Search results for "Statics"

Comparative theoretical study of the Ag–MgO (100) and (110) interfaces

1999

We have calculated the atomic and electronic structures of Ag–MgO(100) and (110) interfaces using a periodic (slab) model and an ab initio Hartree–Fock approach with a posteriori electron correlation corrections. The electronic structure information includes interatomic bond populations, effective charges, and multipole moments of ions. This information is analyzed in conjunction with the interface binding energy and the equilibrium distances for both interfaces for various coverages. There are significant differences between partly covered surfaces and surfaces with several layers of metal, and these can be understood in terms of electrostatics and the electron density changes. For complet…

Calculation of the electrostatic field in a dielectric-loaded waveguide due to an arbitrary charge distribution on the dielectric layer

2016

The goal of this paper is to study the electrostatic field due to an arbitrary charge distribution on a dielectric layer in a dielectric-loaded rectangular waveguide. In order to obtain this electrostatic field, the potential due to a point charge on the dielectric layer is solved in advance. The high computational complexity of this problem requires the use of different numerical integration techniques (e.g., Filon, Gauss-Kronrod, Lobatto, …) and interpolation methods. Using the principle of superposition, the potential due to an arbitrary charge distribution on a dielectric layer is obtained by adding the individual contribution of each point charge. Finally, a numerical differentiation o…

A polar/π model of interactions explains face-to-face stacked quinoid rings: a case study of the crystal of potassium hydrogen chloranilate dihydrate

2015

International audience; The nature of interactions between face-to-face staggered stacked quinoid rings with pi-systems, observed with a short inter-ring centroid. centroid distance, is analyzed by experimental and theoretical methods. Charge density studies based on X-ray diffraction and DFT calculations, complemented by impedance spectroscopy, were employed to define the electronic and structural characteristics of the quinoid rings responsible for their interactions within the crystal packing. The crystal packing is mainly stabilized by strong electrostatic interactions between the K+ cation and the hydrogen chloranilate anion. The proximity and orientation of the stacked quinoid rings i…

Macrocyclic complexes based on [N⋯I⋯N]+ halogen bonds

2021

New 1–2 nm macrocyclic iodine(I) complexes prepared VIA a simple ligand exchange reaction manifest rigid 0.5–1 nm cavities that bind the hexafluorophosphate anion in the gas phase. The size of the cavities and the electrostatic interactions with the iodine(I) cations influence the anion binding properties of these macrocyclic complexes.

Liquid Crystal Phases in Suspensions of Charged Plate-Like Particles

2012

International audience; Anisotropic interactions in colloidal suspensions have recently emerged as a route for the design of new soft materials. Nonisotropic particles can form nematic, smectic, hexatic, and columnar liquid crystals. Although the formation of these phases is well rationalized when excluded volume is solely at play, the role of electrostatic interactions still remains unclear and even less so when particles present a charge heterogeneity, for example, clays. Here, we use Monte Carlo simulations of concentrated suspensions of charged disk-like particles to reveal the role of Coulomb interactions and charge anisotropy underlying liquid crystal formation and structures. We obse…

Impact of accumulated dust particles' charge on the photovoltaic module performance

2016

Abstract This work is focused on analysing effect of accumulated dust particles' charge on PV module performance. In the Dundee University's laboratory, dust particles have been created through epoxy powder and charged by using corona and tribo-electric charging methods by varying the charge levels of the accumulated dust particles. The PV module output has analysed for finding a relation between charge levels of the accumulated dust particles and its output voltage. Obtained experimental results have shown that charge level of accumulated dust particles on PV module's have significant impact on its output and dust particle accumulations are not associated with panel tilt angle.

Recombinant factor VIII: past, present and future of treatment of hemophilia A.

2018

The development of recombinant factor VIII (rFVIII) was initially driven by the necessity to treat hemophilia A (HA) patients with FVIII concentrates without the risk of transmitting infectious agents. Over the last three decades the safety of rFVIII has been further improved by completely removing animal or human proteins from the manufacturing process, so that patients would not be exposed to known or emerging pathogens. Recent efforts have concentrated on improving the expression of rFVIII, reducing its immunogenicity and enhancing its pharmacokinetic (PK) behavior. These new goals have been possible thanks to the develop-ment of biotechnology and a better knowledge of the function and s…

Large-scale identification of functional microRNA targeting reveals cooperative regulation of the hemostatic system.

2018

Essentials MicroRNAs (miRNAs) regulate the molecular networks controlling biological functions such as hemostasis. We utilized novel methods to analyze miRNA-mediated regulation of the hemostatic system. 52 specific miRNA interactions with 11 key hemostatic associated genes were identified. Functionality and drugability of miRNA-19b-3p against antithrombin were demonstrated in vivo. SUMMARY: Background microRNAs (miRNAs) confer robustness to complex molecular networks regulating biological functions. However, despite the involvement of miRNAs in almost all biological processes, and the importance of the hemostatic system for a multitude of actions in and beyond blood coagulation, the role o…

2019

By using all atom molecular dynamics simulations, we studied the behavior of human DNA telomere sequences in guanine quadruplex (G4) conformation and in the presence of oxidative lesions, namely abasic sites. In particular, we evidenced that while removing one guanine base induces a significant alteration and destabilization of the involved leaflet, human telomere oligomers tend, in most cases, to maintain at least a partial quadruplex structure, eventually by replacing the empty site with undamaged guanines of different leaflets. This study shows that (i) the disruption of the quadruplex leaflets induces the release of at least one of the potassium cations embedded in the quadruplex channe…

Cell stimulation versus cell death induced by sequential treatments with pulsed electric fields and cold atmospheric pressure plasma

2018

Pulsed electric fields (PEFs) and cold atmospheric pressure plasma (CAP) are currently both investigated for medical applications. The exposure of cells to PEFs can induce the formation of pores in cell membranes and consequently facilitate the uptake of molecules. In contrast, CAP mainly acts through reactive species that are generated in the liquid environment. The objective of this study was to determine, if PEFs combined with plasma-treated cell culture medium can mutually reinforce effects on viability of mammalian cells. Experiments were conducted with rat liver epithelial WB-F344 cells and their tumorigenic counterpart WB-ras for a direct comparison of non-tumorigenic and tumorigenic…