Lowest order Virtual Element approximation of magnetostatic problems

We give here a simplified presentation of the lowest order Serendipity Virtual Element method, and show its use for the numerical solution of linear magneto-static problems in three dimensions. The method can be applied to very general decompositions of the computational domain (as is natural for Virtual Element Methods) and uses as unknowns the (constant) tangential component of the magnetic field $\mathbf{H}$ on each edge, and the vertex values of the Lagrange multiplier $p$ (used to enforce the solenoidality of the magnetic induction $\mathbf{B}=\mu\mathbf{H}$). In this respect the method can be seen as the natural generalization of the lowest order Edge Finite Element Method (the so-called "first kind N\'ed\'elec" elements) to polyhedra of almost arbitrary shape, and as we show on some numerical examples it exhibits very good accuracy (for being a lowest order element) and excellent robustness with respect to distortions

Exploring the role of fallopian ciliated cells in the pathogenesis of high-grade serous ovarian cancer

High-grade serous epithelial ovarian cancer (HGSOC) is the fifth leading cause of cancer death in women and the first among gynecological malignancies. Despite an initial response to standard chemotherapy, most HGSOC patients relapse. To improve treatment options, we must continue investigating tumor biology. Tumor characteristics (e.g., risk factors and epidemiology) are valuable clues to accomplish this task. The two most frequent risk factors for HGSOC are the lifetime number of ovulations, which is associated with increased oxidative stress in the pelvic area caused by ovulation fluid, and a positive family history due to genetic factors. In the attempt to identify novel genetic factors (i.e., genes) associated with HGSOC, we observed that several genes in linkage with HGSOC are expressed in the ciliated cells of the fallopian tube. This finding made us hypothesize that ciliated cells, despite not being the cell of origin for HGSOC, may take part in HGSOC tumor initiation. Specifically, malfunction of the ciliary beat impairs the laminar fluid flow above the fallopian tube epithelia, thus likely reducing the clearance of oxidative stress caused by follicular fluid. Herein, we review the up-to-date findings dealing with HGSOC predisposition with the hypothesis that fallopian ciliated cells take part in HGSOC onset. Finally, we review the up-to-date literature concerning genes that are located in genomic loci associated with epithelial ovarian cancer (EOC) predisposition that are expressed by the fallopian ciliated cells

Coeficiente de metabolizabilidade aparente de diferentes fontes lipídicas com ou sem emulsificante para frangos de corte de 1 a 8 dias.

Óleos e gorduras são utilizados nas rações de aves devido às suas altas concentrações calóricas. Entretanto, a escolha da fonte lipídica a ser utilizada na formulação dependerá de seu custo e da qualidade. O uso de emulsificantes em aves jovens tem o objetivo de auxiliar na digestão e absorção da gordura da dieta devido à imaturidade da circulação entero-hepática nesses animais (5). O objetivo do estudo foi avaliar o coeficiente de metabolizabilidade aparente da matéria seca (CMAMS) e extrato etéreo (CMAEE) e energia metabolizável (EM) em frangos de corte de 1 a 8 dias de idade alimentados com diferentes fontes lipídicas com ou sem a adição de emulsificantes

Digestibilidade de dietas com diferentes formas físicas para frangos de corte.

A peletização é o processamento térmico mais utilizado na indústria avícola, pois favorece o aproveitamento dos ingredientes e modifica a forma física da dieta. A pressão, umidade e temperatura empregadas por determinado tempo no processo, promovem alterações nas estruturas dos carboidratos, bem como das proteínas. O objetivo desse estudo foi avaliar o efeito de diferentes formas físicas (farelada ou peletizada/triturada com diferentes tempos de condicionamento) sobre o coeficiente de digestibilidade ileal aparente da matéria seca (CDIAMS), proteína bruta (CDIAPB) e energia digestível ileal (EDI) em frangos de corte de 1 a 25 dias

Robust Finite Elements for linearized Magnetohydrodynamics

We introduce a pressure robust Finite Element Method for the linearized Magnetohydrodynamics equations in three space dimensions, which is provably quasi-robust also in the presence of high fluid and magnetic Reynolds numbers. The proposed scheme uses a non-conforming BDM approach with suitable DG terms for the fluid part, combined with an $H^1$-conforming choice for the magnetic fluxes. The method introduces also a specific CIP-type stabilization associated to the coupling terms. Finally, the theoretical result are further validated by numerical experiments

Pressure robust SUPG-stabilized finite elements for the unsteady Navier-Stokes equation

In the present contribution we propose a novel conforming Finite Element scheme for the time-dependent Navier-Stokes equation, which is proven to be both convection quasi-robust and pressure robust. The method is built combining a "divergence-free" velocity/pressure couple (such as the Scott-Vogelius element), a Discontinuous Galerkin in time approximation, and a suitable SUPG-curl stabilization. A set of numerical tests, in accordance with the theoretical results, is included

Gyroid Lattice Heat Exchangers: Comparative Analysis on Thermo-Fluid Dynamic Performances

In recent years, additive manufacturing has reached the required reliability to effectively compete with standard production techniques of mechanical components. In particular, the geometrical freedom enabled by innovative manufacturing techniques has revolutionized the design trends for compact heat exchangers. Bioinspired structures, such as the gyroid lattice, have relevant mechanical and heat exchange properties for their light weight and increased heat exchange area, which also promotes the turbulent regime of the coolant. This work focuses its attention on the effect of the relevant design parameters of the gyroid lattice on heat exchange performances. A numerical comparative analysis is carried out from the thermal and fluid dynamic points of view to give design guidelines. The results of numerical analyses, performed on cylindrical samples, are compared to the experimental results on the pressure drop. Lattices samples were successfully printed with material extrusion, which is a low-cost and easy-to-use metal AM technology. For each lattice sample, counter pressure, heat exchange, and turbulence intensity ratio are calculated from the numerical point of view and discussed. At the end, the gyroid lattice is proven to be very effective at enhancing the heat exchange in cylindrical pipes. Guidelines are given about the choice of the best lattice, depending on the considered applications