On the construction of suitable weak solutions to the 3D Navier-Stokes equations in a bounded domain by an artificial compressibility method

In this paper we will prove that suitable weak solutions of three dimensional Navier-Stokes equations in bounded domain can be constructed by a particular type of artificial compressibility approximation

An elementary proof of uniqueness of the particle trajectories for solutions of a class of shear-thinning non-Newtonian 2D fluids

We prove some regularity results for a class of two dimensional non-Newtonian fluids. By applying results from [Dashti and Robinson, Nonlinearity, 22 (2009), 735-746] we can then show uniqueness of particle trajectories

Global regularity criterion for the 3D Navier-Stokes equations involving one entry of the velocity gradient tensor

In this paper we provide a sufficient condition, in terms of only one of the nine entries of the gradient tensor, i.e., the Jacobian matrix of the velocity vector field, for the global regularity of strong solutions to the three-dimensional Navier-Stokes equations in the whole space, as well as for the case of periodic boundary conditions

Pressure moderation and effective pressure in Navier-Stokes flows

We study the Cauchy problem of the Navier–Stokes equations by both semi-analytic and classical energy methods. The former approach provides a physical picture of how viscous effects may or may not be able to suppress singularity development. In the latter approach, we examine the pressure term that drives the dynamics of the velocity norms ||u||Lq , for q ≥ 3. A key idea behind this investigation is due to the fact that the pressure p in this term is determined upto a function of both space and |u|, say Ƥ(x, |u|), which may assume relatively broad forms. This allows us to use Ƥ as a pressure moderator in the evolution equation for ||u||Lq , whereby optimal regularity criteria can be sought by varying Ƥ within its admissible classes. New regularity criteria are derived with and without making use of the moderator. The results obtained in the absence of the moderator feature some improvement over existing criteria in the literature. Several criteria are derived in terms of the moderated (effective) pressure p+Ƥ. A simple moderation scheme and the plausibility of the present approach to the problem of Navier–Stokes regularity are discussed.PostprintPeer reviewe

Estilosantes Campo Grande como alternativa para recuperação e enriquecimento de pastagens nativas degradadas do Pantanal.

Este estudo objetivou avaliar a consorciação da gramínea nativa Mesosetum chaseae com estilosantes Campo Grande (ECG) para recuperação de pastagens degradadas no Pantanal. O experimento foi conduzido na sub-região da Nhecolândia, Pantanal, MS, em área de campo com sinais evidentes de degradação. O delineamento foi inteiramente casualizado com três repetições. O plantio de M. chaseae foi feito por mudas e ECG por sementes, no início das chuvas, em novembro de 2014. No final do período chuvoso foram feitas avaliações do valor nutritivo das pastagens e constatado o enriquecimento com a Introdução do ECG. Os teores médios de proteína bruta (%) e NDT (%) para M. chaseae e ECG foram de 10,9 e 57,2 e 5,3 e 52,3, respectivamente. A cobertura vegetal evoluiu de 75% para quase 100% no segundo ano, destacando algumas espécies forrageiras do banco natural de sementes e problemas no estabelecimento de ECG, provavelmente devido a inundação na área, reconhecendo a importância do manejo adaptativo.Edição dos anais do VI Congresso Latino-Americano de Agroecologia (CLAA), X Congresso Brasileiro de Agroecologia (CBA), V Seminário de Agroecologia do Distrito Federal e Entorno (SEMDF), set. 2017, Brasília, DF