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A PREDICtOR MODIFICAtION tO tHE EBDF MEtHOD FOR StIFF SYStEMS

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Journal of Computational Mathematics 2011年第2期29卷 199-214页

作者： Elisabete alberdi Juan Jose Anza Lea Artibai Ikastetxea Xemein Avenue 19 48270 Markina-Xemein (Vizcaya) Spain Department of Applied Mathematics ETS de Ingenieria de Bilbao Universidad del Pais Vasco Alameda de Urquijo s/n 48013 Bilbao Spain

In this paper we modify the EBDF method using the NDFs as predictors instead of BDFs. this modification, that we call ENDF, implies the local truncation error being smaller than in the EBDF method without losing too much stability. We will also introduce two more changes, called ENBDF and EBNDF methods. In the first one, the NDF method is used as the first predictor and the BDF as the second predictor. In the EBNDF, the BDF is the first predictor and the NDF is the second one. In both modifications the local truncation error is smaller than in the EBDF. Moreover, the EBNDF method has a larger stability region than the EBDF.

关键词： Backward differentiation formula (BDF) EBDF Predictor Stability Stiff Systems.

tHE INtEGRAtION OF StIFF SYStEMS OF ODEs USING NDFs AND MEBDFs

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Journal of Computational Mathematics 2013年第2期31卷 175-189页

作者： Elisabete alberdi Celaya Juan Jose Anza Department of Applied Mathematics EUIT de Minas y Obras P(tblicas Universidad del Pals Vasco UPV/EHU Colina de Beurko s/n 48902 Barakaldo Spain Department of Applied Mathematics ETS de Ingenieria de Bilbao Universidad del Pals Vasco UPV/EHU Alameda de Urquijo s/n 48013 Bilbao Spain

In this paper we modify the MEBDF method using the NDFs as predictors instead of the BDFs. We have done it in three different ways： changing both predictors of the MEBDF, changing only the first predictor and changing only the second one. We have called the new methods MENDF, MENBDF and MEBNDF respectively. the new methods are A-stable up to order 4 and the stability properties of the new methods are better than the MEBDF method.

关键词： BDF NDF MEBDF Stiff ODEs Stability.

Forest Biodiversity Assessment in Peruvian Andean Montane Cloud Forest

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Journal of Mountain Science 2012年第3期9卷 372-384页

作者： Alicia Ledo Sonia Condés Iciar alberdi Universidad Politécnica de Madrid.Escuela técnica Superior de Ingenieros de Montes.Ciudad Universitaria sn.28040MadridSpain CIFOR-INIA Ctra.de La Corua Km 7.5 28040MadridSpain

Cloud forests are unusual and fragile habitats, being one of the least studied and least understood ecosystems. the tropical Andean dominion is considered one of the most significant places in the world as regards biological diversity, with a very high level of endemism. the biodiversity was analysed in an isolated remnant area of a tropical montane cloud forest known as the "Bosque de Neblina de Cuyas", in the North of the Peruvian Andean range. Composition, structure and dead wood were measured or estimated. the values obtained were compared with other cloud forests. the study revealed a high level of forest biodiversity, although the level of biodiversity differs from one area to another: in the inner areas, where human pressure is almost inexistent, the biodiversity values increase. the high species richness and the low dominance among species bear testimony to this montane cloud forest as a real enclave of biodiversity.

关键词： Andean Range Biodiversity Dead wood Montane forest Species composition Stand structure tropical forest

Deep material network via a quilting strategy: visualization for explainability and recursive training for improved accuracy

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npj Computational Materials 2023年第1期9卷 1023-1038页

作者： Dongil Shin Ryan alberdi Ricardo A.Lebensohn Rémi Dingreville Center for Integrated Nanotechnologies Sandia National LaboratoriesAlbuquerqueNM 87185USA Simulation Modeling Sciences Sandia National LaboratoriesAlbuquerqueNM 87185USA theoretical Division Los Alamos National LaboratoryLos AlamosNM 87845USA

Recent developments integrating micromechanics and neural networks offer promising paths for rapid predictions of the response of heterogeneous materials with similar accuracy as direct numerical *** deep material network is one such approaches,featuring a multi-layer network and micromechanics building blocks trained on anisotropic linear elastic *** trained,the network acts as a reduced-order model,which can extrapolate the material’s behavior to more general constitutive laws,including nonlinear behaviors,without the need to be ***,current training methods initialize network parameters randomly,incurring inevitable training and calibration ***,we introduce a way to visualize the network parameters as an analogous unit cell and use this visualization to“quilt”patches of shallower networks to initialize deeper networks for a recursive training *** result is an improvement in the accuracy and calibration performance of the network and an intuitive visual representation of the network for better explainability.

关键词： networks Deep network

twenty years of population dynamics in European beech-oak forest at their rear range margin anticipate changes in its structure and composition

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Forest Ecosystems 2024年第3期11卷 358-370页

作者： álvaro Rubio-Cuadrado Iciar alberdi Isabel Canellas Fernando Montes Jesús Rodríguez-Calcerrada Rosana López Guillermo G.Gordaliza maría Valbuena-Carabana Nikos Nanos Ramón Perea Luis Gil Departamento de dinamica y gestion forestal Instituto de Ciencias Forestales(ICIFOR-INIA)CSICCtra.La Coruna km 7.528040MadridSpain Departamento de Sistemas y Recursos Naturales Escuela Tecnica Superior de Ingeniería de MontesForestal y del Medio NaturalUniversidad Politecnica de Madrid.Ciudad Universitaria s/n28040MadridSpain School of Forestry and Natural Environment Aristotle University of ThessalonikiUniversity Campus54124ThessalonikiGreece

there is an increasing interest in restoring degraded forests,which occupy half of the forest *** the forms of restoration,passive restoration,which involves the elimination of degrading factors and the free evolution of natural dynamics by applying minimal or no management,is gaining *** dynamics is difficult to predict due to the influence of multiple interacting factors such as climatic and edaphic conditions,composition and abundance of species,and the successional character of these ***,we study the natural dynamics of a mixed forest located in central Spain,which maintained an open forest structure,due to intensive use,until grazing and cutting were banned in the *** most frequent woody species in this forest are Fagus sylvatica,Quercus petraea,Quercus pyrenaica,Ilex aquifolium,Sorbus aucuparia,Sorbus aria and Prunus avium,with contrasting shade and drought *** species are common in temperate European deciduous forest and are found here near their southern distribution limit,except for *** order to analyze forest dynamics and composition,three inventories were carried out in 1994,2005 and *** results show that,despite the Mediterranean influence,the natural dynamics of this forest has been mainly determined by different levels of shade *** the abandonment of grazing and cutting,*** expanded rapidly due to its lower shade tolerance,whereas after canopy closure and forest densification,shade-tolerant species gained ground,particularly ***,despite its lower drought and late-frost *** the current dynamics continue,*** will overtake the rest of the species,which will be relegated to sites with shallow soils and steep ***,all the multi-centennial beech trees,which are undergoing a rapid mortality and decline process,will disappear.

关键词： Forest succession Secondary forest Woodland Mixed forest Competition Recruitment

Contemporary climate infuence on variability patterns of Anadenanthera colubrina ***,a key species in seasonally dry tropical forests

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Journal of Forestry Research 2022年第1期33卷 89-101页

作者： maría Victoria García maría Eugenia Barrandeguy Kathleen Prinz Genética de Poblaciones y Cuantitativa-Departamento de Genética-Facultad de Ciencias Exactas Químicas y Naturales-Universidad Nacional deMisionesInstituto de Biología Subtropical(UNaM-CONICET)Nodo PosadasFélix de Azara 15523300 PosadasArgentina Consejo Nacional de Investigaciones Científicas Y técnicas(CONICEt) PosadasMisionesArgentina Institute of Systematic Botany With Herbarium Haussknecht and Botanical Gardens Friedrich-Schiller-University Jena07743 JenaGermany

the distribution of many plant species has been shaped by climate changes,and their current phenotypic and genetic variability refect microclimatically suitable *** study relates contemporary climate to variability patterns of phenotypic traits and molecular markers in the Argentinean distribution of Anadenanthera colubrina ***,as well as to identify the most relevant phenotypic trait or molecular marker associated with those *** from four populations in both biogeographic provinces,Paranaense and Yungas,were *** analyses and multiple linear regressions were carried out to determine relationships among phenotypic traits and nuclear microsatellites,respectively,to climatic variables,and to identify the phenotypic traits as well as nuclear microsatellite loci most sensitive to *** and three clusters of individuals were detected based on genetic and phenotypic data,*** clusters based on genetic data refected the biogeographic origin of *** traits were the most relevant indicators of climatic *** microsatellite locus Ac41.1 appeared to be non-neutral presenting a strong correlation with climate variable temperature *** findings show complex patterns of genetic and phenotypic variability in the Argentinean distribution of *** *** related to the present or contemporary climate,and provides an example for an integrative approach to better understand climate impact on contemporary genetic and phenotypic variability in light of global climate change.

关键词： Contemporary climate Curupay Genetic variability Phenotypic variability Seasonally dry tropical forests

Anterior and posterior capsule densitometry levels after femtosecond laser-assisted cataract surgery

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International Journal of Ophthalmology(English edition) 2018年第4期11卷 623-628页

作者： txomin alberdi Javier Mendicute Lucia Bascaran Olatz Barandika Javier Ruiz-Ederra Department of Ophthalmology Donostla University HospitalDonostia-San Sebastian 20014Spain Biodonostia Health Research Institute Donostia-San Sebastian 20014Spain

AIM： to analyze and compare five different variables over one year follow-up（1 wk, 1, 3, 6 and 12 mo）： anterior capsule（AC）, and posterior capsule（PC） area densitometry values, AC and PC linear densitometry values, and AC opening area reduction ratio after femtosecond laserassisted cataract surgery. MEtHODS： this was a prospective comparative study. Seventy-one patients underwent femtosecond laser-assisted cataract surgery on single eye between June 2014 and December 2015. A 5.0 mm diameter laser assisted anterior capsulotomy was performed on all eyes. In every postsurgery evaluation, AC opacificaction（ACO） and PC opacification（PCO） density levels were provided by Oculus Pentacam·HR using area and linear densitometry methods. Digital images were captured with a slit-lamp topcon photographic camera and IMAGEnet· 5 software. the AC opening area on the digital images was measured using the Sketchandcalc area calculator and converted to reduction ratio ***： Using Pearson correlation coefficient（PCC）, we found no correlation（r=-0.091, P=0.46） in the twelfth month assessment between the evolution of ACO area densitometry values and PCO area densitometry values considered as independent variables. We found no correlation, using PCC（r=-0.096, P=0.43） between the evolution of ACO linear densitometry values and PCO linear densitometry values, in the twelfth month visit, working both as independent variables. AC linear densitometry levels and AC area densitometry levels continued to grow strongly from sixth to twelfth months. Analysis of the values of AC opening area reduction ratio（1 wk, 1, 3, 6, 12 mo） revealed statistically significant differences between the values of successive examinations but the magnitude of the change decreased. In the final period of monitoring between six and twelve months the magnitude of change was ***： Our results show strong increases of Scheimpflug ACO densitometry values from the sixth to the twelfth month while capsulorh

关键词： anterior capsule opacification area densitometry femtosecond laser-assisted cataract surgery linear densitometry Pentacam?HR Scheimpflug posterior capsule pacification

Late traumatic flap dislocation seven years after femtosecond laser-assisted in situ keratomileusis

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International Journal of Ophthalmology(English edition) 2019年第5期12卷 862-865页

作者： maría t.Alvarez Andrea Montesel Laurent Bataille Cataract and Refractive Surgery Department VISSUM Research and Development Department VISSUM

Dear Editor,I would like to report a case of late traumatic flap dislocation seven years after uncomplicated femtosecond laser-assisted laser in situ keratomileusis(Femto-LASIK).Postoperative laser-assisted laser in situ keratomileusis(LASIK)flap dislocation occurs in approximately 1%-2%of patients,and the greatest risk of non-traumatic flap shift occurs within the first post-operative day after the surgery,presumably as a result of a mechanical trauma[1-3].

关键词： LASIK Figure Femto

Angina bullosa hemorrhagica an enigmatic oral disease

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World Journal of Stomatology 2015年第1期4卷 1-7页

作者： Javier alberdi-Navarro maría Luisa Gainza-Cirauqui maría Prieto-Elías José Manuel Aguirre-Urizar Oral Medicine and Oral and Maxillofacial Pathology Units Dental Clinic Service Master in Oral Pathology Department of Stomatology II UFI 11/25 University of the Basque Country/EHU48950 Leioa Spain Department of Dental Surgery Faculty of Dental Surgery University of Malta 2080 Msida Malta

Angina bullosa hemorrhagica(ABH) is an enigmatic oral disorder described for the first time by Badham in 1967 to define blisters with a hematic content in the oralcavity and oropharynx unrelated to any hematological, dermatological or systemic disease. the ABH is an uncommon disease of the oral cavity distinctively affecting adults, with the highest incidence over the 5th decade of life. this process is considered nowadays to have a multifactorial etiopathogenesis, where mild oral traumatisms can trigger the blisters in susceptible individuals. Certain association on the onset of the lesion with the chronic use of inhaled steroids and, more controversially, with triggering systemic disorders, such as, diabetes or hypertension has been described. Characteristically, the ABH blisters are acute and are located on the lining mucosa, more frequently on the soft palate. Usually, the lesions are solitary and rupture easily, resulting in a superficial ulceration that heals quickly without scarring. the histopathological analysis shows a subepithelial blister containing blood and direct immunofluorescence on the epithelium is negative. the differential diagnosis should consider all oral vesiculobullous disorders with hematic content, including mucocutaneos, hematological or cystic pathology. the diagnosis of ABH is clearly clinical, although the biopsy might be helpful on atypical or abnormally recurrent cases. the general prognosis of ABH is good and the treatment is symptomatic.

关键词： Angina Bullosa Hemorrhagica traumatic Blister