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Journal of Sport and Health Science 2021年第4期10卷 447-453页

作者： Kate Parker Anna Timperio Jo Salmon Karen Villanueva Helen Brown Irene Esteban-Cornejo Veronica Cabanas-Sánchez José Castro-Pinero David Sánchez-Oliva oscarl.veiga School of Exercise and Nutrition Sciences Institute for Physical Activity and Nutrition(IPAN)Deakin UniversityGeelongVIC 3220Australia Centre for Urban Research School of Global Urban and Social StudiesRMIT UniversityMelbourneVIC 3000Australia Center for Cognitive and Brain Health Department of PsychologyNortheastern UniversityBostonMA 02115USA PROmoting FITness and Health through physical activity(PROFITH)research group Department of Physical Education and SportsFaculty of Sport SciencesUniversity of GranadaGranada 18010Spain Department of Physical Education Sports and Human MovementAutonomous University of MadridMadrid 28049Spain Research Centre in Physical Activity Health and Leisure(CIAFEL)Faculty of SportUniversity of PortoPorto 4099-002Portugal Department of Physical Education Faculty of Education SciencesUniversity of CadizPuerto Real 11003Spain Biomedical Research and Innovation Institute of Cadiz(INiBICA) Cadiz 11003Spain

Background:Children and adolescents can be distinguished by different typologies(clusters) of physical activity and sedentary *** physical activity and sedentary behaviors change over time within different typologies is not *** study examined longitudinal changes in physical activity and sedentary time among children and adolescents with different baseline typologies of activity-related ***:In this longitudinal study(3 annual time points) of children(n=600,age=9.2±0.4 years(mean±SD),50.3% girls) and adolescents(n=1037,age=13.6±1.7 years,48.4% girls),participants were recruited in Spain in *** class analyses identified typologies based on self-reported screen,educational,social and relaxing sedentary behaviors,active travel,muscle strengthening activity,and sport at *** each typology,linear mixed growth models explored longitudinal changes in accelerometer-derived moderate-to-vigorous physical activity and sedentary time,as well as time by class ***:Three typologies were identified among children( "social screenies",12.8%;"exercisers",61.5%;and "non-sporty active commuters",25.7%) and among adolescents "active screenies",43.5%;"active academics",35.0%;and "non-sporty active commuters",21.5%) at *** time increased within each typology among children and adolescents,with no significant differences between *** changes in physical activity were found in any typology among *** adolescents,physical activity declined within all typologies,with "non-sporty active commuters" declining significantly more than "active screenies" over 3 ***:These results support the need for interveation to promote physical activity and prevent increases in sedentary time during childhood and *** characterized as "non-sporty active commuters" may require specific interventions to maintain their physical activity over time.

关键词： Behavior change Physical activity Sedentary behavior Typologies Youth

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Survival effects of antibiotic exposure during the larval and adult stages in the West Nile virus vector Culex pipiens

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Insect Science 2024年第2期31卷 542-550页

作者： Marta Garrigos Mario Garrido Manuel Morales-Yuste JosuéMartinez-de la Puente Jesus veiga Faculty of Pharmacy Department of ParasitologyUniversity of GranadaGranadaSpain CIBER de Epidemiologia y Salud Publica(CIBERESP) MadridSpain

The ability of mosquitoes to transmit a pathogen is affected,among other factors,by their survival rate,which is partly modulated by their *** microbiota is acquired during the larval phase and modified during their development and adult feeding behavior,being highly dependent on environmental *** residues including antibiotics are widespread pollutants potentially being present in mosquito breeding waters likely affecting their ***,we used Culex pipiens mosquitoes to assess the impact of antibiotic exposure during the larval and adult stages on the survival rate of adult ***-collected larvae were randomly assigned to two treatments:larvae maintained in water supplemented with antibiotics and control *** adults were subsequently assigned to each of two treatments,fed with sugar solution with antibiotics and fed only with sugar solution(controls).Larval exposure to antibiotics significantly increased the survival rate of adult females that received a control *** addition,the effect of adult exposure to antibiotics on the survival rate of both male and female mosquitoes depended on the number of days that larvae fed ad libitum in the laboratory before *** particular,shorter larval ad libitum feeding periods reduced the survival rate of antibiotic-treated adult mosquitoes compared with those that emerged after a longer larval feeding *** differences were not found in control adult *** results extend the current understanding of the impact of antibiotic exposure of mosquitoes on a key component of vectorial capacity,that is the vector survival rate.

关键词： antibiotics avian malaria microbiota mosquitoes vector competence vector survival

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On Mixed Pressure-Velocity Regularity Criteria to the Navier-Stokes Equations in Lorentz Spaces

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Chinese Annals of Mathematics,Series B 2021年第1期42卷 1-16页

作者： Hugo BEIRAO da veiga Jiaqi YANG Department of Mathematics Pisa UniversityPisa Italy School of Mathematicsand Statistics Northwestern Polytechnical UniversityXi'an 710129China

In this paper the authors derive regular criteria in Lorentz spaces for LerayHopf weak solutions v of the three-dimensional Navier-Stokes equations based on the formal equivalence relationπ≌|v|^(2),whereπdenotes the fluid pressure and v denotes the fluid *** is called the mixed pressure-velocity problem(the P-V problem for short).It is shown that if(π/(e-^|(x)|^(2)+|v|^(θ)∈L^(p)(0,T;L^(q,∞)),where 0≤θ≤1 and 2/p+3/q=2-θ,then v is regular on(0,T].Note that,ifΩ,is periodic,e^(-|x|)^(2) may be replaced by a positive *** result improves a 2018 statement obtained by one of the ***,as an integral part of the contribution,the authors give an overview on the known results on the P-V problem,and also on two main techniques used by many authors to establish sufficient conditions for regularity of the so-called Ladyzhenskaya-Prodi-Serrin(L-P-S for short)type.

关键词： Navier-Stokes equations Pressure≌square velocity Regularity criteria Lorentz spaces

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Navier-Stokes equations under slip boundary conditions:Lower bounds to the minimal amplitude of possible time-discontinuities of solutions with two components in L^(∞)(L^(3))

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Science China Mathematics 2022年第10期65卷 2099-2122页

作者： Hugo Beirao da veiga Jiaqi Yang Department of Mathematics Pisa UniversityPisa 56127Italy School of Mathematics and Statistics Northwestern Polytechnical UniversityXi'an 710129China

The main purpose of this paper is to extend the result obtained by Beirao da veiga(2000)from the whole-space case to slip boundary *** by a two components of the velocity *** fix ideas setū=(u_(1),u_(2),0)(the half-space)orū=?_(1)ê_(1)+?_(2)ê_(2)(the general boundary case(see(7.1))).We show that there exists a constant K,which enjoys very simple and significant expressions such that if at some timeτ∈(0,T)one has lim sup_(t→^(τ)-0)‖ū(t)‖_(L^(3)(Ω))^(3)<‖ū(τ)‖_(L^(3)(Ω))^(3)+K,then u is continuous atτwith values in L^(3)(Ω).Roughly speaking,the above norm-discontinuity of merely two components of the velocity cannot occur for steps'amplitudes smaller than *** particular,if the above condition holds at eachτ∈(0,T),the solution is smooth in(0,T)×Ω.Note that here there is no limitation on the width of the norms‖ū(t)‖_(L^(3)(Ω))^(3)·So K is independent of these *** other related results are discussed and compared among them.

关键词： Navier-Stokes equations singular case slip boundary conditions regularity two components

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On Mixed Pressure-Velocity Regularity Criteria to the Navier-stokes Equations in Lorentz Spaces,Part Ⅱ:The Non-slip Boundary Value Problem

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Chinese Annals of Mathematics,Series B 2022年第1期43卷 51-58页

作者： Hugo BEIRÃO DA veiga Jiaqi YANG Department of Mathematics Pisa UniversityPisaItaly School of Mathematics and Statistics Northwestern Polytechnical UniversityXi'an 710129China

This paper is a continuation of the authors recent work[Beirao da veiga,*** Yang,J.,On mixed pressure-velocity regularity criteria to the Navier-Stokes equations in Lorentz spaces,***.,42(1),2021,1-16],in which mixed pressure-velocity criteria in Lorentz spaces for Leray-Hopf weak solutions of the three-dimensional Navier-Stokes equations,in the whole space R^(3) and in the periodic torus T^(3),are *** purpose of the present work is to extend the result of mentioned above to smooth,bounded domains Ω,under the non-slip boundary *** π denote the fluid pressure and v the fluid *** is shown that if π/(1+|v|^(θ))∈L^(p)(0,T;L^(q,∞)(Ω)),where 0≤θ≤1,and 2/p+3/q=2-θwith p≥2,then v is regular on Ω×(0,T].

关键词： Navier-Stokes equations Pressure-speed links Regularity criteria Lorentz spaces Boundary value problem

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Neural Network-Based Limiter with Transfer Learning

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Communications on Applied Mathematics and Computation 2023年第2期5卷 532-572页

作者： Rémi Abgrall Maria Han veiga University of Zurich ZurichSwitzerland University of Michigan Ann ArborUSA

Recent works have shown that neural networks are promising parameter-free limiters for a variety of numerical schemes(Morgan et *** A machine learning approach for detect-ing shocks with high-order hydrodynamic *** *** J Comput Phys 367:166-191.,2018;veiga et *** European Conference on Computational Mechanics andⅦEuropean Conference on Computational Fluid Dynamics,vol.1,***.,2018).Following this trend,we train a neural network to serve as a shock-indicator function using simulation data from a Runge-Kutta discontinuous Galer-kin(RKDG)method and a modal high-order limiter(Krivodonova in J Comput Phys 226:879-896.,2007).With this methodology,we obtain one-and two-dimensional black-box shock-indicators which are then coupled to a standard ***,we describe a strategy to transfer the shock-indicator to a residual distribution(RD)scheme without the need for a full training cycle and large data-set,by finding a mapping between the solution feature spaces from an RD scheme to an RKDG scheme,both in one-and two-dimensional problems,and on Cartesian and unstruc-tured *** report on the quality of the numerical solutions when using the neural network shock-indicator coupled to a limiter,comparing its performance to traditional lim-iters,for both RKDG and RD schemes.

关键词： Limiters Neural networks Transfer learning Domain adaptation

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A comparison of the management models of protected areas between China and the southern Africa region

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Forestry Studies in China 2010年第3期12卷 151-157页

作者： Claudino DA veiga MENDONA College of Science of Nature Conservation Beijing Forestry University

A comparison of the management models of protected areas between China and the African south region allows reading and evaluating the similarities and differences in the use of management model as a management tool for protected areas and specifi- cally some positive and negative features of the management approaches in these two regions. Previous to this study it verified the designation of protected areas as increasing at a faster rate than ever before, comparatively much faster now in China than southern Africa regions. With the aim of evaluating similarities and differences in the use of management model as a management tool for pro- tected areas in China and southern Africa Region, both qualitative and quantitative data were collected. Qualitative data were mainly from policy documents, scientific articles and magazine reports, whereas quantitative （secondary data） statistical data from Interna- tional Union for Conservation of Nature Resources （IUCN） and World Database on Protected Areas （WDPA）. In view of the data sources above, the study found that in China all the protected areas are state owned whilst in southern Africa regions there are some protected areas that are privately owned; also that the models or typology of governance applied are successful for the fact that they both combine co-management or collaborative management, community-conserved areas and private protected areas that are subject to greater success and can help design planning and management than those who use exclusively government management. To this, the study concluded that the use of management model is influenced by the type of governance a country applies to its reserved areas.

关键词： protected areas sustainability China southern Africa region management model

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Context-dependent insect predation pressure on an avian ectoparasite

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Insect Science 2023年第6期30卷 1784-1797页

作者： Angela Salido Jesús veiga Joaquín Luis Reyes-López Francisco Valera Department of Botany Ecology and Plant PhysiologyUniversity of CórdobaCórdobaSpain Departamento de Ecología Funcional y Evolutiva Estación Experimental de ZonasÁridas(EEZA-CSIC)AlmeríaSpain Department of Parasitology University of GranadaGranadaSpain MEMEG Department of BiologyLund UniversityLundSweden

Context dependence arises when ecological relationships vary with the conditions under which they are observed. Context dependence of interactions involving parasites is poorly known, even if it is key to understanding host–parasite relationships and food web dynamics. This paper investigates to which extent predation pressure on an avian ectoparasite (Carnus hemapterus) is context-dependent. Based on a predator-exclusion experiment, predation pressure on C. hemapterus pupae in the host's nest for 3 years, and its variation between habitat types are quantified. Variation in precipitation and normalized difference vegetation index (NDVI) is also explored as a likely cause of context dependency. We hypothesize that predation pressure should fluctuate with such surrogates of food availability, so that inter-annual and intra-annual differences may emerge. The number of nests with significant reduction of pupae varied widely among years ranging from 24% to 75%. However, average pupae reduction in nests where a significant reduction occurred did not vary between years. No differences in predation rates between habitat types were detected. Precipitation and NDVI varied widely between years and NDVI was consistently lower around nests on cliffs than around nests on trees and farmhouses. Parallels were found between variation in predation pressure and precipitation/NDVI at a wide scale (highest predation the driest year, and much lower the 2 rainier ones), but not at the nest scale. This paper shows clear context-dependent insect predation pressure on an ectoparasite under natural conditions, and that such interaction changes in signs rather than magnitude between years. The causes for these variations require longer-term studies and/or well-designed, large-scale experiments.

关键词： ants arid areas Carnus hemapterus consumer-resource interaction ecosys-tem productivity predator-parasite rainfall

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Serendipity Virtual Elements for General Elliptic Equations in Three Dimensions

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Chinese Annals of Mathematics,Series B 2018年第2期39卷 315-334页

作者： Lourenco BEIRAO DA veiga Franco BREZZI Franco DASSI Luisa Donatelia MARINI Alessandro RUSSO Dedicated to Philippe G. Ciarlet on the occasion of his 80th birthda

The authors study the use of the virtual element method(VEM for short) of order k for general second order elliptic problems with variable coefficients in three space dimensions. Moreover, they investigate numerically... 详细信息

关键词： Virtual element methods Polyhedral decompositions Linear ellipticproblems Serendipity

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Capturing Near-Equilibrium Solutions: A Comparison between High-Order Discontinuous Galerkin Methods and Well-Balanced Schemes

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Communications in Computational Physics 2019年第6期26卷 1-34页

作者： Maria Han veiga David A.Velasco-Romero Remi Abgrall Romain Teyssier Institute of Computational Science University of ZurichSwitzerland Institute of Mathematics University of ZurichSwitzerland Universidad Autonoma del Estado de Morelos Mexico Instituto de Ciencias Fisicas Universidad Nacional Aut́onoma de ḾexicoMexico

Equilibrium or stationary solutions usually proceed through the exact balance between hyperbolic transport terms and source terms. Such equilibrium solutions are affected by truncation errors that prevent any classical numerical scheme from capturing the evolution of small amplitude waves of physical significance. In order to overcome this problem, we compare two commonly adopted strategies: going to very high order and reduce drastically the truncation errors on the equilibrium solution, or design a specific scheme that preserves by construction the equilibrium exactly, the so-called well-balanced approach. We present a modern numerical implementation of these two strategies and compare them in details, using hydrostatic but also dynamical equilibrium solutions of several simple test cases. Finally, we apply our methodology to the simulation of a protoplanetary disc in centrifugal equilibrium around its star and model its interaction with an embedded planet, illustrating in a realistic application the strength of both methods.

关键词： Numerical methods benchmark well-balanced methods discontinuous Galerkin methods

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