On the set of supercyclic operators

In this article, we address a problem posed by F. Bayart regarding the existence of an infinite-dimensional closed vector subspace (excluding the null operator) within the set of supercyclic operators on Banach spaces. We resolve this problem by establishing the existence of the closed subspace. Furthermore, we prove that the set of supercyclic operators on $\ell_1$ contains, up to the null operator, an isometric copy of $\ell_1$.Comment: 11 page

Characterization of a Copper Powder for Heat Pipe Wick Applications

In powder metallurgy, it is necessary to know the powder's nature to understand how the processing of a powder occurs. In this paper, a characterization of a copper powder for heat pipe wick applications was experimentally done. The copper powder manufacturing method was atomization. This metallic powder was characterized by Scanning Electron Microscopy (SEM), X-Ray Fluorescence Spectrometry (ED-XRF), and Laser Diffraction Granulometry. As a result, the purity and the shape are compatible with the powder manufacturing method and great for wicks. Also, the copper powder has a unimodal distribution that is excellent for capillary structures

Upregulation of Nrf2 and decreased redox signaling contribute to renoprotective effects of chemerin receptor blockade in diabetic mice

Chemerin, acting through its receptor ChemR23, is an adipokine associated with inflammatory response, glucose and lipid metabolism and vascular function. Although this adipokine has been associated with the development and progression of kidney disease, it is not clear whether the chemerin/ChemR23 system plays a role in renal function in the context of diabetes. Therefore, we sought to determine whether ChemR23 receptor blockade prevents the development and/or progression of diabetic nephropathy and questioned the role of oxidative stress and Nrf2 in this process. Renal redox state and function were assessed in non-diabetic lean db/m and diabetic obese db/db mice treated with vehicle or CCX832 (ChemR23 antagonist). Renal reactive oxygen species (ROS) production, which was increased in diabetic mice, was attenuated by CCX832. This was associated with an increase in Nox 4 expression. Augmented protein oxidation in db/db mice was not observed when mice were treated with CCX832. CCX832 also abrogated impaired Nrf2 nuclear activity and associated downregulation in antioxidants expression in kidneys from db/db mice. Our in vivo findings highlight the role of the redox signaling and Nrf2 system as renoprotective players during chemerin receptor blockade in diabetic mice. The chemerin/ChemR23 system may be an important target to limit renal dysfunction associated with obesity-related diabetes

Calculation of the influence of slot geometry on the magnetic flux density of the air gap

The objective of this work is to investigate the influence of slotted air gap constructive parameters on magnetic flux density of rotating machines. For this purpose, different approaches were used to solve the air gap field diagram using finite element method and the magnetic field distribution uniformity was evaluated by Carter's factor calculation on two-dimensional and three-dimensional models. Sensitivity analysis of slot constructive parameters was performed and results show that slot geometry modifies the magnetic flux on air gap and shifts the air gap magnetic equipotential midline of double slotted machines. Finally, minimization of Carter’s factor on two-dimensional model presents an optimized slot geometry with a near uniform magnetic flux density distribution

THE SUSCEPTIBILITY OF RECENT ISOLATES OF Schistosoma mansoni TO PRAZIQUANTEL

Introduction: Schistosomiasis is a chronic disease caused by trematode flatworms of the genus Schistosoma and its control is dependent on a single drug, praziquantel (PZQ), but concerns over PZQ resistance have renewed interest in evaluating the in vitro susceptibility of recent isolates of Schistosoma mansoni to PZQ in comparison with well-established strains in the laboratory. Material and methods: The in vitro activity of PZQ (6.5-0.003 µg/mL) was evaluated in terms of mortality, reduced motor activity and ultrastructural alterations against S. mansoni. Results: After 3 h of incubation, PZQ, at 6.5 µg/mL, caused 100% mortality of all adult worms in the three types of recent isolates, while PZQ was inactive at concentrations of 0.08-0.003 µg/mL after 3 h of incubation. The results show that the SLM and Sotave isolates basically presented the same pattern of susceptibility, differing only in the concentration of 6.5 µg/mL, where deaths occurred from the range of 1.5 h in Sotave and just in the 3 h range of SLM. Additionally, this article presents ultrastructural evidence of rapid severe PZQ-induced surface membrane damage in S. mansoni after treatment with the drug, such as disintegration, sloughing, and erosion of the surface. Conclusion: According to these results, PZQ is very effective to induce tegument destruction of recent isolates of S. mansoni