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Journal of Hydrodynamics 2012年第6期24卷 888-898页

作者： GU Ji-jun AN Chen LEVI Carlos SU Jian Ocean Engineering Program COPPEUniversidade Federal do Rio de Janeiro Nuclear Engineering Program COPPEUniversidade Federal do Rio de Janeiro

The Generalized Integral Transform Technique （GITT） was applied to predict dynamic response of Vortex-Induced Vibration （VIV） of a long flexible cylinder. A nonlinear wake oscillator model was used to represent the cross-flow force acting on the cylinder, leading to a coupled system of second-order Partial Differential Equations （PDEs） in temporal variable. The GITT approach was used to transform the system of PDEs to a system of Ordinary Differential Equations （ODEs）, which was numerically solved by using the Adams-Moulton and Gear method （DIVPAG） developed by the International Mathematics and Statistics Library （IMSL）. Numerical results were presented for comparison to those given by the finite difference method and experimental results, allowing a critical evaluation of the technique performance. The influence of variation of mean axial tension induced by elongation of flexible cylinder was evaluated, which was shown to be not negligible in numerical simulation of VIV of a long flexible cylinder.

关键词： Vortex-Induced Vibration (VIV) nonlinear wake oscillator flexible cylinder integral transform

THE EFFECT OF MEMORY TERMS IN DIFFUSION PHENOMENA

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Journal of Computational Mathematics 2006年第1期24卷 91-102页

作者： A. Araújo J.A. Ferreira P. Oliveira Departamento de Matemática Universidade de Coimbra Portugal

In this paper the effect of integral memory terms in the behavior of diffusion phenomena is studied. The energy functional associated with different models is analyzed and stability inequalities are established. Approximation methods for the computation of the solution of the integro-differential equations are constructed. Numerical results are included.

关键词： Heat propagation Integro-differential equation Numerical approximation,Splitting method

Application of formal languages in polynomial transformations of instances between NP-complete problems

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第8期14卷 623-633页

作者： Jorge A. RUIZ-VANOYE Joaquín PREZ-ORTEGA Rodolfo A. PAZOS RANGEL Ocotlán DíAZ-PARRA Héctor J. FRAIRE-HUACUJA Juan FRAUSTO-SOLíS Gerardo REYES-SALGADO Laura CRUZ-REYES DACI Universidad Autónoma del Carmen Computer Science Centro Nacional de Investigación y Desarrollo Tecnológico Systems and Computer Science Instituto Tecnológico de Ciudad Madero Informatics Universidad Politécnica del Estado de Morelos Computer Science Instituto Tecnológico de Cuautla

We propose the usage of formal languages for expressing instances of NP-complete problems for their application in polynomial transformations. The proposed approach, which consists of using formal language theory for polynomial transformations, is more robust, more practical, and faster to apply to real problems than the theory of polynomial transformations. In this paper we propose a methodology for transforming instances between NP-complete problems, which differs from Garey and Johnson's. Unlike most transformations which are used for proving that a problem is NP-complete based on the NP-completeness of another problem, the proposed approach is intended for extrapolating some known characteristics, phenomena, or behaviors from a problem A to another problem B. This extrapolation could be useful for predicting the performance of an algorithm for solving B based on its known performance for problem A, or for taking an algorithm that solves A and adapting it to solve B.

关键词： Formal languages Polynomial transformations NP-completeness

Fermion bound states in geometrically deformed backgrounds

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Chinese Physics C 2019年第1期43卷 1-8页

作者： D.Bazeia A.Mohammadi D.C.Moreira Departamento de Física Universidade Federal da Paraíba Departamento de Física Universidade Federal de Pernambuco Unidade Acadêmica de Física Universidade Federal de Campina Grande

This work deals with the behavior of fermions in the background of kinklike structures in the twodimensional spacetime. The kinklike structures appear from bosonic scalar field models that engender distinct profiles and interact with the fermion fields via the standard Yukawa coupling. We first consider two models that engender parity symmetry, one leading to the exclusion of fermion bound states, and the other to the inclusion of bound states, when the parameter that controls the bosonic structure varies from zero to unity. We then investigate a third model where the kinklike solution explicitly breaks parity symmetry, leading to fermion bound states that are spatially asymmetric.

关键词： topological defect fermion interaction bound state

Distinct physiological mechanisms underpin growth and rehydration of Hymenaea courbaril and Hymenaea stigonocarpa upon short-term exposure to drought stress

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Journal of Forestry Research 2023年第1期34卷 113-123页

作者： Luana M.Luz Ediane C.Alves Nariane Q.Vilhena Tamires B.Oliveira Zara G.B.Silva Joze M.N.Freitas Candido F.O.Neto Roberto C.L.Costa Lucas C.Costa universidade Federal Rural da AmazOia CapanemaPA 68700-665Brazil universidade Federal Rural da AmazEia BelémPA 66077-830Brazil

Plants hold biochemical and physiological mechanisms to withstand drought ***,depending on water deficit interval,plant rehydration relies on how it can retain growth or a positive water balance—or rarely *** this study,two species of Hymenaea,one from the Amazon and the other from the Brazilian Cerrado,were investigated for their physiological mechanism associated with growth rehydration upon short-term exposure to drought *** findings demonstrate that Hymenaea courbaril tends to invest in nitrogen to the detriment of carbon compounds,-as it is limited by lower net photosynthesis-and adjust root growth to attenuate drought stress *** contrast,Hymenaea stigonocarpa takes advantage of higher water potential and a basal rate of lower net photosynthesis to support aboveground growth under such ***,it is postulated that there are distinct ways of controlling water status and growth between *** and ***,which are determined either by the ability of the species to keep net photosynthesis at low levels of water content or by favoring the accumulation of nitrogen *** mechanisms were effective with regards to water use efficiency and thus it is reasonable to suggest that strategies are not exclusive and may work under adverse conditions,as observed in Amazon and Brazilian Cerrado ***.

关键词： Hymenaea courbaril Hymenaea stigonocarpa Growth Photosynthesis Water deficit

Environmental parameters and tree physiology in two semiarid land use systems in Brazil

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Journal of Forestry Research 2019年第2期30卷 397-407页

作者： Marlete Moreira Mendes Ivanov Claudivan Feitosa de Lacerda Francisco Eden Fernandes Paiva Ana Clara Rodrigues Cavalcante Teogenes Senna de Oliveira Departamento de Biologia Universidade Federal do Piaui Departamento de Engenharia Agricola Campus do PiciUniversidade Federal do Ceara Embrapa Caprinos e Ovinos Departamento de Solos Universidade Federal de Vicosa

To determine if reduced tree densities(number of trees per unit area) lead to changes in micro-meteorological and tree physiological characteristics, two areas with different tree densities were assessed. One was an agrosilvopastoral system(AGP) with low tree density, and the other, a secondary forest(SF) with greater tree numbers, both located in a semiarid region of Brazil. Data were collected simultaneously by two automated weather stations: rainfall, air(T_a) and soil temperatures(T_(s5 cm)), relative humidity(RHair), photosynthetically active radiation(PAR), soil moisture at two depths(M_(s30 cm)and M_(s50 cm)),and wind velocity(Vw). Net photosynthesis in Cordia oncocalyx Allema?o trees was measured with an infrared gas analyzer in February, March, May, July, August and September 2011, which encompasses a rainy period followed by a dry period. Average values of Ta, T_(s5 cm), Vwand PAR were greater and average values of RHairand M_(s50 cm) were lesser in the AGP. Photosynthetic rates were greater in plants growing under the AGP at the onset of the dry season when Vw, PAR and T_(s5 cm)were greater and M_(s50 cm) was lesser. Photosynthetic rates correlated strongly with physical parameters during the dry season, especially under SF. Differences in tree numbers between AGP and SF led to differences in physical environmental parameters;however, the latter had less influence on photosynthetic rates in C. oncocalyx during the rainy season. During the dry season, all physical parameters had an impact on net photosynthesis under SF but not under AGP. This indicates a certain independence of plants in AGP.

关键词： Agrosilvopastoral system Net photosynthesis Secondary forest Tree density

Structural and biological engineering of 3D hydrogels for wound healing

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Bioactive Materials 2023年第6期24卷 197-235页

作者： Mohammad Hadi Norahan Sara Cristina Pedroza-González Mónica Gabriela Sánchez-Salazar Mario Moisés Álvarez Grissel Trujillo de Santiago Escuela de Ingeniería y Ciencias Tecnológico de MonterreyMonterreyNL64849Mexico Centro de Biotecnología-FEMSA Tecnológico de MonterreyMonterreyNuevo LeónCP64849Mexico Departamento de Bioingeniería Tecnológico de MonterreyMonterreyNuevo LeónCP64849Mexico

Chronic wounds have become one of the most important issues for healthcare systems and are a leading cause of death *** dressings are necessary to facilitate wound *** wound dressings may substantially reduce healing time,reduce the risk of recurrent infections,and reduce the disability and costs *** the path of engineering of an ideal wound dressing,hydrogels have played a leading *** are 3D hydrophilic polymeric structures that can provide a protective barrier,mimic the native extracellular matrix(ECM),and provide a humid *** to their advantages,hydrogels(with different architectural,physical,mechanical,and biological properties)have been extensively explored as wound dressing *** we describe recent studies on hydrogels for wound healing applications with a strong focus on the interplay between the fabrication method used and the architectural,mechanical,and biological performance ***,we review different categories of additives which can enhance wound regeneration using 3D hydrogel *** engineering for wound healing applications promises the generation of smart solutions to solve this pressing problem,enabling key functionalities such as bacterial growth inhibition,enhanced re-epithelialization,vascularization,improved recovery of the tissue functionality,and overall,accelerated and effective wound healing.

关键词： Wound healing Wound dressing Hydrogel Tissue engineering 3D culture

MEAT AND MEAT PRODUCTS

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Journal of Integrative Agriculture 2013年第11期12卷 1916-1918页

作者： José M Lorenzo Centro tecnológico de la Carne de Galicia

In recent years, meat quality has assumed a greater consumer significance and public attention. There is growing awareness of the link between diet and health and this is reflected in the demand for more information a... 详细信息

关键词： MEAT AND MEAT PRODUCTS

Pathophysiology of cystic fibrosis and drugs used in associated digestive tract diseases

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World Journal of Gastroenterology 2013年第46期19卷 8552-8561页

作者： Adriana Haack Giselle Gonalves Arago Maria Rita Carvalho Garbi Novaes Department of Health Universidade Paulista (UNIP)

Cystic fibrosis(CF)causes chronic infections in the respiratory tract and alters the digestive *** paper reviews the most important aspects of drug treatment and changes in the digestive tract of patients with *** is a review of the literature,emphasizing the discoveries made within the last 15 years by analyzing scientific papers published in journals indexed in the Scientific Electronic Library Online,Sciences Information,United States National Library of Medicine and Medical Literature Analysis and Retrieval System Online databases,both in English and Portuguese,using the key words:cystic fibrosis,medication,therapeutic,absorption,***,observational,experimental,and epidemiological clinical studies were selected,among others,with statistical significance of 5%.This review evaluates the changes found in the digestive tract of CF patients including pancreatic insufficiency,constipation and liver *** in nutritional status are also *** treatment,nutritional supplementation and drug management were classified in this review as essential to the quality of life of CF patients,and became available through public policies for monitoring and treating *** information gathered on CF and a multi professional approach to the disease is essential in the treatment of these patients.

关键词： Cystic fibrosis Medication Therapeutic Absorption digestion

Neumann Boundary Conditions Inhibiting SSB in Coleman-Weinberg Mechanism

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Communications in Theoretical Physics 2010年第12期54卷 1071-1074页

作者： F.N.Fagundes R.O.Francisco B.B.Dilem J.A.Nogueira universidade Federal do Espírito Santo

In this work we show that homogeneous Neumann boundary conditions inhibit the Coleman-Weinberg mechanism for spontaneous symmetry breaking in the scalar electrodynamics if the length of the finite region is small enou... 详细信息

关键词： scalar electrodynamics Neumann boundary conditions spontaneous symmetry breaking