BACKGROUND/PURPOSE Dental rotary instruments can be applied in multiple conditions of canals, but unpredictable fatigue fracture may happen. This study evaluated the fatigue lives of two batches of nickel-titanium (NiTi) dental rotary files operating in clinically simulated root canals. METHODS Single-step cyclic fatigue tests were carried out to assess the performance of two batches of NiTi ...

In 1972, I.I. Kotov proposed to separate the surfaces of congruent sections into a class and include plane-and-parallel translation, revolution, carved Monge, cyclic with generatrix circle constant radius, rotative, spiroidal, helical in it. The aim research is obtain generalized parametric equations pendulum type on right cylinders translation movable rigid superellipses. Analytical geometry m...

Gold and glassy carbon electrode surfaces were modified with L-cysteine, the electrochemical behavior of ascorbic acid (AA) was investigated on these new surfaces. To improve efficiency electrodes, optimum conditions for AA determination established. Electrochemical experiments performed at different potential ranges, concentration AA, scan rates, number polymerization cycles pH values. Using c...

Modification of metal surfaces with antimicrobial peptides is a promising approach to reduce bacterial adhesion. Here, cyclic peptides or cycloids, possessing remarkable stability and antimicrobial activities, were extracted and purified from Viola philippica Cav., and identified using mass spectrometry. Cyclotides were subsequently utilized to modify stainless steel surfaces via polydopamine-m...

1. Laboratório de Helmintoses Intestinais do Centro de Pesquisas René Rachou da Fundação Oswaldo Cruz, Belo Horizonte, MG, Brasil. 2. Departamento de Patologia do Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, RJ, Brasil. Apoio financeiro: PAPES 2/FIOCRUZ. Endereço para correspondência: Dr. Omar S. Carvalho. Centro de Pesquisas René Rachou/FIOCRUZ. Av. Augusto de Lima 1715, Barro Preto, 30190-...

We report on the fabrication and measurement of devices designed to study the electrochemical behavior of individual monolayer graphene sheets as electrodes. We have examined both mechanically exfoliated and chemical vapor deposited (CVD) graphene. The effective device areas, determined from cyclic voltammetric measurements, show good agreement with the geometric area of the graphene sheets, in...

The data reported in literature demonstrate that carbon paste electrodes (CPEs) are very suitable for a variety of applications and many works have thus been devoted in the development of new sensitive and selective electrode surfaces based on carbon paste as the electrode material of choice. The application of novel and promising carbonaceous materials, as electrode surfaces, is an issue of gr...

Targeting protein surfaces and protein-protein interactions (PPIs) with small molecules is a frontier goal of chemical biology and provides attractive therapeutic opportunities in drug discovery. The molecular properties of protein surfaces, including their shallow features and lack of deep binding pockets, pose significant challenges, and as a result have proved difficult to target. Peptides a...

We successfully prepared Au-nanoparticle-decorated ZnS (ZnS-Au) spheres by sputtering Au ultrathin films on surfaces of hydrothermally synthesized ZnS spheres and subsequently postannealed the samples in a high-vacuum atmosphere. The Au nanoparticles were distributed on ZnS surfaces without substantial aggregation. The Au nanoparticle diameter range was 5 to 10 nm. Structural information showed...

We discuss the spectral curves and rational maps associated with SU(2) Bogomolny monopoles of arbitrary charge k. We describe the effect on the rational maps of inverting monopoles in the plane with respect to which the rational maps are defined, and discuss the monopoles invariant under such inversion. We define the strongly centred monopoles, and show they form a geodesic submanifold of the k...