurate tree height information than field inventory estimations.Overall,the results of this study demonstrated that image-based CHM can be integrated into the forest inventory data at large scales and provide reliable information on forest growing stock.The produced maps reflect the variability of growth conditions and developmental stages of different forest stands.This information is required to characterize the status and changes,e.g.,in forest structure diversity,parameters for volume,and can be used for forest aboveground biomass estimation,which plays an important role in managing and controlling forest resources in mid-term forest management.This is of particular interest to forest managers and forest ecologists. 展开更多
关键词 Forest inventory Growing stock Fixed-area plot Angle-count plot Aerial imagery Tree height Random forest regression
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LOG-CONCAVITY OF THE FIRST DIRICHLET EIGENFUNCTION OF SOME ELLIPTIC DIFFERENTIAL OPERATORS AND CONVEXITY INEQUALITIES FOR THE RELEVANT EIGENVALUE
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作者 Andrea COLESANTI 《Acta Mathematica Scientia》 2025年第1期143-152,共10页
Given an open bounded subset Ω of ℝ^(n) we consider the eigenvalue problem{Δu-(■u,■V)=-λvu,u>0inΩ,u=0 onδΩ,where V is a given function defined inΩandλV is the relevant eigenvalue.We determine sufficient c... Given an open bounded subset Ω of ℝ^(n) we consider the eigenvalue problem{Δu-(■u,■V)=-λvu,u>0inΩ,u=0 onδΩ,where V is a given function defined inΩandλV is the relevant eigenvalue.We determine sufficient conditions on V such that ifΩis convex,the solution u is log-concave.We also determine sufficient conditions ensuring that λ_(V),as a function of the setΩ,verifies a convexity inequality with respect to the Minkowski addition of sets. 展开更多
关键词 EIGENVALUE LOG-CONCAVITY elliptic operator Brunn-Minkowski inequality convex body
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Enhancing plasticity of metallic glasses via rejuvenation:A review
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作者 Quan DONG Cai-ju LI +2 位作者 Baran SARAC Jürgen ECKERT Jun TAN 《Transactions of Nonferrous Metals Society of China》 2025年第12期3961-3984,共24页
Recent attention has been directed towards tailoring the internal structure and enhancing the plasticity of metallic glasses(MGs)via rejuvenation treatments.This work aims to comprehensively review the various approac... Recent attention has been directed towards tailoring the internal structure and enhancing the plasticity of metallic glasses(MGs)via rejuvenation treatments.This work aims to comprehensively review the various approaches and underlying mechanisms of inducing rejuvenation in MGs,including thermal-activated methods for deep-cooling cycling treatments and annealing-induced regeneration,mechanical-driven methods of pre-elastic loading and plastic deformation,thermo-mechanically coupled methods for thermo-mechanical creep and thermoplastic forming,and irradiation-induced rejuvenation.Additionally,strategies such as gradient rejuvenation for promoting a favorable distribution of free volume gradients to deflect shear bands are discussed for enhancing plasticity.Finally,the review delves into the challenges and prospects associated with advancing the development of MGs exhibiting high plasticity at ambient conditions.This review is anticipated to contribute to fostering a systematic understanding of the diverse methods and mechanisms employed to enhance the plasticity of MGs via rejuvenation treatments. 展开更多
关键词 metallic glass PLASTICITY REJUVENATION free volume shear band
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Simultaneously enhancing strength,ductility,and stiffness of lightweight multicomponent Mg−Al−Zn−Cu−Ce alloys
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作者 Zuo-hong GU Yun-xuan ZHOU +8 位作者 Jia-xing PENG Guang-ming HE Hao LV Quan DONG Jun TAN Xian-hua CHEN Bin JIANG Fu-sheng PAN Jürgen ECKERT 《Transactions of Nonferrous Metals Society of China》 2025年第10期3240-3255,共16页
To obtain lightweight multicomponent magnesium alloys with high tensile strength,ductility,and stiffness,two extruded Mg_(92−5x)Al_(1.5+3x)Zn_(3)Cu_(3.5+x)Ce_(x)(x=0.5 and 1,labeled as C0.5 and C1)alloys were designed... To obtain lightweight multicomponent magnesium alloys with high tensile strength,ductility,and stiffness,two extruded Mg_(92−5x)Al_(1.5+3x)Zn_(3)Cu_(3.5+x)Ce_(x)(x=0.5 and 1,labeled as C0.5 and C1)alloys were designed.The results reveal that the ultimate tensile strength,yield strength(YS),and fracture strain of the C0.5 alloy are simultaneously improved compared to those of the C1 alloy,with values of 346 MPa,312 MPa,and 11.7%,respectively.This enhancement is primarily attributed to the refinement of numerous secondary phases(micron scale Al_(3)CuCe,micron scale MgZnCu,and nanoscale MgZnCu phases).The calculation of YS shows that the Orowan strengthening and coefficient of thermal expansion mismatch strengthening are the main strengthening mechanisms,and the contribution values of both to the YS are 28 and 70 MPa for C0.5 alloy.In addition,the C0.5 alloy has a greater plasticity than the C1 alloy because the<c+a>slip system is initiated. 展开更多
关键词 Mg−Al−Zn−Cu−Ce alloy Al_(3)CuCe phase strengthening mechanism plastic deformation mechanism mechanical properties
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Cancer risk in IBD: How to diagnose and how to manage DALM and ALM 被引量:7
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作者 Helmut Neumann Michael Vieth +2 位作者 Cord Langner Markus F Neurath Jonas Mudter 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第27期3184-3191,共8页
The risk of developing neoplasia leading to colorectal cancer is significantly increased in ulcerative colitis (UC) and most likely in Crohn's disease. Several endoscopic surveillance strategies have been implemen... The risk of developing neoplasia leading to colorectal cancer is significantly increased in ulcerative colitis (UC) and most likely in Crohn's disease. Several endoscopic surveillance strategies have been implemented to identify these lesions. The main issue is that colitisassociated neoplasms often occurs in flat mucosa, often being detected on taking random biopsies rather than by identification of these lesions via endoscopic imaging. The standard diagnostic procedure in long lasting UC is to take four biopsies every 10 cm. Image enhancement methods, such as chromoendoscopy and virtual histology using endomicroscopy, have greatly im- proved neoplasia detection rates and may contribute toreduced random biopsies by taking targeted "smart" biopsies. Chromoendoscopy may effectively be performed by experienced endoscopists for routine screening of UC patients. By contrast, endomicroscopy is often only available in selected specialized endoscopic centers. Importantly, advanced endoscopic imaging has the poten- tial to increase the detection rate of neoplasia whereas the interplay between endoscopic experience and interpretation of histological biopsy evaluation allows the physician to make a proper diagnosis and to find the appropriate therapeutic approach. Colitis-associated intraepithelial neoplasms may occur in flat mucosa of endoscopically normal appearance or may arise as dysplasia-associated lesion or mass (DALM), which may be indistinguishable from sporadic adenomas in healthy or non-colitis mucosa [adenoma-like mass (ALM)]. The aim of this review was to summarize endoscopic and histological characteristics of DALM and ALM in the context of therapeutic procedures. 展开更多
关键词 Inflammatory bowel disease Crohn’s dis- ease Endoscopy Colitis Dysplasia-associated lesion or mass Adenoma-like mass ENDOMICROSCOPY Ulcerative colitis ENDOMICROSCOPY Confocal laser endomicroscopy Probe-based confocal laser endomicroscopy Integrated confocal laser endomicroscopy Endoscope-based confocal laser endomicroscopy Narrow band imaging CHROMOENDOSCOPY Cancer DYSPLASIA
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Eocene Weathering Oscillations Imprinted in Marl Mineral and Geochemical Record,Dinaric Foreland Basin,Croatia
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作者 Marija Horvat Nenad Tomasic +9 位作者 Dunja Aljinovic Damir Buckovic Stjepan Coric Vlasta Cosovic Igor Felja Ines Galovic Zeljko Istuk Stefica Kampic Drazen Kurtanjek Durdica Pezelj 《Journal of Earth Science》 2025年第3期1236-1250,共15页
Hemipelagic to pelagic(H/P)marls,representing pelitic deposits,accumulated within the foredeep sub-basin of the Dinaric Foreland Basin(northern Neotethyan margin,present-day Croatia)during the Middle to Late Eocene.Sy... Hemipelagic to pelagic(H/P)marls,representing pelitic deposits,accumulated within the foredeep sub-basin of the Dinaric Foreland Basin(northern Neotethyan margin,present-day Croatia)during the Middle to Late Eocene.Syn-sedimentary tectonic movements,paleogeographic position and exchanges of short-lived hyperthermal episodes affected the sedimentation and related mineral and geochemical record of these deposits.Mineral(clay)assemblages bear signature of prevailing physical weathering with significant illite and chlorite content,but climatic seasonality is suggested by smectite-interlayered phases and sporadical increase of kaolinite content.Illite crystallinity varies significantly,and the lowest crystallinity is recorded by the Lutetian samples.Illite chemistry index is always bellow 0.5,being characteristic for Fe-Mg-rich illite.The geochemical records are the most prominent(CIA up to 76,CIW up to 91)for the Istrian Lutetian(42.3-40.5 Ma),but also for Priabonian(35.8-34.3 Ma)samples of Hvar Island.The ICV values(the lowest 1.40 and the highest 10.85)of all studied samples fall above PAAS(ICV=0.85)and point to their chemical immaturity.The Ga/Rb ratios are lower than 0.2 and K_(2)O/Al_(2)O_(3) ratios are also low(0.16-0.22),implying transition between cold and dry,and warm and humid climate,obviously trending among several warming episodes. 展开更多
关键词 mineral and geochemical proxies MARLS EOCENE Dinaric Foreland Basin climate change geochemistry
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