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Assessing Sustainability of Land Management Using a Risk Identification Model

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pedosphere 2003年第1期13卷 41-48页

作者： p.R.STepHeNS A.e.Hewitt 等 LandcareResearch PrivateBag11052PalmerstonNorth（NewZealand） LandcareResearch.p.O.Box69 Lincoln（NewZealand）

New Zealand is highly dependent on its soil resource for continued agricultural production. To avoiddepleting this resource, there is a need to identify soils and associated land management practices wherethere is a risk of soil degradation. environmental integrity and ecosystem services also need to be ***, to ensure sustainable production, the on- and off-site environmental impacts of land managementneed to be identified and managed. We developed a structural vulnerability index for New Zealand soils. Thisindex ranks soils according to their inherent susceptibility to physical degradation when used for agricultural(pasture, forestry and cropping) purposes. We also developed a rule-based model to assess soil compactionvulnerability by characterising the combined effects of resistance and resilience. Other soil attributes havebeen appraised using seven chemical, physical and biological indicators of soil quality. These indicators havebeen applied in a nation-wide project involving data collection from over 500 sites for a range of land *** soil quality data can be interpreted via the World Wide Web - through the interactive decision-support tool SINDI. The land-use impact model is a framework to assess agricultural land management andenvironmental sustainability, and may be applied to land units at any scale. Using land resource data andinformation the model explicitly identifies hazards to land productivity and environmental integrity. It utilisesqualitative expert and local knowledge and quantitative model-based evaluations to assess the potentialenvironmental impacts of land-management practices. The model is linked to a geographic informationsystem (GIS), allowing model outputs, such as the environmental impacts of site-specific best managementpractices, to be identified in a spatially explicit manner. The model has been tested in New Zealand in anarea of pastoral land use. Advantages of this risk identification model include: utilising

关键词： land-use planning soil quality resilience resistance sustainableagriculture

emission colour tuning in KLnF_(4):Yb^(3+),er^(3+)/Ho^(3+)phosphor

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Journal of Rare earths 2024年第1期42卷 57-65,I0002页

作者： Janani K Gayathri e Vijayatha V Ramasubramanian S Thiyagarajan p Department of Science and Humanities Nehru Institute of TechnologyKaliapuramThirumalayampalayamCoimbatoreIndia Department of Sciences Amrita School of Physical SciencesAmrita Vishwa VidyapeethamCoimbatoreIndia Department of physics Anna UniversityChennaiIndia

KLnF_(4):Yb^(3+),er^(3+)/Ho^(3+)(Ln=Y,Yb,Gd)phosphors were prepared by solid-state reaction *** each of the Yb^(3+)/er^(3+)and Yb^(3+)/Ho^(3+)co-doped phosphors independently,phase confirmation and morphological examination were accomplished using the X-ray diffraction technique and scanning electron microscope analysis.X-ray photoelectron spectroscopy analysis shows the charge state and existence of lanthanides and *** luminescence emissions of green and red colour were detected for the synthesized *** changes in the upconverted emission intensities and colour output pertaining to the change of the lanthanide host matrix along with dopants were investigated for the prepared *** the upconversion luminescence,erbium-doped samples exhibit a predominance of red emission while holmium-doped samples display a prevalence of green *** rare-earth er/Ho doped KYbF4shows strong red emission compared to other ***_(4):Yb,er/Ho exhibits relatively significant green upconve rsion emissions,while Yb,er-doped KGdF_(4)host displays a 10-fold increase in green/red emission ratio with an increase in the input power of 20-780 *** photoluminescence studies and decay curve analysis were carried out using UV light excitation for the developed phosphors.A higher lifetime of 2.2 ms was measured for the downshifting red emission in the Ho doped KYbF_(4)*** study suggests a potential for colour tunability in the upconversion and downshifting emissions through host modifications to the fluoride phosphor.

关键词： Rare earths energy transfer upconversion Downshifting Colour coordinates

effect of local environment in resonant domains of polydisperse plasmonic nanoparticle aggregates on optodynamic processes in pulsed laser fields

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Chinese physics B 2015年第4期24卷 467-474页

作者： A.e.ershov A.p.Gavrilyuk S.V.Karpov p.N.Semina L.V.Kirensky Institute of physics Russian Academy of Sciences Institute of Computational Modeling Russian Academy of Sciences Siberian State Aerospace University Siberian Federal University

Interactions of pulsed laser radiation with resonance domains of multiparticle colloidal aggregates having an increasingly complex local environment are studied via an optodynamic model. The model is applied to the simplest configurations, such as single particles, dimers, and trimers consisting of mono- and polydisperse Ag nanoparticles. We analyze how the local environment and the associated local feld enhancement by surrounding particles affect the optodynamic processes in domains, including their photomodification and optical properties.

关键词： nanoparticle surface plasmon colloid aggregate optodynarnics

Sentiment Drift Detection and Analysis in Real Time Twitter Data Streams

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Computer Systems Science & engineering 2023年第6期45卷 3231-3246页

作者： e.Susi A.p.Shanthi Department of Computer Science&engineering Anna UniversityChennai600025Tamil NaduIndia

Handling sentiment drifts in real time twitter data streams are a challen-ging task while performing sentiment classifications,because of the changes that occur in the sentiments of twitter users,with respect to *** growing volume of tweets with sentiment drifts has led to the need for devising an adaptive approach to detect and handle this drift in real *** work proposes an adap-tive learning algorithm-based framework,Twitter Sentiment Drift Analysis-Bidir-ectional encoder Representations from Transformers(TSDA-BeRT),which introduces a sentiment drift measure to detect drifts and a domain impact score to adaptively retrain the classification model with domain relevant data in real *** framework also works on static data by converting them to data streams using the Kafka *** experiments conducted on real time and simulated tweets of sports,health care andfinancial topics show that the proposed system is able to detect sentiment drifts and maintain the performance of the classification model,with accuracies of 91%,87%and 90%,*** the results have been provided only for a few topics,as a proof of concept,this framework can be applied to detect sentiment drifts and perform sentiment classification on real time data streams of any topic.

关键词： Sentiment drift sentiment classification big data BeRT real time data streams twitter

Low power Laser Surfi-Sculpt

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稀有金属材料与工程 2011年第S4期40卷 147-150页

作者： J.e.Blackburn p.A.Hilton Laser and Sheet processes Group TWI LtdCambridgeCB21 6ALUnited Kingdom

The functional properties of materials can be enhanced using surface features,for instance;to improve the thermal properties of heat *** development of the laser Surfi-Sculpt process over the past decade has resulted in a technology capable of producing a wide variety of features in metallic ***,the potential for producing similar features in polymeric and ceramic substrates also *** the potential for utilizing high power focused laser beams to produce surface features using this process has been *** paper details the results of recent trials performed with a 200 Yb-fibre laser and a galvanometer driven beam scanner for producing surface features using the Surfi-Sculpt process.A compact,cheap,easily robotically automated,laser Surfi-Sculpt machine,being able to operate at atmospheric pressure may have potential in a range of industry sectors.

关键词： laser surfacing Yb-fibre surfi-sculpt

Negative consequences of positive feedbacks in US wild-fire management

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Forest ecosystems 2015年第2期2卷 57-66页

作者： David e Calkin Matthew p Thompson Mark A Finney Forestry Sciences Laboratory US Forest Service Rocky Mountain Research Station Fire Sciences Laboratory US Forest Service Rocky Mountain Research Station

Over the last two decades wildfire activity, damage, and management cost within the US have increased substantially. These increases have been associated with a number of factors including climate change and fuel accumulation due to a century of active fire suppression. The increased fire activity has occurred during a time of significant ex-urban development of the Wildland Urban Interface （WUI） along with increased demand on water resources originating on forested landscapes. These increased demands have put substantial pressure on federal agencies charged with wildfire management to continue and expand the century old policy of aggressive wildfire suppression. However, aggressive wildfire suppression is one of the major factors that drive the increased extent, intensity, and damage associated with the small number of large wildfires that are unable to be suppressed. In this paper we discuss the positive feedback loops that lead to demands for increasing suppression response while simultaneously increasing wildfire risk in the future. Despite a wealth of scientific research that demonstrates the limitations of the current management paradigm pressure to maintain the existing system are well entrenched and driven by the existing social systems that have evolved under our current management practice. Interestingly, US federal wildland fire policy provides considerable discretion for managers to pursue a range of management objectives however, societal expectations and existing management incentive structures result in policy implementation that is straining the resilience of fire adapted ecosystems and the communities that reside in and adjacent to them.

关键词： Wildfire suppression Wildfire paradox Wildland urban interface Resilience

Notes from the Underground:Receptor-Like Kinases in Arabidopsis Root Development

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Journal of Integrative plant Biology 2013年第12期55卷 1224-1237页

作者： Michael p.Wierzba Frans e.Tax Department of Molecular and Cellular Biology University of Arizona School of plant Sciences University of Arizona

During plant development, the frequency and context of cell division must be controlled, and cells must differentiate properly to perform their mature functions. In addition, stem cell niches need to be maintained as a reservoir for new cells. All of these processes require intercellular signaling, whether it is a cell relaying its position to other cells, or more mature cells signaling to the stem cell niche to regulate the rate of growth. Receptor-like kinases have emerged as a major component in these diverse roles, especially within the Arabidopsis root. In this review, the functions of receptor-like kinase signaling in regulating Arabidopsis root development will be examined in theareas of root apical meristem maintenance, regulation of epidermal cell fate, lateral root development and vascular differentiation.

关键词： Lateral root development receptor-like kinases root apical meristem root epidermal patterning vascular development.

Digestive retention times for Allen’s swamp monkey and L’Hoest’s monkey: data with implications for the evolution of cercopithecine digestive strategy

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Integrative Zoology 2012年第2期7卷 183-191页

作者： Kevin p.BLAINe Joanna e.LAMBeRT Department of Anesthesia Stanford University Medical CenterStanfordCaliforniaUSA Department of ecological Anthropology University of Texas at San AntonioSan AntonioTexasUSA

primates access energy from plant fiber via bacterial fermentation in either a modified forestomach(‘foregut’),a caecocolic(‘hindgut’)chamber of the large intestine,or *** digestive retention times allow for more complete fermentation;as such,primates that consume an herbivorous diet high in fiber are expected to have both relatively and absolutely longer retention times than those mammals that rely on more readily digestible plant foods,such as *** used particulate markers to measure the digestive retention times of captive Allen’s swamp monkeys[Allenopithecus nigroviridis(pocock,1907)](n=3)and L’Hoest’s monkey(Cercopithecus lhoesti ***,1899)(n=2).Results indicate mean retention times of 23.2-29.4 h and 23.2-24.0 h for *** and ***,*** from this study,in combination with previously published data on digestive retention times in other primate species,indicate that cercopithecines differ from other primate taxa by having lengthier retention times that can be predicted by body mass *** data are consistent with the hypothesis that relatively lengthy retention times are a primitive trait for Cercopithecinae.

关键词： Cercopithecinae digestive retention time evolution of diet fermentation plant fiber

Vegetation and Topographic Control on Spatial Variability of Soil Organic Carbon

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pedosphere 2013年第1期23卷 48-58页

作者： I.OUeSLATI p.ALLAMANO e.BONIFACIO p.CLApS DITIC Politecnico di Torino DIVApRA Università di Torino

Soil organic carbon (SOC) is one of the most important parameters affecting the hydraulic characteristics of natural soils. Despite being rather easy to measure, SOC is known to be highly variable in space. In this study, vegetation, climate, and morphology factors were used to reproduce the spatial distribution of SOC in the mineral horizons of forest and grassland areas in north-western Italy and the feasibility of the approach was evaluated. When the overall sample (114 samples) was analyzed, average annual rainfall and elevation were significant descriptors of the SOC variability. However, a large part of the variability remains unexplained. Two stratification criteria were then adopted, based on vegetation and topographic properties. We obtained an improvement of the quality of the estimates, particularly for grasslands and forests in the absence of local curvatures. These results indicate that the spatial variability of soil organic matter is scarcely reproducible at the regional scale, unless an a-priori reduction of the heterogeneity is applied. A discussion on the feasibility of applying stratification criteria to deal with heterogeneous samples closes the paper.

关键词： climate factor natural soils regression analysis SOC