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Understanding plant drought resistance in a Mediterranean coastal sand dune ecosystem:differences between native and exotic invasive species

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Journal of Plant Ecology 2018年第1期11卷 26-38页

作者： Cristina Antunes Ana Júlia Pereira Patrícia Fernandes Margarida Ramos lia Ascensão Otília Correia Cristina Máguas Centre for Ecology Evolution and Environmental ChangesFaculdade de CiênciasUniversidade de LisboaCampo Grande1749-016 LisboaPortugal PPG-Ecologia Instituto de BiologiaCP 6109Universidade Estadual de Campinas-UNICAMP13083-970 CampinasSão PauloBrazil SPBotânica-Botanical Society of Portugal Travessa do Jardim 3A-dos-Potes2615-018 Alverca do RibatejoPortugal CESAM-Centre for Environmental and Marine Studies Faculdade de Ciências-CBVUniversidade de Lisboa1749-016 LisboaPortugal

Aims Mediterranean coastal dunes are habitats of great conservation interest,with a distinctive and rich *** the last century,Acacia spp.,native from Australia,have been introduced in Portugal,with the objective of stabilizing sand dunes,and since have become dominant in numerous sand dune *** invasion process led to the reduction of native plant species richness,changed soil characteristics and modified habitat’s microclimatic *** aim of this research was to typify and compare,in Mediterranean sand dune ecosystems,the ecophysiological responses to drought of Helichrysum italicum and Corema album,two native species,and Acacia longifolia,an exotic invasive *** addressed the following specific objectives:(i)to com-pare water relations and water use efficiencies,(ii)to evaluate water stress,(iii)to assess water use strategies and water sources used by plants and(iv)to evaluate the morphological adaptations at leaf and phyllode *** In order to obtain an integrative view of ecophysiological patterns,water relations and performance measuring methods have been applied:predawn(ψPD)and midday(ψMD)water potential,chloro-phyll a fluorescence,oxygen isotopic composition of xylem,rain and groundwater(δ18O)and leaf carbon isotopic discrimination(Δ13C).The leaf characteristics of the three species,as well as the histochemistry of non-glandular trichome cell walls,were also studied to identify morpho-traits related to drought *** Findings The results support our initial hypothesis:although *** clearly possesses a degree of resistance to water stress,such ability is provided by a different water strategy,when compared to native *** relied on morphological adaptations to restrict water loss,whereas the invasive species adjusted the water uptake as a way to balance their limited ability of restricting water *** corroborate that woody native species(i)have a conservative water-saving strategy an

关键词： ecophysiology water use strategy leaf morphology Acacia longifolia Corema album Helichrysum italicum

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Predicting the aquatic risk of realistic pesticide mixtures to species assemblages in Portuguese river basins

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Journal of Environmental Sciences 2015年第5期27卷 12-20页

作者： Emília Silva Michiel A.Daam Maria José Cerejeira Centro de Engenharia dos Biossistemas (CEER) Instituto Superior de Agronomia (ISA) University of Lisbon (UL) Tapada da Ajuda1349-017 Lisbon Portugal

Although pesticide regulatory tools are mainly based on individual substances, aquatic ecosystems are usually exposed to multiple pesticides from their use on the variety of crops within the catchment of a river. This study estimated the impact of measured pesticide mixtures in surface waters from 2002 and 2008 within three important Portuguese river basins（＇Mondego＇, ＇Sado＇ and ＇Tejo＇） on primary producers, arthropods and fish by toxic pressure calculation. Species sensitivity distributions（SSDs）, in combination with mixture toxicity models, were applied. Considering the differences in the responses of the taxonomic groups as well as in the pesticide exposures that these organisms experience, variable acute multi-substance potentially affected fractions（ms PAFs） were obtained. The median msP AF for primary producers and arthropods in surface waters of all river basins exceeded 5%, the cut-off value used in the prospective SSD approach for deriving individual environmental quality standards. A ranking procedure identified various photosystem II inhibiting herbicides, with oxadiazon having the relatively largest toxic effects on primary producers, while the organophosphorus insecticides, chlorfenvinphos and chlorpyrifos, and the organochloride endosulfan had the largest effects on arthropods and fish, respectively. These results ensure compliance with European legislation with regard to ecological risk assessment and management of pesticides in surface waters.

关键词： Pesticides Mixtures Risk assessment Multi-substance potentially affected fraction Surface waters

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Axonal growth inhibitors and their receptors in spinal cord injury:from biology to clinical translation

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Neural Regeneration Research 2023年第12期18卷 2573-2581页

作者： Sílvia Sousa Chambel Célia Duarte Cruz Experimental Biology Unit Department of BiomedicineFaculty of Medicine of PortoUniversity of PortoPortoPortugal Translational NeuroUrology Instituto de Investigação e Inovação em Saúde-i3S and IBMCUniversidade do PortoPortoPortugal

Axonal growth inhibitors are released during traumatic injuries to the adult mammalian central nervous system, including after spinal cord injury. These molecules accumulate at the injury site and form a highly inhibitory environment for axonal regeneration. Among these inhibitory molecules, myelinassociated inhibitors, including neurite outgrowth inhibitor A, oligodendrocyte myelin glycoprotein, myelin-associated glycoprotein, chondroitin sulfate proteoglycans and repulsive guidance molecule A are of particular importance. Due to their inhibitory nature, they represent exciting molecular targets to study axonal inhibition and regeneration after central injuries. These molecules are mainly produced by neurons, oligodendrocytes, and astrocytes within the scar and in its immediate vicinity. They exert their effects by binding to specific receptors, localized in the membranes of neurons. Receptors for these inhibitory cues include Nogo receptor 1, leucine-rich repeat, and Ig domain containing 1 and p75 neurotrophin receptor/tumor necrosis factor receptor superfamily member 19(that form a receptor complex that binds all myelin-associated inhibitors), and also paired immunoglobulin-like receptor B. Chondroitin sulfate proteoglycans and repulsive guidance molecule A bind to Nogo receptor 1, Nogo receptor 3, receptor protein tyrosine phosphatase σ and leucocyte common antigen related phosphatase, and neogenin, respectively. Once activated, these receptors initiate downstream signaling pathways, the most common amongst them being the Rho A/ROCK signaling pathway. These signaling cascades result in actin depolymerization, neurite outgrowth inhibition, and failure to regenerate after spinal cord injury. Currently, there are no approved pharmacological treatments to overcome spinal cord injuries other than physical rehabilitation and management of the array of symptoms brought on by spinal cord injuries. However, several novel therapies aiming to modulate these inhibitory prot

关键词： chondroitin sulphate proteoglycans collapsin response mediator protein 2 inhibitory molecules leucine-rich repeat and Ig domain containing 1 leucocyte common antigen related myelin-associated glycoprotein neurite outgrowth inhibitor A Nogo receptor 1 Nogo receptor 3 oligodendrocyte myelin glycoprotein p75 neurotrophin receptor Plexin A2 Ras homolog family member A/Rho-associated protein kinase receptor protein tyrosine phosphataseσ repulsive guidance molecule A spinal cord injury tumour necrosis factor receptor superfamily member 19

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Hard carbon derived from coconut shells,walnut shells,and corn silk biomass waste exhibiting high capacity for Na-ion batteries

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Journal of Energy Chemistry 2021年第7期30卷 207-218页

作者： Cristina Nita Biao Zhang Joseph Dentzer Camélia Matei Ghimbeu Universitéde Haute-Alsace Institut de Science des Matériaux de Mulhouse(IS2M)CNRS UMR 7361F-68100 MulhouseFrance Universitéde Strasbourg F-67081 StrasbourgFrance Center for Advanced Laser Technologies(CETAL) National Institute for LasersPlasma and Radiation PhysicsAtomistilor 409 bisRO-77125 MagureleRomania Department of Applied Physics The Hong Kong Polytechnic UniversityKowloonHong KongChina Réseau sur le Stockage Electrochimique de l’Energie(RS2E) CNRS FR345933 Rue Saint Leu80039 Amiens CedexFrance

In recent years,hard carbon materials have gained significant interest as anode materials for Na-ion *** waste is considered one of the most interesting,renewable,available,and cost-effective precursor to obtain hard carbon(HC);however,HC properties must be finely tuned to achieve performance comparable to those provided by Li-ion *** this work,three biomass wastes(coconut shells,walnut shells,and corn silk) were evaluated as potential precursors for HC preparation involving a pyrolysis process and subsequent acid washing to remove the inorganic *** obtained materials exhibited low and similar specific surface areas(<10 m^(2)·g^(-1)), but they presented different structures and surface *** walnut shell HC possessed a lower amount of inorganic impurities and oxygen-based functional groups compared to the coconut shell and corn silk HCs,leading to higher initial coulombic efficiency(iCE).The structural organization was higher in the case of the walnut shell HC,while the corn silk HC revealed a heterogeneous structure combining both highly disordered carbon and localized graphitized *** HCs delivered high initial reversible capacities between 293 and 315 mAh g^(-1) at 50 mA g^(-1) current rate,which remained rather stable during long-term *** best capacity(293 mAh g^(-1) after 100 charge/discharge cycles) and highest capacity retention(93%) was achieved in walnut HCs in half-cells,which could be associated with its higher sp2 C content,better organized structure,and fewer *** "adsorption-insertion" Na storage mechanism is suggested based on several *** walnut HCs exhibited an attractive energy density of 279 Wh/kg when tested in full cells.

关键词： Biomass Pyrolysis Hard carbon Anode Na-ion batteries Energy storage

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Influence of location of large-scale asperity on shear strength of concrete-rock interface under eccentric load

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第3期12卷 449-460页

作者： Dipen Bista Gabriel Sas Fredrik Johansson Leif lia SINTEF Narvik As Narvik8517Norway Norwegian University of Science and Technology(NTNU) Trondheim7491Norway Royal Institute of Technology(KTH) Stockholm10044Sweden

The location and geometry of large-scale asperity present at the foundation of concrete gravity dams and buttress dams affect the shear resistance of the concrete-rock ***,the parameters describing the frictional resistance of the interface usually do not account for these *** could result in an underestimate of the peak shear stre ngth,which leads to significantly conservative design for new dams or unnecessary stability enhancing measures for existing *** aim of this work was to investigate the effect of the location of first-order asperity on the peak shear strength of a concrete-rock interface under eccentric load and the model discrepancy associated with the commonly used rigid body methods for calculating the factor of safety(FS)against *** this,a series of direct and eccentric shear tests under constant normal load(CNL)was carried out on concrete-rock *** peak shear strengths measured in the tests were compared in terms of asperity location and with the predicted values from analytical rigid body *** results showed that the large-scale asperity under eccentric load significantly affected the peak shear ***,unlike the conventional assumption of sliding or shear failure of an asperity in direct shear,under the effect of eccentric shear load,a tensile failure in the rock or in the concrete could occur,resulting in a lower shear strength compared with that of direct shear *** results could have important implications for assessment of the FS against sliding failure in the concrete-rock interface.

关键词： Shear strength Concrete-rock interface Asperity location Eccentric load Model discrepancy Dam foundation

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Numerical Solution for a Non-Fickian Diffusion in a Periodic Potential

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Communications in Computational Physics 2013年第2期13卷 502-525页

作者： Adérito Araújo Amal K.Das Cidália Neves Ercília Sousa CMUC Department of MathematicsUniversity of Coimbra3001-454 CoimbraPortugal Department of Physics DalhousieUniversityHalifaxNova Scotia B3H3J5Canada ISCAC Polytechnic Institute of Coimbra3040-316 CoimbraPortugal

Numerical solutions of a non-Fickian diffusion equation belonging to a hyperbolic type are presented in one space *** Brownian particle modelled by this diffusion equation is subjected to a symmetric periodic potential whose spatial shape can be varied by a single *** consider a numerical method which consists of applying Laplace transform in time;we then obtain an elliptic diffusion equation which is discretized using a finite difference *** analyze some aspects of the convergence of the *** results for particle density,flux and mean-square-displacement(covering both inertial and diffusive regimes)are presented.

关键词： Numerical methods Laplace transform telegraph equation periodic potential non-Fickian diffusion

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Nanoparticles as delivery vehicles for antiviral therapeutic drugs

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Engineered Regeneration 2021年第1期2卷 31-46页

作者： Alexander Maus lia Strait Donghui Zhu Department of Biomedical Engineering Stony Brook UniversityUnited States

With the ongoing COVID-19 pandemic still escalating,many researchers are turning to nanotechnology as a method of treatment not only for this pandemic,but in preparation for the pandemics of the *** both a wide variety of biomaterials at their disposal and the recent rise of nanotechnology,scientists now have the means to release and distribute therapeutic drugs in a variety of *** a variety permits medical professionals the ability to choose biomaterials and methods that would provide the best release and treatment methodologies for the viral ailment they are attempting to *** integrative review discusses context of previous pandemics,viral pathogenesis,issues associated with the current state of antiviral delivery systems,numerous biomaterials used for this purpose,and further information regarding the ongoing global COVID-19 pandemic.

关键词： Nanotechnology COVID-19 Antiviral Drug selivery

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Building segmentation and outline extraction from UAV image-derived point clouds by a line growing algorithm

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International Journal of Digital Earth 2017年第11期10卷 1077-1097页

作者： Yucheng Dai Jianhua Gong Yi lia Quanlong Feng State Key Laboratory of Remote Sensing Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijingPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China Beijing Piesat Information Technology Co. Ltd.BeijingPeople’s Republic of China

This paper presents an approach to process raw unmanned aircraft vehicle(UAV)image-derived point clouds for automatically detecting,segmenting and regularizing buildings of complex urban *** regularizing,we mean the extraction of the building footprints with precise position and *** the first step,vegetation points were extracted using a support vector machine(SVM)classifier based on vegetation indexes calculated from color information,then the traditional hierarchical stripping classification method was applied to classify and segment individual *** the second step,we first determined the building boundary points with a modified convex hull ***,we further segmented these points such that each point was assigned to a fitting line using a line growing ***,two mutually perpendicular directions of each individual building were determined through a W-k-means clustering algorithm which used the slop information and principal direction ***,the building edges were regularized to form the final building *** and quantitative measures were used to evaluate the performance of the proposed approach by comparing the digitized results from ortho images.

关键词： Line growing algorithm regularization UAV image-derived point cloud vegetation index W-k-means clustering algorithm

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L-proline feeding for augmented freeze tolerance of Camponotus japonicus Mayr

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Science Bulletin 2019年第23期64卷 1795-1804页

作者： Mengjia Dou Yazhou Li Ziqiao Sun Lei lia Wei Rao C4S Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beijing Engineering Research Center of Sustainable Energy and Buildings Beijing University of Civil Engineering and ArchitectureBeijing 100044China School of Future Technology University of Chinese Academy of SciencesBeijing 100049China Beijing Key Laboratory of Cryo-Biomedical Engineering Beijing 100190China

The successful cryopreservation of organs is a strong and widespread demand around the world but faces great challenges. The mechanisms of cold tolerance of organisms in nature inspirit researchers to find new solutions for these challenges. Especially, the thermal, mechanical, biological and biophysical changes during the regulation of freezing tolerance process should be studied and coordinated to improve the cryopreservation technique and quality of complex organs. Here the cold tolerance of the Japanese carpenter ants, Camponotus japonicus Mayr, was greatly improved by using optimal protocols and feeding on L-proline-augmented diets for 5 days. When cooling to -27.66 ℃, the survival rate of frozen ants increased from 37.50% ± 1.73% to 83.88% ± 3.67%. Profiling of metabolites identified the concentration of whole-body L-proline of ants increased from 1.78 to 4.64 ng g-1 after 5-day feeding. High Lproline level, together with a low rate of osmotically active water and osmotically inactive water facilitated the prevention of cryoinjury. More importantly, gene analysis showed that the expression of ribosome genes was significantly up-regulated and played an important role in manipulating freezing tolerance. To the best of our knowledge, this is the first study to link genetic variation to the enhancement of ants’ cold tolerance by feeding exogenous cryoprotective compound. It is worth noting that the findings provide the theoretical and technical foundation for the cryopreservation of more complex tissues,organs, and living organisms.

关键词： L-proline Cryopreservation Freeze tolerance Metabolomics Gene expression

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INTRINSIC FLUORESCENCE CHANGES IN NERVE TERMINALS,EVOKED BY ACTION POTENTIALS,ARE MODULATED BY KREBS CYCLE SUBSTRATES

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Journal of Innovative Optical Health Sciences 2011年第2期4卷 209-214页

作者： PAUL KOSTERIN ANA lia OBAID BRIAN M.SALZBERG Department of Neuroscience University of Pennsylvania School of Medicine Philadelphia PA 19104USA Department of Physiology University of Pennsylvania School of Medicine Philadelphia PA 19104USA

Electrical stimulation of the mammalian neurohypophysial infundibular stalk evokes the entry of Nat and Ca^(2+) into the neurosecretory terminals during the action *** events,in turn,increase intracellular Ca^(2+) and activate NaK-and Ca-ATPases,prompting the mitochondria to increase oxidative phosphorylation which can be monitored by recording the changes in FAD and *** paper reflects our efforts to determine whether or not modulating the capacity of mitochondria to produce ATP,by changing the concentrations of two important substrates of the Krebs cycle of the nerve terminal mitochondria,pyruvate and glucose,has an effect on the intrinsicfluorescence changes triggered by action potential stimulation.

关键词： Fluorescence FAD NADH action potential metabolism

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