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Stipa tenacissima Does not Affect the Foliar δ^(13)C and δ^(15)N of Introduced Shrub Seedlings in a Mediterranean Semi-arid Steppe

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Journal of Integrative Plant Biology 2006年第8期48卷 897-905页

作者： fernando T.Maestre Susana Bautista Jordi Cortina Departamento de Ecologia Universidad de AlicanteApartado de correos 9903080 AlicanteSpain Department of Biology Duke UniversityPhytotron BuildingScience DriveBox 90340DurhamNorth Carolina 27708-0340USA Centro de Estudios Ambientales del Mediterraneo C/ Charles Darwin 1446980 PaternaSpain

Recent studies have shown that the tussock grass Stipa tenacissima L. facilitates the establishment of late-successional shrubs, in what constitutes the first documented case of facilitation of woody plants by grasses. With the aim of increasing our knowledge of this interaction, in the present study we investigated the effects of S. tenacissima on the foliar δ13C, δ15N, nitrogen concentration, and carbon ： nitrogen ratio of introduced seedlings of Pistacia lentiscus L., Quercus coccifera L., and Medicago arborea L. in a semi-arid Mediterranean steppe. Six months after planting, the values of δ13C ranged between -26.9‰ and -29.6‰, whereas those of δ15N ranged between -1.9‰ and 2.7‰. The foliar C ： N ratio ranged between 10.7 and 53.5, and the nitrogen concentration ranged between 1.0% and 4.4%. We found no significant effect of the microsite provided by S. tenacissima on these variables in any of the species evaluated. The values of δ13C were negatively correlated with predawn water potentials in M. arborea and were positively correlated with relative growth rate in Q. coccifera. The values of δ15N were positively correlated with the biomass allocation to roots in the latter species. The present results suggest that the modification of environmental conditions in the are surrounding S. tenacissima was not strong enough to modify the foliar isotopic and nitrogen concentration of shrubs during the early stages after planting.

关键词： facilitation Medicago arborea Pistacia lentiscus Quercus coccifera stable isotopes steppe Stipa tenacissima.

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Heritage Today: The Art of Transforming What We Received from the Past

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Built Heritage 2017年第3期1卷 60-68页

作者： fernando Perez Oyarzun Faculty of Architecture Design and Urban StudiesPontificia Universidad Católica de ChileSantiagoChile

The paper aims at highlighting the new reality of urban and architectural *** maintains that the current public claim for heritage protection radically diverges from the original endeavour of protecting national *** significant expansion of heritage goods and the involvement of citizen movements in the decisions about them are two of the most visible aspects of this *** paper suggests that a renovated idea of heritage is currently *** should take into consideration aspects such as its economic value and its connection to the quality of daily *** that urban preservation has turned to be part of planning,the paper foregrounds some of the problems of keeping it as a separate legal and cultural *** is exemplified by Latin American reality and some specific cases from *** it highlights the positive role of transformation and adaptation in the preservation of heritage.

关键词： heritage urban heritage heritage challenges heritage transformation Latin American heritage

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Geo-vegetation Mapping and Soil Geochemical Characteristics of the Indikolapelessa Serpentinite Outcrop,Southern Sri Lanka

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Journal of Earth Science 2014年第1期25卷 152-168页

作者： Tilak Hewawasam G W A R fernando Danushka Priyashantha Department of Natural Resources Sabaragamuwa University of Sri Lanka Department of Geography University of Peradeniya Department of Physics Open University of Sri Lanka

The serpentinite blocks of Indikolapelessa, located along an identified litho-tectonic boundary between the Highland Complex （HC） and the Vijayan Complex （VC） of Sri Lanka, have undergone extensive lateralization with metal enrichment. Characteristic serpentinite vegetation with some endemic species was recognized in the soils and supergene deposits develop on serpentinite lithology. This type of geological and ecological relationship forms vegetation covers on serpentinite lithologies which are sharply demarcated from the surrounding metamorphic terrains. The aforesaid ＂geo-ecological phenomenon＂ can be used as a tool for geo-vegetation mapping in ultramafic terrains to trace the geological boundaries in landscapes where rock outcrops are virtually absent. We success- fully applied the concept of geo-vegetation mapping in order to demarcate the boundary of underlain serpentinite rocks from surrounding non-serpentinite metamorphic rocks （e.g. granitic gneiss）. The hypothesis was supported by the geochemical variations of soils/supergene deposits found at serpen- tinite and non-serpentinite sites, especially immobile elements and some trace elements. Based on whole rock chemistry and soil chemical data obtained, we suggest that the Indikolapelessa serpentinite outcrop, together with the other four serpentinite outcrops, is more likely to represent the Mg-rich mantle fragments at the time of overthrusting of the two crustal blocks of HC and VC during the Pan- African event.

关键词： serpentinite serpentinite soil geochemistry geo-vegetation ultramafic rock Sri Lanka.

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Pioneering the direct large-scale laser printing of flexible“graphenic silicon”self-standing thin films as ultrahigh-performance lithium-ion battery anodes

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Carbon Energy 2024年第7期6卷 26-40页

作者： Avinash Kothuru Adam Cohen Gil Daffan Yonatan Juhl fernando Patolsky School of Chemistry Faculty of Exact SciencesTel Aviv UniversityTel AvivIsrael Department of Materials Science and Engineering The Iby and Aladar Fleischman Faculty of EngineeringTel Aviv UniversityTel AvivIsrael

Recent technological advancements,such as portable electronics and electric vehicles,have created a pressing need for more efficient energy storage ***-ion batteries(LIBs)have been the preferred choice for these applications,with graphite being the standard anode material due to its ***,graphite falls short of meeting the growing demand for higher energy density,possessing a theoretical capacity that lags *** address this,researchers are actively seeking alternative materials to replace graphite in commercial *** promising avenue involves lithiumalloying materials like silicon and phosphorus,which offer high theoretical ***-silicon composites have emerged as a viable option,showing improved capacity and performance over traditional graphite or pure silicon ***,the existing methods for synthesizing these composites remain complex,energy-intensive,and costly,preventing widespread adoption.A groundbreaking approach is presented here:the use of a laser writing strategy to rapidly transform common organic carbon precursors and silicon blends into efficient“graphenic silicon”composite thin *** films exhibit exceptional structural and energy storage *** resulting three-dimensional porous composite anodes showcase impressive attributes,including ultrahigh silicon content,remarkable cyclic stability(over 4500 cycles with∼40%retention),rapid charging rates(up to 10 A g^(-1)),substantial areal capacity(>5.1 mAh cm^(-2)),and excellent gravimetric capacity(>2400 mAh g^(-1) at 0.2 A g^(-1)).This strategy marks a significant step toward the scalable production of high-performance LIB *** widely available,cost-effective precursors,the laser-printed“graphenic silicon”composites demonstrate unparalleled performance,potentially streamlining anode production while maintaining exceptional *** innovation not only paves the way for advanced LIBs but also sets a precedent for

关键词： 4D printing energy storage fast-charging laser-induced graphene lithium-ion silicon carbon composite anodes

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Developing a two-decadal time-record of rice field maps using Landsat-derived multi-index image collections with a random forest classifier:A Google Earth Engine based approach

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Information Processing in Agriculture 2024年第2期11卷 260-275页

作者： W.Ashane M.fernando I.P.Senanayake Department of Nano Science Technology Wayamba University of Sri LankaKuliyapitiya 60200Sri Lanka Dchoolf Engineing CllegeoEngineeringSience and EnionmentThe UniversyewcastleCallaghanW2Austraia

Historic maps showing the temporal distribution of rice fields are important for precision agriculture,irrigation optimisation,forecasting crop yields,land use management and formulating ***,mapping rice felds using traditional ground surveys is impractical when high cost,time and labour requirements are considered,and the availability of such detailed records is *** satellite remote sensing appears to be a viable solution,conventional segmentation and classification methods with spectral bands are often unable to contrast the distinct characteristics between rice fields and other vegetation *** this end,we explored a novel,Google Earth Engine(GEE)based multiindex random forest(RF)classification approach to map rice fields over two *** images from 2000 to 2020 of two Sri Lankan rice cultivation districts were extracted from GEE and a multi-index RF classification algorithm was applied to distinguish the rice *** results showed above 80%accuracy for both training and validation,when compared against high spatial resolution Google Earth *** essence,multi-index sampling and RF together synergised the compelling classifcation accuracy by effectively capturing vegetation,water(ponding)and soil characteristics unique to the rice felds using a single-click *** maps developed in this study were further compared against the MODIS land cover type product(MCD12Q1)and the corresponding superior statistics on rice fields demonstrated the robustness of the proposed *** work seeking effective index combinations is recommended,and this approach can potentially be extended to other crop analyses elsewhere.

关键词： Google Earth Engine(GEE) Image classification Random forest Mapping rice fields Time series analysis Vegetation index

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Evaluation of effectiveness of polymer coatings in reducing blastinduced deformation of steel plates

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Defence Technology（防务技术） 2021年第6期17卷 1895-1904页

作者： Damith Mohotti P.L.N.fernando Dakshitha Weerasinghe Alex Remennikov School of Engineering and Information Technology The University of New South WalesCanberraACT2600Australia Department of Civil Engineering Faculty of EngineeringGeneral Sir John Kotelawala Defence UniversityRatmalanaSri Lanka School of Civil Engineering Faculty of EngineeringThe University of SydneyDarlingtonNSW2006Australia Centre for Infrastructure Protection and Mining Safety University of WollongongWollongongNSW2522Australia

Incorporating elastomers such as polymers in protective structures to withstand high energetic dynamic loads,has gained significant *** main objective of this study is to investigate the influence of a Polyurea coating towards the blast-induced response in steel *** such,Polyurea coated steel plates were tested under near-field blast loads,produced by the detonation of 1 kg of spherical nitromethane charges,at a standoff distance of 150 *** steel(XLERPLATE 350)and high-strength steel(BIS80)plates with thicknesses of 10 mm were Polyurea coated with thicknesses of 6 mm and 12 mm on either the front(facing the charge)or the back *** deformation profiles were measured using 3D *** simulations were performed using the non-linear finite element code *** strain-dependent behaviour of the steel and Polyurea were represented by Johnson-cook and Money-Rivlin constitutive models,*** numerical models were validated by comparing the plate deflection results obtained from the experiments and were then used in the subsequent parametric study to investigate the optimum thickness of the Polyurea *** results indicate that back face coating contributes towards an approximately 20%reduction in the residual deformation as well as the absence of melting of the Polyurea layer,while the front-face coating can be used a means of providing additional standoff distance to the steel plates.

关键词： Polyurea coating Near-field blast LS-DYNA Plate deformation ALE

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Fire dynamics in Mato Grosso State,Brazil:the relative roles of gross primary productivity

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Big Earth Data 2020年第1期4卷 23-44页

作者： fernando Saragosa Rossi Gustavo Andrede Araujo Santos State University of Mato Grosso(UNEMAT) Mato GrossoSinopBrazil Department of Exact Sciences São Paulo State University(FCAV–UNESP)Via de Acesso Prof.Paulo Donato Castellane s/n14884-900 JaboticabalSão PauloBrazil

The fires and biomass burning are responsible for affect ecosystem processes in a wide range of biomes at regional and global *** Brazil,the state of Mato Grosso is one of the most affected by the occurrence of forest ***,this study aims to quantify the longterm changes in the temporal and spatial patterns of fire occurrence and their effect on gross primary productivity(GPP)in the state of Mato Grosso,Brazil,considering the biomes that compose *** images used in the study were acquired by satellite Terra and Aqua combined in the product MCD64A1.006,a monthly resolution of 500m by the Moderate Resolution Imaging Spectroradiometer(MODIS)sensor,during the period from 01/10/2000 to 12/31/*** MOD17A2 product derived from the MODIS sensor provides the accumulated value of *** points without the presence of burning presented higher values of GPP for all studied *** some points with the presence of burning the GPP even decreased by 44.20%,30.04%and 55.78%for Amazonia,Cerrado,and Pantanal,*** to the results presented here,it is concluded that the burnings negatively impact gross primary production in the biomes of the state of Mato Grosso,Brazil and the dynamics of the burns do not keep up with the intensity of drought *** use of cluster analysis techniques,such as principal component analysis(PCA),is an alternative to bigdata analysis when the objective is to evaluate the presence of forest burning in more than one biome.

关键词： Carbon cycle remote sensing Amazon Cerrado Pantanal

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Scrub typhus:pathophysiology,clinical manifestations and prognosis

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Asian Pacific Journal of Tropical Medicine 2012年第4期5卷 261-264页

作者： Senaka Rajapakse Chaturaka Rodrigo Deepika fernando Department of Clinical Medicine Faculty of Medicine25 Kynsey RoadColombo 8Sri Lanka Department of Parasitology Faculty of Medicine25 Kynsey RoadColombo 8Sri Lanka

Scrub typhus is a zoonosis caused by the pathogen Orientia tsutsugamushi(***). The disease has significant prevalence in eastern and Southeast *** presenting as an acute febrile illness,the diagnosis is often missed because of similarities with oilier tropical febrile *** unusual manifestations are present,and these are described in this review,together with an outline of current knowledge of *** of these unusual clinical manifestations will help the clinician to arrive at an early diagnosis,resulting in early administration of appropriate *** indicators for severe disease have not yet been clearly established.

关键词： Scrub typhus Orientia tsutsugamushi Clinical manifestations

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Chemoprophylaxis in malaria:drugs,evidence of efficacy and costs

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Asian Pacific Journal of Tropical Medicine 2011年第4期4卷 330-336页

作者： Sumadhya Deepika fernando Chaturaka Rodrigo Senaka Rajapakse Department of Parasitology Faculty of Medicine University Medical Unit National Hospital of Sri Lanka Department of Clinical Medicine Faculty of Medicine

This review concentrates on different aspects of malaria chemoprophylaxis,namely drug combinations,resistance,impact of malaria prevention in pregnancy and cost effectiveness. A MEDLINE search was performed for all articles with the key word ’Malaria’ in the title field and ’Prophylaxis’ in any *** search was restricted to articles published in English within the last decade(1999-2009).Data sources included review articles published in core clinical journals,cohort studies,interventional studies,case control studies and cross sectional analyses. The mechanism of action,trial evidence of efficacy,side effects and geographical distribution of resistance is discussed for each prophylactic drug *** of prophylaxis in pregnancy and the cost considerations are discussed under two separate sub topics.

关键词： Malaria Prophylaxis Pregnancy Cost

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A Comprehensive Survey on Fault Diagnosis and Fault Tolerance of DC-DC Converters

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Chinese Journal of Electrical Engineering 2018年第3期4卷 1-12页

作者： fernando Bento Antonio J.Marques Cardoso CISE-Electromechatronic Systems Research Centre Universidade da Beira InteriorCalcada Fonte do LameiroP-6201-001 CovilhaPortugal Department of Electromechanical Engineering Universidade da Beira InteriorCalcada Fonte do LameiroP-6201-001 CovilhaPortugal

DC-DC converters are becoming more commonly used in power conversion solutions for energy management purposes,being employed in an ever-increasing range of DC-based applications,such as LED lighting,electric vehicles,energy storage solutions,and consumer electronics(laptops,smartphones,etc.).In this context,efficiency and reliability are *** research efforts made in improving reliability of DC-DC converters are still quite narrow and ***,DC-DC converters take the shape of an endless number of topologies,with different functionalities and operation principles,thus complicating the task of improving reliability of all forms of DC-DC ***,compiling the information about the main failure modes,corresponding fault diagnostic algorithms and fault tolerance strategies developed so far,in a single document,becomes increasingly ***,this paper presents an up-to-date review of the recent achievements attained regarding the improvement of availability and reliability of DC-DC converters.

关键词： DC-DC converters fault diagnosis fault tolerance reliability

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