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Developing knn forest data imputation for Catalonia

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Journal of Forestry Research 2024年第4期35卷 142-155页

作者： Timo Pukkala núria Aquilué Ariadna Just Jordi Corbera Antoni trasobares Forest Science and Technology Centre of Catalonia(CTFC) Crta.de St.Llorençde MorunysKm 225280 SolsonaSpain Cartographic and Geological institute of Catalonia(iCGC) 08038 BarcelonaSpain

the combined use of LiDAR(Light Detection And Ranging)scanning and field inventories can provide spatially continuous wall-to-wall information on forest *** information can be used in many ways in forest mapping,scenario analyses,and forest manage-ment *** study aimed to find the optimal way to obtain continuous forest data for Catalonia when using knn imputation(knn stands for“k nearest neighbors”).in this method,data are imputed to a certain location from k field-measured sample plots,which are the most similar to the location in terms of LiDAR metrics and topographic *** multidimensional Euclidean distance was used as the similarity *** study tested two different methods to optimize the distance *** first method optimized,in the first step,the set of LiDAR and topographic variables used in the measure,as well as the transformations of these *** weights of the selected variables were optimized in the second *** other method optimized the variable set as well as their transformations and weights in one single *** two-step method that first finds the variables and their transfor-mations and subsequently optimizes their weights resulted in the best imputation *** the study area,the use of three to five nearest neighbors was *** and latitude turned out to be the most important variables when assessing the similarity of two locations of Catalan forests in the context of knn data *** optimal distance measure always included both LiDAR metrics and topographic *** study showed that the optimal similarity measure may be different for different ***,it was suggested that knn data imputation should always be started with the optimization of the measure that is used to select the k nearest neighbors.

关键词： Forest inventory Differential evolution Simulated annealing LiDAR

Simultaneous removal of critical rare earth elements and chalcogen oxyanions by anaerobic granular sludge

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Rare Metals 2024年第9期43卷 4595-4611页

作者： Chiara Belloni Mohanakrishnan Logan Stefano Papirio Piet n.L.Lens University of Galway Department of Civil Architectural and Environmental EngineeringUniversity of Naples Federico II

Conventional mining of economically and strategically important critical rare earth elements(REEs)(such as neodymium, lanthanum and dysprosium), and chalcogens(such as selenium and tellurium) are associated with a huge economic and environmental cost. therefore,the need to recover REEs as well as chalcogens from different waste streams including wastewaters is becoming urgent. Batch assays on synthetic chalcogen/REE-laden wastewater showed that the presence of REEs significantly improved the tellurite removal rate(> 80%) and enhanced selenate removal by 66% ± 10%. three 3.9 L continuous upflow anaerobic granular sludge bed(UASB) reactors were operated at a hydraulic retention time of 24 h and30 °C. Selenate reduction was achieved with a removal efficiency of ～ 98% with an influent p h of 4.0 for more than 28 days. the effect of REEs on tellurite removal in the UASB bioreactor could not be clearly established since a soluble tellurium removal efficiency of more than 98%was observed already before the addition of REEs at elevated tellurite concentrations. the complete REE removal in both batch assays and UASB reactors at higher ph (7.0 ± 0.5) was attributed to precipitation, whereas chalcogen oxyanions removal was due to microbial reduction. however, at acidic p h, biosorption was responsible for REE's removal, and the Se-enriched sludge exhibited a superior REE's removal efficiency than the non-enriched and Te-enriched sludge.

关键词： Adsorption Bioreduction Rare earth elements Selenium Tellurium

Role of marine natural products in the development of antiviral agents against SARS‑Cov‑2:potential and prospects

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Marine Life Science & Technology 2024年第2期6卷 280-297页

作者： D.P.nagahawatta n.M.Liyanage thilina U.Jayawardena h.h.A.C.K.Jayawardhana Seong‑hun Jeong hyung‑Jun Kwon You‑Jin Jeon Department of Marine Life Sciences Jeju National UniversityJeju 690-756Republic of Korea Department of Chemistry Biochemistry and PhysicsUniversitédu QuébecàTrois-RivièresTrois-RivièresQC G8Z 4M3Canada Marine Science institute Jeju National UniversityJeju 63333Republic of Korea Functional Biomaterial Research Center Korea Research Institute of Bioscience and BiotechnologyJeongeup-siRepublic of Korea

A novel coronavirus,known as severe acute respiratory syndrome coronavirus 2(SARS-Cov-2),has surfaced and caused global concern owing to its ***-Cov-2 is the causative agent of coronavirus disease 2019;however,it was only discovered at the end of the year and was considered a pandemic by the World health ***,the develop-ment of novel potent inhibitors against SARS-Cov-2 and future outbreaks is urgently *** naturally occurring bioactive substances have been studied in the clinical setting for diverse *** intricate infection and replication mechanism of SARS-Cov-2 offers diverse therapeutic drug targets for developing antiviral medicines by employing natural products that are safer than synthetic *** natural products(MnPs)have received increased attention in the development of novel drugs owing to their high diversity and ***,this review article investigates the infection and replication mechanisms,including the function of the SARS-Cov-2 genome and ***,we highlighted anti-SARS-Cov-2 therapeutic intervention efforts utilizing MnPs and predicted SARS-Cov-2 inhibitor design.

关键词： SARS-Cov-2 Marine natural products Drug targets inhibitors

Greatly enhanced corrosion/wear resistances of epoxy coating for Mg alloy through a synergistic effect between functionalized graphene and insulated blocking layer

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Journal of Magnesium and Alloys 2024年第1期12卷 332-344页

作者： Z.Y.Xue X.J.Li J.h.Chu M.M.Li D.n.Zou L.B.Tong School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China State Key Laboratory of Advanced Design and Manufacturing for vehicle Body Hunan UniversityChangsha 410082China

the poor corrosion and wear resistances of Mg alloys seriously limit their potential applications in various *** conventional epoxy coating easily forms many intrinsic defects during the solidification process,which cannot provide sufficient *** the current study,we design a double-layer epoxy composite coating on Mg alloy with enhanced anti-corrosion/wear properties,via the spin-assisted assembly *** outer layer is functionalized graphene(FG)in waterborne epoxy resin(WEP)and the inner layer is Ce-based conversion(Ce)*** FG sheets can be homogeneously dispersed within the epoxy matrix to fill the intrinsic defects and improve the barrier *** Ce film connects the outer layer with the substrate,showing the transition *** corrosion rate of Ce/WEP/FG composite coating is 2131 times lower than that of bare Mg alloy,and the wear rate is decreased by~90%.the improved corrosion resistance is attributed to the labyrinth effect(hindering the penetration of corrosive medium)and the obstruction of galvanic coupling *** synergistic effect derived from the FG sheet and blocking layer exhibits great potential in realizing the improvement of multi-functional integration,which will open up a new avenue for the development of novel composite protection coatings of Mg alloys.

关键词： Mg alloy Functionalized graphene Epoxy coating Corrosion/wear resistance Blocking layer

hard life for sons in the nest?Sex-dependent offspring mortality in Great Tits in urban and forest areas

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Avian Research 2024年第1期15卷 91-97页

作者： nora Agh henriett Anna Dalvári Krisztián Szabó ivett Pipoly András Liker hUn-REn-PE Evolutionary Ecology Research Group University of PannoniaH-8200VeszpremPf.1158.Hungary Behavioral Ecology Research Group Center for Natural SciencesUniversity of PannoniaH-8200Pf.1158.VeszpremHungary Molecular Ecology Research Group Department of EcologyUniversity of Veterinary Medicine BudapestH-1400Pf.2.BudapestHungary Synlab hungary Ltd. H-1211Weiss Manfr´ed Str.5-7BudapestHungary

Sex-biased mortality can occur in birds during development,for example due to sexual differences in energy requirement and/or environmental sensitivity,or the effects of sex hormones or sex differences in the expression of mutations linked to sex *** extent of sex-bias in mortality may also be related to environmental conditions that influence offspring development and *** areas often provide poorer conditions for nestling development resulting in higher offspring mortality compared to natural areas,which may accelerate sex differences in offspring mortality in *** test this hypothesis,we examined the sex ratio of dead offspring in Great Tits(Parus major),using 427 samples of unhatched eggs and dead nestlings collected in two urban and two forest sites between 2013 and *** ratio of males in the whole sample of dead offspring(56.9%)was significantly higher than expected by an 1:1 ratio,and the strongest sex biases were detected in urban areas(57.6%males)and in young nestlings(however,the sex ratios of dead offspring did not differ significantly among study sites and between offspring developmental stages.29.3%of unhatched eggs contained a visible embryo,and the proportion of embryo-containing unhatched eggs did not differ significantly between urban and forest study *** results suggest male-biased offspring mortality in Great Tits,and highlight the need of large datasets to detect subtle differences between habitats and developmental stages.

关键词： Great Tit Urbanization nestling mortality Sex related differences

in-situ study of the microstructure evolution during tension of a Mg-Y-Zn-Al alloy processed by rapidly solidified ribbon consolidation technique

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Journal of Magnesium and Alloys 2024年第5期12卷 2024-2040页

作者： Jeno Gubicza Kristián Máthis Péter nagy Péter Jenei Zoltán hegedus Andrea Farkas Jozef vesely Shin-ichi inoue Daria Drozdenko Yoshihito Kawamura Department of Materials Physics Faculty of ScienceEotvos Loránd UniversityPázmány P.sétány 1/ABudapest H-1117Hungary Department of Physics of Materials Faculty of Mathematics and PhysicsCharles UniversityKe Karlovu 512116 Praha 2Czech Republic Deutsches Elektronen-Synchrotron DESY Notkestr.85Hamburg 22603Germany Magnesium Research Center Kumamoto University2-39-1 KurokamiChuo-kuKumamoto 860-8555Japan

Mg-Y-Zn-Al alloys processed by rapidly solidified ribbon consolidation(RSRC)technique exhibit an exceptional mechanical performance indicating promising application *** material has a bimodal microstructure consisting of fine recrystallized and coarse non-recrystallized grains with solute-rich stacking faults forming cluster arranged layers(CALs)and nanoplates(CAnaPs),or complete long period stacking ordered(LPSO)*** order to reveal the deformation mechanisms,in-situ synchrotron X-ray diffraction line profile analysis was employed for a detailed study of the dislocation arrangement created during tension in Mg-0.9%Zn-2.05%Y-0.15%Al(at%)*** uncovering the effect of the initial microstructure on the mechanical performance,additional samples were obtained by annealing of the as-consolidated specimen at 300 and 400℃ for 2 *** heat treatment at 300℃ had no significant effect on the initial microstructure,its evolution during tension and,thus,the overall deformation behavior under tensile *** the other hand,annealing at 400℃ resulted in a significant increase of the recrystallized grains fraction and a decrease of the dislocation density,leading to only minor degradation of the mechanical *** maximum dislocation density at the failure of the samples corresponding to the plastic strain of 10-25% was estimated to be about 16-20×10^(14)m^(-2).the diffraction profile analysis indicated that most dislocations formed during tension were of non-basal and pyramidal types,what was also in agreement with the Schmid factor values revealed independently from orientation *** was also shown that the dislocation-induced Taylor hardening was much lower below the plastic strain of 3% than above this value,which was explained by a model of the interaction between prismatic dislocations and CAnaPs/LPSO plates.

关键词： Mg-Zn-Y-Al alloy Long period stacking ordered(LPSO)phase Cluster arranged nanoplates(CAnaPs) Annealing Tension Dislocation density hardening

Brain Tumor Retrieval in MRi images with integration of Optimal Features

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Journal of harbin institute of Technology(new series) 2024年

作者： n v Shamna B Aziz Musthafa Department of Computer Science and Engineering， P A College of Engineering Department of Computer Science and Engineering， Bearys institute of Technology

this paper presents an approach to improve medical image retrieval， particularly for brain tumors， by addressing the gap between low-level visual and high-level perceived contents in MRi， X-ray， and CT scans. traditional methods based on color， shape， or texture are less effective. the proposed solution uses machine learning to handle high-dimensional image features， reducing computational complexity and mitigating issues caused by artifacts or noise. it employs a genetic algorithm for feature reduction and a hybrid residual Unet (hResUnet) model for region-of-interest (ROi) segmentation and classification， with enhanced image preprocessing. the study examines various loss functions， finding that a hybrid loss function yields superior results， and the GA-hResUnet model outperforms the hResUnet. Comparative analysis with state-of-the-art models shows a 4% improvement in retrieval accuracy.

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Photonuclear reactions on stable isotopes of selenium at bremsstrahlung end-point energies of 10-23 Mev

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Chinese Physics C 2024年第2期48卷 91-103页

作者： F.A.Rasulova n.v.Aksenov S.i.Alekseev R.A.Aliev S.S.Belyshev i.Chuprakov n.Yu.Fursova A.S.Madumarov J.h.Khushvaktov A.A.Kuznetsov B.S.Yuldashev Joint institute for nuclear Research DubnaRussia institute of nuclear Physics of the Academy of Sciences of the Republic of Uzbekistan TashkentUzbekistan Faculty of Chemistry of Lomonosov Moscow State University MoscowRussia national Research Center"Kurchatov institute" MoscowRussia Skobeltsyn institute of nuclear Physics of Lomonosov Moscow State University MoscowRussia Faculty of Physics of Lomonosov Moscow State University MoscowRussia institute of nuclear Physics AlmatyRepublic of Kazakhstan

in this study,experiments were performed at bremsstrahlung end-point energies of 10-23 Mev with the beam from the MT-25 microtron using theγ-activation *** experimental values of relative yields were compared with theoretical results obtained on the basis of TALYS with the standard parameters and the combined model of photonucleon *** isospin splitting in the combined model of photonucleon reactions allows describing experimental data on reactions with proton escape in the energy range from 10 to 23 ***,taking into account isospin splitting is necessary for a correct description of the decay of the giant dipole resonance.

关键词： bremsstrahlung photon cross section isospin splitting giant dipole resonance

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Current Zoology 2024年第1期70卷 1-12页

作者： Lucia v.Sommaro Juan J.Martinez Marina B.Chiappero Andrea R.Steinmann Cristina n.Gardenal JoséW.Priotto Laboratorio de Ecologia Evolutiva y Biogeografia Instituto de Ecorregiones Andinas(INECoA)Universidad Nacional de Jujuy-Consejo Nacional de Investigaciones Cientificas y Tecnicas(CONICET)San Salvador de JujuyJujuyArgentina instituto de Diversidad y Ecologia Animal(iDEA) Consejo Nacional de Investigaciones Cientificas y Técnicas(CONICET)and Universidad Nacionalde CordobaCordobaArgentina Catedra de Genética de Poblaciones y Evolucion Facultad de Ciencias ExactasFisicas y NaturalesUniversidad Nacional de CordobaCordobaArgentina Grupo de investigaciones en Ecologia Poblacional y Comportamental(GiEPCO) Instituto de Ciencias de la TierraBiodiversidad y Ambiente(ICBiA)Universidad Nacional de Rio Cuarto-Consejo Nacional de Investigaciones Cientificas y Técnicas(CONICET)Rio CuartoCordobaArgentina

the sex-biased dispersal and kinship dynamics are important factors shaping the spatial distribution of individuals and are key parameters affecting a variety of ecological and evolutionary ***,we studied the spatial distribution of related individuals within a population of corn mice Calomys musculinus in a seasonal cycle to infer dispersal *** sampling was carried out from spring 2005 to winter 2006 in field borders of intensively managed *** data from 346 individuals with 9 microsatellites showed spatial genetic structure was weak for males,but not for *** results indicate a complex spatial kinship dynamic of related females across all ***,contrary to our expectations,dispersal distances decrease with the increase of the population ***,male dispersal distances were greater when population abundance increased and thus the availability of active *** disperse greater distances to mate and sire offspring with distant females as a possible inbreeding avoidance *** study shows that *** is capable of much greater scattering distances than previously reported and that dispersal occurs fluidly and without barriers across the *** indirect benefit of dispersal on individual fitness could be related to relaxing the competition in the natal area and increasing the mating *** study highlights the value of combining genetic relatedness,fieldwork observations,and behavioral data to estimate dispersal at a fine geographical scale.

关键词： dispersal distances kinship dynamics microsatellite small mammals spatial autocorrelation