Search results for "interference"

Surface plasmon interference fringes in back-reflection

2010

We report the experimental observation of surface plasmon polariton (SPP) interference fringes with near-unity visibility and half-wavelength periodicity obtained in back reflection on a Bragg mirror. The presented method based on leakage radiation microscopy (LRM) represents an alternative solution to optical near-field analysis and opens new ways for the quantitative analysis of SPP fringes. With LRM we investigate various SPP interference patterns and analyze the high reflectivity of Bragg mirror in comparison with theoretical models.

Diffractive optics for processing ultrashort light pulses

2011

In this work we combine, in principle, two disjoint optical fields, diffractive optics and ultrashort light radiation. This combination allows us to manipulate in a very unconventional manner femtosecond pulses and, on the other hand, to implement a set of novel applications. In our case we have focused our attention on material processing and biophotonics applications.

Endothelial transcriptomic changes induced by oxidized low density lipoprotein disclose an up-regulation of Jak-Stat pathway.

2015

Oxidized low density lipoproteins (oxLDLs) act as an etiological factor in the development of atherosclerosis by modifying the biological properties of endothelial cells through mechanisms of vascular inflammation. To deepen the oxLDL changes at cellular level, a transcriptomic analysis of human umbilical artery endothelial cells (HUAECs) treated with oxLDL was performed to identify the modified signaling pathways. Total RNA was isolated from HUAECs treated with oxLDL (100 μg/ml). Gene expression analysis was carried out using Affymetrix oligonucleotide microarrays. Biological pathway analysis was performed using Ingenuity Pathway Analysis software. Microarray assay demonstrated that oxLDL …

<title>Amorphous chalcogenide semiconductor resists for holography and electron-beam lithography</title>

2001

The photo- and electron beam induced changes in solubility of amorphous chalcogenide semiconductor As-S-Se and As2S3 thin films have been studied. The possibilities of practical application of these materials as resists for the production of relief holograms and holographic optical elements are discussed. It is shown that the self-enhancement phenomenon of holographic recording in amorphous chalcogenide semiconductor films by light or thermal treatment can be used to increase the diffraction efficiency of the holograms.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Function and Evolution of Nematode RNAi Pathways

2019

Selfish genetic elements, like transposable elements or viruses, are a threat to genomic stability. A variety of processes, including small RNA-based RNA interference (RNAi)-like pathways, has evolved to counteract these elements. Amongst these, endogenous small interfering RNA and Piwi-interacting RNA (piRNA) pathways were implicated in silencing selfish genetic elements in a variety of organisms. Nematodes have several incredibly specialized, rapidly evolving endogenous RNAi-like pathways serving such purposes. Here, we review recent research regarding the RNAi-like pathways of Caenorhabditis elegans as well as those of other nematodes, to provide an evolutionary perspective. We argue tha…

Entanglement-induced electron coherence in a mesoscopic ring with two magnetic impurities

2006

We investigate the Aharonov-Bohm (AB) interference pattern in the electron transmission through a mesoscopic ring in which two identical non-interacting magnetic impurities are embedded. Adopting a quantum waveguide theory, we derive the exact transmission probability amplitudes and study the influence of maximally entangled states of the impurity spins on the electron transmittivity interference pattern. For suitable electron wave vectors, we show that the amplitude of AB oscillations in the absence of impurities is in fact not reduced within a wide range of the electron-impurity coupling constant when the maximally entangled singlet state is prepared. Such state is thus able to inhibit th…

Influence of stimulus color on the control of reaching-grasping movements.

2001

This kinematic study aimed to determine whether color is a stimulus property involved in the control of reaching-grasping movements. Subjects reached and grasped a target-object, located either on the right or on the left of the subject's midline. A distractor, placed along the subject's midline, could be randomly presented. The colors, i.e., both chromaticity (red and green stimuli were presented) and lightness, of the target and distractor were varied in experiment 1. Only stimulus lightness and only stimulus chromaticity were varied in experiments 2 and 3, respectively. In experiment 4 subjects matched with their thumb and index finger the size of the target-stimuli presented in experime…

Key carabid species drive spring weed seed predation of Viola arvensis

2020

SiRNA-mediated in vivo gene knockdown by acid-degradable cationic nanohydrogel particles

2017

Cationic nanohydrogel particles have become an attractive tool for systemic siRNA delivery, but improvement of their in vivo tolerance is desirable, especially to prevent potential long term side effects by tissue and cellular accumulation. Here, we designed novel ketal cross-linked cationic nanohydrogel particles that were assessed for reduced tissue accumulation and robust siRNA delivery in vitro and in vivo. An oligo-amine cross-linker equipped with a ketal moiety in its core was synthesized and applied to nanohydrogel cross-linking of self-assembled reactive ester block copolymers in DMSO. The resulting acid-sensitive cationic nanoparticles spontaneously disassembled over time in acidic…

Parabolic Pulse Amplifiers

2008

International audience; Recent studies in nonlinear optics have led to the discovery of a new class of ultrashort pulse generated in fiber amplifiers by the self-similar propagation of an arbitrary input pulse. These pulses with a parabolic shape and linear chirp, called `optical similaritons,' represent asymptotic solutions of the nonlinear Schrödinger equation with gain, towards which any initial pulse of given energy converges, independently of its intensity profile. Parabolic pulse amplifiers can be easily developed with standard optical fibers and commercial devices. Our goal here is to emphasize the main properties of similaritons and to discuss a few of their numerous new application…