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冠状动脉CTA对于中低度冠心病风险男性和女性病人的准确性

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国际医学放射学杂志 2013年第1期 86-87页

作者： A.s.Dharampal s.l.papadopoulou A.Rossi A.C.Weustink N.R.A.Mollet W.Bob Meijboom 李琼 Department of Radiology Erasmus MCRoom Ca207a' s-Gravendijkwal 230P.O.Box 20403015 CERotterdamNetherlands

目的比较女性与男性低中度冠心病风险者中冠状动脉CT血管成像的诊断准确性。方法此回顾性研究包括有低中度冠心病风险的有症状病人,进行了介入冠状动脉造影和冠状动脉CTA检查。排除标准为既往曾行血管再通治疗或心肌梗死的病人。采用Duk... 详细信息

目的比较女性与男性低中度冠心病风险者中冠状动脉CT血管成像的诊断准确性。方法此回顾性研究包括有低中度冠心病风险的有症状病人,进行了介入冠状动脉造影和冠状动脉CTA检查。排除标准为既往曾行血管再通治疗或心肌梗死的病人。采用Duke风险评分初步评估冠心病的可能性。分别以小于30%和30%～90%为低度和中度风险。计算冠状动脉CTA在病人水平上显示阻塞性冠心病(管腔狭窄≥50%)的诊断准确性。以P<0.05有统计学意义。结果共有570例病人(46%为女性,262/570),分为低度(73%为女性,80/109)和中度(39%为女性,182/461)风险。无论男性和女性,低度和中度风险组,其间诊断的敏感度、特异度、阳性和阴性预测值的差异均没有统计学意义。在低风险组,对于女性和男性分别为97%和100%,79%和90%,80%和80%,97%和100%;而在中度风险组,对于女性和男性分别是99%和99%,72%和83%,88%和93%,98%和99%。结论冠状动脉CTA对于中低度冠心病风险的男性和女性有相似的诊断准确性。

关键词：冠状动脉女性冠心病冠状动脉病男性 CTA

Height-diameter models for King Boris fir(Abies borisii regis Mattf.) and scots pine(Pinus sylvestris l.) in Olympus and Pieria Mountains, Greece

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Journal of Mountain science 2024年第5期21卷 1475-1490页

作者： Dimitrios I.RAPTIs Dimitra papadopoulou Angeliki PsARRA Athanasios A.FAllIAs Aristides G.TsITsANIs Vassiliki KAZANA Renewable Natural Resource Management and Bioeconomy laboratory Department of Forest and Natural Environment SciencesInternational Hellenic University66100 DramaGreece

In forest science and practice, the total tree height is one of the basic morphometric attributes at the tree level and it has been closely linked with important stand attributes. In the current research, sixteen nonlinear functions for height prediction were tested in terms of their fitting ability against samples of Abies borisii regis and Pinus sylvestris trees from mountainous forests in central Greece. The fitting procedure was based on generalized nonlinear weighted regression. At the final stage, a five-quantile nonlinear height-diameter model was developed for both species through a quantile regression approach, to estimate the entire conditional distribution of tree height, enabling the evaluation of the diameter impact at various quantiles and providing a comprehensive understanding of the proposed relationship across the distribution. The results clearly showed that employing the diameter as the sole independent variable, the 3-parameter Hossfeld function and the 2-parameter N?slund function managed to explain approximately 84.0% and 81.7% of the total height variance in the case of King Boris fir and scots pine species, respectively. Furthermore, the models exhibited low levels of error in both cases(2.310m for the fir and 3.004m for the pine), yielding unbiased predictions for both fir(-0.002m) and pine(-0.004m). Notably, all the required assumptions for homogeneity and normality of the associated residuals were achieved through the weighting procedure, while the quantile regression approach provided additional insights into the height-diameter allometry of the specific species. The proposed models can turn into valuable tools for operational forest management planning, particularly for wood production and conservation of mountainous forest ecosystems.

关键词： Generalized nonlinear weighted regression Monte Carlo cross-validation Mountainous ecosystems Quantile regression Central Greece

Experimental implementation of phase triplicator gratings in a spatial light modulator

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Chinese Optics letters 2024年第2期22卷 64-69页

作者：高尚 María del Mar sánchez-lópez Ignacio Moreno Instituto de Bioingeniería Universidad Miguel HernándezElche 03202Spain Departamento de Física Aplicada Universidad Miguel HernándezElche 03202Spain Departamento de Ciencia de Materiales Óptica y Tec.Electr´onicaUniversidad Miguel HernándezElche 03202Spain

In this work,we compare different methods for implementing a triplicator,a phase grating that generates three equiintense diffraction *** design with optimal efficiency features a continuous phase profile,which cannot be easily reproduced,and is typically affected by *** compare its performance with binary and sinusoidal phase *** also analyze the effect of quantizing the phase ***,a random approach is adopted to eliminate the additional harmonic *** all cases,a liquid-crystal-on-silicon spatial light modulator is employed to experimentally verify and compare the different approaches.

关键词： diffraction gratings phase modulation triplicator spatial light modulators

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： C.Y.Morassuti A.P.l silva l.A.O.Nunes s.M.lima l.H.C.Andrade Optical and Photothermal spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of são Carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

Weighted Probability Density Estimator with Updated Bandwidths

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Journal of systems science & Complexity 2024年第2期37卷 886-906页

作者： WU Yi YU Wei WANG Xuejun PRAKAsA RAO B l s school of Big Data and Artificial Intelligence Chizhou UniversityChizhou 247000China school of Big Data and statistics Anhui UniversityHefei 230601China CR Rao Advanced Institute of Mathematics Statistics and Computer ScienceHyderabad 500046India

In this paper,the authors study a class of weighted version of probability density *** is shown that the weighted estimator contains some existing estimators of probability density,no matter they are recursive or *** statistical results including weak consistency,strong consistency,rate of strong consistency,and asymptotic normality are established under some mild ***,the random weighted estimator is also *** numerical simulations and a real data analysis are presented to study the numerical performances of the estimators.

关键词： Asymptotic normality consistency numerical simulation probability density real data analysis updated bandwidths weighted estimator

Model Change Active learning in Graph-Based semi-supervised learning

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1270-1298页

作者： Kevin s.Miller Andrea l.Bertozzi Department of Mathematics University of CaliforniaLos Angeles520 Portola PlazaLos AngelesCA 90095USA

Active learning in semi-supervised classification involves introducing additional labels for unlabelled data to improve the accuracy of the underlying classifier.A challenge is to identify which points to label to best improve performance while limiting the number of new labels."Model Change"active learning quantifies the resulting change incurred in the classifier by introducing the additional label(s).We pair this idea with graph-based semi-supervised learning(ssl)methods,that use the spectrum of the graph laplacian matrix,which can be truncated to avoid prohibitively large computational and storage *** consider a family of convex loss functions for which the acquisition function can be efficiently approximated using the laplace approximation of the posterior *** show a variety of multiclass examples that illustrate improved performance over prior state-of-art.

关键词： Active learning Graph-based methods semi-supervised learning(ssl) Graph laplacian

Resource management at the network edge for federated learning

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Digital Communications and Networks 2024年第3期10卷 765-782页

作者： silvana Trindade luiz F.Bittencourt Nelson l.s.da Fonseca Institute of Computing State University of CampinasCampinasBrazil

Federated learning has been explored as a promising solution for training machine learning models at the network edge,without sharing private user *** limited resources at the edge,new solutions must be developed to leverage the software and hardware resources as the existing solutions did not focus on resource management for network edge,specially for federated *** this paper,we describe the recent work on resource manage-ment at the edge and explore the challenges and future directions to allow the execution of federated learning at the *** such as the discovery of resources,deployment,load balancing,migration,and energy effi-ciency are discussed in the paper.

关键词： Resource management Edge computing Federated learning Machine learning

Four late-type Galaxies with Double Radio lobes and Properties of such Galaxies

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Research in Astronomy and Astrophysics 2024年第4期24卷 84-90页

作者： Z.s.Yuan X.Y.Gao Z.l.Wen J.l.Han National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAs Key laboratory of FAsT National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China school of Astronomy and space sciences University of Chinese Academy of SciencesBeijing 100049China

The triggering mechanism for radio lobes from late-type galaxies is not fully *** samples are desired for a thorough investigation and *** utilizing the optical data from the newly released Dark Energy spectroscopic Instrument imaging surveys and the radio sources from the NRAO VlA sky survey and the Faint Images of the Radio sky at Twenty-centimeter,we identify four late-type Galaxies with double Radio lobes(la GRls):J0217-3645,J0947+6220,J1412+3723 and J1736+*** previously known la GRls,we confirm the correlation between radio power P_(1.4GHz)and stellar mass M_(*)of host ***(25/35)la GRls belong to the blue cloud galaxies,while the newly identified cases in this work are located within the region of the red *** find a clear correlation between the differential radio power,i.e.,the offset from the P_(1.4GHz)-M_(*)relation,and the galaxy color,indicating that bluer galaxies at a fixed M_(*)tend to host more powerful radio ***,the majority(31/36)of la GRls are either located in a galaxy group or displaying a disturbed *** suggest that all of the galaxy mass,color and surrounding environment could play important roles in triggering radio lobes in late-type galaxies.

关键词： galaxies:active galaxies:jets galaxies:spiral radio continuum:galaxies

In search of a pan-coronavirus vaccine:next-generation vaccine design and immune mechanisms

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Cellular & Molecular Immunology 2024年第2期21卷 103-118页

作者： s.Cankat M.U.Demael l.swadling Division of Infection and Immunity Institute of Immunity and TransplantationUniversity College LondonPears BuildingLondon NW32PPUK

Members of the coronaviridae family are endemic to human populations and have caused several epidemics and pandemics in recent *** this review,we will discuss the feasibility of and progress toward the ultimate goal of creating a pan-coronavirus vaccine that can protect against infection and disease by all members of the coronavirus *** will detail the unmet clinical need associated with the continued transmission of sARs-CoV-2,MERs-CoV and the four seasonal coronaviruses(HCoV-OC43,Nl63,HKU1 and 229E)in humans and the potential for future zoonotic *** will highlight how first-generation sARs-CoV-2 vaccines and natural history studies have greatly increased our understanding of effective antiviral immunity to coronaviruses and have informed next-generation vaccine *** will then consider the ideal properties of a pan-coronavirus vaccine and propose a blueprint for the type of immunity that may offer ***,we will describe a subset of the diverse technologies and novel approaches being pursued with the goal of developing broadly or universally protective vaccines for coronaviruses.

关键词： Vaccine Coronavirus Cross-reactive immunity Cross-protection Universal