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Tree growth is more limited by drought in rear-edge f.rests most of.the times

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f.rest Ecosystems 2021年第2期8卷 330-344页

作者： J.Julio Camarero Antonio Gazol gabriel Sangüesa-Barreda Marta Vergarechea Raquel Alf.ro-Sánchez Nicolás Cattaneo Sergio M.Vicente-Serrano Instituto Pirenaico de Ecología(IPE-CSIC) Avda.Montañana 1005E-50192 ZaragozaSpain Ei f.B-iu f.R University of ValladolidCampus Duques de SoriaE-42004 SoriaSpain NIBIO Norwegian Institute of Bioeconomy ResearchPostboks 155NO-1431ÅsNorway Department of.Biology Wilfrid Laurier UniversityN2L 3C575 Univ.Avenue WWaterlooOntarioCanada

Background:Equatorward,rear-edge tree populations are natural monitors to estimate species vulnerability to climate *** to biogeographical theory,exposition to drought events increases with increasing aridity towards the equator and the growth of.southern tree populations will be more vulnerable to drought than in central ***,the ecological and biogeographical margins can mismatch due to the impact of.ecological f.ctors(topography,soils)or tree-species acclimation that can blur large-scale geographical imprints in trees responses to drought making northern populations more drought ***:We tested these ideas in six tree species,three angiosperms(f.gus sylvatica,Quercus robur,Quercus petraea)and three gymnosperms(Abies alba,Pinus sylvestris and Pinus uncinata)by comparing rear-edge tree populations subjected to dif.erent degrees of.*** used dendrochronology to compare the radial-growth patterns of.these species in northern,intermediate,and southern tree populations at the continental rear *** and conclusions:We f.und marked variations in growth variability between species with coherent patterns of.stronger drought signals in the tree-ring series of.the southern populations of.***,***,and *** was also observed in species f.om cool-wet sites(*** and ***),despite their limited responsiveness to ***,in the case of.*** the intermediate population showed the strongest relationship to *** drought-sensitive species as *** and ***,southern populations presented more variable growth which was enhanced by cool-wet conditions f.om late spring to *** f.und a trend of.enhanced vulnerability to drought in these two *** response of.tree growth to drought has a marked biogeographical component characterized by increased drought sensitivity in southern populations even within the species distribution rear ***,the relationship

关键词： Climate change Dendroecology Latitudinal gradient Mediterranean f.rests Standardized evapotranspiration precipitation index(SPEI)

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Targets with cone-shaped microstructures f.om various materials f.r enhanced high-intensity laser-matter interaction

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High Power Laser Science and Engineering 2021年第2期9卷 168-173页

作者： Tina Ebert RenéHeber Torsten Abel Johannes Bieker gabriel Schaumann and Markus Roth Institut f.r Kernphysik Department of PhysicsTechnische Universität Darmstadt64289 DarmstadtGermany Integrierte Mikro-Nano-Systeme Department of Electrical Engineering and Information TechnologyTechnische Universität Darmstadt64283 DarmstadtGermany

Targets with microstructured f.ont surf.ces have shown great potential in improving high-intensity laser–matter *** present cone-shaped microstructures made out of.silicon and titanium created by ultrashort laser pulse processing with dif.erent *** addition,we illustrate a process chain based on moulding to recreate the laser-processed samples out of.polydimethylsiloxane,polystyrol and *** all described methods,samples of.large sizes can be manuf.ctured,theref.re allowing time-ef.icient,cost-reduced and reliable ways to f.bricate large quantities of.identical targets.

关键词： microstructured targets moulding particle acceleration ultrashort laser pulse processing X-ray generation

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Relationship between methylation and colonic inf.ammation in inf.ammatory bowel disease

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World Journal of.Gastroenterology 2014年第30期20卷 10591-10598页

作者： Triana Lobaton Daniel Azuara f.ancisco Rodriguez-Moranta Carolina Loayza Xavier Sanjuan Javier de Oca Ana f.rnandez-Robles Jordi Guardiola gabriel Capella Department of.Gastroenterology University Hospital of BellvitgeIDIBELLHospitalet de Llobregat08907 BarcelonaSpain Translational Research Laboratory Catalan Institute of OncologyIDIBELLHospitalet de Llobregat08907 BarcelonaSpain Department of.Pathology University Hospital of BellvitgeIDIBELLHospitalet de Llobregat08907 BarcelonaSpain Department of.Surgery Colorectal UnitUniversity Hospital of BellvitgeIDIBELLHospitalet de Llobregat08907 BarcelonaSpain

AIM:To investigate the relationship between the methylation status in the SLIT2 and TGf.2 promoters and colonic inf.ammation in inf.ammatory bowel disease ***:We evaluated the methylation status of.2genes(SLIT2 and TGf.2)in 226 biopsies taken f.om62 colonoscopies of.38 patients(29 ulcerative colitis and 9 Crohn’s colitis)using methylation-specif.c melting curve *** relationships between methylation status and clinical,biological,endoscopic and histological activities were ***-three of.the 38patients had a second colonoscopy and were included in a longitudinal *** results were given as the means±SD of.the sample and range,except when *** t analysis,U Mann Whitney and ANOVA f.ctor were used to compare the *** results were based on theχ2 ***:SLIT2 methylation was more f.equent in samples with endoscopic activity than with endoscopic remission(55%vs 18%,Pf.ammation(56.5%)than in samples with chronic(24%)or absent inf.ammation(15%)(Pf.r TGf.2methylation,the correlation was only signif.cant with endoscopic *** was higher in the distal colon f.r both genes(Pf.r SLIT2 and P=0.022f.r TGf.2).In the multivariate analysis,only inf.ammation status(and not disease duration or extension)was independently associated with SLIT2 methylation[OR=6.6(95%CI:1.65-27.36),P=0.009].In the longitudinal analysis,the maintenance of.endoscopic remission was protective f.r ***:Endoscopic and histological inf.ammation are predictive f.r SLIT2 methylation.

关键词： Colonic inf.ammation Inf.ammatory bowel disease Aberrant methylation Dysplasia Colitis associated colorectal cancer

Anomalous transport of.light at the phase transition to localization:strong dependence with incident angle

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Photonics Research 2018年第10期 55-68页

作者： IPEN M.C.S.XAVIER IPEN VALDECI MESTRE WELITON S.MARTINS gabriel f.BASSO V.A.ERMAKOV f.C.MARQUES GILBERTO f.DE S Instituto de Pesquisas Energéticas e Nucleares CNEN Departamento de f.′sica Universidade Federal da Para?′ba Departamento de f.′sica Universidade Estadual da Para?′ba 4. Instituto de Pesquisas Energéticas e Nucleares CNEN 5. CCEA Universidade Estadual da Para?′ba 6. Departamento de F?′sica Universidade Federal Rural de Pernambuco 7. Departamento de Informática Universidade Federal da Para?′ba 8. Departamento de F?′sica Aplicada Universidade Estadual de Campinas 9. Qu?′mica Fundamental Universidade Federal de Pernambuco

There has been a growing interest in disordered optical media in recent years due to their potential applications in solar collectors, random lasers, light conf.nement, and other advanced photonic f.nctions. This paper studies the transport of.light f.r dif.erent incidence angles in a strongly disordered optical medium composed of.core-shell TiO@Silica nanoparticles suspended in an ethanol solution. A decrease of.optical conductance and an increase of.absorption near the input border are reported when the incidence angle increases. The specular ref.ection, measured f.r the photons that enter the sample, is lower than the ef.ective internal ref.ection undergone by the coherently backscattered photons in the exact opposite direction, indicating a nonreciprocal propagation of.*** study represents a novel approach in order to understand the complex physics involved at the phase transition to localization.

关键词： der exp Anomalous transport of.light at the phase transition to localization:strong dependence with incident angle

Predominance of.non-adiabatic ef.ects in zero-point renormalization of.the electronic band gap

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npj Computational Materials 2020年第1期6卷 297-304页

作者： Anna Miglio Véronique Brousseau-Couture Emile Godbout gabriel Antonius Yang-Hao Chan Steven G.Louie Michel Côté Matteo Giantomassi Xavier Gonze Institute of.Condensed Matter and Nanosciences UCLouvainB-1348 Louvain-la-NeuveBelgium Département de Physique et Regroupement Québécois sur les Matériaux de Pointe Universitéde MontrealC.P.6128Succursale Centre-VilleMontréal H3C 3J7Canada Department of.Physics University of California at BerkeleyBerkeleyCA 94720USA Materials Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA Département de Chimie Biochimie et PhysiqueInstitut de recherche sur l’hydrogèneUniversitédu QuébecàTrois-RivièresTrois-Rivières G8Z 4M3Canada Skolkovo Institute of.Science and Technology Skolkovo Innovation CenterNobel St.3Moscow 143026Russia

Electronic and optical properties of.materials are af.ected by atomic motion through the electron–phonon interaction:not only band gaps change with temperature,but even at absolute zero temperature,zero-point motion causes band-gap *** present a large-scale f.rst-principles evaluation of.the zero-point renormalization of.band edges beyond the adiabatic *** materials with light elements,the band gap renormalization is of.en larger than 0.3 eV,and up to 0.7 *** ef.ect cannot be ignored if.accurate band gaps are *** inf.ared-active materials,global agreement with available experimental data is obtained only when non-adiabatic ef.ects are taken into *** even dominate zero-point renormalization f.r many materials,as shown by a generalized f.öhlich model that includes multiple phonon branches,anisotropic and degenerate electronic extrema,whose range of.validity is established by comparison with f.rst-principles results.

关键词： adiabatic renormalization phonon

Histogram Matched Chest X-Rays Based Tuberculosis Detection Using CNN

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Computer Systems Science & Engineering 2023年第1期44卷 81-97页

作者： Joe Louis Paul Ignatius Sasirekha Selvakumar Kavin gabriel Joe Louis Paul Aadhithya B.Kailash S.Keertivaas S.A.J.Akarvin Raja Prajan Department of.Inf.rmation Technology Sri Sivasubramaniya Nadar College of EngineeringRajiv Gandhi Salai(OMR)KalavakkamChennai603110Tamil NaduIndia Gullas College of.Medicine-University of.Visayas BaniladMandaue City6014CebuPhilippines

Tuberculosis(TB)is a severe inf.ction that mostly af.ects the lungs and kills millions of.people’s lives every *** can be diagnosed using chest X-rays(CXR)and data-driven deep learning(DL)*** of.its better automated f.ature extraction capability,convolutional neural net-works(CNNs)trained on natural images are particularly ef.ective in image cate-gorization.A combination of.3001 normal and 3001 TB CXR images was gathered f.r this study f.om dif.erent accessible public *** dif.erent deep CNNs(Resnet50,Resnet101,Resnet152,InceptionV3,VGG16,VGG19,DenseNet121,DenseNet169,DenseNet201,MobileNet)are trained and tested f.r identif.ing TB and normal *** study presents a deep CNN approach based on histogram matched CXR images that does not require object segmenta-tion of.interest,and this coupled methodology of.histogram matching with the CXRs improves the accuracy and detection perf.rmance of.CNN models f.r TB ***,this research contains two separate experiments that used CXR images with and without histogram matching to classif. TB and non-TB CXRs using deep *** was able to accurately detect TB f.om CXR images using pre-processing,data augmentation,and deep CNN *** histogram matching the best accuracy,sensitivity,specif.city,precision and f.-score in the detection of.TB using CXR images among ten models are 99.25%,99.48%,99.52%,99.48%and 99.22%*** histogram matching the best accuracy,sensitivity,specif.city,precision and f.-score are 99.58%,99.82%,99.67%,99.65%and 99.56%*** proposed meth-odology,which has cutting-edge perf.rmance,will be usef.l in computer-assisted TB diagnosis and aids in minimizing irregularities in TB detection in developing countries.

关键词： Tuberculosis detection chest x-ray(CXR) convolutional neural networks(CNNs) transf.r learning histogram matching

Automatic Detection of.COVID-19 Inf.ction Using Chest X-Ray Images Through Transf.r Learning

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IEEE/CAA Journal of.Automatica Sinica 2021年第1期8卷 239-248页

作者： Elene f.rmeza Ohata gabriel Maia Bezerra João Victor Souza das Chagas Aloísio Vieira Lira Neto Adriano Bessa Albuquerque Victor Hugo Cde Albuquerque Pedro Pedrosa Rebouças f.lho the Universidade f.deral do Ceará FortalezaCE 60455-970and also with the Instituto Federal do CearáFortalezaCE 60040-215Brazil the Instituto f.deral do Ceará FortalezaCE 60040-215Brazil the Universidade de f.rtaleza FortalezaCE 60811-905Brazil

The new coronavirus(COVID-19),declared by the World Health Organization as a pandemic,has inf.cted more than 1 million people and killed more than 50 *** inf.ction caused by COVID-19 can develop into pneumonia,which can be detected by a chest X-ray exam and should be treated *** this work,we propose an automatic detection method f.r COVID-19 inf.ction based on chest X-ray *** datasets constructed f.r this study are composed of.94 X-ray images of.patients diagnosed with coronavirus and 194 X-ray images of.healthy *** f.w images of.patients with COVID-19 are publicly available,we apply the concept of.transf.r learning f.r this *** use dif.erent architectures of.convolutional neural networks(CNNs)trained on Image Net,and adapt them to behave as f.ature extractors f.r the X-ray ***,the CNNs are combined with consolidated machine learning methods,such as k-Nearest Neighbor,Bayes,Random f.rest,multilayer perceptron(MLP),and support vector machine(SVM).The results show that,f.r one of.the datasets,the extractor-classif.er pair with the best perf.rmance is the Mobile Net architecture with the SVM classif.er using a linear kernel,which achieves an accuracy and an f.-score of.98.5%.f.r the other dataset,the best pair is Dense Net201 with MLP,achieving an accuracy and an f.-score of.95.6%.Thus,the proposed approach demonstrates ef.iciency in detecting COVID-19 in X-ray images.

关键词： Convolutional neural networks(CNNs) COVID-19 transf.r learning X-ray

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让芯片内部一览无余

科技纵览 2022年第5期 36-41,3页

作者： Anthony f.J.Levi gabriel Aeppli 不详

烤蛋糕的时候,我们很难知道烤箱里何时才能达到我们想要的状态。对于微电子芯片来说亦如此,其中的风险甚至更高:工程师们如何确认芯片内部完全符合设计师的意图?半导体设计公司如何判断其知识产权是否被盗?更令人担忧的是,谁能确定其中... 详细信息

烤蛋糕的时候,我们很难知道烤箱里何时才能达到我们想要的状态。对于微电子芯片来说亦如此,其中的风险甚至更高:工程师们如何确认芯片内部完全符合设计师的意图?半导体设计公司如何判断其知识产权是否被盗?更令人担忧的是,谁能确定其中没有秘密嵌入自毁开关或其他硬件木马?

关键词：微电子芯片硬件木马知识产权工程师们半导体设计公司

Antibacterial Ef.ects of.Ethanolic Extract of.Zehneria scabra on Quails Artif.cially Inf.cted with Salmonella Enteritidis

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Journal of.Pharmacy and Pharmacology 2021年第11期9卷 387-396页

作者： Herman M.f.Biekop Marc K Kouam Vivian Yengeh gabriel T Kamsu Bridget Katte Alexis Teguia Biekop Herman Department of.Animal Science Faculty of Agronomy and Agricultural SciencesPO BOX 188DschangCameroon Center f.r Research on f.lariases and other Tropical Diseases(CRf.lMT) P.O.Box 5797YaoundéCameroon Microbiology and Antimicrobial Substances Research Unit Faculty of ScienceUniversity of DschangCameroon 不详

Antimicrobial use in livestock is f.ced with various challenges including emergence of.antimicrobial resistance and presence of.drug residues in meat products,hence the need f.r *** aim of.this work was to assess the ef.ect a plant(Zehneria scabra)extract on Salmonella inf.cted quails,as an alternative to antibiotic *** were randomly assigned into six groups each containing twelve *** neutral control(T0)group was not inf.cted and received tap water whereas other groups were *** negative control(T-)received tap *** positive control(T+)received a single dose of.oxytetracycline(20 mg/kg).T1,T2 andT3 orally received the plant extract at the f.llowing respective doses:9,18 and 37 mg/*** were inf.cted by oral administration of.a single dose of.Salmonella Enteritidis(10^(5)Cf.).Haematological and biochemical parameters were *** day 2 to day 9 to day 16,the bacterial load of.all treatment groups(T+,T1,T2,T3)*** inf.ction resulted in a signif.cant(pf.alanine aminotransf.rase,triglycerides,total cholesterol and white blood cells,and a signif.cant decrease in the liver and kidney protein *** treatment resulted in the correction of.the af.rementioned *** plant extract(18 mg/kg)is as ef.ective as oxytetracycline,and can be saf.ly used in phytomedicine f.r the treatment of.Salmonella Enteritidis inf.ction without kidney and liver damage.

关键词： Zehneria scabra Salmonella Enteritidis antisalmonellal activity quails